Search results for: higher order ODEs.
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7618

Search results for: higher order ODEs.

6418 Study on the Evaluation of the Chaotic Cipher System Using the Improved Volterra Filters and the RBFN Mapping

Authors: Hirotaka Watanabe, Takaaki Kondo, Daiki Yoshida, Ariyoshi Nakayama, Taichi Sato, Shuhei Kuriyama, Hiroyuki Kamata

Abstract:

In this paper, we propose a chaotic cipher system consisting of Improved Volterra Filters and the mapping that is created from the actual voice by using Radial Basis Function Network. In order to achieve a practical system, the system supposes to use the digital communication line, such as the Internet, to maintain the parameter matching between the transmitter and receiver sides. Therefore, in order to withstand the attack from outside, it is necessary that complicate the internal state and improve the sensitivity coefficient. In this paper, we validate the robustness of proposed method from three perspectives of "Chaotic properties", "Randomness", "Coefficient sensitivity".

Keywords: Chaos cipher, 16-bit-length fixed point arithmetic, Volterra filter, Seacret communications, RBF Network

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6417 Effects of Gratitude Practice on Relationship Satisfaction and the Role of Perceived Superiority

Authors: Anomi Bearden, Brooke Goodyear, Alicia Khan

Abstract:

This repeated-measures experiment explored the effects of six weeks of gratitude practice on college students (N = 67) on relationship satisfaction and perceived superiority. Replicating previous research on gratitude practice, it was hypothesized that after consistent gratitude practice, participants in the experimental group (n = 32) would feel increased levels of relationship satisfaction compared to the control group (n = 35). Of particular interest was whether the level of perceived superiority would moderate the effect of gratitude practice on relationship satisfaction. The gratitude group evidenced significantly higher appreciation and marginally higher relationship satisfaction at post-test than the control group (both groups being equal at pre-test). Significant enhancements in gratitude, satisfaction, and feeling both appreciative and appreciated were found in the gratitude group, as well as significant enhancements in gratitude, satisfaction, and feeling appreciated in the control group. Appreciation for one’s partner was the only measure that improved in the gratitude group and not the control group from pre-test to post-test. Perceived superiority did not change significantly from pre-test to post-test in either group, supporting the prevalence and stability of this bias within people’s overall perceptions of their relationships.

Keywords: Gratitude, relationship satisfaction, perceived superiority, partner appreciation.

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6416 Analysis of One Dimensional Advection Diffusion Model Using Finite Difference Method

Authors: Vijay Kumar Kukreja, Ravneet Kaur

Abstract:

In this paper, one dimensional advection diffusion model is analyzed using finite difference method based on Crank-Nicolson scheme. A practical problem of filter cake washing of chemical engineering is analyzed. The model is converted into dimensionless form. For the grid Ω × ω = [0, 1] × [0, T], the Crank-Nicolson spatial derivative scheme is used in space domain and forward difference scheme is used in time domain. The scheme is found to be unconditionally convergent, stable, first order accurate in time and second order accurate in space domain. For a test problem, numerical results are compared with the analytical ones for different values of parameter.

Keywords: Consistency, Crank-Nicolson scheme, Gerschgorin circle, Lax-Richtmyer theorem, Peclet number, stability.

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6415 Model-Based Small Area Estimation with Application to Unemployment Estimates

Authors: Hichem Omrani, Philippe Gerber, Patrick Bousch

Abstract:

The problem of Small Area Estimation (SAE) is complex because of various information sources and insufficient data. In this paper, an approach for SAE is presented for decision-making at national, regional and local level. We propose an Empirical Best Linear Unbiased Predictor (EBLUP) as an estimator in order to combine several information sources to evaluate various indicators. First, we present the urban audit project and its environmental, social and economic indicators. Secondly, we propose an approach for decision making in order to estimate indicators. An application is used to validate the theoretical proposal. Finally, a decision support system is presented based on open-source environment.

Keywords: Small area estimation, statistical method, sampling, empirical best linear unbiased predictor (EBLUP), decision-making.

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6414 Thermal Property of Multi-Walled-Carbon-Nanotube Reinforced Epoxy Composites

Authors: Min Ye Koo, Gyo Woo Lee

Abstract:

In this study, epoxy composite specimens reinforced with multi-walled carbon nanotube filler were fabricated using shear mixer and ultra-sonication processor. The mechanical and thermal properties of the fabricated specimens were measured and evaluated. From the electron microscope images and the results from the measurements of tensile strengths, the specimens having 0.6 wt% nanotube content show better dispersion and higher strength than those of the other specimens. The Young’s moduli of the specimens increased as the contents of the nanotube filler in the matrix were increased. The specimen having a 0.6 wt% nanotube filler content showed higher thermal conductivity than that of the other specimens. While, in the measurement of thermal expansion, specimens having 0.4 and 0.6 wt% filler contents showed a lower value of thermal expansion than that of the other specimens. On the basis of the measured and evaluated properties of the composites, we believe that the simple and time-saving fabrication process used in this study was sufficient to obtain improved properties of the specimens.

