• 한국가시화정보학회지
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• 제10권1호
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• pp.47-54
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• 2012

Single Stage To Orbit (SSTO) missions which require its engines to be operated at varying back pressure conditions, use engines operate at high combustion chamber pressures (more than 100bar) with moderate area ratios (AR 70~80). This ensures that the exhaust jet flows full during most part of the operational regimes by optimal expansion at each altitude. Aero-spike nozzle is a kind of altitude adaptation nozzle where requirement of high combustion chamber pressures can be avoided as the flow is adapted to the outside conditions by the virtue of the nozzle configuration. However, the thrust prediction using the conventional thrust equations remains to be a challenge as the nozzle plume shapes vary with the back pressure conditions. In the present work, the performance evaluation of a new aero-spike nozzle is being carried out. Computational studies are carried out to predict the thrust generated by the aero-spike nozzle in varying back pressure conditions which requires the unsteady pressure boundary conditions in the computational domain. Schlieren pictures are taken to validate the computational results. It is found that the flow in the aero-spike nozzle is mainly affected by the base wall pressure variation. The aerospike nozzle exhibits maximum performance in the properly expanded flow regime due to the open wake formation.

• 한국운동역학회지
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• 제15권1호
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• pp.1-18
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• 2005

The purpose of this study was to evaluate performance characteristics. in the success of team attack during volleyball competition. For this, real game was analyzed using S-VHS video camera for three dimensional cinematography. The contents of this research were receive to set time, set to spike time, setter moving distance, ball position during set and attacker's relative ball position during jump and spike, and open area at spike. Among the various kinematical factors considered in this study, the ball height relative spiker and open area were found to be related to offensive performance. This finding implies that although their direct impact were not significant the other factors could have indirect impact on offensive performance by increasing open area. Thus, receiver, setter, assistant attacker, and main attacker should practice for successful performance in each stage. Lastly, it is necessary to develop kinematic variables to evaluate performance characteristics of players. Further study may consider the best defense position against the attack of the opponent player.

• 한국운동역학회지
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• 제17권1호
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• pp.191-199
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• 2007

This study was conducted to examine the biomechanical characteristics of open spike in the volleyball to improve the technique of the volleyball spike. The subjects were six male college and high school athletes. The motions of volleyball spike were filmed by using two Sony VX 2000 Video Cameras. The mechanical factors were angle and angular velocity of body segments in the upper and the lower limbs. The conclusions were as follows; 1. The angle of the shoulder joint of the skilled showed larger than that of the unskilled in impacting of the volley ball spike. 2. The angle of the elbow joint of the skilled showed larger than that of the unskilled in impacting of the volley ball spike. 3. The angle of the wrist joint of the skilled showed smaller than that of the unskilled in impacting of the volley ball spike. 4. The angle of the hip joint of skilled showed larger than that of unskilled in impacting of the volley ball spike. 5. The angle of the knee joint of the skilled and the unskilled showed same in take off and impacting of the volley ball spike, and that of the skilled showed smaller than that of the unskilled in take-off touchdown and touchdown after impact of the volley ball spike. 6. The angle of the ankle joint of skilled showed larger than unskilled in take-off of the volley ball spike. 7. The angular velocity of the shoulder joint, elbow joint, wrist joint of the skilled showed faster than that of the unskilled in impacting of the volley ball spike. Taken together the result of them, I have come to conclusion that knee joint angle in touchdown of the take off should be decreased and knee joint angle in take off should be increased, and then stability of the take off should be made and, and that extension of the elbow joint should be made and wrist joint angle decreased and shoulder and hip joint angle increased, and then C.O.G of the arm and hand should be positioned ahead C.O.G of the body in impacting for effective impact of the spike, and that the transfer of the angular velocity of body segments for effective impact of the spike make from the proximal segment to the distal segment at spike in volleyball.

• 대한수의학회지
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• 제36권3호
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• pp.627-633
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• 1996

To analyze the genomic diversity of transmissible gastroenteritis virus (TGEV), the N-terminal half of the spike (S) glycoprotein gene and nonstructural protein gene (open reading frames 3 and 3-1) were amplified by reverse transcriptase reaction and polymerase chain reaction (RT-PCR), and analyzed using restriction fragment length polymorphism (RFLP) patterns of the amplified DNA. In this study, TGEV Miller (M6) and Purdue (P115) strains were used as reference strains, and two vaccine strains (MSV and STC3) and four Korea isolates (P44, VRI-WP, VRI-41, and VRI-48) were analyzed. All TGEV strains were amplified with three TGEV primer pairs. Although there was some exception in RFLP analysis, this method differentiated TGEV strains into following groups : Miller group (M6 and MSV), Purdue group (PUS, STC3, P44, VRI-WP, VRI-41, and VRI-48). Using Sau3AI and SspI, VRI-48 was differentiated from the Miller and Purdue type viruses. The RT/PCR in conjuction with RFLP analysis was a rapid and valuable tool for differentiating several strains of TGEV. This study revealed the occurences of distinct difference in genome of TGEV strains.

