Search results for: low fertility rate
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8175

Search results for: low fertility rate

5415 Effects of Irrigation Applications during Post-Anthesis Period on Flower Development and Pyrethrin Accumulation in Pyrethrum

Authors: Dilnee D. Suraweera, Tim Groom, Brian Chung, Brendan Bond, Andrew Schipp, Marc E. Nicolas

Abstract:

Pyrethrum (Tanacetum cinerariifolium) is a perennial plant belongs to family Asteraceae. This is cultivated commercially for extraction of natural insecticide pyrethrins, which accumulates in their flower head achenes. Approximately 94% of the pyrethrins are produced within secretory ducts and trichomes of achenes of the mature pyrethrum flower. This is the most widely used botanical insecticide in the world and Australia is the current largest pyrethrum producer in the world. Rainfall in pyrethrum growing regions in Australia during pyrethrum flowering period, in late spring and early summer is significantly less. Due to lack of adequate soil moisture and under elevated temperature conditions during post-anthesis period, resulting in yield reductions. Therefore, understanding of yield responses of pyrethrum to irrigation is important for Pyrethrum as a commercial crop. Irrigation management has been identified as a key area of pyrethrum crop management strategies that could be manipulated to increase yield. Pyrethrum is a comparatively drought tolerant plant and it has some ability to survive in dry conditions due to deep rooting. But in dry areas and in dry seasons, the crop cannot reach to its full yield potential without adequate soil moisture. Therefore, irrigation is essential during the flowering period prevent crop water stress and maximise yield. Irrigation during the water deficit period results in an overall increased rate of water uptake and growth by the plant which is essential to achieve the maximum yield benefits from commercial crops. The effects of irrigation treatments applied at post-anthesis period on pyrethrum yield responses were studied in two irrigation methods. This was conducted in a first harvest commercial pyrethrum field in Waubra, Victoria, during 2012/2013 season. Drip irrigation and overhead sprinkler irrigation treatments applied during whole flowering period were compared with ‘rainfed’ treatment in relation to flower yield and pyrethrin yield responses. The results of this experiment showed that the application of 180mm of irrigation throughout the post-anthesis period, from early flowering stages to physiological maturity under drip irrigation treatment increased pyrethrin concentration by 32%, which combined with the 95 % increase in the flower yield to give a total pyrethrin yield increase of 157%, compared to the ‘rainfed’ treatment. In contrast to that overhead sprinkler irrigation treatment increased pyrethrin concentration by 19%, which combined with the 60 % increase in the flower yield to give a total pyrethrin yield increase of 91%, compared to the ‘rainfed’ treatment. Irrigation treatments applied throughout the post-anthesis period significantly increased flower yield as a result of enhancement of number of flowers and flower size. Irrigation provides adequate soil moisture for flower development in pyrethrum which slows the rate of flower development and increases the length of the flowering period, resulting in a delayed crop harvest (11 days) compared to the ‘rainfed’ treatment. Overall, irrigation has a major impact on pyrethrin accumulation which increases the rate and duration of pyrethrin accumulation resulting in higher pyrethrin yield per flower at physiological maturity. The findings of this study will be important for future yield predictions and to develop advanced agronomic strategies to maximise pyrethrin yield in pyrethrum.

Keywords: achene, drip irrigation, overhead irrigation, pyrethrin

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5414 Integrating Technology in Teaching and Learning Mathematics

Authors: Larry Wang

Abstract:

The aim of this paper is to demonstrate how an online homework system is integrated in teaching and learning mathematics and how it improves the student success rates in some gateway mathematics courses. WeBWork provided by the Mathematical Association of America is adopted as the online homework system. During the period of 2010-2015, the system was implemented in classes of precalculus, calculus, probability and statistics, discrete mathematics, linear algebra, and differential equations. As a result, the passing rates of the sections with WeBWork are well above other sections without WeBWork (about 7-10% higher). The paper also shows how the WeBWork system was used.

Keywords: gateway mathematics, online grading, pass rate, WeBWorK

Procedia PDF Downloads 273
5413 3D Structuring of Thin Film Solid State Batteries for High Power Demanding Applications

Authors: Alfonso Sepulveda, Brecht Put, Nouha Labyedh, Philippe M. Vereecken

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High energy and power density are the main requirements of today’s high demanding applications in consumer electronics. Lithium ion batteries (LIB) have the highest energy density of all known systems and are thus the best choice for rechargeable micro-batteries. Liquid electrolyte LIBs present limitations in safety, size and design, thus thin film all-solid state batteries are predominantly considered to overcome these restrictions in small devices. Although planar all-solid state thin film LIBs are at present commercially available they have low capacity (<1mAh/cm2) which limits their application scenario. By using micro-or nanostructured surfaces (i.e. 3D batteries) and appropriate conformal coating technology (i.e. electrochemical deposition, ALD) the capacity can be increased while still keeping a high rate performance. The main challenges in the introduction of solid-state LIBs are low ionic conductance and limited cycle life time due to mechanical stress and shearing interfaces. Novel materials and innovative nanostructures have to be explored in order to overcome these limitations. Thin film 3D compatible materials need to provide with the necessary requirements for functional and viable thin-film stacks. Thin film electrodes offer shorter Li-diffusion paths and high gravimetric and volumetric energy densities which allow them to be used at ultra-fast charging rates while keeping their complete capacities. Thin film electrolytes with intrinsically high ion conductivity (~10-3 S.cm) do exist, but are not electrochemically stable. On the other hand, electronically insulating electrolytes with a large electrochemical window and good chemical stability are known, but typically have intrinsically low ionic conductivities (<10-6 S cm). In addition, there is the need for conformal deposition techniques which can offer pinhole-free coverage over large surface areas with large aspect ratio features for electrode, electrolyte and buffer layers. To tackle the scaling of electrodes and the conformal deposition requirements on future 3D batteries we study LiMn2O4 (LMO) and Li4Ti5O12 (LTO). These materials are among the most interesting electrode candidates for thin film batteries offering low cost, low toxicity, high voltage and high capacity. LMO and LTO are considered 3D compatible materials since they can be prepared through conformal deposition techniques. Here, we show the scaling effects on rate performance and cycle stability of thin film cathode layers of LMO created by RF-sputtering. Planar LMO thin films below 100 nm have been electrochemically characterized. The thinnest films show the highest volumetric capacity and the best cycling stability. The increased stability of the films below 50 nm allows cycling in both the 4 and 3V potential region, resulting in a high volumetric capacity of 1.2Ah/cm3. Also, the creation of LTO anode layers through a post-lithiation process of TiO2 is demonstrated here. Planar LTO thin films below 100 nm have been electrochemically characterized. A 70 nm film retains 85% of its original capacity after 100 (dis)charging cycles at 10C. These layers can be implemented into a high aspect ratio structures. IMEC develops high aspect Si pillars arrays which is the base for the advance of 3D thin film all-solid state batteries of future technologies.

