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Energy and Air Quality Benefits of DCV with Wireless Sensor Network in Underground Parking Lots

  • Cho, Hong-Jae;Jeong, Jae-Weon
    • International Journal of High-Rise Buildings
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    • v.3 no.2
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    • pp.155-165
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    • 2014
  • This study measured and compared the variation of ventilation rate and fan energy consumption according to various control strategies after installing wireless sensor-based pilot ventilation system in order to verify the applicability of demand-controlled ventilation (DCV) strategy that was efficient ventilation control strategy for underground parking lot. The underground parking lot pilot ventilation system controlled the ventilation rate by directly or indirectly tracking the traffic load in real-time after sensing data, using vehicle detection sensors and carbon monoxide (CO) and carbon dioxide ($CO_2$) sensor. The ventilation system has operated for 9 hours per a day. It responded real-time data every 10 minutes, providing ventilation rate in conformance with the input traffic load or contaminant level at that time. A ventilation rate of pilot ventilation system can be controlled at 8 levels. The reason is that a ventilation unit consists of 8 high-speed nozzle jet fans. This study proposed vehicle detection sensor based demand-controlled ventilation (VDS-DCV) strategy that would accurately trace direct traffic load and CO sensor based demand-controlled ventilation (CO-DCV) strategy that would indirectly estimate traffic load through the concentration of contaminants. In order to apply DCV strategy based on real-time traffic load, the minimum required ventilation rate per a single vehicle was applied. It was derived through the design ventilation rate and total parking capacity in the underground parking lot. This is because current ventilation standard established per unit floor area or unit volume of the space made it difficult to apply DCV strategy according to the real-time variation of traffic load. According to the results in this study, two DCV strategies in the underground parking lot are considered to be a good alternative approach that satisfies both energy saving and healthy indoor environment in comparison with the conventional control strategies.

Effect of Paclobutrazol on Growth, and High Temperature and Drought Stress in Perennial Ryegrass (Paclobutrazol 처리가 Perennial Ryegrass의 생육 및 고온과 건조 Stress에 미치는 영향)

  • 김태일;구자형;원동찬
    • Asian Journal of Turfgrass Science
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    • v.3 no.1
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    • pp.24-33
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    • 1989
  • This study was conducted to investigate the effect of paclobutrazol [(2 RS , 3 RS )1-(4- chlor-ophenyl )-4, 4- dimethyl -2- (1, 2, 4- triazol -1- yl )- pentan -3-01] on the tolerance of hi-gh temperature and drought stress as related to growth retardation , iranspiration rate , soil water content , nitrogen level and photosynthetic rate in perennial ryegrass ( Loliurn perenne L . ' Omega H , ). Plants were given a 30 ml soil drench of paclohutrazol at the concentrations of 0, 0.01, 0.1, 1.0, 10.. 0, mg / 6 .5cm- diameter pot . The rcsults were as follows : 1. Increasing concentrations of paclohutrazul reduced plant height , leaf area , fresh weight and dry weight , hut increased chlorophyll content per unit area . The number of tillers and leaf width were not affected hy the paclobutrazol concentrations . 2. The proper concentration of paclohatrazol on growth retardation in perennial ryegrass was about I mq /pot , hut leaf deformity and severe growth retardation were shown at high concentration of 10 mq / pot . 3. Perennial ryegrasses grown at 30˚C were shown significantly short plant height and low leaf nitrogen level compared with those grown at 20˚C. Increasing concentrations of paclohutrazol at 20˚C increased nitrogen level hut it could not increase nitrogen level at 30˚C . 4. During the drought stress , increasing temperatures significantly promoted transpiration rate and wilting time . It took about 5 days at 20˚C and 3 days at 30˚C to reach wilting time of leaves from water stress treatment . Soil water contents at wilting time of non-treated controls were averaged 6. 871% at 20˚C and 6. 17% at 30˚C 5. Paclohutrazol reduced transpiration rate at high temperature and drought stress . Wilting appeared at the lower water content of soil according to increasing concentrations of paclobutrazol at 30˚C hut there were no differences among concentrations of at 20˚C. 6.Paclohutrazol treatment at 1 rag /pot reduced injury rate of leaves from 67.1 % and 100 % in control plants to 15.7% and 80% at 20˚C and 3010, respectively. 7. Photosynthetic rate per unit area was significantly reduced at high temperature . Paclohutrazol stimulated photosynthetic rate with increase of concentrations at 20˚C but there was no increasing effect at 30˚C.

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Concept of Adaptability for Heavy nitrogen in view of Nitrogen Metabolism -I. Adaptability for heavy nitrogen under the field (내비성(耐肥性)에 관(關)한 질소대사적(窒素代謝的) 개념(槪念) -I. 포장조건하(圃場條件下)의 내비성(耐肥性))

  • Yoon, Jong Hyuk;Cho, Sung Jin;Park, Hoon
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.3
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    • pp.173-177
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    • 1973
  • The concept of "adaptability to heavy nitrogen" of rice plant was reconsidered in view of productivity with Jinheung (leading local variety) and IR667 (semi tropical variety) under the field condition. The results are as follows; 1. IR667 had higher yield and leaf area index at high nitrogen level than Jinheung. 2. IR667 increased more panicles, spikelets, filled grain ratio and grain weight by increasing nitrogen. 3. IR667 showed higher productive efficiency of grain and leaf area per unit nitrogen. 4. IR667 was higher in the productive efficiency of grain per unit leaf area. 5. IR667 appeared as panicle and spikelet number type and Jinheung as grain weight type according to yield components. 6. These results indicate that IR667 has greater productive adaptability to heavy nitrogen under the field condition.

