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Study on Satisfaction According to Result of Participants in DIY Woodworking Program

  • Chun, Tong-Whan;Kim, Kwang-Roul
    • Journal of the Korea Furniture Society
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    • v.19 no.6
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    • pp.487-497
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    • 2008
  • This study was the research of the satisfaction of participation in short DIY Woodworking program organized by university as productive leisure activity. It is the study of what satisfactions-factors of the participants are and how the satisfaction is continued with activities of the participants later on, and finally how the satisfaction influences the choice of leisure activity further. Questionnaire is consist of total 41 survey standards like the article for facility, education, service and cost & the demographic contents of the participants. It was executed by the participants in program at sight from Aug. $1^{st}$ and $2^{nd}$ 2008, and the valid samples 156 copies were definitely analyzed. The result of analysis shows first that the majority of the participants in the short leisure program are the beginner who took part in such program for the first time. What them interests are the convenient facility & use of tools. Second, the reasonable fees in terms of material cost & preparation of personal tools influenced positively on satisfaction of participation. Third, the dissatisfaction of participants regarding educational method and service could be solved by that the trainer who makes practical lesson had been informed of the course in advance.

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Posture Change Affects Indices of Pupil Size - Korean Males in Their Twenties

  • Lee, Jeung-Chan;Kim, Ji-Eun;Park, Kyung-Mo
    • Journal of Biomedical Engineering Research
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    • v.28 no.1
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    • pp.1-7
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    • 2007
  • To determine the effect of posture change on autonomic activity and to investigate valid parameters to reflex the autonomic activity from time-series pupil size data, a posture-related experiment was performed with 15 subjects, which involved measuring their electrocardiograms and pupil sizes. The experimental procedure consisted of three-sequence postures-supine, sitting and upright-for 5 minutes each, with rest sessions between postures. The subjects were notified of the entire experimental procedure. The parameters of the subjects' heart rate variability showed significant differences between the postures (heart rate: 63-70-80 beat, normalized low frequency power: 28-50-75, normalized high frequency power: 72-49-25 and ratio: 0.5-1.2-4.4 in supine-sitting-upright position respectively) as did the parameters of their mean pupil sizes (41300-53900-53700 pixels respectively) and the major frequencies (the third trend: 0.23-0.2-0.18 Hz respectively) of their pupil size variability according to changes in their autonomic activities induced by posture change. The experiment thus proved that posture change affects autonomic activity and that such activity can be estimated by the parameters of pupil size as similar as heart rate variability.

A Case study of Elementary Mathematics Class in a Constructive View (초등수학에서 구성주의적 관점에서의 수업 사례연구)

  • 최창우
    • Journal of Educational Research in Mathematics
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    • v.10 no.2
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    • pp.229-246
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    • 2000
  • The purpose of this paper is to compare and analyze the two different teaching methods of elementary mathematics in the traditional method and in the constructive view. To do so, the actual class in the constructive view has been made for about four months using a class of 45 students in the second grade of an elementary school. After the class was finished, we collected diverse data from the class, such as the responses from the children(self-evaluation, mathematics diary, observation by the investigator, daily report), class evaluation report by other teacher and so on. The results of this research are as follows: First, the traditional class reaches at the goal of learning in a unit time because the class is guided by the teacher but the class in the constructive view is a little flexible because it is contextual. Second, in the constructive process of mathematical knowledge we knew that small group activities or discussion without intervention of teacher was often ended in exhaustive argument without arriving at valid social consensus. Third, the attitude in mathematics was changed from the passive one to the self-regulated ones. Fourth, the class in the constructive view could extend not only the ability of mathematical communication but also the ability of self-directed learning of children. Fifth, it was a considerable change the role of teacher, that is, guide of instruction instead of unique specialist in the classroom. Sixth, finally, the evaluation was made after finishing a unit class in the traditional instruction but it was integrated in a class in a constructive view.

