• Title/Summary/Keyword: 입도 분석

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A Study of material analysis and its experimentation of metamorphosis and its utilities in Copper Alloy plates for contemporary metal craft (현대금속공예용 동합금판의 재료분석과 형질변환 실험 및 응용에 관한 연구)

  • Lim, Ock-Soo
    • Archives of design research
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    • v.17 no.4
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    • pp.241-250
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    • 2004
  • In this research, the copper alloy plates C2200, C5210, C7701, C8113 were selected to make datum and to identify further usage of metal craft experimentation. For its experimentation, the general welding and TIG welding methods were researched; for 2nd experimentation, the Reticulation and Electroforming skill's differences in color and temperature were researched. With these methods 3 different kinds of works are introduced for sample studies. For this research, Dr. Lee, Dong-Woo who works in Poongsan Metal Co, supported 4 kinds of copper alloy metals. Which are Commercial bronze (Cu-Zn), Deoxidiged Copper(Cu-Sn-P), Nickel Silver (Cu-Ni-Zn), and White Bronze (Cu-Ni); they were applied partly and wholly by the method of Laminatin, Reticulation, Fusing, and Electroforming skills. In case of C2200, the brass, the A. C. TIG welding method is better under 2mm slight plate; the D.C. TIG welding is better upper 2mm plate; and 250~300$^{\circ}C$ is recommended for remain heat treatment. In case of C5210, not having Hydrogen in high temperature return period, doesn't need Oxygen in high temperature and hardening in comparative high temperature neither, it is good for welding. It contains Sn 2-9% ad P 0.03-0.4% generally; and in accordance with the growth rate of Sn contain amount, the harden temperature boundary become broad. In case of cold moment after welding, they are recommended that higher speed TIG welding, smaller melting site and less than 200$^{\circ}C$ for pre-heating temperature. In case of C7701, the 10-20% Ni, 15-30% Zn are widely used.. If it is upper 30% Zn, it become (${\alpha}+{\beta}$) system and adhesive power rate become lower, and the productivity become lower in low temperature but the productivity become higher in high temperature. Nickel Silver's resistance of electricity is well; and the heatproof and incorrodibility is good, too. Lastly, in case of C8113, good at persistence in salty and grind; high in strength of high temperature. In case of white brass, contain 10-30% Nickel and hardened in high temperature and become single phrase. For these reason, the crystallization particles easily become large, if the resistance become higher small amount of Pb, P, S separation rate become higher.

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A Study on the Effect of On-Dock System in Container Terminals - Focusing on GwangYang Port - (컨테이너터미널에서 On-Dock 시스템 효과분석에 관한 연구 - 광양항을 중심으로 -)

  • Cha, Sang-Hyun;Noh, Chang-Kyun
    • Journal of Navigation and Port Research
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    • v.39 no.1
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    • pp.45-53
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    • 2015
  • These days Container Terminals are focusing on increasing the quantity of containers and shipping lines choose Terminals by referring to the key elements of a terminal to perform the overall operation the fastest such as the location of the terminal, discharging ability, keeping environment, and other elements related to shipping in general. Container terminal is able to offer On-Dock service has become an important factor for shipping lines to choose that terminal. In this paper, we propose an algorithm for On-Dock system work algorithm, the algorithm Empty container exports, Full Container algorithm and The aim of our study focus on both container's gate out time and search for the effective terminal operation which is using the general On-Dock system through several algorithm like container batch priority, gate in and out job priority and empty container yard equipment allocation rule based on the automatic allocation method and manual allocation scheme for container. Gathering these information, it gives the priority and yard location of gate-out containers to control. That is, by selecting an optimum algorithm container, container terminals Empty reduces the container taken out time, it is possible to minimize unnecessary re-handling of the yard container can be enhanced with respect to the efficiency of the equipment. Operations and operating results of the Non On-Dock and On-Dock system is operated by the out work operations (scenarios) forms that are operating in the real Gwangyang Container Terminal derived results. Gwangyang Container terminal and apply the On-Dock system, Non On-Dock can be taken out this time, about 5 minutes more quickly when applying the system. when managing export orders for berths where On-Dock service is needed, ball containers are allocated and for import cargoes, D/O is managed and after carryout, return management, container damage, cleaning, fixing and controlling services are supported hence the berth service can be strengthened and container terminal business can grow.

