• 전자통신동향분석
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• 제35권6호
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• pp.137-149
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• 2020

Several multi-agent reinforcement learning (MARL) algorithms have achieved overwhelming results in recent years. They have demonstrated their potential in solving complex problems in the field of real-time strategy online games, robotics, and autonomous vehicles. However these algorithms face many challenges when dealing with massive problem spaces in sparse reward environments. Based on the centralized training and decentralized execution (CTDE) architecture, the MARL algorithms discussed in the literature aim to solve the current challenges by formulating novel concepts of inter-agent modeling, credit assignment, multiagent communication, and the exploration-exploitation dilemma. The fundamental objective of this paper is to deliver a comprehensive survey of existing MARL algorithms based on the problem statements rather than on the technologies. We also discuss several experimental frameworks to provide insight into the use of these algorithms and to motivate some promising directions for future research.

• 대한치과기공학회지
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• 제41권4호
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• pp.337-345
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• 2019

Purpose: The purpose of this study was to enhance curriculum satisfaction of dental laboratory technology and curriculum demands. Methods: From March 5 to March 31, 2019, a self-written questionnaire was conducted for 195 students from the department of dental laboratory technology at a university in Gangwon-do. The analytical methods used were descriptive statistical analysis, frequency analysis, cross analysis, correlation analysis and reliability analysis. The collected data was used for SPSS 18.0 for Windows statistics program. Results: The demand of the school education includes systematic experiments and demand of practical training, acquisition of professional knowledge, introduction of advanced technology curriculum, reduction of national examination-oriented curriculum, and increased professionalism and professionalism as professional professionals. Investigated by the ethics. In addition, they were strongly aware of the necessity of digital education related to CAD / CAM, and there was a high demand for how to operate programs, scanning and design. Conclusion: The curriculum needs to be reorganized to cultivate dental technicians in a changing era, and in-depth centralized curriculum in fields with high practical needs, as well as vocational and ethical views as professionals.

• Smart Structures and Systems
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• 제32권3호
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• pp.179-193
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• 2023

This study explores an alternative to the existing centralized process for data anomaly detection in modern Internet of Things (IoT)-based structural health monitoring (SHM) systems. An edge intelligence framework is proposed for the early detection and classification of various data anomalies facilitating quality enhancement of acquired data before transmitting to a central system. State-of-the-art deep neural network pruning techniques are investigated and compared aiming to significantly reduce the network size so that it can run efficiently on resource-constrained edge devices such as wireless smart sensors. Further, depthwise separable convolution (DSC) is invoked, the integration of which with advanced structural pruning methods exhibited superior compression capability. Last but not least, quantization-aware training (QAT) is adopted for faster processing and lower memory and power consumption. The proposed edge intelligence framework will eventually lead to reduced network overload and latency. This will enable intelligent self-adaptation strategies to be employed to timely deal with a faulty sensor, minimizing the wasteful use of power, memory, and other resources in wireless smart sensors, increasing efficiency, and reducing maintenance costs for modern smart SHM systems. This study presents a theoretical foundation for the proposed framework, the validation of which through actual field trials is a scope for future work.

• 해양환경안전학회지
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• 제20권6호
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• pp.653-662
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• 2014

본 연구에서는 목포해양대학교의 실습선 새누리호를 대상으로 선박의 중앙집중 공조시스템에 공랭식 에어컨을 직접 설치하여 성능을 개선시킨 공기조화시스템으로 운전하였을 경우의 냉방 성능을 비교하고, 선실의 온열환경에 대한 실측조사를 통해서 향후 선박용 공기조화 설계 및 계획에 경험적 기초참고자료로 활용하고자 하는 것이다. 연구결과 동일한 외기조건에서 기존의 중앙집중방식 공조시스템과 개선된 공조시스템으로 운전하였을 경우, 모든 선실의 온도는 $24{\sim}28^{\circ}C$, 습도는 55~75 %로 쾌적한 조건임을 알 수 있었고, 발전기 부하를 측정결과 공기조화시스템의 성능개선에 따라 평균 부하 48 KW, 전부하시 부하율 약 8 %정도 감소하여 1일 연료소모량 FOC는 하루 평균 222[L/day]의 기름이 절약됨을 알 수 있었다. 또한 학생 선실(Cadet No. 21)은 기관실의 전열로 인해서 온도가 높게 나타났는데, 이것은 공기조화 설계 시 취출구 개수 및 전열부하를 고려하지 못한 결과로 판단된다.