Keywords: Carbon Nanotube Filler, Epoxy Composite, Ultra-Sonication, Shear Mixer, Mechanical Property, Thermal Property.

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6413 Modelling a Hospital as a Queueing Network: Analysis for Improving Performance

Authors: Emad Alenany, M. Adel El-Baz

Abstract:

In this paper, the flow of different classes of patients into a hospital is modelled and analyzed by using the queueing network analyzer (QNA) algorithm and discrete event simulation. Input data for QNA are the rate and variability parameters of the arrival and service times in addition to the number of servers in each facility. Patient flows mostly match real flow for a hospital in Egypt. Based on the analysis of the waiting times, two approaches are suggested for improving performance: Separating patients into service groups, and adopting different service policies for sequencing patients through hospital units. The separation of a specific group of patients, with higher performance target, to be served separately from the rest of patients requiring lower performance target, requires the same capacity while improves performance for the selected group of patients with higher target. Besides, it is shown that adopting the shortest processing time and shortest remaining processing time service policies among other tested policies would results in, respectively, 11.47% and 13.75% reduction in average waiting time relative to first come first served policy.

Keywords: Queueing network, discrete-event simulation, health applications, SPT.

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6412 Comparative Studies on Interactions of Synthetic and Natural Compounds with Hen Egg-White Lysozyme

Authors: Seifollah Bahramikia

Abstract:

Amyloid aggregation of polypeptides is related to a growing number of pathologic states known as amyloid disorders. In recent years, blocking or reversing amyloid aggregation via the use of small compounds are considered as two useful approaches in hampering the development of these diseases. In this research, we have compared the ability of several manganese-salen derivatives, as synthetic compounds, and apigenin, as a natural flavonoid, to inhibit of hen egg-white lysozyme (HEWL) aggregation, as an in vitro model system. Different spectroscopic analyses such as Thioflavin T (ThT) and Anilinonaphthalene-8-sulfonic acid (ANS) fluorescence, Congo red (CR) absorbance along with transmission electron microscopy were used in this work to monitor the HEWL aggregation kinetic and inhibition. Our results demonstrated that both type of compounds were capable to prevent the formation of lysozyme amyloid aggregation in vitro. In addition, our data indicated that synthetic compounds had higher activity to inhibit of the β-sheet structures relative to natural compound. Regarding the higher antioxidant activities of the salen derivatives, it can be concluded that in addition to aromatic rings of each of the compounds, the potent antioxidant properties of salen derivatives contributes to lower lysozyme fibril accumulation.

Keywords: Aggregation, anti-amyloidogenic, apigenin, hen egg white lysozyme, salen derivatives.

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6411 Supporting Technology Transfer with Communities and Social Software Solutions

Authors: G. Schuh, S. Aghassi

Abstract:

In order to bridge the gap between research and industry, promoting technology and knowledge transfer becomes increasingly important. Especially small- and medium-sized enterprises, having only little R&D resources themselves, depend on external technology development activities for remaining innovative. Academia research on the other hand needs potential industrial partners, who are capable and willing to commercialize their technologies as most public funding programs require some sort of technology transfer or dissemination activities. Modern web technologies offer more and more “social” functionalities and open up new ways of user interaction. In the past years several technology transfer platforms were developed, making use of modern web technologies in order to enable and support technology transfer. In this paper we report on the results of a state-of-the art analyses of existing technology transfer platforms, point out their advantages and deficits and give a perspective to the development of an improved technology transfer platform.

Keywords: Knowledge transfer, social software, technology management, technology transfer.

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6410 The Modified Eigenface Method using Two Thresholds

Authors: Yan Ma, ShunBao Li

Abstract:

A new approach is adopted in this paper based on Turk and Pentland-s eigenface method. It was found that the probability density function of the distance between the projection vector of the input face image and the average projection vector of the subject in the face database, follows Rayleigh distribution. In order to decrease the false acceptance rate and increase the recognition rate, the input face image has been recognized using two thresholds including the acceptance threshold and the rejection threshold. We also find out that the value of two thresholds will be close to each other as number of trials increases. During the training, in order to reduce the number of trials, the projection vectors for each subject has been averaged. The recognition experiments using the proposed algorithm show that the recognition rate achieves to 92.875% whilst the average number of judgment is only 2.56 times.

