Search results for: independent variable
Commenced in January 2007
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Edition: International
Paper Count: 4079

Search results for: independent variable

1529 Spatiotemporal Variation Characteristics of Soil pH around the Balikesir City, Turkey

Authors: Çağan Alevkayali, Şermin Tağil

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Determination of soil pH surface distribution in urban areas is substantial for sustainable development. Changes on soil properties occur due to functions on performed in agriculture, industry and other urban functions. Soil pH is important to effect on soil productivity which based on sensitive and complex relation between plant and soil. Furthermore, the spatial variability of soil reaction is necessary to measure the effects of urbanization. The objective of this study was to explore the spatial variation of soil pH quality and the influence factors of human land use on soil Ph around Balikesir City using data for 2015 and Geographic Information Systems (GIS). For this, soil samples were taken from 40 different locations, and collected with the method of "Systematic Random" from the pits at 0-20 cm depths, because anthropologic sourced pollutants accumulate on upper layers of soil. The study area was divided into a grid system with 750 x 750 m. GPS was used to determine sampling locations, and Inverse Distance Weighting (IDW) interpolation technique was used to analyze the spatial distribution of pH in the study area and to predict the variable values of un-exampled places with the help from the values of exampled places. Natural soil acidity and alkalinity depend on interaction between climate, vegetation, and soil geological properties. However, analyzing soil pH is important to indirectly evaluate soil pollution caused by urbanization and industrialization. The result of this study showed that soil pH around the Balikesir City was neutral, in generally, with values were between 6.5 and 7.0. On the other hand, some slight changes were demonstrated around open dump areas and the small industrial sites. The results obtained from this study can be indicator of important soil problems and this data can be used by ecologists, planners and managers to protect soil supplies around the Balikesir City.

Keywords: Balikesir, IDW, GIS, spatial variability, soil pH, urbanization

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1528 Investigating of Predisposing Factors for Domestic Violence against Women

Authors: Mozhgan Sigarchian, Shiva Alizadeh, Seyedeh Akram Nazarkardeh

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Introduction: The one of the most common forms of violence against women is domestic violence and it is one of the most acute social problems that affecting the individual physical and mental health and, in turn, the health of the family and the community. In all of the world especially in developing country, women suffer violent during her lifetime. Violence against women and girls is a serious threat to health and human rights. Several factors such as low literacy, the low income and poverty affects violence. The purpose of this study was to determine the factors conducive to domestic violence against women in Rasht, Iran, So that based on the findings, preventive measures can be taken to reduce violence and increase support for women. Methods: This is a descriptive-analytic study that was performed on 300 eligible women referred to clinics and physicians' offices in Rasht, Iran, 2017, by convenience sampling method. The questionnaire used included demographic questionnaires and domestic violence with 3 domains: physical, psychological, and sexual violence. Data were analyzed by SPSS software using independent t-test, Chi-square and Mann-Whitney tests. Result: The mean age in the group with and without domestic violence was 28.31 ± 6.097 and 32.52 ± 9.8, respectively. 168 women (56%) were reported to be violent. The results indicate that there is a significant relationship between age, husband's age, number of family members, and educational level of women with violence. But, there was no significant relationship between the duration of marriage, the education of husbands, the occupation of women and their husbands, housing situation, smoking with violence. Conclusion: The results showed that some factors such as education, age, and the number of families can affect the level of violence. According to the results, as well as a high prevalence of domestic violence among women in this study, it is suggested that training be given to families to increase women's empowerment and prevent violence against women.

Keywords: domestic violence, predisposing factors, violence, women

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1527 Relationships of Driver Drowsiness and Sleep-Disordered Breathing Syndrome

Authors: Cheng-Yu Tsai, Wen-Te Liu, Yin-Tzu Lin, Chen-Chen Lo, Kang Lo

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Background: Driving drowsiness related to inadequate or disordered sleep accounts for a major percentage of traffic accidents. Sleep-disordered breathing (SDB) syndrome is a common respiratory disorder during sleep. However, the effects of SDB syndrome on driving fatigue remain unclear. Objective: This study aims to investigate the relationship between SDB pattern and driving drowsiness. Methodologies: The physical condition while driving was obtained from the questionnaires to classify the state of driving fatigue. SDB syndrome was quantified as the polysomnography, and the air flow pattern was collected by the thermistor and nasal pressure cannula. To evaluate the desaturation, the mean hourly number of greater than 3% dips in oxygen saturation was sentenced by reregistered technologist during examination in a hospital in New Taipei City (Taiwan). The independent T-test was used to investigate the correlations between sleep disorders related index and driving drowsiness. Results: There were 880 subjects recruited in this study, who had been done polysomnography for evaluating severity for obstructive sleep apnea syndrome (OSAS) as well as completed the driver condition questionnaire. Four-hundred-eighty-four subjects (55%) were classified as fatigue group, and 396 subjects (45%) were served as the control group. Significantly higher values of snoring index (242.14 ± 205.51 /hours) were observed in the fatigue group (p < 0.01). The value of respiratory disturbance index (RDI) (31.82 ± 19.34 /hours) in fatigue group were significantly higher than the control group (p < 0.01). Conclusion: We observe the considerable association between SDB syndrome and driving drowsiness. To promote traffic safety, SDB syndrome should be controlled and alleviated.

Keywords: driving drowsiness, sleep-disordered breathing syndrome, snoring index, respiratory disturbance index.

