Search results for: number of stages

Authors: Asaiel Mubark Al Hadi

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Background: A frequent anorectal condition known as hemorrhoids, sometimes known as piles, is characterized by a weakening of the anal cushion and the supporting tissue as well as spasms of the internal sphincter. Hemorrhoids are most frequently identified by painless bright red bleeding, prolapse, annoying grape-like tissue prolapse, itching, or a combination of symptoms. digital rectal examination (DRE) and anoscope are used to diagnose it. Constipation, a low-fiber diet, a high body- mass index (BMI), pregnancy, and a reduced physical activity are among the factors that are typically thought to increase the risk of hemorrhoids. Golighers is the most commonly used hemorrhoid classification scheme It is 4 degrees, which determines the degree of the event. The purpose of this study is to assess knowledge and awareness level of the causes and stages of Hemorrhoids in the public of Saudi Arabia. Method: This cross-sectional study was conducted in the Saudi Arabia between Oct 2022- Dec 2022. The study group included at least 384 aged above 18 years. The outcomes of this study were analyzed using the SPSS program using a pre-tested questionnaire. Results: The study included 1410 participants, 69.9% of them were females and 30.1% were males. 53.7% of participants aged 20- 30 years old. 17% of participants had hemorrhoids and 42% had a relative who had hemorrhoids. 42.8% of participants could identify stage 1 of hemorrhoids correctly, 44.7% identified stage 2 correctly, 46.7% identified stage 3 correctly and 58.1% identified stage 4 correctly. Only 28.9% of participants had high level of knowledge about hemorrhoids, 62.7% had moderate knowledge and 8.4% had low knowledge. Conclusion: In conclusion, Saudi general population has poor knowledge of hemorrhoids, their causes and their management approach. There was a significant association between knowledge scores of hemorrhoids with age, gender, residence area and employment.

Keywords: hemorrhoids, external hemorrhoid, internal hemorrhoid, anal fissure, hemorrhoid stages, prolapse, rectal bleeding

Procedia PDF Downloads 63

Authors: Vadood Mobini, Mansoreh Agazadeh Shahrivar, Parvin Hashemi Gelenjkhanlo, Hassan Vazifah

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Seed number is a function of dry matter accumulation, crop growth rate (CGR), photothermal quotient (PTQ) and temperature during a critical developmental period, which is around flowering in canola (Brassica napus L.). The objective of this experiment was to determine factors such as dry matter, CGR, temperature, and PTQ around flowering which affect seed number. The experiment was conducted at Agricultural Research Station of Gonbad, Iran, between 2005 and 2007. Two cultivars of canola (Hyola401 and RGS003), as subplots were grown at 5 sowing dates as main plots, spaced approximately 30 days apart, to obtain different environmental conditions during flowering. The experiment was arranged in two conditions, i.e., supplemental irrigation and rainfed. Seed number per unit area was a key factor for increasing seed yield. Late sowing dates made the critical period of flowering coincide with high temperatures, decreased days to the flowering, seed number per unit area and seed yield. Seed number was driven by the availability of carbohydrates around flowering. Seed number per unit area was maximized for the cultivars when exposed to the highest PTQ, and to the lowest temperature between the beginning of flowering to that of seed filling. The relationship of seed number with aboveground dry matter, CGR, temperature, and PTQ around flowering, over different environmental conditions, showed these variables were generally applicable to seed number determination.

Keywords: flowering, cultivar, seed filling, environmental conditions, seed yield

Procedia PDF Downloads 429

Authors: Pshtiwan Shafiq Ahmed

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The invasion of Iraq was a turning point in Iraq, destroying the economic infrastructure of several important strategic and historic cities, including Mosul, Anbar and Diyala, which will take decades to rebuild It left 18,805 people dead and 37,000 injured, destroying hundreds of villages and cities, displacing 2.3 million people, and increasing the number of orphans The increase in the number of windows and the destruction of society and the structure of the population so that the number of children, women and the elderly has increased. Religious clashes have increased and religious cleansing has begun, trying to eradicate Christianity, Yazidis and Kakais from the whole of Iraq, causing the largest number of Christians, Yazidis and Kakais to leave Iraq and many of them went missing.

Keywords: ISIS, population change, geographical change, Iraq

Procedia PDF Downloads 64

Authors: Sukhbaatar Dorj, Erdenebaatar Altangerel

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As alternative to existing e-government measuring models, here proposed a new customer centric, service oriented, simple approach for measuring countries e-Governments. If successfully implemented, built infrastructure will provide a single e-government index number for countries. Main schema is as follows. Country CIO or equal position government official, at the beginning of each year will provide to United Nations dedicated web site 4 numbers on behalf of own country: 1) Ratio of available online public services, to total number of public services, 2) Ratio of interagency inter ministry online public services to total number of available online public services, 3) Ratio of total number of citizen and business entities served online annually to total number of citizen and business entities served annually online and physically on those services, 4) Simple index for geographical spread of online served citizen and business entities. 4 numbers then combined into one index number by mathematical Average function. In addition to 4 numbers 5th number can be introduced as service quality indicator of online public services. If in ordering of countries index number is equal, 5th criteria will be used. Notice: This approach is for country’s current e-government achievement assessment, not for e-government readiness assessment.

