• Journal of the Korean Institute of Landscape Architecture
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• v.21 no.3
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• pp.51-64
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• 1993

Meeting the rapidly increasing demand for natural outdoor recreation, Korea Forestry Administration established 26 places of $\ulcorner$Natural Recreation Forest$\lrcorner$ zones. By 2000 year, 100 zones were planned to cover the entire country. But there was no accurate information about demand of $\ulcorner$Natural Recreation Forest$\lrcorner$. Therefore, this study was carried out to forecast the quantitive demand of $\ulcorner$Natural Recreation Forest$\lrcorner$. To forecast the 'demand of 2001 year, forecasting unit was determined to $\ulcorner$Visitor. Day$\lrcorner$, and three quantifing methods were applied. The results of demand by each forecating method were as follows: 1) Questionnaire survey method for willingness to participate was 16,651,000(visitor. day). 2) application of similiar situation threshold method was 14,540,000(visitor. day). 3) Demand partition method by secondary data was 10,775,000(visitor, day). Comprised of these results. The scope estimate of $\ulcorner$Natural Recreation Forest$\lrcorner$ demand was proposed as 8,110,000(Minimum) - 27,088,000(Miximum). The point estimate of demand which were proposed as strategic guidelines was 16,651,000(visitor. day). These results implied that recently announced 111 predetermined $\ulcorner$Natural Recreation Forest$\lrcorner$ zones supposed to be overcrowded meeting the forcasted demand level of 2001 year.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.862-865
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• 2004

The system air conditioner has an outdoor unit and a number of indoor units, which connected by several long pipes. In comparison with building HAVC system, the system air conditioner doesn't need lots of facilities, such as control of room, cooling tower, etc. At the beginning stage for the market of the system air conditioner, its main application was a school which size is small to use the building HAVC and large to use home air conditioning system, such as PAC (package air conditioner), RAC (room air conditioner). Therefore, because of the advantages of the system air conditioner mentioned above, the market is expanded rapidly. Since it is difficult to evaluate the noise caused by the system air conditioner because it has to be implemented before the finish of construction, the prediction or estimation of the noise by using CAE technology should be very important. In this research, using a commercial code, RAYNOISE, the noise is estimated to improve the design of building.

• Journal of Fashion Business
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• v.22 no.6
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• pp.94-104
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• 2018

The objective of this study was to develop a wearable systems that protect users, based on sensors that are easy to use, from accidents caused by harmful gases in the operator's poor working environment or the risk of ultraviolet rays during outdoor activities. By developing smart wappen with Light Emitting Diode (LED) light alarm function including UV sensor and gas sensor and central processing unit, systems that are applied to daily wear and work clothes to explore the possibility of user-centered, harmful environment monitoring products in real time were proposed. Each sensor was applied to sportswear and work clothes and the wappen system consisted of lightweight and thin form as a whole. Wappen to cover the device had one sheet cover on the front and another cover from the inside to form a sandwich like formation. Wappen was made in the same form as regular clothes that doesn't damage the exterior then a removable wappen system was developed using Velcro and snap methods to enable the separation of device or the exchange of batteries. De-adhesion method can occur in two ways, from the outside and from the inside, so the design is selected depending on the application. This study shows the significance of the development of sensor-based smart clothing, in that it presented a universal model for users.

• Journal of the Semiconductor & Display Technology
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• v.22 no.2
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• pp.112-119
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• 2023

