• Korean Journal of Construction Engineering and Management
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• v.18 no.2
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• pp.58-70
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• 2017

The planning for material lifting operations is one of the key processes in high-rise building construction. Several previous studies have used rough calculations by referring to existing practices or establishing a target value for lifting cycle time or operating rate. Therefore, the purpose of this study is to propose a material lifting process optimization method for reducing the lifting cycle time and increasing the operating rate. In this study, we improve the cyclic operation network (CYCLONE) modeling method that considers the duration and zone information of each work task. This method can be used to hand over work tasks to another crew group in the work process. According to this methodology, this study optimizes the material lifting process, performs a sensitivity analysis, and evaluates the field applicability of the proposed material lifting process optimization method. Therefore, the optimized process was then applied to a high-rise building construction site. The lifting work process time and operating rate for the simulated as - is lifting process data, optimized process data, and field application result data were compared for each lifting height. From this comparison, the effectiveness of the optimization methodology was confirmed.

• Korean Journal of Environment and Ecology
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• v.32 no.5
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• pp.532-540
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• 2018

Importance-performance analysis (IPA) is a simple and effective technique that can assist practitioners in prioritizing customer attributes to enhance service quality and visitor's satisfaction. The purpose of this study is to use the IPA-Kano model to examine the correlation of visitor's satisfaction and management matters and deduce the management priority. It classifies 14 visiting satisfaction attributes into basic factors (forest environments and staff/information center), performance factors (the natural landscape, trail facilities, forest status, easy access, and historical and cultural resources), and excitement factors (the value of natural monument, educational experiences, and entrance fee) to select the management priority according to the achievement (satisfaction). The management priority according to the performance is staff/information center > easy access > forest environment > trail facilities, historical and cultural resources, forest status, and natural landscape > entrance fee and educational experience > value of natural monument. By considering their performance, it further identifies development priorities for visitor's satisfaction improvement. These priorities allow local governments to deploy scarce resources to improve satisfaction.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.7
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• pp.619-628
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• 2000

Abstract Perspective views provide a powerful depth cue and thus aid the interpretation of complicated images. The main drawback of current perspective volume rendering is the long execution time. In this paper, we present an efficient perspective volume rendering algorithm based on coherency between rays. Two sets of templates are built for the rays cast from horizontal and vertical scanlines in the intermediate image which is parallel to one of volume faces. Each sample along a ray is calculated by interpolating neighboring voxels with the pre-computed weights in the templates. We also solve the problem of uneven sampling rate due to perspective ray divergence by building more templates for the regions far away from a viewpoint. Since our algorithm operates in object-order, it can avoid redundant access to each voxel and exploit spatial data coherency by using run-length encoded volume. Experimental results show that the use of templates and the object-order processing with run-length encoded volume provide speedups, compared to the other approaches. Additionally, the image quality of our algorithm improves by solving uneven sampling rate due to perspective ray di vergence.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2001.11a
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• pp.28-28
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• 2001

