Search results for: event study
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 48951

Search results for: event study

8421 Effect of Zinc Nanoparticles on Oxidative Stress-Related Genes and Antioxidant Enzymes Activity in the Brain of Oreochromis Niloticus and Tilapia Zillii

Authors: Salina Saddick, Mohamed Afifi, Osama Abuznadah

Abstract:

This study was carried out to determine the median lethal concentrations (LC50) of Zinc nanoparticles (ZnNPs) on Oreochromis niloticus and Tilapia zillii. The biochemical and molecular potential effects of ZnNPs (500 and 2000 μg L−1) on the antioxidant system in the brain tissue of O. niloticus and T. zillii were investigated. Four hundred fish were used for acute and sub-acute studies. ZnNP LC50 concentrations were investigated in O. niloticus and T. zillii. The effect of 500 and 2000 μg L−1 ZnNPs on brain antioxidants of O. niloticus and T. zillii was investigated. The result indicated that 69 h LC50 was 5.5 ± 0.6 and 5.6 ± 0.4 for O. nilotica and T. zillii, respectively. Fish exposed to 500 μg L−1 ZnNPs showed a significant increase in reduced glutathione (GSH), total glutathione (tGSH) levels, superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) activity and gene expression. On the contrary, malondialdehyde (MDA) levels significantly decreased. Meanwhile, fish exposed to 2000 μg L−1 ZnNPs showed a significant decrease of GSH, tGSH levels, SOD, CAT, GR, GPx and GST activity and gene expression. On the contrary, MDA levels significantly increased. It was concluded that, the 96 h LC50 of ZnNPs was 5.5 ± 0.6 and 5.6 ± 0.4 for O. nilotica and T. zillii, respectively. ZnNPs in exposure concentrations of 2000 μg/L induced a deleterious effect on the brain antioxidant system of O. nilotica and T. zillii. In contrast, ZnNPs in exposure concentrations of 500 μg L−1 produced an inductive effect on the brain antioxidant system of O. nilotica and T. zillii.

Keywords: ZnNPs, LC50, antioxidants, O. nilotica

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8420 Effect of External Radiative Heat Flux on Combustion Characteristics of Rigid Polyurethane Foam under Piloted-Ignition and Radiative Auto-Ignition Modes

Authors: Jia-Jia He, Lin Jiang, Jin-Hua Sun

Abstract:

Rigid polyurethane foam (RPU) has been extensively applied in building insulation system, yet with high flammability for being easily ignited by high temperature spark or radiative heat flux from other flaming materials or surrounding building facade. Using a cone calorimeter by Fire Testing Technology and thermal couple tree, this study systematically investigated the effect of radiative heat flux on the ignition time and characteristic temperature distribution during RPU combustion under different heat fluxes gradient (12, 15, 20, 25, 30, 35, 40, 45, and 50 kW/m²) with spark ignition/ignition by radiation. The ignition time decreases proportionally with increase of external heat flux, meanwhile increasing the external heat flux raises the peak heat release rate and impresses on the vertical temperature distribution greatly. The critical ignition heat flux is found to be 15 and 25 kW/m² for spark ignition and radiative ignition, respectively. Based on previous experienced ignition formula, a methodology to predict ignition times in both modes has been developed theoretically. By analyzing the heat transfer mechanism around the sample surroundings, both radiation from cone calorimeter and convection flow are considered and calculated theoretically. The experimental ignition times agree well with the theoretical ones in both radiative and convective conditions; however, the observed critical ignition heat flux is higher than the calculated one under piloted-ignition mode because the heat loss process, especially in lower heat flux radiation, is not considered in this developed methodology.

Keywords: rigid polyurethane foam, cone calorimeter, ignition time, external heat flux

Procedia PDF Downloads 179
8419 The Use of Surveys to Combat Fake News in Media Literacy Education

Authors: Jaejun Jong

Abstract:

Fake news has recently become a serious international problem. Therefore, researchers and policymakers worldwide have sought to understand fake news and develop strategies to combat it. This study consists of two primary parts: (1) a literature review of how surveys were used to understand fake news and identify problems caused by fake news, and (2) a discussion of how surveys were used to fight back against fake news in educational settings. This second section specifically analyzes surveys used to evaluate a South Korean elementary school program designed to improve students’ metacognition and critical thinking. This section seeks to identify potential problems that may occur in the elementary school setting. The literature review shows that surveys can help people to understand fake news based on its traits rather than its definition due to the lack of agreement on the definition of fake news. The literature review also shows that people are not good at identifying fake news or evaluating their own ability to identify fake news; indeed, they are more likely to share information that aligns with their previous beliefs. In addition, the elementary school survey data shows that there may be substantial errors in the program evaluation process, likely caused by processing errors or the survey procedure, though the exact cause is not specified. Such a significant error in evaluating the effects of the educational program prevents teachers from making proper decisions and accurately evaluating the program. Therefore, identifying the source of such errors would improve the overall quality of education, which would benefit both teachers and students.

Keywords: critical thinking, elementary education, program evaluation, survey

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8418 Development of High Strength Self Curing Concrete Using Super Absorbing Polymer

Authors: K. Bala Subramanian, A. Siva, S. Swaminathan, Arul. M. G. Ajin

Abstract:

Concrete is an essential building material which is widely used in construction industry all over the world due to its compressible strength. Curing of concrete plays a vital role in durability and other performance necessities. Improper curing can affect the concrete performance and durability easily. When areas like scarcity of water, structures is not accessible by humans external curing cannot be performed, so we opt for internal curing. Internal curing (or) self-curing plays a major role in developing the concrete pore structure and microstructure. The concept of internal curing is to enhance the hydration process to maintain the temperature uniformly. The evaporation of water in the concrete is reduced by self-curing agent (Super Absorbing Polymer – SAP) thereby increasing the water retention capacity of the concrete. The research work was carried out to reduce water, which is prime material used for concrete in the construction industry. Concrete curing plays a major role in developing hydration process. Concept of self-curing will reduce the evaporation of water from concrete. Self-curing will increase water retention capacity as compared to the conventional concrete. Proper self-curing (or) internal curing increases the strength, durability and performance of concrete. Super absorbing Polymer (SAP) used as internal curing agent. In this study 0.2% to 0.4% of SAP was varied in different grade of high strength concrete. In the experiment replacement of cement by silica fumes with 5%, 10% and 15% are studied. It is found that replacement of silica fumes by 10 % gives more strength and durability when compared to others

