• Title/Summary/Keyword: Deposit

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Optimum PVD installation depth for two-way drainage deposit

  • Chai, J.C.;Miura, N.;Kirekawa, T.;Hino, T.
    • Geomechanics and Engineering
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    • v.1 no.3
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    • pp.179-191
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    • 2009
  • For a two-way drainage deposit under a surcharge load, it is possible to leave a layer adjacent to the bottom drainage boundary without prefabricated vertical drain (PVD) improvement and achieve approximately the same degree of consolidation as a fully penetrated case. This depth is designated as an optimum PVD installation depth. Further, for a two-way drainage deposit under vacuum pressure, if the PVDs are fully penetrated through the deposit, the vacuum pressure will leak through the bottom drainage boundary. In this case, the PVDs have to be partially penetrated, and there is an optimum installation depth. The equations for calculating these optimum installation depths are presented, and the usefulness of the equations is studied by using finite element analysis as well as laboratory model test results.

MINERALOGICAL, FLUID INCLUSION AND ISOTOPE STUDIES AT THE CINEAM EPITHERMAL GOLD DEPOSIT WEST- JAVA(Review on epithermal gold deposit in Java)

  • Widi, Bambang-Nugroho;Sunuhadi, Dwi-Nugroho;Bambang-Setiawan
    • Proceedings of the KSEEG Conference
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    • 2003.04a
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    • pp.19-19
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    • 2003
  • Cineam gold deposit is one of an epithermal gold deposit of Low Sulfidation type, which is located in the Sunda-Banda magmatic Arc Zone. Its existence in this region has led to a new concept or few point on the Sunda - Banda Magmatic Arc. Even the deposit is classified as a small scale in mine, however, mineralogically, fluid inclusion and isotopes studies are very interesting to be studied. (omitted)

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Fabrication of Chromium-based Double Layered Deposit (크롬계 이중도금층 제조 및 특성평가)

  • Park, Sang-Eon;Kim, Dong-Su;Kim, Man;Jang, Do-Yeon;Gwon, Sik-Cheol
    • 연구논문집
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    • s.31
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    • pp.127-133
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    • 2001
  • In chromium electrodeposition, crack is inevitably accompanied by chromium layer. Behavior of crack formation and crack density were different from the plating conditions such as current density, temperature, waveform of applied current and so on. And cracks have an influence on the corrosion resistance of chromium deposit, because corrosion occurs through the network of cracks between deposit and substrate. Therefore, many researches have been achieved in order to remove the cracks in chromium deposit. Formation of double layers, Cr/Cr and Ni/Cr were investigated to increase corrosion resistance of chromium deposit in this study. As pretreatment prior to outer chromium coating, acid pickling and current control method were examined. Cracks in cross-section of each sample were observed with SEM and CASS(Copper modified acetic acid salt spray) test was performed to evaluate corrosion resistance. It was found that corrosion resistance of Cr/Cr and Ni/Cr double layers were superior to Cr or Ni single layer from the results of CASS test.

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Study on the Behavior of Sabkha Deposit during Dynamic Compaction (사브카 지반 동다짐 공법 적용 시 지반거동 분석)

  • Moon, Joon-Shik
    • Journal of the Korean Geosynthetics Society
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    • v.16 no.4
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    • pp.103-111
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    • 2017
  • Saudi Arabia coastal area is highly valuable construction as a flat area covered by sabkha deposit. However, sabkha deposit has some geotechnical problems because of high groundwater level, high salt contents in groundwater, loose density, and possibility of collapsible settlement due to presence of crystals vulnerable to moisture, and ground improvement is needed to improve the bearing capacity. In this study, the characteristics of the sabkha soils in the coastal area of Saudi Arabia were analyzed and the applicability of dynamic compaction method was evaluated. Parametric study was conducted to analyze the behavior of sabkha deposit during dynamic compaction. The appropriateness of the proposed analytical solutions to estimate the depth of improvement was evaluated, and the troubles and notes in applying dynamic compaction in sabkha deposit were discussed.

Survey of Borate deposit in Northern Argentina: Salinas Grandes Borate deposit (북부 아르헨티나 붕산염 광상 조사: 살리나스그란데스 광상을 중심으로)

  • Pak, Sang-Joon; Lee, Han-Yeang
    • Journal of the Korean earth science society
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    • v.30 no.7
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    • pp.801-809
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    • 2009
  • The Salinas Grandes borate deposit located in Jujuy state, northern Argentina can be categorized into the playatype evaporite deposit. Major borate mineral is ulexite ($NaCaB_5O_9{\cdot}H_2O$), which boron could be originated from volcanic rocks nearby playa. The eastern part of the Jujuy state in northern Argentina belongs to the Altiplano-Puna platform which shows high altitude and semiarid climate. Lots of Mesozoic and Cenozoic volcanics that are source of boron as well as playas that are the basin for borate precipitation in the area are essential for boron evaporite deposit. Therefore, the extensive explorations for the playa-type evaporite deposit are need.

