• 한국항행학회논문지
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• 제27권5호
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• pp.552-560
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• 2023

항공기 공중 충돌사고는 대규모 인명 피해를 초래할 수 있는 위험한 사건이다. 이를 예방하기 위해 민간 항공에서는 TCAS(traffic alert and collision avoidance system) 장착을 의무화하였으며, 새로운 기술의 도움을 받아 더욱 정밀하게 발전하고 있다. 한국에서 개인적으로 TCAS 연구를 위한 데이터를 수집하는데는 절차적인 어려움이 있다. 이를 해결하기 위해 ADS-B(automatic dependent surveillance-broadcast)와 Mode-S(mode-select)를 활용하면 TCAS RA(resolution advisory)의 정보 획득이 가능하다. ADS-B Exchange와 Opensky-Network에서 보관중인 데이터베이스를 제공받아 연구에 활용하였으며, 3건의 TCAS RA 발생 사례를 시각화하였다. 또한 2023년 전반기 국내 TCAS RA 발생사례를 분류한 후 그 특징을 분석하였다. 이를 통해 ADS-B와 Mode-S 데이터의 유효성을 확인하고, 발전방향을 모색하였다.

• 철학연구
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• 제142권
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• pp.265-294
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• 2017

인류역사의 초기에 한 사회의 통치그룹은 그들의 통치를 정당화할 명분 즉 통치이념을 필요로 했다. 중국의 경우 상고시대 통치이념의 중추는 원래 '제(帝)' 또는 '상제(上帝)'였는데, 이후 '천(天)'으로 대체되었다. 그래서 이 천이 통치명분을 준다는 주장이 있었다. 이것이 왕권을 '천이 준다'는 '천명(天命)'사상이며, 이 천명사상이 상대적으로 세련된 형태로 통치이념화한 것은 주(周)가 중앙정권을 차지하면서이다. 이 주(周)의 체제질서를 조직화한 것이 이른바 '주례(周禮)'이다. 이후 이 체제가 붕괴되었는데, 주례를 바람직한 사회질서로 인정하는 이들은 이 주례 붕괴 현상이 사회적으로 나타난 상황을 '난세(亂世)'로 본다. 이 상황을 종결 짓고, 당시의 중국천하를 통일한 나라가 진(秦)이다. 통일 후의 진왕조(秦王朝)가 급격하게 망한 후 그 뒤를 이어받은 왕조인 한조(漢朝)의 지배세력 역시 그들의 정권획득을 정당화할 통치이념을 수립할 필요가 있었다. 한조(漢朝)의 통치이념 확립에 기여한 대표자는 동중서(董仲舒)인데, 그의 기본적 사상은 공자(孔子)의 "춘추(春秋)"에 기반을 두는 유교사상이다. 그는 "춘추"의 한 해석인 "춘추공양전(春秋公羊傳)"에 따라 한조의 통치이념 마련에 기여하였다. 이 해석 관점은 종교적 천관념에 기반한다. 동중서(董仲舒)는 하늘과 사람 사이는 원래 교감, 소통할 수 있도록 되어 있다고 한다. 동중서(董仲舒)의 사상은 기본적으로는 통치자의 통치권의 근거를 하늘에 두려는 정치신학의 의미를 가진다. 또, 한편으로는 자연재이의 일차적 책임을 최고통치자에 둠으로써 최고통치자의 권력을 견제하려는 이론적 수단을 가지려는 의미도 있다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제22권4호
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• pp.303-329
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• 2019

Intestinal failure (IF) is the critical reduction of the gut mass or its function below the minimum needed to absorb nutrients and fluids required for adequate growth in children. Severe IF requires parenteral nutrition (PN). Pediatric IF is most commonly due to congenital or neonatal intestinal diseases or malformations divided into 3 groups: 1) reduced intestinal length and consequently reduced absorptive surface, such as in short bowel syndrome (SBS) or extensive aganglionosis; 2) abnormal development of the intestinal mucosa such as congenital diseases of enterocyte development; 3) extensive motility dysfunction such as chronic intestinal pseudo-obstruction syndromes. The leading cause of IF in childhood is the SBS. In clinical practice the degree of IF may be indirectly measured by the level of PN required for normal or catch up growth. Other indicators such as serum citrulline have not proven to be highly reliable prognostic factors in children. The last decades have allowed the development of highly sophisticated nutrient solutions consisting of optimal combinations of macronutrients and micronutrients as well as guidelines, promoting PN as a safe and efficient feeding technique. However, IF that requires long-term PN may be associated with various complications including infections, growth failure, metabolic disorders, and bone disease. IF Associated Liver Disease may be a limiting factor. However, changes in the global management of IF pediatric patients, especially since the setup of intestinal rehabilitation centres did change the prognosis thus limiting "nutritional failure" which is considered as a major indication for intestinal transplantation (ITx) or combined liver-ITx.

