• 제목/요약/키워드: solution structure

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Minimally Complex Problem Set for an Ab initio Protein Structure Prediction Study

  • Kim RyangGug;Choi Cha-Yong
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제9권5호
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    • pp.414-418
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    • 2004
  • A 'minimally complex problem set' for ab initio protein Structure prediction has been proposed. As well as consisting of non-redundant and crystallographically determined high-resolution protein structures, without disulphide bonds, modified residues, unusual connectivities and heteromolecules, it is more importantly a collection of protein structures. with a high probability of being the same in the crystal form as in solution. To our knowledge, this is the first attempt at this kind of dataset. Considering the lattice constraint in crystals, and the possible flexibility in solution of crystallographically determined protein structures, our dataset is thought to be the safest starting points for an ab initio protein structure prediction study.

Structure of an Antimicrobial Peptide Buforin II

  • Yi, Gwan-Su;Park, Chan-Bae;Kim, Sun-Chang;Chaejoon Cheong
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1996년도 정기총회 및 학술발표회
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    • pp.29-29
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    • 1996
  • The structure of an antimicrobial peptide buforin II has been studied by $^1$H NMR and CD spectroscopy. Buforin II is flexible and random structure in H$_2$O but the parts of buforin II become helical structure in trifluoroethanol (TFE)/H$_2$O (1:1, v/v) solution. From the restrained molecular dynamics calculation using NMR data, we obtained the possible conformation of buforin II in TFE/H$_2$O solution. (omitted)

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Improved Sensitivity of a Glucose Sensor by Encapsulation of Free GOx in Conducting Polymer Micropillar Structure

  • Jung, Shin-Hwan;Lee, Young-Kwan;Son, Yong-Keun
    • Journal of Electrochemical Science and Technology
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    • 제2권2호
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    • pp.124-129
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    • 2011
  • A simple process of fabricating micropillar structure and its influence upon enhancing electrochemical biosensor response were studied in this work. Conducting polymer PEDOT was used as a base material in formulating a composite with PVA. Micro porous PC membrane filter was used as a template for the micropillar of the composite on ITO electrode. This structure could provide plenty of encapsulating space for enzyme species. After dosing enzyme solution into this space, Nafion film tent was cast over the pillar structure to complete the micropillar cavity structure. In this way, the encapsulation of enzyme could be accomplished without any chemical modification. The amount of enzyme species was easily controllable by varying the concentration of the dosing solution. The more amount of enzyme is stored in the sensor, the higher the electrochemical response is produced. One more reason for the sensitivity improvement comes from the large surface area of the micropillar structure. Application of 0.7 V produced the best current response under the condition of pH 7.4. This biosensor showed linear response to the glucose in 0.1~1 mM range with the average sensitivity of $14.06{\mu}A/mMcm^2$. Detection limit was 0.01 mM based on S/N = 3.

가압형 정삼투 시 압력에 따른 정삼투막의 Structure Parameter 변화양상 예측 (Structure Parameter Change Estimation of a Forward Osmosis Membrane Under Pressurized Conditions in Pressure-assisted Forward Osmosis (PAFO))

  • 국승호;김성조;이진우;황문현;김인수
    • 멤브레인
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    • 제26권3호
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    • pp.187-196
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    • 2016
  • 최근 정삼투(FO) 공정의 성능향상을 위해 유입수에 낮은 수압을 가하는 가압형 정삼투(PAFO) 공정이 관심을 받고 있다. Structure parameter는 FO 및 PAFO 공정 운전시 유도용질의 확산 저항성(Solute resistivity)을 결정하며, 이는 Solution-diffusion model (S-D model)을 통한 수투과 및 염투과 성능 예측을 지배하는 인자 중에 하나이다. 본 연구는 S-D model을 이용하여 가압형 정삼투시 유입수 측에 가해지는 압력에 따른 Structure parameter 변화 양상을 예측하고자 하였다.

대향류 확산화염에서 확산-전도 불안정의 비선형 거동에 대한 수치해석 (Numerical Simulations on Nonlinear Behaviors of Diffusional-Thermal Instabilities in Counterflow Diffusion Flames)

