• 한국통신학회논문지
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• 제39C권9호
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• pp.811-819
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• 2014

상황 인식은 유비쿼터스컴퓨팅 환경에 대한 진화를 변화시켰고 무선 센서네트워크 기술은 많은 응용기기에 대한 새로운 방법을 제시하였다. 특히, 행동 인식은 사람의 응용서비스를 제공하는데 있어 특정 사용자의 상황을 인식하는 핵심 요소로 의학, 취미, 군사 분야에서 폭넓은 응용분야를 갖고 있고 사용반경의 확대에서도 효율과 정확도를 높이는 방법에 크게 기여한다. 스마트폰 센서로부터 나오는 데이터로부터 프레임이 512인셈플 데이터를 얻어, 프레임간50%의 오버랩을 갖도록 하고 Machine Learning Algorithm 인 WEKA Experimenter (University of Waikato, Version 3.6.10)을 써서 데이더로부터 시간영역 특징값을 추출함으로써 행동 인식에 대한 99.33%의 정확도를 얻을 수 있었다. 또한, WEKA Experimenter의 사용기법인 C4.5 Decision Tree과 다른 방법인 BN, NB, SMO or Logistic Regression간의 비교실험을 하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권2호
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• pp.723-731
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• 2016

Background: Cancer is a major public health problem in many parts of the world. Gastrointestinal (GI) cancers are responsible for 20% of all cancer-related deaths. In Turkey, stomach cancers account for 8.9%, colon cancer for 6.9%, and pancreatic cancer for 5.9%. This study examined the anxiety-depression levels and the quality of life of patients with GI cancer. Materials and Methods: This descriptive study was carried out on 335 adult patients who had gastrointestinal cancer and who were hospitalized in medical oncology clinics. Data were collected by using hospital anxiety and depression scale, EORTC QLQ C-30 and a patient information form. Results: Patients who were male and secondary school graduates/graduates/postgraduates experienced more functional difficulties. Patients with poor economic status experienced more symptoms. Patient general wellbeing decreased with increase disease duration. The level of functional difficulties decreased with an increasing number of hospital stays. Anxiety scores increased with decreasing age. Both anxiety and depression scores increased with increasing disease duration. Patients who were female, single/widowed/divorced, and literate/elementary school graduates had higher anxiety and depression scores. Life quality decreased with increasing anxiety and depression. Conclusions: Patients should be supported to prevent anxiety and depression, and should be followed up with this in mind.

• 한국전자거래학회지
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• 제7권1호
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• pp.153-166
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• 2002

Nowadays an information exchange on Bn such as B2B electronic commerce is spreading. Therefore the systematic and stable management mechanism for storing the exchanged information is needed. For this goal there are many research activities for connection between XML application and relational database. But because XML data have hierarchical structures and relational database can store only flat-structured data, we need to store XML data in object-relational database that support hierarchical structure. Accordingly the modeling methodology for storing XML data in object-relational database is needed. In order to build good quality application systems, modeling is an important first step. In 1997, the OMG adopted the UML as its standard modeling language. Since industry has warmly embraced UML its popularity should become more important in the future. So a design methodology based on UML is need to develop efficiently XML applications. In this paper, we propose a unified design methodology for In applications based on object-relational database using In. To this goal, first we introduce a XML modeling methodology to design W3C XML schema using UML and second we propose data modeling methodology for object-relational database schema to store efficiently XML data in object-relational databases.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.170-173
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• 2009

In this paper, we propose a fast intra prediction mode selection method in Scalable Video Coding(SVC) which is an emerging video coding standard as an extension of H.264/Advanced Video Coding(H.264/AVC). The proposed method decides a candidate intra prediction mode based on the characteristic of macroblock smoothness. Statistical analysis is applied to computing that smoothness in spatial enhancement layer. We also propose an early termination scheme for Intra_BL mode decision where the RD cost value of Intra_BL is utilized. Compared with JSVM software, our scheme can reduce about 55% of the computation complexity of intra prediction on average, while the performance degradation is negligible; For low QP values, the average PSNR loss is very negligible, equivalently the bit rate increases by 0.01%. For high QP values, the average PSNR loss is less than 0.01dB, which equals to 0.25% increase in bitrate on average.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2002년도 금형가공 심포지엄
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• pp.231-238
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• 2002