• 한국운동역학회지
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• 제23권1호
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• pp.45-51
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• 2013

The current study developed the analysis program by employing the Polygon Clipping Algorithm to calculate the open area on the court when players try to spike a ball. The program consists of two kinds of output screen. First, on the main output screen, it is possible to calculate both blocked area by net and blockers, and opened area to avoid the blocked area when players spike the ball. Additionally, the secondary output screen shows the moving path of setter and the location of set. Main output screen indicates hitting points of spiking, blocking, and open area. Also, it is possible to analyze the movement of setter, location of set, and hitting point of attacker. The program was tested by comparing real coordinate value and location coordinate value which is operated on the program. To apply this program in the field, future study needs to develop the program that can calculate three dimensions coordinate fast by tracking the location of players or ball in real time.

• 한국운동역학회지
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• 제13권3호
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• pp.253-264
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• 2003

This study aims at finding the structure of spike technique by analysing comparatively the spike action by excellent and by non-excellent players throughout the section from a flying jump to the time of landing for the correct analysis of spike action and tries to help athletes and coaches to execute a scientific training. For the objected person of this study, six of H College athletes three of excellent athletes and three of non-excellent athletes, presently registered as athlete with the Korea Volleyball federation) were chosen, and the factors of analysis were analysed upon performance time of action by section, human body centered displacement, change of articulation angle, speed change of articulation of the upper limbs, uniformity of the articulation of the upper limbs upon impact, etc. The conclusion of this study is as follow: 1. In the time required for taking action, it shows to take $1.067{\pm}0.057$ seconds for the group of excellent athletes and $1.034{\pm}0.033$ seconds for the group of non-excellent athletes. Although there was not big difference between two groups in the performance time of action, it showed that the group of excellent athletes takes longer compared to the group of non-excellent athletes. And it was found by the result of this study that the group of excellent athletes stays longer in the duration of flight. 2. In the displacements of horizontal movement and vertical movement, it was found that the group of excellent athletes have moved more than the group of non-excellent athletes in the horizontal movement of the center of human body 3. In the angles of wrist and knee, it was found that the excellent athletes have shown little than the non-excellent athletes in the entire sections, but that in the angle of elbow, the non-excellent athletes have shown bigger than the excellent athletes.. 4. In the speed of the articulation of the upper limbs upon impact, it was found that the group of excellent athletes have shown bigger than the group of non-excellent athletes, and that in the maximum value of the articulation of the upper limbs, the maximum value for the hand was indicated upon impact and that forearm and upper arm have shown the maximum value just before the impact. 5. In the uniformity of articulation of the upper limbs at the time of impact, the group of excellent athletes showed bigger than the group of non-excellent athletes in all the articulations.

• 영미문화
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• 제14권1호
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• pp.241-267
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• 2014

Media representations of race have attempted to contain blackness by packaging and commodifying it to reflect and affect preconceptions and prejudices of dominant culture. From the early beginnings of blackface minstrelsy as entertainment form in the $19^{th}$ century, representations of African Americans in popular culture and mainstream media have been closely associated with the notion of performance. The performative nature of racial representations is situated within the discursive struggle over what it meant to be Black, or what it meant to be labeled and portrayed as Black in American culture. This essay discusses four films that contain performances of "blackness" that assemble race and gender in complex configurations: Bamboozled (Spike Lee, 2000), Girl 6 (Spike Lee, 1996), Big Momma's House (Raja Gosnell, 2000), and White Chicks (Keenen Ivory Wayans, 2004). I explore how the performative nature of "blackness" is emphasized, thematized, and problematized in these films through the physicality of corporeal figures that embody the close link between race and gender identities. Once we are cognizant of the fact that race and gender are fabricated cultural constructs and performative acts, we can recognize that notions of "blackness" and "femininity" are not naturalized or essentialist, but open to recontextualization and revision.