$Bi_2Te_3$계 열전반도체 재료는 200 ~ 400K 정도의 저온에서 에너지 변환 효율이 가장 높은 재료로서 열전냉각 및 발전재료로 제조볍 및 특성에 관한 많은 연구가 진행되어 왔다. 전자냉각 모듈의 제조에는 P형 및 N형 $Bi_2Te_3$계 단결정이 주로 사용되고 있으나. $Bi_2Te_3$ 단결정은 C축에 수직한 벽개면을 따라 균열이 쉽게 전파하기 때문에 소자 가공사 수윤 저하가 가장 큰 문제점으로 지적되고 있다. 이에 따라 최근 열전재료의 가공방법에 따른 회수율 증가 및 열전특성 향상에 관한 열간압출, 단조와 같은 연구가 활발히 이루어지고 있다. 본 연구는 가스분사법(gas atomizer)을 이용하여 용질원자 편석의 감소, 고용도의 증가,균일고용체 형성, 결정립미세화 둥 급속응고의 장점을 이용하여 화학적으로 균질한$Bi_2Te_3$계 열전재료 분말을 제조하고, 제조된 분발을 압출가공하여 기계적성질, 소자의 가공성 및 열전 성능 지수율 향상시키는데 연구 목적이 있다. 본 설험에서는 99.9%이상의 고순도 Bi. Te. Se. Sb를 이용하여, 고주파 유도로에서 Ar 분위기로 용융하고, 가스분사법를 이용하여 균질한 $Bi_2Te_3$계 열전재료 분만을 제조하였다. 분말표면의 산화막을 제거하기 위하여 수소분위기에서 환원처리를 행하였고, 된 분말을 Al 캔 주입하여 냉간성형 한 후 진공중에서 압출온도를 변화시켜 열간압출 가공을 행하였다. 압출 온도변화에 따른 압출재의 미세조직 및 열전특성에 중요한 영향을 미치는 C면 배향에 대한 결정방위 해석, 압출재의 압축강도 등을 분석하였으며, 압출온도에 따삼 미세조직 변화와 결정방위의 변화에 따른 열전특성의 관계를 해석하였다성시켰고 이들이 산인 HNO3에서 녹았기 때문이다. 본 연구에서 개발된 새로운 에칭 용액인 90H2O2 - 10HNO3 (vol%)의 에칭 원리가 똑같이 적용 가능한 다른 종류의 초경 합금에서도 사용이 가능할 것으로 판단된다.로 판단된다.멸과정은 다음과 같다. 출발물질인 123 분말이 211과 액상으로 분해될 때 산소가스가 배출되며, 이로 인해 액상에서 구형의 기공이 생성된다. 이들 중 일부는 액상으로 채워져 소멸되나, 나머지는 그대로 남는다. 특히, 시편 중앙에 서는 수십-수백 마이크론 크기의 커다란 기공이 다수 관찰된는데, 이는 기공의 합체로 만들어진 것이다. 포정반응 열처리 시 기공 소멸로 만들어진 액상포켓들은 주변 211 입자와 반응하여 123 영역으로 변한다. 이곳은 다른 지역과 비교하여 211 밀도 가 낮기 때문에, 미반응 액상이 남거나 211 밀도가 낮은 123 영역이 된다. 액상으로 채워지지 못한 구형의 기공들 중 다수가 123 결정 내로 포획되며, 그 형상은 액상/ 기공/고상 계면에너지에 의해 결정된다.단의 경우, 파단면이 매끄럽고 파변상의 결정립도 매우 미세하였으며, 산확물 의 용집도 찾아보기 어려웠 나, 접합부 파단의 경우에는 파변의 굴곡이 비교척 심하고 연성 입계파괴의 형태를 보였￡며, 결정립도 모채부 파단의 경우에 비해 조대하였다. 조대하였다. 셋째, 주상기간 중 총 에너지 유입률 지수와 $Dst_{min}$ 사이에 높은 상관관계가 확인되었다. 특히 환전류를 구성하는 주요 입자의 에너지 영역(75~l13keV)에서 가장 높은(0.80) 상관계수를 기록했다. 넷째, 회복기 중에 일어나는 입자들의 유입은 자기폭풍의 지속시간을 연장시키는 경향을 보이며 큰 자기폭풍일수록 현저했다. 주상에서 관측된 이러한 특성은 서브스톰 확장기 활동이 자기폭풍의

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.440-446
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• 2020

This article highlights the issues and problems in the revised National Sports Promotion Act, Article 11(Fostering of certified sports leaders) and Article 11-2(Designation, etc. of qualifying examination institutions and training institutions) that were amended by Presidential decrees and Ordinances of the Ministry to implement the acts, July. 4, 2014. The national certification that was introduced to promote job career and to effectively manage human resource is forming a strong link with the education and labor market. Given the numerous human resources majoring in sports and exercise of the higher education and as they are providing them with professionalization of curriculum and instruction in higher education, the national sports promotion act administrative legislation article 8-2(offering certification for any person aged over 18 years old) should be omitted. The national sports promotion act administrative legislation article 12(Training course) that requires 90 hours of professional development should be revised to a few hours of continuing professional development every year.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.8
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• pp.918-929
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• 1999

