• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 학술대회지
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• pp.885-889
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• 2004

Fast and high-quality document clustering algorithms play an important role in providing data exploration by organizing large amounts of information into a small number of meaningful clusters. Hierarchical clustering improves the performance of retrieval and makes that users can understand easily. For outperforming of clustering, we implemented hierarchical structure with variety and readability, by careful selection of cluster topic words and deciding the number of clusters dynamically. It is important to select topic words because hierarchical clustering structure is summarizes result of searching. We made choice of noun word as a cluster topic word. The quality of topic words is increased $33\%$ as follows. As the topic word of each cluster, the only noun word is extracted for the top-level cluster and the used topic words for the children clusters were not reused.

• 한국생산제조학회지
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• 제19권1호
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• pp.94-100
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• 2010

Nowadays, several nontraditional machining(NTM) processes are widely used to machine a complex and accurate shape part of hard materials, such as titanium, ceramics, high strength temperature resistant and refractory materials which are difficult to machine and having high strength, hardness, toughness. Machining of these complex shapes in such materials by traditional machining processes are very difficult. The NTM processes is important in the areas of micro- and nano scale machining, where high accuracy and superior surface characteristics are required, which can only be achieved using these NTM processes. So, for effective selection of different NTM processes, careful decision making for a given NTM application is often necessary. An appropriate NTM process for a given material and shape condition is very difficult for the novice engineers. In this paper, an expert system based on an analytic network process(ANP) is suggested for a best selection of NTM process in a NTM application considering an prior interdependency effect among various factors.

• 한국중재학회지:중재연구
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• 제23권3호
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• pp.1-23
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• 2013

Form requirements particularly for arbitration clauses are widely perceived as an obstacle for efficiently resolving disputes on an international level. The paper discusses the recent suggestion that the freedom of form principle under Art. 11 CISG extended to arbitration, forum selection, or choice of law clauses in international sales contracts and thus superseded any and all formal requirements in this regard. After analysing national and international form requirements with regard to said clauses, the authors elaborate that while dispute clauses are indeed encompassed by the CISG's scope of application, freedom of form under the CISG was neither intended to nor should it apply to dispute clauses. This result is further confirmed by the interplay of the CISG with other international conventions, first and foremost the 1958 New York Convention, as well as a careful analysis of the so called most-favourable-law-approach.

• 대한치과의사협회지
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• 제56권9호
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• pp.492-502
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• 2018

Anterior maxillary teeth play an important role in determining a person's first impression and facial profile. Implant surgery in esthetic area requires more careful diagnosis, treatment planning, surgery, and prosthetic restoration than in posterior area. To avoid complications in surgery and prosthetic restoration for implants in esthetic area, accurate diagnosis and appropriate case selection become very important. If you have decided to restore the area with implant prosthesis, you have to know exactly where to place an implant. I will discuss the ideal implant position in terms of mesio-distally, apico-coronally, labio-palatally, and implant angulation. And I would like to point out the selection of fixture diameter & length for anterior implant. Finally, a clinical implant prosthesis case in maxillary central incisor will be shown. In conclusion, for superior esthetic outcome in anterior implant prostheses, we must understand the patient's anatomic condition and know our ability.

• 소음진동
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• 제5권2호
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• pp.163-168
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• 1995

A criterion for the selection of spindle motor speeds in a hard disk drive (HDD) is investigated to guarantee stability and reduce nonrepeatable runout of a spining disk. Since the natural frequencies of the spining disk and the forced frequencies generated from the spindle motor depend on the rotating speed, careful consideration should be taken to avoid the resonance between the disk and motor. To do this, the natural frequencies of the spining disk are calculated and they are compared with the forced frequencies from the spindle motor.

• 한국기계가공학회지
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• 제13권6호
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• pp.54-60
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• 2014

In industry, several casting process are widely used to manufacture complex and accurate blank part of hard materials such as aluminum, casting steels, bronze and magnesium alloys which are difficult to manufacture in a blank shape. Even if the casting process does not high accuracy superior surface characteristics other machining process, the casting process is widely used in manufacturing blank part. Furthermore, it is difficult to select appropriate casting process a part among several casting process. for effective selection different process, a careful decision given casting application is necessary. An appropriate casting for a given material and shape condition must be selected for novice engineers in industry. In this paper, an expert system based on an analytic network process(ANP) is suggested for best selection of casting considering a prior interdependency effect among various factors such as material, geometry, process capability, economy and equipment.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1390-1392
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• 2003

The arid regions of western China are currently the focus of extensive exploration and development. This paper reports on recent experience gained by Chinese and Canadian project team members in the use of a variety of Earth observation satellite imagery for oil exploration and environmental assessment exercises in the Kuche area of Xinjiang. Through careful archival data selection and more recent data acquisition schemes, we have established several time series of MODIS, Landsat and Radarsat imagery in order to obtain a better understanding for daily, seasonal as well as decadal changes of the natural environment as well as man-made environmental features.