Adequacy of Medical Manpower and Medical Fee for Newborn Nursery Care (신생아실 의료인력의 적정성 및 신생아관리료의 타당성 분석)

  • Park, Jung-Han;Kim, Soo-Yong;Kam, Sin
    • Journal of Preventive Medicine and Public Health
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    • v.24 no.4 s.36
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    • pp.531-548
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    • 1991
  • To assess the adequacy of medical manpower and medical fee for the newborn nursery care, the author visited 20 out of 24 hospitals with the pediatric training program in Youngnam area between July 29 and August 14, 1991. Total number of newborn, both normal and sick, admission and discharge in 1-30 June 1991 was obtained from the logbook of nursery. Head nurse and staff pediatrician of the nursery were interviewed to get the current staffing for the nursery and their subjective opinion on the adequacy of nursery manpower and the difficulties in recruiting manpower. Average medical fee charged for the maternity and normal newborn nursery care was obtained from the division of self-audit of medical insurance claim of each hospital. Average minimum requirement of nursing care time for one normal newborn per day was 179.5 (${\pm}58.6$) minutes; 202.3(${\pm}50.7$) minutes for the university hospitals and 164.2(${\pm}60.5$) minutes for the general hospitals. The ratio of minimum requirement of nursing care time and available nursing time was 1.42 on the average. Taking the additional requirement of nursing care for the sick newborns into consideration, the ratio was 2.06. The numbers of R. N. and A. N. in the nurserys of study hospitals were 31%, and 17%, respectively, of the nursing manpower for the nursery recommended by the American Academy of Pediatrics. These findings indicate that the nursing manpower in newborn nursery is in severe shortage. Ninety percent of the head nurses and 85% of the staff pediatrician stated that the newborn nursery is short of R.N. and 75% of them said that the nurse's aide is also short. Major reason for not recruiting R.N. was the financial constraint of hospital. For the recruitment of nurse's aide, short supply was the second most important reason next to the financial constraint. However, limit of quarter in T.O. was the mar reason for the national university hospitals. Average total medical fee for the maternity and newborn nursery cares of a normal vaginal delivery who stayed two nights and three days at hospital was 219,430won. Out of the total medical fee, 20,323won(9.3%) was for the newborn nursery care. In case of C-section delivery who stayed six nights and seven days, total medical fee was 732,578won and out of the total fee 76,937won (12.0%) was for the newborn care. Cost for a newborn care per day by cost accounting was 16,141won for the tertiary care hospitals and 14,576won for the all other hopitals. The ratio of cost and the fee schedule of the medical insurance for a newborn care per day was 5.0 for the tertiary care hospitals and 4.9 for the all other hospitals. Considering the current wage level of the medical personnel, capital investment for the hospital facilities and equipments, and the cost for hospital maintenance, it is hard to expect adequate quality care in the newborn nursery under the current medical insurance fee schedule.

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Evaluation of the Temperature Drop Effect and the Rutting Resistance of Moisture Retaining-Porous Asphalt Pavement Using Accelerated Pavement Testing (포장가속시험을 이용한 보수형 배수성 포장의 온도저감 효과 및 소성변형 저항특성 연구)