동기식 스트림 암호통신 방식을 사용하는 암호통신에서는 암/복호화 과정 수행시 암호통신 과정에서 발생하는 사이클슬립으로 인해 키수열의 동기이탈 현상이 발생되고 이로 인해 오복호된 데이타를 얻게된다. 이러한 위험성을 감소하기 위한 방안으로 현재까지 암호문에 동기신호와 세션키를 주기적으로 삽입하여 동기를 이루는 주기적인 동기암호 통신방식을 사용하여 왔다. 본 논문에서는 CDMA(Cellular Division Multiple Access) 이동망에서 데이타서비스를 제공할 때 사용되는 점대점 프로토콜의 주소영역의 특성을 이용하여 단위 측정시간 동안 측정된 주소비트 정보와 플래그 패턴의 수신률을 이용하여 문턱 값보다 작은경우 동기신호와 세션키를 전송하는 비주기적인 동기방식을 사용하므로써 종래의 주기적인 동기방식으로 인한 전송효율성 저하와 주기적인 상이한 세션키 발생 및 다음 주기까지의 동기이탈 상태의 지속으로 인한 오류확산 등의 단점을 해결하였다. 제안된 알고리즘을 링크계층의 점대점 프로토콜(Point to Point Protocol)을 사용하는 CDMA 이동망에서 동기식 스트림 암호 통신방식에 적용시 동기이탈율 10-7의 환경에서 주기가 1sec인 주기적인 동기방식에서 요구되는 6.45x107비트에 비해 3.84x105비트가 소요됨으로써 전송율측면에서의 성능향상과 오복호율과 오복호 데이타 비트측면에서 성능향상을 얻었다. Abstract In the cipher system using the synchronous stream cipher system, encryption / decryption cause the synchronization loss (of key arrangement) by cycle slip, then it makes incorrect decrypted data. To lessen the risk, we have used a periodic synchronous cipher system which achieve synchronization at fixed timesteps by inserting synchronization signal and session key. In this paper, we solved the problem(fault) like the transfer efficiency drops by a periodic synchronous method, the periodic generations of different session key, and the incorrectness increases by continuing synchronization loss in next time step. They are achieved by the transfer of a non-periodic synchronous signal which carries synchronous signal and session key when it is less than the threshold value, analyzing the address field of point-to-point protocol, using the receiving rate of address bits information and flag patterns in the decision duration, in providing data services by CDMA mobile network. When the proposed algorithm is applied to the synchronous stream cipher system using point-to-point protocol, which is used data link level in CDMA mobile network, it has advanced the result in Rerror and Derror and in transmission rate, by the use of 3.84$\times$105bits, not 6.45$\times$107bits required in periodic synchronous method, having lsec time step, in slip rate 10-7.

• Journal of Broadcast Engineering
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• v.25 no.3
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• pp.346-352
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• 2020

Versatile Video Coding (VVC), a next-generation video coding standard that is in the final stage of standardization, has adopted various techniques to achieve more than twice the compression performance of HEVC (High-Efficiency Video Coding). VVC adopted Bi-prediction with CU-level Weight (BCW), which generates the final prediction signal with the weighted combination of bi-predictions with various weights, to enhance the performance of the bi-predictive inter prediction. The syntax element of the BCW index is adaptively coded according to the value of NoBackwardPredFlag which indicates if there is no future picture in the display order among the reference pictures. Such syntax structure for signaling the BCW index could violate the flexibility of video codec and cause the dependency issue at the stage of bitstream parsing. To address these issues, this paper proposes an efficient BCW weight signaling method which enables all weights and parsing without any condition check. The performance of the proposed method was evaluated with various weight searching methods in the encoder. The experimental results show that the proposed method gives negligible BD-rate losses and minor gains for 3 weights searching and 5 weights searching, respectively, while resolving the issues.

