Search results for: cycle length

Authors: A. D. Parekh

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The present work describes relative contributions of operating parameters on required heat transfer area of three heat exchangers viz. evaporator, condenser and cascade condenser of two stage R404A-R508B cascade refrigeration system using Taguchi method. The operating parameters considered in present study includes (1) condensing temperature of high temperature cycle and low temperature cycle (2) evaporating temperature of low temperature cycle (3) degree of superheating in low temperature cycle (4) refrigerating effect. Heat transfer areas of three heat exchangers are studied with variation of above operating parameters and also optimum working levels of each operating parameter has been obtained for minimum heat transfer area of each heat exchanger using Taguchi method. The analysis using Taguchi method reveals that evaporating temperature of low temperature cycle and refrigerating effect contribute relatively largely on the area of evaporator. Condenser area is mainly influenced by both condensing temperature of high temperature cycle and refrigerating effect. Area of cascade condenser is mainly affected by refrigerating effect and the effects of other operating parameters are minimal.

Keywords: cascade refrigeration system, Taguchi method, heat transfer area, ANOVA, optimal solution

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Authors: Orawan Vichiansan, J. Kraipoj, K.Phandech, P. Sirasaporn

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Generally, frozen shoulder will improve over time, although it may take a long time up to year. The symptoms of frozen shoulder present by pain around shoulder and consequently limit range of motions. The effect of frozen shoulder leads to limit activities daily living life and high medical care cost. Physiotherapy is well known treatment for frozen shoulder but there was no data about the treatment of physiotherapy in frozen shoulder and length of follow up. Thus the aim of this study was to investigate physiotherapy program for frozen shoulder on range of motion and length of follow up. A retrospective study design was conducted. 469 medical records of patients with frozen shoulder were reviewed. These frozen shoulders were treated at physiotherapy unit, department of Rehabilitation last 3 years (January, 2014- December, 2016). The data consist of range of motions and length of follow up was recorded. The medical record of 183 males and 286 females with average aged 57.82±12.32 years were reviewed in this study. There was a statistically significant increase in shoulder flexion [mean difference 30.24 with 95%CI were [24.37-36.12], shoulder abduction [mean difference 34.93 with 95%CI were 27.8-42.0], shoulder internal rotation [mean difference 17.25 with 95%CI were 12.55-21.95] and shoulder external rotation [mean difference 17.71 with 95%CI were [13.07-22.36] respectively. In addition, the length of follow up averaged 84 days. In summary, the retrospective study show physiotherapy program likely to be benefit for patients with frozen shoulder in term of range of motion and short length of follow up.

Keywords: frozen shoulder, physiotherapy, range of motions, length of follow up

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Authors: F. S. Alavi

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In this study, MATLAB engineering software was used in order to model an industrial Ambient Air Vaporizer (AAV), considering combined convection and conduction heat transfers from the fins and the tube. The developed theoretical model was then used to investigate the effects of various design factors such as gas flow rate, ambient air temperature, fin thickness and etc. on total vaporizer ‘s length required. Cryogenic liquid nitrogen was selected as an input fluid, in all cases. According to the results, increasing the inlet fluid flow rate has direct linear effect on the total required length of vaporizer. Vaporizer’s required length decreases by increasing the size of fin radius or size of fin thickness. The dependency of vaporizer’s length on fin thickness’ size reduces at higher values of thickness and gradually converge to zero. For low flow rates, internal convection heat transfer coefficient depends directly on gas flow rate but it becomes constant, independent on flow rate after a specific value. As the ambient air temperature increases, the external heat transfer coefficient also increases and the total required length of vaporizer decreases.

Keywords: heat exchanger, modeling, heat transfer, design

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Authors: Sajjad Seifoori

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Impact behavior of striker on graphene sheet and carbon nanotube is investigated based on molecular dynamics (MD) simulations. A MD simulation is conducted to obtain the maximum dynamic deflections of a square and rectangular single-layered graphene sheets (SLGSs) with various values of side-length and striker parameter. Effect of (i) chirality, (ii) graphene side-length and nanotube length, (iii) striker mass on the maximum dynamic deflections of graphene and nanotube are investigated. The effect of different types of boundary condition on the maximum dynamic deflections is studied for zigzag and armchair SWCNTs with various aspect ratios (Length/Diameter).