In urban environments, signals of Global Positioning System (GPS) can be blocked and reflected by tall buildings, large vehicles, and complex components of road network. Therefore, the performance of the positioning system using the GPS module in urban areas can be degraded due to the loss of GPS signals necessary for the position estimation. To deal with this issue, various localization schemes using inertial measurement unit (IMU) sensors, such as gyroscope and accelerometer, and Bayesian filters, such as Kalman filter (KF) and particle filter (PF), have been designed to enhance the performance of the GPS-based positioning system. Among Bayesian filters, the PF has been widely used for the target tracking and vehicle navigation, since it can provide superior performance in estimating the state of a dynamic system under nonlinear/non-Gaussian circumstance. This paper presents a positioning system that uses the double-stacked particle filter (DSPF) as well as the accelerometer, gyroscope, and GPS receiver on the smartphone to provide higher pedestrian positioning accuracy in urban environments. The DSPF employs a nonparametric technique (Parzen-window) to create the multimodal target distribution that approximates the posterior distribution. Experimental results show that the DSPF-based positioning system can provide the significant improvement of the pedestrian position estimation in urban environments.

• Journal of KIISE:Software and Applications
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• v.33 no.1
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• pp.69-83
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• 2006

This paper describes an image disparity estimation method using a segmented-region based stereo matching. Segmented-region based disparity estimation yields a disparity map as the unit of segmented region. However, there is a problem that it estimates disparity imprecisely. The reason is that because it not only have matching errors but also apply an identical way to disparity estimation, which is not considered each type of matched regions. To solve this problem, we proposes a disparity estimation method which is considered the type of matched regions. That is, the proposed method classifies whole matched regions into similar-matched region, dissimilar-matched region, false-matched region and miss-matched region by analyzing the type of matched regions. We then performs proper disparity estimation for each type of matched regions. This method minimizes the error in estimating disparity which is caused by inaccurate matching and also improves the accuracy of disparity of the well-matched regions. For the purpose of performance evaluations, we perform tests on a variety of scenes for synthetic, indoor and outdoor images. As a result of tests, we can obtain a dense disparity map which has the improved accuracy. The remarkable result is that the accuracy of disparity is also improved considerably for complex outdoor images which are barely treatable in the previous methods.

• Journal of Energy Engineering
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• v.22 no.2
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• pp.211-225
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• 2013

To run an optimal operation of Integrated energy supply facilities, we need to analyze heat consumption patterns of District heating users and derive optimum and maximum load ratio of heat production facilities unit. This study selects three District heat production facilities. It also classifies District heating users into residential apartment buildings and eight non-residential buildings and analyzes heat consumption results for an year. Finally it carries out the analysis of how the ratio change of each type affects maximum load ratio, facility utilization ratio, heat supply range. According to this study, three different District heat facilities of residential apartment building show similar daily and annual heat consumption patterns. Annual average load ratio, maximum load ratio and annual heat demand increase as outdoor temperatures decrease. Non-residential buildings in urban District focused on apartment buildings display similar by the daily and annual heat consumption patterns. Yet their daily and annual maximum load ratio differ according to outdoor temperature, District, building types and their composition ratio. In the case of urban District focused on apartment buildings reach optimum and maximum load ratio when apartment buildings reaches 60-70% of the total. At that point heat supply range becomes maximized and the most economic efficiency is obtained.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3389-3395
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• 2014

Conventional methods, such as the clock time control method and temperature difference control method, for defrost control often encounter mal-defrost and a waste of energy. Therefore, a more efficient method is needed to control defrosting precisely. A photoelectric sensor unit consisting of an emitter and a collector was installed in the front of outdoor heat exchanger. Accurate defrost control was performed by monitoring and using the change in output voltage according to the presence of frost. In this study, experiments were performed to determine if the performance and characteristic curves obtained using the clock time control method can be reproduced using a photoelectric sensor under the heating and defrosting capacity test condition described at KS C 9306. The output voltage of the phototransistor (receiver) and heating capacity, power consumption, and surface temperature of the outdoor heat exchanger, were compared. The results showed that photoelectric sensors can be used as a defrost control method. On-off control timing of the clock time defrosting method was in good agreement with those predicted by the output voltage of the photoelectric sensor.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.3
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• pp.84-93
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• 2010