Keywords: compressive strength, high strength concrete rapid chloride permeability, super absorbing polymer

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8417 Kinetics Analysis of Lignocellulose Hydrolysis and Glucose Consumption Using Aspergillus niger in Solid State

Authors: Akida Mulyaningtyas, Wahyudi Budi Sediawan

Abstract:

One decisive stage in bioethanol production from plant biomass is the hydrolysis of lignocellulosic materials into simple sugars such as glucose. The produced glucose is then fermented into ethanol. This stage is popularly done in biological method by using cellulase that is produced by certain fungi. As it is known, glucose is the main source of nutrition for most microorganisms. Therefore, cutting cellulose into glucose is actually an attempt of microorganism to provide nutrition for itself. So far, this phenomenon has received less attention while it is necessary to identify the quantity of sugar consumed by the microorganism. In this study, we examined the phenomenon of sugar consumption by microorganism on lignocellulosic hydrolysis. We used oil palm empty fruit bunch (OPEFB) as the source of lignocellulose and Aspergillus niger as cellulase-producing fungus. In Indonesia, OPEFB is plantation waste that is difficult to decompose in nature and causes environmental problems. First, OPEFB was pretreated with 1% of NaOH at 170 oC to destroy lignin that hindered A.niger from accessing cellulose. The hydrolysis was performed by growing A.niger on pretreated OPEFB in solid state to minimize the possibility of contamination. The produced glucose was measured every 24 hours for 9 days. We analyzed the kinetics of both reactions, i.e., hydrolysis and glucose consumption, simultaneously. The constants for both reactions were assumed to follow the Monod equation. The results showed that the reaction constant of glucose consumption (μC) was higher than of cellulose hydrolysis (μH), i.e., 11.8 g/L and 0.62 g/L for glucose consumption and hydrolysis respectively. However, in general, the reaction rate of hydrolysis is greater than of glucose consumption since the cellulose concentration as substrate in hydrolysis is much higher than glucose as substrate in the consumption reaction.

Keywords: Aspergillus niger, bioethanol, hydrolysis, kinetics

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8416 Analysis of Rainfall and Malaria Trends in Limpopo Province, South Africa

Authors: Abiodun M. Adeola, Hannes Rautenbach, Gbenga J. Abiodun, Thabo E. Makgoale, Joel O. Botai, Omolola M. Adisa, Christina M. Botai

Abstract:

There was a surge in malaria morbidity as well as mortality in 2016/2017 malaria season in malaria-endemic regions of South Africa. Rainfall is a major climatic driver of malaria transmission and has potential use for predicting malaria. Annual and seasonal trends and cross-correlation analyses were performed on time series of monthly total rainfall (derived from interpolated weather station data) and monthly malaria cases in five districts of Limpopo Province for the period of 1998 to 2017. The time series analysis indicated that an average of 629.5mm of rainfall was received over the period of study. The rainfall has an annual variation of about 0.46%. Rainfall amount varies among the five districts, with the north-eastern part receiving more rainfall. Spearman’s correlation analysis indicated that total monthly rainfall with one to two months lagged effect is significant in malaria transmission in all the five districts. The strongest correlation is noticed in Mopani (r=0.54; p-value = < 0.001), Vhembe (r=0.53; p-value = < 0.001), Waterberg (r=0.40; p-value = < 0.001), Capricorn (r=0.37; p-value = < 0.001) and lowest in Sekhukhune (r=0.36; p-value = < 0.001). More particularly, malaria morbidity showed a strong relationship with an episode of rainfall above 5-year running means of rainfall of 400 mm. Both annual and seasonal analyses showed that the effect of rainfall on malaria varied across the districts and it is seasonally dependent. Adequate understanding of climatic variables dynamics annually and seasonally is imperative in seeking answers to malaria morbidity among other factors, particularly in the wake of the sudden spike of the disease in the province.

Keywords: correlation, malaria, rainfall, seasonal, trends

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8415 Thermal Hysteresis Activity of Ice Binding Proteins during Ice Crystal Growth in Sucrose Solution

Authors: Bercem Kiran-Yildirim, Volker Gaukel

Abstract:

Ice recrystallization (IR) which occurs especially during frozen storage is an undesired process due to the possible influence on the quality of products. As a result of recrystallization, the total volume of ice remains constant, but the size, number, and shape of ice crystals change. For instance, as indicated in the literature, the size of ice crystals in ice cream increases due to recrystallization. This results in texture deterioration. Therefore, the inhibition of ice recrystallization is of great importance, not only for food industry but also for several other areas where sensitive products are stored frozen, like pharmaceutical products or organs and blood in medicine. Ice-binding proteins (IBPs) have the unique ability to inhibit ice growth and in consequence inhibit recrystallization. This effect is based on their ice binding affinity. In the presence of IBP in a solution, ice crystal growth is inhibited during temperature decrease until a certain temperature is reached. The melting during temperature increase is not influenced. The gap between melting and freezing points is known as thermal hysteresis (TH). In literature, the TH activity is usually investigated under laboratory conditions in IBP buffer solutions. In product applications (e.g., food) there are many other solutes present which may influence the TH activity. In this study, a subset of IBPs, so-called antifreeze proteins (AFPs), is used for the investigation of the influence of sucrose solution concentration on the TH activity. For the investigation, a polarization microscope (Nikon Eclipse LV100ND) equipped with a digital camera (Nikon DS-Ri1) and a cold stage (Linkam LTS420) was used. In a first step, the equipment was established and validated concerning the accuracy of TH measurements based on literature data.