Keywords: impact, molecular dynamic, graphene, spring mass

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Authors: Dhruveshi B. Rana, Nirav P. Vaghela, Jigar N. Mehta

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Objective: To assess the relationships among age, gender, anthropometrics and dynamic balance in 5 to 12 years of children in Anand city. Method: Cross-sectional study was conducted. 150 school going children of 5-12 (75-girls, 75-boys) years were recruited from the school of the Anand city-Shivam English Medium school, Veer Vithalbhai Patel school, Adarsh Primary school. Height, weight, arm length, and foot length were measured in 150 children of 5 to 12 years. Dynamic balance was assessed using Time Up and Go Test, Functional Reach Test, Pediatric Balance Scale. Results: Positive relationship (r = 0.58 and r= 0.77) were found between increasing age and FRT and PBS scores. A negative relationship (r = - 0.46) was observed between age of boys and TUG test. Significant gender by age group difference was observed in FRT. Arm length and height has the strongest influence on FRT, and age, height, foot length; and arm length has the strongest influence on PBS. Conclusions: Age and arm length have the strongest relationship with the dynamic balance (FRT, PBS). Dynamic balance ability is directly related to the age. It helps the pediatric therapists in selecting dynamic balance test according to the age.

Keywords: age, gender, anthropometric, dynamic balance

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Authors: Vashti Carissa

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The main objective of this study is to examine whether the life-cycle theory of dividends could explain the determinant of an optimal dividend policy in Indonesia. The sample that was used consists of 1,420 non-financial and non-trade, services, investment firms listed in Indonesian Stock Exchange during the period of 2005-2014. According to this finding using logistic regression, firm life-cycle measured by retained earnings as a proportion of total equity (RETE) significantly has a positive effect on the propensity of a firm pays dividend. The higher company’s earned surplus portion in its capital structure could reflect firm maturity level which will increase the likelihood of dividend payment in mature firms. This result provides an additional empirical evidence about the existence of life-cycle theory of dividends for dividend payout phenomenon in Indonesia. It can be known that dividends tend to be paid by mature firms while retention is more dominating in growth firms. From the testing results, it can also be known that majority of sample firms are being in the growth phase which proves the fact about infrequent dividend distribution in Indonesia during the ten years observation period.

Keywords: dividend, dividend policy, life-cycle theory of dividends, mix of earned and contributed capital

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Authors: Rajapaksha Gedara Prasad Tharanga Jayasooriya, Matharage Gayani Dilshara, Yung Hyun Choi, Gi-Young Kim

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Camptothecin (CPT) is a quinolone alkaloid which inhibits DNA topoisomerase I that induces cytotoxicity in a variety of cancer cell lines. We previously showed that CPT effectively inhibited invasion of prostate cancer cells and also combined treatment with subtoxic doses of CPT and TNF-related apoptosis-inducing ligand (TRAIL) potentially enhanced apoptosis in a caspase-dependent manner in hepatoma cancer cells. Here, we found that treatment with CPT caused an irreversible cell cycle arrest in the G2/M phase. CPT-induced cell cycle arrest was associated with a decrease in protein levels of cell division cycle 25C (Cdc25C) and increased the level of cyclin B and p21. The CPT-induced decrease in Cdc25C was blocked in the presence of proteasome inhibitor MG132, thus reversed the cell cycle arrest. In addition to that treatment of CPT-increased phosphorylation of Cdc25C was the resulted of activation of checkpoint kinase 2 (Chk2), which was associated with phosphorylation of ataxia telangiectasia-mutated. Interestingly CPT induced G2/M phase of the cell cycle arrest is reactive oxygen species (ROS) dependent where ROS inhibitors NAC and GSH reversed the CPT-induced cell cycle arrest. These results further confirm by using transient knockdown of nuclear factor-erythroid 2-related factor 2 (Nrf2) since it regulates the production of ROS. Our data reveal that treatment of siNrf2 increased the ROS level as well as further increased the CPT induce G2/M phase cell cycle arrest. Our data also indicate CPT-enhanced cell cycle arrest through the extracellular signal-regulated kinase (ERK) and the c-Jun N-terminal kinase (JNK) pathway. Inhibitors of ERK and JNK more decreased the Cdc25C expression and protein expression of p21 and cyclin B. These findings indicate that Chk2-mediated phosphorylation of Cdc25C plays a major role in G2/M arrest by CPT.

