• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년 영문 학술대회
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• pp.330-339
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• 2008

Ground-based interceptors(GBI) comprise a major element of the strategic defense against hostile targets like Intercontinental Ballistic Missiles(ICBM) and reentry vehicles(RV) dispersed from them. An optimum design of the subsystems is required to increase the performance and reliability of these GBI. Propulsion subsystem design and optimization is the motivation for this effort. This paper describes an effort in which an entire GBI missile system, including a multi-stage solid rocket booster, is considered simultaneously in a Genetic Algorithm(GA) performance optimization process. Single goal, constrained optimization is performed. For specified payload and miss distance, time of flight, the most important component in the optimization process is the booster, for its takeoff weight, time of flight, or a combination of the two. The GBI is assumed to be a multistage missile that uses target location data provided by two ground based RF radar sensors and two low earth orbit(LEO) IR sensors. 3Dimensional model is developed for a multistage target with a boost phase acceleration profile that depends on total mass, propellant mass and the specific impulse in the gravity field. The monostatic radar cross section (RCS) data of a three stage ICBM is used. For preliminary design, GBI is assumed to have a fixed initial position from the target launch point and zero launch delay. GBI carries the Kill Vehicle(KV) to an optimal position in space to allow it to complete the intercept. The objective is to design and optimize the propulsion system for the GBI that will fulfill mission requirements and objectives. The KV weight and volume requirements are specified in the problem definition before the optimization is computed. We have considered only continuous design variables, while considering discrete variables as input. Though the number of stages should also be one of the design variables, however, in this paper it is fixed as three. The elite solution from GA is passed on to(Sequential Quadratic Programming) SQP as near optimal guess. The SQP then performs local convergence to identify the minimum mass of the GBI. The performance of the three staged GBI is validated using a ballistic missile intercept scenario modeled in Matlab/SIMULINK.

• Wind and Structures
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• 제19권4호
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• pp.443-465
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• 2014

Hyperbolic thin-shell cooling towers have complicated vibration modes, and are very sensitive to the effects of group towers and wind-induced vibrations. Traditional aero-elastic models of cooling towers are usually designed based on the method of stiffness simulation by continuous medium thin shell materials. However, the method has some shortages in actual engineering applications, so the so-called "equivalent beam-net design method" of aero-elastic models of cooling towers is proposed in the paper and an aero-elastic model with a proportion of 1: 200 based on the method above with integrated pressure measurements and vibration measurements has been designed and carried out in TJ-3 wind tunnel of Tongji university. According to the wind tunnel test, this paper discusses the impacts of self-excited force effect on the surface wind pressure of a large-scale cooling tower and the results show that the impact of self-excited force on the distribution characteristics of average surface wind pressure is very small, but the impact on the form of distribution and numerical value of fluctuating wind pressure is relatively large. Combing with the Complete Quadratic Combination method (hereafter referred to as CQC method), the paper further studies the numerical sizes and distribution characteristics of background components, resonant components, cross-term components and total fluctuating wind-induced vibration responses of some typical nodes which indicate that the resonance response is dominant in the fluctuating wind-induced vibration response and cross-term components are not negligible for wind-induced vibration responses of super-large cooling towers.

• 한국연극학
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• 제49호
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• pp.171-208
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• 2013

Site-specific performance is always the real on-site work taking place at the site. Hence, it deals with the reality, in other words, the time of creation and formation. And it creates value and meaning through the interaction and continuous direct communication process between the performers, audience and the local residents. In this performance, the audience's status as the passive observer changes. They become the co-agent who actively lead and complete the performance through their own experience. We have examined the The Working Methods of Site-specific Performance and Aesthetics of Effect through four Korean performances ; Marie, An aesthetic experiment of site as the storyteller; Heterotopia and Urban Movement Research or Play: We Will Move Your Sofa, as performances which have Revealed history, politics, institution engraved in the site ; A Song of Mandala and Miracle, as a ritualistic site-specific performance at the historic site. Some remarks on Site-specific performance ; First, In Site-specific performance, the habitus peculiar to the stage art and the mode of reception are changed. Second, a new mode of theatrical communication requires creator and audience to have a sharp aesthetic sensibility and to change one's perceptual habit. Third, Site-specific performance can act as a demonstration for the viewpoints of political activism through what could be called a dramatic close-up effect. Fourth, Site-specific performance also has the risk of merely becoming an unfocused and scattered performance or degenerating into a pseudo-sightseeing. To avoid this, an in-depth study of the site and its socio-cultural context, and the clear motivation with which one is trying to reveal and tell from the site must be indispensable. As the co-agent, the audience should also be aware and think about what the given performance signifies today.