  • Kwak, Byoung-Seok;Suh, Young-Chan;Song, Chul-Young;Kim, Ju-Won
    • International Journal of Highway Engineering
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    • v.11 no.3
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    • pp.97-109
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    • 2009
  • One of the main causes of asphalt rutting is high temperature of the pavement. Nevertheless, there has been few research on lowering the pavement temperature for reducing rutting. This study investigated the performance characteristics of moisture-retaining porous asphalt pavement, which is known to have a temperature reducing effect. The purpose of this study is to quantify the temperature reducing effect of moisture-retaining porous asphalt pavement and its effect of reducing rutting through Accelerated Pavement Testing(APT). Additionally, the possibility of reducing the thickness of the pavement in comparison to general dense grade pavement by analyzing structural layer coefficient of moisture retaining pavement. A total of three test sections consisting of two moisture-retaining porous asphalt pavement sections and one general dense-grade porous asphalt pavement section were constructed for this study. Heating and spraying of water were carried out in a regular cycle. The loading condition was 8.2 ton of wheel load, the tire pressure of $7.03kgf/cm^2$, and the contact area of $610cm^2$. The result of this experiment revealed that the temperature reducing effect of the pavement was about $6.6{\sim}7.9^{\circ}C$(average of $7.4^{\circ}C$) for the middle layer and $7.9{\sim}9.8^{\circ}C$(average of $8.8^{\circ}C$) for surface course, resulting in a rutting reduction of 26% at the pavement surface. Additionally, the structural layer coefficient of moisture retaining pavement measured from a laboratory test was 0.173, about 1.2 times that of general dense grade pavement. The general dense-grade porous asphalt pavement test section exhibited rutting at all layers of surface course, middle layer, and base layer, while the test sections of moisture-retaining porous asphalt pavement manifested rutting mostly at surface course only.

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Particle-size Effect of Silicate Fertilizer on Its Solubility and Mobility in Soil (토양(土壤)에 처리한 광재규산질비료의 입도별(粒度別) 용해도(溶解度) 및 이동성(移動性))

  • Yoo, Sun-Ho;Park, Lee-Dal
    • Korean Journal of Soil Science and Fertilizer
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    • v.13 no.2
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    • pp.57-63
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    • 1980
  • The effect of particle size of silicate fertilizer, crushed slag from the steel industry, on the behavior of silicate in soil was investigated through laboratory experiments. The silicate fertilizer was sieved to obtain three fractions of particles, coarser than 10 mesh 20-35 mesh, and finer than 100 mesh. Silicate concentration of the extract obtained by shaking 20 mg of particles, coarser than 10 mesh, 20-35 mesh, and finer than 100 mesh, in 50 ml of distilled water for 4 hours was 0.3, 1.0, and 3.2 ppm respectively. As shaking the mixture of the silicate fertilizer and soil proceeded, silicate concentration of the extract increased, and this increase after 4 hour shaking was attributed mainly to dissolution of soil silicate. When the mixture of soil and the silicate fertilizer was incubated under submerged condition, silicate concentration of the solution decreased for the first 2-4 weeks, thereafter increased with incubation time. During this incubation period, silicate concentration of the solution changed inversely with pH of the solution. After 6-10 weeks, however, both silicate concentration and pH of the solution increased with incubation time. Silicate concentration of the effluent from the 14.5 cm soil column of which top 4.5 cm was packed with the mixture of 30 g of soil and 30 mg of the silicate fertilizer reached maximum at 0.94 pore volumes for the particles of 20-35 mesh and 1.03 pore volumes for the particles finer than 100 mesh, whereas the effluent concentration reached maximum at 0.88 pore volumes for the soil column without the silicate fertilizer treatment. Soil analysis made after water percolation revealed that 1.5 pore volumes of water could leach down large amount of the water soluble silicate but not the sodium acetate extractable silicate, from top 3-6 cm soil layer.

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Properties of Pepper growth and Yield, Cost Down with No-Tillage Organic Cultivation in Vinyl Greenhouse (시설고추 무경운 유기 재배의 생육 및 수량 특성과 생산비 절감효과)