• Management & Information Systems Review
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• v.37 no.2
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• pp.259-281
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• 2018

Advocates of mandatory IFRS adoption claim that IFRS increase financial statement comparability, which in turn leads to greater cross-border investment(Securities and Exchange Commision, 2008). The notion is that improved financial statement comparability reduces the information acquisition costs of global investors and thereby increase their investment in foreign firms. The purpose of this study is to examine this assertion by examining whether the K-IFRS adoption rusults in improved comparability that leads to increased investment by foreign investment. We also examined whether the relation between comparability and foreign investment has strengthen after adoption of K-IFRS. To achieve the purpose of our study, we measure Korean firms comparability using stock price model, stock return model and cash flow from operation model by Barth et al.(2012). We use both foreign ownership in the end of year and average during the year for dependent variables were to reduce bias. We test our hypothesis using 1,817 firm-year observation of KOSPI firms during the period of our analysis, 2011-2015. Consistent with our hypothesis, we find K-IFRS adoption results in a greater increase in foreign investment in firms with high comparability firms. This result indicate that the adoption of K-IFRS intends to achieve the international accounting convergence as stated in the roadmap and to reduce the Korea Discount.

• Journal of Food Hygiene and Safety
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• v.17 no.1
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• pp.45-54
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• 2002

Hazard Analysis Critical Control Point System (HACCP) is recognized worldwide as a science-based and systematic approach for food safety. This has been initiated to establish the HACCP system in Korean slaughterhouses by suggesting some of effective implementation ways. An awareness level survey using questionnaire for 124 owners and 363 employees of the slaughterhouses, and 170 government officers responsible for HACCP duties was performed. This study shows that only 34.7% of owners, 21.1% of employees, and 57.1% of government officers have good understanding of HACCP, but 93.5%, 88.9% and 93.6% respectively have the willingness of HACCP implementation. Major benefits in HACCP implementation in the slaughterhouse raised by respondents were improvement of hygiene level of the plant (54.1%), increase of meat sale (17.6%), pride of the production of safe meat for human consumption (9.6%) and increase of meat export (7.5%), while major obstacles were financial difficulties (33.2%), poor levels of the facilities and equipments in the plants (27.3%), poor level of personal hygiene (19.4%), and lack of understanding of HACCP (12.3%). The most urgent measures which respondents raised to implement HACCP system effectively in the slaughterhouses at the moment were the Improvement of levels of facilities and equipments in the plants (36.6%), the establishment of HACCP base through education and training (19%), special benefits to HACCP implementing plant (11.8%), and close relationship between government and the industry (10.3%). The present study shows some of effective ways to implement HACCP in slaughterhouses.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.433-439
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• 2020

This study, which was designed to improve and increase the utilization of female elk, examined the possibility of collecting their embryos during the non-reproductive period using ultrasound-guided Ovum Pick-Up (OPU) technology. Once follicles in the ovaries of an elk were observed, the embryos were retrieved through the absorption of the follicles using an OPU ultrasound probe. Fifty-seven embryos were retrieved from 85 follicles, giving a retrieval rate of 67.1%. Morphological evaluation of the recovered embryos revealed 14.0% embryos to be in grade A, 19.2% in grade B, 15.7% in grade C, and 50.8% in grade D. The developmental efficiency of the retrieved embryos was also investigated using in vitro maturation, in vitro fertilization, and in vitro culture. After cultivating 28 embryos through in vitro fertilization, 19 embryos were found to be fertilized; the fertilization rate was 67.9%. Four embryos developed to the blastocyst stage, indicating a 14.3% development rate. This study confirmed that the production of fertilized embryos from a seasonal breeder, such as elk, is possible via the ultrasound-guided OPU method. If the efficiency of in vitro fertilization and in vitro culture can be improved through further research, it will help improve the efficiency of elk embryo production through the transplantation of their fertilized embryos.