Keywords: Eigenface, Face Recognition, Threshold, Rayleigh Distribution, Feature Extraction

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6409 An Advanced Stereo Vision Based Obstacle Detection with a Robust Shadow Removal Technique

Authors: Saeid Fazli, Hajar Mohammadi D., Payman Moallem

Abstract:

This paper presents a robust method to detect obstacles in stereo images using shadow removal technique and color information. Stereo vision based obstacle detection is an algorithm that aims to detect and compute obstacle depth using stereo matching and disparity map. The proposed advanced method is divided into three phases, the first phase is detecting obstacles and removing shadows, the second one is matching and the last phase is depth computing. We propose a robust method for detecting obstacles in stereo images using a shadow removal technique based on color information in HIS space, at the first phase. In this paper we use Normalized Cross Correlation (NCC) function matching with a 5 × 5 window and prepare an empty matching table τ and start growing disparity components by drawing a seed s from S which is computed using canny edge detector, and adding it to τ. In this way we achieve higher performance than the previous works [2,17]. A fast stereo matching algorithm is proposed that visits only a small fraction of disparity space in order to find a semi-dense disparity map. It works by growing from a small set of correspondence seeds. The obstacle identified in phase one which appears in the disparity map of phase two enters to the third phase of depth computing. Finally, experimental results are presented to show the effectiveness of the proposed method.

Keywords: obstacle detection, stereo vision, shadowremoval, color, stereo matching

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6408 Growth and Stomatal Responses of Bread Wheat Genotypes in Tolerance to Salt Stress

Authors: Afrasyab Rahnama, Kazem Poustini, Reza Tavakkol-Afshari, Afshin Tavakoli

Abstract:

Plant growth is affected by the osmotic stress as well as toxicity of salt in leaves. In order to study of salt stress effects on stomatal conductance and growth rate and relationship between them as wells osmotic and Na+-specific effects on these traits, four bread wheat genotypes differing in salt tolerance were selected. Salinity was applied when the leaf 4 was fully expanded. Sodium (Na+) concentrations in flag leaf blade at 3 salinity levels (0, 100 and 200 mM NaCl) were measured. Salt-tolerant genotypes showed higher stomatal conductance and growth rate compared to salt-sensitive ones. After 10 and 20 days exposure to salt, stomatal conductance and relative growth rate were reduced, but the reduction was greater in sensitive genotypes. Growth rate was reduced severely in the first period (1-10 days) of salt commencements and it was due to osmotic effect of salt not Na+ toxicity. In the second period (11-20 days) after salt treatment growth reduced only when salt accumulated to toxic concentrations in the leaves. A positive relationship between stomatal conductance and relative growth rate showed that stomatal conductance can be a reliable indicator of growth rate, and finally can be considered as a sensitive indicator of the osmotic stress. It seems 20 days after salinity, the major effect of salt, especially at low to moderate salinity levels on growth properties was due to the osmotic effect of salt, not to Na+-specific effects within the plant.

Keywords: Osmotic stress, relative growth rate, stomatal conductance, wheat.

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6407 Performance Verification of Seismic Design Codes for RC Frames

Authors: Payam Asadi, Ali Bakhshi

Abstract:

In this study, a frame work for verification of famous seismic codes is utilized. To verify the seismic codes performance, damage quantity of RC frames is compared with the target performance. Due to the randomness property of seismic design and earthquake loads excitation, in this paper, fragility curves are developed. These diagrams are utilized to evaluate performance level of structures which are designed by the seismic codes. These diagrams further illustrate the effect of load combination and reduction factors of codes on probability of damage exceedance. Two types of structures; very high important structures with high ductility and medium important structures with intermediate ductility are designed by different seismic codes. The Results reveal that usually lower damage ratio generate lower probability of exceedance. In addition, the findings indicate that there are buildings with higher quantity of bars which they have higher probability of damage exceedance. Life-cycle cost analysis utilized for comparison and final decision making process.

Keywords: RC frame, fragility curve, performance-base design, life-cycle cost analyses, seismic design codes.