  • Yang, Seung-Koo;Seo, Youn-Won;Son, Jang-Hwan;Park, Jong-Dae;Choi, Kyung-Ju;Jung, Woo-Jin
    • Korean Journal of Organic Agriculture
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    • v.20 no.3
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    • pp.411-422
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    • 2012
  • To investigate the possibility of sustainable agriculture in no-tillage pepper this study was carried out in vinyl greenhouse with organic cultivation having no pesticide certification. 1. Growth and yield in pepper cultivation General growth in pepper was suppressed with decreasing hill spacing, primary branch length, and stem width. Fruit diameter and fruit weight in no-tillage increased significantly, and yield of pepper increased by 10% compared with conventional tillage. From results organic cultivation in no-tillage improved a quality of pepper compared with conventional tillage. 2. Production cost of conventional tillage and no-tillage Production cost of conventional tillage and no-tillage was not different in seed cost, inorganic fertilizer cost, pesticide cost, repair cost, light agricultural tool cost, agriculture facilities depreciation cost and so on. Intermediary goods cost in no-tillage was decreased by 11% for organic fertilizer cost, light and heat expenses and power rate, heavy agricultural tool cost, and repairing expenses compare with conventional tillage. Employment effort cost and work effort cost were decreased, and farm income and farm income rate were increased by 11% and 5%, respectively, in no-tillage. In this work, yield and gross income were increased by 10% and 25%, respectively, in no-tillage. Therefore material cost, intermediary goods cost, working expensive, farm income, and income rate were increased by 34%, 3%, 2%, 52% and 22%, respectively.

Spatial Distribution of Macrozoobenthos Along the Salinity Gradient and Sedimentary Environment in the Watancheon Estuary, Beobseongpo, Southwest Coast of Korea (법성포 와탄천 하구역의 염분과 퇴적환경에 따른 대형저서동물의 공간분포)

  • Hong, Jae-Sang;Lim, Hyun-Sig
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.7 no.1
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    • pp.8-19
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    • 2002
  • Spatial distribution pattern of macrozoobenthos was studied along the salinity gradient and sedimentary environment in the Watancheon estuary, Beobseongpo, southwest coast of Korea. Ten stations were set from the mouth towards the head of estuary. Three replicate sediment samples were taken using a van Veen grab (surface area $0.1m^{2}$) at each station between June 1998 and January 1999. A total of 114 species were collected during the study period and they are composed of 44 species of polychaetes (39%), 34 of crustaceans (30%), 24 of molluscs (21%) and 12 of miscellaneous. The former two taxa together accounted for 69% in the total number of species. The mean density was 3,053 ind./m$^{2}$, comprising 2,536 ind./m$^{2}$ from polychaetes (83%) and 439 ind./m$^{2}$, crustaceans (14%). Moreover, the mean biomass was 58.23 gwwt./m$^{2}$, consisting of 29.56 gwwt./m$^{2}$ from polychaetes (51%), 23.38 gwwt./m$^{2}$, molluscs (40%). A spionid polychaete Minuspio japonica, two corophiid amphipods Grandidierella japonica and Corophium sinense, a bivalve Potamocorbula amurensis were major dominants at the head of estuary where the salinity was relatively lower compared with contiguous sites. The distributions of M. japonica and G. japonica were significantly related to the salinity and sediment environment, respectively, whereas C. sinense and P, amurensis showed no significance. The nereid polychaete, Hediste japonica, also predominated at the head of the estuary where bottom salinity was relatively low. Species diversity was high at the mouth area whereas low diversity and few species number were seen at the stations in the head of the estuary, influenced by freshwater and sandy sediment. Based on the cluster analysis, the macrobenthic community was classified into four station groups from head (station group A) toward mouth (group D) in the study area. The number of species and abundance between station group B and C were significantly different. And the abundance of between two neighboring station groups (station group A and B, B and C, C and D) was also different. These results suggested that the spatial distribution pattern of macrobenthos in this estuary seemed mainly related to gradients in bottom salinity and sediment grain size among environmental factors.

Estimation of forest Site Productivity by Regional Environment and Forest Soil Factors (권역별 입지$\cdot$토양 환경 요인에 의한 임지생산력 추정)

