• International Journal of Computer Science & Network Security
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• 제23권5호
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• pp.121-127
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• 2023

A 500 km/h linear motor high speed terrestrial transportation service is planned to launch 2027 in Japan. In order to support 5G service in the train, the Sub-carrier spacing frequency of 30 kHz is planned to be used instead of common 15 kHz sub-carrier spacing to mitigate Doppler effect in such high-speed transportation. In addition, to increase the cell size of 5G mobile system, plural Base Station antenna will transmit the identical Down Link (DL) signal to form the expanded cell size along the train rail. In this situation, forward and backward antenna signals will be Doppler shifted by reverse direction respectively and the receiver in the train might suffer to estimate accurate Channel Transfer Function (CTF) for its demodulation. In this paper, Delay and Doppler Profiler (DDP) based Channel Estimator is proposed and it is successfully implemented in signal processing simulation system. Then the simulated performances are compared with the conventional Time domain linear interpolated estimator. According to the simulation results, QPSK modulation can be used even under severe channel condition such as 500 km/h, 2 path reverse Doppler Shift condition, although QPSK modulation can be used less than 200 km/h with conventional Channel estimator.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.597-598
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• 2015

In order to improve the reliability of cost estimation results using CBR, there has been a continuous issue on similarity measurement to accurately compute the distance among attributes and cases to retrieve the most similar singular or plural cases. However, these existing similarity measures have limitations in taking the covariance among attributes into consideration and reflecting the effects of covariance in computation of distances among attributes. To deal with this challenging issue, this research examines the weighted Mahalanobis distance based similarity measure applied to CBR cost estimation and carries out the comparative study on the existing distance measurement methods of CBR. To validate the suggest CBR cost model, leave-one-out cross validation (LOOCV) using two different sets of simulation data are carried out. Consequently, this research is expected to provide an analysis of covariance effects in similarity measurement and a basis for further research on the fundamentals of case retrieval.

• 무역학회지
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• 제45권1호
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• pp.119-135
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• 2020

It is well-known that if a claim for damage [Note: Damage can be singular or plural] is made based on a breach of contract, calculating the existence and magnitude of certain profits to be deducted based on the damage can be problematic. In the case of a time charter party, even if the early redelivering vessel by the time charterers constitutes a breach of contract, it is still not an exception. In particular, interest in the shipping business seems to be relatively high in terms of how claims for damage by ship owners have been adjusted. In the case of the New Flamenco, there is a debate over whether or not to deduct the difference between the sale price immediately after redelivering the ship and the sale price upon expiration of the contract from the damage based on the breach of contract for the early time charter redelivery vessel. This paper focuses on this case since it appears to be of practical importance and has implications on how to calculate the amount of damage in the case of cancellation for early redelivery vessel in a time charter party.

• 한국과학교육학회지
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• 제29권3호
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• pp.277-290
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• 2009

In the era of the outcome-based education, multiple-choice test has been widely employed owing to its efficiency that enables educators to evaluate a quantity of students with much objectiveness. However, the prevalent test has not been reconsidered enough to overcome its apparent shortcomings: examiners' effort for developing plausible and faultless distracters defending from every falsification, and students' random guessing on key choices. For alleviating such defects, tiered test as an experimental format of multiple-choice tests has been suggested in science education. Since there has not accumulated much study on the implementation of tiered tests, our research aim is set to construct a framework suggesting statistical indexes for rationally discerning tiered units that develop an effective tiered test. Graded both by our tiered-scoring and by the conventional partial-scoring, the preliminary tiered test in secondary physics attests the improvement in its discrimination and difficulty distribution. The findings reveal that the two indexes discern effective tiered items: discrimination increase (Ct-p) and difficulty decrease (Dp-t). Based on the index information, 4 heterogeneous tier types are recommended in the content of secondary physics: directional manipulation, repeated calculation, diverse explanation, and plural variables.