Keywords: camptothecin, cell cycle, checkpoint kinase 2, nuclear factor-erythroid 2-related factor 2, reactive oxygen species

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Authors: Lubena Achmad, Herman Kristanto, Julian Dewantiningrum

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Background: The Bishop score is a standard method used to predict the success of induction. This examination tends to be subjective with high inter and intraobserver variability, so it was presumed to have a low predictive value in terms of the outcome of labor induction. Cervical length measurement using transvaginal ultrasound is considered to be more objective to assess the cervical length. Meanwhile, this examination is not a complicated procedure and less invasive than vaginal touché. Objective: To compare transvaginal ultrasound and Bishop score in predicting successful induction. Methods: This study was a prospective cohort study. One hundred and twenty women with singleton pregnancies undergoing induction of labor at 37 – 42 weeks and met inclusion and exclusion criteria were enrolled in this study. Cervical assessment by both transvaginal ultrasound and Bishop score were conducted prior induction. The success of labor induction was defined as an ability to achieve active phase ≤ 12 hours after induction. To figure out the best cut-off point of cervical length and Bishop score, receiver operating characteristic (ROC) curves were plotted. Logistic regression analysis was used to determine which factors best-predicted induction success. Results: This study showed significant differences in terms of age, premature rupture of the membrane, the Bishop score, cervical length and funneling as significant predictors of successful induction. Using ROC curves found that the best cut-off point for prediction of successful induction was 25.45 mm for cervical length and 3 for Bishop score. Logistic regression was performed and showed only premature rupture of membranes and cervical length ≤ 25.45 that significantly predicted the success of labor induction. By excluding premature rupture of the membrane as the indication of induction, cervical length less than 25.3 mm was a better predictor of successful induction. Conclusion: Compared to Bishop score, cervical length using transvaginal ultrasound was a better predictor of successful induction.

Keywords: Bishop Score, cervical length, induction, successful induction, transvaginal sonography

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Authors: Mahdi Sadeghian, Mahmoud Hassanlourad, Alireza Ardakani, Reza Dinarvand

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In this research, the behavior of monopiles, under lateral loads, was investigated with vertical and oblique piles by Finite Element Method. In engineering practice when soil-pile interaction comes to the picture some simplifications are applied to reduce the design time. As a simplified replacement of soil and pile interaction analysis, pile could be replaced by a column. The height of the column would be equal to the free length of the pile plus a portion of the embedded length of it. One of the important factors studied in this study was that columns with an equivalent length (free length plus a part of buried depth) could be used instead of soil and pile modeling. The results of the analysis show that the more internal friction angle of the soil increases, the more the bearing capacity of the soil is achieved. This additional length is 6 to 11 times of the pile diameter in dense soil although in loose sandy soil this range might increase.

Keywords: Depth of fixity, Lateral bearing capacity, Oblique pile, Pile group, Soil-structure interaction

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Authors: Matthew J. Emes, Azadeh Jafari, Maziar Arjomandi

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Velocity fluctuations of shear-generated turbulence are largest in the atmospheric surface layer (ASL) of nominal 100 m depth, which can lead to dynamic effects such as galloping and flutter on small physical structures on the ground when the turbulence length scales and characteristic length of the physical structure are the same order of magnitude. Turbulence length scales are a measure of the average sizes of the energy-containing eddies that are widely estimated using two-point cross-correlation analysis to convert the temporal lag to a separation distance using Taylor’s hypothesis that the convection velocity is equal to the mean velocity at the corresponding height. Profiles of turbulence length scales in the neutrally-stratified ASL, as predicted by Monin-Obukhov similarity theory in Engineering Sciences Data Unit (ESDU) 85020 for single-point data and ESDU 86010 for two-point correlations, are largely dependent on the aerodynamic roughness length. Field measurements have shown that longitudinal turbulence length scales show significant regional variation, whereas length scales of the vertical component show consistent Obukhov scaling from site to site because of the absence of low-frequency components. Hence, the objective of this experimental study is to compare the similarity theory relationships between the turbulence length scales and aerodynamic roughness length with those calculated using the autocorrelations and cross-correlations of field measurement velocity data at two sites: the Surface Layer Turbulence and Environmental Science Test (SLTEST) facility in a desert ASL in Dugway, Utah, USA and the Commonwealth Scientific and Industrial Research Organisation (CSIRO) wind tower in a rural ASL in Jemalong, NSW, Australia. The results indicate that the longitudinal turbulence length scales increase with increasing aerodynamic roughness length, as opposed to the relationships derived by similarity theory correlations in ESDU models. However, the ratio of the turbulence length scales in the lateral and vertical directions to the longitudinal length scales is relatively independent of surface roughness, showing consistent inner-scaling between the two sites and the ESDU correlations. Further, the diurnal variation of wind velocity due to changes in atmospheric stability conditions has a significant effect on the turbulence structure of the energy-containing eddies in the lower ASL.

