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A Research on the Improvement of Visibility Using Low Deck Lighting in Bad Weather (악천후 시 낮은 도로조명을 이용한 도로 시인성 향상에 대한 연구)

  • Nam, Ki Ho;Kim, Chung Hyeok;Nam, Ki Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.33 no.3
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    • pp.186-193
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    • 2020
  • We investigate a fog-detection CCT control system using low deck lighting as a solution to the forward visibility of pole-type street lamps employed on existing roads. The lighting standards were met with a light source that has less compared with those of pole-type street lamps. The results show that the transmission rate was increased by changing the color temperature by automatically recognizing fog in bad weather and minimizing the phenomenon of lighting. In addition, it was allowed to create a safer and more comfortable driving environment for drivers owing to flicker or light pollution of existing pole-type street lamps. As a result, if lighting is used at a lower level than pole-type street lamps, the accident rate caused by securing the driver's forward visibility can be reduced sharply and existing problems can be resolved.

An Introduction to Speed Control System of Small Steam Turbine for Feed Water Supply in Power Plant (발전소 급수펌프 구동용 소형 터빈 제어시스템 소개)

  • Choi, In-Kyu;Kim, Jong-An
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1603-1604
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    • 2007
  • The load of power plants changes every from time to time according to which steam flow of boiler changes. the feed water control is very important for the power plant to be operated in its stability conditions. In case of circulation type boiler, the instability of feed water control leads to instability of drum level control. The higher level of drum water can induce bad quality steam to go into turbine which means the possibility of damage. The lower level of drum water can induce the tubes of boiler water wall to be overheated. In case of once through type boiler, the instability of feed water control leads to bad cooling of superheaters. The less the feed water flow is, the more heated the superheater is. It is necessary for the turbine driving feed water pump to be controlled for the optimal feed water flow in the large capacity power plant. The speed of turbine is controled for the feed water flow. By the way, the optimal control of steam valve is necessary for the speed control of turbine. Therefore, the various kinds of the steam valve structures are introduced in this paper

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A SELECTION PROCEDURE FOR GOOD LOGISTICS POPULATIONS

  • Singh, Parminder;Gill, A.N.
    • Journal of the Korean Statistical Society
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    • v.32 no.3
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    • pp.299-309
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    • 2003
  • Let ${\pi}_1,...,{\pi}_{k}$k($\geq$2) independent logistic populations such that the cumulative distribution function (cdf) of an observation from the population ${\pi}_{i}$ is $$F_{i}\;=\; {\frac{1}{1+exp{-\pi(x-{\mu}_{i})/(\sigma\sqrt{3})}}},\;$\mid$x$\mid$<\;{\infty}$$ where ${\mu}_{i}(-{\infty}\; < \; {\mu}_{i}\; <\; {\infty}$ is unknown location mean and ${\delta}^2$ is known variance, i = 1,..., $textsc{k}$. Let ${\mu}_{[k]}$ be the largest of all ${\mu}$'s and the population ${\pi}_{i}$ is defined to be 'good' if ${\mu}_{i}\;{\geq}\;{\mu}_{[k]}\;-\;{\delta}_1$, where ${\delta}_1\;>\;0$, i = 1,...,$textsc{k}$. A selection procedure based on sample median is proposed to select a subset of $textsc{k}$ logistic populations which includes all the good populations with probability at least $P^{*}$(a preassigned value). Simultaneous confidence intervals for the differences of location parameters, which can be derived with the help of proposed procedures, are discussed. If a population with location parameter ${\mu}_{i}\;<\;{\mu}_{[k]}\;-\;{\delta}_2({\delta}_2\;>{\delta}_1)$, i = 1,...,$textsc{k}$ is considered 'bad', a selection procedure is proposed so that the probability of either selecting a bad population or omitting a good population is at most 1­ $P^{*}$.

