Search results for: shake table tests

Authors: R. N. Khare, J. P. Sahu, Rajesh Kumar Tamrakar

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Tests were conducted to determine the property of soil with variation of H2SO4 content for soils under different stage. The soils had varying amounts of plasticity’s ranging from low to high plasticity. The unsaturated soil behavior was investigated for different conditions, covering a range of compactive efforts and water contents. The soil characteristic curves were more sensitive to changes in compaction effort than changes in compaction water content. In this research paper two types of water (Ground water Ph =7.9, Turbidity= 13 ppm; Cl =2.1mg/l and surface water Ph =8.65; Turbidity=18.5; Cl=1mg/l) were selected of Bhilai Nagar, State-Chhattisgarh, India which is mixed with a certain type of soil. Results shows that by the presence of ground water day by day the particles are becoming coarser in 7 days thereafter its size reduces; on the other hand by the presence of surface water the courser particles are disintegrating, finer particles are accumulating and also the dry density is reduces. Plasticity soils retained the smallest water content and the highest plasticity soils retained the highest water content at a specified suction. In addition, soil characteristic for soils to be compacted in the laboratory and in the field are still under process for analyzing the bearing capacity. The bearing capacity was reduced 2 to 3 times in the presence of H2SO4.

Keywords: soil compaction, H2SO4, soil water, water conditions

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Authors: Ya-Chi Yu, Pei-Syuan Ruan, Shao-Wen Chen, Yu-Hsien Chang, Jin-Der Lee, Jong-Rong Wang, Chunkuan Shih

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This study analyzed the transient signals of central region void fraction of air-water two-phase flow in a 3x3 rod bundle. Experimental tests were carried out utilizing a vertical rod bundle test section along with a set of air-water supply/flow control system, and the transient signals of the central region void fraction were collected through the electrical conductivity sensors as well as visualized via high speed photography. By converting the electric signals, transient void fraction can be obtained through the voltage ratios. With a fixed superficial water velocity (J_f=0.094 m/s), two different superficial air velocities (J_g=0.094 m/s and 0.236 m/s) were tested and presented, which were corresponding to the flow conditions of bubbly flows and cap/slug flows, respectively. The time averaged central region void fraction was obtained as 0.109-0.122 with 0.028 standard deviation for the selected bubbly flow and 0.188-0.221with 0.101 standard deviation for the selected cap/slug flow, respectively. Through Fast Fourier Transform (FFT) analysis, no clear frequency peak was found in bubbly flow, while two dominant frequencies were identified around 1.6 Hz and 2.5 Hz in the present cap/slug flow.

Keywords: central region, rod bundles, transient void fraction, two-phase flow

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Authors: Luis E. Zapata, Sergio Ruiz, María F. Mantilla, Jhon A. Villamizar

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Sand as fine aggregate for concrete production needs a feasible substitute due to several environmental issues. In this work, a study of the behavior of self-compacting concrete mixtures under replacement of sand by iron slag from 0.0% to 50.0% of weight and variations of water/cementitious material ratio between 0.3 and 0.5 is presented. Control fresh state tests of Slump flow, T500, J-ring and L-box were determined. In the hardened state, compressive strength was determined and optimization from response surface analysis was performed. The study of the variables in the hardened state was developed based on inferential statistical analyses using central composite design methodology and posterior analyses of variance (ANOVA). An increase in the compressive strength up to 50% higher than control mixtures at 7, 14, and 28 days of maturity was the most relevant result regarding the presence of iron slag as replacement of natural sand. Considering the obtained result, it is possible to infer that iron slag is an acceptable alternative replacement material of the natural fine aggregate to be used in structural concrete.

Keywords: ANOVA, iron slag, response surface analysis, self-compacting concrete

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Authors: Sylvain Caillol, Ghislain David

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Phenolic resins are industrially used in a wide range of applications from commodity and construction materials to high-technology aerospace industry. They are mainly produced from the reaction between phenolic compounds and formaldehyde. Nevertheless, formaldehyde is a highly volatile and hazardous compound, classified as a Carcinogenic, Mutagenic and Reprotoxic chemical (CMR). Vanillin is a bio-based and non-toxic aromatic aldehyde compound obtained from the abundant lignin resources. Also, its aromaticity is very interesting for the synthesis of phenolic resins with high thermal stability. However, because of the relatively low reactivity of its aldehyde function toward phenolic compounds, it has never been used to synthesize phenolic resins. We developed innovative functionalization reactions and designed new bio-based aromatic aldehyde compounds from vanillin. Those innovative compounds present improved reactivity toward phenolic compounds compared to vanillin. Moreover, they have target structures to synthesize highly cross-linked phenolic resins with high aromatic densities. We have obtained phenolic resins from substituted vanillin, thus without the use of any aldehyde compound classified as CMR. The analytical tests of the cured resins confirmed that those bio-based resins exhibit high levels of performance with high thermal stability and high rigidity properties

Keywords: phenolic resins, formaldehyde-free, vanillin, bio-based, non-toxic

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Authors: Harald Haas, Andrea Plaschke

