• Title/Summary/Keyword: Reliability design

Search Result 5,451, Processing Time 0.03 seconds

Study on Local Wireless Network Data Structure for Sludge Multimeter (슬러지 멀티미터를 위한 근거리무선네트워크 데이터구조 설계 연구)

  • Jung, Soonho;Kim, Younggi;Lee, Sijin;Lee, Sunghwa;Park, Taejun;Byun, Doogyoon;Cha, Jaesang
    • Journal of Satellite, Information and Communications
    • /
    • v.9 no.2
    • /
    • pp.96-100
    • /
    • 2014
  • Recently, the management system of wastewater treatment facility has magnified due to the stringent regulations for the protection of the environment, and a sewage treatment plant efficiency and research of the car development are activated in large facilities or industrial park. however, the existing sewerage disposal system and specific water quality monitoring network reliability for real-time transmission of this building is insufficient. In this paper, we proposed a local wireless network design for sludge multi meter data collection and control for measuring the concentration of the sludge efficiently. Also, the collected data over the local wireless network to transmitted to the central monitoring system and accumulate the data in real time to calculate statistics is possible to monitor the status of the sewage treatment facilities. The proposed system uses a short-range wireless networks of IEEE 802.15.4 and configures an IEEE 802.11 network which can monitor real-time status in central system. Also, we install a sludge multimeter and communication network in sewage treatment facilities and confirm the usefulness of the proposed technique by demonstrating its effectiveness.

A Basic Study on Sorting of Black Plastics of Waste Electrical and Electronic Equipment (WEEE) (폐가전의 검정색 플라스틱 재질선별에 관한 기초 연구)

  • Park, Eun Kyu;Jung, Bam Bit;Choi, Woo Zin;Oh, Sung Kwun
    • Resources Recycling
    • /
    • v.26 no.1
    • /
    • pp.69-77
    • /
    • 2017
  • Used small household appliances(small e-waste) consists of a variety of complex materials and components. The small e-waste is mainly composed of plastics and an important potential source of waste plastic. The black plastics, particularly are very difficult to separate by resin type and therefore these are mainly recycled in the form of a mixtures. In the present study, the sorting technologies such as gravity and electro static separation, near-infrared ray(NIR) and IR/Raman optical sorting separation on mixture of black plastics were analyzed and their limitations on sorting process were also investigated. The Laser Induced Breakdown Spectroscopy(LIBS) spectrum of each black plastics was used for identification of black plastics by resin type, and after analyzing the normalization operation, Principal Component Analysis(PCA) was carried out. The spectrum data was optimized through PCA process. In order to improve the identification accuracy and sorting efficiency of black plastics, it is necessary to design a classifier with high efficiency and to improve the performance and reliability of the classifier by applying the field of intelligent algorithms.

A Study on Use Satisfaction and Image Evaluation of User through Post Occupancy Evaluation in Urban Park - On the 2·28 Memorial Park in Daegu - (도심공원 이용 후 평가를 통한 이용 만족도와 이미지 평가 - 대구 2·28기념중앙공원을 대상으로 -)

  • Koo, Min-Ah;Eom, Boong-Hoon;Han, Ye-Seo
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.46 no.4
    • /
    • pp.11-20
    • /
    • 2018
  • This paper deals with Post Occupancy Evaluation (POE) of 2.28 Memorial Park in Daegu. The park is located in center of the city. The results and discussions could be used as basic data for urban park planning and design, in CBD. A questionnaire was conducted for 15 days from May 11, to May 26, 2016, and a sample group consisting of 230 on site users. The behavior, satisfaction, and preference of space image, were surveyed. The behavior analysis, satisfaction, and image evaluation questionnaire were derived using previous studies, and reliability, factor analysis and multiple regression analysis were conducted using SPSS. As a result, the items were very reliable, causal factors were extracted, and the variables that affect satisfaction and image preference were able to be identified. In the 2.28 Memorial Park, user satisfaction and image evaluation value were very high in most items. As a result of the assessment, the green-water landscape factors and cleanness factors, which have the greatest influence on satisfaction and preference, should be continuously maintained. Due to the characteristics of the city center parks, the users of the parks also felt environmental problems in the urban areas, so the users assessed noise levels, plant species, and air quality at a low level. Therefore, to solve this, plans such as noise abatement and extension of green space should be ongoing.