Keywords: Li-ion rechargeable batteries, thin film, nanostructures, rate performance, 3D batteries, all-solid state

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5412 Effects of Organic Amendments on Primary Nutrients (N, P and K) in a Sandy Soil

Authors: Nejib Turki, Karima Kouki Khalfallah

Abstract:

The effect of six treatments of organic amendments were evaluated on a sandy soil in the region of Soukra in Tunisia. T1: cattle manure 55 t.ha-1, T2: commercial compost from Germany to 1 t.ha-1, T3: a mixture of 27.5 t.ha-1 of T1 with 0.5 t. ha-1 of T2, T4: commercial compost from France 2 t.ha-1, T5: a Tunisian commercial compost to 10 t.ha-1 and T0: control without treatment. The nitrogen in the soil increase to 0.029 g.kg-1 of soil treatment for the T1 and 0.021 g. kg-1 of soil treatment for the T3. The highest content of P2O5 has been registered by the T3 treatment that 0.44 g kg-1 soil with respect to the control (T0), which shows a content of 0.36 g.kg-1 soil. The soil was initially characterized by a potassium content of 0.8 g kg-1 soil, K2O exchangeable rate varied between 0.63 g.Kg-1 and 0.71 g.kg-1 soil respectively T2 and T1.

Keywords: compost, organic amendement, Ntot, P2O5, K2O

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5411 Experiments to Study the Vapor Bubble Dynamics in Nucleate Pool Boiling

Authors: Parul Goel, Jyeshtharaj B. Joshi, Arun K. Nayak

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Nucleate boiling is characterized by the nucleation, growth and departure of the tiny individual vapor bubbles that originate in the cavities or imperfections present in the heating surface. It finds a wide range of applications, e.g. in heat exchangers or steam generators, core cooling in power reactors or rockets, cooling of electronic circuits, owing to its highly efficient transfer of large amount of heat flux over small temperature differences. Hence, it is important to be able to predict the rate of heat transfer and the safety limit heat flux (critical heat flux, heat flux higher than this can lead to damage of the heating surface) applicable for any given system. A large number of experimental and analytical works exist in the literature, and are based on the idea that the knowledge of the bubble dynamics on the microscopic scale can lead to the understanding of the full picture of the boiling heat transfer. However, the existing data in the literature are scattered over various sets of conditions and often in disagreement with each other. The correlations obtained from such data are also limited to the range of conditions they were established for and no single correlation is applicable over a wide range of parameters. More recently, a number of researchers have been trying to remove empiricism in the heat transfer models to arrive at more phenomenological models using extensive numerical simulations; these models require state-of-the-art experimental data for a wide range of conditions, first for input and later, for their validation. With this idea in mind, experiments with sub-cooled and saturated demineralized water have been carried out under atmospheric pressure to study the bubble dynamics- growth rate, departure size and frequencies for nucleate pool boiling. A number of heating elements have been used to study the dependence of vapor bubble dynamics on the heater surface finish and heater geometry along with the experimental conditions like the degree of sub-cooling, super heat and the heat flux. An attempt has been made to compare the data obtained with the existing data and the correlations in the literature to generate an exhaustive database for the pool boiling conditions.

Keywords: experiment, boiling, bubbles, bubble dynamics, pool boiling

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5410 Emotional State and Cognitive Workload during a Flight Simulation: Heart Rate Study

Authors: Damien Mouratille, Antonio R. Hidalgo-Muñoz, Nadine Matton, Yves Rouillard, Mickael Causse, Radouane El Yagoubi

Abstract:

Background: The monitoring of the physiological activity related to mental workload (MW) on pilots will be useful to improve aviation safety by anticipating human performance degradation. The electrocardiogram (ECG) can reveal MW fluctuations due to either cognitive workload or/and emotional state since this measure exhibits autonomic nervous system modulations. Arguably, heart rate (HR) is one of its most intuitive and reliable parameters. It would be particularly interesting to analyze the interaction between cognitive requirements and emotion in ecologic sets such as a flight simulator. This study aims to explore by means of HR the relation between cognitive demands and emotional activation. Presumably, the effects of cognition and emotion overloads are not necessarily cumulative. Methodology: Eight healthy volunteers in possession of the Private Pilot License were recruited (male; 20.8±3.2 years). ECG signal was recorded along the whole experiment by placing two electrodes on the clavicle and left pectoral of the participants. The HR was computed within 4 minutes segments. NASA-TLX and Big Five inventories were used to assess subjective workload and to consider the influence of individual personality differences. The experiment consisted in completing two dual-tasks of approximately 30 minutes of duration into a flight simulator AL50. Each dual-task required the simultaneous accomplishment of both a pre-established flight plan and an additional task based on target stimulus discrimination inserted between Air Traffic Control instructions. This secondary task allowed us to vary the cognitive workload from low (LC) to high (HC) levels, by combining auditory and visual numerical stimuli to respond to meeting specific criteria. Regarding emotional condition, the two dual-tasks were designed to assure analogous difficulty in terms of solicited cognitive demands. The former was realized by the pilot alone, i.e. Low Arousal (LA) condition. In contrast, the latter generates a high arousal (HA), since the pilot was supervised by two evaluators, filmed and involved into a mock competition with the rest of the participants. Results: Performance for the secondary task showed significant faster reaction times (RT) for HA compared to LA condition (p=.003). Moreover, faster RT was found for LC compared to HC (p < .001) condition. No interaction was found. Concerning HR measure, despite the lack of main effects an interaction between emotion and cognition is evidenced (p=.028). Post hoc analysis showed smaller HR for HA compared to LA condition only for LC (p=.049). Conclusion. The control of an aircraft is a very complex task including strong cognitive demands and depends on the emotional state of pilots. According to the behavioral data, the experimental set has permitted to generate satisfactorily different emotional and cognitive levels. As suggested by the interaction found in HR measure, these two factors do not seem to have a cumulative impact on the sympathetic nervous system. Apparently, low cognitive workload makes pilots more sensitive to emotional variations. These results hint the independency between data processing and emotional regulation. Further physiological data are necessary to confirm and disentangle this relation. This procedure may be useful for monitoring objectively pilot’s mental workload.

