• 한국정보통신학회논문지
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• 제12권12호
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• pp.2265-2270
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• 2008

최근 대두 되고 있는 지구 온난화 및 기후 변화와 관련해서 수온이 해양 생태계에 미치는 영향을 알기 위하여 한반도 주변 해역을 중심으로 $1988{\sim}2000$년까지 NOAA SST자료를 활용하여 어류 회류의 변동성에 대하여 조사하였다. 위성자료를 분석해 본 결과 우리나라는 전반적으로 온난화 경향이 나타나고 있다. 연근해의 수온상승과 비교해 볼 때, 오징어, 멸치, 정어리, 꽁치 등 회유성 어종의 분포해역이 점차 북상하고 있는 것으로 나타났다. 또한 난류성 어종인 오징어와 멸치의 어획량은 증가한 반면, 한류성 어종인 꽁치와 정어리는 감소하는 경향을 보였다. 그러나 어황에 영향을 미치는 요인에는 수온뿐만 아니라 염분 및 오염도 등 여러 가지 요소가 존재하기 때문에 수온상승으로 인해 생기는 어황의 변화라고 단정 짓기는 어렵다. 따라서 금후 기후 변동과 연근해 어황 변화에 대해서도 계속적인 연구가 필요하다.

• 산업경영시스템학회지
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• 제46권2호
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• pp.152-159
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• 2023

Due to COVID-19, changes in consumption trends are taking place in the distribution sector, such as an increase in non-face-to-face consumption and a rapid growth in the online shopping market. However, it is difficult for small and medium-sized export sellers to obtain forecast information on the export market by country, compared to large distributors who can easily build a global sales network. This study is about the prediction of export amount and export volume by country and item for market information analysis of small and medium export sellers. A prediction model was developed using Lasso, XGBoost, and MLP models based on supervised learning and deep learning, and export trends for clothing, cosmetics, and household electronic devices were predicted for Korea's major export countries, the United States, China, and Vietnam. As a result of the prediction, the performance of MAE and RMSE for the Lasso model was excellent, and based on the development results, a market analysis system for small and medium sellers was developed.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(5)
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• pp.147-150
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• 2000

Manual and predictive defrosting method is used in current refrigerators, which have several problems in terms of energy consumption and efficiency. fuming the defrosting system on by the amount of frost remains to be an important problem which has to be improved by refrigerator manufacturers. The sensing of the amount of frost by FDS(Frost Detecting Sensor) and its proper mounting point are investigated in the paper. Also the realization of actual defrosting system through experiments of operation, energy consumption and sensing mechanism is presented.

• 산업공학
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• 제20권1호
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• pp.1-10
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• 2007

The main purpose of this research is to find out whether curriculums of industrial engineering (IE) departments meet the demand of IE graduates working in various fields. The research was conducted as an online questionnaire survey selecting IE Graduates working in industries as practising engineers. 1,324 participants were validated among 1,477 participants. 13 fields were selected and used in the survey. Those were; 1) Mathematical statistics, 2) Computer, 3) Purchase, 4) Production system, 5) Logistics, 6) Marketing, 7) Monetary, 8) Experiment methods, 9) Operations Research (OR), 10) Human Factors, 11) Quality, 12) Engineering management, and 13) Information systems. Using the 5-scale Likert rating, each education subject was assessed both in terms of its usefulness in practices and the amount it being taught in school. As a result, courses such as motion/time study, linear programming that IE has traditionally focused showed less usefulness in practices while it is taught in relatively large amount in schools. However, courses such as 6 sigma, CRM which are closely related to industrial practices showed high usefulness in practices compared with low degree of teaching in school. This was the first ever large scalesurvey conducted for IE graduates in Korea. The result of survey displayed many helpful information on current status and future direction of IE education in Korea.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.491-494
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• 1999

Introduction of digital communication network such as Integrated Services Digital Networks(ISDN) and digital storage media have rapidly developed. Due to a large amount of image data, compression is the key techniques in still image and video using digital signal processing for transmitting and storing. Digital image compression provides solutions for various image applications that represent digital image requiring a large amount of data. In this paper, the proposed DWT(Discrete Wavelet Transform) filter bank is consisted of simple architecture, but it is efficiently designed that a user obtain a wanted compression rate as only input parameter. If it is implemented by FPGA chip, the designed encoder operates in 12MHz.