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1526 Effect of a Single Injection of hCG on Testosterone Concentration in Male Alpacas

Authors: A. ElZawam, D. McLean, A. Tibary

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In alpaca, age at puberty is variable and the factors regulating the pattern of puberty and sexual maturation are a subject of controversy. Plasma testosterone level is often used as an indicator of sexual maturity. Our hypothesis is that hCG treatment will cause an increase in testosterone level that is correlated with animal age. The specific aim was to investigate the testicular tissue response to a single hCG injection by monitoring the serum testosterone concentration. Eighty four (n=84) males ranging in age from 6 to 60 months were used. Alpacas were grouped based on their ages into 15 groups. Each group had three to five male animals. Blood samples were collected from the jugular vein before treatment with hCG and 2 hours after intravenous administration of 3000 IU of hCG (Chorulon®). The serum was harvested and stored at -20ºC until the analysis. The effect of age on basal testosterone level and response to hCG treatment was evaluated by Analysis of Variance. As a result, basal serum testosterone concentrations were very low (<0.1ng/ml) until 9 months of age. Although basal serum testosterone concentrations increased steadily with age there was a significant variation amongst males within the same age group. Administration of 3000 IU of hCG, resulted in an average increase of 50% (P<0.05) in serum testosterone concentration after 2 hours. The percentage increase in serum testosterone in response to hCG stimulation varied from 51 to 81%. There was no correlation between the degree of response and age. However, the response to hCG injection presented two modes of increase depending on the age of animals. The first mode occurred at ages 9 to 14 months and the second mode was observed between 22 and 36 months. In conclusion, our results suggest that testicular growth and sensitivity to LH stimulation may be bimodal in the male alpaca with a rapid increase in growth and sensitivity between 9 and 14 months of age and a second phase of increased responsiveness after 21 months of ages.

Keywords: alpaca, testosterone, hCG, animal science

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1525 Destination of the PhDs: Determinants of International Mobility of UK PhD Graduates

Authors: Anna Siuda-Bak

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This paper adopts a comparative approach to examining the determinants of international mobility of German, Italian and British researchers who completed their doctoral education in the UK. Structured sampling and data collection techniques have been developed in order to retrieve information on participants from publicly available sources. This systematically collected data was supplemented with an on-line survey which captures participants’ job trajectories, including movements between positions, institutions and countries. In total, data on 949 German, Italian and British PhDs was collected. Logistic regression was employed to identify factors associated with one’s probability of moving outside the UK after his or her graduation. The predictor variables included factors associated with one’s PhD (field of study, ranking of the university which awarded the PhD degree) and family factors (having a child, nationality of the partner). Then, 9 constrained models were estimated to test the effect each variable has on probability of going to a specific destination, being English-speaking country, non-English speaking country or returning to the home country. The results show that females, arts and humanities graduates, and respondents with a partner from the UK are less mobile than their counterparts. The effect of the ranking of the university differed in two groups. The UK graduates from higher ranked universities were more likely to move abroad than to stay in the UK after their graduation. In contrast, non-UK natives from the same universities were less likely to be internationally mobile than non-UK natives from lower ranked universities. The nationality of the partner was the most important predictor of the specific destination choices. Graduates with partner from the home county were more likely to return home and those with a partner from the third country least likely to return.

Keywords: doctoral graduates, international mobility, nationality, UK

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1524 Return on Investment of a VFD Drive for Centrifugal Pump

Authors: Benhaddadi M., Déry D.

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Electric motors are the single biggest consumer of electricity, and the consumption will have more than to double by 2050. Meanwhile, the existing technologies offer the potential to reduce the motor energy demand by up to 30 %, whereas the know-how to realise energy savings is not extensively applied. That is why the authors first conducted a detailed analysis of the regulation of the electric motor market in North America To illustrate the colossal energy savings potential permitted by the VFD, the authors have equipped experimental setup, based on centrifugal pump, simultaneously equipped with regulating throttle valves and variable frequency drive VFD. The obtained experimental results for 1.5 HP motor pump are extended to another motor powers, as centrifugal pumps that are different in power may have similar operational characteristics if they are located in a similar kind of process, permitting the simulations for 5 HP and 100 HP motors. According to the obtained results, VFDs tend to be most cost-effective when fitted to larger motor pumps, in addition to higher duty cycle of the motor and relative time operating at lower than full load. The energy saving permitted by the VFD use is huge, and the payback period for drive investment is short. Nonetheless, it’s important to highlight that there is no general rule of thumb that can be used to obtain the impact of the relative time operating at lower than full load. Indeed, in terms of energy-saving differences, 50 % flow regulation is tremendously better than 75 % regulation, but a slightly enhanced relative to 25 %. Two main distinct reasons can explain this somewhat not anticipated results: the characteristics of the process and the drop in efficiency when motor is operating at low speed.

Keywords: motor, drive, energy efficiency, centrifugal pump

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1523 Bio-Inspired Design Approach Analysis: A Case Study of Antoni Gaudi and Santiago Calatrava

Authors: Marzieh Imani

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Antoni Gaudi and Santiago Calatrava have reputation for designing bio-inspired creative and technical buildings. Even though they have followed different independent approaches towards design, the source of bio-inspiration seems to be common. Taking a closer look at their projects reveals that Calatrava has been influenced by Gaudi in terms of interpreting nature and applying natural principles into the design process. This research firstly discusses the dialogue between Biomimicry and architecture. This review also explores human/nature discourse during the history by focusing on how nature revealed itself to the fine arts. This is explained by introducing naturalism and romantic style in architecture as the outcome of designers’ inclination towards nature. Reviewing the literature, theoretical background and practical illustration of nature have been included. The most dominant practical aspects of imitating nature are form and function. Nature has been reflected in architectural science resulted in shaping different architectural styles such as organic, green, sustainable, bionic, and biomorphic. By defining a set of common aspects of Gaudi and Calatrava‘s design approach and by considering biomimetic design categories (organism, ecosystem, and behaviour as the main division and form, function, process, material, and construction as subdivisions), Gaudi’s and Calatrava’s project have been analysed. This analysis explores if their design approaches are equivalent or different. Based on this analysis, Gaudi’s architecture can be recognised as biomorphic while Calatrava’s projects are literally biomimetic. Referring to these architects, this review suggests a new set of principles by which a bio-inspired project can be determined either biomorphic or biomimetic.

