Search results for: CFRP/steel double strap joints

Authors: M. V. Rane, Tareke Tekia

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Liquid desiccant based fresh air dehumidifiers can be gainfully deployed for air-conditioning, agro-produce drying and in many industrial processes. Regeneration of liquid desiccant can be done using direct firing, high temperature waste heat or solar energy. Solar energy is clean and available in abundance; however, it is costly to collect. A two stage liquid desiccant fresh air dehumidification system can offer Coefficient of Performance (COP), in the range of 1.6 to 2 for comfort air conditioning applications. High COP helps reduce the size and cost of collectors required. Performance tests on high temperature regenerator of a two stage liquid desiccant fresh air dehumidifier coupled with seasonally tracked flat plate like solar collector will be presented in this paper. The two stage fresh air dehumidifier has four major components: High Temperature Regenerator (HTR), Low Temperature Regenerator (LTR), High and Low Temperature Solution Heat Exchangers and Fresh Air Dehumidifier (FAD). This open system can operate at near atmospheric pressure in all the components. These systems can be simple, maintenance-free and scalable. Environmentally benign, non-corrosive, moderately priced Potassium Formate, KCOOH, is used as a liquid desiccant. Typical KCOOH concentration in the system is expected to vary between 65 and 75%. Dilute liquid desiccant at 65% concentration exiting the fresh air dehumidifier will be pumped and preheated in solution heat exchangers before entering the high temperature solar regenerator. In the solar collector, solution will be regenerated to intermediate concentration of 70%. Steam and saturated solution exiting the solar collector array will be separated. Steam at near atmospheric pressure will then be used to regenerate the intermediate concentration solution up to a concentration of 75% in a low temperature regenerator where moisture vaporized be released in to atmosphere. Condensed steam can be used as potable water after adding a pinch of salt and some nutrient. Warm concentrated liquid desiccant will be routed to solution heat exchanger to recycle its heat to preheat the weak liquid desiccant solution. Evacuated glass tube based seasonally tracked solar collector is used for regeneration of liquid desiccant at high temperature. Temperature of regeneration for KCOOH is 133°C at 70% concentration. The medium temperature collector was designed for temperature range of 100 to 150°C. Double wall polycarbonate top cover helps reduce top losses. Absorber integrated heat storage helps stabilize the temperature of liquid desiccant exiting the collectors during intermittent cloudy conditions, and extends the operation of the system by couple of hours beyond the sunshine hours. This solar collector is light in weight, 12 kg/m2 without absorber integrated heat storage material, and 27 kg/m2 with heat storage material. Cost of the collector is estimated to be 10,000 INR/m2. Theoretical modeling of the collector has shown that the optical efficiency is 62%. Performance test of regeneration of KCOOH will be reported.

Keywords: solar, liquid desiccant, dehumidification, air conditioning, regeneration

Procedia PDF Downloads 326

Authors: Simon Grossemy, Peggy P. Y. Chan, Pauline M. Doran

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Nerve tissue engineering is the main field of research aimed at finding an alternative to autografts as a treatment for nerve injuries. Scaffolds are used as a support to enhance nerve regeneration. In order to successfully design novel scaffolds and in vitro cell culture systems, a deep understanding of the factors affecting nerve regeneration processes is needed. Physical and biological parameters associated with the culture environment have been identified as potentially influential in nerve cell differentiation, including electrical stimulation, exposure to extracellular-matrix (ECM) proteins, dynamic medium conditions and co-culture with glial cells. The mechanisms involved in driving the cell to differentiation in the presence of these factors are poorly understood; the complexity of each of them raises the possibility that they may strongly influence each other. Some questions that arise in investigating nerve regeneration include: What are the best protein coatings to promote neural cell attachment? Is the scaffold design suitable for providing all the required factors combined? What is the influence of dynamic stimulation on cell viability and differentiation? In order to study these effects, scaffolds adaptable to bioreactor culture conditions were designed to allow electrical stimulation of cells exposed to ECM proteins, all within a dynamic medium environment. Gold coatings were used to make the surface of viscose rayon microfiber scaffolds (VRMS) conductive, and poly-L-lysine (PLL) and laminin (LN) surface coatings were used to mimic the ECM environment and allow the attachment of rat PC12 neural cells. The robustness of the coatings was analyzed by surface resistivity measurements, scanning electron microscope (SEM) observation and immunocytochemistry. Cell attachment to protein coatings of PLL, LN and PLL+LN was studied using DNA quantification with Hoechst. The double coating of PLL+LN was selected based on high levels of PC12 cell attachment and the reported advantages of laminin for neural differentiation. The underlying gold coatings were shown to be biocompatible using cell proliferation and live/dead staining assays. Coatings exhibiting stable properties over time under dynamic fluid conditions were developed; indeed, cell attachment and the conductive power of the scaffolds were maintained over 2 weeks of bioreactor operation. These scaffolds are promising research tools for understanding complex neural cell behavior. They have been used to investigate major factors in the physical culture environment that affect nerve cell viability and differentiation, including electrical stimulation, bioreactor hydrodynamic conditions, and combinations of these parameters. The cell and tissue differentiation response was evaluated using DNA quantification, immunocytochemistry, RT-qPCR and functional analyses.

Keywords: bioreactor, electrical stimulation, nerve differentiation, PC12 cells, scaffold

Procedia PDF Downloads 215

Authors: Mohammad Hossein Pazandeh, Monir Doudi, Sona Rostampour Yasouri

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—Results The prudent administration of antibiotics aims to avoid the side effects and the microbes' resistance to antibiotics. An approach developing methods of local administration of antibiotics is especially required for localized infections caused by bacterial colonization of medical devices or implant materials. Among the wide variety of materials used as drug delivery systems, bioactive glasses (BG) have large utilization in regenerative medicine . firstly, the production of bioactive glass/nickel oxide/tin dioxide nanocomposite using sol-gel method, and then, the controlled release of imipenem from the double metal oxide/bioactive glass nanocomposite, and finally, the investigation of the antibacterial property of the nanocomposite. against a number of implant-related infectious agents. In this study, BG/SnO2 and BG/NiO single systema with different metal oxide present and BG/NiO/SnO2 nanocomposites were synthesized by sol-gel as drug carriers for tetracycline and imepinem. These two antibiotics were widely used for osteomyelitis because of its favorable penetration and bactericidal effect on all the probable osteomyelitis pathogens. The antibacterial activity of synthesized samples were evaluated against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa as bacteria model using disk diffusion method. The BG modification using metal oxides results to antibacterial property of samples containing metal oxide with highest efficiency for nancomposite. bioactivity of all samples was assessed by determining the surface morphology, structural and composition changes using scanning electron microscopy (SEM), FTIR and X-ray diffraction (XRD) spectroscopy, respectively, after soaking in simulated body fluid (SBF) for 28 days. The hydroxyapatite formation was clearly observed as a bioactivity measurement. Then, BG nanocomposite sample was loaded using two antibiotics, separately and their release profiles were studied. The BG nancomposite sample was shown the slow and continuous drug releasing for a period of 72 hours which is desirable for a drug delivery system. The loaded antibiotic nanocomposite sample retaining antibacterial property and showing inactivation effect against bacteria under test. The modified bioactive glass forming hydroxyapatite with controlled release drug and effective against bacterial infections can be introduced as scaffolds for bone implants after clinical trials for biomedical applications . Considering the formation of biofilm by infectious bacteria after sticking on the surfaces of implants, medical devices, etc. Also, considering the complications of traditional methods, solving the problems caused by the above-mentioned microorganisms in technical and biomedical industries was one of the necessities of this research.

Keywords: antibacterial, bioglass, drug delivery system, sol- gel

Procedia PDF Downloads 23

Authors: Chun-Liang Wu, Kai-Ping Shaw, Cheng-Ping Yu, Wu-Chien Chien, Hsiao-Ting Chen, Shao-Huang Wu

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Objective: This study analyzed three criminal judicial cases. We applied the patterned injuries of the rider to demonstrate the facts of each accident, reconstruct the scenes, and pursue the truth. Methods: Case analysis, a method that collects evidence and reasons the results in judicial procedures, then the importance of the pattern of injury as evidence will be compared and evaluated. The patterned injuries analysis method is to compare the collision situation between an object and human body injuries to determine whether the characteristics can reproduce the unique pattern of injury. Result: Case 1: Two motorcycles, A and B, head-on collided; rider A dead, and rider B was accused. During the prosecutor’s investigation, the defendant learned that rider A had an 80 mm open wound on his neck. During the court trial, the defendant requested copies of the case file and found out that rider A had a large contusion on his chest wall, and the cause of death was traumatic hemothorax and abdominal wall contusion. The defendant compared all the evidence at the scene and determined that the injury was obviously not caused by the collision of the body or the motorcycle of rider B but that rider was out of control and injured himself when he crossed the double yellow line. In this case, the defendant was innocent in the High Court judgment in April 2022. Case 2: Motorcycles C and D head-on crashed, and rider C died of massive abdominal bleeding. The prosecutor decided that rider C was driving under the influence (DUI), but rider D was negligent and sued rider D. The defendant requested the copies’ file and found the special phenomenon that the front wheel of motorcycle C was turned left. The defendant’s injuries were a left facial bone fracture, a left femur fracture, and other injuries on the left side. The injuries were of human-vehicle separation and human-vehicle collision, which proved that rider C suddenly turned left when the two motorcycles approached, knocked down motorcycle D, and the defendant flew forward. Case 3: Motorcycle E and F’s rear end collided, the front rider E was sentenced to 3 months, and the rear rider F sued rider E for more than 7 million N.T. The defendant found in the copies’ file that the injury of rider F was the left tibial platform fracture, etc., and then proved that rider F made the collision with his left knee, causing motorcycle E to fall out of control. This evidence was accepted by the court and is still on trial. Conclusion: The application of patterned injuries in the reconstruction of a motorcycle accident could discover the truth and provide the basis for judicial justice. The cases and methods could be the reference for the policy of preventing traffic accident casualties.