Compaction of backfill material of Underground power lines is difficult, especially under pipeline. so it could cause structural problem because of low compaction efficiency. So various methods have been taken to solve the problem and one of them is CLSM(Controled low-strength material accelerated flow ability). But In other countries, these are already in progress for a long time to research and development and recently on practical steps. But, in our country, study for only general structures, not for underground power line structure that is being constructed at night rapidly. In this study, we performed property tests and indoor & outdoor test (3 cases). The tests showed flow ability reached at the limit construction(160 mm) flowability by 9 to 15 minute after starting to mix, and construction buoyant is lowering after placing CLSM by 70 % of theoretical buoyant that is calculated by unit weight of material. In this paper, we performed indoor tests and outdoor tests to estimate mechanical properties and to suggest construction method(using batch plant, setting spacer at 1.8 m and placing at 2m) for CLSM that using surplus soil. And the test showed good results for construction quality, workability and structure safety.

• Korean Journal of Construction Engineering and Management
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• v.11 no.3
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• pp.13-22
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• 2010

From now on, the aged apartment or house is expected to increase rapidly. So, we have to build a process of remodeling and develop the new technique. Demolition work is needed for systematic plan and management. However, contractors of the remodeling project established a rough plan and did not consider recycling wastes, safety of workers and structural stability of building. Therefore, we need a step to develop a assessment system, verify and make specified. This paper evaluated how much improve on construction speed, work efficiency, intensity of work and influence with another process comparing the existing method with the new demolition method. The qualitative and quantitative assessment system are developed with these output. The case study was carried out experimental group and control group, based on developed assessment system, which have the same condition. The existing method was made up of 3 steps- 1)Demolish windows, doors and iron goods, 2)Demolish indoor and outdoor walls, 3)Drop the waste. The new demolition method was made up of 5 steps- 1)Demolish windows, doors and iron goods, 2)Demolish the ceiling and wall's finishing materials, 3)Demolish the floor's finishing materials, 4)Demolish indoor and outdoor walls, 5)Drop the waste. Work time, idle time, the character of a work unit are analyzed by mock-up test. This study's output is expected to establish a systematic process of new demolition method and based on the maximizing waste recycling work in our construction industry.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.2
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• pp.202-210
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• 2015

Objectives: The purpose of this study was to examine clean room(C/R) structure, air conditioning and contamination control systems and to provide basic information for identifying a correlation between the semiconductor work environment and workers' disease. Methods: This study was conducted at 200 mm and 300 mm semiconductor wafer fabrication facilities. The C/R structure and air conditioning method were investigated using basic engineering data from documentation for C/R construction. Furthermore, contamination parameters such as airborne particles, temperature, humidity, acids, ammonia, organic compounds, and vibration in the C/R were based on the International Technology Roadmap for Semiconductors(ITRS). The properties of contamination control systems and the current status of monitoring of various contaminants in the C/R were investigated. Results: 200 mm and 300 mm wafer fabrication facilities were divided into fab(C/R) and sub fab(Plenum), and fab, clean sub fab and facility sub fab, respectively. Fresh air(FA) is supplied in the plenum or clean sub fab by the outdoor air handling unit system which purifies outdoor air. FA supply or contaminated indoor air ventilation rates in the 200 mm and 300 mm wafer fabrication facilities are approximately 10-25%. Furthermore, semiconductor clean rooms strictly controlled airborne particles(${\leq}1,000{\sharp}/ft^3$), temperature($23{\pm}0.5^{\circ}C$), humidity($45{\pm}5%$), air velocity(0.4 m/s), air change(60-80 cycles/hr), vibration(${\leq}1cm/s^2$), and differential pressure(atmospheric pressure$+1.0-2.5mmH_2O$) through air handling and contamination control systems. In addition, acids, alkali and ozone are managed at less than internal criteria by chemical filters. Conclusions: Semiconductor clean rooms can be a pleasant environment for workers as well as semiconductor devices. However, based on the precautionary principle, it may be necessary to continuously improve semiconductor processes and the work environment.