Keywords: aerodynamic roughness length, atmospheric surface layer, similarity theory, turbulence length scales

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Authors: Mohammed Alenezy

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The function of cardiac motion can be used as an indicator of the heart abnormality by evaluating longitudinal, circumferential, and Radial Strain of the left ventricle. In this paper, the Radial Strain and SR is studied using tagged MRI (tMRI) data during the cardiac cycle on the mid-ventricle level of the left ventricle. Materials and methods: The short-axis view of the left ventricle of five healthy human (three males and two females) and four healthy male rats were imaged using tagged magnetic resonance imaging (tMRI) technique covering the whole cardiac cycle on the mid-ventricle level. Images were processed using Image J software to calculate the left ventricle wall Radial Strain and radial SR. The left ventricle Radial Strain and radial SR were calculated at the mid-ventricular level during the cardiac cycle. The peak Radial Strain for the human and rat heart was 40.7±1.44, and 46.8±0.68 respectively, and it occurs at 40% of the cardiac cycle for both human and rat heart. The peak diastolic and systolic radial SR for human heart was -1.78 s-1 ± 0.02 s-1 and 1.10±0.08 s-1 respectively, while for rat heart it was -5.16± 0.23s-1 and 4.25±0.02 s-1 respectively. Conclusion: This results show the ability of the tMRI data to characterize the cardiac motion during the cardiac cycle including diastolic and systolic phases which can be used as an indicator of the cardiac dysfunction by estimating the left ventricle Radial Strain and radial SR at different locations of the cardiac tissue. This study approves the validity of the tagged MRI data to describe accurately the cardiac radial motion.

Keywords: left ventricle, radial strain, tagged MRI, cardiac cycle

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Authors: Joe Hachem, Marianne Cuif-Sjostrand, Thierry Schuhler, Dominique Orhon, Assaad Zoughaib

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The exhaust gas recirculation, EGR, implementation on gas turbines is increasingly gaining the attention of many researchers. This emerging technology presents many advantages, such as lowering the NOx emissions and facilitating post-combustion carbon capture as the carbon dioxide concentration in the cycle increases. As interesting as this technology may seem, the gas turbine, or its thermodynamic equivalent, the Brayton cycle, shows an intrinsic efficiency decrease with increasing EGR rate. In this paper, a thermodynamic model is presented to show the cycle efficiency decrease with EGR, alternative values of design parameters of both the pressure ratio (PR) and the turbine inlet temperature (TIT) are then proposed to optimize the cycle efficiency with different EGR rates. Results show that depending on the given EGR rate, both the design PR & TIT should be increased to compensate for the deficit in efficiency.

Keywords: gas turbines, exhaust gas recirculation, design parameters optimization, thermodynamic approach

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Authors: S. Sabzchi Asl, N. Tahouni, M. H. Panjeshahi

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Benchmarking of a process with respect to energy consumption, without accomplishing a full retrofit study, can save both engineering time and money. In order to achieve this goal, the first step is to develop a conceptual-mathematical model that can easily be applied to a group of similar processes. In this research, we have aimed to identify a set of key parameters for the model which is supposed to be used for benchmarking of combined cycle power plants. For this purpose, three similar combined cycle power plants were studied. The results showed that ambient temperature, pressure and relative humidity, number of HRSG evaporator pressure levels and relative power in part load operation are the main key parameters. Also, the relationships between these parameters and produced power (by gas/ steam turbine), gas turbine and plant efficiency, temperature and mass flow rate of the stack flue gas were investigated.

Keywords: combined cycle power plant, energy benchmarking, modelling, retrofit

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Authors: Saeedeh Bakhtiari, Johannes Depessemier, Stijn Hertelé, Wim De Waele

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High cycle fatigue comprising up to 10⁷ load cycles has been the subject of many studies, and the behavior of many materials was recorded adequately in this regime. However, many applications involve larger numbers of load cycles during the lifetime of machine components. In this ultra-high cycle regime, other failure mechanisms play, and the concept of a fatigue endurance limit (assumed for materials such as steel) is often an oversimplification of reality. When machine component design demands a high geometrical complexity, cast iron grades become interesting candidate materials. Grey cast iron is known for its low cost, high compressive strength, and good damping properties. However, the ultra-high cycle fatigue behavior of cast iron is poorly documented. The current work focuses on the ultra-high cycle fatigue behavior of EN-GJL-250 (GG25) grey cast iron by developing an ultrasonic (20 kHz) fatigue testing system. Moreover, the testing machine is instrumented to measure the temperature and the displacement of  the specimen, and to control the temperature. The high resonance frequency allowed to assess the  behavior of the cast iron of interest within a matter of days for ultra-high numbers of cycles, and repeat the tests to quantify the natural scatter in fatigue resistance.

Keywords: GG25, cast iron, ultra-high cycle fatigue, ultrasonic test

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Authors: Nabil Beroual, Tewfik Sari

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We consider the Gause-type predator-prey system in the case where the response function is not smooth at the origin. We discuss the conditions under which this system has exactly one stable limit cycle or has a positive stable equilibrium point, and we describe the basin of attraction of the stable limit cycle and the stable equilibrium point, respectively. Our results correct previous results of the existing literature.