Keywords: judicial evidence, patterned injuries analysis, accident reconstruction, fatal motorcycle injuries

Procedia PDF Downloads 51

Authors: Ivana Scidà, Francesco Alotto, Anna Osello

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Due to the importance given today to innovation, the education sector is evolving thanks digital technologies. Virtual Reality (VR) can be a potential teaching tool offering many advantages in the field of training and education, as it allows to acquire theoretical knowledge and practical skills using an immersive experience in less time than the traditional educational process. These assumptions allow to lay the foundations for a new educational environment, involving and stimulating for students. Starting from the objective of strengthening the innovative teaching offer and the learning processes, the case study of the research concerns the digitalization of MastrLAB, High Quality Laboratory (HQL) belonging to the Department of Structural, Building and Geotechnical Engineering (DISEG) of the Polytechnic of Turin, a center specialized in experimental mechanical tests on traditional and innovative building materials and on the structures made with them. The MastrLAB-VR has been developed, a revolutionary innovative training tool designed with the aim of educating the class in total safety on the techniques of use of machinery, thus reducing the dangers arising from the performance of potentially dangerous activities. The virtual laboratory, dedicated to the students of the Building and Civil Engineering Courses of the Polytechnic of Turin, has been projected to simulate in an absolutely realistic way the experimental approach to the structural tests foreseen in their courses of study: from the tensile tests to the relaxation tests, from the steel qualification tests to the resilience tests on elements at environmental conditions or at characterizing temperatures. The research work proposes a methodology for the virtualization of technical laboratories through the application of Building Information Modelling (BIM), starting from the creation of a digital model. The process includes the creation of an independent application, which with Oculus Rift technology will allow the user to explore the environment and interact with objects through the use of joypads. The application has been tested in prototype way on volunteers, obtaining results related to the acquisition of the educational notions exposed in the experience through a virtual quiz with multiple answers, achieving an overall evaluation report. The results have shown that MastrLAB-VR is suitable for both beginners and experts and will be adopted experimentally for other laboratories of the University departments.

Keywords: building information modelling, digital learning, education, virtual laboratory, virtual reality

Procedia PDF Downloads 105

Authors: Padma Chutoo, Elena Kulinskaya, Ilyas Bakbergenuly, Nicholas Steel, Dmitri Pchejetski

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Transient ischaemic attacks (TIAs) are warning signs for future strokes. TIA patients are at increased risk of stroke and cardio-vascular events after a first episode. A majority of studies on TIA focused on the occurrence of these ancillary events after a TIA. Long-term mortality after TIA received only limited attention. We undertook this study to determine the long-term hazards of all-cause mortality following a first episode of a TIA using anonymised electronic health records (EHRs). We used a retrospective case-control study using electronic primary health care records from The Health Improvement Network (THIN) database. Patients born prior to or in year 1960, resident in England, with a first diagnosis of TIA between January 1986 and January 2017 were matched to three controls on age, sex and general medical practice. The primary outcome was all-cause mortality. The hazards of all-cause mortality were estimated using a time-varying Weibull-Cox survival model which included both scale and shape effects and a random frailty effect of GP practice. 20,633 cases and 58,634 controls were included. Cases aged 39 to 60 years at the first TIA event had the highest hazard ratio (HR) of mortality compared to matched controls (HR = 3.04, 95% CI (2.91 - 3.18)). The HRs for cases aged 61-70 years, 71-76 years and 77+ years were 1.98 (1.55 - 2.30), 1.79 (1.20 - 2.07) and 1.52 (1.15 - 1.97) compared to matched controls. Aspirin provided long-term survival benefits to cases. Cases aged 39-60 years on aspirin had HR of 0.93 (0.84 - 1.00), 0.90 (0.82 - 0.98) and 0.88 (0.80 - 0.96) at 5 years, 10 years and 15 years, respectively, compared to cases in the same age group who were not on antiplatelets. Similar beneficial effects of aspirin were observed in other age groups. There were no significant survival benefits with other antiplatelet options. No survival benefits of antiplatelet drugs were observed in controls. Our study highlights the excess long-term risk of death of TIA patients and cautions that TIA should not be treated as a benign condition. The study further recommends aspirin as the better option for secondary prevention for TIA patients compared to clopidogrel recommended by NICE guidelines. Management of risk factors and treatment strategies should be important challenges to reduce the burden of disease.

Keywords: dual antiplatelet therapy (DAPT), General Practice, Multiple Imputation, The Health Improvement Network(THIN), hazard ratio (HR), Weibull-Cox model

Procedia PDF Downloads 122

Authors: Agnieszka Antończyk, MałGorzata Ochota, Wojciech Niżański, ZdzisłAw Kiełbowicz

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The goal of the cesarean section (CS) is the delivery of healthy, vigorous pups with the provision of surgical plane anesthesia, appropriate analgesia, and rapid recovery of the dam. In human medicine, spinal or epidural anesthesia is preferred for a cesarean section as associated with a lower risk of neonatal asphyxia and the need for resuscitation. Nevertheless, the specificity of veterinary patients makes the application of regional anesthesia as a sole technique impractical, thus to obtain patient compliance the general anesthesia is required. This study aimed to compare the influence of balanced (inhalant with epidural) and inhalant anesthesia on neonatal umbilical cord blood gas (UCBG) parameters and vitality (modified Apgar scoring). The bitches (31) undergoing elective CS were enrolled in this study. All females received a single dose of 0.2 mg/kg s.c. Meloxicam. Females were randomly assigned into two groups: Gr I (Isoflurane, n=16) and Gr IE (Isoflurane plus Epidural, n=15). Anesthesia was induced with propofol at 4-6 mg/kg to effect, and maintained with isoflurane in oxygen; in IE group epidural anesthesia was also done using lidocaine (3-4 mg/kg) into the lumbosacral space. CSs were performed using a standard mid-line approach. Directly after the puppy extraction, the umbilical cord was double clamped before the placenta detachment. The vessels were gently stretched between forceps to allow blood sampling. At least 100 mcl of mixed umbilical cord blood was collected into a heparinized syringe for further analysis. The modified Apgar scoring system (AS) was used to objectively score neonatal health and vitality immediately after birth (before first aid or neonatal care was instituted), at 5 and 20 min after birth. The neonates were scored as normal (AS 7-10), weak (AS 4-6), or critical (AS 0-3). During surgery, the IE group required a lower isoflurane concentration compared to the females in group I (MAC 1.05±0.2 and 1.4±0.13, respectively, p<0.01). All investigated UCBG parameters were not statistically different between groups. All pups had mild acidosis (pH 7.21±0.08 and 7.21±0.09 in Gr I and IE, respectively) with moderately elevated pCO2 (Gr I 57.18±11.48, Gr IE 58.74±15.07), HCO3- on the lower border (Gr I 22.58±3.24, Gr IE 22.83±3.6), lowered BE (Gr I -6.1±3.57, Gr IE -5.6±4.19) and mildly elevated level of lactates (Gr I 2.58±1.48, Gr IE2.53±1.03). The glucose levels were above the reference limits in both groups of puppies (74.50±25.32 in Gr I, 79.50±29.73 in Gr IE). The initial Apgar score results were similar in I and IE groups. However, the subsequent measurements of AS revealed significant differences between both groups. Puppies from the IE group received better AS scores at 5 and 20 min compared to the I group (6.86±2.23 and 8.06±2.06 vs 5.11±2.40 and 7.83±2.05, respectively). The obtained results demonstrated that administration of epidural anesthesia reduced the requirement for isoflurane in dams undergoing cesarean section and did not affect the neonatal umbilical blood gas results. Moreover, newborns from the epidural anesthesia group were scored significantly higher in AS at 5 and 20 min, indicating their better vitality and quicker improvement post-surgery.

