• Journal of KSNVE
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• 제9권1호
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• pp.184-188
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• 1999

Noise regulation of heavy construction machinery is getting stricter： 3 dB per every 4 year in European community. To meet this requirement many engineers have adopted the enclosing structures with thick absorbing materials and small opening, This increases internal temperature of the enclosure which have engine systems such as electric equipment that are vulnerable to heat, and engine block and muffler that can be regarded as heat sources. So noise control engineers have to consider a coupling problem: combining heat balance and noise reduction. This paper describes this approach by introducing simple heat transfer theory and SEA. The enclosing system of the loader whose enclosing structure consists of two rooms is investigated to show the validity of this method. The results represent that the simple heat transfer theory can be useful to estimate cooling performance when it is linked together by the back pressure theory in duct system. and the radiated noise can also be estimated by the SEA. Therefore a designer can use these approaches to define the opening ratio of an enclosure and the mass flow rate of air considering radiating noise.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 한국주거학회 2008년도 춘계학술발표대회 논문집
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• pp.354-359
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• 2008

The purpose of this study is to find out the changes on the metropolitan apartment unit plans based on the interior spaces for women such as master bedroom, bathroom and attached spaces to the master bedroom, living room, diningroom, kitchen, utility room, and balcony. This study used the content analysis method, space syntax. Contents were the floor plans with 3 rooms type and limited to about $105m^2$ among drawings of an apartment encyclopedia. Above all, 174 unit plans were analyzed until now. Specifically, using $S^3$-Convex program, the integration and control value periodically of the interior spaces for women(master bedroom, bathroom and attached spaces to the master bedroom, living room, diningroom, kitchen, utility room) is understood. Second, using SPSS package 16.0, relative size of the interior spaces for women on the unit floor plan is understood periodically. Finally, the changes on the apartment unit plans based on a woman' aspect after 1980's is reanalyzed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• 제24권11호
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• pp.813-822
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• 2012

In this study, the multizone simulation for biosafety of BSL3 lab. and energy simulation are carried out simultaneously by using linked model of CONTAM and TRNSYS. In BSL3 lab., annual energy consumption is approximately five to ten times more than the magnitude of the office building. This is because required air change rate is extremely large and it is difficult to maintain room pressure difference efficiently. To maintain pressure difference between laboratory rooms through sealing condition of doors and proper airflow control is significant. In this study, to predict indoor environment of the BSL3 lab.(Influenza A research lab.), the multizone simulation for four kinds of biohazard scenario is also performed as part of risk assessment. Multizone and energy simulation results by using linked model show that these approaches are used as a tool for the energy efficient design and operation method for the safer BSL3 lab. facilities.

• Journal of Environmental Health Sciences
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• 제28권1호
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• pp.11-20
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• 2002

Tobacco smoke was confirmed as a human carcinogen by many research results. Because many adolescents stay long time in the PC game room, they are exposed to much of tobacco smoke. To evaluate the effect of passive smoking in the PC game room, airborne nicotine concentrations in 2 PC game rooms in Sung-nam city and urinary cotinine concentrations were measured for 20 adolescents. And the subjects were interviewed for duration and time in PC game room and smoking pattern. Subjects are composed of each of 10 smokers(5 males and 5 females) and 10 nonsmokers(5 males and 5 females). They stayed for three hours in the PC game room without smoking. Concentrations of nicotine in smokers and nonsmokers were 129.72 $\mu$g/$^3$ and 99.99 $\mu$g/m$^3$, respectively. Urinary cotinine concentrations were increased as time goes on after exposure to nicotine and showed maximum value at 9.45 hours after nicotine exposure and were 32.21 and 110.66 $\mu$g/L for nonsmoker and smokers. The more using time and frequency in PC game room, the higher urinary cotinine maximum concentration and the longer using duration, also the more increase urinary cotinine concentration. Urinary cotinine has a tendency to increase by passive smoking. Therefore, it is recommended that the effective control for indoor air quality and extensive research be needed to reduce nicotine concentration by passive smoking in the PC game room.

• Journal of Korean Home Economics Education Association
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• 제8권1호
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• pp.11-21
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• 1996

The purpose of this study was to investigate the knowledge on nutrition, meal management and dietary intake of self-boarding highschool students. Total of 354 self-boarding students living in Ku-mi and Kim-chon, 182 males and 172 females, who cooks foods for oneself participated in this study. The data were collected through questionnaires and the results were summarized as follows： 1. Most subjects had adapted the lifestyle of self-boarding from the 1st grade of highschool, and half of them lived alone. About two-thirds of subjects visited their home once a week or more, and most of their boarding rooms were located at near the highschool they attended. 2. Their nutrition knowledge score was rather high with average 13.95 point out of possible 20. Female students got more points than male students. 3. In meal management, foods purchasing and sanitary control were managed quite well but meal planning and cooking were not managed well enough. In general, meal management score of female students were higher than those of male students. 4. About the dietary intake, female students took more various foods than male students as judged by foods intake frequency score. Two-thirds of subjects often skipped meals and only half of them always took boxed lunch. Also they depended too much upon processed and instant foods. 5. Meal management score showed significantly positive correlations with nutrition knowledge score and with foods intake frequency score. But the correlation between nutrition knowledge score and foods intake frequency score was not significant.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.683-686
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• 2000

