• Journal of the Korean Geophysical Society
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• v.7 no.4
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• pp.313-324
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• 2004

The finite element method and statistics of the convergence measurement are useful method of the stability analysis of the tunnel adjacent to the pier. It is the purpose of the this case study to certificate of validity of the application of those methods. The safety of the pilot tunnel method and LW pre-grouting has been evaluated from the FEM analysis. The three-dimensional finite element method is carried out for the decision of the level of stress redistribution at the two-dimensional numerical analysis. An analysis of the convergence is carried out by the estimation of preceding convergence at tunnel excavation. F-examination is applied for this estimation. As results of that analysis, The F-value is from 10.81 to 158.74 and the coefficient of determination is from 0.82 to 0.99. An analysis of convergence is carried out by using regression analysis. Consequently, it is shown that the convergence can be modeled as following function C(t) = a[1-exp(-bt)].

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.5
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• pp.899-908
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• 2021

Since the modern weapon system is composed of a complex system, it is quite difficult to derive the priority of performance improvement factors. In addition, research on the method for prioritizing quantitative performance improvement factors considering the opinions of stakeholders is insufficient. In this study, in order to quantitatively derive the priorities of performance improvement factors for K1 tanks and K2 tanks, a survey was conducted with experts with experience in tank development, and the preface data was analyzed using AHP, scoring method, and TOPSIS methods. As a result, priorities were quantitatively derived. The results of this study are expected to be used as decision-making indicators for stakeholders in the future weapon system development and performance improvement stage.

• Journal of KIISE:Software and Applications
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• v.35 no.6
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• pp.392-403
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• 2008

User reviews are valuable information that can be used for various purposes. In particular, the product reviews on online shopping sites are important information which can directly affect the purchasing decision of the customers. In this paper, we present our design and implementation of a system for summarizing the customer's opinion and the features of each product by analyzing reviews on a commercial shopping site. During the analysis process, several natural language processing(NLP) techniques and the semantic dictionary were used. The semantic dictionary contains vocabularies that are used to express product features and customer's opinions. And it was constructed in semi-automatic way with the help of the tool we implemented. Furthermore, we discuss how to handle the vocabularies that have different meanings according to the context. We analyzed 1796 reviews about 20 products of 2 categories collected from an actual shopping site and implemented a novel ranking system. We obtained 88.94% for precision and 47.92% for recall on extracting opinion expression, which means our system can be applicable for real use.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5403-5408
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• 2012

In this paper, we introduce the multiple frequency bio-electrical impedance analysis method for body composition analysis. And then we implement the multiple frequency bio-electrical impedance analysis system. Overall system consists of: multiple frequency alternating current signal generator contained alternating current signal, phase signal detector, voltage signal detector, micro controller, in-out device(key-pad LCD), conductivity electrodes, system power. We explain the architecture of the system and required theory to implement the system. In order to investigate the clinical significance of the body composition data, compare to the data measured by the expert body composition analyzer which provide high reproduction and precision. Finally, experimental results which are the correlation between the measured data show the very high reproduction performance of the body composition analysis in the proposed system.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.3
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• pp.85-91
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• 1999

$H:LiNbO_3$ optical modulator with Cu/parylene electrode layer, which has a merits in the bandwidth, power consumption and fabrication conditions as compared with conventional Au/Cr/$SiO_2$, is proposed and fabricated. Analysis and design of optical modulator is performed by finite element calculation. Various unit processes for fabricating the proposed modulator, 1550nm $H:LiNbO_3$ optical waveguide, parylene buffer layer, and CPW Cu electrode, were developed, After dicing and end-face polishing of fabricated modulator chip, optical modulation responses as sawtooth electrical driving voltage has been measured at low frequencies. Properties of optical waveguide had not been changed before and after Cu/parylene electrode processes, which make confirm the reproducible fabrication of optical modulator.

• Journal of Korea Water Resources Association
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• v.33 no.2
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• pp.195-205
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• 2000

Many types of factors were devised to calculate time of concentration. Singh(976) derived time of concentration of overland flow using kinematic wave theory for plane, converging, and diverging geometric configurations. The present paper investigated the time of concentration for particularly plane geometric configuration. A theoretical equation of time of concentration is derived based on the assumption of impervious overland flow as in the open channel flow. The study characterized the overland flow by many types of characteristic flow such as rough turbulent flow, smooth turbulent flow, laminar flow, and then suggested a theoretical equation on each flow condition. The present paper further considered the rainfall intensity as a main factor and devised an approximate composite equation reflecting the effect of rainfall intensity given at various return periods.