Keywords: apgar scoring, balanced anesthesia, cesarean section, umbilical blood gas

Procedia PDF Downloads 152

Authors: Anna Mirczak

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Introduction: In connection with the aging of the population and the increase in the number of people with chronic illnesses, the priority objective for public health has become not only lengthening life, but also improving quality of life in older persons, as well as maintenance of their relative independence and active participation in social life. The most important determinant of a person’s quality of life is health. According to the literature, older people with chronic illness who live in rural settings are at greater risk for poor outcomes than their urban counterparts. Furthermore research characterizes the rural elderly as having a higher incidence of sickness, dysfunction, disability, restricted mobility, and acute and chronic conditions than their urban citizens. It is dictated by the overlapping certain specific socio-economic factors typical for rural areas which include: social and geography exclusion, limited access to health care centers, and low socioeconomic status. Aim of the study: The objective of this study was to recognize health status and needs of older people living in selected rural areas in Poland and evaluate the impacts of working in the farm on their health status. Material and methods: The study was performed personally, using interviews based on the structural questionnaires, during the period from March 2011 to October 2012. The group of respondents consisted 203 people aged 65 years and over living in selected rural areas in Poland. The analysis of collected research material was performed using the statistical package SPSS 19 for Windows. The level of significance for the tested the hypotheses assumed value of 0.05. Results: The mean age of participants was 75,5 years (SD=5,7) range from 65 to 94 years. Most of the interviewees had children (89.2%) and grandchildren (83.7) and lived mainly with family members (75.9%) mostly in double (46.8%) and triple (20.8%) household. The majority of respondents (71,9%) were physical working on the farm. At the time of interview, each of the respondents reported that they had been diagnosed with at least one chronic diseases by their GP. The most common were: hypertension (67,5%), osteoarthritis (44,8%), atherosclerosis (43,3%), cataract (40,4%), arrhythmia (28,6%), diabetes mellitus (19,7%) and stomach or duodenum ulcer diseases (17,2%).The number of diseases occurring of the sample was dependent on gender and age. Significant associations were observed between working on the farm and frequency of occurrence cardiovascular diseases, the gastrointestinal tract dysfunction and sensory disorders. Conclusions: The most common causes of disability among older citizens were: chronic diseases, malnutrition and complaints about access to health services (especially to cardiologist and an ophthalmologist). Health care access and health status are a particular concern in rural areas where the population is older, has lower education and income levels, and is more likely to be living in medically underserved areas than is the case in urban areas.

Keywords: ageing, health status, older people, rural

Procedia PDF Downloads 245

Authors: Marzieh Ahmadi, Ruhullah Alikhan Gorgani

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The usual methods of measuring regional inequalities can not reflect the internal changes of the country in terms of their displacement in different development groups, and the indicators of inequalities are not effective in demonstrating the dynamics of the distribution of inequality. For this purpose, this paper examines the dynamics of the urban inertial transport in the country during the period of 2006-2016 using the CIRD multidimensional index and stochastic kernel density method. it firstly selects 25 indicators in five dimensions including macroeconomic conditions, science and innovation, environmental sustainability, human capital and public facilities, and two-stage Principal Component Analysis methodology are developed to create a composite index of inequality. Then, in the second stage, using a nonparametric analytical approach to internal distribution dynamics and a stochastic kernel density method, the convergence hypothesis of the CIRD index of the Iranian provinces center is tested, and then, based on the ergodic density, long-run equilibrium is shown. Also, at this stage, for the purpose of adopting accurate regional policies, the distribution dynamics and process of convergence or divergence of the Iranian provinces for each of the five. According to the results of the first Stage, in 2006 & 2016, the highest level of development is related to Tehran and zahedan is at the lowest level of development. The results show that the central cities of the country are at the highest level of development due to the effects of Tehran's knowledge spillover and the country's lower cities are at the lowest level of development. The main reason for this may be the lack of access to markets in the border provinces. Based on the results of the second stage, which examines the dynamics of regional inequality transmission in the country during 2006-2016, the first year (2006) is not multifaceted and according to the kernel density graph, the CIRD index of about 70% of the cities. The value is between -1.1 and -0.1. The rest of the sequence on the right is distributed at a level higher than -0.1. In the kernel distribution, a convergence process is observed and the graph points to a single peak. Tends to be a small peak at about 3 but the main peak at about-0.6. According to the chart in the final year (2016), the multidimensional pattern remains and there is no mobility in the lower level groups, but at the higher level, the CIRD index accounts for about 45% of the provinces at about -0.4 Take it. That this year clearly faces the twin density pattern, which indicates that the cities tend to be closely related to each other in terms of development, so that the cities are low in terms of development. Also, according to the distribution dynamics results, the provinces of Iran follow the single-density density pattern in 2006 and the double-peak density pattern in 2016 at low and moderate inequality index levels and also in the development index. The country diverges during the years 2006 to 2016.

Keywords: Urban Disparity, CIRD Index, Convergence, Distribution Dynamics, Random Kernel Density

Procedia PDF Downloads 98

Authors: Marita Heyns

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Job insecurity is a distressing phenomenon which has far reaching consequences for both employees and their organizations. Previously, much attention has been given to the link between job insecurity and individual level performance outcomes, while less is known about how subjectively perceived job insecurity might transfer beyond the individual level to affect performance of the organization on an aggregated level. Research focusing on how employees’ fear of job loss might affect the organization’s ability to respond proactively to volatility and drastic change through applying its capabilities of sensing, seizing, and reconfiguring, appears to be practically non-existent. Equally little is known about the potential underlying mechanisms through which job insecurity might affect the dynamic capabilities of an organization. This study examines how job insecurity might affect dynamic organizational capability through trust as an underling process. More specifically, it considered the simultaneous roles of trust at an impersonal (organizational) level as well as trust at an interpersonal level (in leaders and co-workers) as potential underlying mechanisms through which job insecurity might affect the organization’s dynamic capability to respond to opportunities and imminent, drastic change. A quantitative research approach and a stratified random sampling technique enabled the collection of data among 314 managers at four different plant sites of a large South African steel manufacturing organization undergoing dramatic changes. To assess the study hypotheses, the following statistical procedures were employed: Structural equation modelling was performed in Mplus to evaluate the measurement and structural models. The Chi-square values test for absolute fit as well as alternative fit indexes such as the Comparative Fit Index and the Tucker-Lewis Index, the Root Mean Square Error of Approximation and the Standardized Root Mean Square Residual were used as indicators of model fit. Composite reliabilities were calculated to evaluate the reliability of the factors. Finally, interaction effects were tested by using PROCESS and the construction of two-sided 95% confidence intervals. The findings indicate that job insecurity had a lower-than-expected detrimental effect on evaluations of the organization’s dynamic capability through the conducive buffering effects of trust in the organization and in its leaders respectively. In contrast, trust in colleagues did not seem to have any noticeable facilitative effect. The study proposes that both job insecurity and dynamic capability can be managed more effectively by also paying attention to factors that could promote trust in the organization and its leaders; some practical recommendations are given in this regard.

Keywords: dynamic organizational capability, impersonal trust, interpersonal trust, job insecurity

Procedia PDF Downloads 52

Authors: Lahari Ramya Pa, Sudhakar Ib, Madhu Vc, Madhusudhan Reddy Gd, Srinivasa Rao E.

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Selection of suitable armor materials for defense applications is very crucial with respect to increasing mobility of the systems as well as maintaining safety. Therefore, determining the material with the lowest possible areal density that resists the predefined threat successfully is required in armor design studies. A number of light metal and alloys are come in to forefront especially to substitute the armour grade steels. AA5083 aluminium alloy which fit in to the military standards imposed by USA army is foremost nonferrous alloy to consider for possible replacement of steel to increase the mobility of armour vehicles and enhance fuel economy. Growing need of AA5083 aluminium alloy paves a way to develop supplement aluminium alloys maintaining the military standards. It has been witnessed that AA 2xxx aluminium alloy, AA6xxx aluminium alloy and AA7xxx aluminium alloy are the potential material to supplement AA5083 aluminium alloy. Among those cited aluminium series alloys AA7xxx aluminium alloy (heat treatable) possesses high strength and can compete with armour grade steels. Earlier investigations revealed that layering of AA7xxx aluminium alloy can prevent spalling of rear portion of armour during ballistic impacts. Hence, present investigation deals with fabrication of hard layer (made of boron carbide) i.e. layer on AA 7075 aluminium alloy using friction stir processing with an intention of blunting the projectile in the initial impact and backing tough portion(AA7xxx aluminium alloy) to dissipate residual kinetic energy. An analytical approach has been adopted to unfold the ballistic performance of projectile. Penetration of projectile inside the armour has been resolved by considering by strain energy model analysis. Perforation shearing areas i.e. interface of projectile and armour is taken in to account for evaluation of penetration inside the armour. Fabricated surface composites (targets) were tested as per the military standard (JIS.0108.01) in a ballistic testing tunnel at Defence Metallurgical Research Laboratory (DMRL), Hyderabad in standardized testing conditions. Analytical results were well validated with experimental obtained one.