• Journal of Korean Dental Science
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• 제15권2호
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• pp.112-120
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• 2022

In this article, the contemporary root canal treatment procedure using nickel-titanium (NiTi) instruments was reviewed to understand the correlations between the properties of files and safety of the clinical usage. Literatures were reviewed according to the process of clinical procedure of the root canal preparation, mainly for shaping during orifice flaring, glide-path preparation, and main canal instrumentation. Considering the reasons for NiTi file fracture, clinically implacable issues and ideas were discussed to reduce the fracture risk and increase clinical efficiency of the NiTi file systems. Various kinds of NiTi file systems have their own characteristics and properties given from their geometries and heat treatments and so on. Proper selection and careful usage of the NiTi file systems may reduce the risk of file fracture and increase the efficiency of NiTi file systems. Understanding of the clinical implications from the mechanical properties and characteristics of the engine driven NiTi instruments may decrease the risk of NiTi file fractures and increase the success rate in root canal treatment.

• 보존과학회지
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• 제26권1호
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• pp.43-60
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• 2010

이 연구에서는 송광사 사천왕상 소조토의 정량적이고 객관적인 제작기법을 규명하고, 원료 산지를 추정하여 보존처리시 동일한 재료로 복원할 수 있는 기초 자료를 확보하였다. 이 결과, 사천왕상의 제작에 사용된 소조토는 층위와 대상에 관계없이 성인적으로 거의 동일한 흙으로 확인되었다. 그러나 소조토가 상대적으로 두터운 부위에서는 초벌층과 마감층에서 입도와 유기물의 함량을 달리하였고, 두께가 얇은 부위는 층위의 구분 없이 한 종류의 흙만을 사용하였다. 또한 복원토는 사천왕상의 소조토와 성인적으로 아주 유사한 흙이 사용되었으며, 층위에 따라 정선도의 차이를 보였다. 원산지 해석 결과, 추정산지 일대 흙은 소조토와 동일기원으로 판명되어 보존처리용 재료로 적합할 것으로 판단된다. 이 결과는 소조사천왕상의 무기재료학적 연구 및 보존처리에 크게 기여를 할 것으로 사료된다.

• 대한원격탐사학회지
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• 제40권1호
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• pp.93-101
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• 2024

Accurate field crop classification is essential for various agricultural applications, yet existing methods face challenges due to diverse crop types and complex field conditions. This study aimed to address these issues by combining support vector machine (SVM) models with multi-seasonal unmanned aerial vehicle (UAV) images, texture information extracted from Gray Level Co-occurrence Matrix (GLCM), and RGB spectral data. Twelve high-resolution UAV image captures spanned March-October 2021, while field surveys on three dates provided ground truth data. We focused on data from August (-A), September (-S), and October (-O) images and trained four support vector classifier (SVC) models (SVC-A, SVC-S, SVC-O, SVC-AS) using visual bands and eight GLCM features. Farm maps provided by the Ministry of Agriculture, Food and Rural Affairs proved efficient for open-field crop identification and served as a reference for accuracy comparison. Our analysis showcased the significant impact of hyperparameter tuning (C and gamma) on SVM model performance, requiring careful optimization for each scenario. Importantly, we identified models exhibiting distinct high-accuracy zones, with SVC-O trained on October data achieving the highest overall and individual crop classification accuracy. This success likely stems from its ability to capture distinct texture information from mature crops.Incorporating GLCM features proved highly effective for all models,significantly boosting classification accuracy.Among these features, homogeneity, entropy, and correlation consistently demonstrated the most impactful contribution. However, balancing accuracy with computational efficiency and feature selection remains crucial for practical application. Performance analysis revealed that SVC-O achieved exceptional results in overall and individual crop classification, while soybeans and rice were consistently classified well by all models. Challenges were encountered with cabbage due to its early growth stage and low field cover density. The study demonstrates the potential of utilizing farm maps and GLCM features in conjunction with SVM models for accurate field crop classification. Careful parameter tuning and model selection based on specific scenarios are key for optimizing performance in real-world applications.