• Title/Summary/Keyword: Storage depth

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Quantitative Comparisons of Soil Carbon and Nutrient Storage in Larix leptolepis, Pinus densiflora and Pinus rigitaeda Plantations

  • Kim, Choonsig;Cho, Hyun-Seo
    • The Korean Journal of Ecology
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    • v.27 no.2
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    • pp.67-71
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    • 2004
  • This study was carried out to evaluate soil carbon and nutrient storage of three adjacent coniferous plantations (Larix leptolepis, Pinus densiflora and Pinus rigitaeda) growing on a similar site with a same planting age (42-year old) in the Sambong Exhibition Forests, Hamyang-gun, Gyungsangnam-do. The soil carbon concentration among three plantations was not significantly different in 0∼10cm soil depth, but other two depths (10∼20cm and 20∼30cm) showed higher carbon concentration in P. densiflora plantation than the other two plantations. The exchangeable cation concentrations (Ca and Mg) in 0∼10cm depth were significantly lower in L. leptolepis plantation than in the other two plantations, while nitrogen and phosphorus concentrations were not significantly different among three plantations except for nitrogen at 10∼20cm depth in P. rigitaeda plantation. Soil carbon storage in 0∼20cm depth of three plantations was unaffected by the stand types. Soil nutrient storage was not significantly different at each depth except for nitrogen storage at 10∼20cm depth in P. rigitaeda plantation because of the variation of bulk density and coarse fragment. This result demonstrates that soil carbon and nutrient concentrations among the plantations on a similar soil condition can be altered significantly by tree species effects over 40 years after plantation establishment.

Optimizing Fsync Performance with Dynamic Queue Depth Adaptation

  • Park, Daejun;Kim, Min Ji;Shin, Dongkun
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.15 no.5
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    • pp.570-576
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    • 2015
  • Existing flash storage devices such as universal flash storage and solid state disk support command queuing to improve storage I/O bandwidth. Command queuing allows multiple read/write requests to be pending in a device queue. Because multi-channel and multi-way architecture of flash storage devices can handle multiple requests simultaneously, command queuing is an indispensable technique for utilizing parallel architecture. However, command queuing can be harmful to the latency of fsync system call, which is critical to application responsiveness. We propose a dynamic queue depth adaptation technique, which reduces the queue depth if user application is expected to send fsync calls. Experiments show that the proposed technique reduces the fsync latency by 79% on average compared to the original scheme.

Evaluation of Canister Weld Flaw Depth for Concrete Storage Cask (콘크리트 저장용기의 캐니스터 용접부 결함깊이 평가)

  • Moon, Tae-Chul;Cho, Chun-Hyung;Jung, Sung-Hun;Lee, Young-Oh;Jung, In-su
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.1
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    • pp.91-99
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    • 2017
  • Domestically developed concrete storage casks include an internal canister to maintain the confinement integrity of radio-active materials. In this study, we analyzed the depth of flaws caused by loads that propagate canister weld cracks under normal, off-normal and accident conditions, and evaluated the maximum allowable weld flaw depth needed to secure the structural integrity of the canister weld and to reduce the welding time of the internal canister lid of the concrete storage cask. Structural analyses for normal, off-normal and accident conditions were performed using the general-purpose finite element analysis program ABAQUS; the allowable flaw depth was assessed according to ASME B&PV Code Section XI. Evaluation results revealed an allowable canister weld flaw depth of 18.75 mm for the concrete storage cask, which satisfies the critical flaw depth recommended in NUREG-1536.

Studies on t Sediment Deposit and Storage Capacity of the Honam Province (호남지방의 저수지의 매몰상황과 저수량에 관한 조사연구)

  • 이창구
    • Journal of the Korean Professional Engineers Association
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    • v.3 no.10
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    • pp.7-17
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    • 1970
  • Fourteen reservoirs maintained by the local land improvement associations in the province of Chullabuk-Do and 20 reservoirs maintained by those in the province of Chullanam-Do, were surveyed in connection with a correction between storage capacity and sediment deposit. In addition to this survey, 3347 of small scale reservoirs, that lie scattered around in the above mentioned two provinces were investigated by using existing records pertaining to storage capacity in the office of City and Country, respectively. According to this inrestigation. the following conclusions are derived. 1. A sediment deposition rate is high, being about 10.63m$^3$/ha of drainage area, and resulting in the average decrease of storage capacity by 27.5%. This high rate of deposition could be mainly attributed to the severe denudation of forests due to disorderly cuttings of trees. Especially, in small scale reservoirs, an original average design storage depth of 197mm in irrigation water depth is decreased to about 140mm. 2. An average unit storage depth of 325.6mm as the time of initial construction is decreased to 226mm at present. This phenomena causes a greater shortage of gation water, since it was assumed that original storage quantity itself was already in short.

