Analysis of the Motion of a Harmonic Oscillator Coupled to Faraday's Law

KIM*, Se-Hun,KO, Tae-Eon,LEE, Se-Hyun,KIM, Kwang-Sun,OH, Seung-Won,KIM, Hyun-Seok Korean Physical Society 2018 새물리 Vol.68 No.1

Electrical quadruple hysteresis in Pd-doped vanadium pentoxide nanowires due to water adsorption

Kim, Byung Hoon,Oh, Soon-Young,Yu, Han Young,Hong, Won G,Yun, Yong Ju,Kim, Yark Yeon,Kim, Hae Jin Elsevier 2010 SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS Vol.11 No.6

<P>Humidity-dependent current–voltage (<I>I–V</I>) characteristics of Pd-doped vanadium pentoxide nanowires (Pd-VONs) were investigated. Electrical quadruple hysteresis (QH) was observed and attributed to the large amount of water molecules adsorbed on the nanowires. Using QH in Pd-VONs, the reaction of water with PdO was interpreted as the water molecules are desorbed and then dissociated with increasing bias voltage. Owing to the dissociated H<SUP>+</SUP> and OH<SUP>−</SUP> ions, PdO is reduced and oxidized. As a result, water molecules recombine as the bias voltage is decreased.</P>

Urinary tissue inhibitor of metalloproteinase-2 and insulin-like growth factor-binding protein 7 as biomarkers of patients with established acute kidney injury

( Won Yong Cho ),( Sung Yoon Lim ),( Ji Hyun Yang ),( Se Won Oh ),( Myung-gyu Kim ),( Sang-kyung Jo ) 대한내과학회 2020 The Korean Journal of Internal Medicine Vol.35 No.3

Background/Aims: Urinary tissue inhibitor of metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) have been recently discovered and validated as sensitive biomarkers that can predict stage 2 or 3 acute kidney injury (AKI) development in high-risk patients. We aimed to assess whether these biomarkers could predict adverse outcomes and renal recovery in established AKI patients. Methods: This was a single-center study prospectively enrolling 124 patients diagnosed with AKI. TIMP-2, IGFBP7, neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury molecule 1 (KIM-1) levels were measured at the time of diagnosis and the predictive performance of short-term outcomes and renal recovery was assessed. Results: Patients were divided into 4 quartiles according to the initial urinary TIMP-2/IGFBP7 levels. Stage 3 AKI (odds ratio [OR], 17.86), classified by the Kidney Disease Improving Global Outcomes (KDIGO), as well as the third and fourth quartiles of TIMP-2/IGFBP7 (OR, 5.75 and 44.98, respectively), were found to be independent predictors of renal replacement therapy at the time of AKI diagnosis. In addition, KDIGO stage 3 AKI (OR, 2.468) or the third of fourth quartiles of urinary TIMP-2/IGFBP7 (OR, 1.896 and 3.622, respectively) were also found to be useful in predicting nonrecovery of renal function. In a separate analysis of patients with renal recovery at discharge, initial urinary TIMP-2/IGFBP7 or urinary IGFBP7 at discharge could also predict new-onset or progressive chronic kidney disease (CKD). Conclusions: In AKI patients, urine TIMP-2/IGFBP7 could serve as a biomarker for predicting adverse outcomes, renal recovery, or the development and progression of CKD.

