• Title/Summary/Keyword: frequency problem

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A Study on the melting Characteristics of Fuse Element by Repeating Overcurrent (반복과전류에 의한 퓨즈 엘리먼트의 용단특성에 관한 연구)

  • Kim, Youn-Hyun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.2
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    • pp.120-126
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    • 2010
  • This paper propose analysis and examination of the melting characteristic of fuse elements by repeating overcurrent as a depletion factor of high pressure current limiting fuse through test following existence and nonexistence of extinction material and various configuration of elements. To examine deterioration progress rate by repeating overcurrent we analyzed heat for various element notching configuration, designed plate type, ring type element and estimated the relationship with life span by analyzing breaking characteristic through repeating overcurrent test with adjusting load factor at Silicon Dioxide(SiO2) filled state or in air. A Crack by repeat stress, decrease of section and transformation by friction with extinction material by repeating overcurrent causes a problem which shortens life span based on fuse repeating frequency. Since the contents of this paper might be useful to research the correlation between friction of materials and repeating life span based on load factor of repeating current, the quality of product would be improved through solution of the problem.

Problem Analysis and Study of Solution Device in Relation with Middle School Mathematics Performance Assessment (중학교 수학과 수행평가의 문제점 분석 및 그 해결 방안 연구)

  • 박재용
    • Journal of the Korean School Mathematics Society
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    • v.3 no.1
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    • pp.149-163
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    • 2000
  • The Ministry of Education have had us practice the performance test as a substitute proposal, however, all the more for the idealistic purport, our education front does not have such a sufficient condition as to practice the performance test for many classes and miscellaneous duties and over-populated class, and that practice has been enforced so abruptly without any drastic preparation and has caused much confusion from the beginning of that enforcement. Thus, these problematic concerns are remained as the tasks of the teachers to be solved by themselves in the front of education, and herein I came to do this research. The followings are the conclusions that I got as the results of the research (1) Performance test style should be applied in consideration of the students' achievement level and the gap of the teachers' recognition; descriptive test, portfolio assignment and formative test styles were proper for the students lacking basic study ability. (2) Descriptive test should have its beginning with the question items to which students can write the problem solving procedure logically rather than those to evaluate the creation ability and thinking ability: and putting down specifically the assessment standard could prevent students' confusion and scheme the impartiality of the assessment. (3) Portfolio assignment evaluation should be given with as interesting and suitable amounts as possible so that the students can do by themselves. (4) Utilizing the performance test table enabled easy management of documentary evidence. And it is needless to say that the success of the performance test should have preceding conditions like the teachers' understanding and their positive participation. Therefore, I'd like to give suggestions herein like the followings; (1) The performance test should not always be made into grades, and there is a need to develop the test gradually in the condition that the education surroundings permit by checking time, frequency, ratio and contents of the test while practicing the multiple choice writing test. (2) As long as the performance test has the aims of improving the studying and learning activities, any performance test only for the sake of making numerals with the thought that assessment is the disposal of the grades should be avoided, and the change of the lecturing styles and development of various assessing types and studying materials should be endeavored to confirm with the aims.

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Tag Mis-recognition Detection using RFID Tag Sensitivity in Logistics System (물류 시스템에서 RFID 태그 수신감도를 이용한 태그 오인식 검출)

  • Kim, Youngmin;Kang, Euisun
    • The Journal of the Korea Contents Association
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    • v.15 no.8
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    • pp.9-17
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    • 2015
  • One of RFID features is that each RFID tag has a unique identifying code. Logistic System utilizes RFID tag as location tracing, understanding stock or etc. On the other hand, there is a problem of overall lower recognition rate by getting the information of non-mobility tags with no need for reading. To solve this problem, we trace and analyze variation of moving and moveless RFID tag sensitivity by the hour. In analyzed data, we verify that tag sensitivity of mobile RFID is gradually increase while non-mobility tag has same intensity value. In order to detect mobile tag, we generate a function using Matlab with analyzed data and separate moving tags from non-mobility tags by software. As a result, we can confirm that non-mobility tags are detected by software and recognition rate of RFID tag is improved by separating moveless tag.

