Search results for: seismic capacity assessment
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10109

Search results for: seismic capacity assessment

7199 Numerical Simulation of Axially Loaded to Failure Large Diameter Bored Pile

Authors: M. Ezzat, Y. Zaghloul, T. Sorour, A. Hefny, M. Eid

Abstract:

Ultimate capacity of large diameter bored piles is usually determined from pile loading tests as recommended by several international codes and foundation design standards. However, loading of this type of piles till achieving apparent failure is practically seldom. In this paper, numerical analyses are carried out to simulate load test of a large diameter bored pile performed at the location of Alzey highway bridge project (Germany). Test results of pile load settlement relationship till failure as well as results of the base and shaft resistances are available. Apparent failure was indicated in this test by the significant increase of the induced settlement during the last load increment applied on the pile head. Measurements of this pile load test are used to assess the quality of the numerical models investigated. Three different material soil models are implemented in the analyses: Mohr coulomb (MC), Soft soil (SS), and Modified Mohr coulomb (MMC). Very good agreement is obtained between the field measured settlement and the calculated settlement using the MMC model. Results of analysis showed also that the MMC constitutive model is superior to MC, and SS models in predicting the ultimate base and shaft resistances of the large diameter bored pile. After calibrating the numerical model, behavior of large diameter bored piles under axial loads is discussed and the formation of the plastic zone around the pile is explored. Results obtained showed that the plastic zone below the base of the pile at failure extended laterally to about four times the pile diameter and vertically to about three times the pile diameter.

Keywords: ultimate capacity, large diameter bored piles, plastic zone, failure, pile load test

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7198 Exergy Analysis of Poultry Litter-to-Energy Production by the Advanced Combustion System

Authors: Samuel Oludayo Alamu, Seong Lee

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The need for generating energy from biomass in an efficient way as well as maximizing the yield of total energy from the thermal conversion process has been a major concern for researchers. A holistic approach which involves the combination of First law of thermodynamics (FLT) and the second law of thermodynamics (SLT) is required for conducting an effective assessment of an energy plant since FLT analysis alone fails to identify the quality of the dissipated energy and how much work potential is available. The overall purpose of this study is to investigate the exergy analysis of direct combustion of poultry waste being converted to energy with a handful of environmental assessment of the conversion processes in order to maximize thermal efficiency. The exergy analysis around the shell and tube heat exchanger (STHE) was investigated primarily by varying the operating parameters for different tube shapes and flow direction, and an exergy model was obtained from estimations of the higher heating value and standard entropy of poultry waste from the elemental compositions. The STHE was designed and fabricated by Lee Research Group at Morgan State University. The analysis conducted on theSTHE using the flue gas temperature entering and exiting show that only about one-third of the energy input to the STHE was available to do work with an overall efficiency of 13.8%, while a huge amount was lost to the surrounding. By recirculating the flue gas, the exergy efficiency of the combustion system can be maximized with a greater reduction in the amount of exergy loss.

Keywords: exergy analysis, shell and tube heat exchanger, thermodynamics, combustion system, thermal efficiency

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7197 Derivation of a Risk-Based Level of Service Index for Surface Street Network Using Reliability Analysis

Authors: Chang-Jen Lan

Abstract:

Current Level of Service (LOS) index adopted in Highway Capacity Manual (HCM) for signalized intersections on surface streets is based on the intersection average delay. The delay thresholds for defining LOS grades are subjective and is unrelated to critical traffic condition. For example, an intersection delay of 80 sec per vehicle for failing LOS grade F does not necessarily correspond to the intersection capacity. Also, a specific measure of average delay may result from delay minimization, delay equality, or other meaningful optimization criteria. To that end, a reliability version of the intersection critical degree of saturation (v/c) as the LOS index is introduced. Traditionally, the level of saturation at a signalized intersection is defined as the ratio of critical volume sum (per lane) to the average saturation flow (per lane) during all available effective green time within a cycle. The critical sum is the sum of the maximal conflicting movement-pair volumes in northbound-southbound and eastbound/westbound right of ways. In this study, both movement volume and saturation flow are assumed log-normal distributions. Because, when the conditions of central limit theorem obtain, multiplication of the independent, positive random variables tends to result in a log-normal distributed outcome in the limit, the critical degree of saturation is expected to be a log-normal distribution as well. Derivation of the risk index predictive limits is complex due to the maximum and absolute value operators, as well as the ratio of random variables. A fairly accurate functional form for the predictive limit at a user-specified significant level is yielded. The predictive limit is then compared with the designated LOS thresholds for the intersection critical degree of saturation (denoted as X

Keywords: reliability analysis, level of service, intersection critical degree of saturation, risk based index

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7196 The Feasibility Evaluation Of The Compressed Air Energy Storage System In The Porous Media Reservoir

Authors: Ming-Hong Chen

Abstract:

In the study, the mechanical and financial feasibility for the compressed air energy storage (CAES) system in the porous media reservoir in Taiwan is evaluated. In 2035, Taiwan aims to install 16.7 GW of wind power and 40 GW of photovoltaic (PV) capacity. However, renewable energy sources often generate more electricity than needed, particularly during winter. Consequently, Taiwan requires long-term, large-scale energy storage systems to ensure the security and stability of its power grid. Currently, the primary large-scale energy storage options are Pumped Hydro Storage (PHS) and Compressed Air Energy Storage (CAES). Taiwan has not ventured into CAES-related technologies due to geological and cost constraints. However, with the imperative of achieving net-zero carbon emissions by 2050, there's a substantial need for the development of a considerable amount of renewable energy. PHS has matured, boasting an overall installed capacity of 4.68 GW. CAES, presenting a similar scale and power generation duration to PHS, is now under consideration. Taiwan's geological composition, being a porous medium unlike salt caves, introduces flow field resistance affecting gas injection and extraction. This study employs a program analysis model to establish the system performance analysis capabilities of CAES. The finite volume model is then used to assess the impact of porous media, and the findings are fed back into the system performance analysis for correction. Subsequently, the financial implications are calculated and compared with existing literature. For Taiwan, the strategic development of CAES technology is crucial, not only for meeting energy needs but also for decentralizing energy allocation, a feature of great significance in regions lacking alternative natural resources.