Keywords: ice binding proteins, ice crystals, sucrose solution, thermal hysteresis

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8414 InSAR Times-Series Phase Unwrapping for Urban Areas

Authors: Hui Luo, Zhenhong Li, Zhen Dong

Abstract:

The analysis of multi-temporal InSAR (MTInSAR) such as persistent scatterer (PS) and small baseline subset (SBAS) techniques usually relies on temporal/spatial phase unwrapping (PU). Unfortunately, it always fails to unwrap the phase for two reasons: 1) spatial phase jump between adjacent pixels larger than π, such as layover and high discontinuous terrain; 2) temporal phase discontinuities such as time varied atmospheric delay. To overcome these limitations, a least-square based PU method is introduced in this paper, which incorporates baseline-combination interferograms and adjacent phase gradient network. Firstly, permanent scatterers (PS) are selected for study. Starting with the linear baseline-combination method, we obtain equivalent 'small baseline inteferograms' to limit the spatial phase difference. Then, phase different has been conducted between connected PSs (connected by a specific networking rule) to suppress the spatial correlated phase errors such as atmospheric artifact. After that, interval phase difference along arcs can be computed by least square method and followed by an outlier detector to remove the arcs with phase ambiguities. Then, the unwrapped phase can be obtained by spatial integration. The proposed method is tested on real data of TerraSAR-X, and the results are also compared with the ones obtained by StaMPS(a software package with 3D PU capabilities). By comparison, it shows that the proposed method can successfully unwrap the interferograms in urban areas even when high discontinuities exist, while StaMPS fails. At last, precise DEM errors can be got according to the unwrapped interferograms.

Keywords: phase unwrapping, time series, InSAR, urban areas

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8413 The Posthuman Condition and a Translational Ethics of Entanglement

Authors: Shabnam Naderi

Abstract:

Traditional understandings of ethics considered translators, translations, technologies and other agents as separate and prioritized human agents. In fact, ethics was equated with morality. This disengaged understanding of ethics is superseded by an ethics of relation/entanglement in the posthuman philosophy. According to this ethics of entanglement, human and nonhuman agents are in constant ‘intra-action’. The human is not separate from nature, from technology and from other nonhuman entities, and an ethics of translation in this regard cannot be separated from technology and ecology and get defined merely within the realm of human-human encounter. As such, a posthuman ethics offers opportunities for change and responds to the changing nature of reality, it is negotiable and reveals itself as a moment-by-moment practice (i.e. as temporally emergent and beyond determinacy and permanence). Far from the linguistic or cultural, or individual concerns, posthuman translational ethics discusses how the former rigid norms and laws are challenged in a process ontology which puts emphasis on activity and activation and considers ethics as surfacing in activity, not as a predefined set of rules and values. In this sense, traditional ethical principles like faithfulness, accuracy and representation are superseded by principles of privacy, sustainability, multiplicity and decentralization. The present conceptual study, drawing on Ferrando’s philosophical posthumanism (as a post-humanism, as a post-dualism and as a post-anthropocentrism), Deleuze-Guattarian philosophy of immanence and Barad’s physics-philosophy strives to destabilize traditional understandings of translation ethics and bring an ethics that has loose ends and revolves around multiplicity and decentralization into the picture.

Keywords: ethics of entanglement, post-anthropocentrism, post-dualism, post-humanism, translation

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8412 Experiencing Scarred Body among Thai Women Living with Breast Cancer

Authors: Dusanee Suwankhong, Pranee Liamputtong

Abstract:

Breast surgery leaves undesirable scars to all women who experienced mastectomy, despite the fact that this could be a principle approach to save one life. This paper explores how Thai women living with breast cancer perceived and experienced a scarred body after breast surgery. In-depth interviews and drawing methods were employed among 20 women diagnosed with breast cancer. The interviewed data were analysed using thematic analysis method. The results showed that all women with breast cancer who underwent breast surgery perceived and experienced scar as a persisting and visible side-effect. This disfigurement appearance presented a negative image of feminine identity and led to emotional burdens among women. They responded to being scarred in different ways relating to their perceptions of body and changes. The older group had less embarrassed feelings towards being scarred comparing to the younger one. All women tried to seek means to cope with such physical impairment and keep balance life related to their condition. For example, they relied on Buddhism practice and tried to heal the keloid using natural products. Scars appeared to be an unpleasant effect for women who underwent breast mastectomy. Nurses and health care professionals in the local health service sectors need to pay close attention to how the women see the scarred body and their experiences of living with the distorted feminine appearance, and to provide sensitive support that meets the needs of these vulnerable women. The suitable supports can reduce the sense of embarrassment and increase their sense of self-confidence about their social femininity.

Keywords: breast surgery, emotional response, qualitative study, scars, Thai women

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8411 Influence of Sulphur and Boron on Growth, Quality Parameters and Productivity of Soybean (Glycine Max (L.) Merrill)

Authors: Shital Bangar, G. B. Khandagale

Abstract:

The experimentation was carried out to study the influence of sulphur and boron on growth parameters and productivity of soybean in kharif season of 2009-2010 at Experimental Farm, Department of Agricultural Botany, Marathwada Agricultural University, Parbhani (M.S.). The object was to evaluate the impact of sulphur and boron on growth, development, grain yield and physiological aspects of soybean variety MAUS-81. Nine treatments consisted of three levels of sulphur i.e. 20, 30 and 40 Kg/ha as well as three levels boron i.e.10, 15 and 20 kg boron/ha and the combinations of these two mineral elements i.e. Sulphur @30 kg/ha + Borax @15 kg/ha and Sulphur @40 kg/ha + Borax @ 20 kg/ha with one control treatment in Randomized Block Design (RBD) with three replications. The effect of sulphur and boron on various growth parameters of soybean like relative growth rate (RGR) and net assimilation rate (NAR) were remained statistically on par with each other. However, the application of higher dose of Sulphur @40 kg/ha + Borax @ 20 kg/ha enhanced significantly all the growth parameters. Application of the nutrients increased the dry matter accumulation of the crop plant and hence, other growth indices like RGR and NAR also increased significantly. RGR and NAR values were recorded highest at the initial crop growth stages and decline thereafter. The application of sulphur @40 kg/ha + Borax @ 20 kg/ha recorded significantly higher content of chlorophyll ‘a’ than rest of the treatments and chlorophyll ‘b’ observed higher in boron @15 kg/ha as well as boron@20 kg/ha, whereas total chlorophyll content was maximum in sulphur @40 kg/ha. Oil content was not influenced significantly due to above fertilization. The highest seed yield and total biological yield were obtained with combination of Sulphur @40 kg/ha + Borax @ 20 kg/ha, single sulphur and boron application also showed a significant effect on seed and biological yield.