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State Transformations for Regenerative Sampling in Simulation Experiments

  • Kim, Yun-Bae
    • IE interfaces
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    • v.11 no.3
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    • pp.89-101
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    • 1998
  • The randomness of the input variables in simulation experiments produce output responses which are also realizations of random variables. The random responses make necessary the use of statistical inferences to adequately describe the stochastic nature of the output. The analysis of the simulation output of non-terminating simulations is frequently complicated by the autocorrelation of the output data and the effect of the initial conditions that produces biased estimates. The regenerative method has been developed to deal with some of the problems created by the random nature of the simulation experiments. It provides a simple solution to some tactical problems and can produce valid statistical results. However, not all processes can he modeled using the regenerative method. Other processes modeled as regenerative may not return to a given demarcating state frequently enough to allow for adequate statistical analysis. This paper shows how the state transformation concept was successfully used in a queueing model and a job shop model. Although the first example can be analyzed using the regenerative method. it has the problem of too few recurrences under certain conditions. The second model has the problem of no recurrences. In both cases, the state transformation increase the frequency of the demarcating state. It was shown that time state transformations are regenerative and produce more cycles than the best typical discrete demarcating state in a given run length.

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Moderate Effect of JIT and Workforce Management on Infra and Process Factor in Quality Management Practices (품질경영 실행방식 요인과 성과 간 관계에 대한 JIT와 인력관리의 조절 효과)

  • Park, Jeong-Soo;Chang, Deok-Shin;Kim, Soo-Wook
    • Korean Management Science Review
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    • v.27 no.3
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    • pp.99-115
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    • 2010
  • We classified quality management practices of manufacturing companies into 'Infra' factor and 'Process' factor which were introduced based on existing literatures and previous studies related to quality management. It was our first objective to confirm its conformance in Korean manufacturing industry, and to examine the two factors effect positively on production performance. Moreover, we tried to examine whether JIT and workforce management have an moderate effect on 'Infra and Process factors-performance' relationship, using moderate regression. As the result of empirical study on nationwide manufacturing companies, we had the results that the classification between Infra factor and Process factor in quality management practices was valid in Korean manufacturing companies, and that the two factors gave performances positive effect. Moreover, our secondary analysis showed that JIT had an positive moderate effect on the Infra factor while workforce management on the Process factor. With these results, we have an interpretation that manufacturing companies which aim to enhance short term performances have to concentrate their effort and investment on Process factor and, on the other hand, ones which aims to improve long term performances on Infra factor.

Optimal stiffness distribution in preliminary design of tubed-system tall buildings

  • Alavi, Arsalan;Rahgozar, Reza
    • Structural Engineering and Mechanics
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    • v.65 no.6
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    • pp.731-739
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    • 2018
  • This paper presents an optimal pattern for distributing stiffness along a framed tube structure through an analytic equation, which may be used during the preliminary design stage. Most studies in this field are computationally intensive and time consuming, while a hand-calculation method, as presented here, is a more suitable tool for sensitivity analyses and parametric studies. Approach in development of the analytic model is to minimize the mean compliance (external work) for a given volume of material. A variational statement of the problem is made, and a specified deformation-profile is obtained as the necessary condition for a minimum; enforcing this condition, stiffness is then computed. Due to some near-zero values for stiffness, the problem is modified by considering a lower bound constraint. To deal with this constraint, the design domain is assumed to be divided into two zones of constant stiffness and constant curvature; and the problem is restated in terms of these concepts. It will be shown that this methodology allows for easy computation of stiffness through an analytic and dimensionless equation, valid in any system of units. To show practicality of the proposed method, a tubed-system structure with uniform stiffness distribution is redesigned using the proposed model. Comparative analyses of the results reveal that in addition to simplicity of the proposed method, it provides a rather high degree of accuracy for real-world problems.

ENERGY UTILIZATION MODELS OF CATTLE GRAZING IN OIL PALM PLANTATIONS II. VALIDATION OF MODELS

  • Dahlan, I.;Mahyuddin, M.D.;Yamada, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.1
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    • pp.67-73
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    • 1995
  • This study showed that models of energy utilization(EU) developed for grazing cattle in oil palm plantations is valid as the simulated results shows an agreement with actual data of calves and cows body weight changes collected from Brahman x Kedah-Kelantan herd on Pengeli Timor Plantation. Simulation runs on EU models demonstrated that the growth pattern of male and female calves and the weight changes of cows are similar and showed slight variation from the actual data but with no significant difference (p > 0.05). Parameter values such as metabolizability (q), dry matter digestibility(DMD) of herbage and voluntary intake of grazing cattle (VIG) and faecal output/body weight ratio (F) of the animals which were collected from the field are essential in bearing the pattern of body weight changes of the calves and cows in relation to increase in time, physiological status and quality of herbage grazed by these animals in the production system. The EU models is suitable for determining the metabolizable energy requirements and to predict the production of grazing cattle according to quality of the feed on offer.

