Search results for: robust back-‎stepping control

Authors: Grace Rachid, Mutasem El Fadel, Mahmoud Al Hindi, Ibrahim Jamali, Daniel Abdel Nour

Abstract:

This study examines the feasibility of indirect solar desalination in oil producing countries in the Middle East and North Africa (MENA) region. It relies on value engineering (VE) and cost-benefit with sensitivity analyses to identify optimal coupling configurations of desalination and solar energy technologies. A comparative return on investment was assessed as a function of water costs for varied plant capacities (25,000 to 75,000 m3/day), project lifetimes (15 to 25 years), and discount rates (5 to 15%) taking into consideration water and energy subsidies, land cost as well as environmental externalities in the form of carbon credit related to greenhouse gas (GHG) emissions reduction. The results showed reverse osmosis (RO) coupled with photovoltaic technologies (PVs) as the most promising configuration, robust across different prices for Brent oil, discount rates, as well as different project lifetimes. Environmental externalities and subsidies analysis revealed that a 16% reduction in existing subsidy on water tariffs would ensure economic viability. Additionally, while land costs affect investment attractiveness, the viability of RO coupled with PV remains possible for a land purchase cost < $ 80/m2 or a lease rate < $1/m2/yr. Beyond those rates, further subsidy lifting is required.

Keywords: solar energy, desalination, value engineering, CBA, carbon credit, subsidies

Procedia PDF Downloads 562

Authors: A. Luli, A. Santona

Abstract:

It is rare for individuals that are involved in a relationship to think about the possibility of having procreation problems in the near present or in the future. However, infertility is a condition that affects millions of people all around the world. Often, infertile individuals have to deal with experiences of psychological, relational and social problems. In these cases, they have to review their choices and take into consideration, if it is necessary, new ones. Different studies have examined the different decisions that infertile individuals have to go through dealing with infertility and its treatment, but none of them is focused on the decision-making style used by infertile individuals to solve their problem and on the factors that influences it. The aim of this paper is to define the style of decision-making used by infertile persons to give a solution to the ‘problem’ and the potential predictive role of the attachment and of the dyadic adjustment. The total sample is composed by 251 participants, divided in two groups: the experimental group composed by 114 participants, 62 males and 52 females, age between 25 and 59 years, and the control group composed by 137 participants, 65 males and 72 females, age between 22 and 49 years. The battery of instruments used is composed by: the General Decision Making Style (GDMS), the Experiences in Close Relationships Questionnaire Revised (ECR-R), Dyadic Adjustment Scale (DAS), and the Symptom Checklist-90-R (SCL-90-R). The results from the analysis of the samples showed a prevalence of the rational decision-making style for both males and females. No significant statistical difference was found between the experimental and control group. Also the analyses showed a significant statistical relationship between the decision making styles and the adult attachment styles for both males and females. In this case, only for males, there was a significant statistical difference between the experimental and the control group. Another significant statistical relationship was founded between the decision making styles and the adjustment scales for both males and females. Also in this case, the difference between the two groups was founded to be significant only of males. These results contribute to enrich the literature on the subject of decision-making styles in infertile individuals, showing also the predictive role of the attachment styles and the adjustment, confirming in this was the few results in the literature.

Keywords: adjustment, attachment, decision-making style, infertility

Procedia PDF Downloads 313

Authors: Milad Pirali, Sohrab Keyhani, Mohhamad Ali Sanjari, Ali Ashraf Jamshidi

Abstract:

Purpose: The effect of hamstring antagonist activity on the knee extensors torque of the Anterior Cruciate Ligament reconstruction (ACLR) is not clear and persistent muscle weakness is common after ACLR. Hamstring activation when acting as antagonist is considered very important for knee strengths. Therefore the purpose of this study was to examine hamstring antagonist coactivation during maximal effort of the isokinetic knee extension in ACLR athletes with hamstring autograft. Materials and Methods: We enrolled 20 professional athletes who underwent primary ACLR (hamstring tendon autograft)with 6-24 months postoperative and 20 healthy subjects as control group. Each subjects performed maximal effort isokinetic knee extension and flexion in 60/˚ s and 180/˚ s velocities for the involved and uninvolved limb. Synchronously, surface electromyography (EMG) was recorded of vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF) and biceps femoris (BF). The antagonist integrated EMG (IEMG) values were normalized to the IEMG of the same muscle during maximal isokinetic eccentric effort at the same velocities and ROM. Results: A one-way analysis of variance designs shows significantly greater IEMG coactivation of hamstring and decreased activation of Vm in ACLR when compared to uninvolved and control group leg in 60/˚ s and 180/˚ s velocities. Likewise peak torque to body weight was decreased in ACLR compared to uninvolved and control group during knee extension in both velocities (p < 0.05). Conclusions: Decreased extensors moment caused by decreased quadriceps inhibition and increased hamstring coactivation. In addition, these result indicated to decrease of motor unit recruitment in the VM (as a kinesiologicmonitore of the knee). It is appearing that strengthening of the quadriceps to be an important for rehabilitation program after ACLR for preparation in athletes endeavors. Therefore, we suggest that having more emphasis and focus on quadriceps strength and less emphasis on hamstring following ACLR.