Keywords: cognitive demands, emotion, flight simulator, heart rate, mental workload

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5409 Train-The-Trainer in Neonatal Resuscitation in Rural Uganda: A Model for Sustainability and the Barriers Faced

Authors: Emilia K. H. Danielsson-Waters, Malaz Elsaddig, Kevin Jones

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Unfortunately, it is well known that neonatal deaths are a common and potentially preventable occurrence across the world. Neonatal resuscitation is a simple and inexpensive intervention that can effectively reduce this rate, and can be taught and implemented globally. This project is a follow-on from one in 2012, which found that neonatal resuscitation simulation was valuable for education, but would be better improved by being delivered by local staff. Methods: This study involved auditing the neonatal admission and death records within a rural Ugandan hospital, alongside implementing a Train-The-Trainer teaching scheme to teach Neonatal Resuscitation. One local doctor was trained for simulating neonatal resuscitation, whom subsequently taught an additional 14 staff members in one-afternoon session. Participants were asked to complete questionnaires to assess their knowledge and confidence pre- and post-simulation, and a survey to identify barriers and drivers to simulation. Results: The results found that the neonatal mortality rate in this hospital was 25% between July 2016- July 2017, with birth asphyxia, prematurity and sepsis being the most common causes. Barriers to simulation that were identified predominantly included a lack of time, facilities and opportunity, yet all members stated simulation was beneficial for improving skills and confidence. The simulation session received incredibly positive qualitative feedback, and also a 0.58-point increase in knowledge (p=0.197) and 0.73-point increase in confidence (0.079). Conclusion: This research shows that it is possible to create a teaching scheme in a rural hospital, however, many barriers are in place for its sustainability, and a larger sample size with a more sensitive scale is required to achieve statistical significance. This is undeniably important, because teaching neonatal resuscitation can have a direct impact on neonatal mortality. Subsequently, recommendations include that efforts should be put in place to create a sustainable training scheme, for example, by employing a resuscitation officer. Moreover, neonatal resuscitation teaching should be conducted more frequently in hospitals, and conducted in a wider geographical context, including within the community, in order to achieve its full effect.

Keywords: neonatal resuscitation, sustainable medical education, train-the-trainer, Uganda

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5408 Stability Analysis of SEIR Epidemic Model with Treatment Function

Authors: Sasiporn Rattanasupha, Settapat Chinviriyasit

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The treatment function adopts a continuous and differentiable function which can describe the effect of delayed treatment when the number of infected individuals increases and the medical condition is limited. In this paper, the SEIR epidemic model with treatment function is studied to investigate the dynamics of the model due to the effect of treatment. It is assumed that the treatment rate is proportional to the number of infective patients. The stability of the model is analyzed. The model is simulated to illustrate the analytical results and to investigate the effects of treatment on the spread of infection.

Keywords: basic reproduction number, local stability, SEIR epidemic model, treatment function

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5407 Understanding and Addressing the Tuberculosis Notification Gap in Nepal

Authors: Lok Raj Joshi, Naveen Prakash Shah, Sharad Kumar Sharma, I. Ratna Bhattarai, Rajendra Basnet, Deepak Dahal, Bahagwan Maharjan, Seraphine Kaminsa

Abstract:

Context: Tuberculosis (TB) is a significant health issue in Nepal, a country with a high burden of the disease. Despite efforts to control TB, there is still a gap in the notification of TB cases, which hinders effective control and treatment. This paper aims to address this notification gap and proposes strategies to improve TB control in Nepal. Research Aim: The aim of this research is to understand and address the tuberculosis notification gap in Nepal. The focus is on enhancing the healthcare system, involving the private sector and communities, raising awareness, and addressing social determinants to achieve sustainable TB control. Methodology: The research methodology involved a review of existing epidemiological data and research studies related to TB in Nepal. Additionally, consultation with an expert group from the TB control program in Nepal provided insights into the current state of TB control and challenges in addressing the notification gap. Findings: The findings reveal that only 55% of TB cases were reported in 2022, indicating a significant notification gap. Of the reported cases, only 32% and 19% were referred by the private sector and community, respectively. Furthermore, 20% of diagnosed cases were not treated in the initial phase. The estimated number of cases of multidrug-resistant TB (MDR TB) was 2,800, suggesting a low diagnosis rate. Among the diagnosed MDR TB cases, only 60% were receiving treatment. Additionally, it was observed that 20% of diagnosed MDR TB cases were from India and not enrolling in TB treatment in Nepal, indicating a high rate of defaulters. Theoretical Importance: The study highlights the importance of adopting a holistic strategy to address the notification gap in TB cases in Nepal. It emphasizes the need to enhance healthcare infrastructure, raise awareness, involve the private sector and local communities, establish effective methods to trace initial defaulters, implement TB interventions in border regions, and mitigate the social stigma associated with the disease. Data Collection and Analysis Procedures: Data for this study was collected through a review of existing epidemiological data and research studies. The data were then analyzed to identify patterns, trends, and gaps in TB case notification in Nepal.

Keywords: TB, tuberculosis, private sector, community, migrants, nepal

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5406 STC Parameters versus Real Time Measured Parameters to Determine Cost Effectiveness of PV Panels

Authors: V. E. Selaule, R. M. Schoeman H. C. Z. Pienaar

Abstract:

Research has shown that solar energy is a renewable energy resource with the most potential when compared to other renewable energy resources in South Africa. There are many makes of Photovoltaic (PV) panels on the market and it is difficult to assess which to use. PV panel manufacturers use Standard Test Conditions (STC) to rate their PV panels. STC conditions are different from the actual operating environmental conditions were the PV panels are used. This paper describes a practical method to determine the most cost effective available PV panel. The method shows that PV panel manufacturer STC ratings cannot be used to select a cost effective PV panel.