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6406 Investigating the Relation between Student Engagement and Attainment in a Flexible Learning Environment

Authors: Y. Bi, T. Anderson, M. Huang

Abstract:

The use of technology is increasingly adopted to support flexible learning in Higher Education institutions. The adoption of more sophisticated technologies offers a broad range of facilities for communication and resource sharing, thereby creating a flexible learning environment that facilitates and even encourages students not to physically attend classes. However this emerging trend seems to contradict class attendance requirements within universities, inevitably leading to a dilemma between amending traditional regulations and creating new policies for the higher education institutions. This study presents an investigation into student engagement in a technology enhanced/driven flexible environment along with its relationship to attainment. We propose an approach to modelling engagement from different perspectives in terms of indicators and then consider what impact these indicators have on student academic performance. We have carried out a case study on the relation between attendance and attainment in a flexible environment. Although our preliminary results show attendance is quantitatively correlated with successful student development and learning outcomes, our results also indicate there is a cohort that did not follow such a pattern. Nevertheless the preliminary results could provide an insight into pilot studies in the wider deployment of new technology to support flexible learning.

Keywords: Engagement, flexible leaning, attendance and attainment.

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6405 English as a Foreign Language Students’ Perceptions towards the British Culture: The Case of Batna 2 University, Algeria

Authors: Djelloul Nedjai

Abstract:

The issue of cultural awareness triggers many controversies, especially in a context where individuals do not share the same cultural backgrounds and characteristics. The Algerian context is no exception. It is extensively important to highlight how culture remains essential in many areas. In higher education, for instance, culture plays a pivotal role in shaping individuals’ perceptions and attitudes. Henceforth, the current paper attempts to look at the perceptions of the British culture held by students engaged in learning English as a Foreign Language (EFL) at the department of English at Banta 2 University, Algeria. It also inquiries into EFL students’ perceptions of British culture. To address the aforementioned research queries, a descriptive study has been carried out wherein a questionnaire of 15 items has been deployed to collect students’ attitudes and perceptions toward British culture. Results showcase that, indeed, EFL students of the department of English at Banta 2 University hold both positive and negative perceptions towards British culture at different levels. The explanation could relate to the student's lack of acquaintance with and awareness of British culture. Consequently, this paper is an attempt to address the issue of cultural awareness from the perspective of EFL students.

Keywords: British culture, cultural awareness, EFL students’ perceptions, higher education.

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6404 Terrorism: A Threat in Constant Evolution Still Misunderstood

Authors: Manuel J. Gazapo Lapayese

Abstract:

It is a well-established fact that terrorism is one of the foremost threats to present-day international security. The creation of tools or mechanisms for confronting it in an effective and efficient manner will only be possible by way of an objective assessment of the phenomenon. In order to achieve this, this paper has the following three main objectives: Firstly, setting out to find the reasons that have prevented the establishment of a universally accepted definition of terrorism, and consequently trying to outline the main features defining the face of the terrorist threat in order to discover the fundamental goals of what is now a serious blight on world society. Secondly, trying to explain the differences between a terrorist movement and a terrorist organisation, and the reasons for which a terrorist movement can be led to transform itself into an organisation. After analysing these motivations and the characteristics of a terrorist organisation, an example of the latter will be succinctly analysed to help the reader understand the ideas expressed. Lastly, discovering and exposing the factors that can lead to the appearance of terrorist tendencies, and discussing the most efficient and effective responses that can be given to this global security threat.

Keywords: Responses, resilience, security, terrorism.

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6403 Absorbed Dose Estimation of 68Ga-EDTMP in Human Organs

Authors: S. Zolghadri, H. Yousefnia, A. R. Jalilian

Abstract:

Bone metastases are observed in a wide range of cancers leading to intolerable pain. While early detection can help the physicians in the decision of the type of treatment, various radiopharmaceuticals using phosphonates like 68Ga-EDTMP have been developed. In this work, due to the importance of absorbed dose, human absorbed dose of this new agent was calculated for the first time based on biodistribution data in Wild-type rats. 68Ga was obtained from 68Ge/68Ga generator with radionuclidic purity and radiochemical purity of higher than 99%. The radiolabeled complex was prepared in the optimized conditions. Radiochemical purity of the radiolabeled complex was checked by instant thin layer chromatography (ITLC) method using Whatman No. 2 paper and saline. The results indicated the radiochemical purity of higher than 99%. The radiolabelled complex was injected into the Wild-type rats and its biodistribution was studied up to 120 min. As expected, major accumulation was observed in the bone. Absorbed dose of each human organ was calculated based on biodistribution in the rats using RADAR method. Bone surface and bone marrow with 0.112 and 0.053 mSv/MBq, respectively, received the highest absorbed dose. According to these results, the radiolabeled complex is a suitable and safe option for PET bone imaging.

Keywords: Absorbed dose, EDTMP, 68Ga, rats.