Keywords: ACLR-coactivation, dynamometry, electromyography, isokinetic

Procedia PDF Downloads 238

Authors: Daneal Rorke, Gueguim Kana

Abstract:

The shift towards renewable energy sources for biofuel production has received increasing attention. However, the use and pre-treatment of lignocellulosic material are inundated with the generation of fermentation inhibitors which severely impact the feasibility of bioprocesses. This study reports the profiling of all volatile compounds generated during microwave assisted chemical pre-treatment of sorghum leaves. Furthermore, the optimization of reducing sugar (RS) from microwave assisted acid pre-treatment of sorghum leaves was assessed and gave a coefficient of determination (R2) of 0.76, producing an optimal RS yield of 2.74 g FS/g substrate. The development of an intelligent model to predict volatile compound fractions gave R2 values of up to 0.93 for 21 volatile compounds. Sensitivity analysis revealed that furfural and phenol exhibited high sensitivity to acid concentration, alkali concentration and S:L ratio, while phenol showed high sensitivity to microwave duration and intensity as well. These findings illustrate the potential of using an intelligent model to predict the volatile compound fraction profile of compounds generated during pre-treatment of sorghum leaves in order to establish a more robust and efficient pre-treatment regime for biofuel production.

Keywords: artificial neural networks, fermentation inhibitors, lignocellulosic pre-treatment, sorghum leaves

Procedia PDF Downloads 229

Authors: Samual Ayeni, A. S. Akinbani

Abstract:

At present when the price of petroleum is going down beyond bearable level, there is a need to diversify the economy towards arable crop production since Nigeria is an agrarian country. Yam plays prominent role in solving the problem of hunger in Nigeria. There is scarcity of information on the effect of fertilizers in increasing the yield of yam and maintaining soil properties in South Western Nigeria. This study was therefore set up to determine fertilizer effect on properties and yield of yam. The experiment was conducted at Adeyemi College of Education Teaching and Research Farm to compare the effect of organic, Organomineral and mineral fertilizers on yield of yam. Ten treatments were used 10t/ha Wood Ash, 10t/ha Cattle Dung, 10t/ha Poultry Manure, 10t/ha Manufactured Organic, 10t/ha Organomineral Fertilizer, 400kg/ha NPK, 400kg/ha SSP, 400kg/ha Urea and control with treatment. The treatments were laid out in a Randomized Complete Block Design (RCBD) and replicated three times. Compared with control, Organomineral fertilizer significantly (P < 0.05) increased the soil moisture content, poultry manure, wood ash significantly decreased (< 0.05) the bulk density. Application of 10t/ha Organomineral fertilizer recorded the highest increase in the yield of yam among the treatments.

Keywords: organomineral fertilizer, organic fertilizer, SSP, bulk density

Procedia PDF Downloads 281

Authors: Burak Bal

Abstract:

Mechanical characterization tests might come with a remarkable cost of time and money for both companies and academics. The inquiry to transform laboratory experiments to the computational media is getting a trend; accordingly, the literature supplies many analytical ways to explain the mechanics of deformation. In our work, we focused on the crystal plasticity finite element modeling (CPFEM) analysis on various materials in various crystal structures to predict the stress-strain curve without tensile tests. For FEM analysis, which we used in this study was ABAQUS, a standard user-defined material subroutine (UMAT) was prepared. The geometry of a specimen was created via DREAM 3D software with the inputs of Euler angles taken by Electron Back-Scattered Diffraction (EBSD) technique as orientation, or misorientation angles. The synthetic crystal created with DREAM 3D is also meshed in a way the grains inside the crystal meshed separately, and the computer can realize interaction of inter, and intra grain structures. The mechanical deformation parameters obtained from the literature put into the Fortran based UMAT code to describe how material will response to the load applied from specific direction. The mechanical response of a synthetic crystal created with DREAM 3D agrees well with the material response in the literature.

Keywords: crystal plasticity finite element modeling, ABAQUS, Dream.3D, microstructure

Procedia PDF Downloads 138

Authors: Puchita Chokcharoenying

Abstract:

Polyphenols are the most abundant antioxidants found in plants, and they are highly effective at scavenging oxidative free radicals. Antioxidants are substances found in medicinal plants to help prevent heart disease, stroke, and some cancers. This study focused on evaluating the flavonoids content of Chrysanthemum Indicum and determine their antioxidant capacity by using DPPH and ABTS radical scavenging capacity assay. The total flavonoid content of C. indicumextract was determined and expressed as quercetin equivalents (QE)/g measured by an aluminiumchloride colorimetric method. The results showed that the IC50 of C. indicum extract were 83.57μg/mL ± 0.875 and52.57μg/mL ± 0.632for DPPH and ABTS, respectively. C. indicumextract exhibited antioxidant activities as a concentration dependent manner. In the DPPH assay, vitamin C was used as a positive control, whereas Trolox was used as a positive control in the ABTS assay. In summary, C. indicum extract is rich in flavonoids, which have potent antioxidant properties. Thus, C. indicum extract is a good source of antioxidants and can be developed for medicinal purposes. Nevertheless, more research on the antioxidant activity of C. indicum extract and in vivo antioxidant studies are still needed.