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Stratigraphy and Paleoceanography of deep-sea core sediments from the Korea Deep Ocean Study (KODOS)-97 Area, Northeast Equatorial Pacific (북동태평양 KODOS-97지역 주상 퇴적물의 층서 및 고해양학적 연구)

  • Park, Jeong-Hee;Kim, Ki-Hyune
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.1
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    • pp.50-62
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    • 1999
  • Sediment core samples recovered from the Korea Deep Ocean Study (KODOS)-97 area were divided into two or three units according to their distinct changes in sediment colors and chemical and physical properties. Analyses of radiolarian faunas in the sediments and $^{10}Be$ ratios in each unit were performed to reveal stratigraphic and paleoceanographic history of the study area. In the upper part of the sediments, Tertiary radiolarians were mixed at various proportions with Quaternary assemblages probably by reworking process of bottom current and benthic animals. Dissolution of radiolarians was severe in deeper depth and in the Unit III, only few of the fragments of corroded Tertiary radiolarians were detectable. The mid layer of the Unit I belonged to Collosphaera invaginata Zone, the time period of 0.21 Ma. The Unit II belonged to Collosphaera tuberosa Zone with the time period younger than 0.42 Ma which was observed above the Stylatractus universus Zone. The Unit III is assigned to Tertiary, which is younger than the Late Eocene. Composition analyses of radiolarian assemblage and $^{10}Be$ ratio data indicated hiatus periods of more than 3 My between late of Middle Miocene and Pliocene resulting from erosion and dissolution caused by Antarctic Bottom Water. Stratigraphic evidence from radiolaria was well correlated with $^{10}Be$ data. Sedimentation rate during Quaternary can be suggested as 0.15-0.5 mm per 1000 years. Dominance of warm-water radiolaria species and the results reflected minimum climatic changes of tropical conditions.

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Generation of Free Chlorine Using $RuO_2$/ Ti Electrode with Various Amount of Ru (Ru 코팅량에 따른 $RuO_2$/Ti 전극의 염소 발생)

  • Lee, JunCheol;Pak, DaeWon
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.11
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    • pp.715-719
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    • 2012
  • We investigated the effects of electrochemical characteristics and generation of chlorine by the different amount of Ru coating which was prepared for $RuO_2$/Ti electrode coated with 1.5 mg, 2.5 mg, 5.5 mg, 8.5 mg Ru per unit area ($cm^2$). As a Result of the cycle voltammetry experiments, chlorine overvoltage of Ru-coated electrodes showed to be the nearly sustained value of approximately 1.15V (vs. Ag/AgCl). By contrary, According to the results of the AC impedance spectroscopy and potentiodynamic polarization tests, the amount of Ru per unit area ($cm^2$) included 2.5 mg, 3.5 mg as $RuO_2$/Ti offered the highest levels of durability which was electrode resistance and corrosion rate appeared to be $0.4582{\Omega}$, $0.5267{\Omega}$ and 0.082 mm/yr, 0.058 mm/yr, respectively. It was also observed that generation of chlorine coated with 3.5 mg per unit area ($cm^2$) was the highest value of 15.2 mg/L.

A Study on Energy Efficiency Improvement through Building Insulation Diagnosis (건축물 단열 진단을 통한 에너지 효율 개선에 관한 연구)

  • Cho, Kwangmoon
    • Journal of Internet of Things and Convergence
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    • v.7 no.3
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    • pp.9-14
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    • 2021
  • This paper discovers the energy loss factors through the insulation diagnosis of houses or buildings, and proposes directions for energy efficiency improvement. The energy efficiency factor of a building consists of insulation diagnosis, thermal bridge diagnosis, window diagnosis, airtight diagnosis, and equipment diagnosis. Among the residents and facilities in the energy welfare blind spot, an energy efficiency diagnosis was conducted for one senior citizen building located in Naju-si, Jeollanam-do, and energy efficiency diagnosis was conducted after insulation was installed. Energy measurement, diagnosis and analysis were performed using the IoT-based integrated wired/wireless energy diagnosis platform, Energy Finder. As a result of comparison, an overall energy saving rate of 16.38% was achieved. Annual heating energy consumption per unit area decreased from 333.51kWh before construction to 277.35kWh after construction, and annual cooling energy consumption per unit area decreased from 5.51kWh before construction to 5.22kWh after construction. The annual primary energy consumption per unit area decreased from 464.52kWh before construction to 403.69kWh after construction, and the annual energy cost was reduced from 3,063,307.14 won before construction to 2,641,072.49 won after construction. The additional improvement work is needed on the standards affecting energy efficiency other than insulation.