Keywords: compressed-air energy storage, efficiency, porous media, financial feasibility

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7195 Acanthopanax koreanum and Major Ingredient, Impressic Acid, Possess Matrix Metalloproteinase-13 Down-Regulating Capacity and Protect Cartilage Destruction

Authors: Hyun Lim, Dong Sook Min, Han Eul Yun, Kil Tae Kim, Ya Nan Sun, Young Ho Kim, Hyun Pyo Kim

Abstract:

Matrix metalloproteinase (MMP)-13 has an important role for degrading cartilage materials under inflammatory conditions such as arthritis. Since the 70% ethanol extract of Acanthopanax koreanum inhibited MMP-13 expression in IL-1β-treated human chondrocyte cell line, SW1353, two major constituents including acanthoic acid and impressic acid were initially isolated from the same plant materials and their MMP-13 down-regulating capacity was examined. In IL-1β-treated SW1353 cells, acanthoic acid and impressic acid significantly and concentration-dependently inhibited MMP-13 expression at 10 – 100 μM and 0.5 – 10 μM, respectively. The potent one, impressic acid, was found to inhibit MMP-13 expression by blocking the phosphorylation of signal transducer and activator of transcription-1/-2 (STAT-1/-2) and activation of c-Jun and c-Fos among cellular signaling pathway involved, but did not affect the activation of mitogen-activated protein kinases (MAPKs) and nuclear transcription factor-κB (NF-κB). Further, impressic acid was also found to inhibit the expression of MMP-13 mRNA (47.7% inhibition at 10 μM), the glycosaminoglycan release (42.2% reduction at 10 μM) and proteoglycan loss in IL-1-treated rabbit cartilage explants culture. For a further study, 21 impressic acid derivatives were isolated from the same plant materials and their suppressive activities against MMP-13 expression were examined. Among the derivatives, 3α-hydroxy-lup-20(29)-en-23-oxo,28-oic acid, (20R)-3α-hydroxy-29-dimethoxylupan-23,28-dioic acid, acankoreoside F and acantrifoside A clearly down-regulated MMP-13 expression, but impressic acid being most potent. All these results suggest that impressic acid, 3α-hydroxy-lup-20(29)-en-23-oxo,28-oic acid, (20R)-3α-hydroxy-29-dimethoxylupan-23,28-dioic acid, acankoreoside F, acantrifoside A and A. koreanum may have a potential for therapeutic agents to prevent cartilage degradation possibly by inhibiting matrix protein degradation.

Keywords: acanthoic acid, Acanthopanax koreanum, cartilage, impressic acid, matrix metalloproteinase

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7194 Seasonal Variations, Environmental Parameters, and Standing Crop Assessment of Benthic Foraminifera in Western Bahrain, Arabian Gulf

Authors: Muhammad Arslan, Michael A. Kaminski, Bassam S. Tawabini, Fabrizio Frontalini

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We conducted a survey of living benthic foraminifera in a relatively unpolluted site of Bahrain in the Arabian Gulf, with the aim of determining the seasonal variability in their populations, as well as various environmental parameters that affect their distribution. The maximum standing crop was observed during winter, with highest population of rotaliids, followed by a peak in miliolids. The highest population is attributed to an increasing number juveniles observed along the depth transect. A strong correlation between sediment grain size and the foraminiferal population indicates that juveniles were most abundant on coarser sandy substrate and less abundant on fine substrate. In spring, the total living population decreased, and lowest values are observed in the summer. The population started to increase again in the autumn with highest juveniles/adult ratios. Moreover, results of relative abundance and species consistency show that Ammonia is found to be consistent from the shallowest to the deepest station, whereas miliolids start appearing in the deeper stations. The average numbers of Peneroplis and Elphidium also increases along the depth transect. Environmental characterization reveals that although the site is subjected to eutrophication caused by nitrates and sulfates, pollution caused by hydrocarbons and heavy metals is not significant. The assessment of 63 heavy metals showed that none of the metals had concentrations that exceed internationally accepted norms [the devised level of Effect Range-Low], with the exception of strontium. The lack of a significant environmental effect of heavy metals is confirmed by a Foraminiferal Deformities Index value of less than 2%. Likewise, no hydrocarbon contamination was detected in the water or sediment samples. Lastly, observations of cytoplasmic streaming and pseudopodial activity in Petri dishes suggest that the foraminiferal population is not stressed. We conclude that the site in Bahrain is not yet adversely affected by human development, and therefore can provide baseline information for future comparison and assessment of foraminiferal assemblages in contaminated zones of the Arabian Gulf.

Keywords: Arabian Gulf, benthic foraminifera, standing crop, Western Bahrain

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7193 Institutional Effectiveness in Fostering Student Retention and Success in First Year

Authors: Naziema B. Jappie

Abstract:

The objective of this study is to examine the relationship between college readiness characteristics and learning outcome assessment scores. About this, it is important to examine the first-year retention and success rate. In order to undertake this study, it will be necessary to look at proficiency levels on general and domain-specific knowledge and skills reflected on national benchmark test scores (NBT), in-college interventions and course-taking patterns. Preliminary results based on data from more than 1000 students suggest that there is a positive association between NBT scores and students’ 1st-year college GPA and their retention status. For example, 63% of students with a proficient level of math skills in the NBT had the highest level of GPA at the end of 1st-year of college in comparison to 56% of those who started with a primary or intermediate level, respectively. The retention rates among those with proficiency levels were also higher than those with basic or intermediate levels (98% vs. 93% and 88%, respectively). By the end of 3rd year in college, students with intermediate or proficient entering NBT math skills had 7% and 8% of dropout rate, compared to 14% for those started at primary level; a greater percentage of students qualified by the end of 3rd-year qualified among proficient students than that among intermediate or basic level students (50% vs. 44% and 27% respectively). The findings of this study added knowledge to the field in South Africa and are expected to help stakeholders and policymakers to better understand college learning and challenges for students with disadvantaged backgrounds and provide empirical evidence in support of related practices and policies.

Keywords: assessment, data analysis, performance, proficiency, policy, student success

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7192 Food and Nutritional Security in the Context of Climate Change in Ethiopia: Using Household Panel Data

Authors: Aemro Tazeze Terefe, Mengistu K. Aredo, Abule M. Workagegnehu, Wondimagegn M. Tesfaye

Abstract:

Climate-induced shocks have been shown to reduce agricultural production and cause fluctuation in output in developing countries. When livelihoods depend on rain-fed agriculture, climate-induced shocks translate into consumption shocks. Despite the substantial improvements in household consumption, climate-induced shocks, and other factors adversely affect consumption dynamics at the household level in Ethiopia. Therefore, household consumption dynamics in the context of climate-induced shocks help to guide resilience capacity and establish appropriate interventions and programs. The research employed three-round panel data based on the Ethiopian Socioeconomic Survey with spatial rainfall data to define unique measures of rainfall variability. The linear dynamic panel model results show that the lagged value of consumption, market shocks, and rainfall variability positively affected consumption dynamics. In contrast, production shocks, temperature, and amount of rainfall had a negative relationship. Coping strategies mitigate adverse climate-induced shocks on consumption aftershocks that smooth consumption over time. Support to increase the resilience capacity of households can involve efforts to make existing livelihoods and forms of production or reductions in the vulnerability of households. Therefore, government interventions are mandatory for asset accumulation agendas that support household coping strategies and respond to shocks. In addition, the dynamic linkage between consumption and significant socioeconomic and institutional factors should be taken into account to minimize the effect of climate-induced shocks on consumption dynamics.