• 대순사상논총
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• 제35집
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• pp.427-476
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• 2020

대순진리회는 1969년 박우당에 의해 공식적으로 창설되었다. 이 글은 대순진리회가 증산을 신앙하는 다른 종단과 역사와 사상을 공유하고 있지만 조직 측면에서 타종단과 구별됨을 보여주고자 한다. 대순진리회 조직의 양대 기구인 본부와 방면은 대순진리회가 신종교로서 급속한 성장을 이루는 데 서로 기여했다. 본부는 중앙 집권적인 위계질서가 있는 반면, 방면은 친족 같은 강한 충성도와 공동체의식을 보여준다. 두 조직 기구에 공통적인 특성은 계보(lineage) 개념으로 이는 대순진리회 양대 조직의 분절화 원리이다. 미세하게 균형 잡힌 두 조직기구는 대순진리회의 종교적 사명 실현에 크게 기여했다. 균형의 첫 번째 축은 본부이다. 본부는 여주와 여주 외 지역 도장 및 수련센터의 핵심 종단 기구를 포함한다. 이러한 기구들은 모두 박우당 도전에 의해 설립되었다. 박우당 도전은 종단 운영의 제반사항을 총괄하는 종단의 헌법 곧 도헌을 제정하였다. 중앙종의회로부터 포덕, 감사, 기획 등에 이르는 본부의 제반 운영은 박우당 도전의 운영지침에 충실히 부합한다. 균형의 두 번째 축은 방면이다. 비교적 대규모 방면들은 그 자체가 복합적인 조직이다. 이 연구의 결론은 본부와 방면이라는 양대 축에 대한 조직유형적 특성구분이다. 로버트 퀸과 킴 카메론의 분류에 따른다면 대순진리회의 본부는 효율성을 중시하는 전형적인 중앙집권화 조직이다. 이에 반해 방면은 집단정체성과 공동체의식을 중시하는 친족에 가까운 조직이다.

• 복식
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• 제34권
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• pp.109-120
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• 1997

The conservation of collections in muse-ums is an important aspect for our her-itage. The control of museum environment is a vital factor in the preservation of cool-lections. Inappropriate or fluctuating envi-ronmental conditions can cause irreparable damage to works of arts. In this research we investigated the ac-tual conditions of museum environment for old testiles using questionnaire and mea-sured dye fasing of old textiles on exhibi-tion for 2 months in a university museum the major results are as follows: 1. The control of temperature and rela-tive humidity is a vital factors I the preservation of old textiles in museum generally acceptable temperature and rel-ative humidity standards for old textiles are 18-23$^{\circ}C$ and 50-65% R. H and light level for textiles on exhibition should be limited to 30-50 lux. 2, In university museums the limate control system in exhibition and storage area is in an early stage. Therefore to minimize the deterioration of old textiles the best method of controlling the envi-ronment is to have centralized climate control system in sorage area as well as in display area. 3. Conservator is needed to maintain collections scientifically. Only professional conservator by combining scientific tech-nical and artistic training has the exper-tise needed to maintain the physical in-tegrity of old textiles. In order to solve the inferior environment of museums the staff should recognize the importance of the condition of exhibition and storage. 4. Old textiles are susceptible to damage by light and associated heat. Dyed textiles which have been exhibited under the light without any UV filter were faded notice-ably within two months of exhibition. Light levels for textiles on exhibition should be limited to 30-50 lux. It is de-sirable to use special light source that can absorb UV. and UV filter is also recom-mended to reduce photodegradation of old textiles.

