• Title/Summary/Keyword: 필수원소

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A Design of a Network Module supporting Primitive Messaging Operations for MOM (MOM의 Primitive Messaging Operation을 지원하는 네트워크 모듈 설계)

  • Kang, Tae-Gun;Sohn, Kang-Min;Ham, Ho-Sang
    • Proceedings of the Korea Information Processing Society Conference
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    • 2003.11a
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    • pp.115-118
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    • 2003
  • 최근 MOM 기술은 비즈니스 로직을 수행하는 애플리케이션 서버의 필수적인 구성요소로서 자리잡고 있으며, 보통 수백에서 수천의 클라이언트 요청을 처리할 수 있는 능력을 제공한다. MOM 은 이러한 대용량의 클라이언트 요청을 효과적으로 처리하기 위해서 효율적이고 확장성있는(스케일러블) 네트워크 모듈이 필요하며, 다양한 네트워크 프로토콜을 지원해야 한다. MOM이 기본적으로 지원하는 메시징 기능은 PTP(Point-To-Point)와 publish/subscribe 메시징 도메인으로 나뉘는데 이 논문에서는 두 가지 메시징 도메인과 그룹통신 메시징 서비스 기능을 동시에 지원하는 MoIM-Message 시스템의 하부 통신 모듈의 설계에 대해 기술한다. PTP와 publish/subscribe 메시징을 지원하기 위해 세가지 프리미티브 메시징 오퍼레이션인 "synchronous send", "synchronous receive", "asynchronous receive"를 정의하였으며 하부 통신 모듈 역할을 하는 메시지 트랜스포트 관리 계층내의 트랜스포트 관리자 내에 구현되었다. 트랜스포트 관리자는 다양한 트랜스포트 프로토콜을 적용할 수 있도록 하기 위해 트랜스포트 어댑터로 설계되었으며, 대량의 통신 요청을 효과적으로 처리하기 위해 "polling with multiple service thread model" 기법을 적용하여 구현되었다. 또한, 모바일 클라이언트 환경을 지원하기 위해 클라이언트 측 통신 모듈을 IPaq PDA 상에 포팅하였다. 본 논문에서 제안하는 세 가지 프리미티브 메시징 오퍼레이션을 제공하는 통신 모듈은 MOM이 기본적으로 지원해야 할 메시징 도메인과 대용량의 클라이언트 요청을 효율적으로 처리할 수 있는 구조를 가진다.es}8$ 모드를 모두 사용한 경우와 $8{\times}8$ 단일모드를 사용한 경우보다 계산 시간이 감소하였음을 확인하였다.행중인 MoIM-Messge서버의 네트워크 모듈로 다중 쓰레드 소켓폴링 모델을 적용하였다.n rate compared with conventional face recognition algorithms. 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.>10)의 $[^{18}F]F_2$를 얻었다. 결론: $^{18}O(p,n)^{18}F$ 핵반응을 이용하여 친전자성 방사성동위원소 $[^{18}F]F_2$를 생산하였다. 표적 챔버는 알루미늄으로 제작하였으며 본 연구에서 연구된 $[^{18}F]F_2$가스는 친핵성 치환반응으로 방사성동위원소를 도입하기 어려운 다양한 방사성의 약품개발에 유용하게 이용될 수 있을 것이다.었으나 움직임 보정 후 영상을 이용하여 비교한 경우, 결합능 변화가 선조체 영역에서 국한되어 나타나며 그 유의성이 움직임 보정 전에 비하여 낮음을 알 수 있었다. 결론: 뇌활성화 과제 수행시에 동반되는 피험자의 머리 움직임에 의하여 도파민 유리가 과대평가되었으며 이는 이 연구에서 제안한 영상정합을 이용한 움직임 보정기법에

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Monitoring of Heavy Metals in Agricultural Soils from Consecutive Applications of Commercial Liquid Pig Manure (돈분액비 연용 농경지 중 중금속 함량 모니터링)