• 한국실내디자인학회논문집
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• 제22권6호
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• pp.162-172
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• 2013

This study focuses on the genealogical analysis of the urban public spaces by the local history of Seoul which is significantly different from western cities. The analysis targets the discourse of the urban street which defines urban space-structure among the urban public spaces. Based on the analysis, we define the progress levels of urban public design policy in Seoul. Firstly, in 1960's and 1970's, 'urban reconstruction' was intensively carried out for the country modernization, and 'vehicle preferred street expansion' resulted in damages to historical inheritance, in-humanized street, and cultural uniformity. 1980's and 1990's would be defined as 'politic acceptance of plural values to the urban street.' There were the Olympic Games held in Seoul in 1988, which were the celebrations of the 600th capital establishment and the autonomous local government system. In the meanwhile, diverse values on the urban street were discussed in terms of globalization. There also were the self-reflection for the urban skyscrapers and high-population rate, the cultural uniformity of urban street, and the commercialization in downtown with urban reconstruction plans. Then, the sense of landscape and amenity was focused. Various urban projects and regulations were held according to the changes of value recognition. 2000's can be defined as 'introduction to the organic integration and the urban public design governance.' In the 21st century, types of recognition have changed significantly, which include publicness, humanism, sustainability, symbolism, artistry, placeness, and communication. They cause the establishment of ordinances and the installation of integrated organization via urban design administration. The legislation has been revised in order to support the various methods for the maintenance and operation of urban landscape in terms of local characteristics. New regulations were established for residents to participate in the processes of the urban planning with street design policy.

• 한국콘텐츠학회논문지
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• 제20권11호
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• pp.15-27
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• 2020

문제해결이 중심인 디자인 과정에서 일반적으로 디자인 창의성의 저해요소는 2-3개가 동시에 발생하며 연계되어 어려움을 가중시킨다. 디자인 문제는 언제나 특이하고 독특하며 정의하기 힘든 난해한 상황에서 발생하므로 공식을 통한 정답도출은 가능하지 않으며 그 해답은 언제나 복수로 나타난다. 본 연구는 선행연구에서 논의된 디자인 창의성의 대표적인 저해요소에 대한 극복방법을 모색하는 후속연구로서 해결방안 제시와 그 효과성 입증을 목적으로 하고 있다. 이를 위해 선행연구에서 제시된 저해요소의 해결방안 모색과 핵심적인 해결팁(창의성 발전카드)을 고안하는 질적 연구를 수행하였다. 동시에 실험과 통계분석을 활용하는 양적 연구 방법론을 채택하였다. 창의성 발전카드를 활용하여 어떤 대상(원형)의 핵심특성을 파악한 후 핵심특성의 변형, 본질적 문제 재고, 의도적 차별화 등 원형의 환원적 분석을 활용해 창의적 해결방안에 효과적으로 접근할 수 있었다. 결과로써 제시된 해결방안은 디자인 창의성 저해요소의 극복방법으로서뿐만 아니라 창의성 향상에 효과적임을 확인하였다.

• 디지털융복합연구
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• 제16권9호
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• pp.383-390
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• 2018

본 연구의 목적은 가상성의 디지털 놀이 발전방향과 디지털 놀이 도구가 기존 놀이의 속성과 어떻게 결합되어 유형화되고 있는지 알아보는데 있다. 가상성 특성과 놀이론을 살펴보고 사례를 4가지 유형으로 도출하여 로제카이와의 4가지 놀이 속성으로 분석하였다. 분석결과 아곤의 경우 상호경쟁 대상이 단수와 복수, 컴퓨터 및 미래의 자신 등으로 확대되고 있다. 미미크리는 온-오프라인의 경계를 넘나들고 분절과 경계의 모호 양상을 보였다. 알레아는 즉시성과 동시성에 의한 우연 발생의 다양화가 강화되고 있다. 일링크스는 몰입의 극대화를 감각과 도구로 다양하게 적용하며 새로운 가상성 기술의 개발과 실험이 지속되고 있다. 결과적으로 다양한 융합적 결합에 의한 시공간의 확장성과 공존성 경향으로 놀이가 발전하고 있었다. 본 연구는 디지털 놀이 관련 연구와 디지털 놀이 기획개발에 도움이 되고자 하며 향후 가상성을 활용한 스토리 테마형 디지털 놀이터 기획설계에 관한 연구를 진행 예정이다.