Keywords: AA7075 aluminium alloy, friction stir processing, boron carbide, ballistic performance, target

Procedia PDF Downloads 299

Authors: W. S. Mohamed, A. A. Hammam

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Sandy soils under arid and semi-arid conditions are characterized by poor physical and biochemical properties such as low water retention, rapid organic matter decomposition, low nutrients use efficiency, and limited crop productivity. Addition of organic amendments is crucial to develop soil properties and consequently enhance nutrients use efficiency and lessen organic carbon decomposition. Two years field experiments were developed to investigate the feasibility of using poultry manure and its derived biochar integrated with different levels of N fertilizer as a soil amendment for newly reclaimed sandy soils in Western Desert of El-Minia Governorate, Egypt. Results of this research revealed that poultry manure and its derived biochar addition induced pronounced effects on soil moisture content at saturation point, field capacity (FC) and consequently available water. Data showed that application of poultry manure (PM) or PM-derived biochar (PMB) in combination with inorganic N levels had caused significant changes on a range of the investigated sandy soil biochemical properties including pH, EC, mineral N, dissolved organic carbon (DOC), dissolved organic N (DON) and quotient DOC/DON. Overall, the impact of PMB on soil physical properties was detected to be superior than the impact of PM, regardless the inorganic N levels. In addition, the obtained results showed that PM and PM application had the capacity to stimulate vigorous growth, nutritional status, production levels of wheat and sorghum, and to increase soil organic matter content and N uptake and recovery compared to control. By contrast, comparing between PM and PMB at different levels of inorganic N, the obtained results showed higher relative increases in both grain and straw yields of wheat in plots treated with PM than in those treated with PMB. The interesting feature of this research is that the biochar derived from PM increased treated sandy soil organic carbon (SOC) 1.75 times more than soil treated with PM itself at the end of cropping seasons albeit double-applied amount of PM. This was attributed to the higher carbon stability of biochar treated sandy soils increasing soil persistence for carbon decomposition in comparison with PM labile carbon. It could be concluded that organic manures applied to sandy soils under arid and semi-arid conditions are subjected to high decomposition and mineralization rates through crop seasons. Biochar derived from organic wastes considers as a source of stable carbon and could be very hopeful choice for substituting easily decomposable organic manures under arid conditions. Therefore, sustainable agriculture and productivity in newly reclaimed sandy soils desire one high rate addition of biochar derived from organic manures instead of frequent addition of such organic amendments.

Keywords: biochar, dissolved organic carbon, N-uptake, poultry, sandy soil

Procedia PDF Downloads 121

Authors: Robel Wondimu Alemayehu, Sihwa Jung, Manwoo Park, Young K. Ju

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Following the aftermath of the 1994 Northridge earthquake, intensive research on beam to column connections is conducted, leading to the current design basis. The current design codes require the use of either a prequalified connection or a connection that passes the requirements of large-scale cyclic qualification test prior to use in intermediate or special moment frames. The second alternative is expensive both in terms of money and time. On the other hand, the maximum beam depth in most of the prequalified connections is limited to 900mm due to the reduced rotation capacity of deeper beams. However, for long span beams the need to use deeper beams may arise. In this study, a beam to column connection detail suitable for deep beams is presented. The connection detail comprises of thicker-tapered beam flange adjacent to the beam to column connection. Within the thicker-tapered flange region, two reduced beam sections are provided with the objective of forming two plastic hinges within the tapered-thicker flange region. In addition, the length, width, and thickness of the tapered-thicker flange region are proportioned in such a way that a third plastic hinge forms at the end of the tapered-thicker flange region. As a result, the total rotation demand is distributed over three plastic zones. Making it suitable for deeper beams that have lower rotation capacity at one plastic hinge. The effectiveness of this connection detail is studied through finite element analysis. For the study, a beam that has a depth of 1200mm is used. Additionally, comparison with welded unreinforced flange-welded web (WUF-W) moment connection and reduced beam section moment connection is made. The results show that the rotation capacity of a WUF-W moment connection is increased from 2.0% to 2.2% by applying the proposed moment connection detail. Furthermore, the maximum moment capacity, energy dissipation capacity and stiffness of the WUF-W moment connection is increased up to 58%, 49%, and 32% respectively. In contrast, applying the reduced beam section detail to the same WUF-W moment connection reduced the rotation capacity from 2.0% to 1.50% plus the maximum moment capacity and stiffness of the connection is reduced by 22% and 6% respectively. The proposed connection develops three plastic hinge regions as intended and it shows improved performance compared to both WUF-W moment connection and reduced beam section moment connection. Moreover, the achieved rotation capacity satisfies the minimum required for use in intermediate moment frames.

Keywords: connections, finite element analysis, seismic design, steel intermediate moment frame

Procedia PDF Downloads 142

Authors: Julia Cristina Bonaldo, Christophe L. Martin, Severine Romero Baivier, Stephane Mazerat

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Alumina refractories are commonly used in steel and foundry industries. These refractories are prepared through a powder metallurgy route. They are a mixture of hard alumina particles and graphite platelets embedded into a soft carbonic matrix (binder). The powder can be cold pressed isostatically or uniaxially, depending on the application. The compact is then fired to obtain the final product. The quality of the product is governed by the microstructure of the composite and by the process parameters. The compaction behavior and the mechanical properties of the fired product depend greatly on the amount of each phase, on their morphology and on the initial microstructure. In order to better understand the link between these parameters and the macroscopic behavior, we use the Discrete Element Method (DEM) to simulate the compaction process and the fracture behavior of the fired composite. These simulations are coupled with well-designed experiments. Four mixes with various amounts of Al₂O₃ and binder were tested both experimentally and numerically. In DEM, each particle is modelled and the interactions between particles are taken into account through appropriate contact or bonding laws. Here, we model a bimodal mixture of large Al₂O₃ and small Al₂O₃ covered with a soft binder. This composite is itself mixed with graphite platelets. X-ray tomography images are used to analyze the morphologies of the different components. Large Al₂O₃ particles and graphite platelets are modelled in DEM as sets of particles bonded together. The binder is modelled as a soft shell that covers both large and small Al₂O₃ particles. When two particles with binder indent each other, they first interact through this soft shell. Once a critical indentation is reached (towards the end of compaction), hard Al₂O₃ - Al₂O₃ contacts appear. In accordance with experimental data, DEM simulations show that the amount of Al₂O₃ and the amount of binder play a major role for the compaction behavior. The graphite platelets bend and break during the compaction, also contributing to the macroscopic stress. Firing step is modeled in DEM by ascribing bonds to particles which contact each other after compaction. The fracture behavior of the compacted mixture is also simulated and compared with experimental data. Both diametrical tests (Brazilian tests) and triaxial tests are carried out. Again, the link between the amount of Al₂O₃ particles and the fracture behavior is investigated. The methodology described here can be generalized to other particulate materials that are used in the ceramic industry.

Keywords: cold compaction, composites, discrete element method, refractory materials, x-ray tomography

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Authors: Yuanyuan Liu, Yuanqing Wang, Di Li

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Carbon dioxide (CO2) emissions mitigation from road construction activities is one of the potential pathways to deal with climate change due to its higher use of materials, machinery energy consumption, and high quantity of vehicle and equipment fuels for transportation and on-site construction activities. Aiming to assess the environmental impact of the road infrastructure construction activities and to identify hotspots of emissions sources, this study developed a life-cycle CO2 emissions assessment framework covering three stages of material production, to-site and on-site transportation under the guidance of the principle of LCA ISO14040. Then streamlined inventory analysis on sub-processes of each stage was conducted based on the budget files from cases of highway projects in China. The calculation results were normalized into functional unit represented as ton per km per lane. Then a comparison between the amount of emissions from each stage, and sub-process was made to identify the major contributor in the whole highway lifecycle. In addition, the calculating results were used to be compared with results in other countries for understanding the level of CO2 emissions associated with Chinese road infrastructure in the world. The results showed that materials production stage produces the most of the CO2 emissions (for more than 80%), and the production of cement and steel accounts for large quantities of carbon emissions. Life cycle CO2 emissions of fuel and electric energy associated with to-site and on-site transportation vehicle and equipment are a minor component of total life cycle CO2 emissions from highway project construction activities. Bridges and tunnels are dominant large carbon contributor compared to the road segments. The life cycle CO2 emissions of road segment in highway project in China are slightly higher than the estimation results of highways in European countries and USA, about 1500 ton per km per lane. In particularly, the life cycle CO2 emissions of road pavement in majority cities all over the world are about 500 ton per km per lane. However, there is obvious difference between the cities when the estimation on life cycle CO2 emissions of highway projects included bridge and tunnel. The findings of the study could offer decision makers a more comprehensive reference to understand the contribution of road infrastructure to climate change, especially understand the contribution from road infrastructure construction activities in China. In addition, the identified hotspots of emissions sources provide the insights of how to reduce road carbon emissions for development of sustainable transportation.