• IMMUNE NETWORK
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• 제20권5호
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• pp.41.1-41.11
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• 2020

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) is a positive-sense single-stranded RNA (+ssRNA) that causes coronavirus disease 2019 (COVID-19). The viral genome encodes twelve genes for viral replication and infection. The third open reading frame is the spike (S) gene that encodes for the spike glycoprotein interacting with specific cell surface receptor - angiotensin converting enzyme 2 (ACE2) - on the host cell membrane. Most recent studies identified a single point mutation in S gene. A single point mutation in S gene leading to an amino acid substitution at codon 614 from an aspartic acid 614 into glycine (D614G) resulted in greater infectivity compared to the wild type SARS-CoV2. We were interested in investigating the mutation region of S gene of SARS-CoV2 from Korean COVID-19 patients. New mutation sites were found in the critical receptor binding domain (RBD) of S gene, which is adjacent to the aforementioned D614G mutation residue. This specific sequence data demonstrated the active progression of SARS-CoV2 by mutations in the RBD of S gene. The sequence information of new mutations is critical to the development of recombinant SARS-CoV2 spike antigens, which may be required to improve and advance the strategy against a wide range of possible SARS-CoV2 mutations.

• 한국작물학회지
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• 제55권1호
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• pp.83-90
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• 2010

수년 동안 국내 전역에서 수집된 수수 179 유전자원을 공시하여 작물학적 특성조사를 통한 품종육성의 기초자료를 제공코자 수행하였던 바 그 결과를 요약하면 다음과 같다. 1. 수수의 수형은 산수형, 소경수수형, 반소경수수형, 극밀수형, 및 밀수형의 5가지 수형이 존재하였으며, 수형별 빈도를 보면 소경수수형이 38.0%(68자원)로 가장 많았으며, 극밀수형 및 밀수형이 각각 16.2%, 7.8%로 가장 적었다. 2. 수수 이삭의 까락 유무는 28.5%(51자원)가 까락을 갖고 있었으며, 나머지 71.5%(128자원)는 까락이 없는 것으로 분류되었다. 3. 종실형태는 43.0%(77자원)가 원형으로 가장 많이 차지하였으며, 편원형이 7.3%(13자원)로 가장 적었다. 종피색은 황갈색이 84.4%(151자원)로 가장 많았으며, 갈색 및 흰색이 똑같이 1.1%로 가장 적었다. 4. 수수 179자원의 출수소요일은 67~88일의 범위를 나타내어 변이폭이 컷으며, 평균은 77.4일이었다. 출수소요일의 분포는 179자원 중 76~80일이 37.4%(67자원)로 가장 많았으며, 86일 이상도 5.6%이었으며, 70일 이전에 출수한 자원도 10.0%를 나타내었다. 5. 간장은 92~360 cm의 범위를 보였으며, 평균은 253.8 cm로 변이의 폭이 컷다. 간장의 분포는 291~310 cm가 20.6% (37자원)로 가장 많았다. 6. 수장은 15~49 cm의 범위를 보였고, 평균 28.8 cm이었다. 수장의 분포는 31~35 cm가 26.3%(47자원)로 가장 많았으며, 15 cm 이하가 0.6%로 가장 적었다. 7. 생육일수는 110~146일의 범위를 나타내어 변이 폭이 상당히 큼을 알 수 있었고, 평균은 125.5일이었다. 생육기간의 빈도는 111~115일이 39.7%(71자원)로 가장 많았으며, 110일 이하와 141일 이상에 속하는 자원도 각각 2, 23자원이나 되었다. 8. 1수립수의 범위는 163~4,532개로 변이 폭이 상당히 컷으며, 평균은 2,068.6개 이었다. 1수립수 분포는 1,601~2,000개가 25.7%(46자원)로 가장 많았다. 9. 공시된 179 유전자원의 1000립중은 범위가 10.6~38.1 g으로 변이폭이 컷으며, 평균은 25.6 g이었다. 1000립중의 분포는 26.0~30.0 g가 전체의 44.1%(79자원)로 가장 많았다

• 한국인터넷방송통신학회논문지
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• 제21권3호
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• pp.107-114
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• 2021

최근 다양한 분야에 인공지능 기술이 도입되고, 학계 관심이 늘어남에 따라 다양한 기계학습 모델들이 여러 프레임워크에서 운용되고 있다. 하지만 이러한 프레임워크들은 서로 다른 데이터 포맷을 가지고 있어, 상호운용성이 부족하며 이를 극복하기 위해 오픈 신경망 교환 포맷인 ONNX가 제안되었다. 본 논문에서는 여러 기계학습 모델을 ONNX로 변환하는 방법을 설명하고, 통합된 ONNX 포맷에서 기계학습 기법을 판별할 수 있는 알고리즘 및 추론 시스템을 제안한다. 또한, ONNX 변환 전·후 모델의 추론 성능을 비교하여 ONNX 변환 간 학습 결과의 손실이나 성능 저하가 없음을 보인다.