Keywords: countries e-government index, e-government, infrastructure for measuring e-government, measuring e-government

Procedia PDF Downloads 300

Authors: Hinda Berghiche, Hamida Benradia, Noureddine Soltani

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Pesticides are widely used in crop production and are known to induce a major contamination of ecosystems especially in aquatic environments. The leaching of a large amount of pollutants derived from agricultural activities (fertilizers, pesticides) might contaminate rivers which diverse into the likes and estuarine and coastal environments affecting several organisms such as crustacean species. In this context, there is searched for new selective insecticides with minimal toxic effects on the environment and human health such as growth insect regulators (GIRs). The current study aimed to examine the impact of novaluron (CE 20%), a potent benzoylphenylurea derivative insecticide on mosquito larvae, against non-target shrimp, Palaemon adspersus (Decapoda, Palaemonidae). The compound was tested at two concentrations (0.91 mg/L and 4.30 mg/L) corresponding respectively to the LC50 and LC90 determined against fourth-instar larvae of Culiseta longiareolata (Diptera, Culicidae). The molting hormone titer was determined in the haemolymph by an enzyme-immunoassay, while chitin was measured in peripheral integument at different stages during the molting cycle. Under normal conditions, the haemolymphatic ecdysteroid concentrations increased during the molting cycle to reach peak at stage D. In the treated series, we note absence of the peak at stage D and an increase at stages B, C and D as compared to the controls. Concerning the chitin amounts, we observe an increase from stage A to stage C followed by a decrease at stage D. Exposition of shrimps to novaluron resulted in a significant decrease of values at all molting stages with a dose-response effect. Thus, the insecticide can present secondary effects on this non-target arthropod species.

Keywords: toxicology, novaluron, crustacean, palaemon adspersus, ecdysteroids, cuticle, chitin

Procedia PDF Downloads 226

Authors: Gabriela Estrada, Joaquim Lloveras

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Design for error-proofing assembly is a new DFX approach to prevent assembly issues since early design stages. Assembly issues that can happen during the life phases of a system such as: production, installation, operation, and replacement phases. This prevention is possible by designing the product with poka-yoke or error-proofing characteristics. This approach guide designers to make decisions based on poka-yoke assembly design requirements. As a result of applying these requirements designers are able to create solutions to prevent assembly issues for the product in development stage. This paper integrates the needs to design products in an error proofing way into the systematic approach of design process by Pahl and Beitz. A case study is presented applying this approach.

Keywords: poka-yoke, error-proofing, assembly issues, design process, life phases of a system

Procedia PDF Downloads 348

Authors: Gabriela Estrada, Joaquim Lloveras

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Design for error-proofing assembly is a new DFX approach to prevent assembly issues since early design stages. Assembly issues that can happen during the life phases of a system such as: production, installation, operation and replacement phases. This prevention is possible by designing the product with poka-yoke or error-proofing characteristics. This approach guide designers to make decisions based on poka-yoke assembly design requirements. As a result of applying these requirements designers are able to create solutions to prevent assembly issues for the product in development stage. This paper integrates the needs to design products in an error proofing way into the systematic approach of design process by Pahl and Beitz. A case study is presented applying this approach.

Keywords: poka-yoke, error-proofing, assembly issues, design process, life phases of a system

Procedia PDF Downloads 294

Authors: John M. Ikome, Martha E. Ikome, Therese Van Wyk

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Productivity optimization of a company can significantly increase the company’s output and productivity which can be in the form of corrective actions of ineffective activities, process simplification, and reduction of variations, responsiveness, and reduction of set-up-time which are all under the classification of waste within the manufacturing environment. Deriving a means to eliminate a number of these issues has a key importance for manufacturing organization. This paper focused on a number of industrial engineering techniques which include a cause and effect diagram, to identify and optimize the method or systems being used. Based on our results, it shows that there are a number of variations within the production processes that can significantly disrupt the expected output.

Keywords: optimization, fishbone, diagram, productivity

Procedia PDF Downloads 281

Authors: Hale Kirer Silva Lecuna, Beyza Aydin

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Health is one of the main components of human capital and sustainable development, and it is very important for economic growth. Health economics, which is an indisputable part of the science of economics, has five stages in general. These are health and development, financing of health services, economic regulation in the health, allocation of resources and efficiency of health services. A well-developed and efficient health sector plays a major role by increasing the level of development of countries. The most crucial pillars of the health sector are the hospitals that are divided into public and private. The main purpose of the hospitals is to provide more efficient services. Therefore the aim is to meet patients’ satisfaction by increasing the service quality. Health-related studies in Turkey date back to the Ottoman and Seljuk Empires. In the near past, Turkey applied 'Health Sector Transformation Programs' under different titles between 2003 and 2010. Our aim in this paper is to measure how effective these transformation programs are for the health sector, to see how much they can increase the efficiency of hospitals over the years, to see the return of investments, to make comments and suggestions on the results, and to provide a new reference for the literature. Within this framework, the public and private hospitals in Balıkesir, Bilecik, Bursa, Çanakkale, Edirne, Istanbul, Kirklareli, Kocaeli, Sakarya, Tekirdağ, Yalova will be examined by using Data Envelopment Analysis (DEA) for the years between 2000 and 2019. DEA is a linear programming-based technique, which gives relatively good results in multivariate studies. DEA basically estimates an efficiency frontier and make a comparison. Constant returns to scale and variable returns to scale are two most commonly used DEA methods. Both models are divided into two as input and output-oriented. To analyze the data, the number of personnel, number of specialist physicians, number of practitioners, number of beds, number of examinations will be used as input variables; and the number of surgeries, in-patient ratio, and crude mortality rate as output variables. 11 hospitals belonging to the Marmara region were included in the study. It is seen that these hospitals worked effectively only in 7 provinces (Balıkesir, Bilecik, Bursa, Edirne, İstanbul, Kırklareli, Yalova) for the year 2001 when no transformation program was implemented. After the transformation program was implemented, for example, in 2014 and 2016, 10 hospitals (Balıkesir, Bilecik, Bursa, Çanakkale, Edirne, İstanbul, Kocaeli, Kırklareli, Tekirdağ, Yalova) were found to be effective. In 2015, ineffective results were observed for Sakarya, Tekirdağ and Yalova. However, since these values are closer to 1 after the transformation program, we can say that the transformation program has positive effects. For Sakarya alone, no effective results have been achieved in any year. When we look at the results in general, it shows that the transformation program has a positive effect on the effectiveness of hospitals.

