• Title/Summary/Keyword: 석희석

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The Effects of KM Performances' Antecedents on an Eemployee's Absorptive Capacity (지식경영 성과 선행 요인이 조직원 흡수 역량에 미치는 영향)

  • Kim, Byoung-Soo;Hau, Yong-Sauk;Lee, Hee-Seok
    • Information Systems Review
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    • v.12 no.1
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    • pp.59-79
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    • 2010
  • According to resource based view, knowledge is regarded as a salient factor to improve an organization's efficiency in the current fast-changing business environment. Knowledge management (KM) may encourage employees to share and exchange knowledge in the organization in order to improve and sustain a competitive advantage over other companies. The proposed research model examines the impacts of KM performances' antecedents on an employee's absorptive capacity. This study identifies KM performances as employee's satisfaction about KM and shared knowledge quality. This study considers KM performances as the major determinants that enhance his/her absorptive capacity. This study also investigates the key antecedents of KM performances. The research model posits extrinsic reward, intrinsic reward, and relational reward as the KM performances' antecedents. Furthermore, this study examines the difference of the antecedents' effects in terms of firm's type. The proposed research model was tested by using survey data collected from 1,103 employees of 2 public enterprises and 907 employees of 5 private enterprises. The findings of this study showed that employee's satisfaction about KM and shared knowledge quality play a significant role in enhancing employee' absorptive capacity. Extrinsic reward only significantly influences employee's satisfaction about KM, whereas both intrinsic and relational rewards serve as the salient antecedents of improving both KM performances. The results also shed light on the moderating role of firm's type. Theoretical and practical implications of this study are discussed.

A Study on Analysis of electrolyzed water properties with pH changes (pH 변화에 따른 전리수 분석에 관한 연구)

  • Kim, Baekma;Kim, Minjung;Kim, Wohyuk;Kim, Bongsuk;Ryoo, Kunkul
    • Clean Technology
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    • v.10 no.1
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    • pp.47-51
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    • 2004
  • 현재 반도체 공정에서 사용되는 세정기술은 대부분이 1970년대 개발된 RCA 세정법인 과산화수소를 근간으로 하는 습식 세정으로, 표면의 입자를 제거하기 위한 SC-1 세정액은 강력한 산화제인 과산화수소에 의한 표면과 입자의 산화와 암모니아에 의한 표면의 에칭이 동시에 일어나 입자를 표면으로부터 분리시킨다. 금속 불순물을 제거하기 위한 SC-2 세정액은 염산과 과산화수소 혼합액을 사용하며 금속 불순물을 용해시켜 알칼리나 금속 이온을 형성하거나 용해 가능한 화합물을 형성시켜 제거한다. 또한 황산과 과산화수소를 혼합한 Piranha 세정액은 효과적인 유기물 제거제로서 웨이퍼에 오염된 유기물을 용해 가능한 화합물로 만들거나 과산화수소에 의해 형성되는 산화막내에 오염물을 포함시켜 불산 용액으로 산화막을 제거할 때 함께 제거된다. 최근 금속과 산화막을 동시에 제거하기 위해 희석시킨 불산에 과산화수소를 첨가한 세정공정이 사용되고 있으며 불산에 의해 표면의 산화막이 제거될 때 산화막내에 포함된 금속 불순물을 동시에 제거시킬 수 있다. 그러나 이와 같이 습식세정액 내에 공통적으로 포함되어 있는 과산화수소의 분해는 그만큼 가속화되어 사용되는 화학 약품의 양이 그만큼 증가하게 되고 조작하기 어려운 단점도 있다. 이를 해결하기 위해 환경친화적인 관점으로 화학약품의 사용을 최소화하는 등 RCA세정을 보완하는 연구가 계속 진행되고 있다. 본 연구에서는 RCA세정법을 환경적으로 대체할 수 있는 세정에 사용되는 전리수의 pH변화에 따른 전리수 분석을 하였다. 전리수의 제조를 위하여 전해질로는 NH4CI (HCI:H2O:NH4OH=1:1:1)를 사용하였다. pH 11 이상, ORP -700mV~-850mV인 환원수와 pH 3 이하, ORP 1000mV~1200mV인 산화수를 제조하였으며, 초순수를 첨가하여 pH 7.2와 ORP 351.1mV상태까지 조절하였다. 이렇게 만들어진 산화수와 환원수를 시간 변화와 pH 변화에 따라 Clean Room 안에서 FT-IR과 접촉각 측정기로 실험하였다. FT-IR분석에서 산화수는 pH가 높아질수록, 환원수는 낮아질수록 흡수율이 낮아졌다. 접촉각 실험에서는 산화수의 pH가 높아질수록 환원수의 pH가 낮아질수록 접촉각이 커짐을 확인하였다. 결론적으로 전리수를 이용하여 세정을 하면, 접촉성을 조절할 수 있어 반도체 세정을 가능하게 할 수 있으며, 환경친화적인 결과를 도출할 것으로 전망된다.