• 패션비즈니스
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• 제13권6호
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• pp.125-136
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• 2009

The main objective of this research was to understand the characteristics of complementary color scheme through the analysis of contemporary women's fashion color coordination as they appear in the 'Collections'. Data collection of 115 was done through review of 'pr$\hat{e}$t-$\grave{a}$-porter Collections' of four cities; Milan, London, New York, Paris. Statistical analysis of frequency and also qualitative interpretation of characteristics of complementary color harmony characteristics which appeared in four collections were completed. The main findings were as followed; (1) Only 115 complementary color schemes out of 4968 two color combinations appeared. Compared the comparative ratios of appearance frequency between the two color combination and the complementary color harmony, London showed the highest, and followed by New York, and Milan and Paris. (2)The combined color type of 'red+green' was the most frequently appeared, and followed by 'violet+yellow' and 'orange+blue'. For the type of tone harmony, the contrast tone showed the most, and followed by the similarity and identity. According to the type of complementary color combination, the type of tone harmony used differently. Some differences showed in the types of color harmony and tone harmony between collections. (3) The complementary color scheme which shown in four collections harmonized two opposite colors mainly through the strong tone contrast and this could cause tension along with interest in the image. The complementary colors intensified and brought out the attributes each other. More details, high contrast of two complementary colors of yellow and violet created a vibrant look especially when used at higher saturation. Sometimes, however, some tone variations of two hues neutralized the strong effect and sometimes enhanced each other. When they used in similarity tones or identity tones in light colors, the tension was reduced and became softened but still presented nice harmony. In the type of 'red+green' color harmony, the various color combinations were demonstrated, mostly through tone manipulation of green color. The similarity tone harmony, which used the most, could effect a better sense of harmony and present more sophisticated looks. When used in contrast tone harmony, some changes in its own color which have only one color of two the excessive intensity led a good harmony. The 'orange+blue' color harmony was shown the least and used three tone harmony almost the same ratio. In this color harmony, blue amplified its energy and brilliance of orange and seemed to work better when one color was at a lower intensity than the other. In harmony with a similarity and an identity tone, this color harmony produces a stable and calm image. (4) The complementary scheme appeared more frequently in the S/S collections than in A/W collections and showed some differences in the types of color harmony and tone harmony between seasons, however, no big differences between collections.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1022-1027
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• 2003

The Motion controllers provide the sophisticated performance and enhanced capabilities we can see in the movements of robotic systems. Several types of motion controllers are available, some based on the kind of overall control system in use. PLC (Programmable Logic Controller)-based motion controllers still predominate. The many peoples use MCU (Micro Controller Unit)-based board level motion controllers and will continue to in the near-term future. These motion controllers control a variety motor system like robotic systems. Generally, They consist of large and complex circuits. PLC-based motion controller consists of high performance PLC, development tool, and application specific software. It can be cause to generate several problems that are large size and space, much cabling, and additional high coasts. MCU-based motion controller consists of memories like ROM and RAM, I/O interface ports, and decoder in order to operate MCU. Additionally, it needs DPRAM to communicate with host PC, counter to get position information of motor by using encoder signal, additional circuits to control servo, and application specific software to generate a various velocity profiles. It can be causes to generate several problems that are overall system complexity, large size and space, much cabling, large power consumption and additional high costs. Also, it needs much times to calculate velocity profile because of generating by software method and don't generate various velocity profiles like arbitrary velocity profile. Therefore, It is hard to generate expected various velocity profiles. And further, to embed real-time OS (Operating System) is considered for more reliable motion control. In this paper, the structure of chip-based precision motion controller is proposed to solve above-mentioned problems of control systems. This proposed motion controller is designed with a FPGA (Field Programmable Gate Arrays) by using the VHDL (Very high speed integrated circuit Hardware Description Language) and Handel-C that is program language for deign hardware. This motion controller consists of Velocity Profile Generator (VPG) part to generate expected various velocity profiles, PCI Interface part to communicate with host PC, Feedback Counter part to get position information by using encoder signal, Clock Generator to generate expected various clock signal, Controller part to control position of motor with generated velocity profile and position information, and Data Converter part to convert and transmit compatible data to D/A converter.