Keywords: ABTS assay, antioxidant, chrysanthemum indicum, DPPH assay, total flavonoid content

Procedia PDF Downloads 242

Authors: P. Kamphikul, P. Krachodnok, R. Wongsan

Abstract:

This paper presents the gain improvement of a sector antenna for mobile phone base station by using the new technique to enhance its gain for microstrip antenna (MSA) array without construction enlargement. The curved woodpile Electromagnetic Band Gap (EBG) has been utilized to improve the gain instead. The advantages of this proposed antenna are reducing the length of MSAs array but providing the higher gain and easy fabrication and installation. Moreover, it provides a fan-shaped radiation pattern, wide in the horizontal direction and relatively narrow in the vertical direction, which appropriate for mobile phone base station. The paper also presents the design procedures of a 1x8 MSAs array associated with U-shaped reflector for decreasing their back and side lobes. The fabricated curved woodpile EBG exhibits bandgap characteristics at 2.1 GHz and is utilized for realizing a resonant cavity of MSAs array. This idea has been verified by both the Computer Simulation Technology (CST) software and experimental results. As the results, the fabricated proposed antenna achieves a high gain of 20.3 dB and the half-power beam widths in the E- and H-plane of 36.8 and 8.7 degrees, respectively. Good qualitative agreement between measured and simulated results of the proposed antenna was obtained.

Keywords: gain improvement, microstrip antenna array, electromagnetic band gap, base station

Procedia PDF Downloads 297

Authors: Renate Gericke, Carol Long

Abstract:

Despite the robust empirical support of attachment, advancement in the description and conceptualization of attachment has been slow and has not significantly advanced beyond the identification of attachment security or type (namely, secure, avoidant, ambivalent and disorganized). This has continued despite papers arguing for theoretical refinement in the classification of attachment presentations. For thinking and practice to advance, it is critically important that these categories and their assessment be interrogated in different contexts and across developmental age. To achieve this, a quantitative design was used with descriptive and inferential statistics, and general linear models were employed to analyze the data. The Attachment Story Completion Test (ASCT) was administered to 105 children between the ages of eight and twelve from socio-economically deprived contexts with high exposure to trauma. A staggering 93% of the children had insecure attachments (specifically, avoidant 37%, disorganized 34% and ambivalent 22%) and attachment was more complex than currently conceptualized in the attachment literature. Primary attachment did not only present as one of four discreet categories, but 70% of the sample had a complex attachment with more than one type of maternal attachment style. Attachment intensity also varied along a continuum (between 1 and 5). The findings have implications for a) research that has not considered the potential complexity of attachment or attachment intensity, b) policy to more actively support mother-infant dyads, particularly in high-risk contexts and c) question the applicability of a western conceptualization of a primary maternal attachment figure in non-western collectivist societies.

Keywords: attachment, children at risk, middle childhood, non-western context

Procedia PDF Downloads 180

Authors: Zouhaier Nasr, Mohamed Nouri

Abstract:

The increase in greenhouse gases since the pre-industrial period is a real threat to disrupting the balance of marine and terrestrial ecosystems. Along with the oceans, forest soils are considered to be the planet's second-largest carbon sink. North African forests have been subject to alarming degradation for several decades. The objective of this investigation is to determine and quantify the effect of thinning practiced in pine forests in northern Tunisia on the storage of organic carbon in the trees and in the soil. The plot planted in 1989 underwent thinning in 2005 on to plots; the density is therefore 1600 trees/ha in control and 400 trees/ha in thinning. Direct dendrometric measurements (diameter, height, branches, stem) were taken. In the soil part, six profiles of 1m / 1m / 1m were used for soil and root samples and biomass and organic matter measurements. The measurements obtained were statistically processed by appropriate software. The results clearly indicate that thinning improves tree growth, so the diameter increased from 24.3 cm to 30.1 cm. Carbon storage in the trunks was 35% more and 25% for the whole tree. At ground level, the thinned plot shows a slight increase in soil organic matter and quantity of carbon per tree, exceeding the control by 10 to 25%.

Keywords: forest, soil, carbon, climate change, Tunisia

Procedia PDF Downloads 114

Authors: Chenhao Zhu

Abstract:

Quantitative mapping is playing a growing role in guiding urban planning, such as using a heat map created by CFX, CFD2000, or Envi-met, to adjust the master plan. However, there is no effective quantitative link between the mappings and planning formation. So, in many cases, the decision-making is still based on the planner's subjective interpretation and understanding of these mappings, which limits the improvement of scientific and accuracy brought by the quantitative mapping. Therefore, in this paper, an effort has been made to give a methodology of building a parametric link between the mapping and planning formation. A parametric planning process based on radiant mapping has been proposed for creating an urban green system. In the first step, a script is written in Grasshopper to build a road network and form the block, while the Ladybug Plug-in is used to conduct a radiant analysis in the form of mapping. Then, the research creatively transforms the radiant mapping from a polygon into a data point matrix, because polygon is hard to engage in the design formation. Next, another script is created to select the main green spaces from the road network based on the criteria of radiant intensity and connect the green spaces' central points to generate a green corridor. After that, a control parameter is introduced to adjust the corridor's form based on the radiant intensity. Finally, a green system containing greenspace and green corridor is generated under the quantitative control of the data matrix. The designer only needs to modify the control parameter according to the relevant research results and actual conditions to realize the optimization of the green system. This method can also be applied to much other mapping-based analysis, such as wind environment analysis, thermal environment analysis, and even environmental sensitivity analysis. The parameterized link between the mapping and planning will bring about a more accurate, objective, and scientific planning.