Keywords: biomimicry, Calatrava, Gaudi, nature

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1522 Synthesis, Characterization and Catecholase Study of Novel Bidentate Schiff Base Derived from Dehydroacetic Acid

Authors: Salima Tabti, Chaima Maouche, Tinhinene Louaileche, Amel Djedouani, Ismail Warad

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Novel Schiff base ligand HL has been synthesized by condensation of aromatic amine and DHA. It was characterized by UV-Vis, FT-IR, SM, NMR (1H, 13C) and also by single-crystal X-ray diffraction. The crystal structure shows that compound crystallized in a triclinic system in P-1 space group and with a two unit per cell (Z = 2).The asymmetric unit, contains one independent molecules, the conformation is determined by an intermolecular N-H…O hydrogen bond with an S(6) ring motif. The molecule have an (E) conformation about the C=N bond. The dihedral angles between the phenyl and pyran ring planes is 89.37 (1), the two plans are approximately perpendicular. The catecholase activity of is situ copper complexes of this ligand has been investigated against catechol. The progress of the oxidation reactions was closely monitored over time following the strong peak of catechol using UV-Vis. Oxidation rates were determined from the initial slope of absorbance. time plots, then analyzed by Michaelis-Menten equations. Catechol oxidation reactions were realized using different concentrations of copper acetate and ligand (L/Cu: 1/1, 1/2, 2/1). The results show that all complexes were able to catalyze the oxidation of catechol. Acetate complexes have the highest activity. Catalysis is a branch of chemical kinetics that, more generally, studies the influence of all physical or chemical factors determining reaction rates. It solves a lot of problems in the chemistry reaction process, especially for a green, economic and less polluting chemistry. For this reason, the search for new catalysts for known organic reactions, occupies a very advanced place in the themes proposed by the chemists.

Keywords: dehydroacetic acid, catechol, copper, catecholase activity, x-ray

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1521 The Effects of Traditional Thai Massage Technique Delivered by Parents on Stereotypical Behaviors in Children with Autism: A Pilot Study

Authors: Chanada Aonsri, Wichai Eungpinichpong

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Stereotypical behavior is one of the learning and social skills development problems that affect children with autism. Previous studies found that traditional Thai massage (TTM) could reduce stereotypical behaviors in autistic children. However, the effects of TTM delivered by the parents of autistic children have not been explored. This pilot study investigated the effects of TTM by parents on stereotypical behaviors in children with autism. A one-group pretest-posttest design was applied for 15 children, aged 4-16 years, with their parents' permissions. They participated in the study at the Special Education program of the Special Education Center of Khon Kaen University, Thailand. After being trained in a specialized TTM for children, the parents delivered 50-minute TTM to children once a day, twice a week for eight weeks. The severity of autism and autistic behaviors were measured using the Childhood Autism Rating Scale (CARS), and the Autism Treatment Evaluation Checklist (ATEC), respectively. The functions of autonomic nervous systems were measured using Heart Rate Variability (HRV) to indicated physical and mental disorders such as stress. The data at baseline and the 8th week were analyzed using either an independent t-test or Wilcoxon signed-rank test. The study found that 16 sessions of TTM significantly improved measured data for autism in all children including the CARS (p<0.001), ATEC, speech/language/communication (p<0.001), sociability (p<0.001), sensory/cognitive awareness (p<0.001), health/physical/behavior (p < 0.001), and HRV (p<0.001). The results indicated that TTM performed by parents could be useful as an adjunct therapy for autistic children as it can reduce stereotypical behaviors and stress.

Keywords: traditional Thai massage, stereotypical behaviors, Autistic children, parent

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1520 Acoustic Emission Techniques in Monitoring Low-Speed Bearing Conditions

Authors: Faisal AlShammari, Abdulmajid Addali, Mosab Alrashed

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It is widely acknowledged that bearing failures are the primary reason for breakdowns in rotating machinery. These failures are extremely costly, particularly in terms of lost production. Roller bearings are widely used in industrial machinery and need to be maintained in good condition to ensure the continuing efficiency, effectiveness, and profitability of the production process. The research presented here is an investigation of the use of acoustic emission (AE) to monitor bearing conditions at low speeds. Many machines, particularly large, expensive machines operate at speeds below 100 rpm, and such machines are important to the industry. However, the overwhelming proportion of studies have investigated the use of AE techniques for condition monitoring of higher-speed machines (typically several hundred rpm, or even higher). Few researchers have investigated the application of these techniques to low-speed machines ( < 100 rpm). This paper addressed this omission and has established which, of the available, AE techniques are suitable for the detection of incipient faults and measurement of fault growth in low-speed bearings. The first objective of this paper program was to assess the applicability of AE techniques to monitor low-speed bearings. It was found that the measured statistical parameters successfully monitored bearing conditions at low speeds (10-100 rpm). The second objective was to identify which commonly used statistical parameters derived from the AE signal (RMS, kurtosis, amplitude and counts) could identify the onset of a fault in the out race. It was found that these parameters effectually identify the presence of a small fault seeded into the outer races. Also, it is concluded that rotational speed has a strong influence on the measured AE parameters but that they are entirely independent of the load under such load and speed conditions.

Keywords: acoustic emission, condition monitoring, NDT, statistical analysis

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1519 The Role of Privatization on the Formulation of Productive Supply Chain: The Case of Ethiopian Firms

Authors: Merhawit Fisseha Gebremariam, Yohannes Yebabe Tesfay

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This study focuses on the formulation of a sustainable, effective, and efficient supply chain strategy framework that will enable Ethiopian privatized firms. The study examined the role of privatization in productive sourcing, production, and delivery to Ethiopian firm’s performances. To analyze our hypothesis, the authors applied the concepts of Key Performance Indicator (KPI), strategic outsourcing, purchasing portfolio analysis, and Porter's marketing analysis. The authors selected ten privatized companies and compared their financial, market expansion, and sustainability performances. The Chi-Square Test showed that at the 5% level of significance, privatization and outsourcing activities can assist the business performances of Ethiopian firms in terms of product promotion and new market expansion. At the 5% level of significance, the independent t-test result showed that firms that were privatized by Ethiopian investors showed stronger financial performance than those that were privatized by foreign investors. Furthermore, it is better if Ethiopian firms apply both cost leadership and differentiated strategy to enhance thriving in their business area. Ethiopian firms need to implement the supply chain operations reference (SCOR) model for an exclusive framework that supports communication links the supply chain partners, and enhances productivity. The government of Ethiopia should be aware that the privatization of firms by Ethiopian investors will strengthen the economy. Otherwise, the privatization process will be risky for the country, and therefore, the government of Ethiopia should stop doing those activities.