  • 이수룡;김종수
    • 대한기계학회논문집B
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    • 제26권5호
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    • pp.695-702
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    • 2002
  • Nonlinear dynamics of striped diffusion flames, by the diffusional-thermal instability with Lewis numbers sufficiently less than unity, is numerically investigated by examining various two-dimensional flame-structure solutions. The Lewis numbers for fuel and oxidizer are assumed to be identical and an overall single-step Arrhenius-type chemical reaction rate is employed in the model. Particular attention is focused on identifying the flame-stripe solution branches corresponding to each distinct stripe pattern and hysteresis encountered during the transition. At a Damkohler number slightly greater than the extinction Damkohler number, eight-stripe solution first emerges from one dimensional solution. The eight-stripe solution survives Damkohler numbers much smaller than the extinction Damkohler number until the transition to four-stripe solution occurs at the first forward transition Damkohler number. At the second forward transition Damkohler number, somewhat smaller than the first transition Damkohler number, the transition to two-stripe solution occurs. However, anu further transition from two-stripe solution to one-stripe solution is not always possible even if one-stripe solution can be independently accessed for particular initial conditions. The Damkohler number ranges for two-stripe and one-stripe solutions are found to be virtually identical because each stripe is an independent structure if distance between stripes is sufficiently large. By increasing the Damkohler number, the backward transition can be observed. In comparison with the forward transition Damkohler numbers, the corresponding backward transition Damkohler numbers are always much greater, thereby indicating significant hysteresis between the stripe patterns of strained diffusion flames.

수액 소진 알람시스템을 위한 동일평면형 광센서의 연구 및 제작 (Optical Sensor of Coplanar Structure Study and Design for Intravenous Solution Exhaustion Alarm System)

  • 박효순;김태윤;정의성;성기웅;김명남;조진호
    • 센서학회지
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    • 제24권2호
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    • pp.113-118
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    • 2015
  • Intravenous (IV) infusion set is one of the most common treatment methods applied to hospitalized patients. However, it is necessary to check the injection of IV solution in order to prevent patients from any possible medical injuries. In this paper, using the optical sensors to detect exhaustion of IV solution was proposed. The optical sensor is coplanar structure composed of LED and photodiode which is installed according to focal distance of the lens. These two elements detect exhaustion of IV solution at the desired point conveniently. Through the results of experiments using various wavelength of LED (R.G.B), the blue LED was selected to the optimum light source. The suggested optical sensor can detect exhaustion of IV solution by the differences in the amount of light which is caused by properties such as total reflection, refractive index and scattering. From the implementation, the detector is applicable to both containers of IV solution, glass bottle and plastic pack. And also the result shows apparent differences according to existence of IV solution even if the IV solution color and illumination were changed.

리튬용액침투법에 의한 내열충격성이 향상된 세라믹 제조 (Fabrication of Porcelains Having Improved Thermal Shock Resistance by a Lithium Solution Infiltration Method)

  • 나상문;이상진
    • 한국세라믹학회지
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    • 제50권2호
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    • pp.127-133
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    • 2013
  • Porcelain with high thermal shock resistance was successfully fabricated by a lithium solution infiltration method with a lithium hydroxide solution. Lithium hydroxide solutions having various lithium concentrations were infiltrated into pre-sintered porcelain bodies. The porcelain sample infiltrated by the 9 wt% lithium solution and heat treated at $1250^{\circ}C$ for 1 h showed a low thermal expansion coefficient of $1.0{\times}10^{-6}/^{\circ}C$ with excellent thermal shock resistance. The highly thermally resistant porcelain had a well-developed ${\beta}$-spodumene phase with the general phases observed in porcelain. Furthermore, the porcelain showed a denser structure of $2.41g/cm^3$ sintering density and excellent whiteness in comparison with commercial thermally resistible porcelains. The lithium hydroxide in the samples readily reacted with moisture, and liquid phase reactants were formed during the fabrication process. In the case of an excess amount of lithium in the sample body, the lithium reactants were forced to the surface and re-crystallized at the surface, leaving large pores beneath the surface. These phenomena resulted in an irregular structure in the surface area and led to cracking in samples subjected to a thermal shock test.

통합보안관리 시스템에서 내부 보안을 향상시킨 보안 솔루션 구조의 설계 및 구현 (Design and Implementation of Security Solution Structure to Enhance Inside Security in Enterprise Security Management System)

  • 김석수;강민균
    • 한국콘텐츠학회논문지
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    • 제5권6호
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    • pp.360-367
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    • 2005
  • 인터넷의 보급으로 인해 기업의 전산화가 발전함에 따라, 바이러스, 전산망 침해 등 정보화의 역기능도 크게 증가하고 있다. 따라서 오늘날, 기업 보안의 중요성이 매우 강조되고 있다. 이렇게 보안의 중요도가 높아짐으로 인하여 보안 솔루션도 함께 발전하고 있다. 보안 솔루션은 기존 단일 체제에서 통합 보안 관리 시스템으로 발전하고 있으며 통합보안관리 시스템에서 중요한 것은 각 보안 솔루션의 기능과 정책 의 적합한 설계이다. 기존의 보안 정책은 외부의 침입으로 부터의 보안을 중요시 해왔으나 현재는 내부의 보안도 그 중요도가 높아지고 있다 이를 위하여 새로운 구조의 통합 보안관리 시스템을 구축해야 한다. 본 논문에서는 침입탐지차단 시스템을 활용하여 내부보안을 강화한 통합 보안 관리 시스템을 제안, 구현하였으며. 내 외부의 IP와 ID접근을 실험하여 그 결과를 분석하였다.