Keywords: data envelopment analysis, efficiency, health sector, Marmara region

Procedia PDF Downloads 107

Authors: Vani Singhal, Jitendra Parmar, Satyendra Singh Chouhan

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Unseen class discovery has now become an important part of a machine-learning algorithm to judge new classes. Unseen classes are the classes on which the machine learning model is not trained on. With the advancement in technology and AI replacing humans, the amount of data has increased to the next level. So while implementing a model on real-world examples, we come across unseen new classes. Our aim is to find the number of unseen classes by using a hierarchical-based active learning algorithm. The algorithm is based on hierarchical clustering as well as active sampling. The number of clusters that we will get in the end will give the number of unseen classes. The total clusters will also contain some clusters that have unseen classes. Instead of first discovering unseen classes and then finding their number, we directly calculated the number by applying the algorithm. The dataset used is for intent classification. The target data is the intent of the corresponding query. We conclude that when the machine learning model will encounter real-world data, it will automatically find the number of unseen classes. In the future, our next work would be to label these unseen classes correctly.

Keywords: active sampling, hierarchical clustering, open world learning, unseen class discovery

Procedia PDF Downloads 141

Authors: Peter Heimerl, Alexander Plaikner, Mike Peters

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Background and Significance of the Study: Family-run businesses are a decisive economic factor in the Alpine tourism and leisure industry. Within the next years, it is expected that a large number of family-run small and medium-sized businesses will transfer ownership due to demographic developments. Four stages of succession processes can be identified by several empirical studies: (1) the preparation phase, (2) the succession planning phase, (3) the development of the succession concept, (4) and the implementation of the business transfer. Family business research underlines the importance of individual's and family’s values: Especially leadership values address mainly the first phase, which strongly determines the following stages. Aim of the Study: The study aims at answering the following research question: Which leadership values are dominating during succession processes in family-run businesses in Austrian Alpine tourism industry? Methodology: Twenty-two problem-centred individual interviews with 11 transferors and their 11 transferees were conducted. Data analysis was carried out using the software program MAXQDA following an inductive approach to data coding. Major Findings: Data analysis shows that nine values particularly influence succession processes, especially during the vulnerable preparation phase. Participation is the most-dominant value (162 references). It covers a style of cooperation, communication, and controlling. Discipline (142) is especially prevailing from the transferor's perspective. It addresses entrepreneurial honesty and customer orientation. Development (138) is seen as an important value, but it can be distinguished between transferors and transferees. These are mainly focused on strategic positioning and new technologies. Trust (105) is interpreted as a basic prerequisite to run the family firm smoothly. Interviewees underline the importance to be able to take a break from family-business management; however, this is only possible when openness and honesty constitute trust within the family firm. Loyalty (102): Almost all interviewees perceive that they can influence the loyalty of the employees through their own role models. A good work-life balance (90) is very important to most of the transferors, especially for their employees. Despite the communicated importance of a good work-life-balance, but however, mostly the commitment to the company is prioritised. Considerations of regionality (82) and regional responsibility are also frequently raised. Appreciation (75) is of great importance to both the handover and the takeover generation -as appreciation towards the employees in the company and especially in connection with the family. Familiarity (66) and the blurring of the boundaries between private and professional life are very common, especially in family businesses. Familial contact and open communication with employees which is mentioned in almost all handing over. Conclusions: In the preparation phase of succession, successors and incumbents have to consider and discuss their leadership and family values of family-business management. Quite often, assistance is needed to commonly and openly discuss these values in the early stages of succession processes. A large majority of handovers fail because of these values. Implications can be drawn to support family businesses, e.g., consulting initiatives at chambers of commerce and business consultancies must address this problem.

Keywords: leadership values, family business, succession processes, succession phases

Procedia PDF Downloads 67

Authors: Zbigniew Czyz, Ksenia Siadkowska, Krzysztof Skiba, Karol Scislowski

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Today’s progress in the rotorcraft is mostly associated with an optimization of aircraft performance achieved by active and passive modifications of main rotor assemblies and a tail propeller. The key task is to improve their performance, improve the hover quality factor for rotors but not change in specific fuel consumption. One of the tasks to improve the helicopter is an active optimization of the main rotor providing for flight stages, i.e., an ascend, flight, a descend. An active interference with the airflow around the rotor blade section can significantly change characteristics of the aerodynamic airfoil. The efficiency of actuator systems modifying aerodynamic coefficients in the current solutions is relatively high and significantly affects the increase in strength. The solution to actively change aerodynamic characteristics assumes a periodic change of geometric features of blades depending on flight stages. Changing geometric parameters of blade warping enables an optimization of main rotor performance depending on helicopter flight stages. Structurally, an adaptation of shape memory alloys does not significantly affect rotor blade fatigue strength, which contributes to reduce costs associated with an adaptation of the system to the existing blades, and gains from a better performance can easily amortize such a modification and improve profitability of such a structure. In order to obtain quantitative and qualitative data to solve this research problem, a number of numerical analyses have been necessary. The main problem is a selection of design parameters of the main rotor and a preliminary optimization of its performance to improve the hover quality factor for rotors. This design concept assumes a three-bladed main rotor with a chord of 0.07 m and radius R = 1 m. The value of rotor speed is a calculated parameter of an optimization function. To specify the initial distribution of geometric warping, a special software has been created that uses a numerical method of a blade element which respects dynamic design features such as fluctuations of a blade in its joints. A number of performance analyses as a function of rotor speed, forward speed, and altitude have been performed. The calculations were carried out for the full model assembly. This approach makes it possible to observe the behavior of components and their mutual interaction resulting from the forces. The key element of each rotor is the shaft, hub and pins holding the joints and blade yokes. These components are exposed to the highest loads. As a result of the analysis, the safety factor was determined at the level of k > 1.5, which gives grounds to obtain certification for the strength of the structure. The construction of the joint rotor has numerous moving elements in its structure. Despite the high safety factor, the places with the highest stresses, where the signs of wear and tear may appear, have been indicated. The numerical analysis carried out showed that the most loaded element is the pin connecting the modular bearing of the blade yoke with the element of the horizontal oscillation joint. The stresses in this element result in a safety factor of k=1.7. The other analysed rotor components have a safety factor of more than 2 and in the case of the shaft, this factor is more than 3. However, it must be remembered that the structure is as strong as the weakest cell is. Designed rotor for unmanned aerial vehicles adapted to work with blades with intelligent materials in its structure meets the requirements for certification testing. Acknowledgement: This work has been financed by the Polish National Centre for Research and Development under the LIDER program, Grant Agreement No. LIDER/45/0177/L-9/17/NCBR/2018.