Keywords: climate shock, Ethiopia, fixed-effect model, food security

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7191 Intensity of Dyspnea and Anxiety in Seniors in the Terminal Phase of the Disease

Authors: Mariola Głowacka

Abstract:

Aim: The aim of this study was to present the assessment of dyspnea and anxiety in seniors staying in the hospice in the context of the nurse's tasks. Materials and methods: The presented research was carried out at the "Hospicjum Płockie" Association of St. Urszula Ledóchowska in Płock, in a stationary ward, for adults. The research group consisted of 100 people, women, and men. In the study described in this paper, the method of diagnostic survey, the method of estimation and analysis of patient records were used, and the research tools were the numerical scale of the NRS assessment, the modified Borg scale to assess dyspnea, the Trait Anxiety scale to test the intensity of anxiety and the sociodemographic assessment of the respondent. Results: Among the patients, the greatest number were people without dyspnoea (38 people) and with average levels of dyspnoea (26 people). People with lung cancer had a higher level of breathlessness than people with other cancers. Half of the patients included in the study felt anxiety at a low level. On average, men had a higher level of anxiety than women. Conclusion: 1) Patients staying in the hospice require comprehensive nursing care due to the underlying disease, comorbidities, and a wide range of medications taken, which aggravate the feeling of dyspnea and anxiety. 2) The study showed that in patients staying in the hospice, the level of dyspnea was of varying severity. The greatest number of people were without dyspnea (38) and patients with a low level of dyspnea (34). There were 12 people experiencing an average level of dyspnea and a high level of dyspnea 15. 3) The main factor influencing the severity of dyspnea in patients was the location of cancer. There was no significant relationship between the intensity of dyspnea and the age, gender of the patient, and time from diagnosis. 4) The study showed that in patients staying in the hospice, the level of anxiety was of varying severity. Most people experience a low level of anxiety (51). There were 16 people with a high level of anxiety, while there were 33 people experiencing anxiety at an average level. 5) The patient's gender was the main factor influencing the increase in anxiety intensity. Men had higher levels of anxiety than women. There was no significant correlation between the intensity of anxiety and the age of the respondents, as well as the type of cancer and time since diagnosis. 6) The intensity of dyspnea depended on the type of cancer the subjects had. People with lung cancer had a higher level of breathlessness than those with breast cancer and bowel cancer. It was not found that the anxiety increased depending on the type of cancer and comorbidities of the examined person.

Keywords: cancer, shortness of breath, anxiety, senior, hospice

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7190 Assessment of DNA Degradation Using Comet Assay: A Versatile Technique for Forensic Application

Authors: Ritesh K. Shukla

Abstract:

Degradation of biological samples in terms of macromolecules (DNA, RNA, and protein) are the major challenges in the forensic investigation which misleads the result interpretation. Currently, there are no precise methods available to circumvent this problem. Therefore, at the preliminary level, some methods are urgently needed to solve this issue. In this order, Comet assay is one of the most versatile, rapid and sensitive molecular biology technique to assess the DNA degradation. This technique helps to assess DNA degradation even at very low amount of sample. Moreover, the expedient part of this method does not require any additional process of DNA extraction and isolation during DNA degradation assessment. Samples directly embedded on agarose pre-coated microscopic slide and electrophoresis perform on the same slide after lysis step. After electrophoresis microscopic slide stained by DNA binding dye and observed under fluorescent microscope equipped with Komet software. With the help of this technique extent of DNA degradation can be assessed which can help to screen the sample before DNA fingerprinting, whether it is appropriate for DNA analysis or not. This technique not only helps to assess degradation of DNA but many other challenges in forensic investigation such as time since deposition estimation of biological fluids, repair of genetic material from degraded biological sample and early time since death estimation could also be resolved. With the help of this study, an attempt was made to explore the application of well-known molecular biology technique that is Comet assay in the field of forensic science. This assay will open avenue in the field of forensic research and development.

Keywords: comet assay, DNA degradation, forensic, molecular biology

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7189 Disaster Adaptation Mechanism and Disaster Prevention Adaptation Planning Strategies for Industrial Parks in Response to Climate Change and Different Socio-Economic Disasters

Authors: Jen-Te Pai, Jao-Heng Liu, Shin-En Pai

Abstract:

The impact of climate change has intensified in recent years, causing Taiwan to face higher frequency and serious natural disasters. Therefore, it is imperative for industrial parks manufacturers to promote adaptation policies in response to climate change. On the other hand, with the rise of the international anti-terrorism situation, once a terrorist attack occurs, it will attract domestic and international media attention, especially the strategic and economic status of the science park. Thus, it is necessary to formulate adaptation and mitigation strategies under climate change and social economic disasters. After reviewed the literature about climate change, urban disaster prevention, vulnerability assessment, and risk communication, the study selected 62 industrial parks compiled by the Industrial Bureau of the Ministry of Economic Affairs of Taiwan as the research object. This study explored the vulnerability and disaster prevention and disaster relief functional assessment of these industrial parks facing of natural and socio-economic disasters. Furthermore, this study explored planned adaptation of industrial parks management section and autonomous adaptation of corporate institutions in the park. The conclusion of this study is that Taiwan industrial parks with a higher vulnerability to natural and socio-economic disasters should employ positive adaptive behaviours.

Keywords: adaptive behaviours, analytic network process, vulnerability, industrial parks

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7188 Caring for a Spinal Cord Injury Patient with Diabetic Nephropathy Receiving Hospice Palliative Care

Authors: Li-Ting Kung, Hui-Zhu Chen, Hsin-Tzu Lee, Wan-Yin Hsu

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Patients with spinal cord injury combined with diabetic nephropathy may under a lot of painful conditions due to complications related to the illness itself or treatments, such as recurrent pressure ulcers, autonomic and peripheral neuropathy, as well as dialysis, for long term. This case report illustrated the nursing experience of transferring a spine cord injure patient who received hemodialysis due to adverse lifestyle-induced diabetic nephropathy to the hospice ward. Nursing care was provided in this patient from July 25th to August 30th, 2015. The tool of 'Gordon’s 11-item functional health assessment' and clinical observation, interviews as well as physical examination were used as data collections. Based on results of health assessment as above, the patient’s health problems were identified as the following: impaired skin integrity, chronic pain, and hopeless. Besides to relieve the symptom of pain due to disease or the treatment of hemodialysis and provide wound care, the first author also played a role to assist the patient to achieve his goal of receiving the hospice palliative care. Finally, with much effort of nurses to communicate with medical teams between the surgical and hospice wards, the patient was transferred to the hospice ward to have fulfilled his last wish of having a good death. We hope this nursing experience can be applied to other similar cases in the future.