Responses of Growth and Yield Characters on Planting Density in Determinate and Indeterminate Soybeans (재식밀도에 따른 유ㆍ무한 신육형 콩의 생육 및 수량형질 반응)

  • Kim, Hong-Sig;Hong, Eun-Hi;Park, Sang-Il;Park, Yeon-Kyu
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.38 no.2
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    • pp.189-195
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    • 1993
  • This study was conducted to obtain the .basic informations for developing soybean varieties and mechanizing cultivation at the Crop Experiment Station, Rural Development Administration, Suwon, Korea in 1990. Two determinate soybean varieties, Hwangkeurnkong and Jangyeobkong, and two indeterminate soybean varieties, Clark and Williams were planted at three planting densities (33,22,16 plants / $m^2$). Number of branches and number of nodes on branches per unit area ($m^2$) were greater in determinate varieties than in indeterminate ones, and number of nodes on mainstem were greater in indeterminate varieties than in determinate ones. The higher planting density increased those characters. Seed weight per unit area ($m^2$) was higher in determinate varieties than in indeterminate ones, and it was great at the higher planting density. Indeterminate varieties showed greater mainstem dependence rate for yield components than determinate ones did. Harvest index was higher in indeterminate varieties than in determinate ones. The lower planting density increased harvest index. Stem dry weight per unit area($m^2$) was greater in determinate varieties than in indeterminate ones, and it was greater at the higher planting density. Variations among plants were great in the order of branch-related yield characters > total plant-re-lated yield characters > mainstem-related yield characters > morphological characters of mainstem and 100 seed weight. Difference between determinate and indeterminate varieties was significant in branch-related characters. Indeterminate varieties showed greater variations than determinate ones did in branch-related yield characters at different planting densities.

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A Study on the Changes of Facility Guidelines and Improvement of Architectural Planning on the Wards in the Public District General Hospitals (지역거점 공공병원 병동부의 시설기준 변화와 건축계획 개선에 관한 연구)

  • Kim, Kiyon;Choi, Kwangseok
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.24 no.3
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    • pp.7-15
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    • 2018
  • Purpose: The purpose of this study is to suggest the improvement of the architectural planning of public hospitals by analyzing the contents of the architectural planning and the trend of the recent ward planning. Methods: The study method was the drawing analysis of the wards in the public hospitals where facilities were improved including the ward-related literature survey. The scope of the study was the general wards. Results: As a result of the study, the area composition of the ward area, the number of beds per nursing unit, the floorplan types, and the unit space planning which is included the room composition, the room size, the bed clearance areas, and the improvements of the nursing space were suggested. Implications: The result of this research would be useful as a reference to design nurse area in the wards.

A Study on the Estimation model of the Amount of the Electric Energy Consumption according to the Apartment Heating Type (공동주택 난방방식별 전력에너지 소비량 추정모델 작성 연구)

  • Lee, Kang-Hee;Yang, Jae-Hyuk;Ryu, U-Sang
    • KIEAE Journal
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    • v.10 no.1
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    • pp.57-64
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    • 2010
  • Electric energy is indispensible of the development of the industrial and living sector. Among the energy sectors, the building area shares 20% of the produced electric power in Korea. As we plan to supply the apartment, we need to forecast the required amount of the electric energy and supply the infrastructure to apartment for the lighting, cooling. Nonetheless, it is not easy to forecast the required amount of the electric energy, considering the management aspect, building physical aspect and social-geographic aspect. In this paper, it studied the estimation model of the electric energy, reflecting the affecting variables such as total area, number of household, geography and so on. The estimation model is proposed in 3-types which explained in central heating, individual heating and district heating, and each type have two estimation model, reflecting the affecting variable and corelation between variables to eliminate the muticolinearity. The unit of electric energy consumption per area and year is similar in three heating type and the results are as follows; the central heating is $34.446kWh/yr{\cdot}m^2$, individual type is $35.756446kWh/yr{\cdot}m^2$ and district heating is $34.285446kWh/yr{\cdot}m^2$.

An easy-to-use design procedure for multipass plate heat exchangers based on the performance plots (성능선도에 의한 다통로 판형열교환기의 간이설계법)

  • 유호선;이근휘;방보청
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.2
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    • pp.250-261
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    • 1999
  • Based on a set of performance plots relating the design variables to the imposed conditions, an easy-to-use and versatile design procedure for chevron-type multipass plate heat exchangers is developed. In order for the present procedure to cover multipass with unequal passes and non-unity ratio of heat capacity rate, each stream number of transfer unit is adopted as the basic design variable instead of the exchanger number of transfer unit. It is found that there exists a unique relation between the stream and exchanger number of transfer units regardless of the chevron angle and the plate length. In addition, for a given value of the pressure drop the heat transfer area per unit mass flow rate can be expressed in terms of the stream number of transfer unit only. These two relationships in the form of simple plots constitute the framework of design. The sample results in comparison with the available data indicate that the present procedure includes the previous ones as a subset, and that every design method is affected essentially by the selection of specific correlations for the heat transfer coefficient and the friction factor.

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