Keywords: main rotor, rotorcraft aerodynamics, shape memory alloy, materials, unmanned helicopter

Procedia PDF Downloads 126

Authors: Kamal Kaushik, Trisha, Dandapni, Sambit Nanda, A. Mukherjee, S. Pradhan

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INTRODUCTION: As complexity in radiotherapy practice and processes are increasing, there is a need to assure quality control to a greater extent. At present, no international literature available with regards to the optimal quality control indicators for radiotherapy; moreover, few clinical audits have been conducted in the field of radiotherapy. The primary aim is to improve the processes that directly impact clinical outcomes for patients in terms of patient safety and quality of care. PROCEDURE: A team of an Oncologist, a Medical Physicist and a Radiation Therapist was formed for weekly clinical audits of patient’s undergoing radiotherapy audits The stages for audits include Pre planning audits, Simulation, Planning, Daily QA, Implementation and Execution (with image guidance). Errors in all the parts of the chain were evaluated and recorded for the development of further departmental protocols for radiotherapy. EVALUATION: The errors at various stages of radiotherapy chain were evaluated and recorded for comparison before starting the clinical audits in the department of radiotherapy and after starting the audits. It was also evaluated to find the stage in which maximum errors were recorded. The clinical audits were used to structure standard protocols (in the form of checklist) in department of Radiotherapy, which may lead to further reduce the occurrences of clinical errors in the chain of radiotherapy. RESULTS: The aim of this study is to perform a comparison between number of errors in different part of RT chain in two groups (A- Before Audit and B-After Audit). Group A: 94 pts. (48 males,46 female), Total no. of errors in RT chain:19 (9 needed Resimulation) Group B: 94 pts. (61 males,33 females), Total no. of errors in RT chain: 8 (4 needed Resimulation) CONCLUSION: After systematic periodic clinical audits percentage of error in radiotherapy process reduced more than 50% within 2 months. There is a great need in improving quality control in radiotherapy, and the role of clinical audits can only grow. Although clinical audits are time-consuming and complex undertakings, the potential benefits in terms of identifying and rectifying errors in quality control procedures are potentially enormous. Radiotherapy being a chain of various process. There is always a probability of occurrence of error in any part of the chain which may further propagate in the chain till execution of treatment. Structuring departmental protocols and policies helps in reducing, if not completely eradicating occurrence of such incidents.

Keywords: audit, clinical, radiotherapy, improving functionality

Procedia PDF Downloads 54

Authors: M. Manzoor, J. N. Ahmad, R. M. Giblin Davis, N. Javed, M. S. Haider

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The invasive Red Palm Weevil (RPW) (Rhynchophorus ferrugineus [Olivier] (Coleoptera: Curculionidae) is one of the most destructive palm pests in the world. Synthetic pesticides are environmentally hazardous pest control strategies being used in the past with emerging need of eco-friendly biological approaches including microbial entomopathogens for RPW management. The sublethal effects of a single entomopathogenic fungus (EPF) Beauveria bassiana (WG-11) (Ascomycota: Hypocreales) and two entomopathogenic nematode (EPN) species Heterorhabditis bacteriophora (Poinar) and Steinernema carpocapsae (Weiser) (Nematoda: Rhabditida) were evaluated in various combinations against laboratory-reared 3rd, 5th and 8th instar larvae of RPW in laboratory assays. Individual and combined effects of both entomopathogens (EP) were observed after the pre-application of B. bassiana fungus at 1-2-week intervals. A number of parameters were measured after the application of sub-lethal doses of EPF such as diet consumption, development, frass production, mortality, and weight gain. Combined treatments were tested for additive and synergistic effects. Synergism was more frequently observed in B. bassiana and S. carpocapsae combined treatments than in B. bassiana and H. bacteriophora combinations. Early instar larvae of RPW were more susceptible than older instars. Synergistic effects were observed in the 3rd and 5th instars exposed to B. bassiana and S. carpocapsae at 0, 7 and 14-day intervals. Whereas, in 8th instar larvae, the synergistic effect was observed only in B. bassiana and S. carpocapsae treatments after 0 and 7 days intervals. EPN treatments decreased pupation, egg hatching and emergence of adults. Lethal effects of nematodes were also observed in all growth stages of R. ferrugineus. Reduced larval weight, increased larval, pre-pupal and pupal duration, reduced adult weight and life span were observed. Sub-lethal concentrations of both entomopathogens induced variations in the different developmental stages and reduced food consumption, frass production, growth, and weight gain. So, on the basis of results, it is concluded that synthetic pesticides should be replaced with environmentally friendly sustainable biopesticides.