Keywords: diabetic nephropathy, hospice care, palliative care, spinal cord injury

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7187 The Effects of the Interaction between Prenatal Stress and Diet on Maternal Insulin Resistance and Inflammatory Profile

Authors: Karen L. Lindsay, Sonja Entringer, Claudia Buss, Pathik D. Wadhwa

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Maternal nutrition and stress are independently recognized as among the most important factors that influence prenatal biology, with implications for fetal development and poor pregnancy outcomes. While there is substantial evidence from non-pregnancy human and animal studies that a complex, bi-directional relationship exists between nutrition and stress, to the author’s best knowledge, their interaction in the context of pregnancy has been significantly understudied. The aim of this study is to assess the interaction between maternal psychological stress and diet quality across pregnancy and its effects on biomarkers of prenatal insulin resistance and inflammation. This is a prospective longitudinal study of N=235 women carrying a healthy, singleton pregnancy, recruited from prenatal clinics of the University of California, Irvine Medical Center. Participants completed a 4-day ambulatory assessment in early, middle and late pregnancy, which included multiple daily electronic diary entries using Ecological Momentary Assessment (EMA) technology on a dedicated study smartphone. The EMA diaries gathered moment-level data on maternal perceived stress, negative mood, positive mood and quality of social interactions. The numerical scores for these variables were averaged across each study time-point and converted to Z-scores. A single composite variable for 'STRESS' was computed as follows: (Negative mood+Perceived stress)–(Positive mood+Social interaction quality). Dietary intakes were assessed by three 24-hour dietary recalls conducted within two weeks of each 4-day assessment. Daily nutrient and food group intakes were averaged across each study time-point. The Alternative Healthy Eating Index adapted for pregnancy (AHEI-P) was computed for early, middle and late pregnancy as a validated summary measure of diet quality. At the end of each 4-day ambulatory assessment, women provided a fasting blood sample, which was assayed for levels of glucose, insulin, Interleukin (IL)-6 and Tumor Necrosis Factor (TNF)-α. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) was computed. Pearson’s correlation was used to explore the relationship between maternal STRESS and AHEI-P within and between each study time-point. Linear regression was employed to test the association of the stress-diet interaction (STRESS*AHEI-P) with the biological markers HOMA-IR, IL-6 and TNF-α at each study time-point, adjusting for key covariates (pre-pregnancy body mass index, maternal education level, race/ethnicity). Maternal STRESS and AHEI-P were significantly inversely correlated in early (r=-0.164, p=0.018) and mid-pregnancy (-0.160, p=0.019), and AHEI-P from earlier gestational time-points correlated with later STRESS (early AHEI-P x mid STRESS: r=-0.168, p=0.017; mid AHEI-P x late STRESS: r=-0.142, p=0.041). In regression models, the interaction term was not associated with HOMA-IR or IL-6 at any gestational time-point. The stress-diet interaction term was significantly associated with TNF-α according to the following patterns: early AHEI-P*early STRESS vs early TNF-α (p=0.005); early AHEI-P*early STRESS vs mid TNF-α (p=0.002); early AHEI-P*mid STRESS vs mid TNF-α (p=0.005); mid AHEI-P*mid STRESS vs mid TNF-α (p=0.070); mid AHEI-P*late STRESS vs late TNF-α (p=0.011). Poor diet quality is significantly related to higher psychosocial stress levels in pregnant women across gestation, which may promote inflammation via TNF-α. Future prenatal studies should consider the combined effects of maternal stress and diet when evaluating either one of these factors on pregnancy or infant outcomes.

Keywords: diet quality, inflammation, insulin resistance, nutrition, pregnancy, stress, tumor necrosis factor-alpha

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7186 An Assessment of Inferior Dental (IDN) and Lingual Nerve (LN) Injuries Following Third Molar Removal Under LA, IVS, and GA - An Audit and Case-Series

Authors: Aamna Tufail, Catherine Anyanwu

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Introduction/Aims: Neurosensory deficits following third molar removal affect the quality of life markedly. The purpose of this audit was to evaluate the incidence of IDN and LN damage and to compare departmental rates to an established standard. A secondary objective was to provide a descriptive summary of identified cases for clinical learning. Materials and Methods: A retrospective audit was conducted by a telephone survey of 101 patients who had third molar extractions performed under LA, IVS, or GA from January 2019 to June 2020 at a District General Hospital. The results were compared to a clinical standard identified as Cheng et al1. Data collection included mode of surgery, mode of anaesthesia, grade of clinician, assessment of difficulty, severity, and duration of symptoms. Results/Statistics: A total of 101 patients had 136 third molars extracted. Age range was 18-84 years. 44% extractions were under LA, 52% under GA, and 4% under IV sedation. 30% were simple extractions, 68% were surgical removals, 2% were unspecified. 89% extractions were performed by an Associate Specialist, 5% by a consultant, and 6% by unspecified grade of clinician. The rate of IDN injuries was 2.9% (n=4), higher than standard (0.3%). The rate of LN injuries was 0.7% (n=1), same as standard (0.7%). The 5 cases of neurosensory deficits are discussed in detail. Conclusions/Clinical Relevance: The rate of ID nerve injuries was higher than the standard. The rate of LN complications was lower than the standard.

Keywords: inferior dental nerve, lingual nerve, nerve injuries, third molars

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7185 The African Notion of Moral Personhood

Authors: Meshandren Naidoo

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Personhood is an important philosophical and ethical device that belies many major ethical and legal issues. The concept of African personhood is often overlooked, however, given the decolonization projects occurring in Africa, it is important to consider this view. African personhood, as opposed to Western personhood, is not individualistic in nature. The latter is predominantly Kantian and based on the notion that all persons have equal moral due to their capacity for a reason, whereas communitarianism is central to an African conception of personhood.