Keywords: carbon dioxide emissions, construction activities, highway, life cycle assessment

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Authors: Robertson Freeman

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The prime objective of this research is to examine income inequality and its effects on household livelihoods in Parker Paint. Many researchers failed to address the potential threat of income inequality on diverse household livelihood indicators, including health, food, housing, transport and many others. They examine and generalize the effects of income differentials on household livelihoods by addressing one indicator of livelihood security. This research fills the loopholes of previous research by examining the effects of income inequality and how it affects the livelihoods of households, taking into consideration livelihood indicators including health, food security, and transport. The researcher employed the mixed research method to analyze the distribution of income and solicit opinions of household heads on the effects of their monthly income on their livelihoods. Age and sex structure, household composition, type of employment and educational status influence income inequality. The level of income, Lorenz curve and the Gini coefficient was mutually employed to calculate and determine the level of income inequality. One hundred eighty-two representing 96% of household heads are employed while 8, representing 4%, are unemployed. However, out of a total number of 182 employed, representing 96%, 27 people representing 14%, are employed in the formal private sector, while 110, representing 58%, are employed in the private informal sector. Monthly average income, savings, investments and unexpected circumstances affect the livelihood of households. Infrastructural development and wellbeing should be pursued by reducing expenditure earmarked in other sectors and channeling the funds towards the provision of household needs. One of the potent tools for consolidating household livelihoods is to initiate livelihood empowerment programs. Government and private sector agencies should establish more health insurance schemes, providing mosquito nets, immunization services, public transport, as well as embarking on feeding programs, especially in the remote areas of Parker paint. To climax the research findings, self-employment, entrepreneurship and the general private sector employment is a transparent double-edged sword. If employed in the private sector, there is the likelihood to increase one’s income. However, this also induces the income gap between the rich and poor since many people are exploited by affluence, thereby relegating the poor from the wealth hierarchy. Age and sex structure, as well as type of employment, should not be overlooked since they all play fundamental roles in influencing income inequality. Savings and investments seem to play a positive role in reducing income inequality. However, savings and investment in this research affect livelihoods negatively. It behooves mankind to strive and work hard to the best of ability in earning sufficient income and embracing measures to retain his financial strength. In so doing, people will be able to provide basic household needs, celebrate the reduction in unemployment and dependence and finally ensure sustainable livelihoods.

Keywords: income, inequality, livelihood, pakerpaint

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Authors: J. D. Temperman

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Introduction: In particular, in relation to religion, the meaning and scope of freedom of expression have been tested in recent times. This paper investigates the legal justifications for restrictions that have been suggested in this area and asks whether they are sustainable from an international human rights perspective. The universal human rights instruments, particularly the UN International Covenant on Civil and Political Rights (ICCPR), are increasingly geared towards eradicating ‘incitement’ to contingent harms like violence or discrimination, whilst forms of extreme speech that fall short of such incitement are to be protected rather than countered by states. Human Rights Committee’s draft-General Comment on freedom of expression, adopted in 2011, provides another strong indication that this is the envisaged way forward: repealing anti-blasphemy and anti-religious defamation laws, whilst simultaneously increasing efforts to combat ‘incitement’. Within regional human rights frameworks, notably the European Convention system, judgments have in fact supported legal restrictions on both hate speech, holocaust denial, and blasphemy or religious defamation. Major contributions to scholarship: This paper proposes an actus reus for the offense of ‘advocacy of religious hatred that constitutes incitement to discrimination or violence’, as enshrined in Article 20(2) of the UN ICCPR. In underscoring the high threshold of ‘incitement’, the author distinguishes this offense from such notions as ‘blasphemy’ or ‘defamation of religions’. In addition to treating the said provision as a sui generis prohibition, the question is addresses whether a ‘right to be protected against incitement’ may be distilled from the ICCPR. Furthermore, the author will discuss the question of how to judge incitement; notably, is mens rea required to convict someone of incitement, and if so, what degree of mens rea? This analysis also includes the question how to balance content and context factors when addressing alleged instances of incitement, notably what factors make provide for a likelihood that imminent acts of violence or discrimination will ensue from an inciteful speech act? Methodology: This paper takes a double comparative approach: (i) it endeavours to compare and contrast monitoring bodies’ approach to incitement (notably, the UN Human Rights Committee, but also the UN Committee on the Elimination of Racial Discrimination which monitors states’ compliance with Article 4 of ICERD on incitement); and (ii) it endeavours to chart and compare and analyse from an international human rights perspective recent forms of state practice in the field of dealing with incitement (i.e. a comparative legal analysis and vertical human rights analysis of newly emerging incitement legislation in the light of the said international standards). Conclusion: This paper conceptualizes a legal notion – ‘incitement’ – encapsulated in international human rights law that may have a profound bearing on contemporary challenges of radicalization and religious strife.

Keywords: incitement, international human rights law, religious hatred, violence

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Authors: Darko Prebežac, Josip Mikulić, Maja Šerić, Damir Krešić

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Camping tourism is recognized as a growing segment of the broader tourism industry, currently evolving from an inexpensive, temporary sojourn in a rural environment into a highly fragmented niche tourism sector. The trends among public-managed campgrounds seem to be moving away from rustic campgrounds that provide only a tent pad and a fire ring to more developed facilities that offer a range of different amenities, where campers still search for unique experiences that go above the opportunity to experience nature and social interaction. In addition, while camping styles and options changed significantly over the last years, coastal camping in particular became valorized as is it regarded with a heightened sense of nostalgia. Alongside this growing interest in the camping tourism, a demand for quality servicing infrastructure emerged in order to satisfy the wide variety of needs, wants, and expectations of an increasingly demanding traveling public. However, camping activity in general and quality of camping experience and campers’ satisfaction in particular remain an under-researched area of the tourism and consumption behavior literature. In this line, very few studies addressed the issue of quality product/service provision in satisfying nature based tourists and in driving their future behavior with respect to potential re-visitation and recommendation intention. The present study thus aims to investigate the drivers of positive and negative campsite experience using the case of Croatia. Due to the well-preserved nature and indented coastline, camping tourism has a long tradition in Croatia and represents one of the most important and most developed tourism products. During the last decade the number of tourist overnights in Croatian camps has increased by 26% amounting to 16.5 million in 2014. Moreover, according to Eurostat the market share of campsites in the EU is around 14%, indicating that the market share of Croatian campsites is almost double large compared to the EU average. Currently, there are a total of 250 camps in Croatia with approximately 75.8 thousands accommodation units. It is further noteworthy that Croatian camps have higher average occupancy rates and a higher average length of stay as compared to the national average of all types of accommodation. In order to explore the main drivers of positive and negative campsite experiences, this study uses principal components analysis (PCA) and an impact-asymmetry analysis (IAA). Using the PCA, first the main dimensions of the campsite experience are extracted in an exploratory manner. Using the IAA, the extracted factors are investigated for their potentials to create customer delight and/or frustration. The results provide valuable insight to both researchers and practitioners regarding the understanding of campsite satisfaction.

Keywords: Camping tourism, campsite, impact-asymmetry analysis, satisfaction

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Authors: Bjorn Kierulf, Arun Chundru

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Over the past decade, collegiate rocketry teams have emerged across the country with various goals: space, liquid-fueled flight, etc. A critical piece of the development of knowledge within a club is the use of so-called "sounding rockets," whose goal is to take in-flight measurements that inform future rocket design. Common measurements include acceleration from inertial measurement units (IMU's), and altitude from barometers. With a properly tuned filter, these measurements can be used to find velocity, but are susceptible to noise, offset, and filter settings. Instead, velocity can be measured more directly and more instantaneously using a pitot tube, which operates by measuring the stagnation pressure. At supersonic speeds, an additional thermodynamic property is necessary to constrain the upstream state. One possibility is the stagnation temperature, measured by a thermocouple in the pitot tube. The routing of the pitot tube from the nosecone tip down to a pressure transducer is complicated by the nosecone's structure. Commercial-off-the-shelf (COTS) nosecones come with a removable metal tip (without a pitot tube). This provides the opportunity to make custom tips with integrated measurement systems without making the nosecone from scratch. The main design constraint is how the nosecone tip is held down onto the nosecone, using the tension in a threaded rod anchored to a bulkhead below. Because the threaded rod connects into a threaded hole in the center of the nosecone tip, the pitot tube follows a winding path, and the pressure fitting is off-center. Two designs will be presented in the paper, one with a curved pitot tube and a coaxial design that eliminates the need for the winding path by routing pressure through a structural tube. Additionally, three manufacturing methods will be presented for these designs: bound powder filament metal 3D printing, stereo-lithography (SLA) 3D printing, and traditional machining. These will employ three different materials, copper, steel, and proprietary resin. These manufacturing methods and materials are relatively low cost, thus accessible to student researchers. These designs and materials cover multiple use cases, based on how fast the sounding rocket is expected to travel and how important heating effects are - to measure and to avoid melting. This paper will include drawings showing key features and an overview of the design changes necessitated by the manufacture. It will also include a look at the successful use of these nosecone tips and the data they have gathered to date.

