• Title/Summary/Keyword: Behaviour Quality

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Enhanced Crystallization Behaviour and Microwave Dielectric Properties of 0.9CaMgSi2O6-0.1MgSiO3 Glass-Ceramics Doped with TiO2

  • Jo, Hyun Jin;Sun, Gui Nam;Kim, Eung Soo
    • Journal of the Korean Ceramic Society
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    • v.53 no.2
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    • pp.139-144
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    • 2016
  • The dependence of the microwave dielectric properties of the glass-ceramic composite $0.9CaMgSi_2O_6-0.1MgSiO_3$ on the crystallization behaviour was investigated as functions of the $TiO_2$ content and heat-treatment temperature. The crystallization behaviour of the specimens was evaluated via a combination of the Rietveld and reference-intensity ratio methods. For specimens with a $TiO_2$ content of up to 1 wt.%, a monoclinic diopside phase was formed, whereas a secondary $TiO_2$ phase was formed with further increases in the $TiO_2$ content. The quality factor (Qf) of the specimens was strongly dependent on the degree of crystallization. The highest Qf value was obtained with a $TiO_2$ content of 0.5 wt.%, which was improved by increasing the heat-treatment temperature. The dielectric constant (K) was affected by the size of the crystallites and the $TiO_2$ content. The temperature coefficient of the resonant frequency (TCF) was nearly constant for all of the specimens, regardless of the $TiO_2$ content or heattreatment temperature.

Modelling the rheological behaviour of fresh concrete: An elasto-viscoplastic finite element approach

  • Chidiac, S.E.;Habibbeigi, F.
    • Computers and Concrete
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    • v.2 no.2
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    • pp.97-110
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    • 2005
  • Rheological behaviour of fresh concrete is an important factor in controlling concrete quality. It is recognized that the measurement of the slump is not a sufficient test method to adequately characterize the rheology of fresh concrete. To further understand the slump measurement and its relationship to the rheological properties, an elasto-viscoplastic, 2-D axisymmetric finite element (FE) model is developed. The FE model employs the Bingham material model to simulate the flow of a slump test. An experimental program is carried out using the Slump Rate Machine (SLRM_II) to evaluate the finite element simulation results. The simulated slump-versus-time curves are found to be in good agreement with the measured data. A sensitivity study is performed to evaluate the effects of yield stress, plastic viscosity and cone withdrawal rate on the measured flow curve using the FE model. The results demonstrate that the computed yield stress compares well with reported experimental data. The flow behaviour is shown to be influenced by the yield stress, plastic viscosity and the cone withdrawal rate. Further, it is found that the value of the apparent plastic viscosity is different from the true viscosity, with the difference depending on the cone withdrawal rate. It is also confirmed that the value of the final slump is most influenced by the yield stress.

The Perception of Women Consumers on Buying Behaviour with Reference to Vellore District of Tamil Nadu, India

  • Sundaram, N.;Sriram, M.
    • Asia-Pacific Journal of Business
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    • v.4 no.2
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    • pp.31-40
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    • 2013
  • This paper portrays the perception of buying behaviour, factors of product preferences and product switch-over among women consumers in Vellore district of Tamil Nadu. To conduct this study, 300 respondents from 20 village blocks of Vellore district were selected using stratified random sampling as the technique and descriptive sampling as the design. The study came out with interesting results and conclusions. It was found that more than half of the respondents were purchasing the product without a bill. It was also found that the respondents who repaired their product in the authorized service centre during warranty period did not continue the same after the warranty period and preferred nearby repair shops. It was further found that more than half of the respondents were checking expiry date and quality standards while purchasing a product. The study's scope was limited to women consumers at Vellore district. It could be used for further research in other aspects such as gender comparison in Vellore district and comparison with other districts of Tamil Nadu and other states of India. It was suggested that there is still a necessity to upgrade the standard of the people in many aspects like education, occupation and level of income, which shall help them to compete with the neighboring cities on living standards.