Sex Role Identity and Health Behavior among University Student (대학생의 성역할정체감과 건강행위)

  • Park, Eun-Ok;Park, Young-Sook
    • Women's Health Nursing
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    • v.5 no.3
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    • pp.362-378
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    • 1999
  • This study is to investigate sex role identity and health behavior among university students in Seoul, during the late of 1999. The instruments for data obtainment were KSRI of Kim(1994), and Health Style : A Self-Test provided by ODPHP National Health Information Center. These instrument were reliable, showing Cronbach $\alpha$ .98 and .77. Frequency, t-test, $x^2$-test, stepwise regression were conducted for data analysis, using SAS 6.12 program. The major findings were as follows : 1. For female student. Androgeny(34.0%)type was most common and subjects of feminity type were 28.7%. In contrast, Masculinity type(41.8%) was most prevalent. and undifferentiated type was 30.1% among male students. There were significant difference between male and female student in the type of sex role identity. 2. 89.6% of all subjects were included in risk group for exercise and physical activity, 86.4% for diet habit, 43.2% for alcohol drinking and drug use, 35.6% for stress control, 32.8% for safety behavior, 24.8% for smoking. The big health risk behavior problem of male students were smoking, drinking, diet habit, and exercise. The important health risk behavior problem were diet habit and exercise. There were significant difference in smoking, drinking, exercise between sex. 3. Analysis of the distribution by sex role identity type and health behavior revealed that subjects who were undifferentiated typed group had high risk behavior in stress control, safety, exercise, drinking. Smoking and drinking were more problematic for masculinity typed group had high risk behavior in diet and exercise. The data showed that androginy typed group had more healthy behavior, compared with other sex role identity typed group for all of health behavior. Further research is need to understand the role of sex role identity in health behavior, the variables associated with them. And sex role identity has to be considered in research and practice about health promotion.

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Development of Speech Recognition System based on User Context Information in Smart Home Environment (스마트 홈 환경에서 사용자 상황정보 기반의 음성 인식 시스템 개발)

  • Kim, Jong-Hun;Sim, Jae-Ho;Song, Chang-Woo;Lee, Jung-Hyun
    • The Journal of the Korea Contents Association
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    • v.8 no.1
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    • pp.328-338
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    • 2008
  • Most speech recognition systems that have a large capacity and high recognition rates are isolated word speech recognition systems. In order to extend the scope of recognition, it is necessary to increase the number of words that are to be searched. However, it shows a problem that exhibits a decrease in the system performance according to the increase in the number of words. This paper defines the context information that affects speech recognition in a ubiquitous environment to solve such a problem and develops user localization method using inertial sensor and RFID. Also, we develop a new speech recognition system that demonstrates better performances than the existing system by establishing a word model domain of a speech recognition system by context information. This system shows operation without decrease of recognition rate in smart home environment.

Analyses on Nutritional and Behavioral Risk Factors of Atopic Dermatitis (AD) in Korean Preschoolers (학령 전 아동에서 아토피피부염의 영양.행동 위험 요인 분석)

  • Shin, Kyung-Ok;Park, Hyun-Suh;Oh, Se-Young
    • Journal of Nutrition and Health
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    • v.39 no.8
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    • pp.795-800
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    • 2006
  • In order to examine nutritional and behavioral risk factors of atopic dermatitis (AD) in Korean preschoolers, we analyzed data on 144 children aged 3-6 years with AD and their 434 healthy counterparts. The data included breast-feeding history, current weight, food behaviors assessed by the Mini Dietary Assessment (MDA), food intake by a semi-quantitative food frequency questionnaire, and behavior problems by the Preschool and Kindergarten Behavior Scale (PKBS). Multivariate logistic regression analyses were performed after controlling for preschool location and child's age, gender and total energy intake, as appropriate. There was no group difference of child and household characteristics. Breastfeeding history was related to lower AD risk (OR = 0.63, 95% Cl = 0.40-0.99), yet no statistically significant association was found with overweight status. Regarding food behaviors, AD risk was lower in children who drank milk at least one cup per day (OR = 0.52, 95% Cl = 0.35-0.78) and had regular meals (OR = 0.62, 95% Cl =0.42-0.92). Moreover, there were lower risks of AD in the second (OR =0.48, 95% Cl = 0.28-0.82) and the highest (OR = 0.55, 95% Cl = 0.32-0.94) intake quartiles as compared with the lowest quartile of kimchi intake. Similarly, AD risk was lower in the highest quartile of rice (OR = 0.51 Cl = 0.28-0.93) and the second quartile of fruit (OR =0.45, 95% Cl = 0.25-0.82) intakes. AD children had more problems in social interaction (OR = 1.97,95% Cl = 1.26-3.07) and independence (OR = 1.60, 95% Cl = 1.01 -2.54) measures than the healthy controls. Likewise, AD children tended to show more problem behaviors such as anxiety (OR = 1.63, 95% Cl = 0.99-2.69). Our results suggest that nutritional and behavioral dimensions are related to AD risk, yet the case control study design may preclude generalization of these results.