• Journal of Korea Trade
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• 제25권5호
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• pp.58-73
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• 2021

Purpose - In the context of economic globalization and the continuous development of international trade, as countries around the sea peninsula, port construction is particularly important. Based on the research on the influencing factors of port logistics development based on the allocation analysis, QCA (Qualitative Comparative Analysis) provides the basis for the planning and policy of port logistics development and has important theoretical value and practical significance for improving the level of port logistics management, reducing logistics operating costs and increasing economic benefits. In the tide of global integration for the development of port logistics, promote the growth of foreign trade economy of the city. It is also of great significance to the development and progress of commerce and trade. Design/methodology - Based on the relevant data samples of various ports in South Korea, this paper uses fsQCA (fuzzy set Qualitative Comparative Analysis) to integrate and analyze the influence mechanism of port logistics development and extracts five influencing factors of port logistics development, including the port's scale and infrastructure in the hard environment, port-neighboring enterprises in the soft environment, hinterland economy and government support. Findings - The five factors are unable to separately constitute the necessary and sufficient conditions of port logistics development, only a combined model can influence lake port logistics development. The scale and infrastructure of the port itself and port-neighboring ring enterprises are the main core conditions, which work together on the port, affect the throughput capacity of the port, and promote the development of port logistics. When the port-neighboring enterprises are not complete and the scale is low, the growth of port throughput will be restrained and the development of port logistics will be affected, whether the hinterland economic benefits are general, the development of port-neighboring enterprises is insufficient, or the government supports are limited. Originality/value - Through the research on the development of port logistics in South Korea from the perspective of configuration, this paper finds the configuration influence of hard environment and soft environment on the development of port logistics, which has important theoretical and practical significance for better promoting the development of port logistics in South Korea.

• 한국컴퓨터정보학회논문지
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• 제26권1호
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• pp.155-161
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• 2021

최근 UAV를 활용하는 정밀 추적이나 임무완수 등의 군사 목적의 연구가 활발하게 진행되고 있다. 특히 앞서가는 유도 UAV의 자세 정보를 추정하고 이 정보를 이용하여 임무 UAV가 스텔스로 따라가서 자신의 임무를 완수하는 기능이 필요한 경우에는 유도 UAV의 자세 정보 추정 속도를 실시간으로 처리 해야만 한다. 최근까지 영상처리와 칼만 필터를 사용해서 앞서가는 유도 UAV의 자세정보를 정밀하게 추정하는 연구가 수행되어 왔으나 처리과정의 순차처리로 인해 처리속도에 있어 문제점이 있어왔다. 따라서 본 연구에서는 영상 처리에 있어 처리영역을 전체영역이 아닌 물체를 포함하는 ROI 영역으로 한정하고 또한 연속적인 처리 과정을 OpenMP 기반의 멀티스레드로 분배하고 스레드동기를 맞추어서 병렬 형태로 처리함으로써 자세정보 추정 속도를 향상시킬 수 있는 방법을 제안한다. 구현 결과를 통해서 기본의 처리에 비해 45%이상 처리 속도를 향상시킴으로써 실시간처리가 가능하게 되어 임무 UAV의 추적 기능 향상을 통한 임무 완수 가능성을 증가시킬 수 있음을 확인하였다.

• Clinical Pain
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• 제19권1호
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• pp.32-35
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• 2020

Treatment-induced neuropathy in diabetes (TIND) is a reversible neuropathy that occurs in patients with diabetes, usually after a fast improvement in glycemic control. TIND is defined as the sudden onset of neuropathic pain or autonomic dysfunction with a large improvement in glycemic control (glycated hemoglobin [HbA1c] level of ≥ 2% over 3 months). We report the first case of a 24-year-old woman with type 1 diabetes mellitus who developed TIND in Korea. Her HbA1c level had decreased from 16.7% to 7.3% within a 3-month period. She developed acute-onset, severe, and continuous burning pain affecting her back and lower extremities. She was administered tapentadol (50 mg), pregabalin (75 mg), and vitamin B with minerals twice daily for neuropathic pain. She complained of orthostatic hypotension; thus, midodrine (2.5 mg) and anti-embolic stockings were prescribed. She almost completely recovered 6 months after the onset. A physician should be aware of TIND and gradually reduce HbA1c levels to prevent the occurrence of TIDN. They must also try to provide relief from severe pain or autonomic dysfunction and emphasize on an almost complete recovery.