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Many of the contemporary major conflicts on this earth could not be solved so far, they either are perpetuated, or they are reflated again and again. Efforts of purely political conflict management or -resolution aim merely at the symptoms of conflict, not its roots. These roots are, in almost every case, also psychological ones. Thus, this contribution aims to shed light on the roots of one of the best known and longest-lasting conflicts: the Palestinian-Israeli one. Methodologies used were the compilation of existing scientific resources, field research in Palestine and Israel, as well as tests conducted with the Adult Attachment Projective in Palestine and Israel. Findings show that the majority of Palestinian, as well as Israeli test participants, show a disorganised attachment pattern which, in connection with the assumption of collective traumatization, seem to be a major obstacle to a lasting and peaceful conflict-resolution between these two peoples. There appears to be no short-term solution for this conflict, especially not within the range of usual Western legislative periods. Both sides ought to be provided with a kind of 'safe haven' over a long period of time, accompanied by a framework of various arrangements of coping with trauma, building lasting and secure relationships, as well as raising and educating present and future generations of Palestinians and Israelis for peace and co-operation with each other.

Keywords: conflict-management, trauma, political psychology, attachment theory

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Authors: S. Rostampour Yasouri, M. Ghane

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Leptospirosis is one the most important common diseases between human and live stock occurred by different species of Leptospira. This disease has been construed as the native in the northern provinces of Iran and risk of the infection with pathogenic is high. One hundred fifteen samples of water (67), soil (36) and feces of rodents (12) were collected from the rice fields of the suburbs of Tonekabon Township situated in northern part of Iran in 2012. The samples, after passage from membranous filters, were cultured in the liquid and solid EMJH medium and incubated at 30°C for 1 month. Leptospira spp. were isolated using culture technique, and the plates were studied from viewpoint of colony formation, microscopic observations and then identified by phenotyping tests. Finally, the identification of Leptospira genus was verified by PCR technique and 16S rRNA gene sequencing. Of 115 samples totally, 55 samples (47.82%) became positive by use of the culture technique which the positive cases included 47 water samples (70.14%) and 8 soil samples (22.22%), while the isolation was not accomplished from the sample of the rodents feces. Overall, according to these data, Leptospira spp. exists with high frequency in North Iran. Hence, based on foregoing evidence environments in the north of Iran are vehicles of Leptospira spp.

Keywords: EMJH Medium, Leptospira, Northern of Iran, rice fields

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Authors: Sepase K. Ivande

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Morality and frugality are two of the strongest motivations for pro-environmental behavior. However, formulating interventions based on these motivations requires knowledge of who is likely to be motivated by morality and who by frugality. This study investigated which personality traits make someone predisposed to morality motivation and which to frugality motivation for pro-environmental behavior. Results from a series of multiple regression analyses indicated that openness and agreeableness had a positive association with morality motivation, while conscientiousness had a positive association with frugality motivation. The link of agreeableness to morality motivation was stronger when the individuals were also higher on openness. Furthermore, a pair of Wilcoxon signed-rank tests revealed that individuals high on openness and agreeableness but low on conscientiousness scored higher on morality than frugality motivation. On the other hand, individuals low on openness and agreeableness but high on conscientiousness scored higher on frugality than morality motivation. The results of this study could inform the formulation of personalized interventions based on people’s personal predisposition to morality and frugality motivation for pro-environmental behavior, which could be more effective in getting them to be pro-environmental.

Keywords: agreeableness, conscientiousness, frugality, higher order motivations, morality, openness to experience, personality traits, pro-environmental behavior

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Authors: B. Nečasová, P. Liška, J. Šlanhof

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Verification of vented wooden façade system with bonded joints is presented in this paper. The potential of bonded joints is studied and described in more detail. The paper presents the results of an experimental and theoretical research about the effects of freeze cycling on the bonded joint. For the purpose of tests spruce timber profiles were chosen for the load bearing substructure. Planks from wooden plastic composite and Siberian larch are representing facade cladding. Two types of industrial polyurethane adhesives intended for structural bonding were selected. The article is focused on the preparation as well as on the subsequent curing and conditioning of test samples. All test samples were subjected to 15 cycles that represents sudden temperature changes, i.e. immersion in a water bath at (293.15 ± 3) K for 6 hours and subsequent freezing to (253.15 ± 2) K for 18 hours. Furthermore, the retention of bond strength between substructure and cladding was tested and strength in shear was determined under tensile stress. Research data indicate that little, if any, damage to the bond results from freezing cycles. Additionally, the suitability of selected group of adhesives in combination with timber substructure was confirmed.