양궁 선수의 마음챙김 능력 향상을 위한 심리훈련 프로그램 적용

김진호(Kim, Jin-Ho),오원석(Oh, Won-Seok) 한국사회체육학회 2017 한국사회체육학회지 Vol.0 No.67

The purpose of this study is to investigate the effects of mindfulness training with psychological techniques in a professional archery team in South Korea. First of all, it is conducted to find the changes in mindfulness through the KIMS during the mindfulness training, and to analyze the changes in both mindfulness and psychological technique factors. After ten times of meditation (1h-1h30m/1d), ACT and MAC based on the mindfulness training program, there were significant positive influences of psychological factors such as techniques, acceptance, concentration behavior and attention behavior on an intervention group compared to a control group, resulting in KIMS. Although there were no significant differences in confidence and teamwork in the intervention group after the psychological techniques, there were positive effects on willpower, goal setting , concentration, anxiety control and imagery statistically in the intervention group. In conclusion, mindfulness training has positive effects on the mindfulness in Korean archers. This training also has a positive influence on psychological technique factors such as attention, imagery, concentration and anxiety control. According to previous literatures, it is proved that there were positive effects on the psychological technique factors with the changes in mindfulness. Therefore, it is required to develop tools which can measure the mindfulness and to apply the correlation of mindfulness and psychological techniques to the field.

농촌지역 사회적기업의 성과 평가와 지원방안

오내원(Nae-Won Oh),김창호(Chang-Ho Kim),권인혜(In-Hey Kwon),오세익 한국농촌경제연구원 2010 한국농촌경제연구원 기본연구보고서 Vol.- No.-

