• 한국생산제조학회지
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• 제23권4호
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• pp.392-397
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• 2014

Recently, there is an increase in the need for precision linear stages with vacuum compatibility in such areas as lithography equipment for wafer or mask manufacturing, mask mastering equipment for optical data storage and electron beam equipment. A simple design, high stiffness and low cost can be achieved by using ball bearings. However, a ball bearing have friction and wear problems just as in ambient air. In order to decrease the friction, a special finish, a diamond-like carbon (DLC) film coating, is applied to the surface of a guide rail by sputtering deposition. This paper presents the result of an experimental investigation on the control performance of a ball bearing-guided linear motion stage under two environmental conditions: in air and vacuum. A comparison between the results with and without the DLC coating was also considered in the experimental investigation.

• 복식문화연구
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• 제27권1호
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• pp.1-10
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• 2019

Firefighters wear Personal Protective Equipment (PPE) for protection from environmental hazards. However, due to the layers of protective functions, the PPE inevitably adds excessive weight, bulkiness, and thermal stress to firefighters. This study investigated the adverse impact of wearing PPE as an occupational stressor on the firefighter's cognitive functioning. Twenty-three firefighters who had been involved in firefighting at least for 1 year were recruited. The overall changing trend in the firefighter's cognitive functioning (short-term memory, long-term memory, and inductive reasoning) was measured by the scores of three standardized cognitive tests at the baseline and the follow-up, after participating in a moderate-intensity physical activity, wearing a full ensemble of the PPE. The study findings evinced the negative impact of the PPE on the firefighter's cognitive functioning, especially in short-term memory and inductive reasoning. No significant influence was found on the firefighter's long-term memory. The results were consistent when the participant's age and BMI were controlled. The outcomes of the present study will not only fill the gap in the literature, but also provide critical justification to stakeholders, including governments, policymakers, academic communities, and industry, for such efforts to improve human factors of the firefighter's PPE by realizing the negative consequences of the added layers and protective functions on their occupational safety. Study limitations and future directions were also discussed.

• 한국산업융합학회 논문집
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• 제25권6_2호
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• pp.979-986
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• 2022

Chemical accidents are increasing day by day as the industry develops. To prevent such chemical accidents, Korea enacted the Chemicals Control Act. Through these laws, systematic management of chemical substances began. There are various positions in the companies. hazardous chemical supervisors, equipment and technical human, operators and employees. Chemicals-related education for each position should be provided. As a result of the survey, hazardous chemical supervisors and equipment and technical human liked the overall content of the Chemicals Control Act and the education subject on safety management standards for facilities. Conversely, the operators liked the course on how to wear personal protective equipment. The employees preferred subjects such as classification of chemical substances and prevention of chemical accidents. Currently, various modular textbooks are widely available. Rather than general education, it is necessary to select and provide customized subjects that are preferred and interested according to the position. Then it will be more effective in understanding harzardous chemical substances and in preventing chemical accidents.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.313-316
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• 2015

Construction is one of the most dangerous job sectors, which reports tens of thousands of time-loss injuries and deaths every year. These disasters incur delays and additional costs to the projects. The safety management needs to be on the top primary tasks throughout the construction to avoid fatal accidents and to foster safe working environments. One of the safety regulations that are frequently violated is the wearing of personal protection equipment (PPE). In order to facilitate monitoring of the compliance of the PPE wearing regulations, this paper proposes a vision based method that automatically identifies whether workers wear hard hats and safety vests. The method involves three modules - human body detection, identification of safety vest wearing, and hard hat detection. First, human bodies are detected in the video frames captured by real-time on-site construction cameras. The detected human bodies are classified into with/without wearing safety vests based on the color features of their upper parts. Finally, hard hats are detected on the nearby regions of the detected human bodies and the locations of the detected hard hats and human bodies are correlated to reveal their corresponding matches. In this way, the proposed method provides any appearance of the workers without wearing hard hats or safety vests. The method has been tested on onsite videos and the results signify its potential to facilitate site safety monitoring.

• 드라이브 ㆍ 컨트롤
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• 제20권4호
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• pp.45-53
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• 2023

This study optimized the parameters of the helical gear based on the original external meshing helical gear pump, combined with the analysis of the stability and flow of the basic parameters of the equipment; herringbone gears were used to eliminate the axial force generated by the helical gears. An optimized helical gear rotor was built with NX. The error between the simulation and calculation results of pump displacement was 3.95% and the simulation results were valid. Analysis of the outlet pressure and lift changes (maximum change rates of 0.38% and 0.25%), pressure analysis of the XY center plane at different times in the same cycle (no pressure surge or drop), and analysis of the axial force of the primary and driven rotors (axis The axial force is close to 0) were performed. The results showed that the flow pulsation of the external gear pump was slight, the operation was smooth, vibration and friction were reduced, the wear of bearings and other components could be diminished, and the service life of the equipment was extended. The simulation results showed that the external gear pump met the design requirements.