Keywords: adhesive system, bonded joints, wooden lightweight façade, timber substructure

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Authors: Sally Shepherd, Craig Murphy

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Introduction: The uterus or cervix are unusual locations as metastatic sites for cancers. It is further unusual for it to be a site of metastasis, whilst the primary malignancy remains occult. Case Report: A 63-year-old female with three months of altered bowel habits underwent a CT scan of the abdomen and pelvis, revealing a bulky uterus and left ovary, nonspecific colonic thickening, and diffuse peritoneal changes. She underwent colposcopy, which revealed a large endocervical polyp that was excised, revealing strongly hormone-positive metastatic invasive lobular breast cancer. She subsequently underwent a PET scan, which showed moderately diffuse activity in the cervix and left adnexa. Breast examination was unremarkable, and screening mammography, ultrasound, and MRI of the breast did not identify any lesions. Her blood tests revealed a Ca 15-3 of 934, CA-125 of 220, and CEA of 27. She was commenced on letrozole and ribociclib with an improvement in her symptoms. Conclusion: It is rare for occult breast cancer to be established and diagnosed by pelvic imaging and biopsy. Suspicion of uterine or cervical metastasis should be heightened in patients with an active or past history of breast cancer.

Keywords: occult breast cancer, cervical metastasis, invasive lobular carcinoma, metastasis

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Authors: Peter Sabev, Katalina Grigorova

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Test automation allows performing difficult and time consuming manual software testing tasks efficiently, quickly and repeatedly. However, development and maintenance of automated tests is expensive, so it needs a proper prioritization what to automate first. This paper describes a simple yet efficient approach for such prioritization of test cases based on the effort needed for both manual execution and software test automation. The suggested approach is very flexible because it allows working with a variety of assessment methods, and adding or removing new candidates at any time. The theoretical ideas presented in this article have been successfully applied in real world situations in several software companies by the authors and their colleagues including testing of real estate websites, cryptographic and authentication solutions, OSGi-based middleware framework that has been applied in various systems for smart homes, connected cars, production plants, sensors, home appliances, car head units and engine control units (ECU), vending machines, medical devices, industry equipment and other devices that either contain or are connected to an embedded service gateway.

Keywords: automated testing, manual testing, test automation, software testing, test prioritization

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Authors: Sifeddine Abderrahmani, Sonia Bouafia

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The finite element method is the most practical tool for the analysis of structures, whatever the geometrical shape and behavior. It is extensively used in many high-tech industries, such as civil or military engineering, for the modeling of bridges, motor bodies, fuselages, and airplane wings. Additionally, experience demonstrates that engineers like modeling their structures using the most basic finite elements. Numerous models of finite elements may be utilized in the numerical analysis depending on the interpolation field that is selected, and it is generally known that convergence to the proper value will occur considerably more quickly with a good displacement pattern than with a poor pattern, saving computation time. The method for creating finite elements using the strain approach (S.B.A.) is presented in this presentation. When the results are compared with those provided by equivalent displacement-based elements, having the same total number of degrees of freedom, an excellent convergence can be obtained through some application and validation tests using recently developed membrane elements, plate bending elements, and flat shell elements. The effectiveness and performance of the strain-based finite elements in modeling structures are proven by the findings for deflections and stresses.

Keywords: finite elements, plate bending, strain approach, displacement formulation, shell element

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Authors: Jun-ya Nagase

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There are many pipes such as a water pipe and a gas pipe in a chemical plant and house. It is possible to prevent accidents by these inspections. However, many pipes are very narrow and it is difficult for people to inspect directly. Therefore, development of a robot that can move in narrow pipe is necessary. A wheel movement type robot, a snake-like robot and a multi-leg robot are all described in the relevant literature as pipe inspection robots that are currently studied. Among them, the tracked crawler robot can travel by traversing uneven ground flexibly with a crawler belt attached firmly to the ground surface. Although conventional crawler robots have high efficiency and/or high ground-covering ability, they require a comparatively large space to move. In this study, a cylindrical crawler robot based on worm-rack mechanism, which does not need large space to move and which has high ground-covering ability, is proposed. Experiments have demonstrated smooth operation and a forward movement of the robot by application of voltage to the motor. In addition, performance tests show that it can propel itself in confined spaces. This paper reports the structure, drive mechanism, prototype, and experimental evaluation.

Keywords: tracked-crawler, pipe inspection robot, worm-rack mechanism, amoeba locomotion

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Authors: Samaneh Abolli, Mahdi Ahmadi Nasab, Kamyar Yaghmaeian, Mahmood Alimohammadi

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The quality of drinking water, in addition to the presence of physicochemical parameters, depends on the type and geographical location of water sources. In this study, groundwater quality was investigated by sampling total dissolved solids (TDS), electrical conductivity (EC), total hardness (TH), Cl, Ca²⁺, and Mg²⁺ parameters in 13 sites, and 40 water samples were sent to the laboratory. Electrometric, titration, and spectrophotometer methods were used. In the next step, the water quality index (WQI) was used to investigate the impact and weight of each parameter in the groundwater. The results showed that only the mean of magnesium ion (40.88 mg/l) was lower than the guidelines of World Health Organization (WHO). Interpreting the WQI based on the WHO guidelines showed that the statuses of 21, 11, and 7 samples were very poor, poor, and average quality, respectively, and one sample had excellent quality. Among the studied parameters, the means of EC (2,087.49 mS/cm) and Cl (1,015.87 mg/l) exceeded the global and national limits. Classifying water quality of TH was very hard (87.5%), hard (7.5%), and moderate (5%), respectively. Based on the geographical distribution, the drinking water index in sites 4 and 11 did not have acceptable quality. Chloride ion was identified as the responsible pollutant and the most important ion for raising the index. The outputs of statistical tests and Spearman correlation had significant and direct correlation (p < 0.05, r > 0.7) between TDS, EC, and chloride, EC and chloride, as well as TH, Ca²⁺, and Mg²⁺.