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6402 Health Risk Assessment of Heavy Metals in Clarias gariepinus (Burchell, 1822) from Fish Mongers within Akure Metropolis, Ondo State, Nigeria

Authors: O. O. Olawusi-Peters, K. I. Adejugbagbe

Abstract:

The concentration of heavy metal (Cd, Pb, Fe, Zn, Cu) in Clarias gariepinus collected from fish markets; Fanibi (Station I) and Fiwasaye (Station II) in Akure metropolis, Ondo state, Nigeria were investigated to ascertain the safety for the consumers. 60 samples were collected from the two markets in three batches (I, II, III) for a period of six months and analyzed for heavy metals in the gills and muscles of the fish. Also, the Health Risk Index (HRI) was used to determine the health risk of these metals to the consumer. The results showed that the investigated metal concentration was higher in station I than station II, except Pb having higher concentration in station II than station I. In both stations, the highest concentration of Fe was recorded in the gills (12.60 ± 1.51; 6.94 ± 1.38) and muscles (3.72 ± 0.09; 3.86 ± 0.33) of samples in batch I. Also, the HRI revealed that consumption of Clarias gariepinus from these study areas did not pose any health risk (HRI < 1). In addition, concentrations of the heavy metals were all below the permissible limits recommended by FAO/WHO.

Keywords: Health risk index, heavy metals, Clarias gariepinus, Akure metropolis, fish monger.

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6401 WhatsApp as Part of a Blended Learning Model to Help Programming Novices

Authors: Tlou J. Ramabu

Abstract:

Programming is one of the challenging subjects in the field of computing. In the higher education sphere, some programming novices’ performance, retention rate, and success rate are not improving. Most of the time, the problem is caused by the slow pace of learning, difficulty in grasping the syntax of the programming language and poor logical skills. More importantly, programming forms part of major subjects within the field of computing. As a result, specialized pedagogical methods and innovation are highly recommended. Little research has been done on the potential productivity of the WhatsApp platform as part of a blended learning model. In this article, the authors discuss the WhatsApp group as a part of blended learning model incorporated for a group of programming novices. We discuss possible administrative activities for productive utilisation of the WhatsApp group on the blended learning overview. The aim is to take advantage of the popularity of WhatsApp and the time students spend on it for their educational purpose. We believe that blended learning featuring a WhatsApp group may ease novices’ cognitive load and strengthen their foundational programming knowledge and skills. This is a work in progress as the proposed blended learning model with WhatsApp incorporated is yet to be implemented.

Keywords: Blended learning, higher education, WhatsApp, programming, novices, lecturers.

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6400 The Study of the Correlation of Proactive Coping and Retirement Planning: An Example of Senior Civil Servants in Taiwan

Authors: Ya-Hui Lee, Chien-Hung Hsieh, Ching-Yi Lu

Abstract:

Demographic aging is the major problem that Taiwanese society is facing, and retirement life adaptation is the most concerning issue. In recent years, studies have suggested that in order to have successful aging and retirement planning, a view for the future is necessary. In Taiwan, civil servants receive better pensions and retirement benefits than do other industries. Therefore, their retirement preparation is considerably more significant than other senior groups in Taiwan. The purpose of this study is to understand the correlation of proactive coping and retirement planning of senior civil servants in Taiwan. The method is conducted by questionnaire surveys, with 342 valid questionnaires collected. The results of this study are: 1. The background variables of the interviewees, including age, perceived economic statuses, and retirement statuses, are all significantly related to their proactive coping and retirement planning. 2. Regarding age, the interviewees with ages 55 and above have better proactive coping and retirement planning than those with ages 45 and below. 3. In the aspect of perceived economic statuses, the participants who feel “very good” economic statuses have better proactive coping ability and retirement readiness than those who feel “bad” and “very bad”. 4. Retirees have better proactive coping and retirement planning than those who are still working. 5. Monthly income is significant in retirement planning only. The participants’ retirement planning would be better if they have higher incomes. Furthermore, the participants’ retirement planning would be better if their revenue were €1453~€1937, than if their revenue were below €968. 6. There are positive correlations between proactive coping and retirement planning. 7. Proactive coping can predict retirement planning. The result of this study will be provided as references to the Taiwan government for educational retirement planning policies.

Keywords: Civil servants, proactive coping, retirement planning.

