• Journal of the Korea Concrete Institute
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• v.28 no.4
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• pp.489-496
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• 2016

Recently, a concern about hollow core precast concrete (PC) slab has been increased as a method to improve the construction ability by reducing the self weight of structures during the construction. Hollow core slab which is known as a typical PC slab in domestic construction of PC building has a problem to put shear reinforcements in the web of element during the production of element in the factory. With regard to this point, recently, tripple ribs slab (TRS) which can be said as a new type of half PC slab system was developed. In TRS, it is possible to place shear reinforcements in PC element during the production of the element in the factory. This paper presents the shear test result of TRS which was done by one point loading test under simple support condition. Test parameters are the presence of cast-in-place (CIP) concrete and the contribution of lattice bars. From the test, it was found that the TRS has sufficient shear capacity to resist the design load and its strength can be predicted by the code equations for general beam. It is recommended to ignore the strength of lattice bar in the calculation of shear strength during the construction since its contribution is too low to be considered when CIP is not casted.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.1
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• pp.91-105
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• 2016

Carbon Nanotube Field-Effect Transistors (CNTFETs) have been studied as candidates for post Si CMOS owing to the better electrostatic control and high mobility. To enhance the immunity against short - channel effects (SCEs), the novel channel and gate engineered architectures have been proposed to improve CNTFETs performance. This work presents a comprehensive study of the influence of channel and gate engineering on the CNTFET switching, high frequency and circuit level performance of carbon nanotube field-effect transistors (CNTFETs). At device level, the effects of channel and gate engineering on the switching and high frequency characteristics for CNTFET have been theoretically investigated by using a quantum kinetic model. This model is based on two-dimensional non-equilibrium Green's functions (NEGF) solved self - consistently with Poisson's equations. It is revealed that hetero - material - gate and lightly doped drain and source CNTFET (HMG - LDDS - CNTFET) structure can significantly reduce leakage current, enhance control ability of the gate on channel, improve the switching speed, and is more suitable for use in low power, high frequency circuits. At circuit level, using the HSPICE with look - up table(LUT) based Verilog - A models, the impact of the channel and gate engineering on basic digital circuits (inverter, static random access memory cell) have been investigated systematically. The performance parameters of circuits have been calculated and the optimum metal gate workfunction combinations of ${\Phi}_{M1}/{\Phi}_{M2}$ have been concluded in terms of power consumption, average delay, stability, energy consumption and power - delay product (PDP). In addition, we discuss and compare the CNTFET-based circuit designs of various logic gates, including ternary and binary logic. Simulation results indicate that LDDS - HMG - CNTFET circuits with ternary logic gate design have significantly better performance in comparison with other structures.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.2
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• pp.229-236
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• 2017

This study was performed to optimize yanggaeng processing conditions prepared with different amounts of steamed Liriopis tuber (SLT) extract, sugar, and agar powder using response surface methodology. The experimental conditions were designed according to the central composite design with 16 experimental points, including two replicates for three independent variables. The experimental data on physicochemical properties, textural properties, and sensory evaluation were fitted to various models, and the accuracy of the equations was analyzed by ANOVA. Among the responses, pH, water content, sugar content, L-value, browning index, chewiness, gumminess, and sensory properties of appearance, color, sweetness, hardness, texture, and overall acceptability showed significant correlation with contents of SLT, sugar, and agar powder. From these results, optimum formulation of yanggaeng was calculated as follows: SLT 35 mL, sugar 55.23 g, and agar powder 3.39 g.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.6
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• pp.731-742
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• 2010

Modeling of rubber for design or analysis often requires confusing or complex work because there are a large number of constitutive models to be considered. Some models have few material constants, while others have many. Researchers have to prepare and fit extensive experimental data with caution and discretion. In this paper, we first compared some typical rubber models in which deformation was carried out by stretching up to around eight times the original size. We conclude that continuum-based models and chain molecular models can be used in the study of the small deformation in most engineering applications, but chain molecular models are preferred in the study of the large deformations in most biomaterial applications. As discrimination problems, Treloar's patch and cylindrical balloon stick are tested theoretically and numerically for studying bifurcation. In the case of Treloar's patch, by using the Kearsley's equation, we show that bifurcation exists for continuum-based models but not for chain molecular models. Both models show bifurcation in the cylindrical balloon stick. Therefore, in the analysis of the bifurcation of rubber showed that its existence also depends on the constitutive model selected.