Keywords: predator-prey model, response function, singularity, basin of attraction, limit cycle

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Authors: Daniel Tochwin

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Continuous improvement is an essential part of effective process performance management. In order to achieve continuous quality improvement, each organization must use the appropriate selection of tools and techniques. The basic condition for success is a proper understanding of the business need faced by the company and the selection of appropriate methods to improve a given production process. The main aim of this article is to analyze the methods of conduct which are popular in practice when implementing process improvements and then to determine whether the tested methods include repetitive systematics of the approach, i.e., a similar sequence of the same or similar actions. Based on an extensive literature review, 4 methods of continuous improvement of production processes were selected: A3 report, Gemba Kaizen, PDCA cycle, and Deming cycle. The research shows that all frequently used improvement methods are generally based on the PDCA cycle, and the differences are due to "(re)interpretation" and the need to adapt the continuous improvement approach to the specific business process. The research shows that all the frequently used improvement methods are generally based on the PDCA cycle, and the differences are due to "(re) interpretation" and the need to adapt the continuous improvement approach to the specific business process.

Keywords: continuous improvement, lean methods, process improvement, PDCA

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Authors: Sayali Vyas, Atharva Desai, Shreyas Badave, Apurv Kulkarni, B. Rajiv

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The Failure Modes and Effect Analysis (FMEA) is an efficient evaluation technique to identify potential failures in products, processes, and services. FMEA is designed to identify and prioritize failure modes. It proves to be a useful method for identifying and correcting possible failures at its earliest possible level so that one can avoid consequences of poor performance. In this paper, FMEA tool is used in detection of failures of various components of heat exchanger cycle and to identify critical failures of the components which may hamper the system’s performance. Further, a detailed Pareto analysis is done to find out the most critical components of the cycle, the causes of its failures, and possible recommended actions. This paper can be used as a checklist which will help in maintainability of the system.

Keywords: FMEA, heat exchanger cycle, Ishikawa diagram, pareto analysis, RPN (Risk Priority Number)

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Authors: Qazi Salman Khalid, Muhammad Khalid, Shahid Maqsood

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This paper presents a solution for optimizing the cycle time in an assembly line with human-robot collaboration and diverse operators. A genetic algorithm with tailored parameters is used to address the assembly line balancing problem in the automobile sector. A mathematical model is developed, depicting the problem. Currently, the firm runs on the largest candidate rule; however, it causes a lag in orders, which ultimately gets penalized. The results of the study show that the proposed GA is effective in providing efficient solutions and that the cycle time has significantly impacted productivity.

Keywords: line balancing, cycle time, genetic algorithm, productivity

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Authors: Rahim Ada, Zamari Temory, Hasan Dalgic

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Germination and seedling responses of seven safflower seed genotypes (Dinçer, Remzibey, Black Sun2 cultivars and A19, F4, I1, J19 lines) to different salinity concentrations (0, 5, 10, and 20 g l-1) and temperatures (10 and 20 oC) evaluated in Completely Randomized Factorial Designs in Department of Field Crops of Selcuk University, Konya, Turkey. Seeds in the control (distilled water) had at 10 and 20 oC the highest germination percentage (93.88 and 94.32 %), shoot length (4.60 and 8.72 cm), root length (4.27 and 6.54 cm), shoot dry weight (22.37 mg and 25.99 mg), and root dry weight (2.22 and 2.47 mg). As the salt concentration increased, values of all characters were decreased. In this experiment, in 20 g l-1 salt concentration found germination percentage (21.28 and 26.66 %), shoot (1.32 and 1.35 cm) and root length (1.04 and 1.10 cm), shoot (8.05 mg and 7.49 mg) and root dry weight (0.83 and 0.98 mg) at 10, and 20 oC.

Keywords: safflower, NaCl, temperature, shoot and root length, salt concentration

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Authors: Isobel Hambleton, Mark Carrington

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Trypanosoma brucei, the causal agent of a range of diseases in humans and livestock, evades the mammalian immune system through a population survival strategy based on the expression of a series of antigenically distinct variant surface glycoproteins (VSGs). RNAi mediated knockdown of the active VSG gene triggers a precytokinesis cell cycle arrest. To determine whether this phenotype is the result of reduced VSG transcript or depleted VSG protein, we used morpholino antisense oligonucleotides to block translation of VSG mRNA. The same precytokinesis cell cycle arrest was observed, suggesting that VSG protein abundance is monitored closely throughout the cell cycle. An inducible expression system has been developed to test various GPI-anchored proteins for their ability to rescue this cell cycle arrest. This system has been used to demonstrate that wild-type VSG expressed from a T7 promoter rescues this phenotype. This indicates that VSG expression from one of the specialised bloodstream expression sites (BES) is not essential for cell division. The same approach has been used to define the minimum essential features of a VSG necessary for function.