Keywords: additive manufacturing, machining, pitot tube, sounding rocketry

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Authors: Qi Peng

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The Chinese sport sector is currently undergoing a dramatic institutional change. A sport system that was heavily dominated by the government is starting to shift towards one that is driven by the market. During the past sixty years, the Chinese Football Association (CFA), although ostensibly a ‘non-governmental organization’, has been in fact operated under the close supervision and control of the government. The double-identity of CFA has taken most of the blame for the poor performance of the Chinese football team, especially the men’s team. In 2015, a policy initiated by the Chinese government introduced a potentially radical change to the institutional structure of CFA by delegating the power of government agency – the General Administration of Sport of China - to the organization (CFA) itself. Against such background, an overarching research question was brought up- will an organization remained institutionalized within the system change in response to the external (policy) jolt? To answer this question, three principal data collection methods were employed: document review, participant observation and semi-structured interviews. Document review provides the mapping of the structural and cultural framework in which the CFA functions during the change process. The author have had the chance to interact closely with the organization as participant observer in the organization for a period of time, long enough to collect the data, but never too long to get biased view of the situation. This stage enables the author to gain an in-depth understanding of how CFA managed to restructure the governance and legitimacy. Conducting semi-structured interviews with staff within the CFA and from staff within selected stakeholders of CFA also provided a crucial step to gain an insight into the factors for change as well as the implications of the change. A wide range of interviewees that have been and to be interviewed include: CFA members (senior officials and staff); local football associations members; senior Chinese Super League football club managers; CFA Super League Co., LTD (senior officials and staff); CSL broadcasters; Chinese Olympic Committee members. The preliminary research data shows that the CFA is currently undergoing two levels of change: although the settings of CFA has been gradually restructured (organizational framework), the organizational values and beliefs remain almost the same as the CFA before the reform. This means that the plan of shifting from a governmental agency to an autonomous association is an going process, and that organizational core beliefs and values are more difficult to change than its structural framework. This is due to the inertia of the organizational history and the effect of institutionalization. The change of Chinese Football Association is looked at as a pioneering sport organization in China to undertake the “decoupling” road. It is believed that many other sport organizations, especially sport governing bodies will follow the step of CFA in the near future. Therefore, the experience of CFA change is worthy of studying.

Keywords: Chinese Football Association, Organizational Change, Organizational Culture, Structural Framework

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Authors: Elena Chernyak

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The status of Russian women has changed dramatically over the course of Russian history and under different leadership and economic, political, and social conditions. The perception of women, their submissive roles, and low social status cause gender conflict that affects society: demographical issues, increased numbers of divorces, alcoholism, drug abuse, and crime. Despite the fact that around the world women are becoming more independent, protected by law, and play more important roles in society, Russian women are still dependent on men financially, socially, and psychologically. This paper critically explores the experience of Russian women over the course of over a thousand year of Russian history and how the position and image of women changed in Russian Empire, Soviet and post-Soviet Russia and what role women play in contemporary Russia. This paper is a result of deep examination of historical and religious literature, mass media, internet sources, and documents. This analysis shows that throughout history, the role and image of women in society have repeatedly varied depending on ideological and social conditions. In particular, the history of Russian women may be divided into five main periods. The first was the period of paganism, when almost all areas of life were open for women and when women were almost equal in social roles with men. During the second period, starting with the beginning of the Mongol invasion in the 13th century, the position of women was diminishing due to social transformation to the patriarchal society in which women started playing subordinate role in family and society. The third period – the period from the fourteenth through the sixteenth centuries - is a period of the total seclusion of Russian women from each part of social life. The fourth, Soviet period started after the Revolution of 1917. During that time, the position of women was drastically changed due to the transformation of traditional gender roles under the Bolshevik government. Woman's role was seen as worker-mothers who had a double duty: a worker and a mother. The final period began after the collapse of the Soviet Union. The restructuring (Perestroika) and post-Restructuring periods have had contradictory consequences and tremendous impact on Russian society. The image of women as partners and equal to men, which was promoted during the Soviet regime, has been replaced with the traditional functionalist views on family and the role of women, in which men and women have different but supposedly complementary roles. Modern Russia, despite publicly stating its commitment to equal rights, during last two decades has been reverting to an older social model with its emphasis on traditional gender roles, patriarchal ideas of dominant masculinity, and adverse attitudes to women, which are further supported and reinforced by the reviving Russian Orthodox Church. As demonstrated in this review, Russian women have never possessed the same rights as men and have always been subordinate to men. During all period of Russian history, patriarchal ideology maintained and reinforced in Russian society has always subjected women to manipulation, oppression, and victimization and portrayed women as not a ‘full human being’.

Keywords: women, Russia, patriarchy, religion, Russian Orthodox Church

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Authors: Youval Aberman, Jason E. Plaks

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This research provides initial evidence that self-efficacy of mitigation behavior – the belief that one’s action can make a difference on the environment – can be implicitly inferred from the way numerical information is presented in environmental messages. The scientific community sees climate change as a pressing issue, but the general public tends to construe climate change as an abstract phenomenon that is psychologically distant. As such, a main barrier to pro-environmental behavior is that individuals often believe that their own behavior makes little to no difference on the environment. When it comes to communicating how the behavior of billions of individuals affects global climate change, it might appear valuable to aggregate those billions and present the shocking enormity of the resources individuals consume. This research provides initial evidence that, in fact, this strategy is ineffective; presenting large-scale aggregate data dilutes the contribution of the individual and impedes individuals’ motivation to act pro-environmentally. The high-impact, underrepresented behavior of eating a sustainable diet was chosen for the present studies. US Participants (total N = 668) were recruited online for a study on ‘meat and the environment’ and received information about some of resources used in meat production – water, CO2e, and feed – with numerical information that varied in its frame of reference. A ‘Nation’ frame of reference discussed the resources used in the beef industry, such as the billions of CO2e released daily by the industry, while a ‘Meal’ frame of reference presented the resources used in the production of a single beef dish. Participants completed measures of pro-environmental attitudes and behavioral intentions, either immediately (Study 1) or two days (Study 2) after reading the information. In Study 2 (n = 520) participants also indicated whether they consumed less or more meat than usual. Study 2 included an additional control condition that contained no environmental data. In Study 1, participants who read about meat production at a national level, compared to at a meal level, reported lower motivation to make ecologically conscious dietary choices and reported lower behavioral intention to change their diet. In Study 2, a similar pattern emerged, with the added insight that the Nation condition, but not the Meal condition, deviated from the control condition. Participants across conditions, on average, reduced their meat consumption in the duration of Study 2, except those in the Nation condition who remained unchanged. Presenting nation-wide consequences of human behavior is a double-edged sword: Framing in a large scale might reveal the relationship between collective actions and environmental issues, but it hinders the belief that individual actions make a difference.

Keywords: climate change communication, environmental concern, meat consumption, motivation

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Authors: Youlu Huang, Huanjun Jiang

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A large number of old masonry buildings built in the last century still remain in the city. It generates the problems of unsafety, obsolescence, and non-habitability. In recent years, many old buildings have been reconstructed through renovating façade, strengthening, and adding floors. However, most projects only provide a solution for a single problem. It is difficult to comprehensively solve problems of poor safety and lack of building functions. Therefore, a comprehensive functional renovation program of adding reinforced concrete frame story at the bottom via integrally lifting the building and then strengthening the building was put forward. Based on field measurement and YJK calculation software, the seismic performance of an actual three-story masonry structure in Shanghai was identified. The results show that the material strength of masonry is low, and the bearing capacity of some masonry walls could not meet the code requirements. The elastoplastic time history analysis of the structure was carried out by using SAP2000 software. The results show that under the 7 degrees rare earthquake, the seismic performance of the structure reaches 'serious damage' performance level. Based on the code requirements of the stiffness ration of the bottom frame (lateral stiffness ration of the transition masonry story and frame story), the bottom frame story was designed. The integral lifting process of the masonry building was introduced based on many engineering examples. The reinforced methods for the bottom frame structure strengthened by the steel-reinforced mesh mortar surface layer (SRMM) and base isolators, respectively, were proposed. The time history analysis of the two kinds of structures, under the frequent earthquake, the fortification earthquake, and the rare earthquake, was conducted by SAP2000 software. For the bottom frame structure, the results show that the seismic response of the masonry floor is significantly reduced after reinforced by the two methods compared to the masonry structure. The previous earthquake disaster indicated that the bottom frame is vulnerable to serious damage under a strong earthquake. The analysis results showed that under the rare earthquake, the inter-story displacement angle of the bottom frame floor meets the 1/100 limit value of the seismic code. The inter-story drift of the masonry floor for the base isolated structure under different levels of earthquakes is similar to that of structure with SRMM, while the base-isolated program is better to protect the bottom frame. Both reinforced methods could significantly improve the seismic performance of the bottom frame structure.