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6399 The Use of Microorganisms in the Bioleaching of Soils Polluted with Heavy Metals

Authors: I. M. Sur, A. M. Chirila-Babau, T. Gabor, V. Micle

Abstract:

This paper shows researches in order to extract Cr, Cu and Ni from the polluted soils. Research is based on preliminary studies regarding the usage of Thiobacillus ferrooxidans bacterium (9K medium) for bioleaching of soil polluted with heavy metal (Cu, Cr and Ni). The microorganisms (Thiobacillus ferooxidans) selected directly from polluted soil samples were used in this experimental work. Soil samples used in the experimental research were taken from an area polluted with heavy metals from Romania. The soil samples are subjected to the cleaning process using the 9K medium solution (20 mL and 40 mL, respectively), stirred 200 rpm for 20 hours at a controlled temperature (30 ˚C). During the experiment (0, 2, 4, 8 and 20 h), liquid samples have been extracted and analyzed using the Atomic Absorption Spectrophotometer AA-6800 (AAS) in order to determine the Cr, Cu and Ni concentration. Experiments led to the conclusion that these soils can be depolluted by bioleaching, being a biological treatment method involving the use of microorganisms to favor the extraction of Cr, Cu and Ni from polluted soils.

Keywords: Bioleaching, extraction, microorganisms, polluted soil, Thiobacillus ferooxidans.

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6398 Knowledge Acquisition and Client Organisations: Case Study of a Student as Producer

Authors: Barry Ardley, Abi Hunt, Nick Taylor

Abstract:

As a theoretical and practical framework this study uses the student as producer approach to learning in higher education, as adopted by the Lincoln International Business School, University of Lincoln, UK. Student as producer positions learners as skilled and capable agents, able to participate as partners with tutors in live research projects. To illuminate the nature of this approach to learning and to highlight its critical issues, the authors report on two guided student consultancy projects. These were set up with the assistance of two local organisations in the city of Lincoln UK. Using the student as producer model to deliver the projects enabled learners to acquire and develop a range of key skills and knowledge, not easily accessible in more traditional educational settings. This paper presents a systematic case study analysis of the eight organising principles of the student as producer model, as adopted by university tutors. The experience of tutors implementing student as producer suggests that the model can be widely applied to benefit not only the learning and teaching experiences of higher education students, and staff, but additionally, a university’s research programme and its community partners.

Keywords: Experiential learning, consultancy clients, student as producer.

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6397 The Impact of the Type of Diversification of Listed Construction Enterprises in China on Corporation Performance

Authors: Yi-Hsin Lin, Ying-Ying Li

Abstract:

The construction industry is the pillar industry in China, accounting for about 6% of the gross domestic product. Along with changes in the external environment of the construction industry in China, the construction firm faces fierce competition. The paper aims to investigate the relationship between diversified types of construction firm and its performance in China. Based on generalist and specialist strategy in organizational ecology, we think a generalist organization can be applied to an enterprise with diversified developments, while specialist groups are extended to professional enterprises .This study takes advantage of annual financial data of listed construction firm to empirically verify the relationship between diversification and corporation performance establishing a regression equation to econometric analysis. We find that: 1) Specialization can significantly improve the level of profitability of listed construction firms, and there is a significant positive relationship with corporate performance; 2) The level of operating performance of listed construction enterprises which engage in unrelated diversification is higher than those with related diversification; 3) The relationship between state-owned construction firms and corporate performance is negative. The more the year of foundation is, the higher performance will be; however, the more the year of being listed, the lower performance will be.

Keywords: Diversification, Specialization, Construction Firm, Performance.

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6396 Convection through Light Weight Timber Constructions with Mineral Wool

Authors: J. Schmidt, O. Kornadt

Abstract:

The major part of light weight timber constructions consists of insulation. Mineral wool is the most commonly used insulation due to its cost efficiency and easy handling. The fiber orientation and porosity of this insulation material enables flowthrough. The air flow resistance is low. If leakage occurs in the insulated bay section, the convective flow may cause energy losses and infiltration of the exterior wall with moisture and particles. In particular the infiltrated moisture may lead to thermal bridges and growth of health endangering mould and mildew. In order to prevent this problem, different numerical calculation models have been developed. All models developed so far have a potential for completion. The implementation of the flow-through properties of mineral wool insulation may help to improve the existing models. Assuming that the real pressure difference between interior and exterior surface is larger than the prescribed pressure difference in the standard test procedure for mineral wool ISO 9053 / EN 29053, measurements were performed using the measurement setup for research on convective moisture transfer “MSRCMT". These measurements show, that structural inhomogeneities of mineral wool effect the permeability only at higher pressure differences, as applied in MSRCMT. Additional microscopic investigations show, that the location of a leak within the construction has a crucial influence on the air flow-through and the infiltration rate. The results clearly indicate that the empirical values for the acoustic resistance of mineral wool should not be used for the calculation of convective transfer mechanisms.