Keywords: bloodstream expression site, morpholino, precytokinesis cell cycle arrest, variant surface glycoprotein

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Authors: Saria Abed, Tahar Khir, Ammar Ben Brahim

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A thermo-exergy optimization of a gas turbine cycle with two different regenerator designs is established. A comparison was made between the performance of the two regenerators and their roles in improving the cycle efficiencies. The effect of operational parameters (the pressure ratio of the compressor, the ambient temperature, excess of air, geometric parameters of the regenerators, etc.) on thermal efficiencies, the exergy efficiencies, and irreversibilities were studied using thermal balances and quantitative exegetic equilibrium for each component and for the whole system. The results are given graphically by using the EES software, and an appropriate discussion and conclusion was made.

Keywords: exergy efficiency, gas turbine, heat transfer, irreversibility, optimization, regenerator, thermal efficiency

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Authors: Hongmei Gu, Shaobo Liang, Richard Bergman

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With current worldwide trend in designs to have net-zero emission buildings to mitigate climate change, widespread use of mass timber products, such as Cross Laminated Timber (CLT), or Nail Laminated Timber (NLT) or Dowel Laminated Timber (DLT) in buildings have been proposed as one approach in reducing Greenhouse Gas (GHG) emissions. Consequentially, mass timber building designs are being adopted more and more by architectures in North America, especially for mid- to high-rise buildings where concrete and steel buildings are currently prevalent, but traditional light-frame wood buildings are not. Wood buildings and their associated wood products have tended to have lower environmental impacts than competing energy-intensive materials. It is common practice to conduct life cycle assessments (LCAs) and life cycle cost analyses on buildings with traditional structural materials like concrete and steel in the building design process. Mass timber buildings with lower environmental impacts, especially GHG emissions, can contribute to the Net Zero-emission goal for the world-building sector. However, the economic impacts from CLT mass timber buildings still vary from the life-cycle cost perspective and environmental trade-offs associated with GHG emissions. This paper quantified the Total Life Cycle Cost and cradle-to-grave GHG emissions of a pre-designed CLT mass timber building and compared it to a functionally-equivalent concrete building. The Total life cycle Eco-cost-efficiency is defined in this study and calculated to discuss the trade-offs for the net-zero emission buildings in a holistic view for both environmental and economic impacts. Mass timber used in buildings for the United States is targeted to the materials from the nation’s sustainable managed forest in order to benefit both national and global environments and economies.

Keywords: GHG, economic impact, eco-cost-efficiency, total life-cycle costs

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Authors: M. Z. Abdul Rofiq Badril Rizal

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This research is aimed to know the improvement of students’ English writing skill by using brainstorming technique. The technique used in writing is able to help the students’ difficulties in generating ideas and to lead the students to arrange the ideas well as well as to focus on the topic developed in writing. The research method used is classroom action research. The data sources of the research are an English teacher who acts as an observer and the students of class X.MIA5 consist of 35 students. The test result and observation are collected as the data in this research. Based on the research result in cycle one, the percentage of students who reach minimum accomplishment criteria (MAC) is 76.31%. It shows that the cycle must be continued to cycle two because the aim of the research has not accomplished, all of the students’ scores have not reached MAC yet. After continuing the research to cycle two and the weaknesses are improved, the process of teaching and learning runs better. At the test which is conducted in the end of learning process in cycle two, all of the students reach the minimum score and above 76 based on the minimum accomplishment criteria. It means the research has been successful and the percentage of students who reach minimum accomplishment criteria is 100%. Therefore, the writer concludes that brainstorming technique is able to improve the students’ English writing skill at the tenth grade of SMAN 2 Jember.

Keywords: brainstorming technique, improving, writing skill, knowledge and innovation engineering

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Authors: Adeyemi, Samuel Olusegun

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Biometrics and dietary habit of Citharinus citharus in the lower Niger River area of kogi state were studied between October and December, 2010. A total of 120 fish sampled were used for the study. The total length, standard length and weight were taken for each fish sample for the estimations of length-weight relationship using the formula W = aLb and transformed to Log W = Log a + b Log L. Stomach contents were analyzed by frequency of occurrence method. The standard length of males, females and combined sexes ranged between 6.8 - 16.5, 7.3 – 14.3 cm, 6.8 – 74.2 (cm) respectively, with b – values of 3.0963, 3.174 and 3.1382. The condition factor ranged from 2.04 – 2.80, 1.88 – 2.86 and 1.88 – 2.86 respectively. The food and feeding habits shows that the fish feeds mainly sand grain (25.83%), mud (24.16%), plant parts (12.50%), insect part (2.50%), algae (12.50%) and unidentified items (5.00%). C. citharus in the lower Niger area of kogi state could be termed to an omnivore. River Niger could be said to be suitable for growth and survival of the fish species C. citharus.