• Fashion & Textile Research Journal
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• v.1 no.4
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• pp.376-386
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• 1999

The purpose of this study was to determine the physiological responses and the Subjective sensations of the human subjects when 10 human subjects(5 males and 5 females) were tested with selected ensembles, including the uniforms of students, industrial and bank workers. For the study, garment material and design were selected, which was mostly used in Taegu area by the survey. Thermal manikin and the human subject tests were performed. The results were as follows: 1. There was no significant difference among skin temperature of head by season and among that of breast and back by all variables, however, there was a significant difference among that of belly by gender and that of thigh and shank by season. In addition, there was no significant difference among rectal temperature by gender and season, but there was a significant difference by uniform. 2. Mean skin temperature of male subjects was significantly higher than that of female subjects. Specially in lower environmental condition, the difference got larger. 3. There was a significant difference among purse rate of subjects by uniform, but there was no significant difference among those by gender and season. There were no significant difference among maximum and minimum blood pressure by gender, uniform, and season. 4. There was a significant difference in temperature of chest among gender and uniform, and there was no significant difference in temperature of back by season. In addition, There was a significant difference in humidity of back by uniform and season but there were no significant difference in that by gender. 5. There was a significant difference in humidity sensation by gender, comfort sensation by uniform and season, but there was no significant difference thermal sensation by uniform and season. 6. For the result of regression analysis, we got the regression equations as follows: Clo=1.810 Thickness+0.525, Clo=0.475 weight+0.863.

• Journal of Korean Tunnelling and Underground Space Association
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• v.10 no.3
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• pp.233-243
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• 2008

A tunnel behavior predicted in the investigation and design stage is often different from its actual behavior due to mainly the complexity of ground conditions. In a tunnel construction, therefore, it is necessary to ensure the stability of the tunnel by predicting the behaviors of the ground and the supports through observations and measurements, and modifying immediately excavation and reinforcing methods when necessary. To do so, it is important to be able to predict the final tunnel behavior based on the initial tunnel behavior as early as possible. In this study, the correlations were obtained between the initial and the final convergence by analyzing statistically the convergence measurement data, collected from two domestic road tunnels under construction using NATM. In order to estimate the unknown displacements, occurred during the period between the excavation and the first measurement, two methods were used - one is the method by means of regression analysis using a modified exponential function and the other the method by a simple linear regression analysis using the data measured within the distance from tunnel face equal to the tunnel diameter (D). Finally, the relationships were obtained between the initial and final convergence, including the non-measured displacements estimated from the two different methods, by performing linear regression analyses. The regression analysis results showed that there are clear linear relationships between the initial and final convegence and the difference between the two linear regression equations was not that large for when using the exponential function and the simple linear function to estimate the non-measured displacements.

• The Journal of the Acoustical Society of Korea
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• v.16 no.6
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• pp.5-11
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• 1997

Recently, the search for the whereabout of the huge Bell Imperial-Dragon-Temple becomes a great issue. If it happens to be found out and ringing at the original location of the Bell in Kyungjoo City, the Bell might be a great national treasure and lasting to the eternity with her beautiful sound. The Bell was so huge that the total weight of the raw material put into crucibles was 497,581 Kun (289 tons), the shoulder weight 10.3 Chuk (3.14 m) and the maximum thickness 9 Chon (27.4 cm). The Bell was erected in 754 in Shilla Dynasty and was assumed to be lost during the war time by the 3rd invasion of Mongolians (1235~8). However, the author found out that the huge Bell was recast into a new small Bell (8.1 ton) in 1103 by the people of Koryu Dynasty and then the new small Bell was hung in the same position as in the original huge Bell. 135 years later, the new small Bell was carried out by Mongolian forces as a spoil of war from Kyungjoo to the Bay Tonghaegoo, through the saddle point of Mountain Toham, Yangbuk and Riber Great Bell. At the bay, Mongolian forces wished to bring back the Bell to Mongolia by a ship, but they dropped the Bell into the sea by accident. So, if this was the case, the bell at the seabed may be the new small bell (7.4 ton) but not the original huge Bell (41.0 ton) For the evaluation of missing data of the two bells, the author sets up two equations relating all the dimensions and their weights, which seems to be a useful guide to the design of bells. The results of the evaluation of the Bells are as follows. The huge Bell The new small Bell Weight 41.0 ton 7.4 ton Shoulder ht. 3.14 m 2.07 m Mouth diameter 2.468 m 1.546 m Max. thickness 27.4 cm (9 Chon) 11.9 cm (3.9 Chon)

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.472-477
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• 2003