Keywords: convection, convective transfer, infiltration, mineralwool, permeability, resistance, leakage

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6395 Environmental Study on Urban Disinfection Using an On-site Generation System

Authors: Víctor Martínez del Rey, Kourosh Nasr Esfahani, Amir Masoud Samani Majd

Abstract:

In this experimental study, the behaviors of Mixed Oxidant solution components (MOS) and sodium hypochlorite (HYPO) as the most commonly applied surface disinfectant were compared through the effectiveness of chlorine disinfection as a function of the contact time and residual chlorine. In this regard, the variation of pH, free available chlorine (FAC) concentration, and electric conductivity (EC) of disinfection solutions in different concentrations were monitored over 48 h contact time. In parallel, the plant stress activated by chlorine-based disinfectants was assessed by comparing MOS and HYPO. The elements of pH and EC in the plant-soil and their environmental impacts, spread by disinfection solutions were analyzed through several concentrations of FAC including 500 mg/L, 1000 mg/L, and 5000 mg/L in irrigated water. All the experiments were carried out at the service station of Sant Cugat, Spain. The outcomes indicated lower pH and higher durability of MOS than HYPO at the same concentration of FAC which resulted in promising stability of FAC within MOS. Furthermore, the pH and EC value of plant-soil irrigated by NaOCl solution were higher than that of MOS solution at the same FAC concentration. On-site generation of MOS as a safe chlorination option might be considered an imaginary future of smart cities.

Keywords: Disinfection, free available chlorine, on-site generation, sodium hypochlorite.

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6394 Study of Barriers to Women's Entrepreneurship Development among Iranian Women (Case Entrepreneur Women)

Authors: F. Niazkar, N. Arab-Moghaddam

Abstract:

In this research, effort was made to identify and evaluate barriers to the development of entrepreneurship among Iranian entrepreneur women who were graduated from universities. In this study, perspectives of thirty-seven available entrepreneur women were examined. In order to prepare questionnaires and receive knowledge about barriers among these women, seven cases of entrepreneur women took part in in-depth interviews. Then, to evaluate the importance of barriers, the researchers made a questionnaire with closed questions in which the barriers were classified into the following categories: personal-familial barriers; socio-cultural barriers; economic-financial-commercial barriers; and structural barriers. Entrepreneur women were requested to rate the importance of each item. The results indicated that there were different obstacles among entrepreneur women. The order of the important barriers was as fallow: economic-financial-commercial, structural, socio-cultural, and personal-familial.

Keywords: Barriers to Entrepreneurship, Entrepreneur Women

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6393 Chitosan/Casein Microparticles: Preparation, Characterization and Drug Release Studies

Authors: Selvakumar Dhanasingh, Shunmuga Kumar Nallaperumal

Abstract:

Microparticles carrier systems made from naturally occurring polymers based on chitosan/casein system appears to be a promising carrier for the sustained release of orally and parenteral administered drugs. In the current study we followed a microencapsulation technique based aqueous coacervation method to prepare chitosan/casein microparticles of compositions 1:1, 1:2 and 1:5 incorporated with chloramphenicol. Glutaraldehyde was used as a chemical cross-linking agent. The microparticles were prepared by aerosol method and studied by optical microscopy, infrared spectroscopy, thermo gravimetric analysis, swelling studies and drug release studies at various pH. The percentage swelling of the polymers are found to be in the order pH 4 > pH 10 > pH 7 and the increase in casein composition decrease the swelling percentage. The drug release studies also follow the above order.

Keywords: Chitosan/casein micro particles, chloramphenicol, drug release, microencapsulation.

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6392 The Effect of Peer Support to Interpersonal Problem Solving Tendencies and Skills in Nursing Students

Authors: B. Özlük, A. Karaaslan

Abstract:

This study has been conducted as a supplementary and relationship seeking study with the purpose of measuring the tendency and success of support among peers amid nursing students studying at university in solving interpersonal problems. The population of the study (N:279) is comprised of nursing students who are studying at one state and one private university in the province of Konya, while its sample is comprised of 231 nursing students who agreed to take part in the study voluntarily. As a result of this study, it has been determined that the peer support and interpersonal problem solving characteristics among students were at medium levels and that the interpersonal problem solving skills of students studying in the third year were higher than those of first and second year students. While the interpersonal problem solving characteristics of students who are aged 20 and over were found to be higher, no difference could be determined in terms of the interpersonal problem solving skills and tendencies among students, based on their gender and where they reside. A positive – to a medium degree – and significant relationship was determined between peer support and interpersonal problem solving skills, and it is possible to say that as peer support increases, so do the skills and tendencies to solve problems.

Keywords: Interpersonal problem, nursing students, peer support, problem solving.