Keywords: length-weight, sexes, stomach content, feeding habits, plant materials

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Authors: Monireh Azimi, Mohammad Reza Toroghinejad, Leo A. I. Kestens

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The role of different metallic and intermetallic reinforcements on the microstructure and the associated mechanical response of a composite is of crucial importance. To investigate this issue, a multiphase metal-intermetallic composite was in-situ fabricated through reactive annealing and accumulative roll bonding (ARB) processes. EBSD results indicated that the lamellar grain structure of the Al matrix after the first cycle has evolved with increasing strain to a mixed structure consisting of equiaxed and lamellar grains, whereby the steady-state did not occur after the 3rd (last) cycle—applying a strain of 6.1 in the Al phase, the length and thickness of the grains reduced by 92.2% and 97.3%, respectively, compared to the annealed state. Intermetallic phases together with the metallic reinforcement of Ni influence grain fragmentation of the Al matrix and give rise to a specific texture evolution by creating heterogeneity in the strain and flow patterns. Mechanical properties of the multiphase composite demonstrated the yield and ultimate tensile strengths of 217.9 MPa and 340.1 MPa, respectively, compared to 48.7 MPa and 55.4 MPa in the metal-intermetallic laminated (MIL) sandwich before applying the ARB process, which corresponds to an increase of 347% and 514% of yield and tensile strength, respectively.

Keywords: accumulative roll bonding, mechanical properties, metal-intermetallic composite, severe plastic deformation, texture

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Authors: Yahya Maeni

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It is well established that amblyopic patients have a reduced reading performance and oculomotor deficits. Word length has a significant impact on reading performance and eye movement behaviour during reading. As there no previous attempts to assess whether amblyopic eyes would be affected by word length while reading. This study aims to assess the effect of word length on amblyopic eye movement behaviour during reading including fixation duration, number of fixation and gaze duration. 21 adults with amblyopia and 21 age-matched controls participated in the study (age ± SD) (23.80 ± 4.66) for amblyopes and (24.20 ± 3.58) for Controls. Eye movement was recorded during reading binocularly using Eyelink 1000. Study was designed as 2 x 2 (amblyopia vs. control) x 2 lengths (4 letters, and 8 letters). Compared to controls, the amblyopic participants report significant longer duration of fixation, higher number of fixation and longer gaze duration for short words with far higher significant difference for long words. It could be concluded that eye movement in amblyopia during reading might be accounted for by the length of a word within a text and this could possible explanation of reduced reading performance among amblyopes. By understanding the effect of word length on amblyopia will shed light on reading deficits in amblyopia and help to determine the reading needs of amplyopes in educational and clinical settings.

Keywords: amblyopia, eye movement, reading, fixation

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Authors: Jing (Claire) LI

Abstract:

The topic of corporate social responsibility (CSR) is significant for pharmaceutical companies in China at this current stage. This is because, as a rapid growth industry in China in recent years, the pharmaceutical industry in China has been undergone continuous and terrible incidents relating to CSR. However, there is limited research and practice of CSR in Chinese pharmaceutical companies. Also, there is an urgent call for more research in an international context to understand the implications of corporate life cycle on CSR performance. To respond to the research need and research call, this study examines the relationship between corporate life cycle and CSR performance of Chinese listed companies in pharmaceutical industry. This research studies Chinese listed companies in pharmaceutical industry for the period of 2010-2017, where the data is available in database. Following the literature, this study divides CSR performance with regards to CSR dimensions, including shareholders, creditors, employees, customers, suppliers, the government, and the society. This study uses CSR scores of HEXUN database and financial measures of these CSR dimensions to measure the CSR performance. This study performed regression analysis to examine the relationship between corporate life cycle stages and CSR performance with regards to CSR dimensions for pharmaceutical listed companies in China. Using cash flow pattern as proxy of corporate life cycle to classify corporate life cycle stages, this study found that most (least) pharmaceutical companies in China are in maturity (decline) stage. This study found that CSR performance for most dimensions are highest (lowest) in maturity (decline) stage as well. Among these CSR dimensions, performing responsibilities for shareholder is the most important among all CSR responsibilities for pharmaceutical companies. This study is the first to provide important empirical evidence from Chinese pharmaceutical industry on the association between life cycle and CSR performance, supporting that corporate life cycle is a key factor in CSR performance. The study expands corporate life cycle and CSR literatures and has both empirical and theoretical contributions to the literature. From perspective of empirical contributions, the findings contribute to the argument that whether there is a relationship between CSR performance and various corporate life cycle stages in the literature. This study also provides empirical evidence that companies in different corporate life cycles have difference in CSR performance. From perspective of theoretical contributions, this study relates CSR and stakeholders to corporate life cycle stages and complements the corporate life cycle and CSR literature. This study has important implications for managers and policy makers. First, the results will be helpful for managers to have an understanding in the essence of CSR, and their company’s current and future CSR focus over corporate life cycle. This study provides a reference for their actions and may help them make more wise resources allocation decisions of CSR investment. Second, policy makers (in the government, stock exchanges, and securities commission) may consider corporate life cycle as an important factor in formulating future regulations for companies. Future research can explore the "process-based" differences in CSR performance and more industries.