  • Go, Woo-Ri;Kim, Ji-Young;Yoo, Ji-Hyock;Lee, Ji-Ho;Kunhikrishnan, Anitha;Lee, Jeong-Mi;Kim, Kye-Hoon;Kim, Doo-Ho;Kim, Won-Il
    • Korean Journal of Environmental Agriculture
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    • v.31 no.3
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    • pp.217-223
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    • 2012
  • BACKGROUND: Increase of heavy metals in agricultural ecosystem has become a social issue nationwide as it is related to public health. This study was performed to find out the status and long-term trends with consecutive application with the commercial liquid pig manure in the agricultural fields. METHODS AND RESULTS: Heavy metals including arsenic, cadmium, copper, lead, nickel, and zinc were analyzed in the 41 samples of paddy fields and 54 samples of upland fields consecutively applied with commercial liquid pig manure for 0 to 16 years. Heavy metal accumulation were not increased statistically at the both paddy and upland fields as the consecutive application year of commercial liquid pig manure were increased. However, some of surveyed upland soils exceeded the criteria of cadmium, copper, and zinc designated by the Soil Environmental Conservation Act in Korea. CONCLUSION: Therefore, analysis of heavy metals, specially copper and zinc, in agricultural fields is absolutely necessary before liquid pig manure application to the fields. In addition, heavy metal accumulation in agricultural fields following to the long-term application of liquid pig manure will be monitored periodically considering with bioavailability of copper and zinc to the crops as an essential nutrients.

Trends of Thermochemical Technology for the Recovery of Phosphorus from Sewage Sludge Ash (열화학적 방법에 의한 하수 슬러지 소각재에서의 인 회수 기술 동향)

  • Jeon, Seulki;Shin, Hyuna;Kim, Dong-Jin
    • Clean Technology
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    • v.24 no.2
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    • pp.87-98
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    • 2018
  • Phosphorus (P) is an essential and irreplaceable element for all living organisms, and it is widely used as a fertilizer. Unfortunately, it is estimated that phosphate reservoir is depleted within about 100 years. Sewage sludge ash (SSA) is an alternative resource for P recovery because of its high P content. However, SSA cannot be directly used as a fertilizer due to heavy metals in it and low P bioavailability. Thermochemical treatment with Cl donor is known to reduce heavy metal contents and increase P bioavailability of SSA. Literature review on thermochemical technologies of SSA for the reduction of heavy metals and bioavailability enhancement has been carried out to estimate the status of current P recovery technology and to develop strategic future research plan for P recovery. The review showed that $CaCl_2$ and $MgCl_2$ were the most effective Cl donors and reaction temperature (< $1000^{\circ}C$) was the critical operation condition for the reduction. The removal efficiency depends on the species of heavy metals. Thermochemical technology of SSA for P recovery showed the possibility of commercial application in the near future to overcome the coming crisis of human sustainability by P depletion, but it needs cost effectiveness and more ecofriendly process to reduce energy consumption.

Determination of Optimal Conditions by Response Surface Methodology and Quality Characteristics of Water Extracts of Phellinus linteus (반응표면분석을 이용한 상황버섯 열수추출액의 최적 추출조건과 품질 특성)

  • Youn, Sun-Joo;Cho, Jun-Gu;Kwoen, Dae-Jun;Choi, Ung-Kyu;Kang, Sun-Chul
    • Applied Biological Chemistry
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    • v.49 no.3
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    • pp.215-220
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    • 2006
  • Response surface methodology was implemented to determine an optimal extraction condition in Phellinus linteus water extract. Extraction was performed on 10 experimental conditions including independent variables such as extraction time $(1{\sim}5\;hrs)$ and water volume over sample (sample : $H_2O$ = 1 : $40{\sim}200$, W/V), color browning, reducing and total sugar, that were based on the significant levels of 10% of central composition design. Color browning, reducing and total sugar contents were found to be more affected when the water volume was increased rather than extraction time. Maximum extraction condition was acquired at extraction time of $3.0{\sim}4.5\;hrs$ and water volume of $40{\sim}58.2\;ml$. Being extracted at the optimal extraction condition two of the free sugars, sucrose (0.126%) and glucose (0.012%), were detected. Total content of the free amino acids was found to be $503.26\;{\mu}g%$. Among them, essential amino acid contents were revealed as 5.4%. One major peak from gel permeation chromatography contained polysaccharide(s) with the molecular weights of 10 KDa.

Crystallinity and Chemical Reactivity of Bimessite(δ-MnO2) Influenced by Iron (철에 의한 버네사이트의 결정도 및 화학적 활성의 변화)