최근 사회적기업에 대한 관심이 증대하는 가운데 기업으로서의 지속가능성에 우려가 제기되고 있다. 그러나 사회적기업의 지속가능성은 일반 기업과는 달리 평가되어야 한다. 사회적기업에 대한 경영 성과는 해당 기업들이 이룬 사회적 파급효과도 포함되어야 하기 때문이다. 설문조사 결과 농촌지역 사회적기업은 대체로 경영수지 균형을 이루고 있는 것으로 나타났다(90.3%가 흑자 또는 수지균형). 총수입액으로 본 농촌 사회적기업의 경영규모는 평균 4억 4,000만 원 정도로 작은 편이었다. 총 수입액 중 영업수익(매출액)의 비중으로 계산되는 재정자립도는 평균 70%대로 예상보다 높았고 외국과 비교해도 낮은 수준은 아닌 것으로 판단되었다. 그렇지만 30%를 차지하는 외부지원은 대부분 정부지원으로 충당되고 있으며 사회적 기부나 모기관의 지원 비중은 매우 낮았다. 정부지원에 대한 높은 의존도는 정책 변화에 따라 사회적기업의 지속가능성에 문제를 발생시킬 가능성이 큰 것으로 보인다. 농촌지역 사회적기업의 평균 고용규모는 22.5명이고 이 중 절반 정도가 취약계층인 것으로 나타나, 고용창출과 노동통합에도 상당히 기여하고 있다. 총수입 1억 원당 종사자 수가 5명으로 일반 기업에 비해 높은데, 이런 고용효과에도 불구하고 정부에서 지원하는 사회적일자리 창출사업의 지원기간이 1년마다 결정되는 등 사회적기업의 고용이 오히려 경영 불안정 요소로 작용하고 있기도 하다. 사회적기업의 경영 애로와 관련해서는 투자 확대의 어려움, 불리한 시장조건이 가장 큰 문제로 확인되었다. 대체로 사회적기업의 수익성이 취약해 자체 자금조달이 어렵고 외부적으로도 낮은 사업성 평가와 담보력 부족으로 금융기관에 대한 접근이 쉽지 않은 것으로 나타났다. 또 농촌 사회적기업은 자본과 기술의 부족, 저효율 노동력, 구매력이 부족한 고객, 농촌의 열악한 산업인프라 등 시장에서 경쟁력을 갖기에 불리한 조건이 많은 것으로 파악되었다. 이러한 점을 고려할 때 농촌지역 사회적기업에 대한 경제적 지원 방향은 다음과 같이 제시할 수 있다. 먼저 정부의 독점적인 인증제도를 본원적인 사회적기업의 의미와 실천을 훼손하지 않도록 개선해야 한다. 아울러 농촌지역에서 발견되는 다양한 자발적 노력들을 사회적 목적활동으로 인정할 필요가 있다. 둘째, 사회적기업에 대한 지원도 획일적인 인건비 지원보다는 구체적인 활동내용과 경영상의 애로점에 대응하여 차별적으로 주어져야 한다. 특히 관계 부처들의 사업들과 연계하여 사회적기업에 대한 투자를 지원할 수 있어야 하며, 사회적 투자기금을 조성해 금융조달에 대한 숨통을 틀 수 있도록 지원해야 한다. 농촌지역 사회적기업의 취약한 시장경쟁력을 보완해 줄 수 있는 보호시장의 제공, 바우처사업 등에 대한 참여 실적 등을 평가하여 경제적 보상으로 되돌려 주는 방안도 적극 모색되어야 한다. 셋째, 농촌지역 현실과 특성에 적합한 사업모델을 개발하고 보급해야 한다. 특히 농업 생산?유통?가공 사업에의 진출이 중요한데 시장경쟁이 심해짐에 따라 위험도가 높다. 따라서 지역 내의 인적?물적 연계를 활용한 사업모델 구축이 핵심과제이다. 문화예술활동은 당장은 수익구조를 맞추기 어렵지만 삶의 질 향상과 지역경쟁력의 원천이란 점에서 보호된 시장을 전제로 다양한 사업모델을 구상할 수 있을 것이다. Recently, while our concern about the social enterprise has grown, the anxiety of its sustainability has raised. However, the sustainability must be evaluated differently from general enterprises, because its social effects should be included in the social enterprise"s performance. The result of survey shows that business performances of social enterprises located in rural areas are generally balanced in terms of profit and cost. Their business volumes in terms of revenue are quite small by 440 million won. Their financial independency rate reached about 70 percent. This figure is over our expectation and is not low compared to foreign enterprises. Thirty percent of supports come from government supports and the weight of donation and mother body support is very low. The high level of government support can cause problems in the sustainability according to the change of government policies. The average number of employee of social enterprises is 22.5 persons. About the half of them comes from the vulnerable class. This fact shows that social enterprises contribute to the generation of employment and labor integration. Even though five persons of employee per 100 million won of revenue is higher than general business, the government policy for employment generation may have an effect on the unstability of business. We confirmed that the lower level of investment and the disadvantage of market conditions are difficulty in social enterprise business of rural areas. They cannot mobilize investments because of low profits and cannot easily approach to the financial institutes due to the lower level of security and profitability. Also, they have many disadvantages such as the lacks of capital and technology, inefficient labor, customers with low purchasing power, and the weak industrial infrastructures. Under these unfavorable conditions, we suggest several alternatives to support social enterprises in rural areas. First, government monopolistic certification system need to be modified in order not to damage the intrinsic meaning and practice of the social enterprise. Various voluntary efforts happening in the rural areas are needed to be admitted as a social goal directed activities. Second, government support should be provided differently according to substantial activities and business difficulties, not uniformed labor cost. Included are investment support connected with government departments" programs, the generation of funds, affirmative action of supplementing markets and etc. Third, business model should be developed and provided appropriate to the realistic characteristics of rural areas. The entry into agricultural production, distribution and processing is very important. However, it is very risky due to competitiveness. The core task is to build business model in connection with regional persennel and materials. The cultural arts activities would be a good business model in term of the quality of life and strong regional competitiveness.

EAF Slag의 해양복토제 활용을 위한 PO₄<SUP>­</SUP>-P 제거특성에 관한 연구

김재원(Jae-Won Kim),서종범(Jong-Beom Seo),강민경(Min-Gyeong Kang),김인득(In-Deuk Kim),오광중(Kwang-Joong Oh) 한국청정기술학회 2010 청정기술 Vol.16 No.4