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Synthesis of I-125 Labelled Compound of Taxol Analogue for Radioimmunoassay (Taxol의 방사면역측정을 위한 I-125 표지화합물 합성)

  • 오옥두;금준섭;이양호;박용석;편웅범;최창운
    • Biomedical Science Letters
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    • v.3 no.2
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    • pp.125-130
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    • 1997
  • Taxol, an anticancer drug that has diterpenoid conformation, has been used as an effective chemotherapeutical agent in the treatment of breast and ovarian cancers. Because of its toxicity like other anticancer drugs, monitoring the taxol level in serum is important procedure during cancer therapy. The various monitoring methods using HPLC, ELISA, and RIA have been adopted, and RIA technique is known to be superior than other methods in trems of sensitivity and convenience. In this study, in order to develope taxol RIA system using $^{125}$I labelled antigen, first of all we synthesized taxol derivatives. 2'-hemisuccinyltaxol was obtained with about 80% yield by esterification of taxol at C-2' hydroxyl group on C-13 carbon with succinic anhydride. [$^{125}$I]iodotyramine was prepared with 58% labelling yield by radioiodination of tyramine and purified by gel chromatography. 2'-[$^{125}$I]iodotyramine-hemisuninyltaxol, $^{125}$I labelled antigen for taxol RIA, was synthesized with 96% yield from conjugation of 2'-hemisuccinyltaxol and [$^{125}$I]iodotyramine. Anti-taxol serum was produced from the rabbit immunized with 2'-hemisuccinyltaxol-BSA synthesized by 2'-hemisuccinyltaxol and BSA. The antiserum titer was determined by RIA using 2'-[$^{125}$I]iodotyramine-hemisuccinyltaxol. The titer of 1:20 was obtained with about 40% of B/T. The results suggest that taxol RIA using $^{125}$I labelled antigen can be applied to monitor the taxol level in serum.

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The Growth Inhibiting Effect of Enterobacteria, Clostridium pefringens KCTC 5014, by the Combination of Natural Products (Clostridium perfringens KCTC 5014의 성장 억제를 위한 항산화 천연산물의 효과)

  • 김종덕
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.6
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    • pp.1119-1125
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    • 2002
  • The growth of C. pefringens was inhibited by the combination of natural products which have antioxidative capacity C. perfringens was controlled very effectively by each or the combination of Paeonia japonica, Atractylodis rhizome alba, Epimedii herba, Acori graminei rhizoma, Schizandraefructus, Lyciifructus, Cinnamomi cortex Sophorae flos Phellodendri cortex, Nelumbo nuclfera gaertner, Asparagi tuber, Mori cortex radicis, Astrafali radix and Coptidis rhizome The combination of Phellodendri cortex, Epimedii herba, Astragali radtx and Glycyrrhizae radix inhibited the growth of C. pefringen by 75% and increased the antioxidative activity by 4.4 times. This combination also eliminated more than 80% of hydroxyl radical. These natural products can be utilized as pharmaceuticals, functional foods, antiaging tea, and multifunctional fermentative beverages.