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Numerical Analysis of Fluid and Thermal Characteristics on Live Fishing Tank of Small Fishing Boat (소형어선용 어창내의 열 유동특성 해석)

  • 한인근;문춘근;김재돌;윤정인
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.6
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    • pp.1324-1329
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    • 2001
  • The depression of the external situation like the departure of WTO system and the plan of EEZ proclaim is forcing fishery into improving their fishing condition. By this international and domestic circumstance, development of the sea water cooling apparatus for fish hold storage is demanded sincerely. This study represents the thermal characteristics of the fish hold storage during transportation. The numerical analysis in this study is the finite volume method with the SIMPLE computational algorithm to study the seawater flow behavior in the fish hold storage. The computation were carried out with the variations of the circulating flow velocity and depth of fish hold storage. As the result of the three dimensional simulations, the mean temperature doesn't almost change by the circulating flow rate. find the mean temperature is suddenly changed by the ratio of depth of fish hold storage.

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Effects of Cutting Size and Planting Depth on Growth and Yield in Late-Cultivation of Sweet Potato (고구마 만기재배에서 생육 및 수량에 미치는 삽수크기 및 삽식깊이의 영향)

  • Lee, Seung-Yeob;Kim, Tae-Hwan;Lee, Na-Rha;Lee, Ear-Jin;Bae, Jong-Hyang
    • Journal of Bio-Environment Control
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    • v.19 no.3
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    • pp.153-158
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    • 2010
  • To obtain the basic information for late-cultivation of sweet potato [Ipomoea hatalas (L.) Lam. cv. 'Jinhongmi'], vine growth and storage root yield were investigated in variously cutting sizes (10, 20, and 30 cm) and planting depths (1~4 nodes in 30 cm vine) using black-film vinyl mulching cultivation ($75{\times}25\;cm$ planting density, June 20). At 30 days after planting, main vine length, number of node, and vine fresh weight were significantly affected by the cutting length, and these were significantly different 10 and 30 cm at 120 days. The vine elongation affected by planting depths showed the best growth in 2-nodes planting depth and the lowest growth in 4-nodes planting depth at 30 days, but the vine growth was not significantly different among planting depths at 120 days. Number of storage root per plant, weight of storage root per plant, mean weight of storage root and yield of storage root were increased in longer cutting length, and those in 10 cm cutting length were significantly reduced compared to the 20 and 30 cm cutting length. Number of storage root per plant in the deeper planting was much increased, but mean weight of storage root was much decreased. Yield of storage root per 10a was highest in 3-nodes planting depth. Therefore, planting methods by cutting length over 20 cm and planting depth of 2~3 nodes in late-cultivation of sweet potato will be more efficient to improve the vine growth and storage root yield.

A Study on Stroage of Chicken Eggs from Poultry Farms (식란의 보전성에 관한 연구)

  • 조태행;인영민;정갑수;남궁선
    • Journal of Food Hygiene and Safety
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    • v.4 no.1
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    • pp.29-36
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    • 1989
  • In order to investigate the Storage time of chicken eggs, several physico-chemical tests from chicken eggs store at 5, 13 and 27$^{\circ}C$ were examined. Egg samples were collected from six poultry farms. Egg stored at 5$^{\circ}C$ based on the depth of air cell and specific gravity, were all acceptable until 17 days ; on the egg yolk coefficient and pH of the egg white and egg yolk until about 10 days. Egg stored at 13$^{\circ}C$, based on the depth of air cell. were acceptable by about 10 days of storage, but on the other physico-chemical tests by about 7 days. Egg samples stored at room temperature(about 27$^{\circ}C$) base on the depth of air cell, were acceptable by about 5 days of storage ; on the specific gravity by 4 days ; and on the egg yolk coefficient and pH of the egg yolk and egg white by 3 days. The results of this study showed that egg stored at 5$^{\circ}C$ were considered acceptable by 10 days of storage ; at 13$^{\circ}C$ by 7 days ; at room temperature (27$^{\circ}C$) by 3 days.