  • Won Hyong-kyu;Jeong Jin-Hyun;Koo Kyo-Sang;Song Myung Hee;Shin Man Yong
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.7 no.2
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    • pp.132-140
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    • 2005
  • This study was conducted to develop regional site index equations for main tree species in Gangwon, Gyunggi-Chungcheong, Gyungsang, and Jeolla area of Korea, using environmental and soil factors obtained from a digital forest site map. Using the large data set obtained from the digital forest map, a total of 28 environmental and soil factors were regressed on site index by tree species for developing the best site index equations for each of the regions. The selected main tree species were Larix 1eptolepis, Pinus koraiensis, Pinus densiflora, Pinus thunbergii, and Quercus acutissima. Finally, four to five environmental and soil factors by species were chosen as independent variables in defining the best regional site index equations with the highest coefficients of determination $(R^2)$. For those site index equations, three evaluation statistics such as mean difference, standard deviation of difference and standard error of difference were applied to the data sets independently collected from fields within the region. According to the evaluation statistics, it was found that the regional site index equations by species developed in this study conformed well to the independent data set, having relatively low bias and variation. It was concluded that the regional site index equations by species had sufficient capability for the estimation of site productivity.

Studies on the Combining Ability for Silage Yield and Major Agronomic Characters of Corn (사료용 옥수수 선발을 위한 수량 및 주요형질의 조합능력 분석)

  • 이명훈
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.32 no.2
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    • pp.201-207
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    • 1987
  • This experiment was conducted to identify the superior corn hybrids for silage production and to determine the combining ability of their parental inbred lines. A 7-entry diallel cross was evaluated for grain and stover yields, and agronomic characters under 3 different seasons. Hybrids Hi34 x Tx601, Hi26 x Hi34, and Hi29 x Hi34 showed high total dry matter yields. In general, late maturing hybrids had higher grain and silage yields than early maturing hybrids. Leaf area index was correlated with grain and stover yields. Rust rating was negatively correlated with yields and all characters, indicating that rust (Puccinia sorghi) was one of the major factors affecting yields. Diallel analysis showed that inbred Hi34 which was late in maturity and resistant to rust was the best combiner for both grain and silage yields. General combining ability (GCA) and specific com-bining ability (SCA) effects for yields and other characters were significant, suggesting that both additive and non-additive gene effects are involved for those characters. Ratio of GCA/SCA mean squares showed that GCA effects were more important than SCA effects for yields and other characters. GCA x season and SCA x season interactions were significant for grain and stover yields, revealing that gene effects were not stable for those yields under dissimilar environments.

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Eutrophication in the Upper Regions of Brackish Lake Sihwa with a Limited Water Exchange (물 교환이 제한적인 시화호 상류 기수역의 부영양화)

  • Choi, Kwnag-Soon;Kim, Sea-Won;Kim, Dong-Sup;Heo, Woo-Myoung;Lee, Yun-Kyoung;Hwang, In-Seo;Lee, Han-Jin
    • Korean Journal of Ecology and Environment
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    • v.41 no.2
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    • pp.216-227
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    • 2008
  • To understand eutrophication in the upper regions of brackish Lake Sihwa with a limited water exchange, temporal and spatial distributions of pollutants in water and sediment were investigated from March to October in 2005 and 2006. Also, pollution levels of water and sediment were estimated by trophic state index (TSI) and sediment quality guideline (SQG). Total nitrogen (TN), total phosphorus (TP), organic matter (COD), and chlorophyll $\alpha$ (Chl-$\alpha$) concentrations in the surface waters were largely varied temporally and spatially, and the variations were highest in the middle areas where strong halocline was formed. Chl-$\alpha$ concentrations in the middle area were very high in April (>$900\;{\mu}g\;L^{-1}$) when algal blooms (red tides) occurred. The relationships between TN and Chl-$\alpha$ (r=0.31), and TP and Chl-$\alpha$ (r=0.65) indicated that the algal growth was primarily affected by phosphorus rather than nitrogen. The distribution of COD was similar to that of Chl-$\alpha$, indicating that the autochthonous organic matters may be a more important carbon source, especially in the middle areas. The brackish water regions were classified as eutrophic or hypertrophic based on their TSI values ($69{\sim}76$). In addition, the content of nutrients (especially TP) in surface sediments were classified as severe polluted state, except the upper areas. Major causes of the eutrophication observed were probably due to high nutrients loading from watersheds, the phosphorus release from anaerobic sediment, and long retention time by the limited water exchange through the sluice gates.