• Title/Summary/Keyword: Ceiling unit

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Acceptable Supply Air Conditions of Dedicated Outdoor Air System for a High-rise Apartment Building (초고층 공동주택 외기전담 시스템 기반 중앙 공급식 환기시스템의 적정 급기조건 설정)

  • Kim, Min-Hwi;Kim, Jin-Hyo;Kwon, Oh-Hyun;Jeong, Jae-Weon
    • 한국태양에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.285-290
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    • 2009
  • The main thrust of this paper is to investigate acceptable supply air conditions of a dedicated outdoor air system (DOAS) for highrise apartment buildings. As for a typical $132-m^2$ apartment unit, it was assumed that centralized DOAS-Ceiling Radiant Cooling Panel was installed. Transient behavior and control characteristics of each system were modeled numerically using a commercial equation solver program. The optimized dew point temperature of the DOAS was discussed on the basis of the ASHRAE standard 62.1-2007 and the current Korean ventilation standard for apartments. It was found that the optimized dew point temperature of the DOAS supply air accommodating total latent load of a space is $11-12^{\circ}C$ and the appropriate supply air temperature of the DOAS is $11-12^{\circ}C$ in cooling period and neutral temperature of $18-20^{\circ}C$ in intermediate period.

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A Study on the Standard Drawings of Seoul Middle School Architecture in 1975 (1975년 서울시 중학교 표준설계도에 관한 연구)

  • Lee, Jeong-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.5
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    • pp.2497-2504
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    • 2013
  • This study aims to analyze the 'Standard Drawings for School Facilities' issued by Seoul Education Committee in 1975 because it is the early example for middle school architecture. The results of this study are summarized as follows 1) In general trend of single-corridor type block plan, there are also changes in floor plan like no-corridor type block plan, $9.9{\times}6.6m$ classroom unit for the better daylight condition, built-in storage for students. 2) As for elevation design, it is characterized as daylight-oriented, functional exterior for without making full use of design elements. 3) Standardized dimensions are used as a rule in the height of story, ceiling, window sill and etc. Transitional characteristics of the early RC school architecture are found in exposed ceiling, incomplete insulation structure and mixed use of wood framed floor of earlier type. 4) Contrast to main school building, gymnasium shows the intend to express the symbolism of school architecture with diverse elevation design elements and the plasticity of building mass. 5) Separated plan of toilet and night-duty building also show the transitional characteristics. As conclusion, though showing the stereotyped school architecture, on the other hand, 'Standard Drawings for School Facilities' (1975) makes it possible to see the way of coping with the demands for school architecture in that time and the transition of school architecture. This is the main value of it as the material for the studies related to the history of educational facilities.

The study on enhanced micro climate of the oyster mushroom cultivation house with multi-layered shelves by using CFD analysis (CFD 분석에 의한 느타리버섯 재배사 환경균일성 향상 연구)

  • Lee, Sung-Hyoun;Yu, Byeong-Kee;Lee, Chan-Jung;Lim, Yeong-Taek
    • Journal of Mushroom
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    • v.15 no.1
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    • pp.14-20
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    • 2017
  • The oyster mushroom cultivation house typically has multiple layers of growing shelves that cause the disturbance of air circulation inside the mushroom house. Due to this instability in the internal environment, growth distinction occurs according to the area of the growing shelves. It is known that minimal air circulation around the mushroom cap facilitates the metabolism of mushrooms and improves their quality. For the purpose of this study, a CFD analysis FLUENT R16 has been carried out to improve the internal environment uniformity of the oyster mushroom cultivation house. It is found that installing a section of the working passage towards the ceiling is to maintain the internal environment uniformity of the oyster mushroom cultivation house. When all the environment control equipment - including a unit cooler, an inlet fan, an outlet fan, an air circulation fan, and a humidifier - were operated simultaneously, the reported Root Mean Square (RMS) valuation the growing shelves were as follows: velocity 23.86%, temperature 6.08%, and humidity 2.72%. However, when only a unit cooler and an air circulation fan operated, improved RMS values on the growing shelves were reported as follows: velocity 23.54%, temperature 0.51%, and humidity 0.41%. Therefore, in order to maintain the internal environment uniformity of the mushroom cultivation house, it is essential to reduce the overall operating time of the inlet fan, outlet fan, and humidifier, while simultaneously appropriately manage the internal environment by using a unit cooler and an air circulation fan.