Keywords: African philosophy, bioethics, ethics, personhood

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7184 Health Literacy Levels of South African Primary Health Care Patients

Authors: Boitumelo Ditshwane, Zelda Janse van Rensburg, Wanda Jacobs,

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Health literacy is defined as competencies and skills that individuals need to find, comprehend, evaluate, and use to make knowledgeable choices to improve their health and well-being. Low health literacy has been found to affect people’s ability to take care of their own health. Incomprehension of health education and health care instructions due to low health literacy is often due to information given at a level that is above the patient’s level of understanding. The study aimed to test the health literacy levels of South African PHC patients using a previously developed health literacy assessment tool. Determining health literacy levels may assist PHC nurses in providing health education and health care instructions to the patient on the patient’s level of understanding and, therefore, ensuring positive health outcomes for the patient. A health literacy assessment tool, translated into ten official South African languages, was used to quantitatively determine the health literacy levels of 400 PHC patients in five clinics in Gauteng, South Africa. Patients’ health literacy levels were tested in English, and nine other official languages spoken in South Africa and were compared. The results revealed that patients understand information better when given in their preferred language. Giving health education in a language and level that is better understood by the patient may lead to better health outcomes and prevent adverse health. Patients may better understand instructions provided, be more likely to follow the correct route of medication, honor appointments, comply with medication, and thus have better treatment outcomes.

Keywords: health literacy, primary health care, South Africa, patients

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7183 Performance Analysis of Modified Solar Water Heating System for Climatic Condition of Allahabad, India

Authors: Kirti Tewari, Rahul Dev

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Solar water heating is a thermodynamic process of heating water using sunlight with the help of solar water heater. Thus, solar water heater is a device used to harness solar energy. In this paper, a modified solar water heating system (MSWHS) has been proposed over flat plate collector (FPC) and Evacuated tube collector (ETC). The modifications include selection of materials other than glass, and glass wool which are conventionally used for fabricating FPC and ETC. Some modifications in design have also been proposed. Its collector is made of double layer of semi-cylindrical acrylic tubes and fibre reinforced plastic (FRP) insulation base. Water tank is made of double layer of acrylic sheet except base and north wall. FRP is used in base and north wall of the water tank. A concept of equivalent thickness has been utilised for calculating the dimensions of collector plate, acrylic tube and tank. A thermal model for the proposed design of MSWHS is developed and simulation is carried out on MATLAB for the capacity of 200L MSWHS having collector area of 1.6 m2, length of acrylic tubes of 2m at an inclination angle 25° which is taken nearly equal to the latitude of the given location. Latitude of Allahabad is 24.45° N. The results show that the maximum temperature of water in tank and tube has been found to be 71.2°C and 73.3°C at 17:00hr and 16:00hr respectively in March for the climatic data of Allahabad. Theoretical performance analysis has been carried out by varying number of tubes of collector, the tank capacity and climatic data for given months of winter and summer.

Keywords: acrylic, fibre reinforced plastic, solar water heating, thermal model, conventional water heaters

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7182 Multi-Criteria Decision Making Tool for Assessment of Biorefinery Strategies

Authors: Marzouk Benali, Jawad Jeaidi, Behrang Mansoornejad, Olumoye Ajao, Banafsheh Gilani, Nima Ghavidel Mehr

Abstract:

Canadian forest industry is seeking to identify and implement transformational strategies for enhanced financial performance through the emerging bioeconomy or more specifically through the concept of the biorefinery. For example, processing forest residues or surplus of biomass available on the mill sites for the production of biofuels, biochemicals and/or biomaterials is one of the attractive strategies along with traditional wood and paper products and cogenerated energy. There are many possible process-product biorefinery pathways, each associated with specific product portfolios with different levels of risk. Thus, it is not obvious which unique strategy forest industry should select and implement. Therefore, there is a need for analytical and design tools that enable evaluating biorefinery strategies based on a set of criteria considering a perspective of sustainability over the short and long terms, while selecting the existing core products as well as selecting the new product portfolio. In addition, it is critical to assess the manufacturing flexibility to internalize the risk from market price volatility of each targeted bio-based product in the product portfolio, prior to invest heavily in any biorefinery strategy. The proposed paper will focus on introducing a systematic methodology for designing integrated biorefineries using process systems engineering tools as well as a multi-criteria decision making framework to put forward the most effective biorefinery strategies that fulfill the needs of the forest industry. Topics to be covered will include market analysis, techno-economic assessment, cost accounting, energy integration analysis, life cycle assessment and supply chain analysis. This will be followed by describing the vision as well as the key features and functionalities of the I-BIOREF software platform, developed by CanmetENERGY of Natural Resources Canada. Two industrial case studies will be presented to support the robustness and flexibility of I-BIOREF software platform: i) An integrated Canadian Kraft pulp mill with lignin recovery process (namely, LignoBoost™); ii) A standalone biorefinery based on ethanol-organosolv process.

Keywords: biorefinery strategies, bioproducts, co-production, multi-criteria decision making, tool

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7181 High Pressure Thermophysical Properties of Complex Mixtures Relevant to Liquefied Natural Gas (LNG) Processing

Authors: Saif Al Ghafri, Thomas Hughes, Armand Karimi, Kumarini Seneviratne, Jordan Oakley, Michael Johns, Eric F. May

Abstract:

Knowledge of the thermophysical properties of complex mixtures at extreme conditions of pressure and temperature have always been essential to the Liquefied Natural Gas (LNG) industry’s evolution because of the tremendous technical challenges present at all stages in the supply chain from production to liquefaction to transport. Each stage is designed using predictions of the mixture’s properties, such as density, viscosity, surface tension, heat capacity and phase behaviour as a function of temperature, pressure, and composition. Unfortunately, currently available models lead to equipment over-designs of 15% or more. To achieve better designs that work more effectively and/or over a wider range of conditions, new fundamental property data are essential, both to resolve discrepancies in our current predictive capabilities and to extend them to the higher-pressure conditions characteristic of many new gas fields. Furthermore, innovative experimental techniques are required to measure different thermophysical properties at high pressures and over a wide range of temperatures, including near the mixture’s critical points where gas and liquid become indistinguishable and most existing predictive fluid property models used breakdown. In this work, we present a wide range of experimental measurements made for different binary and ternary mixtures relevant to LNG processing, with a particular focus on viscosity, surface tension, heat capacity, bubble-points and density. For this purpose, customized and specialized apparatus were designed and validated over the temperature range (200 to 423) K at pressures to 35 MPa. The mixtures studied were (CH4 + C3H8), (CH4 + C3H8 + CO2) and (CH4 + C3H8 + C7H16); in the last of these the heptane contents was up to 10 mol %. Viscosity was measured using a vibrating wire apparatus, while mixture densities were obtained by means of a high-pressure magnetic-suspension densimeter and an isochoric cell apparatus; the latter was also used to determine bubble-points. Surface tensions were measured using the capillary rise method in a visual cell, which also enabled the location of the mixture critical point to be determined from observations of critical opalescence. Mixture heat capacities were measured using a customised high-pressure differential scanning calorimeter (DSC). The combined standard relative uncertainties were less than 0.3% for density, 2% for viscosity, 3% for heat capacity and 3 % for surface tension. The extensive experimental data gathered in this work were compared with a variety of different advanced engineering models frequently used for predicting thermophysical properties of mixtures relevant to LNG processing. In many cases the discrepancies between the predictions of different engineering models for these mixtures was large, and the high quality data allowed erroneous but often widely-used models to be identified. The data enable the development of new or improved models, to be implemented in process simulation software, so that the fluid properties needed for equipment and process design can be predicted reliably. This in turn will enable reduced capital and operational expenditure by the LNG industry. The current work also aided the community of scientists working to advance theoretical descriptions of fluid properties by allowing to identify deficiencies in theoretical descriptions and calculations.