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Properties of Dy-doped $La_2O_3$ buffer layer for Fe-FETs with Metal/Ferroelectric/Insulator/Si structure

  • Im, Jong-Hyun;Kim, Kwi-Jung;Jeong, Shin-Woo;Jung, Jong-Ill;Han, Hui-Seong;Jeon, Ho-Seung;Park, Byung-Eun
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 하계학술대회 논문집
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    • pp.140-140
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    • 2009
  • The Metal-ferroelectric-semiconductor (MFS) structure has superior advantages such as high density integration and non-destructive read-out operation. However, to obtain the desired electrical characteristics of an MFS structure is difficult because of interfacial reactions between ferroelectric thin film and Si substrate. As an alternative solution, the MFS structure with buffer insulating layer, i.e. metal-ferroelectric-insulator-semiconductor (MFIS), has been proposed to improve the interfacial properties. Insulators investigated as a buffer insulator in a MFIS structure, include $Ta_2O_5$, $HfO_2$, and $ZrO_2$ which are mainly high-k dielectrics. In this study, we prepared the Dy-doped $La_2O_3$ solution buffer layer as an insulator. To form a Dy-doped $La_2O_3$ buffer layer, the solution was spin-coated on p-type Si(100) wafer. The coated Dy-doped $La_2O_3$ films were annealed at various temperatures by rapid thermal annealing (RTA). To evaluate electrical properties, Au electrodes were thermally evaporated onto the surface of the samples. Finally, we observed the surface morphology and crystallization quality of the Dy-doped $La_2O_3$ on Si using atomic force microscopy (AFM) and x-ray diffractometer (XRD), respectively. To evaluate electrical properties, the capacitance-voltage (C-V) and current density-voltage (J-V) characteristics of Au/Dy-doped La2O3/Si structure were measured.

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성견의 연속 양측 폐이식을 이용한 폐보존 평가 연구 (Evaluation of Lung Preservation by Using of Canine Bilateral Sequential Lung Tranplantation)

  • 박창권;김재범;유영선;권건영;전석길;김정식
    • Journal of Chest Surgery
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    • 제33권5호
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    • pp.377-384
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    • 2000
  • Background: Numerous studies of safe, long term preservation for lung transplantation have been performed using ex vivo models or in vivo single lung transplantation models. However, a safe preservation time which is applicable for clinical use is difficult to determine. We prepared LPDG solution for lung preservation study. In this study we examined the efficacy of LPDG(low potassium dextran glucose) solution in 24-hour lung preservation by using a sequential bilateral canine lung allotransplant model. Material and Method: Seven bilateral lung transplant procedures were performed using weight-matched pairs(24 to 25kg) of adult mongrel dogs. The donor lungs were flushed with LPDG solution and maintained hyperinflated with 100% oxygen at 1$0^{\circ}C$ for a planned ischemic time of 24 hours for the lung implanted first. After sequential bilateral lung transplantation, dogs were maintained on ventilators for 3 hours: arterial resistance were determined if the recipients hourly after bilateral reperfusion and compared with pretransplant-recipient values, which were used as controls. After 2hours of reperfusion, the chest X-ray, computed tomogram and lung perfusion scan were performed for assessmint of early graft lung function. Pathological examinations for ultrastructural findings of alveolar structure and endothelial structure of pulmonary artery were performed. Result: Five of seven experiments successfully finished the whole assessments after bilateral reperfusion for three hours. Arterial oxygen tension in the recipients was markedly decrased in immediate reperfusion period but gradually recovered after reperfusion for three hours. The pulmonary artery and pulmonary vascular resistance showed singificant elevation(p<0.05 versus control values) but also recovered after reperfusion for three hours(p<0.05 versus immediate period value). The ultrastructural findings of alveolar structure and endothelial structure of pulmonary artery showed reversible mild injury in 24 hours of lung perservation and reperfusion. Conclusion : This study suggests that LPDG solution provides excellent preservation in a canine model in which the dog is completely dependent on the function of the transplanted lung.

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