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A Study on Efficient Design Technique of RPUM Steel Pipes (RPUM 강관의 효율적인 설계기법에 관한 연구)

  • Kim, Jung-Su;Park, Tae-Soon
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.1354-1363
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    • 2006
  • Until now, NATM(New Austrian Tunneling Method) has been increasingly developed based on concept of making use of ground as support. Also, NATM in its essence is a method of risk based on monitoring behaviour of tunnel. This Monitoring is irreplaceable for the quality construction of tunnel, and safety of tunnel itself. Pre-reinforcement ahead of a tunnel face using long steel pipes in NATM, known as the RPUM(Reinforced Protective Umbrella Method), is the auxiliary method to sustain the stability of a tunnel face and reduce the ground settlements. Since design of RPUM has been dependent on the empirical design, it is necessary to develop the improved design methods. In this study, to understand behaviour of steel pipes, it is monitored displacement of tunnel crown, axial force of rock bolt, displacement and axial stress of steel pipes. Also, in order to clarify the mechanical behaviour and RPUM effects, 3-Dimensional numerical analysis is performed that various cases of different parameter combinations including original length and repeated length of steel pipes, installation width and angle, repeated length of steel. In the results of comparison monitoring with analysis, it is suggested more economical and efficient design technique than empirical design methods.

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Information Seeking Behaviour of Distance Learners: What has Changed During the Covid-19?

  • Alturki, Ryan
    • International Journal of Computer Science & Network Security
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    • v.22 no.5
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    • pp.182-192
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    • 2022
  • All the aspects of human life have been affected by the novel coronavirus (Covid-19). It has rapidly spread in most countries including the Kingdom of Saudi Arabia. As a result, early precautionary actions aiming to minimise the virus effect are taken by the Saudi government. One of these actions is the sudden shift to online classes and suspending the attendees to all educational institutes. Such immediate change can have a significant effect on the educational process, especially for students. One can argue that students' information-seeking behaviour within the current situation can affect their learning quality and outcomes. Therefore, this paper examines the Saudi students' information-seeking behaviour by taking a sample of students from Umm Al-Qura University. A descriptive analysis is conducted with 193 students and two approaches are used to collect data, questionnaire and semi-structured interview. The results showed that the majority of students face difficulties when searching and retrieving e-resources from the university library website. The problems range from mainly poor User Experience (UX), network connection, multiple errors and lack of subscription with academic publishers.

Factors Related to Health Behavior and Health-Related Quality of Life Among Obese High School Youths (청소년의 비만도에 따른 건강행위 실천과 건강관련 삶의 질과의 관련성)

  • Kim, Sun-Hye;Kim, Myung
    • The Journal of Korean Society for School & Community Health Education
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    • v.9 no.1
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    • pp.47-61
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    • 2008
  • Objectives: This study examined to explain the practical health behaviour and health-related quality of life, and their influencing factors in high school students. Methods: Total of 718 high school students from 1 school in Seoul were assessed with a self-administered questionnaire regarding general characteristics, health related characteristics, obesity index(Height and weight calculated by using the relative weight law: obesity group>20%, overweight group $10{\sim}20%$, normal weight group $-10{\sim}10%$, under weight group <-10%), health behaviour in school-aged children(eating, exercise and weight control) and health-related quality of life(PedsQLTM4.0 Generic Core Scale: physical health, emotional functioning, social functioning, school functioning). Results: Major results were as follows. 1. The rate of obesity by obesity index was 5.3% of high school students. Obesity incidence in adolescents was mainly associated with gender and parents whether obesity. 2. Perceived health status was lower in obese adolescents than in normal adolescents. 3. The rate of miss a breakfast was 37.9%, and obesity group than normal weight group were fruits, vegetables and milk intake at least, a lot of fastfood intake. During the past week, followed by intense physical activity, and overweight consumed a lot of time for TV and the Internet. Overall, under weight group and normal weight group belong to the students evaluated fatter than themselves. Weight control for weight loss, gain and maintain was grater in obesity group than in normal weight group. Weight loss showed highest scores in overweight group which appeared significant difference. 4. Obese adolescents compared with other groups, reported lower total QOL score and all QOL in domain, and especially social functioning showed significant differences. 5. Factors influencing the adolescents's QOL were found to be gender, perceived health status and exercise. Conclusions: High school girls were aware of their bad health status and likely to improve the QOL by practicing health behaviour. But obese adolescents were likely to degrade the quality of life by reducing the practice of health behaviors. So further school-based education about proper practical health behaviors and obesity prevention is necessary.