멸종위기종의 서식지를 효율적으로 관리하기 위해서는 해당 종의 서식 가능한 지역의 분포를 알아야 한다. 본 연구의 목적은 GIS와 퍼지집합을 이용하여 산양(Nemorhaedus caudatus)의 서식지적합성모형을 개발하여 멸종 위기종의 서식지를 관리하기 위한 정보를 제공하는 것이다. 산양의 서식지적합성모형 개발을 위한 본 연구의 주요내용은 다음과 같다. 첫째, 산양 서식지 이용에 관한 기존 연구를 바탕으로 산양의 잠재적 서식지 환경변수를 분류하였으며, 분석 대상지의 산양 흔적 조사를 통해 서식지 환경변수의 재분류 및 x²검정(Chi-square test)을 통한 변수들의 유용성을 파악하고, 쌍체비교를 통한 환경변수별 가중치를 계산하였다. 둘째, 기존 부울논리(boolean logic)의 단점을 보완하기 위해 현장 조사의 결과를 바탕으로 퍼지논리(fuzzy logic)에 의한 산양 서식지의 각 환경변수별 주제도를 작성하고, 주제도들의 상관관계를 분석하여 상호 관련성이 높은 변수들의 중복을 피하였다. 셋째, 환경변수별 주제도와 변수별 가중치를 바탕으로 다기준평가기법(MCE, Multi-Criteria Evaluation)을 이용하여 분석대상지의 산양 서식지적합성모형을 개발하였다. 마지막으로, 개발된 서식지적합성모형의 타당성을 검증하기 위해 분석대상지 외부 지역을 대상으로 검증을 실시하였다. 분석 결과 분석대상지의 분류정확도는 서식가능성 0.5를 기준으로 93.94%의 매우 높은 분류정확도를 나타내었으며, 검증대상지에서는 95.74%의 분류정확도를 나타내어 본 모형의 분류정확도는 일관성이 높은 것으로 판단되었다. 또한 전체 공원구역에서 서식가능성 0.5이상의 면적은 59%를 차지하였다.퇴적이 우세한 것으로 관측되었다.보체계의 구축사업의 시각이 행정정보화, 생활정보화, 산업정보화 등 다양한 분야와 결합하여 보다 큰 시너지 효과와 사용자 중심의 서비스 개선을 창출할 수 있는 기반을 제공할 것을 기대해 본다.. 이상의 결과를 종합해볼 때, ${\beta}$-glucan은 고용량일 때 직접적으로 또는 $IFN-{\gamma}$ 존재시에는 저용량에서도 복강 큰 포식세로를 활성화시킬 뿐 아니라, 탐식효율도 높임으로써 면역기능을 증진 시키는 것으로 나타났고, 그 효과는 crude ${\beta}$-glucan의 추출조건에 따라 달라지는 것을 알 수 있었다.eveloped. Design concepts and control methods of a new crane will be introduced in this paper.and momentum balance was applied to the fluid field of bundle. while the movement of′ individual material was taken into account. The constitutive model relating the surface force and the deformation of bundle was introduced by considering a representative prodedure that stands for the bundle movement. Then a fundamental equations system could be simplified considering a steady state of the process. O

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.3-8
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• 2003

모든 SAR 영상에는 전자기파 간의 간섭으로 인한 스페클 잡영(speckle)이 존재하며, 이를 제거하는 것은 양질의 SAR 영상을 얻기 위한 필수적인 전처리 과정 중 하나라고 할 수 있다. 그러나 이러한 스페클 잡영을 제거하기 위하여 기존에 제안되었던 알고리즘은 잡영은 효과적으로 감소시키는 반면 경계선과 같은 영상의 고유 정보까지 함께 감소시키는 한계가 있었다. 따라서 본 연구에서는 SAR 영상의 경계선은 보존시키면서 영상으로부터 불필요한 잡영을 제거할 수 있는 알고리즘을 구현하고, 기존의 알고리즘과 비교하여 그 효율성을 평가하고자 한다. 영상의 통계적 특성에 근거하는 기존의 알고리즘과는 달리 웨이블렛 변환(Wavelet transform)으로 경계선 및 특징 정보의 여부를 판별한 후 평균 필터(mean filter)를 적용하는 경계선 보존(edge sharpening) 알고리즘은 경계 정보의 신뢰성을 향상시킬 수 있으며, 1차원 필터를 수평, 수직, 대각선, 역대각선 방향으로 적용함으로써 하나의 영상소를 중심으로 모든 방향에 대한 경계선 여부를 확인할 수 있는 장점이 있다. 본 연구에서는 512 × 512로 절취한 1-look SAR 영상에 대하여 창 크기 5 × 5의 경계선 보존 필터를 적용하고 동일영상에 대하여 기존의 Lee, Kuan, Frost 필터 등의 실험결과를 비교함으로써 그 적합성을 판단하고자 하였다. 실험결과에 대한 수치적인 평가는 ①정규화 평균을 이용하여 평균값의 보존 여부, ②편차 계수를 이용한 스페클 잡영의 제거 여부, ③경계선 보존지수(EPI)를 이용한 경계선의 보존 정도를 통해 이루어졌다. 본 연구의 실험결과를 통해 경계선 보존 필터는 평균값의 보존 여부 및 스페클 잡영 제거 정도에 있어 다른 필터들과 큰 차이가 없지만 경계선보존지수는 다른 필터들에 비하여 가장 우수함을 확인할 수 있었다.rbon 탐식효율을 조사한 결과 B, D 및 E 분획에서 유의적인 효과를 나타내었다. 이상의 결과를 종합해볼 때, ${\beta}$-glucan은 고용량일 때 직접적으로 또는 $IFN-{\gamma}$ 존재시에는 저용량에서도 복강 큰 포식세로를 활성화시킬 뿐 아니라, 탐식효율도 높임으로써 면역기능을 증진 시키는 것으로 나타났고, 그 효과는 crude ${\beta}$-glucan의 추출조건에 따라 달라지는 것을 알 수 있었다.eveloped. Design concepts and control methods of a new crane will be introduced in this paper.and momentum balance was applied to the fluid field of bundle. while the movement of′ individual material was taken into account. The constitutive model relating the surface force and the deformation of bundle was introduced by considering a representative prodedure that stands for the bundle movement. Then a fundamental equations system could be simplified considering a steady state of the process. On the basis of the simplified model, the simulation was performed and the results could be confirmed by the experiments under various conditions.뢰, 결속 등 다차원