• Water for future
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• v.19 no.1
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• pp.75-86
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• 1986

This study aims at the analysis and application of PMP(Probable Maximum Precipitation)for the determination of design flood in the river basin planning and design of major hydraulic structures. PMP was estimated by hydro-meterological method statistical method and envelope curve method. PMF(Probable Maximum Flood)was then estimated from this PMP by synthetic unit hydrograph method and chow method. From the comparison of three methods for PMP estimation of magnitude of PMP in order of statistical, hydro-metrological, envelope curve method. Among PMP results estimated by each method it is believed that the hydro-meteorological method gave the best proper value in comparison with historical maximum rainfall because of this method reflected upon all meterological factor. From the comparison of PMP with probable rainfall and flood, it was shown that estimated value by statistical method and hydro-metrological method were nearly equivalent to the value of return period 100 years and its value of envelope curve method was equivalent to return period 200 to 500 year. It was found that PMF estimated from would be more safe for the design of major hydraulic structures in the consideration.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.93-93
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• 2012

섬유산업은 그 제조 스트림이 높은 오염 부하와 에너지 다소비를 특징으로 하여 환경규제에 따라 기존 시장의 위축 가능성이 상존하고 있다. 특히 섬유산업의 주요 스트림 중의 하나인 염색가공 공정은 섬유에서 불순물을 제거하고 심미한 색상과 사용 목적에 적합한 성능을 부여하는 단계로 섬유제조 공정에서 가장 높은 부가가치를 부여하는 단계이나 고온의 물과 다양한 화공약품을 많이 사용하고 그 처리온도가 비교적 높아($100^{\circ}C$ 이상) 대표적인 폐수 발생 공정이자 에너지 다소비 공정이다. 섬유의 염색 방법 중 반연속방법인 CPB(Cold Pad Batch)염색은 반응성 염료와 알칼리의 혼합액으로 구성된 염액에 원단을 패딩한 후 상온에서 수 시간 배칭하고 수세 및 후처리하여 염색하는 방법으로 작업공정관리, 설비관리가 간편하고 에너지소비량 절감, 높은 생산성의 장점이 있다. CPB염색법은 주로 직물에 적용되어 보편화 되었으며, 작업공정 중 장력의 영향을 많이 받는 니트 소재에 적용되는 사례는 드물다. 직물류의 CPB 염색가공법은 대구 경북을 중심으로 연구진행이 활발히 이루어지고 있어 국내 100대 정도의 CPB 관련 장비가 직물제품에 한정되어 가동되고 있는 반면, 니트 CPB 관련 염색 가공 업체는 1곳에 불과한 실정이나 니트류에 대한 지속적인 수요 증가를 고려하면 니트 소재에 대한 CPB염색 적용은 시의적절한 필수요소라고 판단된다. 니트 소재에 대한 CPB염색가공 적용 시 나타나는 문제점은 작업원단의 변부 말림현상 발생, 전폭 상태에서의 색상차이인 listing현상, 원단의 첫도입부분과 끝부분의 색상차이인 tailing현상이며, 반복되는 작업 시 염색재현성을 확보하는 것으로 나타난다. 본 연구에서는 CPB염색 시 CPB Head 장치의 Padding 방식 즉, trough와 Nip type에 따른 염색 시 알칼리와 염료 투입에 따른 염색 재현성(Build up, Ending, 알칼리 안정성)을 비교해 보았으며, 이에 따른 염색제품의 물성 및 견뢰도를 확인하여 보다 효율적인 방식을 선별하였다.

• Korean Journal of Cognitive Science
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• v.12 no.1_2
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• pp.35-42
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• 2001

In this paper. a document is represented as a weighted graph called a text relationship map. In the graph. a node represents a vector of nouns in a sentence, an edge completely connects other nodes. and a weight on the edge is a value of the similarity between two nodes. The similarity is based on the word overlap between the corresponding nodes. The importance of a node. called an aggregate similarity in this paper. is defined as the sum of weights on the links connecting it to other nodes on the map. In this paper. we present a Korean text summarization system using the aggregate similarity. To evaluate our system, we used two test collection, one collection (PAPER-InCon) consists of 100 papers in the field of computer science: the other collection (NEWS) is composed of 105 articles in the newspapers and had built by KOROlC. Under the compression rate of 20%. we achieved the recall of 46.6% (PAPER-InCon) and 30.5% (NEWS) and the precision of 76.9% (PAPER-InCon) and 42.3% (NEWS).

• Journal of Aerospace System Engineering
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• v.14 no.1
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• pp.16-20
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• 2020

The fatigue happening during the road riding of the vehicle and for the moment the aircraft lands on the runway is closely related to the life cycle of the landing gear, the airframe, the vehicle's suspension, etc. The multiple loads acting on the wheel are longitudinal, lateral, vertical, and braking forces. To study the dynamic characteristics and fatigue stiffness of the vehicle, the dynamic fatigue simulator generally has been used to represent the real road vibration in the lab. It can save time and cost. In hardware, the critical factor in the hydraulic fatigue simulator structure is to decouple each axis and to endure several load vibration. In this paper, the inverse kinematic analysis method derives the magnitude of movement of the hydraulic servo actuator by the coupling after rendering the maximum movement displacement in the axial direction at the center of the dummy wheel. The result of the analysis is that the coupling between the axes is weak to reproduce the real road vibrations precisely.