Keywords: PV orientation, PV panel, PV STC, Solar energy

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5405 Placement of Inflow Control Valve for Horizontal Oil Well

Authors: S. Thanabanjerdsin, F. Srisuriyachai, J. Chewaroungroj

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Drilling horizontal well is one of the most cost-effective method to exploit reservoir by increasing exposure area between well and formation. Together with horizontal well technology, intelligent completion is often co-utilized to increases petroleum production by monitoring/control downhole production. Combination of both technological results in an opportunity to lower water cresting phenomenon, a detrimental problem that does not lower only oil recovery but also cause environmental problem due to water disposal. Flow of reservoir fluid is a result from difference between reservoir and wellbore pressure. In horizontal well, reservoir fluid around the heel location enters wellbore at higher rate compared to the toe location. As a consequence, Oil-Water Contact (OWC) at the heel side of moves upward relatively faster compared to the toe side. This causes the well to encounter an early water encroachment problem. Installation of Inflow Control Valve (ICV) in particular sections of horizontal well can involve several parameters such as number of ICV, water cut constrain of each valve, length of each section. This study is mainly focused on optimization of ICV configuration to minimize water production and at the same time, to enhance oil production. A reservoir model consisting of high aspect ratio of oil bearing zone to underneath aquifer is drilled with horizontal well and completed with variation of ICV segments. Optimization of the horizontal well configuration is firstly performed by varying number of ICV, segment length, and individual preset water cut for each segment. Simulation results show that installing ICV can increase oil recovery factor up to 5% of Original Oil In Place (OOIP) and can reduce of produced water depending on ICV segment length as well as ICV parameters. For equally partitioned-ICV segment, more number of segment results in better oil recovery. However, number of segment exceeding 10 may not give a significant additional recovery. In first production period, deformation of OWC strongly depends on number of segment along the well. Higher number of segment results in smoother deformation of OWC. After water breakthrough at heel location segment, the second production period begins. Deformation of OWC is principally dominated by ICV parameters. In certain situations that OWC is unstable such as high production rate, high viscosity fluid above aquifer and strong aquifer, second production period may give wide enough window to ICV parameter to take the roll.

Keywords: horizontal well, water cresting, inflow control valve, reservoir simulation

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5404 Improvement of Reaction Technology of Decalin Halogenation

Authors: Dmitriy Yu. Korulkin, Ravshan M. Nuraliev, Raissa A. Muzychkina

Abstract:

In this research paper, we investigated the main regularities of a radical bromination reaction of decalin. We studied the temperature effect, durations of reaction, frequency rate of process, ratio of initial components, type and number of the initiator on decalin bromination degree. We found specified optimum conditions of synthesis of a perbromodecalin by the method of a decalin bromination. We developed the technological flowchart of receiving a perbromodecalin and the mass balance of process on the first and the subsequent loadings of components. The results of the research of antibacterial and antifungal activity of synthesized bromoderivatives have been represented.

Keywords: decalin, optimum technology, perbromodecalin, radical bromination

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5403 Effect of Bilateral and Unilateral Castration on Feed Utilization and Carcass Characteristics of Growers Rabbit (Orytolagus cunniculus)

Authors: A. H. Dikko, D. N Tsado, M. S. T. Rita, D. S. Umar

Abstract:

This study was conducted on eighteen (18) New Zealand and chinchilla breeds of rabbits were used. The rabbits were allotted to 3 treatments with each treatment having six (6) animals with two (2) replicates. T1 were castrated, which both testes was removed (Bilateral); T2 were castrated, which only one testes was removed (unilateral) and T3 were not castrated (control). In nutrient digestibility, T1 and T2 (p>0.05) has a higher rate than T3. There was no significant (p<0.05) difference in live weight and dressing weight among the treatment groups. There is a significant (p > 0.05) difference in visceral organs in the treatment groups.

Keywords: New Zealand, chinchilla, castration, bilateral, unilateral

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5402 Fruit of the General Status of Usak Provicce District of Sivasli

Authors: Ayşen Melda Çolak, Volkan Okatan, Ercan Yıldız

Abstract:

In our country, fruit production was determined as 17.2 million tons in 2011 according to official data. Turkey fig, apricot, cherry and quince production ranks first in the world. Almost all the regions of our country, despite the growing of fruit 54% of the total fruit production occur in the Mediterranean and the Aegean Region. However, fruit production in the country is consumed in the domestic market and export rates are often very low. In this study, a questionnaire to 100 farmers face-to-face interview. According to the survey, 40% of those in fruit and 7 da of 7 hectares land are small. 30% of soil testing for manufacturers, testing for 20% of the water. Manufacturers who deliberately fertilization rate of only 10%.

Keywords: fruit, generation, potential, Sivasli survey

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5401 A Comparative Study on the Positive and Negative of Electronic Word-of-Mouth on the SERVQUAL Scale-Take A Certain Armed Forces General Hospital in Taiwan As An Example

Authors: Po-Chun Lee, Li-Lin Liang, Ching-Yuan Huang

Abstract:

Purpose: Research on electronic word-of-mouth (eWOM)& online review has been widely used in service industry management research in recent years. The SERVQUAL scale is the most commonly used method to measure service quality. Therefore, the purpose of this research is to combine electronic word of mouth & online review with the SERVQUAL scale. To explore the comparative study of positive and negative electronic word-of-mouth reviews of a certain armed force general hospital in Taiwan. Data sources: This research obtained online word-of-mouth comment data on google maps from a military hospital in Taiwan in the past ten years through Internet data mining technology. Research methods: This study uses the semantic content analysis method to classify word-of-mouth reviews according to the revised PZB SERVQUAL scale. Then carry out statistical analysis. Results of data synthesis: The results of this study disclosed that the negative reviews of this military hospital in Taiwan have been increasing year by year. Under the COVID-19 epidemic, positive word-of-mouth has a downward trend. Among the five determiners of SERVQUAL of PZB, positive word-of-mouth reviews performed best in “Assurance,” with a positive review rate of 58.89%, Followed by 43.33% of “Responsiveness.” In negative word-of-mouth reviews, “Assurance” performed the worst, with a positive rate of 70.99%, followed by responsive 29.01%. Conclusions: The important conclusions of this study disclosed that the total number of electronic word-of-mouth reviews of the military hospital has revealed positive growth in recent years, and the positive word-of-mouth growth has revealed negative growth after the epidemic of COVID-19, while the negative word-of-mouth has grown substantially. Regardless of the positive and negative comments, what patients care most about is “Assurance” of the professional attitude and skills of the medical staff, which needs to be strengthened most urgently. In addition, good “Reliability” will help build positive word-of-mouth. However, poor “Responsiveness” can easily lead to the spread of negative word-of-mouth. This study suggests that the hospital should focus on these few service-oriented quality management and audits.

