• Journal of Pharmaceutical Investigation
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• 제28권2호
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• pp.109-113
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• 1998

This study is purposed to develop the sustained release and bioavailability of piracetam (PA). The use of alginate beads as a means to achieve sustained release of piracetam was evaluated in comparison with that of piracetam alone. In the PA-sodium alginate(SA) beads was confirmed by differential scanning calorimetry thermogram(DSC), indicating a relative shift of an endometric peak of PA to higher temperature. The changes in dissolution rates from PA-SA beads and PASA beads coated by chitosan(CHO) were significantly slower than that of intact PA. The release rate of PA-SA in the gastric fluid was markedly decreased compared with that in the intestinal fluid, suggesting that PA is mostly released in the intestinal fluid. However, the PA/SA ratio scarcely affected the release profile. The blood concentration- time curves of PA, PA-SA and PA-SA-CHO were obtained by oral administration to rats. $T_{max}$ of PA, PA-SA and PA-SA-CHO were 1, 10 and 6 hours, respectively. It was confirmed that the release of PA was prolonged by the formulation of PA-SA beads and PA-SA-CHO beads.

• Structural Engineering and Mechanics
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• 제35권6호
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• pp.659-676
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• 2010

An energy-based fatigue life prediction framework was previously developed by the authors for prediction of axial and bending fatigue life at various stress ratios. The framework for the prediction of fatigue life via energy analysis was based on a new constitutive law, which states the following: the amount of energy required to fracture a material is constant. In this study, the energy expressions that construct the new constitutive law are integrated into minimum potential energy formulation to develop new finite elements for uniaxial and bending fatigue life prediction. The comparison of finite element method (FEM) results to existing experimental fatigue data, verifies the new finite elements for fatigue life prediction. The final output of this finite element analysis is in the form of number of cycles to failure for each element in ascending or descending order. Therefore, the new finite element framework can provide the number of cycles to failure for each element in structural components. The performance of the fatigue finite elements is demonstrated by the fatigue life predictions from Al6061-T6 aluminum and Ti-6Al-4V. Results are compared with experimental results and analytical predictions.

• International Journal of Automotive Technology
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• 제4권3호
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• pp.125-133
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• 2003

Several models for the evaluation of Gross Heat Release from the internel combustion engine (ICE) are often used in literature. One of these is the First Law - Single Zone Model (FL-SZM), derived from the First Law of Thermodynamic. This model present a twice advantage: first it describes with accuracy the physic of the phenomenon (charge heat release during the combustion stroke and heat exchange between gas and cylinder wall); second it hat a great simplicity in the mathematical formulation. The evaluation of Heat Release with the FL-SZM is based on pressure experimental measurements inside the cylinder, and ell the assumption of several parameters as the specific heat ratio, wall temperature, polytropic exponent for the motored cycle evaluation, and many others. In this paper the influence of gases thermodynamic properties on Cross Heat Release has been esteemed. In particular the influence of an appropriate equation for k=k(T) (specific heat ratio vs. temperature) which describes the variations of gases thermodynamic properties with the mean temperature inside the cylinder has been evaluated. This equation has been calculated by new V order Logarithmic Polynomials (VoLP), fitting experimental gases properties through the least square methods.

• 소성∙가공
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• 제14권6호
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• pp.496-501
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• 2005

Precipitates, present in most commercial alloys, can have a strong influence on strength and hardening behavior of a single crystal. The effect of thin precipitates on the anisotropy of initial slip resistance and hardening behavior of crystals is modeled in this article. For the convenience of the computational derivation and implementation, the material formulation is given in the unrelated intermediate configuration mapped by the plastic part of the deformation gradient. Material descriptions for the considered two phased aggregates consisting in lattice hardening as well as isotropic hardening and kinematic hardening are suggested. Numerical simulations of various loading cases are presented to discuss and assess the performance of the suggested model. From the results of the numerical simulation, it is found that the suggested model represents the initial plastic anisotropy at least qualitatively well and that it has an improved representation of various characteristic hardening behaviors in comparison with conventional hardening descriptions where the precipitate structure is not reflected.

• 대한한의학방제학회지
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• 제19권1호
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• pp.35-49
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• 2011

Objectives : This study aims to reveal the characteristics of formulas in "Xi$\v{a}$o' Er Y$\`{a}$o Zh$\`{e}$ng Zh$\'{\i}$ Ju$\'{\e}$. Methods : For that objectives, We analyzes formulas in "Xi$\v{a}$o' Er Y$\`{a}$o Zh$\`{e}$ng Zh$\'{\i}$ Ju$\'{\e}$. In the text, 132 formulas were described. To comprehend the formulas, we classified them as several bases. Results : After those analyses, we bring to a conclusion as follows. 1. 30 formulas are described that treated convulsive diseases (j$\={i}$ngf$\={e}$ng, 惊風). Next, g$\={a}$n(疳), parasite infection, diarrhea/dysentery, dermatosis and etc were in the order. 2. Classified by the formulation, Yu$\'{\a}$nj$\`{i}$(圓劑) was the best(70 kinds of formulas, 53%). S$\v{a}$nj$\`{i}$(散劑) was a form of 41 formulas(31%). T$\={a}$ngj$\`{i}$(湯劑) and g$\={a}$oj$\`{i}$(膏劑) were a form of 5 formulas each. 10 formulas were assumed the form of w$\`{a}$iy$\`{o}$ngj$\`{i}$(外用劑). 3. We researched in-depth analysis of Yu$\'{\a}$nj$\`{i}$. As a results, dosage, additive(輔料) and the time to take of Yu$\'{\a}$nj$\`{i}$ were decomposed. Also, the formulas that treated convulsive diseases were analyzed by the herbs classification. Conclusions : Though the formulas that treated convulsive diseases were hard to application at local clinic, overall nosology of pediatrics was reflected comparatively. "Xi$\v{a}$o' Er Y$\`{a}$o Zh$\`{e}$ng Zh$\'{\i}$ Ju$\'{\e}$ was expected to play a role for reconsideration of formulas' formulation.