• 대한영양사협회학술지
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• 제6권2호
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• pp.136-147
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• 2000

The aim of this research was to examine the management practices related to foodservice.clinical nutrition service provided by hospital foodservice operations. A survey of 30 hospital food nutrition service departments was undertaken and detailed information was collected from each, including surveys of 176 dietitians and 30 foodservice managers. Statistical data analysis was completed using the SAS/win 6.11 package for descriptive analysis and t-test. The results of this study can be summarized as follows : Out of 30 hospitals, 73.3%(22) were directly operated and 26.7%(8) were under contract foodservice management. Licensed number of beds were 768.7, with an average length of 11.4 days. The general characteristics of the dietitians were that 49.4% were aged between 25-29, and 60.8% were ordinary dietitians. 76.7% had bachelor's degree, 15.9% with master's degree and 7.4% were college graduates. Most hospital dietitians had internship training and 35.2% took a training course of 6 to 12 months. The average space of kitchen was 452.52 $m^2$, with 133.63$m^2$ for modified diet space and 18.13$m^2$ for nutrition counselling room space. The total number of normal meals was 1,255.47, with 502.93 of modified meals. The average calorie of normal meals was 2,145.04kcal, with 91.9g of protein contained in normal meal. The total food waste was 351.40kg. An average monthly cost for disposing food waste was 745,171.67 won. 83.3% of the kitchens were on the 1st basement and only 66.7%(20) of 30 hospitals had its own nutrition counselling room. 80% used dishwashers and 66.7% had an exclusive elevator for delivering meals. 80.0% of hospitals used centralized delivery service. 90% had established an area for hygiene division, 70% used dry zone within the dishwashers for sterilization, 66.7% provided spoon and chopstick, and 100% used dish cover. As means of food waste treatment, most hospitals(56.7%) used animal feed by contracters, followed by means of collection by contracters(30%) and in-house high speed fermentation machines(13.3%). It was found that only 33.3% hospitals regularly checked temperatures of the meals given to patients. Total productivity index was 3.72(meals/hour) in average, with an average productivity index for normal diet of 5.41. Average productivity index for modified diet was 4.62. Productivity indices for patient meals and clinical nutrition were 5.01(meals/hour) and 1.12(cases/hour) respectively and hospitals under self-operated foodservice management received higher points on clinical nutrition productivity index(P<0.01) than hospitals under contract foodservice management.

• 한국식품위생안전성학회지
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• 제12권3호
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• pp.240-253
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• 1997

The main problems contributing to food poisoning outbreaks in institutional settings and a home were reviewed and analyzed through the epidemiological investigations of food poisoning. The major documented factors included improper holding temperatures, inadequate cooking, poor personal hygiene, cross-contamination and contaminated equipment, food from unsafe sources, failure to follow food hygiene policies, and lack of education, training, monitoring and superivision. Usually more than one factor contributed to the development of an outbreak. (1) Use of improper holding temperatures was the single most important factor contributing to food poisoning. They included improper cooling, allowing a laps of time (12 hours or more) between preparing food and eating it, improper hot holding, and inadequate or improper thawing. Food thermometers were not used in most of the instances. (2) In inadequate cooking, the core temperature of food during and after cooking had not been measured, and routine monitoring was limited to recording the temperature of plated meals. Compared with conventional methods of cooking, microwave ovens did not protect against food poisoning as effectively. Centralized food preparation potentially increased the risk of food poisoning outbreaks. (3) Poor personal hygiene both at the individual level (improper handwashing and lack of proper hygienic practices) and at the institutional level (poor general sanitization) increased the risk of transmission. Person to person transmission of enteric pathogens through direct contact and via fomites has been noted in several instances. (4) Obtaining food from unsafe sources was a risk factor in outbreaks of food poisoning. Food risks were high when food was grown or harvested from contaminated areas. Possibilities included contamination in the field, in transport, at the retail site, or at the time it was prepared for serving. (5) Cross-contamination and inadequate cleaning/handling of equipment became potential vehicles of food poisoning. Failure to separate cooked food from raw food was also a risk factor. (6) Failure to follow food hygiene policies also provided opportunities for outbreaks of food poisoning. It included improper hygienic practices during food preparation, neglect of personnel policies (involvement of symptomatic workers in food preparation), poor results on routine inspections, and disregarding the results and recommendations of an inspection. (7) Lack of formal and in-service education, training, monitoring, and supervision of food handlers or supervisors were critical and perhaps neglected elements in occurrences of food poisoning.