Keywords: old buildings, adding story, seismic strengthening, seismic performance

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Authors: Ahmed Tamer AlMotasem, Jens Bergström, Anders Gåård, Pavel Krakhmalev, Thijs Jan Holleboom

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In sheet metal forming processes, accumulation and transfer of sheet material to tool surfaces, often referred to as galling, is the major cause of tool failure. Initiation of galling is assumed to occur due to local adhesive wear between two surfaces. Therefore, reducing adhesion between the tool and the work sheet has a great potential to improve the tool materials galling resistance. Experimental observations and theoretical studies show that the presence of primary micro-sized carbides and/or nitrides in alloyed steels may significantly improve galling resistance. Generally, decreased adhesion between the ceramic precipitates and the sheet material counter-surface are attributed as main reason to the latter observations. On the other hand, adhesion processes occur at an atomic scale and, hence, fundamental understanding of galling can be obtained via atomic scale simulations. In the present study, molecular dynamics simulations are used, with utilizing second nearest neighbor embedded atom method potential to investigate the influence of nano-sized cementite precipitates embedded in tool atoms. The main aim of the simulations is to gain new fundamental knowledge on galling initiation mechanisms. Two tool/work piece configurations, iron/iron and iron-cementite/iron, are studied under dry sliding conditions. We find that the average frictional force decreases whereas the normal force increases for the iron-cementite/iron system, in comparison to the iron/iron configuration. Moreover, the average friction coefficient between the tool/work-piece decreases by about 10 % for the iron-cementite/iron case. The increase of the normal force in the case of iron-cementite/iron system may be attributed to the high stiffness of cementite compared to bcc iron. In order to qualitatively explain the effect of cementite on adhesion, the adhesion force between self-mated iron/iron and cementite/iron surfaces has been determined and we found that iron/cementite surface exhibits lower adhesive force than that of iron-iron surface. The variation of adhesion force with temperature was investigated up to 600 K and we found that the adhesive force, generally, decreases with increasing temperature. Structural analyses show that plastic deformation is the main deformation mechanism of the work-piece, accompanied with dislocations generation.

Keywords: adhesion, cementite, galling, molecular dynamics

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Authors: C. A. Sharma, Birendra P. Singh

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We recovered 40 well preserved ribbon-shaped, meandering specimens of S. ningqiangensis from the Earthy Dolomite Member (Krol Group) and calcareous siltstone beds of the Earthy Siltstone Member (Tal Group) showing closely spaced annulations that lacked branching. The beginning and terminal points are indistinguishable. In certain cases, individual specimens are characterized by irregular, low-angle to high-angle sinuosity. It has been variously described as body fossil, ichnofossil and algae. Detailed study of this enigmatic fossil is needed to resolve the long standing controversy regarding its phylogenetic and stratigraphic placements, which will be an important contribution to the evolutionary history of metazoans. S. ningqiangensis has been known from the late Neoproterozoic (Ediacaran) of southern and central China (Sichuan, Shaanxi, Quinghai and Guizhou provinces and Ningxia Hui Autonomous region), Siberian platform and across Pc/C Boundary from latest Neoprterozoic to earliest Cambrian of northern India. Shaanxilithes is considered an Ediacaran organism that spans the Precambrian–Cambrian boundary, an interval marked by significant taphonomic and ecological transformations that include not only innovation but also probable extinction. All the past well constrained finds of S. ningqiangensis are restricted to Ediacaran age. However, due to the new recoveries of the fossil from Nigalidhar Syncline, the stratigraphic status of S. ningqiangensis-bearing Earthy Siltstone Member of the Shaliyan Formation of the Tal Group (Cambrian) is rendered uncertain, though the overlying Chert Member in the adjoining Korgai Syncline has yielded definite early Cambrian acritarchs. The moot question is whether the Earthy Siltstone Member represents an Ediacaran or an early Cambrian age?. It would be interesting to find if Shaanxilithes, so far known from Ediacaran sequences, could it transgress to the early Cambrian or in simple words could it withstand the Pc/C Boundary event? GC-MS data shows the S. ningqiangensis structure is formed by hydrocarbon organic compounds which are filled with inorganic elements filler like silica, Calcium, phosphorus etc. The S. ningqiangensis structure is a mixture of organic compounds of high molecular weight, containing several saturated rings with hydrocarbon chains having an occasional isolated carbon-carbon double bond and also containing, in addition, to small amounts of nitrogen, sulfur and oxygen. Data also revealed that the presence of nitrogen which would be either in the form of peptide chains means amide/amine or chemical form i.e. nitrates/nitrites etc. The formula weight and the weight ratio of C/H shows that it would be expected for algae derived organics, since algae produce fatty acids as well as other hydrocarbons such as cartenoids.

Keywords: GC-MS Analysis, lesser himalaya, Pc/C Boundary, shaanxilithes

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Authors: Evy Van Puymbroeck, Wim Nagy, Ken Schotte, Heng Fang, Hans De Backer

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The knowledge of residual stresses for welded bridge components is essential to determine the effect of the residual stresses on the fatigue life behavior. The residual stresses of an orthotropic bridge deck are determined by simulating the welding process with finite element modelling. The stiffener is placed on top of the deck plate before welding. A chained thermal-mechanical analysis is set up to determine the distribution of residual stresses for the bridge deck. First, a thermal analysis is used to determine the temperatures of the orthotropic deck for different time steps during the welding process. Twin wire submerged arc welding is used to construct the orthotropic plate. A double ellipsoidal volume heat source model is used to describe the heat flow through a material for a moving heat source. The heat input is used to determine the heat flux which is applied as a thermal load during the thermal analysis. The heat flux for each element is calculated for different time steps to simulate the passage of the welding torch with the considered welding speed. This results in a time dependent heat flux that is applied as a thermal loading. Thermal material behavior is specified by assigning the properties of the material in function of the high temperatures during welding. Isotropic hardening behavior is included in the model. The thermal analysis simulates the heat introduced in the two plates of the orthotropic deck and calculates the temperatures during the welding process. After the calculation of the temperatures introduced during the welding process in the thermal analysis, a subsequent mechanical analysis is performed. For the boundary conditions of the mechanical analysis, the actual welding conditions are considered. Before welding, the stiffener is connected to the deck plate by using tack welds. These tack welds are implemented in the model. The deck plate is allowed to expand freely in an upwards direction while it rests on a firm and flat surface. This behavior is modelled by using grounded springs. Furthermore, symmetry points and lines are used to prevent the model to move freely in other directions. In the thermal analysis, a mechanical material model is used. The calculated temperatures during the thermal analysis are introduced during the mechanical analysis as a time dependent load. The connection of the elements of the two plates in the fusion zone is realized with a glued connection which is activated when the welding temperature is reached. The mechanical analysis results in a distribution of the residual stresses. The distribution of the residual stresses of the orthotropic bridge deck is compared with results from literature. Literature proposes uniform tensile yield stresses in the weld while the finite element modelling showed tensile yield stresses at a short distance from the weld root or the weld toe. The chained thermal-mechanical analysis results in a distribution of residual weld stresses for an orthotropic bridge deck. In future research, the effect of these residual stresses on the fatigue life behavior of welded bridge components can be studied.

Keywords: finite element modelling, residual stresses, thermal-mechanical analysis, welding simulation

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Authors: Xiaoyong He

Abstract:

The manipulation of THz waves is still a challenging task due to lack of natural materials interacted with it strongly. Designed by tailoring the characters of unit cells (meta-molecules), the advance of metamaterials (MMs) may solve this problem. However, because of Ohmic and radiation losses, the performance of MMs devices is subjected to the dissipation and low quality factor (Q-factor). This dilemma may be circumvented by Fano resonance, which arises from the destructive interference between a bright continuum mode and dark discrete mode (or a narrow resonance). Different from symmetric Lorentz spectral curve, Fano resonance indicates a distinct asymmetric line-shape, ultrahigh quality factor, steep variations in spectrum curves. Fano resonance is usually realized through symmetry breaking. However, if concentric double rings (DR) are placed closely to each other, the near-field coupling between them gives rise to two hybridized modes (bright and narrowband dark modes) because of the local asymmetry, resulting into the characteristic Fano line shape. Furthermore, from the practical viewpoint, it is highly desirable requirement that to achieve the modulation of Fano spectral curves conveniently, which is an important and interesting research topics. For current Fano systems, the tunable spectral curves can be realized by adjusting the geometrical structural parameters or magnetic fields biased the ferrite-based structure. But due to limited dispersion properties of active materials, it is still a tough work to tailor Fano resonance conveniently with the fixed structural parameters. With the favorable properties of extreme confinement and high tunability, graphene is a strong candidate to achieve this goal. The DR-structure possesses the excitation of so-called “trapped modes,” with the merits of simple structure and high quality of resonances in thin structures. By depositing graphene circular DR on the SiO2/Si/ polymer substrate, the tunable Fano resonance has been theoretically investigated in the terahertz regime, including the effects of graphene Fermi level, structural parameters and operation frequency. The results manifest that the obvious Fano peak can be efficiently modulated because of the strong coupling between incident waves and graphene ribbons. As Fermi level increases, the peak amplitude of Fano curve increases, and the resonant peak position shifts to high frequency. The amplitude modulation depth of Fano curves is about 30% if Fermi level changes in the scope of 0.1-1.0 eV. The optimum gap distance between DR is about 8-12 μm, where the value of figure of merit shows a peak. As the graphene ribbon width increases, the Fano spectral curves become broad, and the resonant peak denotes blue shift. The results are very helpful to develop novel graphene plasmonic devices, e.g. sensors and modulators.