• 대한간호학회지
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• 제1권1호
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• pp.103-110
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• 1970

It is important to point out that the percental mortality rate of the multiple pregnancy is almost twice of the single pregnancy due mainly to their prematurity and the mothers of twins will also be suffered from the plural births to nurse and take care of them. We therefore studied the incidence, the sex ratio, the types of deliveries, the complications and the percental mortality rate of the twin deliveries in order to promote the development of our field of maternal and child nursing. We selected our materials from the 112 patients who had been admitted and delivered twins in the department of OB. & Gyn. of the S.N.U. Hospital from Jan. 1962 to Dec. 1969. The abstructed results of this study were as follows. 1. The incidence of twins among 7, 731 births was 1:69 2. The occurrence of twins from elder multigravida was 4 to 6 times higher than younger primigravida mothers under 35 years of age. 3. The generational length of 45.5% of all twins was under 38 weeks and the mean birth weight of 1st and 2nd twins were 2, 354.7gm and 2, 215.8gm respectively. 4. The sex ratio of twins was 99 males and 124 females. 5. Presentation of twins: 59 cases (52.69%) were in both vertex. 37 cases (33.03%) in vertex plus breech. 15 cases (13.39%) in both breech and one case (0.89%) in transverse presentation. 6. For the types of deliveries Spontaneous deliveries were in 90 babies (40.6%) Breech extraction in 60 babies (26.3%) Vacuum used in 33 babies (15.0%) Cesarean section in 33 babies (9.8%) Forceps in 9 babies (4.2%) and others such as version and destructive measures in 9 babies (4.1%) 7. Intervals between the 1st and 2nd delivery were analyzed and 93% of 2nd twins were delivered within minutes after 1st delivery. 8. The main complications of twin deliveries were totemic (45.5%), second was postmarital hemorrhage (19.6%) and third was hydrations (7.1%) 9. The mean percental mortality of 1st and 2nd twins was 12.52% and 16.96% respectively of which main cause of death were their prematurity.

• 한국전자파학회논문지
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• 제20권7호
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• pp.589-602
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• 2009

DVB-H 수신기가 내장된 GSM 900 방식의 휴대전화 단말은 두 개의 통신 시스템이 공존하고 있어 GSM 신호의 간섭으로 인해 DVB 방송 신호의 수신 성능이 저하되는 현상이 발생한다. 본 논문에서는 GSM과 DVB-H 복합 단말에서 DVB-H 수신기로 간섭을 일으키는 GSM 신호를 제거하기 위해 DSP 기법을 이용한 디지털 필터를 적용하여 DVB-H 수신기의 성능을 높일 수 있는 시스템을 제안한다. DVB-H 수신기의 복조단에서 GSM 변조 선호와 OFDM 선호의 특성이 서로 다른 점을 이용한 잡음 제거 필터링 알고리즘으로 DVB 신호와 함께 유입된 GSM 신호의 간섭 성분을 제거함으로써 DVB 수신 성능을 크게 향상시킬 수 있다.

• 의료법학
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• 제7권2호
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• pp.219-268
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• 2006

In July 1989, Korea had achieved the national medical insurance system comprehensively covering the whole population since its inception of 12 years before, and subsequently the plural medical insurers had integrated to the unique health insurer system in July 2000. But there yet remain some problems to be improved under low contributions rates and poor benefit packages, especially the shortage of assuring beneficiaries' rights. The Health Insurance Appeal System is composed of a two-tiered system of committee. The Formal Objection Committees built in the National Health Insurance Corporation and in the Health Insurance Review Agency respectively examine the formal objections to the decisions of the Corporation, or the Review Agency. And the Dispute Mediation Committee built under the command of the Minister of Health and Welfare reviews the protests against the decisions on the formal objections by each Formal Objection Committee. To cope with the appellant in relation to the administration on the qualification of the insureds, contributions, and insurance benefits etc, is found to be unsatisfactory. There's the reason of poor function on right-relief caused by the loose composition of the Appeal Committee, the deficit of people's recognition and P.R., the lack of professional manpower and the Committee's independency, and time lag in making decisions and so on. Consequently the Appeal System should be improved to secure the rights-relief function, to empower the professionalism of the Appeal Committee, to strengthen P.R. for the beneficiaries, to build up the staff's proficiency through training, and to develop the quality of administrative services.