Keywords: water quality index, groundwater, chloride, GIS, Garmsar

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Authors: Carolina Gheller Miguens

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Feeding is, and should be, pleasurable for living beings so they desire to nourish themselves while preserving the continuity of the species. Social rites usually revolve around the table and are closely linked to the cultural traditions of each region and social group. Since the beginning, food has been closely linked with the products each region provides, and, also, related to the respective seasons of production. With the globalization and facilities of modern life we are able to find an ever increasing variety of products at any time of the year on supermarket shelves. These lifestyle changes end up directly influencing food traditions. With the era of uncontrolled obesity caused by the dazzle with the large and varied supply of low-priced to ultra-processed industrial products now in the past, today we are living a time when people are putting aside the pleasure of eating to exclusively eat food dictated by the media as healthy. Recently the medicalization of food in our society has become so present in daily life that almost without realizing we make food choices conditioned to the studies of the properties of these foods. The fact that people are more attentive to their health is interesting. However, when this care becomes an obsessive disorder, which imposes itself on the pleasure of eating and extinguishes traditional customs, it becomes dangerous for our recognition as citizens belonging to a culture and society. This new way of living generates a rupture with the social environment of origin, possibly exposing old traditions to oblivion after two or three generations. Based on these facts, the presented study analyzes these social transformations that occur in our society that triggered the current medicalization of food. In order to clarify what is actually a healthy diet, this research proposes a critical analysis on the subject aiming to understand nutritional rationality and relate how it acts in the medicalization of food. A wide bibliographic review on the subject was carried out followed by an exploratory research in online (especially social) media, a relevant source in this context due to the perceived influence of such media in contemporary eating habits. Finally, this data was crossed, critically analyzing the current situation of the concept of healthy eating and medicalization of food. Throughout this research, it was noticed that people are increasingly seeking information about the nutritional properties of food, but instead of seeking the benefits of products that traditionally eat in their social environment, they incorporate external elements that often bring benefits similar to the food already consumed. This is because the access to information is directed by the media and exalts the exotic, since this arouses more interest of the population in general. Efforts must be made to clarify that traditional products are also healthy foods, rich in history, memory and tradition and cannot be replaced by a standardized diet little concerned with the construction of taste and pleasure, having a relationship with food as if it were a Medicinal product.

Keywords: food traditions, food transformations, healthy eating, medicalization of food

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Authors: Christina Jery, R. K. Anjana, D. N. Arnepalli, R. Sobha

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Modern landfills employ a composite liner consisting of a geomembrane overlying a compacted clay liner (CCL) or a geosynthetic clay liner (GCL) as a barrier system. The primary function of a barrier system is to control the contaminant transport from the leachate (dissolved phase) and landfill gas (vapour phase) out of the landfill thereby minimizing the environmental impact. This study is undertaken to investigate the diffusive migration of VOCs through composite liners. VOCs are known hazardous air pollutants were often existing in both the vapour phase and dissolved phase. These compounds are known to diffuse readily through the polymeric geomembranes. The objective of the research is to develop a comprehensive data set of diffusive parameters involved in the diffusion of VOCs in the composite liner (1.5 mm HDPE geomembrane overlying a 30mm compacted clay layer). For this purpose, the study aims to develop a new experimental setup for determining the diffusion characteristics. The key parameters of diffusion (partitioning, diffusion and permeation coefficients) are examined. The diffusion tests are carried out both in aqueous and vapor phase. Finally, an attempt is also made to study the effect of low temperature on the diffusion characteristics.

Keywords: diffusion, sorption, organic compounds, composite liners, geomembrane

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Authors: I. Parkova, A. Vališevskis, A. Viļumsone

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Nocturnal enuresis or bed-wetting is intermittent incontinence during sleep of children after age 5 that may precipitate wide range of behavioural and developmental problems. One of the non-pharmacological treatment methods is the use of a bed-wetting alarm system. In order to improve comfort conditions of nocturnal enuresis alarm system, modular moisture sensor should be replaced by a textile sensor. In this study behaviour and moisture detection speed of woven and sewn sensors were compared by analysing change in electrical resistance after solution (salt water) was dripped on sensor samples. Material of samples has different structure and yarn location, which affects solution detection rate. Sensor system circuit was designed and two sensor tests were performed: system activation test and false alarm test to determine the sensitivity of the system and activation threshold. Sewn sensor had better result in system’s activation test – faster reaction, but woven sensor had better result in system’s false alarm test – it was less sensitive to perspiration simulation. After experiments it was found that the optimum switching threshold is 3V in case of 5V input voltage, which provides protection against false alarms, for example – during intensive sweating.