Keywords: LNG, thermophysical, viscosity, density, surface tension, heat capacity, bubble points, models

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7180 Decentralized Forest Policy for Natural Sal (Shorea robusta) Forests Management in the Terai Region of Nepal

Authors: Medani Prasad Rijal

Abstract:

The study outlines the impacts of decentralized forest policy on natural Sal (shorea robusta) forests in the Terai region of Nepal. The government has implemented community forestry program to manage the forest resources and improve the livelihood of local people collectively. The forest management authorities such as conserve, manage, develop and use of forest resources were shifted to the local communities, however, the ownership right of the forestland retained by the government. Local communities took the decision on harvesting, distribution, and sell of forest products by fixing the prices independently. The local communities were putting the low value of forest products and distributed among the user households on the name of collective decision. The decision of low valuation is devaluating the worth of forest products. Therefore, the study hypothesized that decision-making capacities are equally prominent next to the decentralized policy and program formulation. To accomplish the study, individual to group level discussions and questionnaire survey methods were applied with executive committee members and user households. The study revealed that the local intuition called Community Forest User Group (CFUG) committee normally took the decisions on consensus basis. Considering to the access and affording capacity of user households having poor economic backgrounds, low pricing mechanism of forest products has been practiced, even though the Sal timber is far expensive in the local market. The local communities thought that low pricing mechanism is accessible to all user households from poor to better off households. However, the analysis of forest products distribution opposed the assumption as most of the Sal timber, which is the most valuable forest product of community forest only purchased by the limited households of better economic conditions. Since the Terai region is heterogeneous by socio-economic conditions, better off households always have higher affording capacity and possibility of taking higher timber benefits because of low price mechanism. On the other hand, the minimum price rate of forest products has poor contribution in community fund collection. Consequently, it has poor support to carry out poverty alleviation activities to poor people. The local communities have been fixed Sal timber price rate around three times cheaper than normal market price, which is a strong evidence of forest product devaluation itself. Finally, the study concluded that the capacity building of local executives as the decision-makers of natural Sal forests is equally indispensable next to the policy and program formulation for effective decentralized forest management. Unilateral decentralized forest policy may devaluate the forest products rather than devolve of power to the local communities and empower to them.

Keywords: community forestry program, decentralized forest policy, Nepal, Sal forests, Terai

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7179 Comparative Analysis of the Treatment of Okra Seed and Soy Beans Oil with Crude Enzyme Extract from Malted Rice

Authors: Eduzor Esther, Uhiara Ngozi, Ya’u Abubakar Umar, Anayo Jacob Gabriel, Umar Ahmed

Abstract:

The study investigated the characteristic effect of treating okra seed and soybeans seed oil with crude enzymes extract from malted rice. The oils from okra seeds and soybeans were obtained by solvent extraction method using N-hexane solvent. Soybeans seeds had higher percentage oil yield than okra seed. 250ml of each oil was thoroughly mixed with 5ml of the malted rice extract at 400C for 5mins and then filtered and regarded as treated oil while another batch of 250ml of each oil was not mixed with the malted rice extract and regarded as untreated oil. All the oils were analyzed for specific gravity, refractive index, emulsification capacity, absortivity, TSS and viscosity. Treated okra seed and soybeans oil gave higher values for specific gravity, than the untreated oil for okra seed and soybeans oil respectively. The emulsification capacity values were also higher for treated oils, when compared to the untreated oil, for okra seed and soybeans oil respectively. Treated okra seed and soybeans oil also had higher range of values for absorptivity, than the untreated oil for okra seed and soybeans respectively. The ranges of T.S.S values of the treated oil were also higher, than those of the untreated oil for okra seed and soybeans respectively. The results of viscosity showed that the treated oil had higher values, than the untreated oil for okra seed and soybeans oil respectively. However, the results of refractive index showed that the untreated oils had higher values ranges of than the treated oils for okra seed and soybeans respectively. Treated oil show better quality in respect to the parameters analyst, except the refractive index which is slightly less but also is within the rangiest of standard, the oils are high in unsaturation especially okra oil when compared with soya beans oil. It is recommended that, treated oil of okra seeds and soya beans can serve better than many oils that presently in use such as ground nut oil, palm oil and cotton seeds oil.

Keywords: extract, malted, oil, okra, rice, seed, soybeans

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7178 Post-Anesthetic Recovery: The Best Moment to Apply Positive Pressure in Airway in Postoperative Bariatric Surgery

Authors: Eli Maria Pazzianotto-Forti, Patrícia Brigatto, Letícia Baltieri, Carolina Moraes Da Costa, Maura Rigoldi Simoes Da Rocha, Irineu Rasera Jr

Abstract:

The application of positive pressure in airway can contribute to the restoration of lung volumes, capacities and prevent respiratory complications. The aim was to investigate the use of Bilevel Positive Airway Pressure (BIPAP) in morbidly obese in two moments in postoperative bariatric surgery: In the post-anesthetic recovery (PAR) and on the 1st postoperative day (1stPO). Twenty morbidly obese, aged between 25 and 55 years, underwent pulmonary function test and chest X-ray preoperatively and on the day of discharge (2nd day after surgery). They were randomly allocated in groups. GPAR: received BIPAP treatment in PAR, for an hour and G1stPO: received BIPAP for one hour, on the 1stPO. There were significant reductions in slow vital capacity (SVC) (p=0.0007), inspiratory reserve volume (IRV) (p=0.0016) and forced vital capacity (FVC) (p=0.0013) in the postoperative in GPAR and the expiratory reserve volume (ERV) remained (p=0.4446). In the G1stPO, there were significant reductions for: SVC p=<0.0001, ERV p=0.0191, IRV p= 0.0026 and FVC p=<0.0001. Comparing between groups, the SVC (p=0.0027) and FVC (p=0.0028) showed significant difference between the treatments. However, the GPAR showed fewer declines of these capacities. To the ERV (p= 0.1646) and IRV (p=0.3973) there was no significant difference between groups. The atelectasis prevalence was 10% for the GPAR and 30% for G1stPO, with significant difference between the proportions (p = 0.0027). The lowest reduction in SVC and FVC happens when positive pressure is applied in PAR. Thus, the use of BIPAP in the PAR can promote a restoration of ERV and contribute to the reduction of atelectasis. FAPESP 2013/06334-8.