  • Kim, Jae-Gon
    • Korean Journal of Soil Science and Fertilizer
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    • v.32 no.4
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    • pp.327-332
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    • 1999
  • Manganese (Mn) oxides in soils have been a research subject since they react with nutrients and contaminants and Mn itself is an essential element for plant growth. Birnessite was synthesized in the presence of iron (Fe) in the precipitating solution. Influence of Fe, one of common elements in soils, on crytallinity, morphology, and chemical reactivity of birnessite was examined using X-ray diffraction (XRD), electron microscope, canon exchange capacity (CEC), and chromium (Cr) oxidation capacity. With increasing Fe concentration in the precipitating solution, crystallinity and crystal size decreased. Hexagonal plates of the birnessites formed at low Fe concentration were dominant and replaced more and more by aggregate of small particles with increasing the Fe concentration. There is no significant change in CEC with changing the Fe concentration. Chromium oxidation capacity of the birnessite increased with increasing the Fe concentration. Iron in the precipitating solution poisoned crystal growth by adsorption on the surface and increased nucleation. Since Fe is a common constituent under pedogenic environment and Fe and Mn oxides often coexist in Mn oxide nodules, the birnessite with small particle, low crystallinity, and high chemical reactivity is the form which is more likely to be formed in soils. The high CEC ($140cmol_ckg^{-1}$) and oxidation capacity of birnessite indicate that birnessite can be used in environment and agriculture.

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Radioanalytical and Spectroscopic Characterizations of Hydroxo- and Oxalato-Am(III) Complexes (방사분석과 분광학을 이용한 Am(III) 가수분해와 옥살레이트 착물 화학종 연구)

  • Kim, Hee-Kyung;Cho, Hye-Ryun;Jung, Euo Chang;Cha, Wansik
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.16 no.4
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    • pp.397-410
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    • 2018
  • When considering the long-term safety assessment of spent-nuclear fuel management, americium is one of the most radio-toxic actinides. Although spectroscopic methods are widely used for the study of actinide chemistry, application of those methods to americium chemistry has been limited. Herein, we purified $^{241}Am$ to obtain a highly pure stock solution required for spectroscopic studies. Quantitative and qualitative analyses of purified $^{241}Am$ were carried out using liquid scintillation counting, and gamma and alpha radiation spectrometry. Highly sensitive absorption spectrometry coupled with a liquid waveguide capillary cell and time-resolved laser fluorescence spectroscopy were employed for the study of Am(III) hydrolysis and oxalate (Ox) complexation. $Am^{3+}$ ions under acidic conditions exhibit maximum absorbance at 503 nm, with a molar absorption coefficient of $424{\pm}8cm^{-1}{\cdot}M^{-1}$. $Am(OH)_3(s)$ colloidal particles formed under near neutral pH conditions were identified by monitoring the absorbance at around 506-507 nm. The formation of ${Am(Ox)_3}^{3-}$ was detected by red-shifts of the absorption and luminescence spectra of 4 and 5 nm, respectively. In addition, considerable enhancements of the luminescence intensities were observed. The luminescence lifetime of ${Am(Ox)_3}^{3-}$ increased from 23 to 56 ns, which indicates that approximately six water molecules are replaced by carboxylate ligands in the inner-sphere of the Am(III). These results suggest that ${Am(Ox)_3}^{3-}$ is formed through the bidentate coordination of the oxalate ligands.

Chemical Composition and Antioxidant Activity of Korean Buckwheat (Fagopyrum esculentum) Pollen Grain Collected by Honey Bee, Apis mellifera (메밀화분의 성분 특성 및 항산화 활성)

  • Hong, In-Pyo;Woo, Soon-Ok;Han, Sang-Mi;Lee, Mi-Kyoung
    • Journal of Apiculture
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    • v.32 no.3
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    • pp.261-268
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    • 2017
  • We evaluated the nutritional composition including proximate, amino acid, vitamin, minerals, and the antioxidant activity of buckwheat (Fagopyrum esculentum) pollen grains collected by Apis mellifera bees, to be used as a species of forage plant with Quercus acutissima (acorn) and Actinidia arguta pollen grains. The content of crude protein and fat were found 14.43% and 5.67%, respectively. Eighteen amino acids from buckwheat pollen were found, including 8 essential amino acids. The predominant amino acids were glutamic acid, aspartic acid and lysine, accounting for about 42.7% of total free amino acids. The concentration of vitamin C was the highest value of 13.7 mg/100g, followed by $B_3$ (niacin) and $B_1$ among the detected vitamins. The predominant minerals were potassium (1197.95mg/100g), followed by phosphorus (962.77mg/100g) and magnesium (535.42mg/100g), whereas copper, zinc and manganese were detected as minor elements. Antioxidant activity and total phenolic content accounted for 8.1% at $500{\mu}g/ml$ extract and $2.25{\mu}g/mg$, respectively.