• 보건행정학회지
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• 제23권3호
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• pp.266-280
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• 2013

Background: Information asymmetry between physicians and patients is one of the most unique characteristics of health care. But as consumerism spreads in health care sector, health care consumers are searching comparative information about quality and cost of providers from many information sources. Providing comparative information to health care consumers not only makes consumers choose hospital rationally, but also invigorates the health care market by providers' competition. However there are few studies regarding information searching behavior of health care consumers, then this study is carried out. Methods: The purpose of this study is to understand the information searching behavior of health care consumers based on their characteristics and the types of medical institutions. For this purpose, 313 spinal patients' data of 11 medical institutions (university hospital, spine specialized hospital, clinic) located in Seoul were collected by self-administered surveys. Results: The results of this study are as follows: 1) t-test/analysis of variance analysis showed that according to various characteristics of health care consumers and the types of medical institutions, the level of information searching of each source and the amount of information searching and searching outcomes are statistically different. 2) Regression analysis showed that influence on searching outcomes are statistically different according to the level of information searching of each source and searching content and the amount of information searching has positive effects on searching outcomes. Conclusion: The significance of this study is to provide empirical basis for establishment of health care policy reflecting information needs and preference of health care consumers.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.129-132
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• 2003

Fixed GOP allocation in MPEG-2 cannot cope with scene change and amount of motion, which results in degradation picture quality. By finding suitable N and M and allocating dynamic GOP, the improvement of picture quality can be achieved. In this paper, N and M are determined by scene change detection and estimation of amount of motion using color histogram per each macroblock. The simulation results show that the average PSNR is improved, especially around the shot boundaries.

• 한국인쇄학회지
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• 제24권2호
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• pp.61-68
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• 2006

Rubber rollers in off-set printing process are one of the most important factor, transferring the ink and water to the plate. Each different roughness of roller surface and different rubber compounds could effect to ink transparency and printability. Three different rubber compounds (NBR, EPDM, PU) and each different roughness of roller surface would show us different result of ink transparency and density of actual printing result. There might be a differences from actual printing result not only the amount of transferred ink, but there is also some other point we should check it out. According to the result of this studies, we found that different rubber compounds and their surface roughness directly effect to the rate of ink transfer. It also shows that the amount of transferred ink is not even and stable amount what we expect to get optimum printability. To reach a targeted printability with rollers, firstly it is necessary to choose correct rubber compounds with certain purpose and the roughness of roller surface has to be as smooth as less than $5{\mu}m{\sim}7{\mu}m$.

• 한국컴퓨터정보학회논문지
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• 제17권10호
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• pp.71-77
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• 2012

본 논문에서는 SIP(Session Initiation Protocol) 환경에서의 분산형 컨퍼런스 모델에서 각 컨퍼런스 서버들의 부하를 줄여 확장성을 높일 수 있는 효율적인 SIP 메시지 제어 방식을 제안하였다. 제안된 시스템에서 컨퍼런스 참가자는 자신의 처리 능력 및 네트워크 상황에 맞추어 컨퍼런스 서버로 부터의 이벤트 통지 메시지 발생량을 실시간으로 제어 할 수 있고, 컨퍼런스 서버와의 세션 유지를 위해 필요한 각종 SIP 메시지의 발생량도 능동적으로 제어 할 수 있도록 하였다. 따라서 본 제어 방식을 사용하여 컨퍼런스 서버들이 처리해야 할 SIP 메시지를 크게 줄일 수 있어 대용량 컨퍼런스 시스템으로의 확장이 용이해지며 SIP 환경에서의 전체 네트워크 트래픽도 크게 감소시킬 수 있게 된다. 이를 위하여 본 연구에서는 효율적인 SIP 메시지 제어에 필요한 구성요소들이 추가된 새로운 컨퍼런스 이벤트 패키지 및 컨퍼런스 정보 데이터 모델이 제시되었다. 제안된 시스템의 성능은 실험을 통하여 분석하였다.

• 품질경영학회지
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• 제52권2호
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• pp.377-394
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• 2024

Purpose: To derive the optimal conditions for the Rubber based colloidal suspension manufacturing process, which made using a stirrer, to apply the mixture design method. Methods: We used two process component and one process variable Mixture design to derive the optimal conditions for the process. The response variables were selected for rotational viscometer measures which can represent Rubber based colloidal suspension quality. The input variables were selected as the values of rubber-organic solvent expressed in proportions as process components and stirring amount as a process variable which are controllable factors in the process. Results: Based on the results of the experiment, rubber and organic solvent and the interaction between stirring amount and rubber and the interaction between stirring amount and rubber and organic solvent were significant. Reproducibility of the regression model was confirmed by the observation that the values obtained from the reproducibility experiment fell within the confidence interval. Additionally, the model predictions were found to be in close agreement with the field measurements. Conclusion: In this study, a regression model was developed to predict the viscosity change of colloidal suspensions based on the proportion of rubber based colloidal suspension. The developed regression model can lead to improved product quality.