Keywords: parametric link, mapping, urban green system, radiant intensity, planning strategy, grasshopper

Procedia PDF Downloads 126

Authors: Nyoman Wijana, Chandra Arha

Abstract:

Disclosures of Intellectual Capital (IC) is a presentation of corporate information assets that are not recorded in the financial statements. This disclosures is very helpful because it provides inform corporate assets are intangible. In the new economic era, the company's intangible assets will determine company's competitive advantage. This study aimed to examine the effect of IC disclosures on market capitalization growth. Observational studies conducted over ten years in 2002-2011. The purpose of this study was to determine the effect for last ten years. One hundred samples of the company's largest market capitalization in 2011 traced back to last ten years. Data that used, are in 2011, 2008, 2005, and 2002 Method that’s used for acquiring the data is content analysis. The analytical method used is Ordinanary Least Square (OLS) and analysis tools are e views 7 This software using Pooled Least Square estimation parameters are specifically designed for panel data. The results of testing analysis showed inconsistent expression levels affect the growth of the market capitalization in each year of observation. The results of this study are expected to motivate the public company in Indonesia to do more voluntary IC disclosures and encourage regulators to make regulations in a comprehensive manner so that all categories of the IC must be disclosed by the company.

Keywords: IC disclosures, market capitalization growth, analytical method, OLS

Procedia PDF Downloads 328

Authors: M. J. Falade

Abstract:

Field experiment was conducted to compare the efficacy of hot water extracts of three plants (Ricinus communis, Jatropha gossypifolia and Datura stramonium) with benomyl in the control of cowpea anthracnose disease. Three concentrations of the extracts (65, 50 and 30%) were used in the study. Result from the experiment shows that all the extracts at the tested concentration reduced the incidence and severity of the disease. D. stramonium at 65% concentration compares favourably with that of benomyl fungicide in reducing incidence and severity of infection. At 65% concentration of D. stramonium, incidence of the disease was 22% on pooled mean basis, and this was not significantly different from that of benomyl (21%). Similarly, the percentage of normal seeds recorded at this same concentration of the extract was 85% and was not significantly different from that of benomyl (86%). In terms of disease severity trace infections were observed on the cowpea plants at this concentration of the extract and that of benomyl. However, at lower concentrations of all the extracts, significant variations were observed on incidence of disease and percentage of normal seeds such that values obtained from use of benomyl were higher than those obtained from the use of the extracts. The study, therefore, shows that extracts of these indigenous plants can be used as a substitute for the benomyl fungicide in the management of anthracnose disease.

Keywords: benomyl, C. lindemuthianum, disease incidence, disease severity

Procedia PDF Downloads 268

Authors: Mohamed A. Eid, Sobhy M. Aly, Marwa M. Ibrahim, Nadia L. Radwan

Abstract:

To investigate the interaction effects of vitamin D supplementation combined with aerobic exercises (AE) and conventional physical therapy program (CPTP) on balance and physical performance in children with Down syndrome (DS).Methods: A randomized controlled trial was conducted for 38 children with DS, with ages ranging from 8 to 12 years. They were divided randomly to two groups. The control group (n=19) received the CPTP, while the study group (n=19) received the CPTP, AE, and vitamin D in the form of an oral daily dose of vitamin D3 400 IU (Cholecalciferol). Evaluation of balance by using the Biodex Stability System and physical performance by using the six-minute walk test (6MWT)was performed before and after 12 weeks of the treatment program. Findings: All groups showed a significant improvement in balance and physical performance after treatment (p < 0.05). The study group showed a significant improvement in balance and physical performancecompared with that of the control group (p < 0.05). Conclusion: Vitamin D supplementation combined with AE and CPTP could improve balance and physical performance in children with DS. Therefore, vitamin D and AEshould be considered as adjunctive to the rehabilitation program of these children.

Keywords: aerobic exercises, balance, down syndrome, physical performance, vitamin D

Procedia PDF Downloads 212

Authors: Titus Amodu Umoru

Abstract:

The global economy today is full of sophistication. All over the world, business and marketing practices are undergoing an unprecedented transformation. In realization of this fact, the federal government of Nigeria has put in place a robust transformation agenda in order to put Nigeria in a better position to be a competitive player and in the process transform all sectors of its economy. New technologies, especially the internet, are the driving force behind this transformation. However, technology has inadvertently affected the way businesses are done thus necessitating the acquisition of new skills. In developing countries like Nigeria, citizens are still battling with effective application of those technologies. Obviously, students of business education need to acquire relevant business knowledge to be able to transit into the world of work on graduation from school and compete favourably in the labour market. Therefore, effective utilization of social media by both teachers and students can help extensively in empowering students with the needed skills. Social media which is described as a group of internet-based applications that build on the ideological foundations of Web 2.0, and which allow the creation and exchange of user-generated content, if incorporated into the classroom experience may be the needed answer to unemployment and poverty in Nigeria as beneficiaries can easily connect with existing and potential enterprises and customers, engage with them and reinforce mutual business benefits. Challenges and benefits of social media use in education in Nigeria universities were revealed in this study.

Keywords: business education, challenges, opportunities, utilization, social media

Procedia PDF Downloads 398

Authors: L. Wei Sheng, M. T. Noor Syazwanee, C. J. Carolyna, M. Amiruddin, M. Pauziah

Abstract:

This paper exhibits the alternatives towards active suspension systems revised based on the classical passive suspension system to improve comfort and handling performance. An active Magneto rheological (MR) suspension system is proposed as to explore the active based suspension system to enhance performance given its freedom to independently specify the characteristics of load carrying, handling, and ride quality. Malaysian quarter car with two degrees of freedom (2DOF) system is designed and constructed to simulate the actions of an active vehicle suspension system. The structure of a conventional twin-tube shock absorber is modified both internally and externally to comprehend with the active suspension system. The shock absorber peripheral structure is altered to enable the assembling and disassembling of the damper through a non-permanent joint whereby the stress analysis of the designed joint is simulated using Finite Element Analysis. Simulation on the internal part where an electrified copper coil of 24AWG is winded is done using Finite Element Method Magnetics to measure the magnetic flux density inside the MR damper. The primary purpose of this approach is to reduce the vibration transmitted from the effects of road surface irregularities while maintaining solid manoeuvrability. The aim of this research is to develop an intelligent control system of a consecutive damping automotive suspension system. The ride quality is improved by means of the reduction of the vertical body acceleration caused by the car body when it experiences disturbances from speed bump and random road roughness. Findings from this research are expected to enhance the quality of ride which in return can prevent the deteriorating effect of vibration on the vehicle condition as well as the passengers’ well-being.