Keywords: conductive yarns, moisture textile sensor, industry, material

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Authors: Nabaa M. Abdul Rahim, Mohammed A.Kadhim, Fadhil K. Fuliful

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A biocompatible layer is prepared from calcium phosphate, which plays a role in building damaged bones and is used in many applications. In this research, calcium phosphate is coated on stainless steel substrates (SS 316) by using the flame coating. FE-SEM images show that the behavior of the sample surfaces varies with distance, at 3cm, appeared with nanostructures of bumps shaped of diameter about 317 nm. The contents of the elements are analyzed by energy-dispersive X-ray spectroscopy (EDX). The chemical elements C, Ca, Fe, Ni, Cr, Mn and O corresponding to calcium phosphate and the alloy are revealed by EDX analysis of the coating layer. XRD patterns for the calcium phosphate layers indicate the formation of the Hap layer on the deposited layers. The samples are immersed in a solution of simulated body fluids (SBF) for 21 days to examine the biocompatibility, as the tests show that the calcium phosphate ratio of 1.65 is the appropriate and biocompatible ratio in the human body. The assays show antibacterial activity using the diffusion disk procedure. On the surface of the agar, observed infested E.coli bacteria and incubated for 24 hours at 37°C. Bacteria grow on the entire agar rather than in some areas around some samples at a distance of 3 cm from the flame hole.

Keywords: biomaterial, flame coating, antibacterial activity, stainless steel

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Authors: Tarek Duzan, Walid Eddib

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The marine shallow carbonate reservoir (G- Eocene) is one of the biggest mature water drive reservoir of Waha Oil Company. The cumulative oil produced up to date is about to eighty percent of the booked original oil in place at ninety five percent of Water cut. However, the company believes that there is a good amount of remaining oil left need to be recovered. Many laboratory studies have been conducted to see the possibility drain the commercial oil left behind using two types of gases, namely, carbone dioxide and enriched hydrocarbon gas injection. The conclusions of those cases were inconclusive Technically and Economically. Therefore, the company has decided to verify another Tertiary Recovery (EOR) technique that may be applied to the interested reservoir. A global screening criteria and quick Laboratory chemical tests have been conducted by using many types of chemical injection into real rock samples. The outcomes were unique economically and provide a significant increase in the commercial oil left. Finally, the company has started conducting a sector pilot plan before proceeding with a full plan. There are many wellbores available to use in a potential field Enhanced Oil Recovery.

Keywords: chemical lab. test, ASP, rock types, oil samples, and global screening criteria

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Authors: Elisha Kyirem

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Undoubtedly, climate change is a major global challenge that could threaten the very foundation upon which life on earth is anchored, with its impacts on human mobility attracting the attention of policy makers and researchers. There is an increasing body of literature and case studies suggesting that migration could be a way through which the vulnerable move away from areas exposed to climate extreme events to improve their lives and that of their families. This presents migration as a way through which people voluntarily move to seek opportunities that could help reduce their exposure and avoid danger from climate events. Thus, migration is seen as a proactive adaptation strategy aimed at building resilience and improving livelihoods to enable people to adapt to future changing events. However, there has not been any mathematical equation linking migration and climate change adaptation. Drawing from literature in development studies, this paper develops an equation that seeks to link the relationship between migration and climate change adaptation. The mathematical equation establishes the linkages between migration, resilience, poverty reduction and vulnerability, and these the paper maintains, are the key variables for conceptualizing the migration-climate change adaptation nexus. The paper then tests the validity of the equation using the sustainable livelihood framework and publicly available data on migration and tourism in Ghana.

Keywords: migration, adaptation, climate change, adaptation, poverty reduction

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Authors: Abbas S. Al-Ameeri Rawaa H. Issa

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The internal sulfate attack is considered as a very important problem of concrete manufacture in Iraq and Middle East countries. Sulfate drastically influences the properties of concrete. This experimental study is aimed at investigating the effect of internal sulfates on fresh and some of the hardened properties of self compacting concrete (SCC) made from locally available materials. Tests were conducted on five mixes, with five SO3 levels (3.9, 5, 6, 7 and 8) (% by wt. of cement). The last four SO3 levels are outside the limits of the Iraqi specifications (IQS NO.45/1984). The results indicated that sulfate passively influenced the fresh properties such as decreased workability, and effect on hardened properties of the self compacting concrete. Also, the result indicated the optimum SO3 content which gives maximum strength and little tendency to expanding, which showed up at a content equal to 5% (by wt of cement), is more than acceptable limits of Iraqi specifications. Further increase in sulfates content in concrete after this optimum value showed a considerable reduction in mechanical properties of self-compacting concrete, and increment in expansion of concrete. The percentages of reduction in compressive strength, splitting tensile strength, flexural strength, static modulus of elasticity and ultrasonic pulse velocity at their later age were ranged between 10.89-36.14%, 12.90-33.33%, 7.98-36.35%, 16.36 -38.37% and 1.03-10.88% respectively.