A Study on Applicability of Citrus Sludge for the Manufacture of Corrugated Medium (골심지 제조를 위한 감귤 착즙 슬러지의 적용성 평가)

  • Lee, Tai-Ju;Kim, Hyoung-Jin;Lee, Chang-Yong
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.42 no.5
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    • pp.47-53
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    • 2010
  • It is important to utilize the citrus sludge in terms of the reuse of waste materials in the manufacture of corrugated medium. Especially, the mandarin industry occupies the first place in Jeju province. In this paper, the application of citrus sludge mixed with KOCC recycled fibers into the manufacture of corrugated medium was studied. The citrus sludge was acidic in pH value. Also, the constituents of citrus sludge contain some short fibers, fines, and mucus which contain flavonoids, pectins and so on. In papermaking application, these components cause some troubles like foams, bad smell, fouling on the paper machine, and bad drainage and web breaks of wet web. The strength properties of handsheets prepared from KOCC and citrus sludge was decreased, compare to handsheets made of only KOCC. To compensate the problems on strength properties, some kinds of additives were tried to apply into papermaking wet-end system in laboratory scale. As a result, mixing conditions of alum, starch and anionic additives showed the best options in the recovery of strength properties and formations of corrugated medium.

A Study on the Forming Failure Inspection of Small and Multi Pipes (소형 다품종 파이프의 실시간 성형불량 검사 시스템에 관한 연구)

  • 김형석;이회명;이병룡;양순용;안경관
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.11
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    • pp.61-68
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    • 2004
  • Recently, there has been an increasing demand for computer-vision based inspection and/or measurement system as a part of factory automation equipment. Existing manual inspection method can inspect only specific samples and has low measuring accuracy as well as it increases working time. Thus, in order to improve the objectivity and reproducibility, computer-aided analysis method is needed. In this paper, front and side profile inspection and/or data transfer system are developed using computer-vision during the inspection process on three kinds of pipes coming from a forming line. Straight line and circle are extracted from profiles obtained from vision using Laplace operator. To reduce inspection time, Hough Transform is used with clustering method for straight line detection and the center points and diameters of inner and outer circle are found to determine eccentricity and whether good or bad. Also, an inspection system has been built that each pipe's data and images of good/bad test are stored as files and transferred to the server so that the center can manage them.

Design Parameters of Optical Pickup Actuator for the Next Generation (차세대 광 픽업 구동기를 위한 설계 변수)

  • Han, Chang-Soo;Kim, Soo-Hyun
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.1
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    • pp.82-88
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    • 2001
  • The demands of high data transfer rate and high recording density in optical disk memory device are being increased. In this paper, 4 design parameters for next generation optical disk are investigated. As for the high data transfer rate, two design parameters such as driving acceleration and transmissibility are introduced. As the high recording density is concerned, the minimum linearity and the tilt of the actuator are introduced. Two kinds of pickup actuator are used to evaluate the validity of the parameters through the simulation and the experiment. The 4-wire actuator has good linearity but bad stability and tilt characteristics, while the rotary and axis actuator has good stability for the external vibration but bad linearity. It is demonstrated that the newly proposed design parameters are available to design and evaluate quantitatively the performance of the actuator for the next generation optical disk.

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A Study on Eating Habit of Elementary School Students in Higher Grade (초등학교 고학년 학생의 식습관에 관한 조사 연구 - 서울지역 일부 초등학교를 중심으로 -)

  • Kim Eun-Young;Park Hong-Hyun
    • The Korean Journal of Food And Nutrition
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    • v.17 no.4
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    • pp.393-404
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    • 2004
  • The purpose of this study was to provide basic data of nutrition education to teach the right eating habit and lifestyle by investigating eating habit of students in private and public elementary schools of Kangnam and Kangbuk region. When the eating habit was investigated, there was no difference between the residential region, and school types. Depending on gender and person who cooked, there was meaningful difference in the eating habit. When the mother or father cooked for the student, his or her child had breakfast everyday, had a meal regularly, enjoyed the meal with the family, and left less food. This shows that the meal with family is a very positive factor in the formation of right eating habit. The female students tend to eat snacks, skip breakfast, have unbalanced diet, leave food, and watch TV during a meal more than the male students. Therefore, the female students need more education of eating habit. Also, not many the students usually got corrected their bad eating habits from others, and this showed that no proper guidance of their bad eating habits was done. Nevertheless, the students tried to correct their eating habits by themselves. If the schools and students' give them the proper education about eating habit, it can be more effective. Therefore, the school should teach the students and their parents the right table manner and nutrition information through a systematical curriculum. In special cases, they should teach the students individually.