• 한국건축시공학회지
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• 제19권6호
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• pp.529-538
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• 2019

태풍은 전 세계적으로 상당한 재정적 피해를 입힌다. 정부, 지방자치단체, 보험회사는 태풍 위험 평가 모델을 개발하여 자연 재해에 따른 재정 위험을 정량화하고 완화하고자 한다. 이에 태풍 위험 평가 모델의 중요성이 증가하고 있으며, 정교한 평가를 위한 국지적 취약성을 반영하는 것이 중요하다. 자연 재해와 관련된 경제적 손실에 대한 실질적인 기존 연구들이 필수적인 위험 지표를 확인했지만 취약성과 경제적 손실 사이의 상관관계를 다루는 종합적인 연구가 여전히 필요하다. 본 연구의 목적은 태풍 매미로 인한 손실 데이터를 바탕으로 태풍 피해 예측 함수에 대한 평가지표를 개발하기 위함이다. 본 연구에서는 취약성 함수를 만들기 위해 풍속과 해안가로부터의 거리, 그리고 건물가치, 건물 유형, 층수 및 지하층 수의 정보를 사용하였으며 국내 보험사가 제공하는 태풍 매미의 실제 손실 기록을 분석하고 취약성 함수를 개발하여 최대 손실 발생의 예방에 기여하고자 하였다. 본 연구의 결과와 지표는 건물의 실제 재정 손실과 지역 취약성을 반영하는 정부 기관 및 보험 회사의 취약성 함수 개발을 위한 실질적인 지침으로 활용될 수 있다.

• 한국의상디자인학회지
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• 제10권3호
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• pp.1-13
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• 2008

The purpose of this research is to study the cause of obstruction in various knit pattern structures by understanding the needs of the customers, and to develop knitted fabric goods that satisfy the individual taste of consumers and that reflecting the latest fashions. Actual conditions of the manufacturer's designing processes must be examined. In addition, a comparison analysis of fashion sensibilities and preferences between producers and consumers had been made in order to study developing knit pattern structures. Questionnaires and interviews had been used as research methods. The research involved two groups: one group consisted of 57 producers, which included designers, programmers, and merchandisers working for a knit manufacturer in Seoul, while the other group consisted of 74 consumers, which included students with knitted fabric design as their major and those who have working knowledge of knitted fabrics. For a more accurate evaluation, 28 out of 150 patterns have been selected through a preliminary study conducted by 24 designers. On the 28 knit patterns, a sensibility evaluation had been made through the use of the sense of sight and sense of touch, which was followed by a frequency analysis, cluster analysis, and t-test using SPSS 12.0. The results are as follows: the fashion sensibility evaluation on knit patterns showed that structures, such as racking II or lace II, are typically elegant ('elegance'), while structures, such as links I or racking I, are typically 'active.' Furthermore, a 'country' image was displayed in structures such as cable I, cable II, and miss II. Links I appeared as 'sophisticated'. Miss I and milano were said to have 'modem' images. Lace II was regarded as 'ethnic', while racking II was said to have a 'romantic' image. 2:1 rib and milano were generally thought to be manly ('manish'). The fashion sensibility scale for each knit pattern has been made based on the above results. Based on producer and consumer responses, the sensibility evaluation on knit pattern structures showed that the two groups had similar preferences in knit pattern structures. Therefore, the fashion sensibility scale developed in this study can be used as a basic data for structure development when designing knitted fabric goods.

• International Journal of Aeronautical and Space Sciences
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• 제8권1호
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• pp.10-20
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• 2007