Keywords: correlation analysis, market strategies, KPIs, privatization, risk and Ethiopia

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1518 Portable Palpation Probe for Diabetic Foot Ulceration Monitoring

Authors: Bummo Ahn

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Palpation is widely used to measure soft tissue firmness or stiffness in the living condition in order to apply detection, diagnosis, and treatment of tumors, scar tissue, abnormal muscle tone, or muscle spasticity. Since these methods are subjective and depend on the proficiency level, it is concluded that there are other diagnoses depending on the condition of the experts and the results are not objective. The mechanical property obtained by using the elasticity of the tissue is important to calculate a predictive variable for monitoring abnormal tissues. If the mechanical load such as reaction force on the foot increases in the same region under the same conditions, the mechanical property of the tissue is changed. Therefore, objective diagnosis is possible not only for experts but also for patients using this quantitative information. Furthermore, the portable system also allows non-experts to easily diagnose at home, not in hospitals or institutions. In this paper, we introduce a portable palpation system that can be used to measure the mechanical properties of human tissue, which can be applied to monitor diabetic foot ulceration patients with measuring the mechanical property change of foot tissue. The system was designed to be smaller and portable in comparison with the conventional palpation systems. It is consists of the probe, the force sensor, linear actuator, micro control unit, the display module, battery, and housing. Using this system, we performed validation experiments by applying different palpations (3 and 5 mm) to soft tissue (silicone rubber) and measured reaction forces. In addition, we estimated the elastic moduli of the soft tissue against different palpations and compare the estimated elastic moduli that show similar value even if the palpation depths are different.

Keywords: palpation probe, portable, diabetic foot ulceration, monitoring, mechanical property

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1517 The Issue of Pedagogical Approaches in Higher Education: Public Universities as an Example

Authors: Majda El Moufarej

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Higher education plays a central role in socio-economic development. However, with the wave of change mainly due to the extensive use of technology in the workplace, the rate of unemployment among graduates rises because they lack the appropriate competencies and skills currently required in professional life. This situation has led higher education institutions worldwide to reconsider their missions, strategic planning, and curricula, among other elements to redress the image of the university as expected. When it comes to practice, there are many obstacles that hinder the achievement of the expected objectives, especially in public universities with free access, as in the case of Morocco. Nevertheless, huge efforts have been made by educational managers to improve the quality of education by focusing on the issue of pedagogical approaches, where university teachers assume more responsibility to save the situation. In this paper, the focus will be placed on the issue of pedagogical approaches to be adopted, depending on the nature of the subject, the size of the class, the available equipment, the students’ level and degree of motivation. Before elaborating on this idea, it may be more insightful to begin by addressing another variable, which concerns the new role of university teachers and their qualification in pedagogical competence. Then, the discussion will revolve around five pedagogical approaches currently adopted in western universities and the focus will be exclusively placed on the one which is called “the Systematic Approach to course Design”, due to its crucial relevance in the teaching of subjects in the schools of humanities, as it can guide the teacher in the development of an explicit program for purposeful teaching and learning. The study is based on a qualitative method, and the findings will be analyzed and followed by some recommendations about how to overcome difficulties in teaching large groups, while transmitting the relevant knowledge and skills on demand in the workplace.

Keywords: higher education, public universities, pedagogical approaches, pedagogical competence

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1516 An Evaluation of Neuropsychiatric Manifestations in Systemic Lupus Erythematosus Patients in Saudi Arabia and Their Associated Factors

Authors: Yousef M. Alammari, Mahmoud A. Gaddoury, Reem A. Almohaini, Sara A. Alharbi, Lena S. Alsaleem, Lujain H. Allowaihiq, Maha H. Alrashid, Abdullah H. Alghamdi, Abdullah A. Alaryni

Abstract:

Objective: The goal of this study was to establish the prevalence of neuropsychiatric symptoms in systemic lupus erythematosus (NPSLE) patients in Saudi Arabia and the variables that are linked to it. Methods: During June 2021, this cross-sectional study was carried out among SLE patients in Saudi Arabia. The Saudi Rheumatism Association exploited social media platforms to provide a self-administered online questionnaire to SLE patients. All data analyses were performed using the Statistical Packages for Social Sciences (SPSS) version 26. Results: Two hundred and five SLE patients participated in the study (females 91.3 % vs. males 8.7 %). In addition, 13.5 % of patients had a family history of SLE, and 26% had SLE for one to three years. Alteration or loss of sensation (53.4%), Fear (52.4%), and headache (48.1%) were the most prevalent signs of neuropsychiatric symptoms in systemic lupus erythematosus (NPSLE) patients. The prevalence of patients with NPSLE was 40%. In a multivariate regression model, fear, altered sensations, cerebrovascular illness, sleep disruption, and diminished interest in routine activities were identified as independent risk variables for NPSLE. Conclusion: Nearly half of SLE patients demonstrated NP manifestations, with significant symptoms including fear, alteration of sensation, cerebrovascular disease, sleep disturbance, and reduced interest in normal activities. To detect the pathophysiology of NPSLE, it is necessary to understand the relationship between neuropsychiatric morbidity and other relevant rheumatic disorders in the SLE population.

Keywords: neuropsychiatric, systemic lupus erythematosus, NPSLE, prevalence, SLE patients

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1515 Study of the Effect of the Contra-Rotating Component on the Performance of the Centrifugal Compressor

Authors: Van Thang Nguyen, Amelie Danlos, Richard Paridaens, Farid Bakir

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This article presents a study of the effect of a contra-rotating component on the efficiency of centrifugal compressors. A contra-rotating centrifugal compressor (CRCC) is constructed using two independent rotors, rotating in the opposite direction and replacing the single rotor of a conventional centrifugal compressor (REF). To respect the geometrical parameters of the REF one, two rotors of the CRCC are designed, based on a single rotor geometry, using the hub and shroud length ratio parameter of the meridional contour. Firstly, the first rotor is designed by choosing a value of length ratio. Then, the second rotor is calculated to be adapted to the fluid flow of the first rotor according aerodynamics principles. In this study, four values of length ratios 0.3, 0.4, 0.5, and 0.6 are used to create four configurations CF1, CF2, CF3, and CF4 respectively. For comparison purpose, the circumferential velocity at the outlet of the REF and the CRCC are preserved, which means that the single rotor of the REF and the second rotor of the CRCC rotate with the same speed of 16000rpm. The speed of the first rotor in this case is chosen to be equal to the speed of the second rotor. The CFD simulation is conducted to compare the performance of the CRCC and the REF with the same boundary conditions. The results show that the configuration with a higher length ratio gives higher pressure rise. However, its efficiency is lower. An investigation over the entire operating range shows that the CF1 is the best configuration in this case. In addition, the CRCC can improve the pressure rise as well as the efficiency by changing the speed of each rotor independently. The results of changing the first rotor speed show with a 130% speed increase, the pressure ratio rises of 8.7% while the efficiency remains stable at the flow rate of the design operating point.