Keywords: atelectasis, bariatric surgery, physiotherapy, pulmonary function, positive pressure

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7177 Prospective Study of the Evaluation of Autologous Blood Injection in the Treatment of Lateral Epicondylitis

Authors: Bheeshma B., Mathivanan N., Manoj Deepak M., Prabhu Thangaraju, K. Venkatachalam

Abstract:

This study involves the effect of autologous blood injection for patients who had degeneration of the origin of extensor carpi radialis brevis which was confirmed radio logically and by ultrasound examination and failed cortisone injections to the lateral epicondylitis. In this prospective longitudinal series involves pre-injection assessment of grip strength, pain, and function, using the patient-rated tennis elbow evaluation. In this study, blood from the contralateral limb is taken and injected into the affected limb with the help of ultrasound guidance and then the patient wore a customized wrist support for five days, after which they were commenced with stretching, strengthening, and massage programme with an occupational therapist. In these patients assessment was done after six months and then finally at 12 months after injection, using the patient-rated tennis elbow evaluation. 50 patients completed the study, showing significant improvement in pain; the worst pain decreased by two to five points out of a 10-point visual analogue for pain. Self-perceived function improved by 11–25 points out of 100. Women showed significant increase in grip, but men did not. Our study thus concludes that autologous blood injection show significant improvement in pain and function in patients with chronic lateral epicondylitis, who did not have relief with cortisone injection.

Keywords: lateral epicondylitis, autologous blood injection, conservative treatment, plasma-rich proteins (PRPs)

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7176 The Minimum Age of Criminal Responsibility in the Philippines: Balancing International Standards and Domestic Concerns

Authors: Harold P. Pareja

Abstract:

This paper answers the question whether the minimum age of criminal responsibility under the Republic Act No. 9344 (Juvenile Justice Act) as amended by Republic Act No. 10630 should be lowered to 15 years of age or not in the light of international standards and domestic concerns both of which will definitely elicit strong views. It also explores the specific provision on the minimum age of criminal responsibility under the Republic Act No. 9344 (Juvenile Justice Act) and traces the bases of such law by discussing its presented evidences and justifications as reflected in the records of proceedings in the law-making phase. On one hand, the paper discusses the impact of lowering the minimum age to the state of juvenile delinquencies and to the rate of rehabilitation for those CICL who have undergone the DSWD-supervised recovery programs. On the other hand, it presents its impact to the international community specifically to the Committee of the Rights of the Child and the UNICEF considering that the even the current minimum age set in RA 9344 is lower than the international standards. Document review and content analysis are the major research tools. Primary and secondary sources were used as references such as Philippine laws on juvenile justice and from the different states international think-tanks. The absence of reliable evidences on criminal capacity made the arguments in increasing the MACR in the harder position. Studies on criminal capacity vary from different countries and from practitioners in in the fields of psychology, psychiatry and forensics. Juvenile delinquency is mainly contributed by poverty and dysfunctional families. On the other hand, the science of the criminal mind specifically among children has not been established yet. Philippines have the legal obligations to be faithful to the CRC and other related international instruments for the juvenile justice and welfare system. Decreasing MACR does not only send wrong message to the international community but the Philippines is violating its own laws.

Keywords: juvenile justice, minimum age of responsibility (MAR), juvenile justice act of the Philippines, children in conflict with the law, international standards on juvenile justice

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7175 A Study on Earthquake Activities and Tectonic Setting in the Northeastern Part of Egypt

Authors: Sayed Abdallah Mohamed Dahy

Abstract:

Northeastern part of Egypt is considered one of the few regions of the world whereas evidence of historical activities has been documented during the last 48 centuries or more. Instrumental, historical and pre-historical seismicity data indicate that large destructive earthquakes have occurred quite frequently in the investigated area. The main aims in the present study were to redraw attention to the fact that the northeastern part of Egypt is seismically active and this result is associated with earthquake risk in the region. The interaction of the African, Arabian and Eurasian plates and Sinai subplate, is the main factor behind the earthquake activities of northeastern part of Egypt. All earthquakes occur at shallow depth and are concentrated at four seismic zones, these zones including the Gulfs of Suez and Aqaba, around the entrance of the Gulf of Suez and the fourth one is located at the south-west of great Cairo (Dahshour area). The seismicity map of the previous zones shows that the activity is coincide with the major tectonic trends of the Suez rift, Aqaba rift with their connection with the great rift system of the Red Sea and Gulf of Suez-Cairo-Alexandria trend.

Keywords: earthquake ectivities, Egypt, northeastern, tectonic setting

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7174 Effect of Subsequent Drying and Wetting on the Small Strain Shear Modulus of Unsaturated Soils

Authors: A. Khosravi, S. Ghadirian, J. S. McCartney

Abstract:

Evaluation of the seismic-induced settlement of an unsaturated soil layer depends on several variables, among which the small strain shear modulus, Gmax, and soil’s state of stress have been demonstrated to be of particular significance. Recent interpretation of trends in Gmax revealed considerable effects of the degree of saturation and hydraulic hysteresis on the shear stiffness of soils in unsaturated states. Accordingly, the soil layer is expected to experience different settlement behaviors depending on the soil saturation and seasonal weathering conditions. In this study, a semi-empirical formulation was adapted to extend an existing Gmax model to infer hysteretic effects along different paths of the SWRC including scanning curves. The suitability of the proposed approach is validated against experimental results from a suction-controlled resonant column test and from data reported in literature. The model was observed to follow the experimental data along different paths of the SWRC, and showed a slight hysteresis in shear modulus along the scanning curves.

Keywords: hydraulic hysteresis, scanning path, small strain shear modulus, unsaturated soil

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7173 Study of Sustainability Indicators in a Milk Production Process

Authors: E. Lacasa, J. L. Santolaya, I. Millán

Abstract:

The progress toward sustainability implies maintaining and preferably improving both, human and ecosystem well-being, according to a triple bottom line that includes the environmental, economic and social dimensions. The life cycle assessment (LCA) is a method applicable to all production sectors that aims to quantify the environmental pressures and the benefits related to goods and services, as well as the trade-offs and the scope for improving areas of the production process. While using LCA to measure the environmental dimension of sustainability is widespread, similar approaches for the economic and the social dimensions still have limited application worldwide and there is a need for consistent and robust methods and indicators. This paper focuses on the milk production process and presents the analysis of the flows exchanged by an industrial installation through accounting all the energy and material inputs and the associated emissions and waste outputs at this stage of its life cycle. The functional unit is one litre of milk produced. Different metrics and indicators are used to assess the three dimensions of sustainability. Metrics considered useful to assess the production activities are the total water and energy consumptions and the milk production volume of each cow. The global warming, the value added and the working hours are indicators used to measure each sustainability dimension. The study is performed with two types of feeding of the cows, which includes a change in percentages of components as well. Nutritional composition of the milk obtained is almost kept. It is observed that environmental and social improvements involve high economic costs.