Effect of Soluble Salts and Their Concentrations on Water Absorption of Polyacrylamide Hydrogel (무기염의 종류 및 농도가 Polyacrylamide 고흡수성 수지의 수분 흡수에 미치는 영향)

  • Wang, Hyun-Jin;Choi, Jong-Myung;Lee, Jong-Suk
    • Journal of Bio-Environment Control
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    • v.14 no.3
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    • pp.196-202
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    • 2005
  • This research was conducted to determine the amount of water absorbed by a polyacrylamide hydrogel such as Stocksorb C (STSB), effect of salts on inhibition in hydration of STSB, and the hydrogel effects on changes of nutrient concentration in external solution. Absorption of deionized water by STSB reached a maximum of 180 $mL{\cdot}g^{-1}$. Monovalent soluble salts such as $KH_2PO_4,\;KNO_3$, and $(NH_4)_2SO_4$ reduced absorption of the hydrogel, but the degrees of inhibition in absorption were similar in three kinds of salts. Twenty milliequivalents per liter of $Ca_{2+}\;or\;Mg_{2+}$ reduced water absorption of STSB to $14\%$ compared to those of deionized water. Solution absorption was consistently lower in the presence of divalent cations than in the presence of the monovalent cations. But the absorption was unaffected by the uncharged salt such as urea in all concentrations tested. The final $K^+\;and\;NH_4^+-N$ concentrations of the solution remaining after absorption by STSB was higher than those of the initial solution. The soaking of STSB to full strength of Hoagland solution resulted in increase of $NO_3^--N,\;H_2PO_4^-\;and\;SO_4^{2-}$ concentrations in external solution compared to initial solution, reaching 5,300, 250 and 1,500 $mL{\cdot}g^{-1}$, respectively, at 24 hrs after soaking.

Preparation of Polyolefin Hollow Fiber Membranes and Their Applications (폴리올레핀계 고분자 중공사막의 제조 및 응용)

  • 김진호;박민수;장문석;김성수
    • Proceedings of the Membrane Society of Korea Conference
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    • 2003.11a
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    • pp.154-154
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    • 2003
  • 세계의 특허동향을 분석해 보면 수처리용 MF/UF 분리막의 제조 및 응용에 관한 연구개발이 매우 활발하게 진행되어져 왔음을 알 수 있다. 또한 다국적 기업들의 적극적인 마케팅과 분리막 공법의 우수한 처리효율이 인정되면서 90년대 후반부터는 수십만톤/일 규모의 징수처리 및 하수고도처리 분야에까지 MF/UF 분리막이 괄목할만한 수요의 증대를 보이고 있으며 이러한 추세는 앞으로도 더욱 확대될 것으로 전망이 되고 있다. 고분자재료를 이용하여 MF/UF 분리막을 제조하는 방법으로는 보편적으로 첫째, 고분자를 용매에 녹인 후 용매와 비 용매간의 상호교환을 유도하여 분리막을 제조하는 상전이법(Phase Inversion). 둘째, 고분자를 고온에서 희석제와 melt-blending 한 후 가해진 열을 제거하면서 상분리를 일으켜 다공성을 부여하는 열유도 상분리법(TIPS, Thermally Induced Phase Separation). 셋째, 결정성 고분자를 용융, 압출 및 냉각하여 결정화도가 매우 높은 전구체를 제조한 후 연신에 의해 비결정 영역을 개열시켜 기공을 형성하는 연신법(Stretching process)이 있다. 이 중 물성이 매우 우수한 폴리올레핀계 결정성 고분자를 이용하여 분리막을 제조할 수 있는 방법은 열유도 상분리법 및 연신법에 제한된다. 본 연구 발표에서는 세계적으로도 극소수의 기업들만이 보유하고 있으며 고도로 축적된 노하우를 필요로 하는 열유도 상분리법 및 연신법에 의하여 폴리프로필렌 및 폴리에틸렌 중공사막을 제조하는 방법과 이 두 가지 방법에 의해서 제조된 중공사막의 구조, 물성 및 수투과 성능 그리고 KMS 중공 사막의 응용사례를 통한 실제 운전특성 등을 소개하고자 한다.좋은 결과를 가져다 주는 술식으로 판단되었다.결과를 이용하여 향후 전개될 홈 네트워크 서비스 및 관련시장의 발전 방향을 전망해 보고 이에 따른 기업이나 정부차원의 대응전략을 파악하고자 한다.육구에서는 큰 변화를 나타내고 있지 않았다(p<0.05). 운동과 비운동시킨 참돔의 지질 함량의 변화는 운동시킨 참돔은 운동으로 인한 에너지 소비로 인하여 함량이 유의적으로 감소했으며(r=-0.35), 비운동사육구에서는 절식으로 인하여 지질함량이 감소하였다(r=-0.38). 파괴강도와 가장 밀접한 영향을 가지는 콜라겐은 운동과 비운동 모두 사육기간동안 큰 변화는 보이지 않았다. 초기의 파괴강도값은 1.45±0.02kg(운동사육구), 1.36±0.18kg(비운동사육구)이였으며 사육기간동안 운동사육구는 파괴강도값이 증가한 반면, 비운동수조에서는 참돔의 파괴강도는 사육기간동안 큰 유의차가 없었다. 각 성분간의 상관도를 살펴보면, 수분함량과 파괴강도는 상관성을 가졌으며, 지질함량과 파괴강도도 같은 경향은 나타내었다. 운동기간동안의 파괴강도와 콜라겐 사이에는 상관성의 거의 없었다. 이는 운동기간에 따른 파괴강도의 증가가 콜라겐의 함량의 증가보다는 지질함량의 감소와 수분함량의 증가와 같은 성분과의 상관성이 크다고 판단된다. 다음으로는, 운동횟수에 의한 영향으로써 운동시간을 1일 6시간으로 설정하여, 운동횟수를 결정하기 위하여 오전, 오후에 각 3시간씩 운동시키는 방법과 오전부터 6시간동안 운동시키는 두 방법을 이용하여 품질을 비교하였다. 각 조건에 따라 운동시킨 참돔의 수분함량을 나타낸 것으로, 2회(오전 3시간, 오후 3시간)에 나누어서 운동시키기 위한 육의 수분함량은 73.37±2.02%를 나타냈으며, 1회(6시간 운동)