Keywords: quality of medical service, electronic word-of-mouth, armed forces general hospital

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5400 Simultaneous Determination of Cefazolin and Cefotaxime in Urine by HPLC

Authors: Rafika Bibi, Khaled Khaladi, Hind Mokran, Mohamed Salah Boukhechem

Abstract:

A high performance liquid chromatographic method with ultraviolet detection at 264nm was developed and validate for quantitative determination and separation of cefazolin and cefotaxime in urine, the mobile phase consisted of acetonitrile and phosphate buffer pH4,2(15 :85) (v/v) pumped through ODB 250× 4,6 mm, 5um column at a flow rate of 1ml/min, loop of 20ul. In this condition, the validation of this technique showed that it is linear in a range of 0,01 to 10ug/ml with a good correlation coefficient ( R>0,9997), retention time of cefotaxime, cefazolin was 9.0, 10.1 respectively, the statistical evaluation of the method was examined by means of within day (n=6) and day to day (n=5) and was found to be satisfactory with high accuracy and precision.

Keywords: cefazolin, cefotaxime, HPLC, bioscience, biochemistry, pharmaceutical

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5399 Postoperative Wound Infections Following Caesarean Section in Obese Patients

Authors: S. Yeo, M. Mathur

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Introduction: Obesity, defined as a Body Mass Index (BMI) of more than or equal to 30kg/m, is associated with an increased risk of complications during pregnancy and delivery. During labour, obese mothers often require greater intervention and have higher rates of caesarean section. Despite a low overall rate of serious complications following caesarean section, a high BMI predisposes to a higher risk of postoperative complications. Our study, therefore, aimed to investigate the impact of antenatal obesity on adverse outcomes following caesarean section, particularly wound-related infections. Materials and Methods: A retrospective cohort study of all caesarean deliveries during the first quarter of a chosen year was undertaken in our hospital, which is a tertiary referral centre with > 12,000 deliveries per year. Patients’ health records and data from our hospital’s electronic labour and delivery database were reviewed. Data analysis was performed using the Statistical Package for the Social Sciences (SPSS), and odds ratios plus adjusted odd ratios were calculated with 95% confidence intervals (CI). Results: A total of 1829 deliveries were reviewed during our study period. Of these, 180 (9.8%) patients were obese. The rate of caesarean delivery was 48.9% in obese patients versus 28.1% in non-obese patients. Post-operatively, 17% of obese patients experienced wound infection versus 0.2% of non-obese patients. Obese patients were also more likely to experience major postpartum haemorrhage (4.6% vs. 0.2%) and postpartum pyrexia (18.2% vs. 5.0%) in comparison to non-obese patients. Conclusions: Obesity is a significant risk factor in the development of postoperative complications following caesarean section. Wound infection remains a major concern for obese patients undergoing major surgery and results in extensive morbidity during the postnatal period. Postpartum infection can prolong recovery and affect maternal mental health, leading to reduced perinatal bonding with long-term implications on breastfeeding and parenting confidence. This study supports the need for the development of standardized protocols specifically for obese patients undergoing caesarean section. Multidisciplinary team care, in conjunction with anaesthesia, family physicians, and plastic surgery counterparts, early on in the antenatal journey, may be beneficial where wound complications are anticipated and to minimize the burden of postoperative infection in obese mothers.

Keywords: pregnancy, obesity, caesarean, infection

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5398 Assessment of Potential Chemical Exposure to Betamethasone Valerate and Clobetasol Propionate in Pharmaceutical Manufacturing Laboratories

Authors: Nadeen Felemban, Hamsa Banjer, Rabaah Jaafari

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One of the most common hazards in the pharmaceutical industry is the chemical hazard, which can cause harm or develop occupational health diseases/illnesses due to chronic exposures to hazardous substances. Therefore, a chemical agent management system is required, including hazard identification, risk assessment, controls for specific hazards and inspections, to keep your workplace healthy and safe. However, routine management monitoring is also required to verify the effectiveness of the control measures. Moreover, Betamethasone Valerate and Clobetasol Propionate are some of the APIs (Active Pharmaceutical Ingredients) with highly hazardous classification-Occupational Hazard Category (OHC 4), which requires a full containment (ECA-D) during handling to avoid chemical exposure. According to Safety Data Sheet, those chemicals are reproductive toxicants (reprotoxicant H360D), which may affect female workers’ health and cause fatal damage to an unborn child, or impair fertility. In this study, qualitative (chemical Risk assessment-qCRA) was conducted to assess the chemical exposure during handling of Betamethasone Valerate and Clobetasol Propionate in pharmaceutical laboratories. The outcomes of qCRA identified that there is a risk of potential chemical exposure (risk rating 8 Amber risk). Therefore, immediate actions were taken to ensure interim controls (according to the Hierarchy of controls) are in place and in use to minimize the risk of chemical exposure. No open handlings should be done out of the Steroid Glove Box Isolator (SGB) with the required Personal Protective Equipment (PPEs). The PPEs include coverall, nitrile hand gloves, safety shoes and powered air-purifying respirators (PAPR). Furthermore, a quantitative assessment (personal air sampling) was conducted to verify the effectiveness of the engineering controls (SGB Isolator) and to confirm if there is chemical exposure, as indicated earlier by qCRA. Three personal air samples were collected using an air sampling pump and filter (IOM2 filters, 25mm glass fiber media). The collected samples were analyzed by HPLC in the BV lab, and the measured concentrations were reported in (ug/m3) with reference to Occupation Exposure Limits, 8hr OELs (8hr TWA) for each analytic. The analytical results are needed in 8hr TWA (8hr Time-weighted Average) to be analyzed using Bayesian statistics (IHDataAnalyst). The results of the Bayesian Likelihood Graph indicate (category 0), which means Exposures are de "minimus," trivial, or non-existent Employees have little to no exposure. Also, these results indicate that the 3 samplings are representative samplings with very low variations (SD=0.0014). In conclusion, the engineering controls were effective in protecting the operators from such exposure. However, routine chemical monitoring is required every 3 years unless there is a change in the processor type of chemicals. Also, frequent management monitoring (daily, weekly, and monthly) is required to ensure the control measures are in place and in use. Furthermore, a Similar Exposure Group (SEG) was identified in this activity and included in the annual health surveillance for health monitoring.