Keywords: active suspension, FEA, magneto rheological damper, Malaysian quarter car model, vibration control

Procedia PDF Downloads 197

Authors: Usman Mir Khan, Ishtiaque Ahmad, Saima Inayat, H. M. Arslan Amin, Muhammad Ayaz, Nisar Ahmad

Abstract:

Citrus reticulata Blanco crude flowers extract (CFE) at four different concentration (1, 2, 3 and 4%, v/v) were used as natural milk coagulant instead of rennet to apply for Cheddar cheese making from buffalo milk. The physicochemical properties and nutrition composition of Cheddar cheeses were compared with cheese made with 0.002% (v/v) rennet (control cheese). Physico-chemical of Cheddar cheese showed that cheese made with 1% and 2% of CFE had a crumbly and slightly softer texture of cheese. While, cheeses containing 3 and 4% CFE had semi-hard textural properties of curd similar to rennet added cheese. The CFE made cheese had moisture 37 %, fat 45 % on dry basis similar to rennet made Cheddar cheese. Protein analysis shows that CFE made cheese had significant higher protein content than control. The Cheddar cheese with 3% and 1% CFE were preferred by consumers instead of 2% and 4% CFE for their taste, texture/appearance and overall acceptability. Conclusively, CFE coagulated Cheddar cheese fulfills the nutritional requirement with acceptable organoleptic characteristics and at the same time provides nutritional health benefits.

Keywords: cheddar cheese, Citrus reticulata Blanco, buffalo milk, milk coagulant

Procedia PDF Downloads 291

Authors: Kai-Chee Loh, Jingxin Zhang, Yen-Wah Tong

Abstract:

Hydrolysis and acidogenesis are the rate-controlling steps in an anaerobic digestion (AD) process. Considering that the optimum conditions for each stage can be diverse diverse, the development of a multi-stage AD system is likely to the AD efficiency through individual optimization. In this research, we developed a highly integrate three-stage anaerobic digester (HM3) to combine the advantages of dry AD and wet AD for anaerobic co-digestion of food waste and horse manure. The digester design comprised mainly of three chambers - high-solids hydrolysis, high-solids acidogenesis and wet methanogensis. Through comparing the treatment performance with other two control digesters, HM3 presented 11.2 ~22.7% higher methane yield. The improved methane yield was mainly attributed to the functionalized partitioning in the integrated digester, which significantly accelerated the solubilization of solid organic matters and the formation of organic acids, as well as ammonia in the high-solids hydrolytic and acidogenic stage respectively. Additionally, HM3 also showed the highest volatile solids reduction rate among the three digesters. Real-time PCR and pyrosequencing analysis indicated that the abundance and biodiversity of microorganisms including bacteria and archaea in HM3 was much higher than that in the control reactors.

Keywords: anaerobic digestion, high-solids, food waste and horse manure, microbial community

Procedia PDF Downloads 400

Authors: Gi-Beom Park, Hyong-Gi Park, Seong-Yong Lee, Jaeho Choi, Seok Hong Min, Tae Kwon Ha

Abstract:

The Nb silicide-based alloy has the excellent high-temperature strength and relatively lower density than the Ni-based superalloy; therefore, it has been receiving a lot of attention for the next generation high-temperature material. To enhance the high temperature creep property and oxidation resistance, Si was added to the Nb-based alloy, resulting in a multi-phase microstructure with metal solid solution and silicide phase. Since the silicide phase has a low machinability due to its brittle nature, it is necessary to fabricate components using the powder metallurgy. However, powder manufacturing techniques for the alloys have not yet been developed. In this study, we tried to fabricate Nb-based alloy powder by the hydrogenation-dehydrogenation reaction. The Nb-based alloy ingot was prepared by vacuum arc melting and it was annealed in the hydrogen atmosphere for the hydrogenation. After annealing, the hydrogen concentration was increased from 0.004wt% to 1.22wt% and Nb metal phase was transformed to Nb hydride phase. The alloy after hydrogenation could be easily pulverized into powder by ball milling due to its brittleness. For dehydrogenation, the alloy powders were annealed in the vacuum atmosphere. After vacuum annealing, the hydrogen concentration was decreased to 0.003wt% and Nb hydride phase was transformed back to Nb metal phase.