Keywords: self-compacting concrete, sulfate attack, internal sulfate attack, fresh properties, harden properties, optimum SO3 content

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Authors: Hayyan I Al Taweil

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Background: The most common of bacterium in kitchen sponges and cutting surfaces which can play a task within the cross-contamination of foods, fomites and hands by foodborne pathogens. Aims and Objectives: This study investigated the incidence of bacterium in kitchen Sponge, and cutting surfaces. Material and methods: a complete of twenty four kitchen Sponges were collected from home kitchens and therefore the numbers of mesotrophic microorganism, coliform microorganism, E. coli, Salmonella, genus {pseudomonas|bacteria genus} and staphylococci in every kitchen Sponges were determined. Microbiological tests of all sponges for total mesophilic aerobic microorganism, S. aureus, Pseudomonas, Salmonella spp., and E. coli were performed on days 3, 7, and 14 by sampling. The sponges involved in daily use in kitchens countenosely with the dishwasher detergent a minimum of doubly daily Results: Results from the overall mesophilic aerobic microorganism, indicate a major increase within the variety of log CFU/ml. the amount of E. coli was reduced, Salmonella spp. was stabled, S. aureus was enhanced from the sponges throughout fourteen days. Genus Pseudomonas was enhanced and was the dominant micro flora within the sponges throughout fourteen days.

Keywords: Kitchen Sponges, Microbiological Contamination, Disinfection; cutting surface; , Cross-Contamination

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Authors: S. N. Deepa, A. D. Srinivasan, K. T. Veeramanju, R. Sandeep Kumar, Ashwini Mathapati

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Power transformer is a vital element in a power system as it continuously regulates power flow, maintaining good voltage regulation. The working of transformer much depends on the oil insulation, the oil insulation also decides the aging of transformer and hence its reliability. The mineral oil based liquid insulation is globally accepted for power transformer insulation; however it is potentially hazardous due to its non-biodegradability. In this work efficient alternative biodegradable insulating fluid is presented as a replacement to conventional mineral oil. Dielectric tests are performed as distinct alternating fluid to evaluate the suitability for transformer insulation. The selection of the distinct natural esters for an insulation system is carried out by the laboratory investigation of Breakdown voltage, Oxidation stability, Dissipation factor, Permittivity, Viscosity, Flash and Fire point. It is proposed to study and characterize the properties of natural esters to be used in power transformer. Therefore for the investigation of the dielectric behavior rice bran oil, sesame oil, and sunflower oil are considered for the study. The investigated results have been compared with the mineral oil to validate the dielectric behavior of natural esters.

Keywords: alternative insulating fluid, dielectric properties, natural esters, power transformers

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Authors: Lee Yan Nian

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Safety investigation is different from an administrative investigation in that the former is conducted by an independent agency and the purpose of such investigation is to prevent accidents in the future and not to apportion blame or determine liability. Before October 2018, Taiwan railway occurrences were investigated by local supervisory authority. Characteristics of this kind of investigation are that enforcement actions, such as administrative penalty, are usually imposed on those persons or units involved in occurrence. On October 21, 2018, due to a Taiwan Railway accident, which caused 18 fatalities and injured another 267, establishing an agency to independently investigate this catastrophic railway accident was quickly decided. The Taiwan Transportation Safety Board (TTSB) was then established on August 1, 2019 to take charge of investigating major aviation, marine, railway and highway occurrences. The objective of this study is to assess the effectiveness of safety investigations conducted by the TTSB. In this study, the major railway occurrence investigation reports published by the TTSB are used for modeling and analysis. According to the classification of railway occurrences investigated by the TTSB, accident types of Taiwan railway occurrences can be categorized into: derailment, fire, Signal Passed at Danger and others. A Causal Factor Analysis System (CFAS) developed by the TTSB is used to identify the influencing causal factors and their causal relationships in the investigation reports. All terminologies used in the CFAS are equivalent to the Human Factors Analysis and Classification System (HFACS) terminologies, except for “Technical Events” which was added to classify causal factors resulting from mechanical failure. Accordingly, the Bayesian network structure of each occurrence category is established based on the identified causal factors in the CFAS. In the Bayesian networks, the prior probabilities of identified causal factors are obtained from the number of times in the investigation reports. Conditional Probability Table of each parent node is determined from domain experts’ experience and judgement. The resulting networks are quantitatively assessed under different scenarios to evaluate their forward predictions and backward diagnostic capabilities. Finally, the established Bayesian network of derailment is assessed using investigation reports of the same accident which was investigated by the TTSB and the local supervisory authority respectively. Based on the assessment results, findings of the administrative investigation is more closely tied to errors of front line personnel than to organizational related factors. Safety investigation can identify not only unsafe acts of individual but also in-depth causal factors of organizational influences. The results show that the proposed methodology can identify differences between safety investigation and administrative investigation. Therefore, effective intervention strategies in associated areas can be better addressed for safety improvement and future accident prevention through safety investigation.