Keywords: occupational health and safety, risk assessment, chemical exposure, hierarchy of control, reproductive

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5397 Malaria Outbreak Facilitated by Appearance of Vector-Breeding Sites after Heavy Rainfall and Inadequate Preventive Measures: Nwoya District, Uganda, March–May 2018

Authors: Godfrey Nsereko, Daniel Kadobera, Denis Okethwangu, Joyce Nguna, Alex Riolexus Ario

Abstract:

Background: Malaria is a leading cause of morbidity and mortality in Uganda. In April 2018, malaria cases surged in Nwoya District, northern Uganda, exceeding the action thresholds. We investigated to assess the outbreak’s magnitude, identify transmission risk factors, and recommend evidence-based control measures. Methods: We defined a malaria case as onset of fever in a resident of Nwoya District with a positive Rapid Diagnostic Test or microscopy for malaria P. falciparum from 1 February to 22 May 2018. We reviewed medical records in all health facilities of affected sub-counties to find cases. In a case-control study, we compared exposure risk factors between 107 case-persons and 107 asymptomatic controls matched by age and village. We conducted entomological assessment on vector-density and behavior. Results: We identified 3,879 case-persons (attack rate [AR]=6.5%) and 2 deaths (case-fatality rate=5.2/10,000). Females (AR=8.1%) were more affected than males (AR=4.7%). Of all age groups, the 5-18 year age group (AR=8.4%) was most affected. Heavy rain started on 4 March; a propagated outbreak began during the week of 2 April. In the case-control study, 55% (59/107) of case-patients and 18% (19/107) of controls had stagnant water around households for several days following rainfall (ORM-H=5.6, 95%CI=3.0-11); 25% (27/107) of case-patients and 51% (55/107) of controls wore long-sleeve cloths during evening hours (ORM-H=0.30, 95%CI=0.20-0.60); 29% (31/107) of case-patients and 15% (16/107) of controls did not sleep under a long-lasting insecticide-treated net (LLIN) (ORM-H=2.3, 95%CI=1.1-4.9); 37% (40/107) of case-patients and 52% (56/107) of controls had ≥1 LLIN per 2 household members (ORM-H=0.54, 95%CI=0.30-0.97). Entomological assessment indicated active breeding sites; Anopheles gambiae sensu lato species were the predominant vector. Conclusion: Increased vector breeding sites after heavy rainfall, together with inadequate malaria preventive measures caused this outbreak. We recommended increasing coverage for LLINs and larviciding breeding sites.

Keywords: malaria outbreak, Plasmodium falciparum, global health security, Uganda

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5396 Understanding the Genetic Basis of SUDEP

Authors: Kumar Ashwini, Nayak C. Vinod

Abstract:

Sudden unexpected death in epilepsy (SUDEP) is a rarity. Each year, about one in 150 epileptics, whose seizures are not controlled, may die of SUDEP. It is a leading cause of death in young adults with uncontrolled seizures. Understanding the genetic basis for SUDEP, is crucial given that the rate of sudden death in epilepsy patients is 20 fold that of the general population. We encountered one such case of a young male, a known epileptic, who was brought dead after a sudden collapse. We hereby present a poster discussing the autopsy findings of this case and also highlighting the importance of understanding the genetic basis of SUDEP.

Keywords: sudden death, epilepsy, genetic, autopsy

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5395 Improvements in OpenCV's Viola Jones Algorithm in Face Detection–Skin Detection

Authors: Jyoti Bharti, M. K. Gupta, Astha Jain

Abstract:

This paper proposes a new improved approach for false positives filtering of detected face images on OpenCV’s Viola Jones Algorithm In this approach, for Filtering of False Positives, Skin Detection in two colour spaces i.e. HSV (Hue, Saturation and Value) and YCrCb (Y is luma component and Cr- red difference, Cb- Blue difference) is used. As a result, it is found that false detection has been reduced. Our proposed method reaches the accuracy of about 98.7%. Thus, a better recognition rate is achieved.

Keywords: face detection, Viola Jones, false positives, OpenCV

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5394 Simultaneous Electrochemical Detection of Chromium(III), Arsenic(III), and Mercury (II) In Water Using Anodic Stripping Voltammetry

Authors: V. Sai Geethika, Sai Snehitha Yadavalli, Swati Ghosh Acharyya

Abstract:

This study involves a single element and simultaneous electrochemical detection of heavy metal ions through square wave anodic stripping voltammetry. A glassy carbon electrode was used to detect and quantify heavy metals such as As(III), Hg(II), Cr(VI) ions in water. Under optimized conditions, peak separation was obtained by varying concentrations, scan rates, and temperatures. As (III), Hg (II), Cr (III) were simultaneously detected with GCE. Several analytical methods, such as inductively coupled plasma mass spectroscopy (ICP-MS), atomic absorption spectroscopy (AAS), were used previously to detect heavy metal ions, which are authentic but are not good enough for online monitoring due to the bulkiness of the equipment. The study provides a good alternative that is simple, more efficient, and low-cost, involving a portable potentiostat. Heavy metals having different oxidation states can be detected by anodic stripping voltammetry. This method can be easily integrated with electronics. Square wave Anodic stripping voltammetry is used with a potential range of -2.5 V – 2.5 V for single ion detection by a three-electrode cell consisting of silver/silver chloride(Ag/AgCl) as reference and platinum (Pt) counter and glassy carbon (GCE) working electrodes. All three ions are optimized by varying the parameters like concentration, scan rate, pH, temperature, and all these optimized parameters were used for studying the effects of simultaneous detection. The procedure involves preparing an electrolyte using deionized water, cleaning the surface of GCE, depositing the ions by applying the redox potentials obtained from cyclic voltammetry (CV), and then detecting by applying oxidizing potential, i.e., stripping voltage. So this includes ASV techniques such as open-circuit voltage (OCV), chronoamperometry (CA), and square wave voltammetry (SWV). Firstly, the concentration of the ions varied from 50 ppb to 5000 ppb, and an optimum concentration was determined where the three ions were detected. A concentration of 400 ppb was used while varying the temperatures in the range of 25°C – 45°C. Optimum peak intensity was obtained at a temperature of 30°C with a low scan rate of 0.005 V-s⁻¹. All the parameters were optimized, and several effects have been noticed while three ions As(II), Cr(III), Hg(II) were detected alone and simultaneously.