미세 절삭에 의한 마이크로 형상가공 및 이를 이용한 미세금형 가공기술개발을 위하여 절삭 공구를 이용한 기계적 미세 가공법에 대한 고찰과 더불어 shaping, end-milling, drilling 등의 가공이 가능한 기계적 미세 가공시스템을 구성하고 이를 이용한 미세 치형 그루브와 미세 격벽 등 미세 형상 구조의 금형 개발을 위한 가공실험을 수행하였다. 본 실험에서는 먼저 shaping 방식으로 세 종류의 다이아몬드 바이트를 사용하여 알루미늄, PMMA, Nickel, 황동 등의 소재에 pitch $150{\mu}m$, 높이 $8{\mu}m$ 내외의 미세 치형의 금형 코어를 가공하였고, 다음으로 Z축에 air spindle을 설치하여 $\phi0.2mm$의 end-mill(WC)을 사용하여 황동 소재에 깊이 $200{\mu}m$, 폭 $200{\mu}m,\;100{\mu}m,\;50{\mu}m,\;30{\mu}m$의 두께 변화를 주어 미세 격벽에 대한 가공실험을 하였다. 미세 구멍가공실험으로는 drilling 전용장비를 구성하여 $\phi0.6\~0.15mm$의 drill공구로 SM45C와 세라믹$(Si_3N_4-BN)$ 소재에 스텝이송방식에 의한 미세 구멍 가공 실험을 실시하였다.

• 한국표면공학회지
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• 제29권5호
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• pp.371-378
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• 1996

An RF inductively coupled plasma (ICP) torch has been developed as a typical thermal plasma generator and reactor. It has been applied to various materials processings such as plasma flash evaporation, thermal plasma CVD, plasma spraying, and plasma waste disposal. The RF ICP reactor has been generally operated under one atmospheric pressure. Lately the characteristics of low pressure RF ICP is attracting a great deal of attention in the field of plasma application. In our researches of RF plasma applications, low pressure RF ICP is mainly used. In many cases, the plasma generated by the ICP torch under low pressure seems to be rather capacitive, but high density ICP can be easily generated by our RF plasma torch with 3 turns coil and a suitable maching circuiit, using 13.56 MHz RF generator. Plasma surface modification (surface hardening by plasma nitriding and plasma carbo-nitriding), plasma synthesis of AIN, and plasma CVD of BN, B-C-N compound and diamond were practiced by using low pressure RF plasma, and the effects of negative and positive bias voltage impression to the substrate on surface modification and CVD were investigated in details. Only a part of the interesting results obtained is reported in this paper.

• Nuclear Engineering and Technology
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• 제49권3호
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• pp.517-524
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• 2017

Cyber security is an important issue in the field of nuclear engineering because nuclear facilities use digital equipment and digital systems that can lead to serious hazards in the event of an accident. Regulatory agencies worldwide have announced guidelines for cyber security related to nuclear issues, including U.S. NRC Regulatory Guide 5.71. It is important to evaluate cyber security risk in accordance with these regulatory guides. In this study, we propose a cyber security risk evaluation model for nuclear instrumentation and control systems using a Bayesian network and event trees. As it is difficult to perform penetration tests on the systems, the evaluation model can inform research on cyber threats to cyber security systems for nuclear facilities through the use of prior and posterior information and backpropagation calculations. Furthermore, we suggest a methodology for the application of analytical results from the Bayesian network model to an event tree model, which is a probabilistic safety assessment method. The proposed method will provide insight into safety and cyber security risks.

• Design & Manufacturing
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• 제17권1호
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• pp.33-39
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• 2023

The ball end mill is a type of cutting tool that is widely used to process complex mold shapes including aspheric surfaces. Unlike the flat end mill in which the cutting edge is formed on the cylindrical handle, the cutting edge is formed from the cylindrical handle to the hemispherical shape, which is advantageous for processing curved shapes. However, since the cutting speed continuously changes during machining due to the helix angle of the cutting edge or the machining inclination angle, it is difficult to obtain a precise machined surface. Therefore, in this paper, machining was performed while changing the helix angle of the ball end mill and the angle of the machining slope under the same cutting conditions for STD 11 material, which is widely used as a mold material. Through this, the effect of the two variables on the roughness of the machined surface was analyzed. As a result, if the helix angle was 0 degrees, it showed the best surface roughness of Ra. 0.16 ㎛. When the helix angle was 20 degrees, the best surface roughness of Ra. 0.18 ㎛ was occurred.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제14회 학술발표회 논문개요집
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• pp.24-24
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• 1998