Keywords: boron, growth, productivity, quality, soybean and sulphur

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8410 The Impact of Large-Scale Wind Energy Development on Islands’ Interconnection to the Mainland System

Authors: Marina Kapsali, John S. Anagnostopoulos

Abstract:

Greek islands’ interconnection (IC) with larger power systems, such as the mainland grid, is a crucial issue that has attracted a lot of interest; however, the recent economic recession that the country undergoes together with the highly capital intensive nature of this kind of projects have stalled or sifted the development of many of those on a more long-term basis. On the other hand, most of Greek islands are still heavily dependent on the lengthy and costly supply chain of oil imports whilst the majority of them exhibit excellent potential for wind energy (WE) applications. In this respect, the main purpose of the present work is to investigate −through a parametric study which varies both in wind farm (WF) and submarine IC capacities− the impact of large-scale WE development on the IC of the third in size island of Greece (Lesbos) with the mainland system. The energy and economic performance of the system is simulated over a 25-year evaluation period assuming two possible scenarios, i.e. S(a): without the contribution of the local Thermal Power Plant (TPP) and S(b): the TPP is maintained to ensure electrification of the island. The economic feasibility of the two options is investigated in terms of determining their Levelized Cost of Energy (LCOE) including also a sensitivity analysis on the worst/reference/best Cases. According to the results, Lesbos island IC presents considerable economic interest for covering part of island’s future electrification needs with WE having a vital role in this challenging venture.

Keywords: electricity generation cost, levelized cost of energy, mainland grid, wind energy rejection

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8409 Correlations between Pushing Skills and Pushing Perceptions, Second-Stage Labor Duration, Postpartum Fatigue, and Birth Satisfaction

Authors: Yu-Ching Huang

Abstract:

Background: Delivery bridges the antepartum and postpartum period. Subsequent fatigue can affect indices, including postpartum recovery and life quality. Milk secretion, breastfeeding quality, and newborn participation may be compromised. Correspondingly, using proper pushing skills during the second stage of labor has the potential to effectively reduce postpartum fatigue and enhance birth satisfaction in new mothers. Purpose: To compare the effects of using different pushing skills on maternal pushing perception, postpartum fatigue, and birth satisfaction. Methodology: The present study used a descriptive research approach and recruited 382 participants from a medical center in northern Taiwan. Data were collected using a structured questionnaire, which included a demographic and obstetrics information datasheet, the Labor Pushing Experience Scale, a fatigue scale, and a birth satisfaction scale. Research Results: Using pushing skills (including upright position [t= 2.28, p < .05] and delayed pushing [t= -1.98, p < .05] during the second stage of labor was shown to enhance birth satisfaction in participants. Additionally, open glottis pushing ( t = 5.46, p < .001) resulted in a mean duration of second-stage labor that was 17.67 minutes less than that achieved using Valsalva pushing. Moreover, a better perceived pushing experience was associated with lower perceived postpartum fatigue (r = .46, p < .05) and higher birth satisfaction (r = -.16, p < .05). Finally, postpartum fatigue perception was negatively associated with birth satisfaction (r = -.16, p < .05). Conclusion and Clinical Application: The findings suggest that midwives should advocate that women adopt upright positions, delayed pushing, and open glottis pushing during the second stage of labor in order to enhance their birth satisfaction.

Keywords: second stage labor duration of pushing skill, pushing experience perception, postpartum fatigue, birth satisfaction

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8408 Applying Lean Six Sigma in an Emergency Department, of a Private Hospital

Authors: Sarah Al-Lumai, Fatima Al-Attar, Nour Jamal, Badria Al-Dabbous, Manal Abdulla

Abstract:

Today, many commonly used Industrial Engineering tools and techniques are being used in hospitals around the world for the goal of producing a more efficient and effective healthcare system. A common quality improvement methodology known as Lean Six-Sigma has been successful in manufacturing industries and recently in healthcare. The objective of our project is to use the Lean Six-Sigma methodology to reduce waiting time in the Emergency Department (ED), in a local private hospital. Furthermore, a comprehensive literature review was conducted to evaluate the success of Lean Six-Sigma in the ED. According to the study conducted by Ibn Sina Hospital, in Morocco, the most common problem that patients complain about is waiting time. To ensure patient satisfaction many hospitals such as North Shore University Hospital were able to reduce waiting time up to 37% by using Lean Six-Sigma. Other hospitals, such as John Hopkins’s medical center used Lean Six-Sigma successfully to enhance the overall patient flow that ultimately decreased waiting time. Furthermore, it was found that capacity constraints, such as staff shortages and lack of beds were one of the main reasons behind long waiting time. With the use of Lean Six-Sigma and bed management, hospitals like Memorial Hermann Southwest Hospital were able to reduce patient delays. Moreover, in order to successfully implement Lean Six-Sigma in our project, two common methodologies were considered, DMAIC and DMADV. After the assessment of both methodologies, it was found that DMAIC was a more suitable approach to our project because it is more concerned with improving an already existing process. With many of its successes, Lean Six-Sigma has its limitation especially in healthcare; but limitations can be minimized if properly approached.

Keywords: lean six sigma, DMAIC, hospital, methodology

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8407 Performance Optimization on Waiting Time Using Queuing Theory in an Advanced Manufacturing Environment: Robotics to Enhance Productivity

Authors: Ganiyat Soliu, Glen Bright, Chiemela Onunka

Abstract:

Performance optimization plays a key role in controlling the waiting time during manufacturing in an advanced manufacturing environment to improve productivity. Queuing mathematical modeling theory was used to examine the performance of the multi-stage production line. Robotics as a disruptive technology was implemented into a virtual manufacturing scenario during the packaging process to study the effect of waiting time on productivity. The queuing mathematical model was used to determine the optimum service rate required by robots during the packaging stage of manufacturing to yield an optimum production cost. Different rates of production were assumed in a virtual manufacturing environment, cost of packaging was estimated with optimum production cost. An equation was generated using queuing mathematical modeling theory and the theorem adopted for analysis of the scenario is the Newton Raphson theorem. Queuing theory presented here provides an adequate analysis of the number of robots required to regulate waiting time in order to increase the number of output. Arrival rate of the product was fast which shows that queuing mathematical model was effective in minimizing service cost and the waiting time during manufacturing. At a reduced waiting time, there was an improvement in the number of products obtained per hour. The overall productivity was improved based on the assumptions used in the queuing modeling theory implemented in the virtual manufacturing scenario.

Keywords: performance optimization, productivity, queuing theory, robotics

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8406 Influence of Pseudomonas japonica on Growth and Metal Tolerance of Celosia cristata L.