Keywords: centrifugal compressor, contra-rotating, interaction rotor, vacuum

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1514 CFD Analysis of the Blood Flow in Left Coronary Bifurcation with Variable Angulation

Authors: Midiya Khademi, Ali Nikoo, Shabnam Rahimnezhad Baghche Jooghi

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Cardiovascular diseases (CVDs) are the main cause of death globally. Most CVDs can be prevented by avoiding habitual risk factors. Separate from the habitual risk factors, there are some inherent factors in each individual that can increase the risk potential of CVDs. Vessel shapes and geometry are influential factors, having great impact on the blood flow and the hemodynamic behavior of the vessels. In the present study, the influence of bifurcation angle on blood flow characteristics is studied. In order to approach this topic, by simplifying the details of the bifurcation, three models with angles 30°, 45°, and 60° were created, then by using CFD analysis, the response of these models for stable flow and pulsatile flow was studied. In the conducted simulation in order to eliminate the influence of other geometrical factors, only the angle of the bifurcation was changed and other parameters remained constant during the research. Simulations are conducted under dynamic and stable condition. In the stable flow simulation, a steady velocity of 0.17 m/s at the inlet plug was maintained and in dynamic simulations, a typical LAD flow waveform is implemented. The results show that the bifurcation angle has an influence on the maximum speed of the flow. In the stable flow condition, increasing the angle lead to decrease the maximum flow velocity. In the dynamic flow simulations, increasing the bifurcation angle lead to an increase in the maximum velocity. Since blood flow has pulsatile characteristics, using a uniform velocity during the simulations can lead to a discrepancy between the actual results and the calculated results.

Keywords: coronary artery, cardiovascular disease, bifurcation, atherosclerosis, CFD, artery wall shear stress

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1513 Architecture for QoS Based Service Selection Using Local Approach

Authors: Gopinath Ganapathy, Chellammal Surianarayanan

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Services are growing rapidly and generally they are aggregated into a composite service to accomplish complex business processes. There may be several services that offer the same required function of a particular task in a composite service. Hence a choice has to be made for selecting suitable services from alternative functionally similar services. Quality of Service (QoS)plays as a discriminating factor in selecting which component services should be selected to satisfy the quality requirements of a user during service composition. There are two categories of approaches for QoS based service selection, namely global and local approaches. Global approaches are known to be Non-Polynomial (NP) hard in time and offer poor scalability in large scale composition. As an alternative to global methods, local selection methods which reduce the search space by breaking up the large/complex problem of selecting services for the workflow into independent sub problems of selecting services for individual tasks are coming up. In this paper, distributed architecture for selecting services based on QoS using local selection is presented with an overview of local selection methodology. The architecture describes the core components, namely, selection manager and QoS manager needed to implement the local approach and their functions. Selection manager consists of two components namely constraint decomposer which decomposes the given global or workflow level constraints in local or task level constraints and service selector which selects appropriate service for each task with maximum utility, satisfying the corresponding local constraints. QoS manager manages the QoS information at two levels namely, service class level and individual service level. The architecture serves as an implementation model for local selection.

Keywords: architecture of service selection, local method for service selection, QoS based service selection, approaches for QoS based service selection

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1512 Prediction of California Bearing Ratio of a Black Cotton Soil Stabilized with Waste Glass and Eggshell Powder using Artificial Neural Network

Authors: Biruhi Tesfaye, Avinash M. Potdar

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The laboratory test process to determine the California bearing ratio (CBR) of black cotton soils is not only overpriced but also time-consuming as well. Hence advanced prediction of CBR plays a significant role as it is applicable In pavement design. The prediction of CBR of treated soil was executed by Artificial Neural Networks (ANNs) which is a Computational tool based on the properties of the biological neural system. To observe CBR values, combined eggshell and waste glass was added to soil as 4, 8, 12, and 16 % of the weights of the soil samples. Accordingly, the laboratory related tests were conducted to get the required best model. The maximum CBR value found at 5.8 at 8 % of eggshell waste glass powder addition. The model was developed using CBR as an output layer variable. CBR was considered as a function of the joint effect of liquid limit, plastic limit, and plastic index, optimum moisture content and maximum dry density. The best model that has been found was ANN with 5, 6 and 1 neurons in the input, hidden and output layer correspondingly. The performance of selected ANN has been 0.99996, 4.44E-05, 0.00353 and 0.0067 which are correlation coefficient (R), mean square error (MSE), mean absolute error (MAE) and root mean square error (RMSE) respectively. The research presented or summarized above throws light on future scope on stabilization with waste glass combined with different percentages of eggshell that leads to the economical design of CBR acceptable to pavement sub-base or base, as desired.

Keywords: CBR, artificial neural network, liquid limit, plastic limit, maximum dry density, OMC

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1511 Performance and Emission Characteristics of Spark Ignition Engine Running with Gasoline, Blends of Ethanol, and Blends of Ethiopian Arekie

Authors: Mengistu Gizaw Gawo, Bisrat Yoseph Gebrehiwot

Abstract:

Petroleum fuels have become a threat to the world because of their toxic emissions. Besides, it is unknown how long they will last. The only known fact is that they are depleting rapidly and will not last long. So the world’s concern about finding environmentally friendly alternative fuels has increased recently. Hence alcohol fuels are found to be the most convenient alternatives to use in internal combustion engines. This research intends to introduce Ethiopian locally produced alcohol as an alternative in the blended form with gasoline to use in spark ignition engines. The traditionally distilled Arekie was purchased from a local producer and purified using fractional distillation. Then five Arekie-gasoline blends were prepared with the proportion of 5,10,15,20 and 25%v/v (A5, A10, A15, A20, and A25, respectively). Also, absolute ethanol was purchased from a local supplier, and ethanol-gasoline blends were prepared with a similar proportion as Arekie-gasoline blends (E5, E10, E15, E20, and E25). Then an experiment was conducted on a single-cylinder, 4-stroke, spark-ignition engine running at a constant speed of 2500 rpm and variable loads to investigate the performance and emission characteristics. Results showed that the performance and emission parameters are significantly improved as the ratio of Arekie and ethanol in gasoline increases at all loads. Among all tested fuels, E20 exhibited better performance, and E25 exhibited better emission. A20 provided a slightly lower performance than E20 but was much improved compared to pure gasoline. A25 provided comparable emissions with E25 and was much better than pure gasoline. Generally, adding up to 20%v/v Ethiopian Arekie in gasoline could make a better, renewable alternative to spark ignition engines.