Keywords: graphene, metamaterials, terahertz, tunable

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Authors: A. Askerov, Y. Teterin, P. Yartcev, S. Novikov

Abstract:

Introduction: Acute pancreatitis (AP) is a socially significant problem for public health and continues to be one of the most common causes of hospitalization of patients with pathology of the gastrointestinal tract. It is characterized by high mortality rates, which reaches 62-65% in infected pancreatic necrosis. Aims & Methods: The study group included 63 patients who underwent transluminal drainage (TLD) fluid collection (FC). All patients were performed transabdominal ultrasound, computer tomography of the abdominal cavity and retroperitoneal organs and endoscopic ultrasound (EUS) of the pancreatobiliary zone. The EUS was used as a final diagnostic method to determine the characteristics of FC. The indications for TLD were: the distance between the wall of the hollow organ and the FC was not more than 1 cm, the absence of large vessels on the puncture trajectory (more than 3 mm), and the size of the formation was more than 5 cm. When a homogeneous cavity with clear, even contours was detected, a plastic stent with rounded ends (“double pig tail”) was installed. The indication for the installation of a fully covered self-expanding stent was the detection of nonhomogeneous anechoic FC with hyperechoic inclusions and cloudy purulent contents. In patients with necrotic forms after drainage of the purulent cavity, a cystonasal drainage with a diameter of 7Fr was installed in its lumen under X-ray control to sanitize the cavity with a 0.05% aqueous solution of chlorhexidine. Endoscopic necrectomy was performed every 24-48 hours. The plastic stent was removed in 6 month, the fully covered self-expanding stent - in 1 month after the patient was discharged from the hospital. Results: Endoscopic TLD was performed in 63 patients. The FC corresponding to interstitial edematous pancreatitis was detected in 39 (62%) patients who underwent TLD with the installation of a plastic stent with rounded ends. In 24 (38%) patients with necrotic forms of FC, a fully covered self-expanding stent was placed. Communication with the ductal system of the pancreas was found in 5 (7.9%) patients. They underwent pancreaticoduodenal stenting. A complicated postoperative period was noted in 4 (6.3%) cases and was manifested by bleeding from the zone of pancreatogenic destruction. In 2 (3.1%) cases, this required angiography and endovascular embolization a. gastroduodenalis, in 1 (1.6%) case, endoscopic hemostasis was performed by filling the cavity with 4 ml of Hemoblock hemostatic solution. The combination of both methods was used in 1 (1.6%) patient. There was no evidence of recurrent bleeding in these patients. Lethal outcome occurred in 4 patients (6.3%). In 3 (4.7%) patients, the cause of death was multiple organ failure, in 1 (1.6%) - severe nosocomial pneumonia that developed on the 32nd day after drainage. Conclusions: 1. EUS is not only the most important method for diagnosing FC in AP, but also allows you to determine further tactics for their intraluminal drainage.2. Endoscopic intraluminal drainage of fluid zones in 45.8% of cases is the final minimally invasive method of surgical treatment of large-focal pancreatic necrosis. Disclosure: Nothing to disclose.

Keywords: acute pancreatitis, fluid collection, endoscopy surgery, necrectomy, transluminal drainage

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Authors: Trevor Malambo Simbayi, Diane Hildebrandt, Tonderayi Matambo

Abstract:

The rapid growth of population in recent decades has resulted in an increased need for energy to meet human activities. As energy demands increase, the need for other sources of energy other than fossil fuels, increases in turn. Furthermore, environmental concerns such as global warming due to the use of fossil fuels, depleting fossil fuel reserves and the rising cost of oil have contributed to an increased interest in renewables sources of energy. Biogas is a renewable source of energy produced through the process of anaerobic digestion (AD) and it offers a two-fold solution; it provides an environmentally friendly source of energy and its production helps to reduce the amount of organic waste taken to landfills. This research seeks to address the waste management problem caused by an aquatic weed called water hyacinth (Eichhornia crassipes) at the Hartbeespoort (Harties) Dam in the North West Province of South Africa, through biogas production of the weed. Water hyacinth is a category 1 invasive species and it is deemed to be the most problematic aquatic weed. This weed is said to double its size in the space of five days. Eutrophication in the Hartbeespoort Dam has manifested itself through the excessive algae bloom and water hyacinth infestation. A large amount of biomass from water hyacinth and algae are generated per annum from the two hundred hectare surface area of the dam exposed to the sun. This biomass creates a waste management problem. Water hyacinth when in full bloom can cover nearly half of the surface of Hartbeespoort Dam. The presence of water hyacinth in the dam has caused economic and environmental problems. Economic activities such as fishing, boating, and recreation, are hampered by the water hyacinth’s prolific growth. This research proposes the use of water hyacinth as a feedstock or substrate for biogas production in order to find an economic and environmentally friendly means of waste management for the communities living around the Hartbeespoort Dam. In order to achieve this objective, water hyacinth will be collected from the dam and it will be mechanically pretreated before anaerobic digestion. Pretreatment is required for lignocellulosic materials like water hyacinth because such materials are called recalcitrant solid materials. Cow manure will be employed as a source of microorganisms needed for biogas production to occur. Once the water hyacinth and the cow dung are mixed, they will be placed in laboratory anaerobic reactors. Biogas production will be monitored daily through the downward displacement of water. Characterization of the substrates (cow manure and water hyacinth) to determine the nitrogen, sulfur, carbon and hydrogen, total solids (TS) and volatile solids (VS). Liquid samples from the anaerobic digesters will be collected and analyzed for volatile fatty acids (VFAs) composition by means of a liquid gas chromatography machine.

Keywords: anaerobic digestion, biogas, waste management, water hyacinth

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Authors: Evangelos G. Ilias, Panagiotis G. Ilias, Vasileios T. Popotas

Abstract:

The United Kingdom has one of the oldest railway networks in the world dating back to 1825 when the world’s first passenger railway was opened. The network has some 40,000 bridges of various construction types using a wide range of materials including masonry, steel, cast iron, wrought iron, concrete and timber. It is commonly accepted that the successful operation of the network is vital for the economy of the United Kingdom, consequently the cost effective maintenance of the existing infrastructure is a high priority to maintain the operability of the network, prevent deterioration and to extend the life of the assets. Every bridge on the railway network is required to be assessed every eighteen years and a structured approach to assessments is adopted with three main types of progressively more detailed assessments used. These assessment types include Level 0 (standardized spreadsheet assessment tools), Level 1 (analytical hand calculations) and Level 2 (generally finite element analyses). There is a degree of conservatism in the first two types of assessment dictated to some extent by the relevant standards which can lead to some structures not achieving the required load rating. In these situations, a Level 2 Assessment is often carried out using finite element analysis to uncover ‘latent strength’ and improve the load rating. If successful, the more sophisticated analysis can save on costly strengthening or replacement works and avoid disruption to the operational railway. This paper presents the ‘strengthening by assessment’ achieved by Level 2 analyses. The use of more accurate analysis assumptions and the implementation of non-linear modelling and functions (material, geometric and support) to better understand buckling modes and the structural behaviour of historic construction details that are not specifically covered by assessment codes are outlined. Metallic bridges which are susceptible to loss of section size through corrosion have largest scope for improvement by the Level 2 Assessment methodology. Three case studies are presented, demonstrating the effectiveness of the sophisticated Level 2 Assessment methodology using finite element analysis against the conservative approaches employed for Level 0 and Level 1 Assessments. One rail overbridge and two rail underbridges that did not achieve the required load rating by means of a Level 1 Assessment due to the inadequate restraint provided by U-Frame action are examined and the increase in assessed capacity given by the Level 2 Assessment is outlined.

Keywords: assessment, bridges, buckling, finite element analysis, non-linear modelling, strengthening

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