본 연구에서는 제강전기로 슬래그를 해양복토제로 활용하기 위한 인제거 특성실험을 실시하였다. 제강전기로 슬래그의 PO₄<SUP>-</SUP>-P 제거 특성에 관한 시험 결과, 슬래그 내의 CaO는 Ca<SUP>2+</SUP>와 OH<SUP>-</SUP>로 이온화됨에 따라 PO₄<SUP>-</SUP>-P와 반응하여 HAP를 형성함으로써 용액 중에 존재하는 PO₄<SUP>-</SUP>-P를 효과적으로 제거하는 것으로 나타났다. 연속반응기를 통한 해수 내 PO₄<SUP>-</SUP>-P의 지속적인 유입에 대한 제거특성을 확인한 결과, 칼럼 내 PO₄<SUP>-</SUP>-P 농도는 반응 3일 이후 급격히 감소하여 10일 이후에는 0.5 ppm 이하로 나타났다. 실제 연안해역의 저질을 이용한 제강전기로 해양복토제 적용실험 결과, 반응 25일 후 PO₄<SUP>-</SUP>-P 발생량을 93∼ 98% 저감시키는 것으로 나타났다. 이러한 결과를 바탕으로 제강전기로 슬래그를 해양복토제로 활용할 경우 PO₄<SUP>-</SUP>-P 제거 및 억제효과가 있으며, 파쇄선별 등 별도의 추가공정 없이 적은 량으로도 사용 가능할 것으로 판단된다. This study estimated the possibility of phosphate removal characteristics to utilize EAF(electric arc furnace) slag as submarine cover material. The major phosphate removal mechanism was a certain formation of HAP precipitation occurred by the ionization reaction between Ca<SUP>2+</SUP> and OH<SUP>-</SUP>, which were leached from the EAF Slag. Another phosphate removal mechanism was the adsortion of EAF slag surface. As a result of PO₄<SUP>-</SUP>-P removal characteristics using continuous column reactor, PO₄<SUP>-</SUP>-P concentration decreased rapidly after 3 days and 10 days later, it show under 0.5 ppm. The result as applied in real sea water, shows that the phosphate removal effects were 93∼98% by the subaqueous sediment removal using the EAF slag. In conclusion, EAF slag is useful in PO₄<SUP>-</SUP>-P removal and control and it is possible to use without additional process like crush and selection.

해군 근무환경에서 노출될 수 있는 염화알루미늄의 피부독성 예방을 위한 보호크림 개발 및 효능평가

박창용(Chang-Yong Park),어원석(Won Souk Eoh),이준원(Joon-Won Lee),오영현(Young-Hyun Oh),정미경(Mi Kyoung Jung),김병직(Byungjick Kim2) 한국해군과학기술학회 2023 Journal of the KNST Vol.6 No.3

Controlled Crystal Growth of Two-Dimensional Layered Nanomaterials in Hydrogel via a Modified Electrical Double Migration Method

Gwak, Gyeong-Hyeon,Kwon, Na Kyung,Lee, Won-Jae,Paek, Seung-Min,Kim, So Youn,Oh, Jae-Min The American Chemical Society 2017 CRYSTAL GROWTH AND DESIGN Vol.17 No.12

<P>Layered double hydroxide (LDH) nanomaterials of uniform size and homogeneous distribution are successfully developed in agarose hydrogel through the electrical double migration method. To grow LDH crystals in agarose matrix, both cationic (Ni<SUP>2+</SUP>, Ga<SUP>3+</SUP>) and anionic precursors (OH<SUP>–</SUP> and CO<SUB>3</SUB><SUP>2–</SUP>) of LDH are simultaneously transported from solution to agarose hydrogel through electric potential, resulting in the in situ crystal growth of LDH. X-ray diffraction patterns, X-ray absorption spectra, and high-resolution transmission electron microscopic images confirm that the developed LDH is ∼15 nm in size and had a well-defined crystal structure. Scanning electron microscopy and small-angle X-ray scattering spectroscopy showed homogeneous arrays of LDH nanocrystals along agarose sheets with homogeneous distribution. On the basis of the characterization results, we suggest that crystal nuclei are first developed on the agarose chain, and then LDHs homogeneously grow along sheets of agarose matrix.</P><P>Layered double hydroxides (LDHs) of uniform size and homogeneous distribution are developed in agarose hydrogel through the electrical double migration method. Developed LDH had a well-defined crystal structure and homogeneous arrays along agarose sheets with homogeneous distribution. Thus, we suggest that crystal nuclei are first developed on the agarose chain, and then LDHs homogeneously grow along sheets of agarose matrix.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cgdefu/2017/cgdefu.2017.17.issue-12/acs.cgd.7b01252/production/images/medium/cg-2017-01252b_0009.gif'></P>