Keywords: Nb alloy, Nb metal and silicide composite, powder, hydrogenation-dehydrogenation reaction

Procedia PDF Downloads 231

Authors: Yunjia Yang, Peng Li, Gordon Xu, Timothy Mahony, Bing Zhang, Neena Mitter, Karishma Mody

Abstract:

Sheep flystrike is one of the most economically important diseases affecting the Australian sheep and wool industry (>356M/annually). Currently, control of Lucillia cuprina relies almost exclusively on chemicals controls, and the parasite has developed resistance to nearly all control chemicals used in the past. It is, therefore, critical to develop an alternative solution for the sustainable control and management of flystrike. RNA interference (RNAi) technologies have been successfully explored in multiple animal industries for developing parasites controls. This research project aims to develop a RNAi based biological control for sheep blowfly. Double-stranded RNA (dsRNA) has already proven successful against viruses, fungi, and insects. However, the environmental instability of dsRNA is a major bottleneck for successful RNAi. Bentonite polymer (BenPol) technology can overcome this problem, as it can be tuned for the controlled release of dsRNA in the gut challenging pH environment of the blowfly larvae, prolonging its exposure time to and uptake by target cells. To investigate the potential of BenPol technology for dsRNA delivery, four different BenPol carriers were tested for their dsRNA loading capabilities, and three of them were found to be capable of affording dsRNA stability under multiple temperatures (4°C, 22°C, 40°C, 55°C) in sheep serum. Based on stability results, dsRNA from potential targeted genes was loaded onto BenPol carriers and tested in larvae feeding assays, three genes resulting in knockdowns. Meanwhile, a primary blowfly embryo cell line (BFEC) derived from L. cuprina embryos was successfully established, aim for an effective insect cell model for testing RNAi efficacy for preliminary assessments and screening. The results of this study establish that the dsRNA is stable when loaded on BenPol particles, unlike naked dsRNA rapidly degraded in sheep serum. The stable nanoparticle delivery system offered by BenPol technology can protect and increase the inherent stability of dsRNA molecules at higher temperatures in a complex biological fluid like serum, providing promise for its future use in enhancing animal protection.

Keywords: lucilia cuprina, primary cell line establishment, RNA interference, insect cell transfection

Procedia PDF Downloads 61

Authors: Ewuola E. O., Sokunbi O. A., Oyedemi O. M., Sanni K. M

Abstract:

Moringa oleifera leaf has been traditionally used in the local medicine as an ingredient in some herbal formulations for blood purifier, cholesterol reducing agent, immune and reproductive enhancers. Twenty-four pubertal rabbit are divided equally into four groups were administered with varied concentrations of crude extract of the leaves of Moringa oleifera gavage at doses of 2.5ml/kg body weight (BW) in every 48 hours for 63 days. These rabbits were allotted into four treatments and each treatment was replicated six times to investigate the effect of administered crude Moringa oleifera leaf extract (CMOLE) on haematology and reproductive performance of pubertal rabbit does. Four experimental treatments were used. The animals on the control (T1) were administered water only. Rabbits on treatments 2, 3, and 4 were administered 100ml CMOLE/L, 200ml CMOLE/L, and 300ml CMOLE/L, respectively. The does were placed on extract two weeks before mating, five weeks after mating and continued for another two weeks after kindling. Six proven untreated bucks were used for the mating of the twenty-four treated does and these bucks were randomly allotted to the does such that each buck mated at least one treated does in each treatment. The same management practices and experimental diets were given ad libitum to all animals. Blood was sampled from the gestating does at the third trimester for haematological analysis. The haematology results showed that treated rabbits with 100ml CMOLE/L with mean corpuscular volume value of 93.38fl significantly (p < 0.05) higher than those on the control which is water only (82.24fl) but not significantly different from T3 (200ml CMOLE/L) and T4 (300ml CMOLE/L) which had mean values of 91.69fl and 91.49fl, respectively. While the erythrocyte counts, leukocyte counts, haematocrit, haemoglobin concentration, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, lymphocyte, neutrophil, monocyte, and eosinophil count were not significantly different across the treatments. For platelets, treated animals on T2 (100ml CMOLE/L) had the highest numerical value of 148.80 x 109/L which was identical with those on T3 (200ml CMOLE/L) with mean value of 141.50x109/L but significantly (p < 0.05) higher than those on T4 (300ml CMOLE/L) with mean value of 135.00 x 109/L and those on the control which had the least mean value of 126.60 x 109/L. The percentage conception rate of the treated animals was higher than those in the control group. The animals administered 300ml CMOLE/L had the apparently highest litter size of 5.75, while gestation length and litter weight tended to decline with increase in CMOLE concentrations The investigation demonstrated the potential effect of crude Moringa oleifera leaf extract on pubertal rabbit does. The administration of up to 300ml crude Moringa oleifera leaf extract per liter did not adversely affect but improved the haematological response and reproductive potential in gestating rabbit does.

Keywords: conception, haematology, moringa leaf extract, rabbit does

Procedia PDF Downloads 498

Authors: Mohammed Nishat, Ahmad Ghazali

Abstract:

This study empirically examines the corporate governance and firm performance, and tries to evaluate the governance, ownership and control related variables which are hypothesized to affect on firms performance. This study tries to evaluate the effectiveness of corporate governance mechanism to achieve high level performance among companies listed on the Karachi Stock Exchange (KSE) over the period from 2005 to 2008. To measure the firm performance level this research uses three measures of performance; Return on assets (ROA), Return on Equity (ROE) and Tobin’s Q. To link the performance of firms with the corporate governance three categories of corporate governance variables are tested which includes governance, ownership and control related variables. Fixed effect regression model is used to test the link between corporate governance and firm performance for 267 KSE listed Pakistani firms. The result shows that corporate governance variables such as percentage block holding by individuals have positive impact on firm performance. When CEO is also the chairperson of board then it is found that firm performance is adversely affected. Also negative relationship is found between share held by insiders and performance of firm. Leverage has negative impact on the performance of the firm and firm size is positively related with the firms performance.