Keywords: Arsenic(III), Chromium(III), glassy carbon electrode, Mercury (II), square wave anodic stripping voltammetry

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5393 Assessment of Interior Environmental Quality and Airborne Infectious Risk in a Commuter Bus Cabin by Using Computational Fluid Dynamics with Computer Simulated Person

Authors: Yutaro Kyuma, Sung-Jun Yoo, Kazuhide Ito

Abstract:

A commuter bus remains important as a means to network public transportation between railway stations and terminals within cities. In some cases, the boarding time becomes longer, and the boarding rate tends to be higher corresponding to the development of urban cities. The interior environmental quality, e.g. temperature and air quality, in a commuter bus is relatively heterogeneous and complex compared to that of an indoor environment in buildings due to several factors: solar radiative heat – which comes from large-area windows –, inadequate ventilation rate caused by high density of commuters, and metabolic heat generation from travelers themselves. In addition to this, under conditions where many passengers ride in the enclosed space, contact and airborne infectious risk have attracted considerable attention in terms of public health. From this point of view, it is essential to develop the prediction method for assessment of interior environmental quality and infection risk in commuter bus cabins. In this study, we developed a numerical commuter bus model integrated with computer simulated persons to reproduce realistic indoor environment conditions with high occupancy during commuting. Here, computer simulated persons were newly designed considering different types of geometries, e.g., standing position, seating position, and individual differences. Here we conducted coupled computational fluid dynamics (CFD) analysis with radiative heat transfer analysis under steady state condition. Distributions of heterogeneous air flow patterns, temperature, and moisture surrounding the human body under some different ventilation system were analyzed by using CFD technique, and skin surface temperature distributions were analyzed using thermoregulation model that integrated into computer simulated person. Through these analyses, we discussed the interior environmental quality in specific commuter bus cabins. Further, inhaled air quality of each passenger was also analyzed. This study may have possibility to design the ventilation system in bus for improving thermal comfort of occupants.

Keywords: computational fluid dynamics, CFD, computer simulated person, CSP, contaminant, indoor environment, public health, ventilation

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5392 Burnishing Effect on the Mechanical Characteristics of 100C6

Authors: Ouahiba Taamallah, Tarek Litim

Abstract:

This work relates to the physico-geometrical aspect of the surface layers of 100C6 steel having undergone the burnishing treatment by hard steel ball. The application of tip diamond burnishing promotes better roughness compared to turning. In addition, it allows the surface layers to be consolidated by work hardening phenomena. The optimal effects are closely related to the parameters of the treatment and the active part of the device. With an 80% improvement in roughness resulting from the treatment, burnishing can be defined as a finishing operation within the machining range. With a 40% gain in consolidation rate, this treatment is an efficient process for material consolidation.

Keywords: 100C6 steel, burnishing, hardening, roughness

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5391 In-situ and Laboratory Characterization of Fiji Lateritic Soils

Authors: Faijal Ali, Darga Kumar N., Ravikant Singh, Rajnil Lal

Abstract:

Fiji has three major landforms such as plains, low mountains, and hills. The low land soils are formed on beach sand. Fiji soils contain high concentration of iron (III), aluminum oxides and hydroxides. The soil possesses reddish or yellowish colour. The characterization of lateritic soils collected from different locations along the national highway in Viti Levu, Fiji Islands. The research has been carried out mainly to understand the physical and strength properties to assess their suitability for the highway and building construction. In this paper, the field tests such as dynamic cone penetrometer test, field vane shear, field density and laboratory tests such as unconfined compression stress, compaction, grain size analysis and Atterberg limits are conducted. The test results are analyzed and presented. From the results, it is revealed that the soils are having more percentage of silt and clay which is more than 80% and 5 to 15% of fine to medium sand is noticed. The dynamic cone penetrometer results up to 3m depth had similar penetration resistance. For the first 1m depth, the rate of penetration is found 300mm per 3 to 4 blows. In all the sites it is further noticed that the rate of penetration at depths beyond 1.5 m is decreasing for the same number of blows as compared to the top soil. From the penetration resistance measured through dynamic cone penetrometer test, the California bearing ratio and allowable bearing capacities are 4 to 5% and 50 to 100 kPa for the top 1m layer and below 1m these values are increasing. The California bearing ratio of these soils for below 1m depth is in the order of 10% to 20%. The safe bearing capacity of these soils below 1m and up to 3m depth is varying from 150 kPa to 250 kPa. The field vane shear was measured within a depth of 1m from the surface and the values were almost similar varying from 60 kPa to 120 kPa. The liquid limit and plastic limits of these soils are in the range of 40 to 60% and 20 to 25%. Overall it is found that the top 1m soil along the national highway in majority places possess a soft to medium stiff behavior with low to medium bearing capacity as well low California bearing ratio values. It is recommended to ascertain these soils behavior in terms of geotechnical parameters before taking up any construction activity.

Keywords: California bearing ratio, dynamic cone penetrometer test, field vane shear, unconfined compression stress.

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5390 Quality of Life after Damage Control Laparotomy for Trauma

Authors: Noman Shahzad, Amyn Pardhan, Hasnain Zafar

Abstract:

Introduction: Though short term survival advantage of damage control laparotomy in management of critically ill trauma patients is established, there is little known about the long-term quality of life of these patients. Facial closure rate after damage control laparotomy is reported to be 20-70 percent. Abdominal wall reconstruction in those who failed to achieve facial closure is challenging and can potentially affect quality of life of these patients. Methodology: We conducted retrospective matched cohort study. Adult patients who underwent damage control laparotomy from Jan 2007 till Jun 2013 were identified through medical record. Patients who had concomitant disabling brain injury or limb injuries requiring amputation were excluded. Age, gender and presentation time matched non exposure group of patients who underwent laparotomy for trauma but no damage control were identified for each damage control laparotomy patient. Quality of life assessment was done via telephonic interview at least one year after the operation, using Urdu version of EuroQol Group Quality of Life (QOL) questionnaire EQ5D after permission. Wilcoxon signed rank test was used to compare QOL scores and McNemar test was used to compare individual parameters of QOL questionnaire. Study was approved by institutional ethical review committee. Results: Out of 32 patients who underwent damage control laparotomy during study period, 20 fulfilled the selection criteria for which 20 matched controls were selected. Median age of patients (IQ Range) was 33 (26-40) years. Facial closure rate in damage control laparotomy group was 40% (8/20). One third of those who did not achieve facial closure (4/12) underwent abdominal wall reconstruction. Self-reported QOL score of damage control laparotomy patients was significantly worse than non-damage control group (p = 0.032). There was no statistically significant difference in two groups regarding individual QOL measures. Significantly, more patients in damage control group were requiring use of abdominal binder, and more patients in damage control group had to either change their job or had limitations in continuing previous job. Our study was not adequately powered to detect factors responsible for worse QOL in damage control group. Conclusion: Quality of life of damage control patients is worse than their age and gender matched patients who underwent trauma laparotomy but not damage control. Adequately powered studies need to be conducted to explore factors responsible for this finding for potential improvement.