Authors: Muhammad Umair Mushtaq, Ameena Iqbal, Muhammad Aqib Hassan Ali Khan, Ismat Nawaz, Sohail Yousaf, Mazhar Iqbal

Abstract:

Heavy metals are one of the priority pollutants as they pose serious health and environmental threats. They can be removed by various physiochemical methods but are costly and responsible for additional environmental problems. Bioremediation that exploits plants and their associated microbes have been referred as cost effective and environmental friendly technique. In this study, a pot experiment was conducted in a greenhouse to evaluate the potential of Celosia cristata and effects of bacteria, Pseudomonas japonica, and organic amendment moss/compost on tolerating/accumulating heavy metals. Two weeks old seedlings were transferred to soil in pots, and after four weeks they were inoculated with bacterial strain, while after growth of six weeks they were watered with a metal containing synthetic wastewater and were harvested after a growth period of nine weeks. After harvesting, morphological and physiological parameters and metal content of plants were measured. The results showed highest plant growth and biomass production in case of organic amendments while highest metal uptake has been found in non-amended pots. Positive controls have shown highest Pb uptake of 2900 mg/kg DW, while P. japonica amended pots have shown highest Cd, Cr, Ni and Cu uptake of 963.53, 1481.17, 1022.01 and 602.17 mg/kg DW, respectively. In conclusion organic amendments have strong impacts on growth enhancement while P. japonica enhances metal translocation and accumulation to aerial parts with little significant involvement in plant growth.

Keywords: ornamental plants, plant microbe interaction, amendments, bacteria

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8405 Chemical Characterization and Prebiotic Effect of Water-Soluble Polysaccharides from Zizyphus lotus Leaves

Authors: Zakaria Boual, Abdellah Kemassi, Toufik Chouana, Philippe Michaud, Mohammed Didi Ould El Hadj

Abstract:

In order to investigate the prebiotic potential of oligosaccharides prepared by chemical hydrolysis of water-soluble polysaccharides (WSP) from Zizyphus lotus leaves, the effect of oligosaccharides on bacterial growth was studied. The chemical composition of WSP was evaluated by colorimetric assays revealed the average values: 7.05±0.73% proteins and 86.21±0.74% carbohydrates, among them 64.81±0.42% are neutral sugar and the rest 16.25±1.62% are uronic acids. The characterization of monosaccharides was determined by high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) was found to be composed of galactose (23.95%), glucose (21.30%), rhamnose (20.28%), arabinose (9.55%), and glucuronic acid (22.95%). The effects of oligosaccharides on the growth of lactic acid bacteria were compared with those of fructo-oligosaccharide (RP95). The oligosaccharides concentration was 1g/L of man rogosa sharpe broth. Bacterial growth was assessed during 2, 4.5, 6.5, 9, 12, 16 and 24 h by measuring the optical density of the cultures at 600 nm (OD600) and pH values. During fermentation, pH in broth cultures decreased from 6.7 to 5.87±0.15. The enumeration of lactic acid bacteria indicated that oligosaccharides led to a significant increase in bacteria (P≤0.05) compared to the control. The fermentative metabolism appeared to be faster on RP95 than on oligosaccharides from Zizyphus lotus leaves. Both RP95 and oligosaccharides showed clear prebiotic effects, but had differences in fermentation kinetics because of to the different degree of polymerization. This study shows the prebiotic effectiveness of oligosaccharides, and provides proof for the selection of leaves of Zizyphus lotus for use as functional food ingredients.

Keywords: Zizyphus lotus, polysaccharides, characterization, prebiotic effects

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8404 Green Synthesis of Spinach Derived Carbon Dots for Photocatalytic Generation of Hydrogen from Sulfide Wastewater

Authors: Priya Ruban, Thirunavoukkarasu Manikkannan, Sakthivel Ramasamy

Abstract:

Sulfide is one of the major pollutants of tannery effluent which is mainly generated during the process of unhairing. Recovery of Hydrogen green fuel from sulfide wastewater using photocatalysis is a ‘Cleaner Production Method’, since renewable solar energy is utilized. It has triple advantages of the generation of H2, waste minimization and odor or pollution control. Designing of safe and green photocatalysts and developing suitable solar photoreactor is important for promoting this technology to large-scale application. In this study, green photocatalyst i.e., spinach derived carbon dots (SCDs 5 wt % and 10 wt %)/TiO2 nanocomposite was synthesized for generation of H2 from sulfide wastewater using lab-scale solar photocatalytic reactor. The physical characterization of the synthesized solar light responsive nanocomposites were studied by using DRS UV-Vis, XRD, FTIR and FESEM analysis. The absorption edge of TiO2 nanoparticles is extended to visible region by the incorporation of SCDs, which was used for converting noxious pollutant sulfide into eco-friendly solar fuel H2. The SCDs (10 wt%)-TiO2 nanocomposite exhibits enhanced photocatalytic hydrogen production i.e. ~27 mL of H2 (180 min) from simulated sulfide wastewater under LED visible light irradiation which is higher as compared to SCDs. The enhancement in the photocatalytic generation of H2 is attributed to combining of SCDs which increased the charge mobility. This work may provide new insights to usage of naturally available and cheap materials to design novel nanocomposite as a visible light active photocatalyst for the generation of H2 from sulfide containing wastewater.

Keywords: carbon dots, hydrogen fuel, hydrogen sulfide, photocatalysis, sulfide wastewater

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8403 Assessing the Risk of Pressure Injury during Percutaneous Nephrolithotomy Using Pressure Mapping

Authors: Jake Tempo, Taylor Smithurst, Jen Leah, Skye Waddingham, Amanda Catlin, Richard Cetti

Abstract:

Introduction: Percutaneous nephrolithotomy (PCNL) is the gold-standard procedure for removing large or complex renal stones. Many operating positions can be used, and the debate over the ideal position continues. PCNL can be a long procedure during which patients can sustain pressure injuries. These injuries are often underreported in the literature. Interface pressure mapping records the pressure loading between a surface and the patient. High pressures with prolonged loading result in ischaemia, muscle deformation, and reperfusion which can cause skin breakdown and muscular injury. We compared the peak pressure indexes of common PCNL positions to identify positions which may be at high risk of pressure injuries. We hope the data can be used to adapt high-risk positions so that the PPI can be lessened by either adapting the positions or by using adjuncts to lower PPI. Materials and Methods: We placed a 23-year-old male subject in fourteen different PCNL positions while performing interface pressure mapping. The subject was 179 cm with a weight of 63.3 kg, BMI 19.8kg/m². Results: Supine positions had a higher mean PPI (119mmHg (41-137)) compared to prone positions (64mmHg (32-89)) (p=0.046 two tailed t-test). The supine flexed position with a bolster under the flank produced the highest PPI (194mmHg), and this was at the sacrum. Peak pressure indexes >100mmHg were recorded in eight PCNL positions. Conclusion: Supine PCNL positions produce higher PPI than prone PCNL positions. Our study shows where ‘at risk’ bony prominences are for each PCNL position. Surgeons must ensure these areas are protected during prolonged operations.