• Journal of information and communication convergence engineering
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• 제20권3호
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• pp.174-180
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• 2022

Emotion recognition is an essential component of complete interaction between human and machine. The issues related to emotion recognition are a result of the different types of emotions expressed in several forms such as visual, sound, and physiological signal. Recent advancements in the field show that combined modalities, such as visual, voice and electroencephalography signals, lead to better result compared to the use of single modalities separately. Previous studies have explored the use of multiple modalities for accurate predictions of emotion; however the number of studies regarding real-time implementation is limited because of the difficulty in simultaneously implementing multiple modalities of emotion recognition. In this study, we proposed an emotion recognition system for real-time emotion recognition implementation. Our model was built with a multithreading block that enables the implementation of each modality using separate threads for continuous synchronization. First, we separately achieved emotion recognition for each modality before enabling the use of the multithreaded system. To verify the correctness of the results, we compared the performance accuracy of unimodal and multimodal emotion recognitions in real-time. The experimental results showed real-time user emotion recognition of the proposed model. In addition, the effectiveness of the multimodalities for emotion recognition was observed. Our multimodal model was able to obtain an accuracy of 80.1% as compared to the unimodality, which obtained accuracies of 70.9, 54.3, and 63.1%.

• Archives of Plastic Surgery
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• 제49권2호
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• pp.207-214
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• 2022

Background Fellowship training is becoming more popular in plastic surgery, with over half of residents pursuing advanced training. Here, we investigate how clinical and research fellowship training impacts career trajectory and scholastic achievement in academic plastic surgery. Methods Plastic surgery faculty members, from programs recognized by the American Council of Academic Plastic Surgeons, were identified using institutional Web sites. Data extracted included faculty demographics, training history, academic positions, and research productivity. Continuous and categorical variables were compared using t-tests and chi-square, respectively. Results In total, 949 faculty members were included, with 657 (69%) having completed fellowship training. Integrated program residents were more likely to complete a fellowship when compared with independent residents (p < 0.0001). Fellowship trained faculty were more likely to have graduated from a higher ranked residency program, in terms of both overall and research reputation (p = 0.005 and p = 0.016, respectively). When controlling for years in practice, there was no difference found in number of publications, Hirsch index (h-index), or National Institutes of Health funding between faculty between the two cohorts (p > 0.05). In a subanalysis comparing hand, craniofacial, microsurgery, and research fellowships, those who completed a research fellowship had higher h-indices and were more likely to reach full professor status (p < 0.001 and p = 0.001, respectively). Fellowship training had no effect on being promoted to Chief/Chair of departments (p = 0.16). Conclusion Fellowship training is common among academic plastic surgeons. In this study, both clinical and research fellowships were associated with various aspects of academic success. However, fellowship training alone did not affect attainment of leadership positions.

• 문화기술의 융합
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• 제9권2호
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• pp.251-259
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• 2023

본 연구는 성인대학생의 사회적지지, 대학교육서비스품질, 학습몰입의 관계에서 학습동기의 매개효과를 검증하여 성인대학생의 학습효과 향상과 학습촉진 강화를 위한 학습체계 구축에 기초자료를 제공하고자 하였다. 이를 위하여 대구광역시와 경상북도에 위치한 2~3년제와 4년제 대학교에 재학 중인 성인대학생 573명을 대상으로 설문조사를 실시하였다. 분석한 연구결과는 다음과 같다. 첫째, 사회적지지와 학습몰입의 관계에서 학습동기는 부분 매개효과가 있는 것으로 나타났다. 둘째, 대학교육서비스품질과 학습몰입의 관계에서 학습동기는 완전 매개효과가 있는 것으로 나타났다. 이상의 연구결과는 성인대학생의 학습몰입을 높이기 위해서는 다양한 지지체계 구축과 교육서비스 향상을 위한 지속적인 개발과 노력이 필요하다는 것을 시사한다.

• Membrane and Water Treatment
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• 제15권2호
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• pp.59-66
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• 2024

This study evaluated the performance of a membrane aerated biofilm reactor (MABR) for nitrogen removal from a high-strength ammonia nitrogen-containing wastewater. The experimental setup consisted of four compartments that are sequentially anaerobic and aerobic to achieve complete nitrogen removal. The last compartment of the reactor setup contained a membrane bioreactor (MBR) to reduce sludge production in the system and to obtain a better-quality effluent. Continuous experiment over a period of 47 days showed that MABR exhibited excellent NH₄⁺-N removal efficiency (99.5%) compared to the control setup without MABR (56.5%). The final effluent NH₄⁺-N concentration obtained in the MABR was 2.99±1.56 mg/L. In contrast to NH₄⁺-N removal, comparable TOC removal values in the MABR and the control reactor (99.2% and 99.3%, respectively) showed that air supply through MABR is much more critical for denitrification than for organic removal. Further study to understand the effect of air supply rate and holding pressure on NH₄⁺-N removal in MABR revealed that an increase in both these parameters positively impacted reactor performance. These parameters are related to oxygen supply to the biofilm formed over the membrane surface, which in turn influenced NH₄⁺-N removal in MABR. Among the two different strategies to control biofilm over the membrane surface, results showed that scouring for a duration of 10 min on a weekly basis, along with mixing air supply, could be an effective method.