PEO/PPC based Composite Solid Electrolyte for Room Temperature Operable All Solid-State Batteries (상온에서 작동되는 전고체전지 용 PEO/PPC 기반의 복합 고체 전해질)

  • Shin, Sohyeon;Kim, Sunghoon;Cho, Younghyun;Ahn, Wook
    • Journal of the Korean Electrochemical Society
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    • v.25 no.3
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    • pp.105-112
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    • 2022
  • For the commercialization of all-solid-state batteries, it is essential to develop a solid electrolyte that can be operable at room temperature, and it is necessary to manufacture all-solid-state batteries by adopting materials with high ionic conductivity. Therefore, in order to increase the ionic conductivity of the existing oxide-based solid, Li7La3Zr2O12 (LLZO) doped with heterogeneous elements was used as a filler material (Al and Nb-LLZO). An electrolyte with garnet-type inorganic filler doped was prepared. The binary metal element and the polymer mixture of poly(ethylene oxide)/poly(propylene carbonate) (PEO/PPC) (1:1) are uniformly manufactured at a ratio of 1:2.4, The electrochemical performance was tested at room temperature and 60 ℃ to verify room temperature operability of the all-solid-state battery. The prepared composite electrolyte shows improved ionic conductivity derived from co-doping of the binary elements, and the PPC helps to improve the ionic conductivity, thereby increasing the capacity of all-solid-state batteries at room temperature as well as 60 ℃. It was confirmed that the capacity retention rate was improved.

A Study on the Prediction of Nugget Diameter of Resistance Spot Welded Part of 1.2GPa Ultra High Strength TRIP Steel for Vehicle (차체용 1.2GPa급 초고장력 TRIP강판의 저항 점 용접부 너겟 지름 예측에 관한 연구)

  • Shin, Seok-Woo;Lee, Jong-Hun;Park, Sang-Heup
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.3
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    • pp.52-60
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    • 2018
  • In the automobile industry, in order to increase the fuel efficiency and conform to the safety regulations, it is necessary to make the vehicles as light as possible. Therefore, it is crucial to manufacture dual phase steels, complex phases steels, MS steels, TRIP steels, and TWIP from high strength steels with a tensile strength of 700Mpa or more. In order to apply ultra-high tensile strength steel to the body, the welding process is essential. Resistance spot welding, which is advantageous in terms of its cost, is used in more than 80% of cases in body welding. It is generally accepted that ultra-high tensile strength steel has poor weldability, because its alloy element content is increased to improve its strength. In the case of the resistance spot welding of ultra-high tensile steel, it has been reported that the proper welding condition area is reduced and interfacial fracture and partial interfacial fracture occur in the weld zone. Therefore, research into the welding quality judgment that can predict the defect and quality in real time is being actively conducted. In this study, the dynamic resistance of the weld was monitored using the secondary circuit process variables detected during resistance spot welding, and the factors necessary for the determination of the welding quality were extracted from the dynamic resistance pattern. The correlations between the extracted factors and the weld quality were analyzed and a regression analysis was carried out using highly correlated pendulums. Based on this research, a regression model that can be applied to the field was proposed.

The Dissolution Characteristics of Metal Compounds in Soil Application Experiment using Sewage Treatment Sludge mixed with Oyster shells (하수슬러지 및 굴껍질의 토지주입시 금속성분의 용출특성에 관한 연구)

  • Kim, Chul;Moon, Jong-Ik;Shin, Nam-Cheol;Ha, Sang-An;Sung, Nak-Chang;Huh, Mock
    • Journal of the Korea Organic Resources Recycling Association
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    • v.9 no.2
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    • pp.71-76
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    • 2001
  • Recently, sludge disposal becomes one of the most serious environmental problems. Because the landfilling and ocean dumping of sludge materials will be prohibited in the near future, the proper treatment?disposal methods should be investigated. Also, oyster shells, piled at the coast, cause adverse effects in coastal fishery, public water surface, natural landscape, public health and so on. Thus, the purpose of this study is to evaluate the dissolution characteristic of metal compounds during soil application experiment using sewage treatment sludge mixed with oyster shells. The dissolution experiment conducted 100days under artificial rainfall and farming soil, mixed with sewage treatment sludge and oyster shells, was put into the pots(approx. 0.5L). The results from dissolution experiment as follows. 1. K, Na was $5{\sim}20mg/{\ell}$, and Ca was less than $90mg/{\ell}$. 2. Heavy metals such as Cd, Cu, As, Pb, Cr, Hg are dissoluted far less than the soil pollution guideline. The application of sewage sludge mixed with oyster shells increases pH(soil acidity)and buffer capacity(CEC) of farming soil, and heavy metals are thought to be attached to soil as insoluble forms.

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