Load-Displacement Relationship of Passive Vibration Units Composed with a Spring and Vibration-Proof Rubbers (스프링과 방진고무가 융합된 제진장치의 하중-변위 관계)

  • Mun, Ju-Hyun;Im, Chae-Rim;Wang, Hye-Rin;Yang, Keun-Hyeok
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.6
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    • pp.226-234
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    • 2021
  • The objective of this study is to establish the fundamental design data for axial load-displacement relationship under axial monotonic or cyclic responses of seismic damping·isolation (SDI) units developed for ceiling structures. The main parameters include the installation of a spring, the number of rubber layer, prestress stress of bolts for connector between the spring and rubbers, and loading type. Test results showed that SDI units with a spring in the core and higher prestress stress of bolts tended to be higher stiffness at the ascending branch and more ductile behavior at the descending branch. This trends more notable for the specimens under monotonic load rather than cyclic loads. Consequently, the energy dissipation of SDI unit can be optimally designed with the following conditions: installation of a spring within 3-layer rubbers and prestress applied to the bolts at 10% of their yielding strength . When compared with the experimental tension capacity of the developed SDI units, the predictions by JIS B 2704-1 and KDS 31 00 are conservative under monotonic loading but higher by approximately 10% under cyclic loading.

Study of Optimal Light Scattering Pattern Design for Flat Lighting Device using Glass Light Guide (유리도광체를 이용한 평판조명용 광확산패턴의 최적설계 연구)

  • Han, Jeong-Min;Kim, Won-Bae
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.66 no.4
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    • pp.242-246
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    • 2017
  • In this study, it was investigated about optical simulation in high brightness and high uniformity general lighting using glass light guide plate. And we adopt edge-light emission type light plate. Edge-light type lighting has been used LCD application, especially note PC or smart phone backlight unit. Because it had the good properties such as slim shape and light weight. We thought this type was suitable for general lighting application such as wall attached type or ceiling mount type. But many of edge-light type lighting had problems. It called slanted output light rays. That was main key parameter how could control the direction of output light rays. We investigated the solution of this problems, using ray tracing method, we recognized the major fact of the solution relied on the geometric structure of diffusing dot shape. We set the conditions of aspect ratio in diffusing dot shape such as 0.5 to 1. And, at first, we designed diffusing dots shape based on the results of optical simulation and made specimen. as above condition, and acquired good result in confirming dots shape such as the value of the output rays's peak angle was around 75 degrees. And good light distribution characteristics were measured by slated spectro-radiometer. It was shown that the effective ways of designing light distribution characteristics using optical simulation such as ray tracing linear method for making general lighting using glass light guide plate.

Bright Light Therapy in the Morning or at Mid-Day in the Treatment of Non-Seasonal Bipolar Depressive Episodes (LuBi): Study Protocol for a Dose Research Phase I / II Trial

  • Geoffroy, Pierre Alexis;El Abbassi, El Mountacer Billah;Maruani, Julia;Etain, Bruno;Lejoyeux, Michel;Amad, Ali;Courtet, Philippe;Dubertret, Caroline;Gorwood, Philip;Vaiva, Guillaume;Bellivier, Frank;Chevret, Sylvie
    • Psychiatry investigation
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    • v.15 no.12
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    • pp.1188-1202
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    • 2018
  • Objective This study protocol aims to determine, using a rigorous approach in patients with bipolar disorder (BD) and non-seasonal major depressive episode (MDE), the characteristics of bright light therapy (BLT) administration (duration, escalation, morning and mid-day exposures) depending on the tolerance (hypomanic symptoms). Methods Patients with BD I or II and treated by a mood stabilizer are eligible. After 1 week of placebo, patients are randomized between either morning or mid-day exposure for 10 weeks of active BLT with glasses using a dose escalation at 7.5, 10, 15, 30 and 45 minutes/day. A further follow-up visit is planned 6 months after inclusion. Patients will be included by cohorts of 3, with at least 3 days of delay between them, and 1 week between cohorts. If none meet a dose limiting toxicity (DLT; i.e hypomanic symptoms), the initiation dose of the next cohort will be increased. If one patient meet a DLT, an additionnal cohort will start at the same dose. If 2 or 3 patients meet a DLT, from the same cohort or from two cohorts at the same dose initiation, the maximum tolerated dose is defined. This dose escalation will also take into account DLTs observed during the intra-subject escalation on previous cohorts, with a "Target Ceiling Dose" defined if 2 DLTs occured at a dose. Discussion Using an innovative and more ergonomic device in the form of glasses, this study aims to better codify the use of BLT in BD to ensure a good initiation and tolerance.