Keywords: H. bacteriophora, S. carpocapsae, B. bassiana, mortality

Procedia PDF Downloads 132

Authors: Lydia Wahid, Mona F. Ahmed, Nevin Darwish

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The vehicle routing problem (VRP) consists of a group of customers that needs to be served. Each customer has a certain demand of goods. A central depot having a fleet of vehicles is responsible for supplying the customers with their demands. The problem is composed of two subproblems: The first subproblem is an assignment problem where the number of vehicles that will be used as well as the customers assigned to each vehicle are determined. The second subproblem is the routing problem in which for each vehicle having a number of customers assigned to it, the order of visits of the customers is determined. Optimal number of vehicles, as well as optimal total distance, should be achieved. In this paper, an approach for solving the first subproblem (the assignment problem) is presented. In the approach, a clustering algorithm is proposed for finding the optimal number of vehicles by grouping the customers into clusters where each cluster is visited by one vehicle. Finding the optimal number of clusters is NP-hard. This work presents a polynomial time clustering algorithm for finding the optimal number of clusters and solving the assignment problem.

Keywords: vehicle routing problems, clustering algorithms, Clarke and Wright Saving Method, agglomerative hierarchical clustering

Procedia PDF Downloads 364

Authors: Wlodzimierz Ogryczak, Michal Przyluski, Tomasz Sliwinski

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In problems of portfolio selection, the reward-risk ratio criterion is optimized to search for a risky portfolio with the maximum increase of the mean return in proportion to the risk measure increase when compared to the risk-free investments. In the classical model, following Markowitz, the risk is measured by the variance thus representing the Sharpe ratio optimization and leading to the quadratic optimization problems. Several Linear Programming (LP) computable risk measures have been introduced and applied in portfolio optimization. In particular, the Mean Absolute Deviation (MAD) measure has been widely recognized. The reward-risk ratio optimization with the MAD measure can be transformed into the LP formulation with the number of constraints proportional to the number of scenarios and the number of variables proportional to the total of the number of scenarios and the number of instruments. This may lead to the LP models with huge number of variables and constraints in the case of real-life financial decisions based on several thousands scenarios, thus decreasing their computational efficiency and making them hardly solvable by general LP tools. We show that the computational efficiency can be then dramatically improved by an alternative model based on the inverse risk-reward ratio minimization and by taking advantages of the LP duality. In the introduced LP model the number of structural constraints is proportional to the number of instruments thus not affecting seriously the simplex method efficiency by the number of scenarios and therefore guaranteeing easy solvability. Moreover, we show that under natural restriction on the target value the MAD risk-reward ratio optimization is consistent with the second order stochastic dominance rules.

Keywords: portfolio optimization, reward-risk ratio, mean absolute deviation, linear programming

Procedia PDF Downloads 382

Authors: Y. El Khchine, M. Sriti

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In the present work, the forced convection heat transfer and fluid flow past an unconfined semi-circular cylinder is investigated. The two-dimensional simulation is employed for Reynolds numbers ranging from 10 ≤ Re ≤ 200, employing air (Pr = 0.71) as an operating fluid with Newtonian constant physics property. Continuity, momentum, and energy equations with appropriate boundary conditions are solved using the Computational Fluid Dynamics (CFD) solver Ansys Fluent. Various parameters flow such as lift, drag, pressure, skin friction coefficients, Nusselt number, Strouhal number, and vortex strength are calculated. The transition from steady to time-periodic flow occurs between Re=60 and 80. The effect of the Reynolds number on heat transfer is discussed. Finally, a developed correlation of Nusselt and Strouhal numbers is presented.

Keywords: forced convection, semi-circular cylinder, Nusselt number, Prandtl number

Procedia PDF Downloads 88

Authors: Ayman M. El-Zahaby, Ahmed S. El-Gendy

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Aeration for wastewater is essential for the proper operation of aerobic treatment units where the wastewater normally has zero dissolved oxygen. This is due to the need of oxygen by the aerobic microorganisms to grow and survive. Typical aeration units for wastewater treatment require electric energy for their operation such as mechanical aerators or diffused aerators. The passive units are units that operate without the need of electric energy such as cascade aerators, spray aerators and tray aerators. In contrary to the cascade aerators and spray aerators, tray aerators require much smaller area foot print for their installation as the treatment stages are arranged vertically. To the extent of the authors knowledge, the design of tray aerators for the aeration purpose has not been presented in the literature. The current research concerns with an analytical study for the design of tray aerators for the purpose of increasing the dissolved oxygen in wastewater treatment systems, including an investigation on different design parameters and their impact on the aeration efficiency. The studied aerator shall act as an intermediate stage between an anaerobic primary treatment unit and an aerobic treatment unit for small scale treatment systems. Different free falling flow regimes were investigated, and the thresholds for transition between regimes were obtained from the literature. The study focused on the jetting flow regime between trays. Starting from the two film theory, an equation that relates the dissolved oxygen concentration effluent from the system was derived as a function of the flow rate, number of trays, tray area, spacing between trays, number and diameter of holes and the water temperature. A MATLab ® model was developed for the derived equation. The expected aeration efficiency under different tray configurations and operating conditions were illustrated through running the model with varying the design parameters. The impact of each parameter was illustrated. The overall system efficiency was found to increase by decreasing the hole diameter. On the other side, increasing the number of trays, tray area, flow rate per hole or tray spacing had positive effect on the system efficiency.

Keywords: aeration, analytical, passive, wastewater

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Authors: Khedidja Bouhadef, Imene Said Kouadri, Omar Rahli

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In this paper numerical investigation is performed to analyze natural convection heat transfer characteristics within a wavy-wall enclosure filled with fluid-saturated porous medium. The bottom wall which has the wavy geometry is maintained at a constant high temperature, while the top wall is straight and is maintained at a constant lower temperature. The left and right walls of the enclosure are both straight and insulated. The governing differential equations are solved by Finite-volume approach and grid generation is used to transform the physical complex domain to a computational regular space. The aim is to examine flow field, temperature distribution and heat transfer evolutions inside the cavity when Darcy number, Rayleigh number and undulations number values are varied. The results mainly indicate that the heat transfer is rather affected by the permeability and Rayleigh number values since increasing these values enhance the Nusselt number; although the exchanges are not highly affected by the undulations number.