A Multicasting based Efficient Control Message Transmission for Quality of Service in Asymmetric 10G-EPONs (비대칭적인 10G-EPON망에서 QoS 제공을 위한 멀티캐스트 기반 효과적인 제어 메시지 전송 방법)

  • Yang, Yeon-Mo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.5B
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    • pp.771-776
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    • 2010
  • In this paper, we present an efficient centralized dynamic bandwidth allocation scheme with multicasting for asymmetric 10G-Ethernet Passive Optical Networks (10G-EPONs). The proposed scheme is based on multicast-burst polling and provides quality of service (QoS) with class of service (CoS) to different lasses of packets. It is shown that a well-known conventional interleaved polling scheme severely decreases downstream channel capacity for user traffic when the upstream network load is low (avalanche gate frequency). To overcome this problem, we have proposed a multicast burst polling scheme which shows impressively lower downstream bandwidth consumption compare to IPACT and moreover it did not show the light load penalty problem. Simulation results using an OPNET tool show that the multicast burst polling effectively eliminates light-load penalty and minimizes downstream bandwidth consumption under avalanche gate frequencies.

An effect of the parent's achievement pressure on the youth group's stress (부모의 성취압력이 청소년의 스트레스에 미치는 영향)

  • Jou, Hye-Mee;Kim, Sung-Sil;Lim, Hye-Kung;Han, Sung-Hyun;Song, Mi-Ra;Son, Bu-Soon
    • Journal of environmental and Sanitary engineering
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    • v.22 no.1 s.63
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    • pp.67-74
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    • 2007
  • The purpose of this study is to provide the necessarily basic data of the ideal growth of the students by investigating the effect of the student's stress due to the parent's achievement pressure. The sample of this study are In students consisting of 51 boys and 49 girls in the 3rd grade classes of "J" middle school located in Siheung city, Kyungki-do. The observed materials are used to investigate the parent's achievement pressure and the level of stress. Based on the observed data, the frequency, correlation, and t-test have been gained. The results are summarized as follows : 1. The perception of the parent's achievement pressure is shown more by the boy's achievement pressure($44.2{\pm}9.9$) than the girl's achievement pressure($39.939{\pm}11.089$), among the high level students. 2. The perception of the parent's achievement pressure is shown more the high($43.0{\pm}10.7$) and middle($42.9{\pm}11.8$) level students than the low($39.7{\pm}8.00$) level students. 3. The stress of male students was high in the Solving Problem stress factor with by the mean of $15.1{\pm}3.7$, and the stress of female students was high in the Self-Control stress factor with the mean of $13.3{\pm}3.9$. 4. The stress of high, middle, low level student was high in the Solution of Matter stress factor with the mean of $14.2{\pm}3.9$. 5. The results were the main cause of the stress than the parent's achievement pressure.

Analysis of Technical Problem for Soil Compaction by Gyratory Compactor (선회다짐기를 이용한 흙의 다짐시 기술적 문제 분석)

  • Lee, Kwan-Ho;Jang, Tae-Young
    • Journal of the Korean Society of Hazard Mitigation
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    • v.10 no.1
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    • pp.43-48
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    • 2010
  • Proctor test A or D method of compaction is the most common laboratory test for investigation of subgrade soil characteristics, however, compression type using roller is used in the field. The differences between laboratory and field compaction have considerable error as application to subgrade soil properties of laboratory test. The investigation of compacted soil is carried into effect to solve the problem. The gyratory compactor which is made to reproduce the field density of asphalt mixture, coming from traffic loads, has an advance to compact it similar to arrangement of field aggregate particles. This gyratory compactor has several problems of investigation of compacted soil, because it has designed to make initial asphalt specimens. The main objectives of this research are grasping problems when compacted soil test using the gyratory compactor and showing solutions. It has made a comparative study of difference of the percentage of water content and weight, which are before and after compaction, about the pressure of compaction, frequency of compaction and speed of compaction. And it also has investigated finding maximum percentage of water content which not occur change of percentage of water content after compaction and searching how has an effect on drawing compaction curve.

Rainfall analysis considering watershed characteristics and temporal-spatial characteristics of heavy rainfall (집중호우의 시·공간적 특성과 유역특성을 고려한 강우분석 연구)

  • Kim, Min-Seok;Choi, Ji-Hyeok;Moon, Young-Il
    • Journal of Korea Water Resources Association
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    • v.51 no.8
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    • pp.739-745
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    • 2018
  • Recently, the incidence of heavy rainfall is increasing. Therefore, a rainfall analysis should be performed considering increasing frequency. The current rainfall analysis for hydrologic design use the hourly rainfall data of ASOS with a density of 36 km on the Korean Peninsula. Therefore, medium and small scale watershed included Thiessen network at the same rainfall point are analyzed with the same design rainfall and time distribution. This causes problem that the watershed characteristics can not be considered. In addition, there is a problem that the temporal-spatial change of the heavy rainfall occurring in the range of 10~20 km can not be considered. In this study, Author estimated design rainfall considering heavy rainfall using minutely rainfall data of AWS, which are relatively dense than ASOS. Also, author analyzed the time distribution and runoff of each case to estimate the huff's method suitable for the watershed. The research result will contribute to the estimation of the design hydrologic data considering the heavy rainfall and watershed characteristics.