Keywords: milk production, sustainability, indicators, life cycle assessment

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7172 Methodological Approach to the Elaboration and Implementation of the Spatial-Urban Plan for the Special Purpose Area: Case-Study of Infrastructure Corridor of Highway E-80, Section Nis-Merdare, Serbia

Authors: Nebojsa Stefanovic, Sasa Milijic, Natasa Danilovic Hristic

Abstract:

Spatial plan of the special purpose area constitutes a basic tool in the planning of infrastructure corridor of a highway. The aim of the plan is to define the planning basis and provision of spatial conditions for the construction and operation of the highway, as well as for developing other infrastructure systems in the corridor. This paper presents a methodology and approach to the preparation of the Spatial Plan for the special purpose area for the infrastructure corridor of the highway E-80, Section Niš-Merdare in Serbia. The applied methodological approach is based on the combined application of the integrative and participatory method in the decision-making process on the sustainable development of the highway corridor. It was found that, for the planning and management of the infrastructure corridor, a key problem is coordination of spatial and urban planning, strategic environmental assessment and sectoral traffic planning and designing. Through the development of the plan, special attention is focused on increasing the accessibility of the local and regional surrounding, reducing the adverse impacts on the development of settlements and the economy, protection of natural resources, natural and cultural heritage, and the development of other infrastructure systems in the corridor of the highway. As a result of the applied methodology, this paper analyzes the basic features such as coverage, the concept, protected zones, service facilities and objects, the rules of development and construction, etc. Special emphasis is placed to methodology and results of the Strategic Environmental Assessment of the Spatial Plan, and to the importance of protection measures, with the special significance of air and noise protection measures. For evaluation in the Strategic Environmental Assessment, a multicriteria expert evaluation (semi-quantitative method) of planned solutions was used in relation to the set of goals and relevant indicators, based on the basic set of indicators of sustainable development. Evaluation of planned solutions encompassed the significance and size, spatial conditions and probability of the impact of planned solutions on the environment, and the defined goals of strategic assessment. The framework of the implementation of the Spatial Plan is presented, which is determined for the simultaneous elaboration of planning solutions at two levels: the strategic level of the spatial plan and detailed urban plan level. It is also analyzed the relationship of the Spatial Plan to other applicable planning documents for the planning area. The effects of this methodological approach relate to enabling integrated planning of the sustainable development of the infrastructure corridor of the highway and its surrounding area, through coordination of spatial, urban and sectoral traffic planning and design, as well as the participation of all key actors in the adoption and implementation of planned decisions. By the conclusions of the paper, it is pointed to the direction for further research, particularly in terms of harmonizing methodology of planning documentation and preparation of technical-design documentation.

Keywords: corridor, environment, highway, impact, methodology, spatial plan, urban

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7171 Continuous-Time Analysis And Performance Assessment For Digital Control Of High-Frequency Switching Synchronous Dc-Dc Converter

Authors: Rihab Hamdi, Amel Hadri Hamida, Ouafae Bennis, Sakina Zerouali

Abstract:

This paper features a performance analysis and robustness assessment of a digitally controlled DC-DC three-cell buck converter associated in parallel, operating in continuous conduction mode (CCM), facing feeding parameters variation and loads disturbance. The control strategy relies on the continuous-time with an averaged modeling technique for high-frequency switching converter. The methodology is to modulate the complete design procedure, in regard to the existence of an instantaneous current operating point for designing the digital closed-loop, to the same continuous-time domain. Moreover, the adopted approach is to include a digital voltage control (DVC) technique, taking an account for digital control delays and sampling effects, which aims at improving efficiency and dynamic response and preventing generally undesired phenomena. The results obtained under load change, input change, and reference change clearly demonstrates an excellent dynamic response of the proposed technique, also as provide stability in any operating conditions, the effectiveness is fast with a smooth tracking of the specified output voltage. Simulations studies in MATLAB/Simulink environment are performed to verify the concept.

Keywords: continuous conduction mode, digital control, parallel multi-cells converter, performance analysis, power electronics

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7170 Environmental Impact of a New-Build Educational Building in England: Life-Cycle Assessment as a Method to Calculate Whole Life Carbon Emissions

Authors: Monkiz Khasreen

Abstract:

In the context of the global trend towards reducing new buildings carbon footprint, the design team is required to make early decisions that have a major influence on embodied and operational carbon. Sustainability strategies should be clear during early stages of building design process, as changes made later can be extremely costly. Life-Cycle Assessment (LCA) could be used as the vehicle to carry other tools and processes towards achieving the requested improvement. Although LCA is the ‘golden standard’ to evaluate buildings from 'cradle to grave', lack of details available on the concept design makes LCA very difficult, if not impossible, to be used as an estimation tool at early stages. Issues related to transparency and accessibility of information in the building industry are affecting the credibility of LCA studies. A verified database derived from LCA case studies is required to be accessible to researchers, design professionals, and decision makers in order to offer guidance on specific areas of significant impact. This database could be the build-up of data from multiple sources within a pool of research held in this context. One of the most important factors that affects the reliability of such data is the temporal factor as building materials, components, and systems are rapidly changing with the advancement of technology making production more efficient and less environmentally harmful. Recent LCA studies on different building functions, types, and structures are always needed to update databases derived from research and to form case bases for comparison studies. There is also a need to make these studies transparent and accessible to designers. The work in this paper sets out to address this need. This paper also presents life-cycle case study of a new-build educational building in England. The building utilised very current construction methods and technologies and is rated as BREEAM excellent. Carbon emissions of different life-cycle stages and different building materials and components were modelled. Scenario and sensitivity analyses were used to estimate the future of new educational buildings in England. The study attempts to form an indicator during the early design stages of similar buildings. Carbon dioxide emissions of this case study building, when normalised according to floor area, lie towards the lower end of the range of worldwide data reported in the literature. Sensitivity analysis shows that life cycle assessment results are highly sensitive to future assumptions made at the design stage, such as future changes in electricity generation structure over time, refurbishment processes and recycling. The analyses also prove that large savings in carbon dioxide emissions can result from very small changes at the design stage.

Keywords: architecture, building, carbon dioxide, construction, educational buildings, England, environmental impact, life-cycle assessment

Procedia PDF Downloads 110