Keywords: corporate governance, performance, agency cost, Karachi stock market

Procedia PDF Downloads 337

Authors: Rabia Göçmen, Gülşah Kanbur, Sinan Sefa Parlat

Abstract:

In this study, in the breeding Japanese quails (coturnix coturnix japonica), it was aimed to study the effects of cellular insulin receptor stimulation on the performance, some blood parameters, and hatchability features. In the study, a total of 84 breeding quails were used, which are in 6 weeks age, and whose 24 are male and 60 female. In the trial, rations which contain 2900 kcal/kg metabolic energy; crude protein of 20%, and water whose pH is calibrated to 7.45 were administered as ad-libitum, to the animals, as metformin source, metformin-HCl was used and as chrome resource, Chromium Picolinate. Trial groups were formed as control group (basal ration), metformin group (basal ration, added metformin at the level of fodder of 20 mg/kg), and chromium picolinate group (basal ration, added fodder of 1500 ppb Cr. When regarded to the results of performance at the end of trial, it is seen that live weight gain, fodder consumption, egg weight, fodder evaluation coefficient, and egg production were affected at the significant level (p < 0.05). When the results are evaluated in terms of incubation features at the end of trial, it was identified that incubation yield and hatchability are not affected by the treatments but in the groups, in which metformin and chromium picolinate are added to ration, that fertility rose at the significant level compared to control group (p < 0,05). According to the results of blood parameters and hormone at the end of the trial, while the level of plasma glucose level was not affected by treatments (p > 0.05), with the addition of metformin and chromium picolinate to ration, plasma, total control, cholesterol, HDL, LDL, and triglyceride levels were significantly affected from insulin receptor stimulators added to ration (p<0,05). Hormone level of Plasma T3 and T4 were also affected at the significant level from insulin receptor stimulators added to ration (p < 0,05).

Keywords: cholesterol, chromium picolinate, hormone, metformin, performance, quail

Procedia PDF Downloads 191

Authors: N. P. Eswara Reddy, S. Thahir Basha

Abstract:

Here, we report the success stories of potential leaf, seed and root endophytes against soil borne as well as foliar plant pathogens which are nutritionally adequate and safe for consumption. Endophytes are the microorganisms that reside asymptomatically in the tissues of higher plants are a robust source of potential biocontrol agents and it is presumed that the survival ability of endophytes may be better when compared to phylloplane microflora. Of all the 68 putative leaf endophytes, the endophytes viz., EB9 (100%), and EB35 (100%) which were superior in controlling Colletotrichum gloeosporioides causing mango anthracnose were identified as Brevundimonas bullata (EB09) and Bacillus thuringiensis (EB35) and further delayed in ripening of mango fruits up to 21 days. As a part, the seed endophyte GSE-4 was identified as Archoromobacter spp. against Sclerotium rolfsii causing stem rot of groundnut and the root endophyte REB-8 against Rhizoctonia bataticola causing dry root rot of chickpea was identified as Bacillus subtilis. Both recorded least percent disease incidence (PDI) and increased plant growth promotion, respectively. Further, the novel Bacillus subtilis (SEB-2) against Macrophomina pahseolina causing charcoal rot of sunflower provides an ample scope for exploring the endophytes at large scale. The talc-based formulations of these endophytes developed can be commercialized after toxicological studies. At the bottom line these unexplored endophytes are the need of the hour against aggressive plant pathogens and to maintain the quality and abundance of food and feed and also to fetch marginal economy to the farmers will be discussed.

Keywords: endophytes, plant pathogens, commercialization, abundance of food

Procedia PDF Downloads 406

Authors: Chia-Ju Peng, Shih-Jui Chen

Abstract:

This paper proposes a method to discriminate electroencephalogram (EEG) signals between different concentration states using empirical mode decomposition (EMD). Brain-computer interface (BCI), also called brain-machine interface, is a direct communication pathway between the brain and an external device without the inherent pathway such as the peripheral nervous system or skeletal muscles. Attention level is a common index as a control signal of BCI systems. The EEG signals acquired from people paying attention or in relaxation, respectively, are decomposed into a set of intrinsic mode functions (IMF) by EMD. Fast Fourier transform (FFT) analysis is then applied to each IMF to obtain the frequency spectrums. By observing power spectrums of IMFs, the proposed method has the better identification of EEG attention level than the original EEG signals between different concentration states. The band power of IMF3 is the most obvious especially in β wave, which corresponds to fully awake and generally alert. The signal processing method and results of this experiment paves a new way for BCI robotic system using the attention-level control strategy. The integrated signal processing method reveals appropriate information for discrimination of the attention and relaxation, contributing to a more enhanced BCI performance.

Keywords: biomedical engineering, brain computer interface, electroencephalography, rehabilitation

Procedia PDF Downloads 378

Authors: Maciej Dudek, Robert Kruszewski, Janusz Kudla, Konrad Walczyk

Abstract:

In this paper, we study how taxation of bequests affects human capital formation in the long term and short term horizon. Our underlying model is an overlapping generation model (OLG) with some degree of altruism on the part of the ancestors' generation towards their descendants. We ask the question in three separate frameworks. First, we study a simple one-sector model where a proxy of human capital is wage income. It the steady-state -for CRRA utility function and human capital produced with non-decreasing returns -the taxation of bequests is neutral to the accumulation of human capital. In the second framework, neutrality applies to the growth rates of human capital, physical capital, and consumption. In this case, taxation increases the level of bequests, leading to a lower value of current consumption. Finally in we consider two periods model instead of infinite horizon model as long as the tax revenue is at least partially rebated back to the public, the fraction of human capital engaged in the process of formation of human capital increases with the tax rate on bequests. In other words, taxation of bequests is partially offset by an increase in human capital formation. Higher human capital allows the future generation to earn higher wages, and today's generation can find it optimal to endow the future generation with more human capital when taxation is imposed on physical capital transferred to the next generation.