반도체장비를 포함하는 초고진공장비의 園훌化가 급속히 그리고 절실히 요구되고 있는 것이 현실정이다. 當面해서 실현할 국산진공장비의 대상은 廣範圍하다. 즉, 각종 진공 pump ( (rotary, dry, diffusion, cryo, ion, turbo melecular pump), 진공 chamber, 진공 line, gate valve 를 위 시 한 진공 V머ve, flange, gasket, fl않d야lU, mainpulater 퉁 진공 部品이 다. 진공계 의 핵심 은 適切하고 優良한 진공재료의 선태파 사용이다. 진공장비는 사용자가 원하는 진공도를 원하 는 시간 동안 륨空度를 유지해 주어야 한다. 진공재료 선태의 기준사항은:(1) 기체의 透過성 (2) 薰했훌 (3) 혔體放出특성 - -outgassing과 degassing- (4) 機械的 량훌度 (5) 온도 의존성 (6) 化學톡성 (7) 加I성 및 鎔接 성 (8) 課電특성 (9) 磁氣특성 (10) 高速함子 및 放射線 특성 (11) 經濟성 및 調達생 둥이 다. 우량한 초고진공계재료는 풍부하게 개발되어 왔고, 또 新材料들이 개발되고 있다. 여기에서는 주로 초고진공 내지는 극고진공계의 構造材料, 機能材料, 部品材料 일반파 몇가지 신재료의 특 성에 관해서 記述한다. M Mild SteeHSAE, 1112, 1010, 1020, 1022, etc)., S Stainless SteeHAlSI, 304, 304L, 310, 316, 321, 347): 구조재료, chamber, fl하1ges A Aluminum과 Alloys (1060, 1100, 2014, 4032, 6(뻐1): 구조재료, chamber, flanges, gaskets A AI, Al 떠loy는 SS에 代替하는 역 할올 시 작하고 있다. C Copper, Copper Alloys(C11$\alpha$)0, C26800, C61400, Cl7200): 내장인자, gasket, cryopanel, tubing T Titanium, Ziriconium, Haf띠um 및 Alloys: 특히 Ti은 10n pump 용 getter material 이 외 에 U UHV,XHV용 chamber계로서 관심올 끌고 있다. N Nickel, Nickel Alloys (200, 204, 211, monel, nichrome): 부식 방지 , 전자장치 , 자기 장치 귀 금속(Ag, Au, Pt, Pd, Rh, Ir, Os, Ru): 보조부품, gasket, filament, coating, thermocouple, 접 합부위 T TiC, SiC, zrC, HfC, TaC 둥의 탄화물과, BN, TiN, AlN 동의 질화물, 붕화물이 둥장하고 었 다. 유리: Soda Lime, Borosilicate, Potash Soda Lead: View Port, Chamber envelope C Ceramics: AlZ03, BeO, MgO, zrOz, SiOz, MgOzSiOz, 3Alz032SiOz, Z$textsc{k}$hSiOz S상N4: e electrical, thermal insulators, crucibles, boats, single crystals, sepctr려 windows 저자는 최근 저자들이 발견한 Zr-Ti-Cu-Ni-Be amorphous alloys coated cham뾰r가 radiation p proof로 이용될 수 있는 사실을 점검하고 었다 .. Z.Y. Hua 들은 Cs3Sb를 새로운 photocathode 재료로 보고하고 있다.

• 한국환경복원기술학회지
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• 제19권1호
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• pp.13-23
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• 2016

This study was conducted to investigate the growth characteristics of warm-season turfgrasses and to find out suitable turfgrass species on Saemangeum reclaimed land. Twenty native zoysiagrass(Zoysia sinica, Z. matrella, Z. japonica, Medium-leaf type zoysiagrass(hybrid zoysiagrass)) and bermudagrass(Cynodon dactylon) collected from Korea were used in this study. Total stolon length and the number of stolon per square meter, relative growth rate of shoot and stolon, and coverage rate were analyzed for 2 year. C. dactylon showed not only the most growth response with high relative growth rate of shoot and stolon, which were 19.9% and 66.3%, but also resulted in higher level of turf visual quality compared to others. Whereas Z. japonica showed the least growth response with low relative growth rate of shoot and stolon, which were 2.4% and 0.7%. Although all warm-season turfgrasses took root and grew up well, there were different growth rates between the interspecies. Z. sinica 'Z2034', Z. matrella 'Z4091', Z. japonica 'Z1064', Medium-leaf type zoysiagrass 'ZN6019' and C. dactylon 'BN7014' were the greatest growth rate of shoot and stolon. These results will be useful for selecting salt tolerant breeding lines and also used to develop a turfgrass cultivar with strong salinity tolerance through continuous monitoring.