Keywords: alcohol fuels, alternative fuels, pollutant emissions, spark-ignition engine, Arekie-gasoline blends

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1510 Bone Mineral Density in Type 2 Diabetes Mellitus Postmenopausal Egyptian Female Patients: Correlation with Fetuin-A Level and Metabolic Parameters

Authors: Ahmed A. M. Shoaib, Heba A. Esaily, Mahmoud M. Emara, Eman A. E. Badr, Amany S. Khalifa, Mayada M. M., Abdel-Raizk

Abstract:

Background: DM is associated with metabolic bone diseases, osteoporosis, low-impact fractures and falls in geriatrics. Fetuin-A, which is a serum protein produced by the liver and promotes bone mineralization, is an independent risk factor for type 2 diabetes. Aim: Evaluation of fetuin-A level and bone mineral density in postmenopausal Egyptian female patients with type 2 diabetes mellitus and their correlation with each other & with other metabolic parameters. Patients and methods: Seventy postmenopausal female patients with type II diabetes and thirty postmenopausal female as control were included in this study. Measurement of Fetuin-A together with metabolic parameters and DXA in wrist, hip and spine, ALP, CBC, FBS, PP2H and HBA1c was done in all participants. Results: - Fetuin-A level was found to be highly significant (p< 0.001) between diabetic and nondiabetic groups and negatively correlated with BMD in spine. No difference in BMD was found between patients and control groups while significant negative correlation was found between FBS and hip BMD (<0.05) and between 2hpp and HBA1c with spine BMD in the diabetic group (<0.05). Osteoporosis represented 12.9% in spine area and 7.2% in hip and wrist areas in diabetic patients, while osteopenia were found in 58.5%, 57.1%, and 37.1% in diabetic patients in spine, wrist, and hip respectively. Conclusion: - type II diabetes cannot be considered as a risk factor for osteoporosis; while glycemic parameters (FBS, 2hpp & HBA1c) and serum Fetuin-A levels were correlated with BMD in diabetics. Good glycemic control can be protective against osteoporosis in diabetic elderly.

Keywords: fetuin-A, BMD, postmenopausal, DM type II

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1509 The Curse of Natural Resources: An Empirical Analysis Applied to the Case of Copper Mining in Zambia

Authors: Chomba Kalunga

Abstract:

Many developing countries have a rich endowment of natural resources. Yet, amidst that wealth, living standards remain poor. At the same time, international markets have been surged with an increase in copper prices in the last twenty years. This is a presentation of the findings on the causal economic impact of Zambia’s copper mines, a country located in sub-Saharan Africa endowed with vast copper deposits on living standards using household data from 1996 to 2010, exploiting an episode where the copper prices on the international market were rising. Using an Instrumental Variable approach and controlling for constituency-level and microeconomic factors, the results show a significant impact of copper production on living standards. After splitting the constituencies close to and far away from the nearest mine, the results document that constituencies close to the mines benefited significantly from the increase in copper production, compared to their counterparts through increased levels of employment. Finally, the results are not consistent with the natural resource curse hypothesis; findings show a positive causal relationship between the presence of natural resources and socioeconomic outcomes in less developed countries, particularly for constituencies close to the mines in Zambia. Some key policy implications follow from the findings. The finding that increased copper production led to an increase in employment suggests that, in Zambias’ context, policies that promote local employment may be more beneficial to residents. Meaning that it is government policies that can help improve the living standards were government needs to work towards making this impact more substantial.

Keywords: copper prices, local development, mining, natural resources

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1508 Understanding Retail Benefits Trade-offs of Dynamic Expiration Dates (DED) Associated with Food Waste

Authors: Junzhang Wu, Yifeng Zou, Alessandro Manzardo, Antonio Scipioni

Abstract:

Dynamic expiration dates (DEDs) play an essential role in reducing food waste in the context of the sustainable cold chain and food system. However, it is unknown for the trades-off in retail benefits when setting an expiration date on fresh food products. This study aims to develop a multi-dimensional decision-making model that integrates DEDs with food waste based on wireless sensor network technology. The model considers the initial quality of fresh food and the change rate of food quality with the storage temperature as cross-independent variables to identify the potential impacts of food waste in retail by applying s DEDs system. The results show that retail benefits from the DEDs system depend on each scenario despite its advanced technology. In the DEDs, the storage temperature of the retail shelf leads to the food waste rate, followed by the change rate of food quality and the initial quality of food products. We found that the DEDs system could reduce food waste when food products are stored at lower temperature areas. Besides, the potential of food savings in an extended replenishment cycle is significantly more advantageous than the fixed expiration dates (FEDs). On the other hand, the information-sharing approach of the DEDs system is relatively limited in improving sustainable assessment performance of food waste in retail and even misleads consumers’ choices. The research provides a comprehensive understanding to support the techno-economic choice of the DEDs associated with food waste in retail.