Acid etching of glass-infiltrated zirconia and its biological response

Van Thi Vu,Gye-Jeong Oh2,Kwi-Dug Yun,Hyun-Pil Lim,Ji-Won Kim,Thao Phuong Thi Nguyen,Sang-Won Park 대한치과보철학회 2017 The Journal of Advanced Prosthodontics Vol.9 No.2

PURPOSE. The purpose of this study was to evaluate the influence of acid etching treatment on surface characteristics and biological response of glass-infiltrated zirconia. MATERIALS AND METHODS. A hundred zirconia specimens were divided into four groups depending on surface treatments: untreated zirconia (group Z); acid-etched zirconia (group ZE); glass-infiltrated zirconia (group ZG); and glass-infiltrated and acid-etched zirconia (group ZGE). Surface roughness, surface topography, surface morphology, and Vickers hardness of specimens were evaluated. For biological response test, MC3T3-E1 cell attachment and proliferation on surface of the specimens were examined. The data were statistically analyzed using one-way ANOVA and Tukey’s HSD test at a significance level of 0.05. RESULTS. Group ZGE showed the highest surface roughness (Ra = 1.54 μm) compared with other groups (P < .05). Meanwhile, the hardness of group Z was significantly higher than those of other groups (P < .05). Cell attachment and cell proliferation were significantly higher in group ZGE (P < .05). CONCLUSION. We concluded that effective surface roughness on zirconia could be made by acid etching treatment after glass infiltration. This surface showed significantly enhanced osteoblast cell response.

열처리에 따른 Peroxo Titanium Complex 졸 용액 기반 TiN/TiO₂/FTO Resistive Random-Access Memory의 전기적 특성

임현민,이진호,김원진,오승환,서동혁,이동희,김륜나,김우병,Yim, Hyeonmin,Lee, Jinho,Kim, Won Jin,Oh, Seung-Hwan,Seo, Dong Hyeok,Lee, Donghee,Kim, Ryun Na,Kim, Woo-Byoung 한국재료학회 2022 한국재료학회지 Vol.32 No.9

A spin coating process for RRAM, which is a TiN/TiO₂/FTO structure based on a PTC sol solution, was developed in this laboratory, a method which enables low-temperature and eco-friendly manufacturing. The RRAM corresponds to an OxRAM that operates through the formation and extinction of conductive filaments. Heat treatment was selected as a method of controlling oxygen vacancy (V_O), a major factor of the conductive filament. It was carried out at 100 ℃ under moisture removal conditions and at 300 ℃ and 500 ℃ for excellent phase stability. XRD analysis confirmed the anatase phase in the thin film increased as the heat treatment increased, and the Ti³⁺ and OH- groups were observed to decrease in the XPS analysis. In the I-V analysis, the device at 100 ℃ showed a low primary SET voltage of 5.1 V and a high ON/OFF ratio of 10⁴. The double-logarithmic plot of the I-V curve confirmed the device at 100 ℃ required a low operating voltage. As a result, the 100 ℃ heat treatment conditions were suitable for the low voltage driving and high ON/OFF ratio of TiN/TiO₂/FTO RRAM devices and these results suggest that the operating voltage and ON/OFF ratio required for OxRAM devices used in various fields under specific heat treatment conditions can be compromised.