• 한국정보시스템학회지:정보시스템연구
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• 제18권2호
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• pp.83-109
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• 2009

Such factors as the increase of population and me development of information technology were raised the needs of citizens in Korea. To meet these needs for the better services, Korean government has built up the computer networks that connect forty-two administrative operations of the central government since 1984. Through the computerization of administrative services, Korean government has been pursuing the balanced development among the regions in the country. To this end, regional informationization has been implemented since the mid 1980s. Specifically, rural villages has become information network villages (invils) by adopting computers and networks. Consequently, three hundred thirty-seven invils were implemented in the country. By selecting forty-six invils in Kyeongbuk province in Korea, this research was intended to find efficient and effective ways of operating invils. To find the problems and opportunities of the invils, the researcher has visited each of the forty-six invils between January 12th. and February 12th. in 2009. Two-round surveys were distributed to the managers of these forty-six invils. This research identified ten problems as below. a. Problems after the implementation of invils b. Problems occurred at the same rime as the operation of invils c. Problems with regard to the invil managers d. Problems with regard to the criteria of success or failure e. Problems with regard to the cooperation of administrative offices f. Problems with regard to the boosting of invil experience g. Problems with regard to software assurance developed in invils h. Problems with regard to incentives to invlis i. Problems with regard to the role of invils To solve these problems in hands of invils, this research suggested policy ideas in two levels: 1. invils 2. government Policies should be implemented by invils: a. The strengthening of training rural people for the better utilization of computers b. The strengthening of the regulations on membership management and electronic commerce c. The establishment of the invil managers' job tenure d. The reformation of measuring the success or failure of an invil e. The integration of administrative offices centralized by invils f. The establishment of trust between administrative offices and invils g. the integration of experience villages and invil managing offices h. The revitalization of incentives to invils and experience villages i. The enforcement of cooperative offices among invils Policies to be implemented by the government: a. The revitalization of electronic commerce through invils b. The rationalization of selecting invils in an area c. The unification of various offices for rural informationization d. The construction of portal sites for rural areas e. The continuous training of IT leaders in rural areas f. The provision of pays to invil managers based on break-even points g. The transcendentalization toward the second new town movement

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.1243-1244
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• 2022

In recent years, the growing interest in off-site construction has led to factories scaling up their manufacturing and production processes in the construction sector. Consequently, continuous large-scale site monitoring in low-variability environments, such as prefabricated components production plants (precast concrete production), has gained increasing importance. Although many studies on computer vision-based site monitoring have been conducted, challenges for deploying this technology for large-scale field applications still remain. One of the issues is collecting and transmitting vast amounts of video data. Continuous site monitoring systems are based on real-time video data collection and analysis, which requires excessive computational resources and network traffic. In addition, it is difficult to integrate various object information with different sizes and scales into a single scene. Various sizes and types of objects (e.g., workers, heavy equipment, and materials) exist in a plant production environment, and these objects should be detected simultaneously for effective site monitoring. However, with the existing object detection algorithms, it is difficult to simultaneously detect objects with significant differences in size because collecting and training massive amounts of object image data with various scales is necessary. This study thus developed a large-scale site monitoring system using edge computing and a small-object detection system to solve these problems. Edge computing is a distributed information technology architecture wherein the image or video data is processed near the originating source, not on a centralized server or cloud. By inferring information from the AI computing module equipped with CCTVs and communicating only the processed information with the server, it is possible to reduce excessive network traffic. Small-object detection is an innovative method to detect different-sized objects by cropping the raw image and setting the appropriate number of rows and columns for image splitting based on the target object size. This enables the detection of small objects from cropped and magnified images. The detected small objects can then be expressed in the original image. In the inference process, this study used the YOLO-v5 algorithm, known for its fast processing speed and widely used for real-time object detection. This method could effectively detect large and even small objects that were difficult to detect with the existing object detection algorithms. When the large-scale site monitoring system was tested, it performed well in detecting small objects, such as workers in a large-scale view of construction sites, which were inaccurately detected by the existing algorithms. Our next goal is to incorporate various safety monitoring and risk analysis algorithms into this system, such as collision risk estimation, based on the time-to-collision concept, enabling the optimization of safety routes by accumulating workers' paths and inferring the risky areas based on workers' trajectory patterns. Through such developments, this continuous large-scale site monitoring system can guide a construction plant's safety management system more effectively.