Keywords: administrative investigation, bayesian network, causal factor analysis system, safety investigation

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Authors: K. D. R. Jagath-Kumara, D. D. Dias

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The sea waves carry thousands of GWs of power globally. Although there are a number of different approaches to harness offshore energy, they are likely to be expensive, practically challenging and vulnerable to storms. Therefore, this paper considers using the near shore waves for generating mechanical and electrical power. It introduces two new approaches, the wave manipulation and using a variable duct turbine, for intercepting very wide wave fronts and coping with the fluctuations of the wave height and the sea level, respectively. The first approach effectively allows capturing much more energy yet with a much narrower turbine rotor. The second approach allows using a rotor with a smaller radius but captures energy of higher wave fronts at higher sea levels yet preventing it from totally submerging. To illustrate the effectiveness of the approach, the paper contains a description and the simulation results of a scale model of a wave manipulator. Then, it includes the results of testing a physical model of the manipulator and a single duct, axial flow turbine, in a wave flume in the laboratory. The paper also includes comparisons of theoretical predictions, simulation results and wave flume tests with respect to the incident energy, loss in wave manipulation, minimal loss, brake torque and the angular velocity.

Keywords: near-shore sea waves, renewable energy, wave energy conversion, wave manipulation

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Authors: Simone Dell'Agnello

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There are laser retroreflectors on the Moon and no laser retroreflectors on Mars. Here we describe the design, construction, qualification and imminent deployment of next-generation, optimized laser retroreflectors on the Moon and on Mars (where they will be the first ones). These instruments are positioned by time-of-flight measurements of short laser pulses, the so-called 'laser ranging' technique. Data analysis is carried out with PEP, the Planetary Ephemeris Program of CfA (Center for Astrophysics). Since 1969 Lunar Laser Ranging (LLR) to Apollo/Lunokhod laser retro-reflector (CCR) arrays supplied accurate tests of General Relativity (GR) and new gravitational physics: possible changes of the gravitational constant Gdot/G, weak and strong equivalence principle, gravitational self-energy (Parametrized Post Newtonian parameter beta), geodetic precession, inverse-square force-law; it can also constraint gravitomagnetism. Some of these measurements also allowed for testing extensions of GR, including spacetime torsion, non-minimally coupled gravity. LLR has also provides significant information on the composition of the deep interior of the Moon. In fact, LLR first provided evidence of the existence of a fluid component of the deep lunar interior. In 1969 CCR arrays contributed a negligible fraction of the LLR error budget. Since laser station range accuracy improved by more than a factor 100, now, because of lunar librations, current array dominate the error due to their multi-CCR geometry. We developed a next-generation, single, large CCR, MoonLIGHT (Moon Laser Instrumentation for General relativity high-accuracy test) unaffected by librations that supports an improvement of the space segment of the LLR accuracy up to a factor 100. INFN also developed INRRI (INstrument for landing-Roving laser Retro-reflector Investigations), a microreflector to be laser-ranged by orbiters. Their performance is characterized at the SCF_Lab (Satellite/lunar laser ranging Characterization Facilities Lab, INFN-LNF, Frascati, Italy) for their deployment on the lunar surface or the cislunar space. They will be used to accurately position landers, rovers, hoppers, orbiters of Google Lunar X Prize and space agency missions, thanks to LLR observations from station of the International Laser Ranging Service in the USA, in France and in Italy. INRRI was launched in 2016 with the ESA mission ExoMars (Exobiology on Mars) EDM (Entry, descent and landing Demonstration Module), deployed on the Schiaparelli lander and is proposed for the ExoMars 2020 Rover. Based on an agreement between NASA and ASI (Agenzia Spaziale Italiana), another microreflector, LaRRI (Laser Retro-Reflector for InSight), was delivered to JPL (Jet Propulsion Laboratory) and integrated on NASA’s InSight Mars Lander in August 2017 (launch scheduled in May 2018). Another microreflector, LaRA (Laser Retro-reflector Array) will be delivered to JPL for deployment on the NASA Mars 2020 Rover. The first lunar landing opportunities will be from early 2018 (with TeamIndus) to late 2018 with commercial missions, followed by opportunities with space agency missions, including the proposed deployment of MoonLIGHT and INRRI on NASA’s Resource Prospectors and its evolutions. In conclusion, we will extend significantly the CCR Lunar Geophysical Network and populate the Mars Geophysical Network. These networks will enable very significantly improved tests of GR.

Keywords: general relativity, laser retroreflectors, lunar laser ranging, Mars geodesy

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Authors: Farrokh Taherkhani, Thomas Pinger, Max Gündel

Abstract:

Corrosion and suitable corrosion protection systems are a significant factor in the consideration of life cycle costs for steel hydraulic structures. In addition to classic coating systems (for example, epoxy resin or polyurethane), zinc and its alloys offer effective and very durable corrosion protection for steels. As a protective layer, hot-dip galvanizing prevents the corrosive media from penetrating into the steel matrix and acts as a sacrificial anode, which corrodes in preference to steel. However, hot-dip galvanizing as a corrosion protection system has not yet been approved by the relevant authority, the Federal Waterways Engineering and Research Institute (BAW) in Germany. In order to make hot-dip galvanizing usable as a corrosion protection system for steel hydraulic structures in the future, different factors must be considered. These factors are (i) corrosion protection type, (ii) resistance to mechanical stress (i.e., abrasion resistance), (iii) combinability with cathodic corrosion protection, (iv) environmental effects, and (v) the crack formation and propagation during hot-dip galvanizing. In this work, hot-dip galvanizing as a corrosion protection system for steel hydraulic steel structures, as well as open questions, are discussed. This paper is based on initial long-term exposure tests with corrosion protection systems consisting of hot-dip galvanizing and duplex systems.