Keywords: grid generation, natural convection, porous medium, wavy wall enclosure

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Authors: Muhammad Asghar, A. I. Bhatti, T. Izhar

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The three-wheeled auto-rickshaw with a two or four-stroke Gasoline, Liquid Petrolium Gas (LPG) or Compressed Natural Gas (CNG) engine is a petite, highly maneuverable vehicle and best suited for the small and heavily-congested roads and is an affordable means of transportation in Pakistan cities. However due to in-efficient engine design, it is a main cause of air-pollution in the shape of white smoke (CO2) (greenhouse gases) at the tail pipe. Due to the environmental pollution, a huge number of battery powered vehicles have been imported from all over the world to fulfill the need of country. Effect of degree of hybridization on fuel economy and acceleration performance has been discussed in this paper. From mild to full hybridization stages have been examined. Optimal level of hybridization ranges depending on the total driving power of vehicle are suggested. The degree of hybridization is varied and fuel economy is seen accordingly by using Advisor (NREL) software. The novel vehicle drive-train is modeled and simulated in the Advisor software.

Keywords: advisor, hybridization, fuel economy, Three-Wheeled Rickshaw

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Authors: Ella Tyuryumina, Alexey Neznanov

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This paper is devoted to mathematical modelling of the progression and stages of breast cancer. We propose Consolidated mathematical growth model of primary tumor and secondary distant metastases growth in patients with lymph nodes metastases (CoM-III) as a new research tool. We are interested in: 1) modelling the whole natural history of primary tumor and secondary distant metastases growth in patients with lymph nodes metastases; 2) developing adequate and precise CoM-III which reflects relations between primary tumor and secondary distant metastases; 3) analyzing the CoM-III scope of application; 4) implementing the model as a software tool. Firstly, the CoM-III includes exponential tumor growth model as a system of determinate nonlinear and linear equations. Secondly, mathematical model corresponds to TNM classification. It allows to calculate different growth periods of primary tumor and secondary distant metastases growth in patients with lymph nodes metastases: 1) ‘non-visible period’ for primary tumor; 2) ‘non-visible period’ for secondary distant metastases growth in patients with lymph nodes metastases; 3) ‘visible period’ for secondary distant metastases growth in patients with lymph nodes metastases. The new predictive tool: 1) is a solid foundation to develop future studies of breast cancer models; 2) does not require any expensive diagnostic tests; 3) is the first predictor which makes forecast using only current patient data, the others are based on the additional statistical data. Thus, the CoM-III model and predictive software: a) detect different growth periods of primary tumor and secondary distant metastases growth in patients with lymph nodes metastases; b) make forecast of the period of the distant metastases appearance in patients with lymph nodes metastases; c) have higher average prediction accuracy than the other tools; d) can improve forecasts on survival of breast cancer and facilitate optimization of diagnostic tests. The following are calculated by CoM-III: the number of doublings for ‘non-visible’ and ‘visible’ growth period of secondary distant metastases; tumor volume doubling time (days) for ‘non-visible’ and ‘visible’ growth period of secondary distant metastases. The CoM-III enables, for the first time, to predict the whole natural history of primary tumor and secondary distant metastases growth on each stage (pT1, pT2, pT3, pT4) relying only on primary tumor sizes. Summarizing: a) CoM-III describes correctly primary tumor and secondary distant metastases growth of IA, IIA, IIB, IIIB (T1-4N1-3M0) stages in patients with lymph nodes metastases (N1-3); b) facilitates the understanding of the appearance period and inception of secondary distant metastases.

Keywords: breast cancer, exponential growth model, mathematical model, primary tumor, secondary metastases, survival

Procedia PDF Downloads 282

Authors: R. M. Kashim

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The study investigates the conceptual and procedural knowledge of rational number in primary school teachers, specifically, the primary school teachers level of conceptual knowledge about rational number and the primary school teachers level of procedural knowledge about rational numbers. The study was carried out in Bauchi metropolis in Bauchi state of Nigeria. A Conceptual and Procedural Knowledge Test was used as the instrument for data collection, 54 mathematics teachers in Bauchi primary schools were involved in the study. The collections were analyzed using mean and standard deviation. The findings revealed that the primary school mathematics teachers in Bauchi metropolis posses a low level of conceptual knowledge of rational number and also possess a high level of Procedural knowledge of rational number. It is therefore recommended that to be effective, teachers teaching mathematics most posses a deep understanding of both conceptual and procedural knowledge. That way the most knowledgeable teachers in mathematics deliver highly effective rational number instructions. Teachers should not ignore the mathematical concept aspect of rational number teaching. This is because only the procedural aspect of Rational number is highlighted during instructions; this often leads to rote - learning of procedures without understanding the meanings. It is necessary for teachers to learn rational numbers teaching method that focus on both conceptual knowledge and procedural knowledge teaching.

Keywords: conceptual knowledge, primary school teachers, procedural knowledge, rational numbers

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Authors: Akın Kuyulu, Hanife Genç

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In present study, it was aimed to evaluate the gamma radiation impacts on tomato leaf miner at different biological stages. The laboratory colony of tomato leaf miner was used to set up the experiments. Different biological stages of the insects (eggs, 4^th instars and pupae) were irradiated using Cobalt-60 at doses of 0 (control), 100 Gray (Gy), 200 Gy, 300 Gy and 400 Gy in Cos-44HH-N source, at dose rate of 480 Gy/h. After irradiation, the eggs were incubated until hatching; the mature larvae were reared to complete their developments. Adult emergences from irradiated pupae were also evaluated. The results showed that there were no egg hatching at all tested irradiation doses. Although, the pupal percentages of irradiated mature larvae were 54%, 15% and 8% at doses of 100 Gy, 200 Gy and 300 Gy respectively, there were no adult emergences from irradiated mature larvae. On the other hand, the adult emergences were observed from irradiated pupae, decreased as radiation doses increased along with malformed adult appearance. Male and female individuals were out crossed with laboratory reared adults. Fecundity was correlated with radiation doses.