FMECA Procedure for Failure Analysis of Train High-Speed Circuit Breaker (전동차 고속차단기 고장 분석을 위한 FMECA 기법)

  • Kim, Sung-Ryeol;Moon, Yong-Sun;Choi, Kyu-Hyoung
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.16 no.5
    • /
    • pp.3370-3377
    • /
    • 2015
  • FMECA(Failure Mode, Effects and Criticality Analysis) techniques to make quantitative evaluation of failure effects severity and criticality have been applied to systematic failure analysis for reliability improvement of train which should provide regular service and secure high level of safety as a mass transportation system. These FMECA techniques do not fully reflect the inherent train operation and maintenance circumstances because they are based on the FMECA standards devised for other industries such as automobile industry and FMECA standard dedicated to train industry has not been established yet. This paper analyzes FMECA standards for various industries, and suggests a FMECA technique dedicated to train industry which makes failure effect analysis and criticality analysis step by step and makes criticality analysis placing emphasis on the severity of the failure effect. The proposed technique is applied to FMECA of high-speed current breaker which is a core safety device of train using field failure data for 15 years of train maintenance. The FMECA results show that breakage of arc chute has the highest risk with 3rd severity class and 5th criticality class among all the components of high-speed circuit breaker. Damage and poor contact of electronic valve, and cylinder breakage with 3rd severity class and 4th criticality class are followed by. These results can be applied to improvement of design and maintenance process for high-speed circuit breaker of train.

The Estimation of Friction Velocity in an Open Channel by the Entropy Concept (엔트로피 개념을 활용한 개수로 마찰속도 산정)

  • Choo, Tai Ho;Son, Hee Sam;Yun, Gwan Seon;Noh, Hyun Seok;Ko, Hyun Soo
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.16 no.2
    • /
    • pp.1533-1540
    • /
    • 2015
  • In order to demonstrate the flow properties of the river bed and the design of hydraulic structures, the estimation of friction velocity is essentially required. However, existing friction velocity equations such as Log method and Power law have trouble to estimate the friction velocity because a boundary condition and various hydraulic properties are changed constantly in near the wall. In the present study, therefore, a new friction velocity equation that can minimize the parameters and reduce an error was suggested. To verify accuracy and reliability for the proposed equation, Clauser method, $\sqrt{gRI}$ method, reynolds stress method by Dr. Song were compared with the proposed method by estimated entropy parameter M for each channel. Consequently, the results show that uniform flow condition as well as non-uniform flow condition with highly accuracy nearly matched in case of accelerating non-uniform condition of $R^2=0.9621$, Decelerating Non Uniform condition of $R^2=0.9274$, Uniform condition of $R^2=0.8865$.

Application of the Theory of Planned Behavior and the Theory of Reasoned Action to Predicting Cervix Cancer Screening Behavior (자궁암 조기검진행태 예측을 위한 계획된 행동이론과 이성적 행동이론의 적용)

  • Kim, Yong-Ik;Kim, Chang-Yup;Shin, Young-Soo;Lee, Kun-Sei
    • Journal of Preventive Medicine and Public Health
    • /
    • v.34 no.4
    • /
    • pp.379-388
    • /
    • 2001
  • Background : Cervix cancer is the most common form of cancer among Korea women. in spite of proof that cervical cancer screening could reduce death rates substantially, the screening rates reported by previous Korean studies remain stubbornly very low. Behavioral studies to increase the cervix cancer screening rate are essential in order to develop the cancer screening program. Objective : To evaluate the factors which are related to the intention and behavior for cervix cancer screening using the Theory of Planned Behavior (TPB) and the Theory of Reasoned Action (TRA). Methods : The survey was conducted from July 21 st to 26th in 1998. Of 3,218 women, 303(12.2%) between 30 and 55 years old, voluntarily participated in the survey in the 3 Myeons in Choongju city. Charge-free cervix cancer screening was provided for the subjects 3 months later. Results : The R-square of both TPB and TRA to the intention (30% and 42%, respectively) was greater than the actual behavior (21% and 13%, respectively. TPB and TRA were found to provide an appropriate framework for the study of cervix cancer screening behavior. However, TRA was more powerful in explaining the intention, not only because the perceived behavioral control component exhibited lower reliability and validity than other components(altitude and subjective norm), but also because there may have been a few limitations in this study design. Consequently, the use of TRA is preferred in attempting to explain intention and actual behavior in this study. Conclusions : This study suggests that a successful intervention program should focus on changing attitudes and reducing psychologic barriers, rather than on just providing information. Physician recommendations, and the support of family members and friends are also very important factors in cervix cancer program participation. Physicians, friends, family members, and opinion leaders in rural areas, all of whom could affect the individual subjective norm, may all have the potential to play great roles as facilitators.