Keywords: PCNL, pressure ulcer, interface pressure mapping, surgery

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8402 On the Differentiation of Strategic Spatial Planning Mechanisms in New Era: Between Melbourne and Tianjin

Authors: Zhao Liu, Kang Cao

Abstract:

Strategic spatial planning, which is taken as an effective and competitive way for the governors of the city to improve the development and management level of a city, has been blooming in recent years all over the world. In the context of globalization and informatization, strategic spatial planning must transfer its focus on three different levels: global, regional and urban. Internal and external changes in environmental conditions lead to new advances in strategic planning both theoretically and practically. However, such advances or changes respond differently to cities on account of different dynamic mechanisms. This article aims at two cities of Tianjin in China and Melbourne in Australia, through a comparative study on strategic planning, to explore the differentiation of mechanisms in urban planning. By comparison and exploration, the purpose of this article is to exhibit two different planning worlds, western and Chinese, in a new way. The article can be divided into four parts. The first part outlines strategic planning transformations in the new era on three levels, generally analysing the internal and external environmental factors of today. The second part indicates the concepts of strategic planning theoretically, demonstrating briefly its development background and process in western and China, respectively. The third part takes Tianjin and Melbourne urban strategic spatial planning as examples to mainly carry on the contrast research from the aspects of strategic planning mode, competitive mechanism, contents, strategy implementation and management. It is expected to summarize the differences and similarities of the two plans, meanwhile, to explore the inherent factors or mechanisms probably spatial, material, political and etc., which affect cities in the course of urban planning. The final part is a summary of general mechanisms of planning from the perspective of strategic spatial planning.

Keywords: differentiation, strategic planning, Melbourne, Australia, Tianjin, China

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8401 Use of Social Support for Fathers with Developmental Disabilities in Japan

Authors: Shiori Ishida, Hiromi Okuno, Hisato Igarashi, Akemi Yamazaki, Hiroko Takahashi

Abstract:

The purpose of this study was to clarify the differences and similarities regarding the social support of fathers and mothers towards considering increased assistance for the paternity of children with developmental disabilities. Written questionnaires were completed by fathers (n=85) and mothers (n=101) of children using rehabilitation facilities between infancy and 5 years of age. The survey contained multiple-choice questions on four categories: information support (6 items), emotional support (7 items), evaluation support (3 items), and daily living support (3 items). Regarding information support, fathers answered ‘spouse’ as the provider in over 50% of cases for all 6 items, which was significantly different compared with mothers (all p < 0.001). For emotional support, fathers were significantly more likely to get support from the workplace (p < 0.001) and from spouse (p < 0.001). The ‘evaluation support’ did not have significant differences for fathers in all the items, but the most frequent support providers were ‘spouses’. ‘Daily living support’ was significantly different from fathers in the workplace (p < 0.000) in terms of make allowances for work and duties. Thus, it appeared that fathers had fewer social support sources as compared with mothers and limited non-spouse support. The understanding of developmental disabilities, acquisition of methods of rehabilitation, and sources of support might have been inadequately addressed among fathers, which could be a hindrance to the involvement of fathers in the rearing of children with developmental disabilities. On the other hand, we also observed that some fathers were involved in the care of developmentally troubled children while providing mental support for their spouse, cooperating with housework, and adjusting their work life. However, the results on the external and social backgrounds of fathers indicated a necessity for greater empowerment and peer support to improve the paternal care of children with developmental disabilities in the family survey.

Keywords: children with developmental disabilities, family support, father, social support

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8400 Quantification Model for Capability Evaluation of Optical-Based in-Situ Monitoring System for Laser Powder Bed Fusion (LPBF) Process

Authors: Song Zhang, Hui Wang, Johannes Henrich Schleifenbaum

Abstract:

Due to the increasing demand for quality assurance and reliability for additive manufacturing, the development of an advanced in-situ monitoring system is required to monitor the process anomalies as input for further process control. Optical-based monitoring systems, such as CMOS cameras and NIR cameras, are proved as effective ways to monitor the geometrical distortion and exceptional thermal distribution. Therefore, many studies and applications are focusing on the availability of the optical-based monitoring system for detecting varied types of defects. However, the capability of the monitoring setup is not quantified. In this study, a quantification model to evaluate the capability of the monitoring setups for the LPBF machine based on acquired monitoring data of a designed test artifact is presented, while the design of the relevant test artifacts is discussed. The monitoring setup is evaluated based on its hardware properties, location of the integration, and light condition. Methodology of data processing to quantify the capacity for each aspect is discussed. The minimal capability of the detectable size of the monitoring set up in the application is estimated by quantifying its resolution and accuracy. The quantification model is validated using a CCD camera-based monitoring system for LPBF machines in the laboratory with different setups. The result shows the model to quantify the monitoring system's performance, which makes the evaluation of monitoring systems with the same concept but different setups possible for the LPBF process and provides the direction to improve the setups.

Keywords: data processing, in-situ monitoring, LPBF process, optical system, quantization model, test artifact

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8399 The Structural Pillars in Contemporary Mexico: Legacies of the Past and Lessons for the Future

Authors: Lisdey Espinoza Pedraza

Abstract:

In places from Latin America to Africa, a big number of authoritarian regimes have given way to democratic forces and increasingly responsive and open societies. Many countries have embarked upon a process of democratisation for the first time while many others have moved to restore their democratic roots. Mexico is one of these countries, and although the Mexican state is not democratic neither dictatorial in the strict sense the Anglo-Saxon and European tradition has defined these concepts, it is possible to find elements that combine both concepts. History helps us understand and study the past, interpret the present and predict the future. In the case of the Mexican political system, history has had a very specific effect in each of the areas that comprise the making of what it is now the contemporary Mexican system. Each of the different historical periods has left a legacy that has marked the way the political system has evolved. The historical periods that Mexico has undergone since its emergence as an independent state, have permeated until modern days and some of these legacies are the ones which will help us understand and interpret many of the structures of the current Mexican political system. The most notorious characteristic of contemporary Latin America is its dependency, underdevelopment and economic disparity once this region if compared with Europe and North America. There is a widespread persistence of economic dependence and social problems despite the creation of independent countries. The role of the state is to supervise the development of relations among actors. The political phenomenon is full of a constant process of transitions and the particular case of the formation of the Mexican state evidences this.