• Archives of Pharmacal Research
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• 제28권10호
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• pp.1190-1195
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• 2005

The objective of this study was to develop an assay for mequitazine (MQZ) for the study of the bioavailability of the drug in human subjects. Using one mL of human plasma, the pH of the sample was adjusted and MQZ in the aqueous phase extracted with hexane; the organic layer was then evaporated to dryness, reconstituted and an aliquot introduced to a gas chromatograph/mass spectrometer (GC/MS) system with ion-trap detector. Inter- and intra-day precision of the assay were less than 15.1 and $17.7{\%}$, respectively; Inter- and intra-day accuracy were less than 8.91 and $18.6{\%}$, respectively. The limit of quantification for the current assay was set at 1 ng/mL. To determine whether the current assay is applicable in a pharmacokinetic study for MQZ in human, oral formulation containing 10 mg MQZ was administered to healthy male subjects and blood samples collected. The current assay was able to quantify MQZ levels in most of the samples. The maximum concentration ($C_{max}$ was 8.5 ng/mL, which was obtained at 10.1 h, with mean half-life of approximately 45.5 h. Under the current sampling protocol, the ratio of $AUC_{t{\rightarrow}last}$ to $AUC_{t{\rightarrow}{\infty}}$ was $934{\%}$, indicating that the blood collection time of 216 h is reasonable for MQZ. Therefore, these observations indicate that an assay for MQZ in human plasma is developed by using GC/MS with ion-trap detector and validated for the study of pharmacokinetics of single oral dose of 10 mg MQZ, and that the current study design for the bioavailability study is adequate for the drug.

• 디지털융복합연구
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• 제21권2호
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• pp.17-25
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• 2023

본 연구의 목적은 노인 오토바이 운수사고 입원환자의 노인분류에 따른 특성을 분석하여 노인 오토바이 운수사고의 손상 예방 대책을 마련하기 위한 기초자료의 제공에 있다. 2015년~2019년의 질병관리청 퇴원손상심층조사 자료 중 오토바이 운수사고로 입원한 노인 입원환자 1,384명을 대상으로 카이제곱검정, 독립표본 t-검정, 정준상관분석을 실시하였다. 진료 및 치료 정보 특성은 연소 노인과 고령 노인 모두 두개내 손상(S06)이 많았고, 손상 부위와 손상 유형은 각각 머리/목, 골절이 가장 많았다. 손상 발생 장소는 길/간선도로, 손상 시 활동은 이동중이 가장 많았다. 이상의 연구결과로 볼 때, 노인 오토바이 운수사고의 특성을 파악하여 이들을 집중적으로 관리하기 위한 국가적 차원의 예방 교육 및 정책 수립이 필요할 것으로 판단된다. 이 연구는 손상 예방과 감소를 위한 대책 마련 및 정책 개발에 필요한 기초 자료를 제공했다는 점에서 의의가 있다.

• 한국조경학회지
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• 제22권3호
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• pp.41-63
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• 1994

The purpose of this study is to analyze and assess policies and management systems related to traditional villages in Korea. To pursuit this purpose, this study analyzes the applied conservation process to traditional villages. Specifically, it attempts to search for new approaches. Mainly, the using cases are the designated villages protected by law. This study is composed of two major parts. First part is devoted to the understanding of applied conservation process. This work is executed by the introduction of the five stages. ($\circled1$ preliminary investigation, $\circled2$ designation, $\circled3$ main investigation, $\circled4$ planning and design, $\circled5$ management) Based on the results of the first part, the second part is analyzed problems of past and current situation and arranged formulation of suggestions of suggestions for future policy development. This is composed of this items. ($\circled1$ law and institution, $\circled2$ methods of conservation, $\circled3$ investigation and analysis, $\circled4$ management) This study doesn't suggest substantial alternatives, but the analyzed results of this study will contribute to the futher work of conservation for traditional villages in Korea.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.398-401
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• 2006

Dual channel Radiometer for Earth and Atmospheric Monitoring (DREAM) is the main payload on Science and Technology SATellite-2 (STSAT-2) of Korea. DREAM is two-channel microwave radiometer with linear polarization, and operating at center frequencies of 23.8 GHz and 37 GHz. An equation for DREAM calibration is derived which accounts for losses and re-radiation in the microwave components of the radiometer due to physical temperature. This paper describes the radiometric calibration equation to get antenna temperature ($T_A$) from the measured output data. At lower altitude, the measured deep space temperature is contaminated by middle atmosphere and earth radiation. In this paper, we presented the detail mathematical formulation to find the altitude up to which cold source brightness temperature is not affected by earth and middle atmosphere radiation. The DREAMPFM data is used to calculate the performance parameters (linearity, sensitivity, dynamic range, and etc.) of the system.

• 한국전산유체공학회지
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• 제17권1호
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• pp.29-35
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• 2012

Fluid-Structure Interaction analysis of a circular cylinder surrounded by incompressible turbulent flow is presented. The fluid flow is modeled by incompressible Navier-Stokes equations in conjunction with large-eddy simulation for turbulent vortical flows. The circular cylinder is modeled as elastic continuum described by elasto-dynamic equation of motion. Finite element method based approach is utilized for unified formulation of fluid-structure interaction analysis. The magnitude and frequency of structural response is analysed in comparison to the driving fluid forces.