Adaptive Reconstruction of Harmonic Time Series Using Point-Jacobian Iteration MAP Estimation and Dynamic Compositing: Simulation Study

  • Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.24 no.1
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    • pp.79-89
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    • 2008
  • Irregular temporal sampling is a common feature of geophysical and biological time series in remote sensing. This study proposes an on-line system for reconstructing observation image series contaminated by noises resulted from mechanical problems or sensing environmental condition. There is also a high likelihood that during the data acquisition periods the target site corresponding to any given pixel may be covered by fog or cloud, thereby resulting in bad or missing observation. The surface parameters associated with the land are usually dependent on the climate, and many physical processes that are displayed in the image sensed from the land then exhibit temporal variation with seasonal periodicity. A feedback system proposed in this study reconstructs a sequence of images remotely sensed from the land surface having the physical processes with seasonal periodicity. The harmonic model is used to track seasonal variation through time, and a Gibbs random field (GRF) is used to represent the spatial dependency of digital image processes. The experimental results of this simulation study show the potentiality of the proposed system to reconstruct the image series observed by imperfect sensing technology from the environment which are frequently influenced by bad weather. This study provides fundamental information on the elements of the proposed system for right usage in application.

A Study of Edge Detection for Auto Focus of Infrared Camera

  • Park, Hee-Duk
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.1
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    • pp.25-32
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    • 2018
  • In this paper, we propose an edge detection algorithm for auto focus of infrared camera. We designed and implemented the edge detection of infrared image by using a spatial filter on FPGA. The infrared camera should be designed to minimize the image processing time and usage of hardware resource because these days surveillance systems should have the fast response and be low size, weight and power. we applied the $3{\times}3$ mask filter which has an advantage of minimizing the usage of memory and the propagation delay to process filtering. When we applied Laplacian filter to extract contour data from an image, not only edge components but also noise components of the image were extracted by the filter. These noise components make it difficult to determine the focus state. Also a bad pixel of infrared detector causes a problem in detecting the edge components. So we propose an adaptive edge detection filter that is a method to extract only edge components except noise components of an image by analyzing a variance of pixel data in $3{\times}3$ memory area. And we can detect the bad pixel and replace it with neighboring normal pixel value when we store a pixel in $3{\times}3$ memory area for filtering calculation. The experimental result proves that the proposed method is effective to implement the edge detection for auto focus in infrared camera.

A Study of Experiences of Smoking and Smoking Cessation in out-of-school Youth (학교 밖 청소년의 흡연 및 금연 경험 연구)

  • Park, Min Hee;Yim, So Youn
    • Journal of Korean Public Health Nursing
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    • v.32 no.3
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    • pp.388-399
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    • 2018
  • Purpose: The aim of this qualitative study was to identify the experiences of smoking and smoking cessation in out-of-school youth. Methods: The participants were 12 out-of-school youths belonging the Youth support Center located in A and B area. The data were collected from January 8 to 15, 2018, using a FGI(Focus Group Interview). The main sub-domains of the experiences of smoking and smoking cessation in out-of-school youth by 7 questions were categorized from the intrapersonal, interpersonal, organizational, and community factors in ecological model. Results: The motivation, continuity, disadvantage of smoking experiences of out-of-school youth were analyzed in 10 sub-domains (curiosity, friend's invitation, mood of adapted group, habit, relieving stress, providing breaks, friendship, physical damage, loss of money, a bad sight of smoker). The reason, difficulty, advantage, reason for restarting smoking cessation experiences of out-of-school youth were analyzed in 15 sub-domains (physical damage, for future hope, invitation of others, influence of family, weight gain, emotional stress, worsening friendship, improvement physical condition, saving money, better relationships, not with bad friends, withdrawal, smoking of friends, drinking, separated a lover). Conclusion: Based on the results, it is expected that a Specialized Smoking Cessation Education Program will be developed for out-of-school youth's health activities in ecological factors.