  • PDF

A Study on the Factors Affecting the Use and Satisfaction of Internet Ticketing Systems (인터넷 티켓팅 시스템의 사용과 만족에 영향을 미치는 요인)

  • Woo, Sung-Hwa;Kim, Kyung-Kyu;Chang, Hang-Bae;Shin, Ho-Kyoung
    • Asia pacific journal of information systems
    • /
    • v.17 no.3
    • /
    • pp.1-24
    • /
    • 2007
  • With the development of information technology (IT), various information systems (IS) such as Web-based systems and mobile systems have appeared utilizing different technologies. However, recent studies on IS use and user satisfaction rarely account for technological differences among IS and environmental characteristics where IS are intended to be used. The purpose of this research is to investigate the determinants of the use of Web-based ticketing systems for cultural activities and to empirically validate their relationships. Environmental psychology suggests that human beings respond to external stimuli from environments with their emotions, and their emotional states influence human actions, e.g., IS use in this research. Applying environmental psychology to the use of Web-based systems in the culture and entertainment industry, we propose that web site characteristics first influence a user's internal state of mind (i.e., flow) and then the flow state influences the IS use. Studies related to the state of flow collectively affirm the key role played by the flow construct in shaping individual attitudes and behaviors toward IS. Users' flow states are captured by their shopping enjoyment, perceived behavioral control, and the level of concentration on the IS use. Referring to social presence theory, we have included such web site characteristics as content quality, context of web site, and community quality. In our research model, a second order construct is utilized to represent web site quality, because flow theory suggests that holistic experiences with web-based systems (rather than individual characteristics of the web site) are important in explaining the IS use. Further, we have included trust as another important factor influencing the IS use since business transactions on the web encompass higher uncertainty comparing to offline transactions. In order to test our hypotheses, we have conducted an online survey which results in 1,141 valid responses in the final sample. The data were collected from respondents who have experiences in Internet ticketing systems. Although it was a convenient sample, the sample represents a wide variety of user demographics. Validity and reliability of the research instrument were tested and research hypotheses were examined using PLS Graph 3.0. The results indicate that web site characteristics significantly influence the level of user concentration, user's enjoyment in shopping, and perceived behavioral control. Further, the use of Internet ticketing systems is influenced by users' flow states and trust in the web channel. User satisfaction is turned out to be affected by the use of Internet ticketing systems. Unlike extant research on the relationship between web site characteristics and its use, our study has found that, in the culture and entertainment industry, the impact of web site characteristics on IS use is mediated by a user's flow state. This finding has a practical implication that web site design should include as many features that enhance shopping enjoyment and concentration. Other practical implications of these findings and future research implications are also discussed.

Steady-state Thermal Analysis of 5 kW IPMSM Using Thermal Equivalent Circuit (열등가회로를 이용한 5 kW 급 영구자석 동기전동기의 정상상태 열 특성 해석)

  • Kim, Tae Hyun;Yoo, Young Bum;Na, Jong Seung;Ryu, Kyongtae;Moon, Yoon Jae;Lee, Jae Heon;Lee, Ju;Park, Chan Bae;Moon, Seung Jae
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.38 no.11
    • /
    • pp.951-956
    • /
    • 2014
  • Steady-state thermal analysis was performed on a thermal equivalent circuit to determine the heat generation during operation of an interior permanent magnet synchronous motor (IPMSM). New machines must be compact and light and produce high torque density under extreme environmental conditions. Thermal analysis of an IPMSM is particularly important because excessive heat generated from the core and magnet reduces the IPMSM's output and has adverse effects on the durability. Therefore, steady-state thermal analysis of an IPMSM was performed for changes in the design variables using a thermal equivalent circuit. The changed variables were the axis length and thickness of the housing. The results of this method were compared with those of the finite element method to verify the accuracy and reliability.