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.247-255
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• 2003

80년대 초 GIS의 개념이 국내에 도입된 후, 1988년 대구광역시를 필두로 지자체의 GIS 구축이 시작되어 국가에서는 GIS 구축의 체계적인 관리의 필요성에 따라 1995년 제1차 국가GIS 기본계획을 수립하고, 2000년 ‘국가지리정보체계의 구축 및 활용 등에 관한 법률’을 제정, 공포하여 각 지자체의 실정에 맞는 GIS 기본계획을 수립하도록 유도하고 있다. 그러나, 바람직한 지자체 GIS 기본계획 작성의 표준이 제시되지 않아 지자체 GIS 기본계획이 개인의 안목이나 타 지자체의 내용을 참조로 만들어져 형식적이고 획일적인 결과물이 산출되고 있다. 그리하여 기존에 수립된 지자체 GIS 기본계획이 일부의 지자체를 제외하고는 해당 지자체의 GIS 구축 사업에 활용되지 못하고 책장속의 책으로 존재하고 있다. 따라서, 본 논문의 목적은 지자체 GIS 기본계획 표준안을 제시하여 향후 해당 지자체에서 GIS 기본계획을 수립할 때, 구성적인 측면의 틀을 제공하여 일정수준을 만족할 수 있는 지자체 GIS 기본계획의 수립을 지원하고자 한다. 지자체 GIS 기본계획 표준(안)을 도출하기 위해서 정보화전략계획과 해외 관련 연구, 국가GIS 기본계획의 검토를 통하여 지자체 GIS 기본계획의 구성요소를 도출하고, 기존지자체 GIS 기본계획의 목차를 중심으로 분석하여, 문제점을 도출하고, 그에 따른 시사점을 제시하여 지자체 GIS 기본계획 표준(안)의 기반이 되도록 하였다. 제안된 지자체 GIS 기본계획 표준(안)은 향후 각 지자체의 활용가치가 높은 GIS 기본 계획의 수립에 도움이 될 수 있도록 하며, 나아가서는 수립된 지자체 GIS 기본계획이 지자체의 성공적인 GIS 구축을 유도하는 가이드의 역할을 수행할 것으로 기대된다.가 있다. 본 연구의 결과를 통해 지방자치단체 GIS 기본계획에 있어 조직 측면의 장기적 비전의 제시가 가능하며 이를 통해 보다 성숙된 GIS 사업의 추진과 효율적인 시스템의 운영이 가능할 것이다.. 이상의 결과를 종합해볼 때, ${\beta}$-glucan은 고용량일 때 직접적으로 또는 $IFN-{\gamma}$ 존재시에는 저용량에서도 복강 큰 포식세로를 활성화시킬 뿐 아니라, 탐식효율도 높임으로써 면역기능을 증진 시키는 것으로 나타났고, 그 효과는 crude ${\beta}$-glucan의 추출조건에 따라 달라지는 것을 알 수 있었다.eveloped. Design concepts and control methods of a new crane will be introduced in this paper.and momentum balance was applied to the fluid field of bundle. while the movement of′ individual material was taken into account. The constitutive model relating the surface force and the deformation of bundle was introduced by considering a representative prodedure that stands for the bundle movement. Then a fundamental equations system could be simplified considering a steady state of the process. On the basis of the simplifie