The Effect of Current on Characteristics of Stellite 12 Alloy Overlayer by PTA Process (PTA법에 의한 스텔라이트 12 합금 육성층의 특성에 미치는 전류의 영향)

  • Jung, B.H.;Kim, M.K.;Ahan, Y.S.;Kim, M.Y.;Lee, S.Y.
    • Journal of Power System Engineering
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    • v.5 no.3
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    • pp.88-94
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    • 2001
  • Stellite 12 alloy-powders were overlaid on 410 stainless steel valve seat using plasma transferred arc(PTA) process. Variation of the microstructure, hardness, wear and corrosion of overlaid deposit with current change was investigated. The deposit showed hypoeutectic microstructure, which was consisted of primary cobalt dendrite and networked $M_7C_3$ type eutectic carbides. As current increased, the amount of eutectic carbide decreased and its dendritic secondary arm spacing increased. Hardness of the deposit was decreased with increase of current. Stress relief heat treatment at $600^{\circ}C$ for two hours resulted in slight increase of hardness in the deposit and showed uniform hardness distribution in base metal without any hardened layer in HAZ. Specific wear decreased with increase of sliding distance. The deposit of high hardness with a lot of eutectic carbide showed relatively low specific wear. Initial corrosion current density of the deposit in 0.1N sulfuric acid was lower than those of 410 stainless steel, and showed a little variation with PTA current.

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A Study on the Piston Temperatures and Carbon Deposit Formation in LPG Fuelled Engine (LPGdusfy 엔진의 피스톤온도 및 카본디포짓 형성에 관한 연구)

  • 민병순;최재권;박찬준
    • Transactions of the Korean Society of Automotive Engineers
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    • v.6 no.2
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    • pp.100-106
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    • 1998
  • The wide open throttle performance and piston temperatures were measured by the change of fuel : gasoline and liquefied petroleum gas(LPG). Bench test method was developed and experimented to study the effect of temperature on the formation of carbon deposit. The bench test results were confirmed by measuring the piston temperature and observing the deposit production rate at an actual engine running condition. Results show that if the fuel of spark ignition engine is changed from gasoline to LPG, the output power decreases about 10% and the piston temperatures increase about 40~55$^{\circ}C$. In actual engine tests, because of this temperature increase, it was observed that the quantity of carbon deposit in the top ring groove increased in a big degree. Consuquently, it is known that the fing sticking may occur if the gasoline engine was rebuilt to LPG fuelled engine. Therefore, in order to preserve the durability of LPG fuelled engine, it is necessary to lower the piston temperature by hardware modificationor to reduce the carbon deposit by the improvement of engine oil.

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Electrokinetic Removal and Removal Characteristics of Heavy Metals from Metal-Mining Deposit (동전기법에 의한 광산퇴적토의 중금속 제거 특성)

  • Lee, Chang-Eun;Shin, Hyun-Moo
    • Journal of Environmental Science International
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    • v.12 no.2
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    • pp.227-236
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    • 2003
  • Electrokinetic remediation technique offers the opportunity to extract heavy metals from soils with high plasticity. The experiment demonstrated the applicability of electrokinetic remediation on metal-mining deposit and the decision of the enhancement method for four kinds of bench-scale studies. According to the sequential extraction of heavy metals in the "I" mining deposit, Pb and Cu were mostly associated with residual fraction and Zn and Cd were associated with water soluble and residual fraction. Therefore, removable fractions by electrokinetic technology was determined by the sum of the fraction of water soluble and exchangeable, which is Cu : 19.53%, Pb : 1.42%, Cd : 52.82%, Zn : 57.28%, respectively. When considering electrical potential, volume of effluent, soil pH, and eliminated rate of contaminant, results determined by sum of each weight were Citric aic+SDS (13) > 0.1N $HNO_3$ (10) > HAc (8) > DDW (4). Therefore, citric acid and SDS mixed solution was determined the best enhancing agent for the remediation of metal mining deposit.g deposit.

Density Composition and Feeding Guild of the Dominant Polychaetous Community in Shallow Muddy Bottom in Tomioka Bay, Amakusa, Japan

  • LEE Si-Wan;PAIK Eui-In
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.6
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    • pp.793-804
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    • 1995
  • Polychaetous community survey in Tomioka Bay was carried out 5 times seasonally from May 1991 to March 1992 by quantitative grab sampling (0.05m2) at 11 stations. Based on the granulometric composition and environmental factors, a homogeneous soft bottom was found in St.5-10. The species of the polychaete were classified into three feeding groups using the Fauchald and Jumars' feeding guild system. According to polychaetous community composition data, deposit feeders predominate in sandy silt area where the silt-clay content is $60-69.3\%.$ These deposit feeders were subdivided into surface deposit feeders and subsurface deposit feeders by their living position and mode. Also, suspension feeding group comes as the third dominant group. Seasonal changes of each feeding group were described in terms of numerical density and biomass. Feeding layer and types of dominant species (Lumbrineris longifolia: surface deposit feeder; Praxillella pacifica: subsurface deposit feeder; Chone duneri; suspension filter feeder, etc.) were examined in the intact sediment core samples. Also, longterm density change among the three dominant species during 10 years was disussed.

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Development of Deposit Process and Function Design for Web Archiving of Digital Resources (디지털 자원의 웹 아카이빙을 위한 납본 프로세스 개발 및 기능 설계)

  • Oh, Sang-Hoon;Choi, Young-Sun
    • Journal of the Korean Society for information Management
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    • v.25 no.4
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    • pp.5-23
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    • 2008
  • The National Library of Korea is administering a legal deposit system for the printedpublications. Whereas, OASIS(Online Archiving & Searching Internet Sources) has to design a system to collect, manage and preserve web sites and web resources for Web Archiving. The purpose of this study is to develop a digital deposit process for digital resources. As a result, this study defines the subjects and objects for digital deposits, and describes the definitions and the functions according to digital deposit steps. Also, this study designs the data flow diagram and proposes the function definitions on unit works and the structure for the flow of information.