Keywords: damage control laparotomy, laparostomy, quality of life

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5389 FPGA Implementation of the BB84 Protocol

Authors: Jaouadi Ikram, Machhout Mohsen

Abstract:

The development of a quantum key distribution (QKD) system on a field-programmable gate array (FPGA) platform is the subject of this paper. A quantum cryptographic protocol is designed based on the properties of quantum information and the characteristics of FPGAs. The proposed protocol performs key extraction, reconciliation, error correction, and privacy amplification tasks to generate a perfectly secret final key. We modeled the presence of the spy in our system with a strategy to reveal some of the exchanged information without being noticed. Using an FPGA card with a 100 MHz clock frequency, we have demonstrated the evolution of the error rate as well as the amounts of mutual information (between the two interlocutors and that of the spy) passing from one step to another in the key generation process.

Keywords: QKD, BB84, protocol, cryptography, FPGA, key, security, communication

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5388 How Does Ethics Impact Marketing Decision Making of a Company: An Evidence from the Telecommunication Sector of Pakistan

Authors: Mohammad Daud Ali

Abstract:

For the past decade, marketing ethics has been a central point for academic researchers and practitioners. In particular, the development of frameworks and models to help in the analysis of marketing decisions are the focus of research. The current study aims at finding whether ethical decisions (honesty, fairness, responsibility, and respect) affect organizational marketing decisions. A selection of 250 respondents was purposely made from the telecommunication industry of Pakistan, out of which 204 responses were induced at an acceptable rate of 81.6%. A five-point Likert Scale, itemized with 12 items, was adopted from Taylor-Dunlop & Lester (2000) and used to draw responses regarding ethics.

Keywords: marketing, ethics, decisions making, telecommunication, Pakistan

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5387 Specification Requirements for a Combined Dehumidifier/Cooling Panel: A Global Scale Analysis

Authors: Damien Gondre, Hatem Ben Maad, Abdelkrim Trabelsi, Frédéric Kuznik, Joseph Virgone

Abstract:

The use of a radiant cooling solution would enable to lower cooling needs which is of great interest when the demand is initially high (hot climate). But, radiant systems are not naturally compatibles with humid climates since a low-temperature surface leads to condensation risks as soon as the surface temperature is close to or lower than the dew point temperature. A radiant cooling system combined to a dehumidification system would enable to remove humidity for the space, thereby lowering the dew point temperature. The humidity removal needs to be especially effective near the cooled surface. This requirement could be fulfilled by a system using a single desiccant fluid for the removal of both excessive heat and moisture. This task aims at providing an estimation of the specification requirements of such system in terms of cooling power and dehumidification rate required to fulfill comfort issues and to prevent any condensation risk on the cool panel surface. The present paper develops a preliminary study on the specification requirements, performances and behavior of a combined dehumidifier/cooling ceiling panel for different operating conditions. This study has been carried using the TRNSYS software which allows nodal calculations of thermal systems. It consists of the dynamic modeling of heat and vapor balances of a 5m x 3m x 2.7m office space. In a first design estimation, this room is equipped with an ideal heating, cooling, humidification and dehumidification system so that the room temperature is always maintained in between 21C and 25C with a relative humidity in between 40% and 60%. The room is also equipped with a ventilation system that includes a heat recovery heat exchanger and another heat exchanger connected to a heat sink. Main results show that the system should be designed to meet a cooling power of 42W.m−2 and a desiccant rate of 45 gH2O.h−1. In a second time, a parametric study of comfort issues and system performances has been achieved on a more realistic system (that includes a chilled ceiling) under different operating conditions. It enables an estimation of an acceptable range of operating conditions. This preliminary study is intended to provide useful information for the system design.

Keywords: dehumidification, nodal calculation, radiant cooling panel, system sizing

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5386 Different Stages for the Creation of Electric Arc Plasma through Slow Rate Current Injection to Single Exploding Wire, by Simulation and Experiment

Authors: Ali Kadivar, Kaveh Niayesh

Abstract:

This work simulates the voltage drop and resistance of the explosion of copper wires of diameters 25, 40, and 100 µm surrounded by 1 bar nitrogen exposed to a 150 A current and before plasma formation. The absorption of electrical energy in an exploding wire is greatly diminished when the plasma is formed. This study shows the importance of considering radiation and heat conductivity in the accuracy of the circuit simulations. The radiation of the dense plasma formed on the wire surface is modeled with the Net Emission Coefficient (NEC) and is mixed with heat conductivity through PLASIMO® software. A time-transient code for analyzing wire explosions driven by a slow current rise rate is developed. It solves a circuit equation coupled with one-dimensional (1D) equations for the copper electrical conductivity as a function of its physical state and Net Emission Coefficient (NEC) radiation. At first, an initial voltage drop over the copper wire, current, and temperature distribution at the time of expansion is derived. The experiments have demonstrated that wires remain rather uniform lengthwise during the explosion and can be simulated utilizing 1D simulations. Data from the first stage are then used as the initial conditions of the second stage, in which a simplified 1D model for high-Mach-number flows is adopted to describe the expansion of the core. The current was carried by the vaporized wire material before it was dispersed in nitrogen by the shock wave. In the third stage, using a three-dimensional model of the test bench, the streamer threshold is estimated. Electrical breakdown voltage is calculated without solving a full-blown plasma model by integrating Townsend growth coefficients (TdGC) along electric field lines. BOLSIG⁺ and LAPLACE databases are used to calculate the TdGC at different mixture ratios of nitrogen/copper vapor. The simulations show both radiation and heat conductivity should be considered for an adequate description of wire resistance, and gaseous discharges start at lower voltages than expected due to ultraviolet radiation and the exploding shocks, which may have ionized the nitrogen.

Keywords: exploding wire, Townsend breakdown mechanism, streamer, metal vapor, shock waves

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