Keywords: steel hydraulic structure, hot-dip galvanizing, corrosion resistance, zinc coating, organic coating and duplex systems

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Authors: Mohammad Abdallah

Abstract:

Due to the constant increase in terrorist attacks, the research and engineering communities have given significant attention to building performance under explosions. This paper presents a methodology for studying and simulating the dynamic responses of steel structures during external detonations, particularly for accurately investigating the impact of incrementing charge weight on the members total behavior, resistance and failure. Prediction damage method was introduced to evaluate the damage level of the steel members based on five scenarios of explosions. Johnson–Cook strength and failure model have been used as well as ABAQUS finite element code to simulate the explicit dynamic analysis, and antecedent field tests were used to verify the acceptance and accuracy of the proposed material strength and failure model. Based on the structural response, evaluation criteria such as deflection, vertical displacement, drift index, and damage level; the obtained results show the vulnerability of steel columns and un-braced steel frames which are designed and optimized to carry dead and live load to resist and endure blast loading.

Keywords: steel structure, blast load, terrorist attacks, charge weight, damage level

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Authors: Dhiaadin Bahaadin Noory

Abstract:

This research involves the effect of both sizes of reinforced zone and the amount of polypropylene fiber reinforcement on the structural behavior of model-reinforced sand loaded by square footing. The ratio of the side of the square reinforced zone to the footing width (W/B) and the ratio of the square reinforced zone depth to footing width (H/B) has been varied from one to six and from one to three, respectively. The tests were carried out on a small-scale laboratory model in which uniform-graded sand was used as a fill material. It was placed in a highly dense state by hitting a thin wooden board placed on the sand surface with a hammer. The sand was reinforced with randomly oriented discrete fibrillated polypropylene fibers. The test results indicated a significant increase in the bearing capacity and stiffness of the subgrade and a modification of load–the settlement behavior of sand with the size of the reinforced zone and amount of fiber reinforcement. On the basis of the present test results, the optimal side width and depth of the reinforced zone were 4B and 2B, respectively, while the optimal percentage of fibers was 0.4%.

Keywords: square footing, polypropylene fibers, bearing capacity, stiffness, load settlement behavior, relative density

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Authors: A. Guerrero, A. Leon, S. Munoz, M. Sandoval

Abstract:

The addition of solvent to cyclic steam stimulation is done in order to reduce the solvent-vapor ratio at late stages of the process, the moment in which this relationship increases significantly. The study of the use of naphtha in addition to the cyclic steam stimulation has been mainly oriented to the effect it achieves on the incremental recovery compared to the application of steam only. However, the effect of naphtha on the reactivity of crude oil components under conditions of cyclic steam stimulation or if its effect is the only dilution has not yet been considered, to author’s best knowledge. The present study aims to evaluate and understand the effect of naphtha and the conditions of cyclic steam stimulation, on the remaining composition of the improved oil, as well as the main mechanisms present in the heavy crude - naphtha interaction. Tests were carried out with the system solvent (naphtha)-oil (12.5° API, 4216 cP @ 40° C)- steam, in a batch micro-reactor, under conditions of cyclic steam stimulation (250-300 °C, 400 psi). The characterization of the samples obtained was carried out by MALDI-TOF MS (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) and NMR (Nuclear Magnetic Resonance) techniques. The results indicate that there is a rearrangement of the microstructure of asphaltenes, resulting in a decrease in these and an increase in lighter components such as resins.

Keywords: composition change, cyclic steam stimulation, interaction mechanism, naphtha

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Authors: Doufoungognon C. Kone

Abstract:

Global change, in particular pollution and global warming, threatens ecosystems and the biodiversity they harbor. Due to pollutants exposure, organisms might modify their thermal niches in order to track the thermal conditions limiting the negative impacts of chemical stressors depending on their mode of action. This study tests the influence of different pollutants, copper, salt, and chloramphenicol, on the thermal preferences of the ciliate Tetrahymena thermophila. Six genotypes were exposed to a gradient of concentrations ranging from 0 to 500mg/L for copper, 0 to 300 mg/l for chloramphenicol, and 0 to 12g/l for salt in synthetic media at eight temperatures ranging from 11 to 39° C. The measured fitness proxies are the maximum growth rate and the 50% growth inhibitory concentration (IC50). The results show that the majority of genotypes are more resistant to chloramphenicol in temperatures below their thermal optimum without pollutants, while they better tolerate other salt and copper in temperatures above their thermal optimum. In addition, generalists reduce their niche width while specialists widen it in chloramphenicol. Overall, results suggest that global warming would have a particularly deleterious effect in the case of chemical pollution. This pollution would induce the full disruption of the thermal habitats.

Keywords: ciliate, thermal niche, growth rate, toxicity, multiple stressors

Procedia PDF Downloads 89