Keywords: irradiation, tomato, tomato leafminer, Tuta absoluta

Procedia PDF Downloads 216

Authors: H. Bhowmik, A. Faisal, Ahmed Al Yaarubi, Nabil Al Alawi

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Experiments are conducted to analyze the steady-state and the power-on transient natural convection heat transfer from a horizontal cylinder mounted in a vertical up flow circular duct. The heat flux ranges from 177 W/m² to 2426 W/m² and the Rayleigh number ranges from 1×10⁴ to 4.35×10⁴. For natural air flow and constant heat flux condition, the effects of heat transfer around the cylinder under steady-state condition are investigated. The steady-state results compare favorably with that of the available data. The effects of transient heat transfer data on different angular position of the thermocouple (0^o, 90^o, 180^o) are also reported. It is observed that the transient heat transfer around the cylinder is strongly affected by the position of thermocouples. In the transient region, the rate of heat transfer obtained at 90^o and 180^o are higher than that of stagnation point (0^o). Finally, the dependence of the average Nusselt number on Rayleigh number for steady and transient natural convection heat transfer are analyzed, and a correlation equation is presented.

Keywords: Fourier number, Nusselt number, Rayleigh number, steady state, transient

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Authors: Nurul Hamirah Kamsani, Mohd Hamim Rajikin, Nor Ashikin Mohamed Noor Khan, Sharaniza Abdul Rahim

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Cytoskeletal structures, in particular actin and tubulin, provide a fundamental framework in all cells, including embryos. Under influence of nicotine, the cytoskeletal organization may be subjected to oxidative stress (OS) insult and cause alteration. Tocotrienol-rich fraction (TRF) is proven to enhance fertility better than the other sub-group of Vitamin E, tocopherols (TCPs). The objective of this study was to evaluate the effects of TRF on 1) actin and tubulin of 2- and 8-cell murine embryos and 2) the regulation of reactive oxygen species (ROS)-scavenging enzymes; induced by nicotine. Twenty four female Balb/C were subjected to either subcutaneous (sc) injection of 0.9% NaCl; sc injection of 3.0 mg/kg bw/day nicotine; sc injection of 3.0 mg/kg bw/day nicotine + oral gavage (OG) of 60 mg/kg bw/day TRF; or OG of 60 mg/kg bw/day TRF for 7 consecutive days. After superovulation and mating, animals were euthanized. 2-cell developing embryos were retrieved. 50% of the retrieved embryos were visualized under confocal laser staining microscopy (CLSM) for alterations of actin and tubulin. The remaining amount of embryos was cultured in vitro until 8-cell stage followed by CLSM visualization. Blood plasma was subjected to OS assays. Plasma malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were determined and analysed accordingly. At both 2- and 8-cell developing stages, actin intensities were significantly reduced in the nicotine group (p<0.001). After the intervention, actin intensity was significantly increased compared to that of the nicotine group (p<0.001). The same trend was seen in tubulin at both cell stages. TRF has minimized the deleterious effects of nicotine in actin and tubulin of both 2- and 8-cell developmental stages during pre-implantation embryonic development in mice in vitro. Levels of endogenous anti-oxidative enzymes were sustained close to control accompanied by decreased levels of OS biomarker.

Keywords: actin, nicotine, pre-implantation embryos, tocotrienol rich fraction, tubulin

Procedia PDF Downloads 126

Authors: Ercan Ceyhan, Ali Kahraman, Hasan Dalgıç

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This research was made during the 2011 and 2012 growing periods according to “Randomized Blocks Design” with 3 replications. Research material was the following chickpea genotype: CA119, CA128, CA149, CA150, CA222, CA250, CA254 and other 2 commercial varieties named as Gökçe and Yaşa. Some agronomical characteristics such as plant height (cm), number of pod per plant, number of seed per pod, number of seed per plant, 1000 seed weight (g) and seed yield (kg ha-1) were determined. Statistically significant variations were found amongst the genotypes for all variables except seeds per pod. Means of the two years showed the range for plant height was from 52.83 cm (Gökçe) to 73.00 cm (CA150), number of pod per plant was from 14.00 (CA149) to 26.83 (CA261), number of seed per pod was from 1.10 (Gökçe) to 1.19 (CA149 ve CA250), number of seed per plant was from 16.28 (CA149) to 31.65 (CA261), 1000 seed weight was from 295.85 g (CA149) to 437.80 g (CA261) and seed yield was from 1342.73 kg ha-1 (CA261) to 2161.50 kg ha-1 (CA128). Results of the research implicated that the new developed lines were superior compared with the control (commercial) varieties by means of most of the characteristics.

Keywords: agricultural characters, chickpea, seed yield, genotype variations

Procedia PDF Downloads 180

Authors: Adnan Z. Mkhelif

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The production of number forms in English tends to be problematic for Iraqi learners of English as a foreign language (EFL), even at the undergraduate level. To help better understand and consequently address this problem, it is important to identify its sources. This study aims at: (1) statistically analysing Iraqi EFL undergraduates' performance in the production of number forms in English; (2) classifying learners' errors in terms of their possible major causes; and (3) outlining some pedagogical recommendations relevant to the teaching of number forms in English. It is hypothesized in this study that (1) Iraqi EFL undergraduates still face problems in the production of number forms in English and (2) errors pertaining to the context of learning are more numerous than those attributable to the other possible causes. After reviewing the literature available on the topic, a written test comprising 50 items has been constructed and administered to a randomly chosen sample of 50 second-year college students from the Department of English, College of Education, Wasit University. The findings of the study showed that Iraqi EFL undergraduates still face problems in the production of number forms in English and that the possible major sources of learners’ errors can be arranged hierarchically in terms of the percentages of errors to which they can be ascribed as follows: (1) context of learning (50%), (2) intralingual transfer (37%), and (3) interlingual transfer (13%). It is hoped that the implications of the study findings will be beneficial to researchers, syllabus designers, as well as teachers of English as a foreign/second language.