Constructability Analysis in Aged-Housing Remodeling Demolition Work for Maximizing Waste Recycling (폐기물 재활용성 향상을 위한 리모델링 철거공사의 시공성 평가 및 사례적용)

  • Chae, Seong-Hyun;Kim, Ki-Hyun;Cha, Hee-Sung;Kim, Kyung-Rai;Han, Ju-Yeoun
    • 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.

A Study on People Counting in Public Metro Service using Hybrid CNN-LSTM Algorithm (Hybrid CNN-LSTM 알고리즘을 활용한 도시철도 내 피플 카운팅 연구)

  • Choi, Ji-Hye;Kim, Min-Seung;Lee, Chan-Ho;Choi, Jung-Hwan;Lee, Jeong-Hee;Sung, Tae-Eung
    • Journal of Intelligence and Information Systems
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    • v.26 no.2
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    • pp.131-145
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    • 2020
  • In line with the trend of industrial innovation, IoT technology utilized in a variety of fields is emerging as a key element in creation of new business models and the provision of user-friendly services through the combination of big data. The accumulated data from devices with the Internet-of-Things (IoT) is being used in many ways to build a convenience-based smart system as it can provide customized intelligent systems through user environment and pattern analysis. Recently, it has been applied to innovation in the public domain and has been using it for smart city and smart transportation, such as solving traffic and crime problems using CCTV. In particular, it is necessary to comprehensively consider the easiness of securing real-time service data and the stability of security when planning underground services or establishing movement amount control information system to enhance citizens' or commuters' convenience in circumstances with the congestion of public transportation such as subways, urban railways, etc. However, previous studies that utilize image data have limitations in reducing the performance of object detection under private issue and abnormal conditions. The IoT device-based sensor data used in this study is free from private issue because it does not require identification for individuals, and can be effectively utilized to build intelligent public services for unspecified people. Especially, sensor data stored by the IoT device need not be identified to an individual, and can be effectively utilized for constructing intelligent public services for many and unspecified people as data free form private issue. We utilize the IoT-based infrared sensor devices for an intelligent pedestrian tracking system in metro service which many people use on a daily basis and temperature data measured by sensors are therein transmitted in real time. The experimental environment for collecting data detected in real time from sensors was established for the equally-spaced midpoints of 4×4 upper parts in the ceiling of subway entrances where the actual movement amount of passengers is high, and it measured the temperature change for objects entering and leaving the detection spots. The measured data have gone through a preprocessing in which the reference values for 16 different areas are set and the difference values between the temperatures in 16 distinct areas and their reference values per unit of time are calculated. This corresponds to the methodology that maximizes movement within the detection area. In addition, the size of the data was increased by 10 times in order to more sensitively reflect the difference in temperature by area. For example, if the temperature data collected from the sensor at a given time were 28.5℃, the data analysis was conducted by changing the value to 285. As above, the data collected from sensors have the characteristics of time series data and image data with 4×4 resolution. Reflecting the characteristics of the measured, preprocessed data, we finally propose a hybrid algorithm that combines CNN in superior performance for image classification and LSTM, especially suitable for analyzing time series data, as referred to CNN-LSTM (Convolutional Neural Network-Long Short Term Memory). In the study, the CNN-LSTM algorithm is used to predict the number of passing persons in one of 4×4 detection areas. We verified the validation of the proposed model by taking performance comparison with other artificial intelligence algorithms such as Multi-Layer Perceptron (MLP), Long Short Term Memory (LSTM) and RNN-LSTM (Recurrent Neural Network-Long Short Term Memory). As a result of the experiment, proposed CNN-LSTM hybrid model compared to MLP, LSTM and RNN-LSTM has the best predictive performance. By utilizing the proposed devices and models, it is expected various metro services will be provided with no illegal issue about the personal information such as real-time monitoring of public transport facilities and emergency situation response services on the basis of congestion. However, the data have been collected by selecting one side of the entrances as the subject of analysis, and the data collected for a short period of time have been applied to the prediction. There exists the limitation that the verification of application in other environments needs to be carried out. In the future, it is expected that more reliability will be provided for the proposed model if experimental data is sufficiently collected in various environments or if learning data is further configured by measuring data in other sensors.