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The Implementation of a Quality System in the Care Sector for Elderly and Handicapped People: A Swedish Case Study

  • Anbacken Owe;Dahlgaard-Park Su Mi
    • International Journal of Quality Innovation
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    • v.6 no.3
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    • pp.1-18
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    • 2005
  • This paper presents the empirical research results conducted in a Swedish care organization for elderly and handicapped. The objective of the research was to empirically assess the implementation and practices of a quality system (ISO 9000) from an organizational change and development perspective. The empirical data were collected through multiple methods; interviews were carried out with key-persons and leadership in the organisation and surveys were conducted to all employees. Interactive methods have been applied to various groups in the organisations e.g., directors, supervisors, and the leadership of the quality project and the local politicians. The empirical findings indicate, among others, that the implementation processes were received and perceived differently in the different parts of the care organisation due to different leadership strategies and employee involvement policies. Other critical factors such as acceptance, resistance, motivation, commitment, the role of leadership, learning possibility, etc. have also been investigated, analysed and discussed. Finally some recommendations on how to approach organisational change as well as strategies for implementing a quality system in the care sector are presented.

Analysis on Consumption Efficiency of IT and Electronic Products (정보통신 및 전력 제품에 대한 소비자 효율성 연구)

  • Son, Sung-Yong;Lee, Misuk;Kim, Chang Seob
    • Environmental and Resource Economics Review
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    • v.18 no.2
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    • pp.191-215
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    • 2009
  • In the real world, there exist various products in terms of price and quality, and it can be expected that a product with lower price and higher quality than others is better. Hence efficiency of consumption behaviour can be measured by the level of goodness in terms of price and quality attributes of that product. The purpose of this research is to define consumption efficiency in terms of price and quality, and to measure consumption efficiency of IT and electronic products in South Korea. From the results, many consumers have purchased inefficient products m air-conditioner, TV, digital camera, MP3 player, computer markets. On the other hand, consumers have purchase efficient products in refrigerator and washing machine markets relatively. In addition, we analyze the relationship of consumption efficiency, information channel, and electric power consumption. This research may provide meaningful information for consumer's behaviour by measuring consumption efficiency quantitatively.

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Quality and Measure Controls for Plastic Board Drains Method (PBD공법의 품질 및 계측관리)

  • 박영목
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.10a
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    • pp.133-145
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    • 2001
  • This paper presents quality and measure controls of Plastic Board Drains(PBD) for improvement of soft ground. Laboratory and field tests has been carried out to evaluate the quality of PBD focussing on : discharge capacity of flow area; permeability of filter sleeve; migration of fine particles; deformed shape of PBD; consolidation of clay in the close vicinity of PBD; tensile strength of PBD; long-term consolidation behavior of clay-PBD. Test results show that the quality of PBD is sufficient to perform the improvement of soft silty and clayey ground. But, geotechnical engineer must make efforts minimizings of PBD damage and ground disturbance, continuity of drainage system during construction. Adequate monitoring system should apply at ground focussing on number, location, and accuracy of geotechnical instrumentation, measurement and evaluation of data for ground behaviour.

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Dynamic Behaviour Analysis of a Hydraulic Control System for Vehicle Active Suspension (차량 능동현가장치용 유압 제어시스템의 동적거동 해석)

  • Jung, Y.G.;Lee, I.Y.
    • Journal of Power System Engineering
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    • v.4 no.1
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    • pp.51-59
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    • 2000
  • Active suspension systems have been using for improving ride quality and stability for vehicles. An active suspension system is composed of a hydraulic pump, pressure control valves, hydraulic dampers, vehicle body, tires and other components. In this study, the mathematical model for the active suspension system based on the quarter car concept is derived, and a program for analysing the dynamic behaviour of the suspension system is developed. The computed results by the developed program are compared with the experimental results for confirming the reliability and usefulness of the developed program.

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