Keywords: dynamic expiry dates (DEDs), food waste, retail benefits, fixed expiration dates (FEDs)

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1507 The Impact of the Enron Scandal on the Reputation of Corporate Social Responsibility Rating Agencies

Authors: Jaballah Jamil

Abstract:

KLD (Peter Kinder, Steve Lydenberg and Amy Domini) research & analytics is an independent intermediary of social performance information that adopts an investor-pay model. KLD rating agency does not have an explicit monitoring on the rated firm which suggests that KLD ratings may not include private informations. Moreover, the incapacity of KLD to predict accurately the extra-financial rating of Enron casts doubt on the reliability of KLD ratings. Therefore, we first investigate whether KLD ratings affect investors' perception by studying the effect of KLD rating changes on firms' financial performances. Second, we study the impact of the Enron scandal on investors' perception of KLD rating changes by comparing the effect of KLD rating changes on firms' financial performances before and after the failure of Enron. We propose an empirical study that relates a number of equally-weighted portfolios returns, excess stock returns and book-to-market ratio to different dimensions of KLD social responsibility ratings. We first find that over the last two decades KLD rating changes influence significantly and negatively stock returns and book-to-market ratio of rated firms. This finding suggests that a raise in corporate social responsibility rating lowers the firm's risk. Second, to assess the Enron scandal's effect on the perception of KLD ratings, we compare the effect of KLD rating changes before and after the Enron scandal. We find that after the Enron scandal this significant effect disappears. This finding supports the view that the Enron scandal annihilates the KLD's effect on Socially Responsible Investors. Therefore, our findings may question results of recent studies that use KLD ratings as a proxy for Corporate Social Responsibility behavior.

Keywords: KLD social rating agency, investors' perception, investment decision, financial performance

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1506 The Cloud Systems Used in Education: Properties and Overview

Authors: Agah Tuğrul Korucu, Handan Atun

Abstract:

Diversity and usefulness of information that used in education are have increased due to development of technology. Web technologies have made enormous contributions to the distance learning system especially. Mobile systems, one of the most widely used technology in distance education, made much easier to access web technologies. Not bounding by space and time, individuals have had the opportunity to access the information on web. In addition to this, the storage of educational information and resources and accessing these information and resources is crucial for both students and teachers. Because of this importance, development and dissemination of web technologies supply ease of access to information and resources are provided by web technologies. Dynamic web technologies introduced as new technologies that enable sharing and reuse of information, resource or applications via the Internet and bring websites into expandable platforms are commonly known as Web 2.0 technologies. Cloud systems are one of the dynamic web technologies that defined as a model provides approaching the demanded information independent from time and space in appropriate circumstances and developed by NIST. One of the most important advantages of cloud systems is meeting the requirements of users directly on the web regardless of hardware, software, and dealing with install. Hence, this study aims at using cloud services in education and investigating the services provided by the cloud computing. Survey method has been used as research method. In the findings of this research the fact that cloud systems are used such studies as resource sharing, collaborative work, assignment submission and feedback, developing project in the field of education, and also, it is revealed that cloud systems have plenty of significant advantages in terms of facilitating teaching activities and the interaction between teacher, student and environment.

Keywords: cloud systems, cloud systems in education, online learning environment, integration of information technologies, e-learning, distance learning

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1505 Preventive Behaviors of Exposure to ‎Secondhand Smoke among Women: A Study Based on the Health Belief Model

Authors: Arezoo Fallahi

Abstract:

Introduction: Exposure to second-hand smoke is an important global health problem and threatens the health of people, especially children and women. The aim of this study was to determine the effect of education based on the Health Belief Model on preventive behaviors of exposure to secondhand smoke in women. Materials and Methods: This experimental study was performed in 2023in Sanandaj, west of Iran. Seventy-four people were selected by simple random sampling and divided into an intervention group (37 people) and a control group (37 people). Data collection tools included demographic characteristics and a second-hand smoke exposure questionnaire based on the Health Beliefs Model. The training in the intervention group was conducted in three one-hour sessions in the comprehensive health service centers in the form of lectures, pamphlets, and group discussions. Data were analyzed using SPSS software version 21 and statistical tests such as correlation, paired t-test, and independent t-test. Results: The intervention and control groups were homogeneous before education. They were similar in terms of mean scores of the Health Belief Model. However, after an educational intervention, some of the scores increased, including the mean perceived sensitivity score (from 17.62±2.86 to 19.75±1.23), perceived severity score (28.40±4.45 to 31.64±2), perceived benefits score (27.27±4.89 to 31.94±2.17), practice score (32.64±4.68 to 36.91±2.32) perceived barriers from 26.62±5.16 to 31.29±3.34, guide for external action (from 17.70±3.99 to 22/89 ±1.67), guide for internal action from (16.59±2.95 to 1.03±18.75), and self-efficacy (from 19.83 ±3.99 to 23.37±1.43) (P <0.05). Conclusion: The educational intervention designed based on the Health Belief Model in women was effective in performing preventive behaviors against exposure to secondhand smoke.

Keywords: women, health behaviour, smoke, belive

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1504 A Literature Review on the Effect of Financial Knowledge toward Corporate Growth: The Important Role of Financial Risk Attitude

Authors: Risna Wijayanti, Sumiati, Hanif Iswari

Abstract:

This study aims to analyze the role of financial risk attitude as a mediation between financial knowledge and business growth. The ability of human resources in managing capital (financial literacy) can be a major milestone for a company's business to grow and build its competitive advantage. This study analyzed the important role of financial risk attitude in bringing about financial knowledge on corporate growth. There have been many discussions arguing that financial knowledge is one of the main abilities of corporate managers in determining the success of managing a company. However, a contrary argument of other scholars also enlightened that financial knowledge did not have a significant influence on corporate growth. This study used literatures' review to analyze whether there is another variable that can mediate the effect of financial knowledge toward corporate growth. Research mapping was conducted to analyze the concept of risk tolerance. This concept was related to people's risk aversion effects when making a decision under risk and the role of financial knowledge on changes in financial income. Understanding and managing risks and investments are complicated, in particular for corporate managers, who are always demanded to maintain their corporate growth. Substantial financial knowledge is extremely needed to identify and take accurate information for corporate financial decision-making. By reviewing several literature, this study hypothesized that financial knowledge of corporate managers would be meaningless without manager's courage to bear risks for taking favorable business opportunities. Therefore, the level of risk aversion from corporate managers will determine corporate action, which is a reflection of corporate-level investment behavior leading to attain corporate success or failure for achieving the company's expected growth rate.