Design and Implementation of the Management System of Cultivation and Tracking for Agricultural Products using USN (유비쿼터스 센서 네트워크를 이용한 농산물 재배관리 및 이력추적 시스템의 설계 및 구현)

  • Yoo, Nam-Hyun;Song, Gil-Jong;Yoo, Ju-Hyun;Yang, Su-Yeong;Son, Cheol-Su;Koh, Jing-Wang;Kim, Won-Jung
    • Journal of KIISE:Computing Practices and Letters
    • /
    • v.15 no.9
    • /
    • pp.661-674
    • /
    • 2009
  • Recently, there has been much research and many attempts to enhance converged information technology services using new technology such as ubiquitous sensor networks (USN) in medical, environmental, industrial, and logistic areas. There has also been much research and various attempts to apply this new technology to agricultural areas. However, applications to the agricultural areas should be considered differently against the same areas such as medical, environmental, industrial, and logistics. Therefore, this paper suggests that an agricultural cultivating management and traceability system. This system is a unified system that supports the processes sowing seeds through selling agricultural products to consumers. Farmers can be provided with an effective calendar for cultivation and weather information in real time as well as the monitoring of the growth of farm products on the farm in real time using this system. Farmers can also control all equipment installed on the farm directly or remotely and the equipment can be controlled automatically when the measured values such as temperature and humidity deviate from the decent criteria which are set by farmers or this system. Additionally, the reliability for and the better quality of the agricultural products can be improved because farmers can use this unified system to cover all processes from sowing seeds to selling to consumers.

Study on Relationship Between Consumption Values of Masstige and Consumer Happiness (매스티지 브랜드의 소비가치와 소비자 행복과의 관계에 관한 연구)

  • Kim, Yu-Kyung
    • Journal of Distribution Science
    • /
    • v.13 no.1
    • /
    • pp.105-118
    • /
    • 2015
  • Purpose - The objective of this study is to verify whether there are differences between Korean and Chinese consumers in the importance of the attributes such as shopping value and loyalty in social commerce. With the purpose of finding out these differences, the following questions are set up as research questions. First, will there be a difference between Korea and China in the importance of attributes of social commerce? Second, will there be a difference between Korean and Chinese consumers in shopping value? Third, will there be a difference between Korean and Chinese consumers in their loyalty? Research design, data, and methodology - The researchers collected data through self-administered questionnaires from Korean and Chinese consumers who had used social commerce within the past six months before answering the questionnaire. First, for social commerce users in Korea, comprising male and female university students in Chungcheong, a questionnaire was circulated. For social commerce users in China, university students within Beijing were surveyed. Responses to 336 questionnaires were used, excluding those with no answers or unreliable answers. Data coding and data cleaning were used. SPSS 18.0 was used. First, exploratory factor analysis is done to verify the validity of testing tools, and Cronbach's α coefficient is used to verify credibility. For factor analysis, the Varimax method is used. To verify the internal consistency reliability of each factor, the Cronbach's α coefficient is used to verify the credibility. Second, a T-test is done to verify differences between Korean and Chinese consumers for the importance of attributes. Third, ANOVA (Analysis of variance) is done to verify differences between Korean and Chinese consumers in shopping value and loyalty. Results - When Korean and Chinese consumers use social commerce, first, the importance of the attributes of social commerce is affected by four factors; playfulness and economic factors are more important to Korean consumers than Chinese consumers. As for informativeness factors, including product information and quality, and buyer comments, there was no confirmed difference between Korean and Chinese consumers. The convenience factor is more important to Chinese consumers than Korean consumers. Second, the factors affecting shopping value for Korean and Chinese consumers were hedonic shopping value and rational shopping value. To see the difference between Korean and Chinese consumers in shopping value factors, a t-test is conducted. As a result, in the rational shopping value factors of social commerce, Korean consumers scored higher than did Chinese consumers. These results were verified to be meaningful through statistics. In the hedonic shopping value factor of social commerce, Korean consumers scored higher than Chinese consumers. These results showed a significant difference. Third, loyalty in social commerce is higher for Chinese consumers than for Korean consumers. However, there is no difference in loyalty depending on sex. Conclusions - These results will hopefully be valuable and used in the future by Korean companies that wish to enter the Chinese social commerce market.