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Preparation of BaTiO3 Powder in $BaO2-TiO2-Reduction Agent-PSCA (Particle Size Control Agent) System by SHS and Its Dielectric Properties (B3O2-TiO2-환원제-입자제어제계에서 자전연소합성법에 의한 BaTiO3분말의 제조 및 유전특성)

  • Yun, Ki-Seok;Lim, Sung-Jae;Nersisyan, Hayk;Won, Chang-Whan
    • Journal of the Korean Ceramic Society
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    • v.41 no.11
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    • pp.842-850
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    • 2004
  • We have investigated on the preparation of BaTiO$_3$ powder at the system of BaO$_2$-TiO$_2$-Reduction ag.-PSCA by SHS. C and Mg were used as reduction agent, and NaCl was used as PSCA (Particle Size Control Agent). The effects of the various reduction agent and its concentration, particle size control agent, reaction mixture mass on the product in the preparation of BaTiO$_3$ powder at the optimum system by SHS were investigated. The optimum conditions for reaction system and composition were BaO$_2$+TiO$_2$+0.11 Mg +0.2C+0.75NaCl in the As atmosphere. NaCl as PSCA showed the effect of controlling the particle size of product as well as the combustion temperature. The particle size of BaTiO$_3$ synthesized at the optimum condition was about 0.5 ${\mu}{\textrm}{m}$. And as the mixture mass for the reaction was increased, the more stable combustion wave appeared. We have conducted the sintering experiment at the temperature of 130$0^{\circ}C$, the time of 2 h and the atmosphere of air to measure the dielectric properties of BaTiO$_3$ synthesised in this work, and the sample sintered in this condition showed 2,290 of dielectric constant at 10$0^{\circ}C$ and 13,890 at curie point (129$^{\circ}C$).

Characteristics of Strong Alkaline Electrolyzed Water Produced in All-in-one Electrolytic Cell (일체형 전해조에서 생산된 강알카리성 전해수의 특성)