Keywords: taxation, bequests, policy, human capital

Procedia PDF Downloads 154

Authors: Meng-Hao Chen, Jeng-Der Huang, Chia-Ray Chen

Abstract:

With the new space mission need of high power dissipation, low thermal inertia and cyclical operation unit, such as high power amplifier (HPA) for synthetic aperture radar (SAR) satellite, the development of phase change material (PCM) technology seems to be a proper solution. Generally, the expected benefit of PCM solution is to eliminate temperature variation and maintain the stability of electronic units by using the latent heat during phase change process. It can also result in advantages of decreased radiator area and heater power. However, the PCMs have a drawback of low thermal conductivity that leads to large temperature gradient between the heat source and PCM. This paper thus presents both experimental and simplified numerical investigations on configuration design of PCM’s container. A comparison was carried out between the container with and without internal pin-fins structure. The results showed the benefit of pin-fins that act as the heat transfer enhancer to improve the temperature uniformity during phase transition. Furthermore, thermal testing and measurements were presented for four PCM candidates (i.e. n-octadecane, n-eicosane, glycerin and gallium). The solidification and supercooling behaviors on different PCMs were compared with available literature data and discussed in this study

Keywords: phase change material (PCM), thermal control, solidification, supercooling

Procedia PDF Downloads 369

Authors: Rashi Mahato

Abstract:

Talent management represents an organization’s effort to attract, develop and retain highly skilled and valuable employees. The goal is to have people with capabilities and commitment needed for current and future organizational success. The organizational talent pool is its managerial talent referred to as leadership pipeline. It is managed through various systems and processes to help the organization source, reward, evaluate, develop and move employees into various functions and roles. The pipeline bends, turns, and sometimes breaks as organizations identify who is 'ready now' and who is 'on track' for larger leadership roles. From this perspective, talent management designs structured approach and a robust mechanism for high potential employees to meet organization’s needs. The paper attempts to provide a roadmap and a structured approach towards building a high performing organization through well-defined career path. Managers want career paths to be defined, so that an adequate number of individuals may be identified and prepared to fill future vacancies. Once career progression patterns are identified, more systematic forecasting of talent requirements is possible. For the development of senior management talent or leadership team, career paths are needed as guidelines for talent management across functional and organizational lines. Career path is one of the important tools for talent management and aligning talent with business strategy. This paper briefly describes the approach for career path and the concept of

Keywords: career path, career path framework, lateral movement, talent management

Procedia PDF Downloads 202

Authors: Jie Liu, Wei Wei, Chun-Ping Chang

Abstract:

Using a sample of 110 countries over the period 1984-2013, this paper examines the impacts of country risks on choosing a specific exchange rate regime (first by utilizing the Levy-Yeyati and Sturzenegger de facto classification and then robusting it by the IMF de jure measurement) relative to other regimes via the panel multinomial logit approach. Empirical findings are as follows. First, in the full samples case we provide evidence that government is more likely to implement a flexible regime, but less likely to adopt a fixed regime, under a low level of composite and financial risk. Second, we find that Eurozone countries are more likely to choose a fixed exchange rate regime with a decrease in the level of country risk and favor a flexible regime in response to a shock from an increase of risk, which is opposite to non-Eurozone countries. Third, we note that high-risk countries are more likely to choose a fixed regime with a low level of composite and political risk in the government, but do not adjust the exchange rate regime as a shock absorber when facing economic and financial risks. It is interesting to see that those countries with relatively low risk display almost opposite results versus high-risk economies. Overall, we believe that it is critically important to account for political economy variables in a government’s exchange rate policy decisions, especially for country risks. All results are robust to the panel ordered probit model.

Keywords: country risk, political economy, exchange rate regimes, shock absorber

Procedia PDF Downloads 287

Authors: Nadir Sidiqi

Abstract:

Biodiversity conservation is humanity’s building block to sustain lives - ultimately allowing all living and nonliving creatures to interact in a balanced proportion. Humanity’s challenge in the 21st century is to maintain biodiversity without harming the natural habitat of plants, animals and beneficial microorganisms. There are many good reasons to consider why biodiversity is important to every nation around the world, especially for a nation like Afghanistan. One of the major values of biodiversity is its economic value: biodiversity provides goods and services to the Afghan nation directly through links and components such as the maintenance of traditional crops, medicine, fruits, animals, grazing, fuel, timber, harvesting, fishing, hunting and related supplies. Biodiversity is the variety of the living components, such as humans, plants, animals, and microorganisms, and nonliving components interaction, including air, water, sunlight, soil, humidity and environmental factors in an area. There are many ways of gauging the value of biodiversity. As an ecosystem, biodiversity includes such benefits as soil fertility, erosion control, crop pollination, crop rotation, and pest control. The conservation of biodiversity is crucial for these benefits, which would be impossible to replace. Biodiversity conservation also has heritage values; this wealth of genetic diversity provides backup to rural people living close together.

Keywords: Afghanistan, biodiversity, conservation, economy, environment

Procedia PDF Downloads 509