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A Study on Sediment Deposite in Reservoir (저유수량의 소실률 조사연구)

  • 엄태영
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.10 no.1
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    • pp.1413-1419
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    • 1968
  • Yochon reservoir was consturcted with an original storage capacity of 202.7 chung-meters. This reservoir receives the water from watershed area of 933.0 chungbo and has irrigated area of 478.0 chungbo. In 1967 a detailed capacity survey of this reservoir was carried out by a new depth-recorder under the scheme of reservoir sedimentation of Agricultural Engineering Research Center. Significant findings are 1. The capacity of the reservoir for the water storage has been reduced by 8.9%(18.066 chung-meters out of the 202.7 chung-meters) since its construction, a period of just 39.0 years. 2. The sediment accumulation in the reservoir represents an average annual soil loss of 0.496mm depth(0.463 chung-meters) of soil from the watershed area of 933.0 chungbo. Eventually the capacity of the reservoir for the water storage will be reducing by about 25%(50.7 chung-meters out of the 202.7 chung-meters)in one hundred years since its construction. We have to set up controlling projects for those reservoir protections from the sediment, soil loss, and other failures. The depth recorder is very useful, convenient, and accurate machine for surveys of reservoir capacity and other river surveys.

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Seismic reliability of concrete rectangular liquid-storage structures

  • Cheng, Xuansheng;He, Peicun;Yu, Dongjiang
    • Structural Engineering and Mechanics
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    • v.70 no.5
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    • pp.563-570
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    • 2019
  • To analyze the seismic reliability of concrete rectangular liquid storage structures (CRLSSs), assuming that the wall thickness and internal liquid depth of CRLSSs are random variables, calculation models of CRLSSs are established by using the Monte Carlo finite element method (FEM). The principal stresses of the over-ground and buried CRLSSs are calculated under three rare fortification intensities, and the failure probabilities of CRLSSs are obtained. The results show that the seismic reliability increases with the increase of wall thickness, whereas it decreases with the increase of liquid depth. Between the two random factors, the seismic reliability of CRLSSs is more sensitive to the change in wall thickness. Compared with the over-ground CRLSS, the buried CRLSS has better reliability.

Thermal Energy Storage and Release Characteristics of the Soil in the Greenhouse Equipped with Heat Pump and Latent Heat Storage System (열펌프-잠열축열 시스템 온실에서 토양의 열저장 및 방열 특성)

  • 노정근;송현갑
    • Journal of Biosystems Engineering
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    • v.27 no.1
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    • pp.39-44
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    • 2002
  • In order to obtain the information of bio-environment control, the thermal characteristics of soil in the greenhouse heated by the heat pump and latent heat storage system were experimentally analyzed. The experimental systems were composed of the greenhouse with a heat pump and a latent heat storage system (system I), the greenhouse with a heat pump (system II), the greenhouse with a latent heat storage system (system III), and the greenhouse without auxiliary heating system (system IV). The thermal characteristics experimentally analyzed in each system were temperature of soil layers, soil heat storage and release, soil heat capacity and soil heat storage ratio. The results could be summarized as follows. 1. Time to reach the highest temperature at 20cm deep in soil layers of the crop routs in case of system I was shown to be delayed by 6 hours in comparison to the time of the highest temperature at the soil surface. 2. In the clear winter days, the stored heat capacity values fur the system I and the system II were shown to be 22.3% and 11.0% higher than the released heat capacity respectively, and the stored heat capacity values for the system III and the system IV were shown to be 6.2% and 29.6% lower than the released heat capacity respectively This confirms that the system I provided the best heat storage effect. j. The heat quantity values stored or released were shown to be highest at 5 cm depth of soil layers. And it was reduced with increasing of depth of soil layers until 20 cm and was not changed under the soil layer of 20 cm depth. 4. The heat absorption rates of soil, the ratio between supplied and stored heat energy, fur both the system I and system II were lower than 23%.