The chargers for DC power supply of the contro1lers, which have been installed in the relay rooms in 345/154kV substations of KEPCO, lag in both aspects of technique and performance. Moreover, as they are SCR-based, they dont meet the performance requirements of todays digital and automated controllers. Now two controllers are running in pair and one of those is for reservation. There are lots of troubles because the patrol engineering team has to replace them manually whenever they are out of order. So it is expected to bring convenience if the charger replacement is automated. Also, the existing chargers take much space, weight and cost - which have increased the need of development to make them smaller, less expensive, and have high quality. We will develop a charger system which has one fifth of the weight of the existing system by double-integrating the volume. The new system will be ready for a future full unmanned system with integrated pores for remote control, state-of-the-art digital features, and more than 90% efficiency/power factor against 80% efficiency/power factor of the existing system.

• Parasites, Hosts and Diseases
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• 제49권3호
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• pp.299-302
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• 2011

During experimental Eimeria infections in chickens, facilities are often contaminated by fecal oocysts known to be highly resistant to both chemical and enzymatic treatments. Thus, studies using experimental Eimeria infections have been limited due to the difficulty of complete elimination of residual oocysts from both cages and facilities. To overcome this limitation, simple, inexpensive, and disposable cages were constructed from cardboard boxes and tested during experimental Eimeria maxima infections. The cages were used in animal rooms with only a 1.7% evidence of coccidia contamination between adjacent cages. No significant differences in fecal oocyst output and body weight gain were noted between animals housed in disposable cages and animals housed in wire control cages. This cage design is a useful means for preventing oocyst contamination during experimental conditions, suggesting that this disposable cage design could be used for other avian infectious disease studies.

• Journal of The Korea Institute of Healthcare Architecture
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• 제25권2호
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• pp.27-35
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• 2019

Purpose: This study is to address the spacial composition of a standard ward and bedroom size for sake of infection control and efficient medical service. Methods: Spacial composition of a standard ward has been proposed by comparative analysis of 5 big hospitals' wards. Bedroom sizes have been explored on the ground of Health care facility regulations from Korea, USA, Australia and Canada. Of course, Literature and field survey have been conducted in order to draw out various bedroom sizes. Results: 16 basic and some other additional spaces have been proposed for the composition of hospital standard ward. Area of Single bedroom is $11.6m^2$, and that of multi-beded room is $7.4m^2$. Bed to bed Clearance is 1.5m, spacing between bedsize and hard wall is 0.9m in 1~2 beded room, 0.75m in 4-beded room. Space clearance between Foot side of bed and curtain is proposed as 0.3m and additional 0.9m is necessary for the circulation. Implications: The result of this study can be applied to the new cons.

• Journal of Drive and Control
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• 제19권1호
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• pp.62-68
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• 2022

Considering the characteristics of industrial machines that lack vehicle-induced wind, forced convection by a cooling fan is mostly required. Therefore, numerical analysis of an engine room is usually performed to examine the cooling performance in the room. However, most engine rooms consist of a number of parts and components at specific positions, leading to high costs for numerical modeling and simulation. In this paper, a new methodology for three-dimensional computer-assisted design simplification was proposed, especially for the pile of components and parts at the engine room outlet. A porous media model and regression analysis were used to derive a meta-model for imitating the flow rate reduction at the outlet by the pile. The results showed that the fitted model was reasonable considering the coefficient of determination. The final numerical model of the engine room was then used to simulate the velocity distribution by changing the mass flow rate at the outlet. The results showed that both velocity distributions were significantly changed in each case and the meta-model was valid in imitating the flow rate reduction by some piles of components and parts.

• The Journal of Korea Robotics Society
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• 제19권2호
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• pp.149-158
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• 2024

This paper presents a robust autonomous navigation and reconnaissance system for tracked robots, designed to handle complex multi-floor indoor environments with stairs. We introduce a localization algorithm that adjusts scan matching parameters to robustly estimate positions and create maps in environments with scarce features, such as narrow rooms and staircases. Our system also features a path planning algorithm that calculates distance costs from surrounding obstacles, integrated with a specialized PID controller tuned to the robot's differential kinematics for collision-free navigation in confined spaces. The perception module leverages multi-image fusion and camera-LiDAR fusion to accurately detect and map the 3D positions of objects around the robot in real time. Through practical tests in real settings, we have verified that our system performs reliably. Based on this reliability, we expect that our research team's autonomous reconnaissance system will be practically utilized in actual disaster situations and environments that are difficult for humans to access, thereby making a significant contribution.