Keywords: China, corporate life cycle, corporate social responsibility, pharmaceutical industry

Procedia PDF Downloads 77

Authors: Mehdi Soltani Howyzeh, Neda Kardoni, Mani Mojadam

Abstract:

To evaluate the vigor of wheat seeds and stress of premature aging effects on germination percentage, root length and shoot length of five wheat cultivars that include Vynak, Karkheh, Chamran, Star and Kavir which underwent a period of zero, two, three, four days in terms of premature aging with 41 °C temperature and 100% relative humidity. Seed germination percentage, root length and shoot length in these conditions were measured. This experiment was conducted as a factorial completely randomized design with four replications in laboratory conditions. The results showed that each of aging treatments used in this experiment can be used to detect differences in vigor of wheat varieties. Wheat cultivars illustrated significant differences in germination percentage, root length and shoot length in terms of premature aging. The wheat cultivars; Astar and Vynak had maximum germination percentage and Karkheh, respectively Kavir and Chamran had lowest percentage of seed germination. Reactions of root and shoot length of wheat cultivars was also different. The results showed that the seeds with a stronger vigor affected less in premature aging condition and the difference between the percentage of seed germination under normal conditions and stress was significant and the seeds with the weaker vigor were more sensitive to the premature aging stress and the premature aging had more severe negative impact on seed vigor.

Keywords: wheat cultivars, seed vigor, premature aging effects, germination

Procedia PDF Downloads 304

Authors: Venkat S. Somayajula

Abstract:

Ground surface temperature history prediction model plays a vital role in determining standards for international nuclear waste management. International standards for borehole based nuclear waste disposal require paleoclimate cycle predictions on scale of a million forward years for the place of waste disposal. This research focuses on developing a paleoclimate cycle prediction model using Bayesian long-short term memory (LSTM) neural architecture operated on accumulated borehole temperature history data. Bayesian models have been previously used for paleoclimate cycle prediction based on Monte-Carlo weight method, but due to limitations pertaining model coupling with certain other prediction networks, Bayesian models in past couldn’t accommodate prediction cycle’s over 1000 years. LSTM has provided frontier to couple developed models with other prediction networks with ease. Paleoclimate cycle developed using this process will be trained on existing borehole data and then will be coupled to surface temperature history prediction networks which give endpoints for backpropagation of LSTM network and optimize the cycle of prediction for larger prediction time scales. Trained LSTM will be tested on past data for validation and then propagated for forward prediction of temperatures at borehole locations. This research will be beneficial for study pertaining to nuclear waste management, anthropological cycle predictions and geophysical features

Keywords: Bayesian long-short term memory neural network, borehole temperature, ground surface temperature history, paleoclimate cycle

Procedia PDF Downloads 100

Authors: Tony Rizk

Abstract:

Recent material advances and cost efficiencies are transforming the housing industry away from traditional lumber and gypsum material to alternate fiberboard material that is workable and resistant to fire, mold, and pest infestation. The use of these materials may add to the initial cost of construction. However, the life cycle (cradle to grave) cost of houses using these construction materials and methods are lower than the life cycle costs using traditional housing construction materials and methods. This paper will present four (4) case studies of sustainable house projects. Each project was designed and constructed using earthen-based, sustainable fiberboard material that is resistant to fire, mold, and infestation and fabricated at a very low material calorific value. These house projects have a living space ranging from 625 sq. ft. for an accessory dwelling unit and up to 3,200 sq. ft. 1-story and 2-story homes. For each case study, we will present the house engineering design and construction method, the initial construction costs, a summary of the life cycle costs, and a comparison to the life cycle cost of traditional housing available in the literature.

Keywords: residential housing, sustainable housing, life cycle cost, fire resistance, mold, infestation resistance

Procedia PDF Downloads 94