Keywords: L2 number forms, L2 vocabulary learning, productive knowledge, proficiency

Procedia PDF Downloads 115

Authors: Jarrod Haar, David Brougham

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The present study explores the links between supporting employee well-being and the potential benefits to employee performance. We focus on employee innovative work behaviors (IWBs), which have three stages: (1) development, (2) adoption, and (3) implementation of new ideas and work methods. We explore the role of organizational support focusing on employee well-being via High-Performance Work Systems (HPWS). HPWS are HR practices that are designed to enhance employees’ skills, commitment, and ultimately, productivity. HPWS influence employee performance through building their skills, knowledge, and abilities and there is meta-analytic support for firm-level HPWS influencing firm performance, but less attention towards employee outcomes, especially innovation. We explore HPWS-wellbeing being offered (e.g., EAPs, well-being App, etc.) to capture organizational commitment to employee well-being. Under social exchange theory, workers should reciprocate their firm's offering of HPWS-wellbeing with greater efforts towards IWBs. Further, we explore playful work design as a mediator, which represents employees proactively creating work conditions that foster enjoyment/challenge but don’t require any design change to the job itself. We suggest HPWS-wellbeing can encourage employees to become more playful, and ultimately more innovative. Finally, beyond direct effects, we examine whether these relations are similar by gender and ultimately test a moderated mediation model. Using N=1135 New Zealand employees, we established measures with confirmatory factor analysis (CFA), and all measures had good psychometric properties (α>.80). We controlled for age, tenure, education, and hours worked and analyzed data using the PROCESS macro (version 4.2) specifically model 8 (moderated mediation). We analyzed overall IWB, and then again across the three stages. Overall, we find HPWS-wellbeing is significantly related to overall IWBs and the three stages (development, adoption, and implementation) individually. Similarly, HPWS-wellbeing shapes playful work design and playful work design predicts overall IWBs and the three stages individually. It only partially mediates the effects of HPWS-wellbeing, which retains a significant indirect effect. Moderation effects are supported, with males reporting a more significant effect from HPWS-wellbeing on playful work design but not IWB (or any of the three stages) than females. Females report higher playful work design when HPWS-wellbeing is low, but the effects are reversed when HPWS-wellbeing is high (males higher). Thus, males respond stronger under social exchange theory from HPWS-wellbeing, at least towards expressing playful work design. Finally, evidence of moderated mediation effects is found on overall IWBs and the three stages. Males report a significant indirect effect from HPWS-wellbeing on IWB (through playful work design), while female employees report no significant indirect effect. The benefits of playful work design fully account for their IWBs. The models account for small amounts of variance towards playful work design (12%) but larger for IWBs (26%). The study highlights a gap in the literature on HPWS-wellbeing and provides empirical evidence of their importance towards worker innovation. Further, gendered effects suggest these benefits might not be equal. The findings provide useful insights for organizations around how providing HR practices that support employee well-being are important, although how they work for different genders needs further exploration.

Keywords: human resource practices, wellbeing, innovation, playful work design

Procedia PDF Downloads 57

Authors: Nuttawoot Nupo, Sayan Panma

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A semigroup S is said to be a left (right) zero semigroup if S satisfies the equation xy=x (xy=y) for all x,y in S. In addition, the semigroup S is called a left (right) group if S is isomorphic to the direct product of a group and a left (right) zero semigroup. The Cayley digraph Cay(S,A) of a semigroup S with a connection set A is defined to be a digraph with the vertex set S and the arc set E(Cay(S,A))={(x,xa) | x∈S, a∈A} where A is any subset of S. All sets in this research are assumed to be finite. Let D be a digraph together with a vertex set V and an arc set E. Let u and v be two different vertices in V and I a nonempty subset of V. The vertices u and v are said to be independent if (u,v)∉E and (v,u)∉E. The set I is called an independent set of D if any two different vertices in I are independent. The independence number of D is the maximum cardinality of an independent set of D. Moreover, the vertices u and v are said to be path independent if there is no dipath from u to v and there is no dipath from v to u. The set I is called a path independent set of D if any two different vertices in I are path independent. The path independence number of D is the maximum cardinality of a path independent set of D. In this research, we describe a lower bound and an upper bound of the independence number of Cayley digraphs of left groups and right groups. Some examples corresponding to those bounds are illustrated here. Furthermore, the exact value of the path independence number of Cayley digraphs of left groups and right groups are also presented.

Keywords: Cayley digraphs, independence number, left groups, path independence number, right groups

Procedia PDF Downloads 213

Authors: Adnan I. O. Zaid, Safwan M. A. Alqawabah

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Review of the available literature on grain refinement of aluminum and its alloys reveals that little work is published on the effect of refiners on mechanical characteristics and wear resistance. In this paper, the effect of addition of Zr to Al grain refined by Ti+B on its metallurgical, mechanical characteristics and wear resistance both in the as cast and after extrusion condition are presented and discussed. It was found that Addition of Zr to Al resulted in deterioration of its mechanical strength and hardness, whereas it resulted in improvement of both of them when added to Al grain refined by Ti+B. Furthermore it was found that the direct extrusion process resulted in further increase of the mechanical strength and hardness of Al and its micro-alloys. Also it resulted in increase of their work hardening index, n, i.e. improved their formability, hence it reduces the number of stages required for forming at large strains in excess of the plastic instability before Zr addition.

Keywords: aluminum, grain refinement, titanium + boron, zirconium, mechanical characteristics, wear resistance, direct extrusion

Procedia PDF Downloads 417