Keywords: Mexico, democratisation process, PRI, authoritarian regimes, political transitions, Latin America

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8398 Eugenol Effects on Metabolic Syndrome Induced Liver Damages

Authors: Fatemeh Kourkinejad Gharaei, Tahereh Safari, Zahra Saebinasab

Abstract:

Metabolic syndrome (MetS) is a set of risk factors associated with cardiovascular diseases, atherosclerosis, and type 2 diabetes. Nonalcoholic fatty liver disease (NAFLD) is the most important liver disorder in metabolic syndrome. High fructose consumption increases the risk of NAFLD. Eugenol shows anti-thrombotic, insulin-sensitive, fat-reducing effects. This study was designed to investigate the protective role of eugenol in NAFLD caused by metabolic syndrome. Methods: Thirty male Wistar rats were randomly divided into five groups; group 1, drinking water intake animals; group 2, fructose, group 3, fructose+eugenol solvent; group 4, fructose+ eugenol 50mg/kg and group 5, fructose+ eugenol 100mg/kg. At the end of the experiment, after 12 hours of fasting and under anesthesia, blood samples were taken for measurement of fast blood glucose (FBS), SGOT, AGPT, LDL, HDL, cholesterol, triglyceride. Results: FBG significantly increased in group 2 compared to group 1 (p < 0.001); however, it significantly decreased in groups 4 and 5 compared to group 2 (p < 0.05). SGOT and SGPT levels significantly increased in group 2 compared to drinking water alone (p < 0.001). However, SGOT and SGPT levels significantly decreased in groups 4 and 5. MDA and LTDS significantly increased in group 2 compared with drinking water alone (p < 0.01), while MDA and LTDS decreased in 4 and 5 groups compared to group 2 (p < 0.05), which confirms the pathology results related to the liver damage. Conclusion: Eugenol has protective effects on the liver and fat accumulation in liver cells.

Keywords: eugenol, fructose, metabolic syndrome, nonalcoholic fatty liver disease

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8397 Programmed Cell Death in Datura and Defensive Plant Response toward Tomato Mosaic Virus

Authors: Asma Alhuqail, Nagwa Aref

Abstract:

Programmed cell death resembles a real nature active defense in Datura metel against TMV after three days of virus infection. Physiological plant response was assessed for asymptomatic healthy and symptomatic infected detached leaves. The results indicated H2O2 and Chlorophyll-a as the most potential parameters. Chlorophyll-a was considered the only significant predictor variant for the H2O2 dependent variant with a P value of 0.001 and R-square of 0.900. The plant immune response was measured within three days of virus infection using the cutoff value of H2O2 (61.095 lmol/100 mg) and (63.201 units) for the tail moment in the Comet Assay. Their percentage changes were 255.12% and 522.40% respectively which reflects the stress of virus infection in the plant. Moreover, H2O2 showed 100% specificity and sensitivity in the symptomatic infected group using the receiver-operating characteristic (ROC). All tested parameters in the symptomatic infected group had significant correlations with twenty-five positive and thirty-one negative correlations where the P value was <0.05 and 0.01. Chlorophyll-a parameter had a crucial role of highly significant correlation between total protein and salicylic acid. Contrarily, this correlation with tail moment unit was (r = _0.930, P <0.01) where the P value was < 0.01. The strongest significant negative correlation was between Chlorophyll-a and H2O2 at P < 0.01, while moderate negative significant correlation was seen for Chlorophyll-b where the P value < 0.05. The present study discloses the secret of the three days of rapid transient production of activated oxygen species (AOS) that was enough for having potential quantitative physiological parameters for defensive plant response toward the virus.

Keywords: programmed cell death, plant–adaptive immune response, hydrogen peroxide (H2O2), physiological parameters

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8396 Psychological Contract and Job Embeddedness Perspectives to Understand Cynicism as a Behavioural Response to Pressures in the Workplace

Authors: Merkouche Wassila, Marchand Alain, Renaud Stéphane

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Organizations are facing competitive pressures constraining them to modify their practices and change initial work conditions of employees, however, these modifications have to sustain initial quality of work and engagements toward the workforce. We focus on the importance of promises in the perspective of psychological contract. According to this perspective, employees perceiving a breach of the expected obligations from the employer may become unsatisfied at work and develop organizational withdrawal behaviors. These are negative counterproductive behaviours aiming to damage the organisation according to the principle of reciprocity and social exchange. We present an integrative model of the determinants and manifestations of organizational withdrawal (OW), a set of behaviors allowing the employee to leave his job or avoid his assigned work. OW contains two main components often studied in silos: work withdrawal (delays, absenteeism and other adverse behaviors) and job withdrawal (turnover). We use the systemic micro, meso and macro sociological approach designing the individual at the heart of a system containing individual, organizational, and environmental determinants. Under the influence of these different factors, the individual assesses the type of behavior to adopt. We provide better lighting for understanding OW using both psychological contract approach through the perception of its respect by the organization and job embeddedness approach which explains why the employee does not leave the organization and then remains in his post while practicing negative and counterproductive behaviors such as OW. We study specifically cynicism as a type of OW as it is a dimension of burnout. We focus on the antecedents of cynicism to try to prevent it in the workplace.