• Journal of Advanced Marine Engineering and Technology
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• 제38권7호
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• pp.854-867
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• 2014

지속적인 유가의 상승에 따라 국제 석유 자본들의 유전개발에 대한 투자가 활발하고 지속적으로 증가하고 있는 추세에 있다. 최근 5년 동안(2008~2013)에 인도된 드릴쉽(drill-ship)은 67척으로 그 이전 30년 동안에 인도된 척수의 두 배에 이른다. 그리고 최근에는 3,000 m 내외의 심해유전 개발이 증가하고 있다. 이에 따라 시추 장비와 시스템이 대형화 추세에 있으며, 이들의 운전을 위한 디젤발전기의 용량이 증가하였다. 디젤발전기 용량은 일반 상선과는 달리 고출력 및 고전압이 요구되며, 이를 충족시키기 위하여 V-type 320 mm 실린더 내경의 고출력 엔진에 대한 수요가 증가하게 되었다. 드릴쉽의 경우 일반 상선 대비 선박건조 기간이 길어짐에 따라 커미셔닝 기간 중 장시간 저 부하 운전이 불가피하여 엔진 윤활유 관리의 중요성이 대두되었다. 최근에는 선박인도 전 크랭크핀에 캠마모(Cam wear)와 같은 이상마모가 발생하였으며 시리즈 호선 및 관련 호선들에 대한 크랭크핀의 전수 검사 결과 정도의 차이가 있었으나 모두 크랭크핀에 이상마모가 발생한 것이 확인되었다. 본 논문은 실제 호선에 적용된 엔진 크랭크핀의 이상마모 발생 원인에 대해 이상마모 메커니즘 분석과 실증결과 분석을 통하여 재발방지를 위한 대책 방안에 대하여 논하였다.

• 사물인터넷융복합논문지
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• 제9권3호
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• pp.75-80
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• 2023

국내 의료취약지에서 공중보건의는 지역민의 일반의료는 물론 응급의료에서 큰 역할을 수행하고 있다. 그러나 공중보건의는 일반적으로 현장 경험이 부족하기 때문에 응급 환자에 대한 대처 능력이 부족하고, 의료장비를 효과적으로 다루지 못하는 것으로 나타났다. 본 연구는 공중보건의에게 필요한 의료장비에 대한 사용법을 스마트 글래스를 이용하여 원격교육으로 진행 후 교육의 효과를 확인하였다. 구체적으로 의료장비 활용 교육을 위해서 스마트 글래스는 리얼웨어를 사용하였으며, 신안군 10개의 섬 지역 공중보건의 10명을 대상으로 하였다. 교육 후 장비 활용 효과와 만족도 모두 3점 이상이었다. 따라서 스마트 글래스를 활용한 원격교육이 의료취약지의 공중보건의를 대상으로 유용하게 활용될 수 있다는 것을 확인하였다.

• 한국멀티미디어학회논문지
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• 제19권5호
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• pp.808-817
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• 2016

Recently, the wearable computing technology with bio-sensors has been rapidly developed and utilized in various areas such as personal health, care-giving for senior citizens who live alone, and sports activities. In particular, the wearable computing equipment to measure vital signs by means of digital yarns and bio sensors is noticeable. The wearable computing devices help users monitor and manage their health in their daily lives through the customized healthcare service. In this paper, we suggest a system for monitoring and analyzing vital signs utilizing smart healthcare clothing with bio-sensors. Vital signs that can be continuously acquired from the clothing is well-known as unstructured data. The amount of data is huge, and they are perceived as the big data. Vital sings are stored by Hadoop Distributed File System(HDFS), and one can build data warehouse for analyzing them in HDFS. We provide health monitoring system based on vital sings that are acquired by biosensors in smart healthcare clothing. We implemented a big data platform which provides health monitoring service to visualize and monitor clinical information and physical activities performed by the users.

• 복식
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• 제58권7호
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• pp.119-132
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• 2008

This study intended to develop and produce a modern form of fashion design for the Korean creative dance performance, 'Crazy Skirt Collage', which expressed conflict between internal ego and a persona in a woman. The qualitative method was used to analyze literature review, internet search and visual data of historically important cases related to the theme. Based on the analysis, the fashion design of the dance performanre by Hwang Hee-Yeon that was actually staged on Towol Theater, one of the Seoul Arts Center, was produced. The results wire as follows; First, the study confirmed a change of persona that revealed a female's animus strongly as it moved into the modern time. Second, the female's persona was expressed through long skirts, slips, dress shoes, handbags, military shoes, dresses with long zippers, trousers, wedding dresses and Korean full skirts during the performance, while the female's animus through male coats, panties, big bags and clock. In conclusion, it is necessary to study new expressive methods, that is, dance clothes using advanced equipment such as lights, videos or other variety of materials. It is also important to understand aesthetics of modern women's ordinary lives and to adapt ordinary clothes to dance clothes in various methods in order to express their modern lives appropriately through Korean creative dance.

• 한국치위생학회지
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• 제17권3호
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• pp.343-354
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• 2017

Objectives: The purpose of this study was to provide a satisfactory and reliable dental care service for the patients and to establish a plan to raise the perception about dental infection control. Methods: The perception of infection control in the dental clinic of the patients was examined who visited to dental clinics, over 20 years old and living in Seoul and Gyeonggi province since December 2016. The questionnaire was used as the survey tool, and 274 questions in the questionnaire were analyzed. Results: Results of examined factors affecting the perception of dental infection control in dental clinics show that the perception of infection control in dental clinics is affected by the degree of university graduates (p<0.05), full-time workers (p<0.01), housewives (p<0.001), and oral health concerns (p<0.05), the perception of infection control of dental medical personnel (p<0.001) in order. Conclusions: Dental medical personnels must thoroughly wash their hands, wear uniforms, wear personal protective equipment, and thoroughly clean and disinfect the interior of a dental clinic.