Motives for Participating in Sharing Economy: Intentions to Use Car Sharing Services

  • Joo, Jae-Hun
    • Journal of Distribution Science
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    • v.15 no.2
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    • pp.21-26
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    • 2017
  • Purpose - Sharing economy is a promising research topic as a complementary approach for solving difficult issues resulting from market economy. Motive factors for consumer participation in sharing economy are necessary to facilitate the growth of sharing economy. This study analyzes motives for participating in sharing economy using samples from a car sharing service in South Korea. Research design, data, and methodology - Four hypotheses drawn from a new research model integrating the relationships between economic and social value, social value, and the intention to use sharing economy services were proposed. 292 valid samples were collected from Socar users in South Korea. Multiple regression analysis was employed to test the hypotheses. Results - An empirical study identified the importance of convenience and time savings as determinants of intention to use continuously a car sharing service. Cost savings and social value did not significantly influence the intention to use car sharing service. Conclusions - The present study implies that managers working in sharing economy don't have to miss a role of convenience. Although a new finding implies that convenience is an important factor influencing car sharing service, the present study has a limitation of generality that samples are mostly collected from the age range of 20 to 30 years.

Development of Cost-effective Mosquito Repellent and Distribution Method by Extracting Patchouli Oil

  • KWON, Woo-Taeg;KWON, Lee-Seung;YOO, Ho-Gil;LEE, Woo-Sik
    • The Journal of Industrial Distribution & Business
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    • v.10 no.12
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    • pp.15-23
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    • 2019
  • Purpose : We will develop the distribution method of wide oil extract technology to develop repellent using this technology and study mosquito repellent persistence. Research design, data and methodology : A positive control group containing purified water, ethanol and picaridin was prepared, and the experimental control group was prepared in the same proportion as the positive control group, and 0.6% of broad oil was added. The results were summarized using the calculation method according to the avoidance effect and statistically tested by t-test using the excel statistics program. Results : Experiments on skin surface area and voice control of participants showed that men had 8.9% wider skin surface area than women, and voice control tests showed that women were bitten by mosquitoes five times more than men. Both the positive and the experimental control groups had a valid duration of up to three hours, but from the time of five hours, the positive control group had 77% and the experimental control had 90%, indicating a difference of 14.4% over the positive control group. Conclusions : The mosquito repellents developed in this study on the basis of safety and continuity are cost-effective in terms of mosquito repellent, and in addition fragrance, odor removal, perfume, ink, skin care and massage effect.

Traffic Light Recognition Based on the Glow Effect at Night Image (야간 영상에서의 빛 번짐 현상을 이용한 교통신호등 인식)

  • Kim, Min-Ki
    • Journal of Korea Multimedia Society
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    • v.20 no.12
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    • pp.1901-1912
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    • 2017
  • Traffic lights at night are usually framed in the image as bright regions bigger than the real size due to glow effect. Moreover, the colors of lighting region saturate to white. So it is difficult to distinguish between different traffic lights at night. Many related studies have tried to decrease the glow effect in the process of capturing images. Some studies drastically decreased the shutter time of the camera to reduce the adverse effect by the glow. However, this makes the video too dark. This study proposes a new idea which utilizes the glow effect. It examines the outer radial region of traffic light. It presents an algorithm to discriminate the color of traffic light by the analysis of the outer radial region. The advantage of the proposed method is that it can recognize traffic lights in the image captured by an ordinary black box camera. Experimental results using seven short videos show the performance of traffic light recognition reporting the precision of 96.4% and the recall of 98.2%. These results show that the proposed method is valid and effective.