Keywords: burnout, cynicism, job embeddedness, organizational withdrawal, psychological contract

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8395 The Femoral Eversion Endarterectomy Technique with Transection: Safety and Efficacy

Authors: Hansraj Riteesh Bookun, Emily Maree Stevens, Jarryd Leigh Solomon, Anthony Chan

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Objective: This was a retrospective cross-sectional study evaluating the safety and efficacy of femoral endarterectomy using the eversion technique with transection as opposed to the conventional endarterectomy technique with either vein or synthetic patch arterioplasty. Methods: Between 2010 to mid 2017, 19 patients with mean age of 75.4 years, underwent eversion femoral endarterectomy with transection by a single surgeon. There were 13 males (68.4%), and the comorbid burden was as follows: ischaemic heart disease (53.3%), diabetes (43.8%), stage 4 kidney impairment (13.3%) and current or ex-smoking (73.3%). The indications were claudication (45.5%), rest pain (18.2%) and tissue loss (36.3%). Results: The technical success rate was 100%. One patient required a blood transfusion following bleeding from intraoperative losses. Two patients required blood transfusions from low post operative haemogloblin concentrations – one of them in the context of myelodysplastic syndrome. There were no unexpected returns to theatre. The mean length of stay was 11.5 days with two patients having inpatient stays of 36 and 50 days respectively due to the need for rehabilitation. There was one death unrelated to the operation. Conclusion: The eversion technique with transection is safe and effective with low complication rates and a normally expected length of stay. It poses the advantage of not requiring a synthetic patch. This technique features minimal extraneous dissection as there is no need to harvest vein for a patch. Additionally, future endovascular interventions can be performed by puncturing the native vessel. There is no change to the femoral bifurcation anatomy after this technique. We posit that this is a useful adjunct to the surgeon’s panoply of vascular surgical techniques.

Keywords: endarterectomy, eversion, femoral, vascular

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8394 Removal of Nickel and Vanadium from Crude Oil by Using Solvent Extraction and Electrochemical Process

Authors: Aliya Kurbanova, Nurlan Akhmetov, Abilmansur Yeshmuratov, Yerzhigit Sugurbekov, Ramiz Zulkharnay, Gulzat Demeuova, Murat Baisariyev, Gulnar Sugurbekova

Abstract:

Last decades crude oils have tended to become more challenge to process due to increasing amounts of sour and heavy crude oils. Some crude oils contain high vanadium and nickel content, for example Pavlodar LLP crude oil, which contains more than 23.09 g/t nickel and 58.59 g/t vanadium. In this study, we used two types of metal removing methods such as solvent extraction and electrochemical. The present research is conducted for comparative analysis of the deasphalting with organic solvents (cyclohexane, carbon tetrachloride, chloroform) and electrochemical method. Applying the cyclic voltametric analysis (CVA) and Inductively coupled plasma mass spectrometry (ICP MS), these mentioned types of metal extraction methods were compared in this paper. Maximum efficiency of deasphalting, with cyclohexane as the solvent, in Soxhlet extractor was 66.4% for nickel and 51.2% for vanadium content from crude oil. Percentage of Ni extraction reached maximum of approximately 55% by using the electrochemical method in electrolysis cell, which was developed for this research and consists of three sections: oil and protonating agent (EtOH) solution between two conducting membranes which divides it from two capsules of 10% sulfuric acid and two graphite electrodes which cover all three parts in electrical circuit. Ions of metals pass through membranes and remain in acid solutions. The best result was obtained in 60 minutes with ethanol to oil ratio 25% to 75% respectively, current fits into the range from 0.3A to 0.4A, voltage changed from 12.8V to 17.3V.

Keywords: demetallization, deasphalting, electrochemical removal, heavy metals, petroleum engineering, solvent extraction

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8393 Error Detection and Correction for Onboard Satellite Computers Using Hamming Code

Authors: Rafsan Al Mamun, Md. Motaharul Islam, Rabana Tajrin, Nabiha Noor, Shafinaz Qader

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In an attempt to enrich the lives of billions of people by providing proper information, security and a way of communicating with others, the need for efficient and improved satellites is constantly growing. Thus, there is an increasing demand for better error detection and correction (EDAC) schemes, which are capable of protecting the data onboard the satellites. The paper is aimed towards detecting and correcting such errors using a special algorithm called the Hamming Code, which uses the concept of parity and parity bits to prevent single-bit errors onboard a satellite in Low Earth Orbit. This paper focuses on the study of Low Earth Orbit satellites and the process of generating the Hamming Code matrix to be used for EDAC using computer programs. The most effective version of Hamming Code generated was the Hamming (16, 11, 4) version using MATLAB, and the paper compares this particular scheme with other EDAC mechanisms, including other versions of Hamming Codes and Cyclic Redundancy Check (CRC), and the limitations of this scheme. This particular version of the Hamming Code guarantees single-bit error corrections as well as double-bit error detections. Furthermore, this version of Hamming Code has proved to be fast with a checking time of 5.669 nanoseconds, that has a relatively higher code rate and lower bit overhead compared to the other versions and can detect a greater percentage of errors per length of code than other EDAC schemes with similar capabilities. In conclusion, with the proper implementation of the system, it is quite possible to ensure a relatively uncorrupted satellite storage system.

Keywords: bit-flips, Hamming code, low earth orbit, parity bits, satellite, single error upset

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8392 The Effect of Accounting Conservatism on Cost of Capital: A Quantile Regression Approach for MENA Countries

Authors: Maha Zouaoui Khalifa, Hakim Ben Othman, Hussaney Khaled

Abstract:

Prior empirical studies have investigated the economic consequences of accounting conservatism by examining its impact on the cost of equity capital (COEC). However, findings are not conclusive. We assume that inconsistent results of such association may be attributed to the regression models used in data analysis. To address this issue, we re-examine the effect of different dimension of accounting conservatism: unconditional conservatism (U_CONS) and conditional conservatism (C_CONS) on the COEC for a sample of listed firms from Middle Eastern and North Africa (MENA) countries, applying quantile regression (QR) approach developed by Koenker and Basset (1978). While classical ordinary least square (OLS) method is widely used in empirical accounting research, however it may produce inefficient and bias estimates in the case of departures from normality or long tail error distribution. QR method is more powerful than OLS to handle this kind of problem. It allows the coefficient on the independent variables to shift across the distribution of the dependent variable whereas OLS method only estimates the conditional mean effects of a response variable. We find as predicted that U_CONS has a significant positive effect on the COEC however, C_CONS has a negative impact. Findings suggest also that the effect of the two dimensions of accounting conservatism differs considerably across COEC quantiles. Comparing results from QR method with those of OLS, this study throws more lights on the association between accounting conservatism and COEC.

Keywords: unconditional conservatism, conditional conservatism, cost of equity capital, OLS, quantile regression, emerging markets, MENA countries

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