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6391 Developing Creative and Critically Reflective Digital Learning Communities

Authors: W. S. Barber, S. L. King

Abstract:

This paper is a qualitative case study analysis of the development of a fully online learning community of graduate students through arts-based community building activities. With increasing numbers and types of online learning spaces, it is incumbent upon educators to continue to push the edge of what best practices look like in digital learning environments. In digital learning spaces, instructors can no longer be seen as purveyors of content knowledge to be examined at the end of a set course by a final test or exam. The rapid and fluid dissemination of information via Web 3.0 demands that we reshape our approach to teaching and learning, from one that is content-focused to one that is process-driven. Rather than having instructors as formal leaders, today’s digital learning environments require us to share expertise, as it is the collective experiences and knowledge of all students together with the instructors that help to create a very different kind of learning community. This paper focuses on innovations pursued in a 36 hour 12 week graduate course in higher education entitled “Critical and Reflective Practice”. The authors chronicle their journey to developing a fully online learning community (FOLC) by emphasizing the elements of social, cognitive, emotional and digital spaces that form a moving interplay through the community. In this way, students embrace anywhere anytime learning and often take the learning, as well as the relationships they build and skills they acquire, beyond the digital class into real world situations. We argue that in order to increase student online engagement, pedagogical approaches need to stem from two primary elements, both creativity and critical reflection, that are essential pillars upon which instructors can co-design learning environments with students. The theoretical framework for the paper is based on the interaction and interdependence of Creativity, Intuition, Critical Reflection, Social Constructivism and FOLCs. By leveraging students’ embedded familiarity with a wide variety of technologies, this case study of a graduate level course on critical reflection in education, examines how relationships, quality of work produced, and student engagement can improve by using creative and imaginative pedagogical strategies. The authors examine their professional pedagogical strategies through the lens that the teacher acts as facilitator, guide and co-designer. In a world where students can easily search for and organize information as self-directed processes, creativity and connection can at times be lost in the digitized course environment. The paper concludes by posing further questions as to how institutions of higher education may be challenged to restructure their credit granting courses into more flexible modules, and how students need to be considered an important part of assessment and evaluation strategies. By introducing creativity and critical reflection as central features of the digital learning spaces, notions of best practices in digital teaching and learning emerge.

Keywords: Online, pedagogy, learning, communities.

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6390 Evaluation of Dynamic Behavior a Machine Tool Spindle System through Modal and Unbalance Response Analysis

Authors: Khairul Jauhari, Achmad Widodo, Ismoyo Haryanto

Abstract:

The spindle system is one of the most important components of machine tool. The dynamic properties of the spindle affect the machining productivity and quality of the work pieces. Thus, it is important and necessary to determine its dynamic characteristics of spindles in the design and development in order to avoid forced resonance. The finite element method (FEM) has been adopted in order to obtain the dynamic behavior of spindle system. For this reason, obtaining the Campbell diagrams and determining the critical speeds are very useful to evaluate the spindle system dynamics. The unbalance response of the system to the center of mass unbalance at the cutting tool is also calculated to investigate the dynamic behavior. In this paper, we used an ANSYS Parametric Design Language (APDL) program which based on finite element method has been implemented to make the full dynamic analysis and evaluation of the results. Results show that the calculated critical speeds are far from the operating speed range of the spindle, thus, the spindle would not experience resonance, and the maximum unbalance response at operating speed is still with acceptable limit. ANSYS Parametric Design Language (APDL) can be used by spindle designer as tools in order to increase the product quality, reducing cost, and time consuming in the design and development stages.

Keywords: ANSYS parametric design language (APDL), Campbell diagram, Critical speeds, Unbalance response, The Spindle system.

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6389 Development of an Autonomous Friction Gripper for Industrial Robots

Authors: Majid Tolouei-Rad, Peter Kalivitis

Abstract:

Industrial robots become useless without end-effectors that for many instances are in the form of friction grippers. Commonly friction grippers apply frictional forces to different objects on the basis of programmers- experiences. This puts a limitation on the effectiveness of gripping force that may result in damaging the object. This paper describes various stages of design and development of a low cost sensor-based robotic gripper that would facilitate the task of applying right gripping forces to different objects. The gripper is also equipped with range sensors in order to avoid collisions of the gripper with objects. It is a fully functional automated pick and place gripper which can be used in many industrial applications. Yet it can also be altered or further developed in order to suit a larger number of industrial activities. The current design of gripper could lead to designing completely automated robot grippers able to improve the efficiency and productivity of industrial robots.

Keywords: Control system, end-effector, robot, sensor

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