Keywords: financial knowledge, financial risk attitude, corporate growth, risk tolerance

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1503 Analytical Description of Disordered Structures in Continuum Models of Pattern Formation

Authors: Gyula I. Tóth, Shaho Abdalla

Abstract:

Even though numerical simulations indeed have a significant precursory/supportive role in exploring the disordered phase displaying no long-range order in pattern formation models, studying the stability properties of this phase and determining the order of the ordered-disordered phase transition in these models necessitate an analytical description of the disordered phase. First, we will present the results of a comprehensive statistical analysis of a large number (1,000-10,000) of numerical simulations in the Swift-Hohenberg model, where the bulk disordered (or amorphous) phase is stable. We will show that the average free energy density (over configurations) converges, while the variance of the energy density vanishes with increasing system size in numerical simulations, which suggest that the disordered phase is a thermodynamic phase (i.e., its properties are independent of the configuration in the macroscopic limit). Furthermore, the structural analysis of this phase in the Fourier space suggests that the phase can be modeled by a colored isotropic Gaussian noise, where any instant of the noise describes a possible configuration. Based on these results, we developed the general mathematical framework of finding a pool of solutions to partial differential equations in the sense of continuous probability measure, which we will present briefly. Applying the general idea to the Swift-Hohenberg model we show, that the amorphous phase can be found, and its properties can be determined analytically. As the general mathematical framework is not restricted to continuum theories, we hope that the proposed methodology will open a new chapter in studying disordered phases.

Keywords: fundamental theory, mathematical physics, continuum models, analytical description

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1502 M. J. Rodríguez, F. M. Sánchez, B. Velardo, P. Calvo, M. J. Serradilla, J. Delgado, J. M. López

Authors: Q. Rzina, M. Lahrouni, S. Rida, N. Saadaoui, Y. Almossaid, K. Oufdou, K. Fares

Abstract:

Many organic solid wastes are produced in the world. Poultry manure (PM), municipal organic wastes (MOW) and sugar beet lime sludge (LS) are produced in large quantities in Morocco. The co-composting of these organic wastes was investigated. The recycling and the valorization of such wastes is environmentally and economically beneficial especially for PM which is known source of bacterial pathogens. The aerobic biodegradation process was carried out by using three windrows of variable compositions: C1 prepared without LS (only MOW were composted with PM), C2 prepared from MOW plus PM and10% LS; and the last one C3 from MOW plus PM and 20% LS. The main process physico-chemical parameters (temperature, pH, humidity and C/N) and microbiological populations (mesophilic and thermophilic flora, total coliform, fecal coliform, Streptococci, Staphylococcus aureus and mesophilic fungi) were monitored over three months to ascertain the compost maturity and to ensure the compost hygienic aspect. The final products were characterized by their relatively high organic matter content, and low C/N ratio of 10.6-10.9. The organic matter degradation was reached approximately 59% for C2 and C3. In addition, the monitoring of the microbial population showed that the produced composts are mature and hygienic. The agronomic valorization of the final composts was tested on radish plant with tree level of composts and poultry manure without composting. The primary results of field trial showed a growth of radish plant biomass and root development without any phytotoxicity detected which reflects the quality of the composts produced. As for poultry manure it allowed to have a better results than other composts because of its readily available nitrogen.

Keywords: compost, municipal organic wastes, poultry manure, radish crop, sugar beet lime sludge

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1501 Near Optimal Closed-Loop Guidance Gains Determination for Vector Guidance Law, from Impact Angle Errors and Miss Distance Considerations

Authors: Karthikeyan Kalirajan, Ashok Joshi

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An optimization problem is to setup to maximize the terminal kinetic energy of a maneuverable reentry vehicle (MaRV). The target location, the impact angle is given as constraints. The MaRV uses an explicit guidance law called Vector guidance. This law has two gains which are taken as decision variables. The problem is to find the optimal value of these gains which will result in minimum miss distance and impact angle error. Using a simple 3DOF non-rotating flat earth model and Lockheed martin HP-MARV as the reentry vehicle, the nature of solutions of the optimization problem is studied. This is achieved by carrying out a parametric study for a range of closed loop gain values and the corresponding impact angle error and the miss distance values are generated. The results show that there are well defined lower and upper bounds on the gains that result in near optimal terminal guidance solution. It is found from this study, that there exist common permissible regions (values of gains) where all constraints are met. Moreover, the permissible region lies between flat regions and hence the optimization algorithm has to be chosen carefully. It is also found that, only one of the gain values is independent and that the other dependent gain value is related through a simple straight-line expression. Moreover, to reduce the computational burden of finding the optimal value of two gains, a guidance law called Diveline guidance is discussed, which uses single gain. The derivation of the Diveline guidance law from Vector guidance law is discussed in this paper.

Keywords: Marv guidance, reentry trajectory, trajectory optimization, guidance gain selection

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1500 Online vs. in vivo Workshops in a Masters’ Degree Course in Mental Health Nursing: Students’ Views and Opinions

Authors: Evmorfia Koukia, Polyxeni Mangoulia

Abstract:

Workshops tend to be a vivid and productive way as an in vivo teaching method. Due to the pandemic, COVID-19 university courses were conducted through the internet. Method It was tried for the first time to integrate online art therapy workshops in a core course named “Special Themes of Mental Health Nursing” in a MSc Program in Mental Health. The duration of the course is 3-hours per week for 11 weeks in a single semester. The course has a main instructor, a professor of psychiatric nursing experienced in arts therapies workshops and visiting art therapists. All art therapists were given a certain topic to cover. Students were encouraged to keep a logbook that was evaluated at the end of the semester and was submitted as a part of the examination process of the course. An interview of 10 minutes was conducted with each student at the end of the course from an independent investigator (an assistant professor) Participants The students (sample) of the program were: nurses, psychologists, and social workers Results: All students who participated in the courses found that the learning process was vivid, encouraging participation and self-motivation, and there were no main differences from in vivo learning. The students identified their personal needs, and they felt a personal connection with the learning experience. The result of the personalized learning was that students discovered their strengths and weaknesses and developed skills like critical thinking. All students admitted that the workshops were the optimal way for them to comprehend the courses’ content, their capability to become therapists, as well as their obstacles and weaknesses while working with patients in mental health. Conclusion: There were no important differences between the views of students in online and in vivo teaching method of the workshops. The result has shown that workshops in mental health can contribute equally in the learning experience.

Keywords: mental health, workshops, students, nursing

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