  • Lee, Ho Il;Rhee, Young Woo;Kang, Kyung Seok
    • Clean Technology
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    • v.18 no.4
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    • pp.446-450
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    • 2012
  • Strong alkaline electrolyzed water which is produced in cathode by electrolyzing the solution where electrolytes (NaCl, $K_2CO_3$ etc.) are added in diaphragm electrolytic cell, is eco-friendly and has cleaning effects. So, it is viewed as a substitution of chemical cleaner. In addition, strong alkaline electrolyzed water is being used by some Japanese automobile and precision parts manufacturing industries. When strong alkaline electrolyzed water is produced by using diaphragm electrolytic cell, it is necessarily produced at the anode side. Since strong acidic electrolyzed water produced is discarded when its utilization cannot be found, production efficiency of electrolyzed water is consequently decreased. Also, there is a weakness electrolytic efficiency is decreasing due to the pollution of diaphragm. In order to overcome this, non-diaphragm all-in-one electrolytic cell integrated with electrode reaction chamber and dilution chamber was applied. Strong alkaline electrolyzed water was produced for different composition of electrolytes, and their properties and characteristics were identified. In comparing the properties between strong alkaline electrolyzed water produced in diaphragm electrolytic cell and that produced in all-in-one electrolytic cell, the differences in ORP and chlorine concentration were found. In emulsification test to confirm surface-active capability, similar results were obtained and strong alkaline electrolyzed water produced in non-diaphragm all-in-one electrolytic cell was identified to be useable as a cleaner like strong alkaline electrolyzed water produced in diaphragm electrolytic cell. Strong alkaline electrolyzed water produced in non-diaphragm all-in-one electrolytic cell is thought to have sterilizing power because it has active chlorine which is different from strong alkaline electrolyzed water produced in diaphragm electrolytic cell.

Percutaneous Endoscopic Gastrostomy Tube Insertion-induced Superior Mesenteric Artery Injury Treated with Angiography (경피 내시경하 위루술 후 발생한 상장간막 동맥 손상 1예)

  • Lee, Seo Hee;Moon, Hee Seok;Park, Jae Ho;Kim, Ju Seok;Kang, Sun Hyung;Lee, Eaum Seok;Kim, Seok Hyun;Sung, Jae Kyu;Lee, Byung Seok;Jeong, Hyun Yong
    • The Korean Journal of Gastroenterology
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    • v.72 no.6
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    • pp.308-312
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    • 2018
  • Percutaneous endoscopic gastrostomy (PEG) is widely used to provide nutritional support for patients with dysphagia and/or disturbed consciousness preventing oral ingestion, and PEG tube placement is a relatively safe and convenient non-surgical procedure performed under local anesthesia. However, the prevention of PEG-insertion-related complications is important. A 64-year-old man with recurrent pneumonia underwent tracheostomy and nasogastric tube placement for nutritional support and opted for PEG tube insertion for long-term nutrition. However, during the insertion procedure, needle puncture had to be attempted twice before successful PEG tube placement was achieved, and a day after the procedure his hemoglobin had fallen and he developed hypotension. Abdominal computed tomography revealed injury to a pancreatic branch of the superior mesenteric artery (SMA) associated with bleeding, hemoperitoneum, and pancreatitis. Transarterial embolization was performed using a microcatheter to treat hemorrhage from the injured branch of the SMA, and the acute pancreatitis was treated using antibiotics and supportive care. The patient was discharged after an uneventful recovery. Clinicians should be mindful of possible pancreatic injury and bleeding after PEG tube insertion. Possible complications, such as visceral injuries or bleeding, should be considered in patients requiring multiple puncture attempts during a PEG procedure.

Research Analysis in Automatic Fake News Detection (자동화기반의 가짜 뉴스 탐지를 위한 연구 분석)

  • Jwa, Hee-Jung;Oh, Dong-Suk;Lim, Heui-Seok
    • Journal of the Korea Convergence Society
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    • v.10 no.7
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    • pp.15-21
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    • 2019
  • Research in detecting fake information gained a lot of interest after the US presidential election in 2016. Information from unknown sources are produced in the shape of news, and its rapid spread is fueled by the interest of public drawn to stimulating and interesting issues. In addition, the wide use of mass communication platforms such as social network services makes this phenomenon worse. Poynter Institute created the International Fact Checking Network (IFCN) to provide guidelines for judging the facts of skilled professionals and releasing "Code of Ethics" for fact check agencies. However, this type of approach is costly because of the large number of experts required to test authenticity of each article. Therefore, research in automated fake news detection technology that can efficiently identify it is gaining more attention. In this paper, we investigate fake news detection systems and researches that are rapidly developing, mainly thanks to recent advances in deep learning technology. In addition, we also organize shared tasks and training corpus that are released in various forms, so that researchers can easily participate in this field, which deserves a lot of research effort.