For spacecraft attitude control, reaction wheel (RW) steering laws with more than three wheels for three-axis attitude control can be derived by using a control allocation (CA) approach.1-2 The CA technique deals with a problem of distributing a given control demand to available sets of actuators.3-4 There are many references for CA with applications to aerospace systems. For spacecraft, the control torque command for three body-fixed reference frames can be constructed by a combination of multiple wheels, usually four-wheel pyramid sets. Multi-wheel configurations can be exploited to satisfy a body-axis control torque requirement while satisfying objectives such as minimum control energy.1-2 In general, the reaction wheel steering laws determine required torque command for each wheel in the form of matrix pseudo-inverse. In general, the attitude control command is generated in the form of a feedback control. The spacecraft body angular rate measured by gyros is used to estimate angular displacement also.⁵ Combination of the body angular rate and attitude parameters such as quaternion and MRPs(Modified Rodrigues Parameters) is typically used in synthesizing the control command which should be produced by RWs.¹ The attitude sensor signals are usually corrupted by noise; gyros tend to contain errors such as drift and random noise. The attitude determination system can estimate such errors, and provide best true signals for feedback control.⁶ Even if the attitude determination system, for instance, sophisticated algorithm such as the EKF(Extended Kalman Filter) algorithm⁶, can eliminate the errors efficiently, it is quite probable that the control command still contains noise sources. The noise and/or other high frequency components in the control command would cause the wheel speed to change in an undesirable manner. The closed-loop system, governed by the feedback control law, is also directly affected by the noise due to imperfect sensor characteristics. The noise components in the sensor signal should be mitigated so that the control command is isolated from the noise effect. This can be done by adding a filter to the sensor output or preventing rapid change in the control command. Dynamic control allocation(DCA), recently studied by Härkegård, is to distribute the control command in the sense of dynamics⁴: the allocation is made over a certain time interval, not a fixed time instant. The dynamic behavior of the control command is taken into account in the course of distributing the control command. Not only the control command requirement, but also variation of the control command over a sampling interval is included in the performance criterion to be optimized. The result is a control command in the form of a finite difference equation over the given time interval.⁴ It results in a filter dynamics by taking the previous control command into account for the synthesis of current control command. Stability of the proposed dynamic control allocation (CA) approach was proved to ensure the control command is bounded at the steady-state. In this study, we extended the results presented in Ref. 4 by adding a two-step dynamic CA term in deriving the control allocation law. Also, the strict equality constraint, between the virtual and actual control inputs, is relaxed in order to construct control command with a smooth profile. The proposed DCA technique is applied to a spacecraft attitude control problem. The sensor noise and/or irregular signals, which are existent in most of spacecraft attitude sensors, can be handled effectively by the proposed approach.

• 중소기업융합학회논문지
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• 제3권2호
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• pp.51-56
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• 2013

센서 네트워크에서는 데이터의 실시간 처리가 중요한 요소 중의 하나이다. 각 노드들이 감지한 데이터들은 정해진 시간 내에 전송 되어야만 필요한 시기에 정확한 처리가 가능하다. 따라서 노드들이 데이터를 정해진 시간 내에 제대로 전달하고 있는가를 점검하는 것은 매우 중요하다. 최근 리얼타임 임베디드 시스템이 점점 더 정확해져서 신뢰성 있고 정교한 서비스를 제공할 수 있게 되었다. 임베디드 시스템의 본래의 복잡함 때문에 물리세계에서의 예측의 어려움과 안전한 설계의 어려움은 런타임에서 시스템 제약사항에 위배되는 것과 예상치 못한 상황을 야기시키는 원인이 된다. 각 노드들이 감지한 데이터를 정해진 시간 내에 전달해야 필요한 시기에 적합한 처리가 가능하기 때문에 본 논문에서는 데이터 전송시간에 대한 모니터링을 통하여 센서 네트워크에 존재하는 노드들이 허용시간 범위 내에서 서버로 데이터를 전송하고 있는가를 확인하기 위한 데이터 전송시간 분석 시스템을 구현 하였다. 시스템 구현을 위하여 데이터 전송시간 분석을 위한 절차를 제시했고, 제시한 절차에 따라 전송시간을 분석하기 위해 필요한 시간차 분석 방법, 데이터 송수신 시간 수집 방법 및 데이터 전송시간 계산 방법을 제시했다.

• 한국산학기술학회논문지
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• 제18권4호
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• pp.718-725
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• 2017

액체저장탱크는 화학물질을 다루는 산업단지의 주요한 구조물로서, 지진으로 인한 구조물의 손상은 화학물질의 유출, 화재, 폭발 등의 추가적인 피해를 야기한다. 따라서 액체저장탱크의 지진 취약성을 사전에 효율적으로 평가하고, 지진에 대비하는 일이 필수적이라고 할 수 있다. 지진으로 인해 진동하는 액체저장탱크는 액체-구조물의 상호작용으로 탱크 벽체에 유동압력이 작용하며, 이는 탱크의 응력을 증가시키고 구조적 손상을 일으키는 원인이 될 수 있다. 한편, 구조물의 지진 취약성은 여러 불확실성 요인들을 고려하여 정해진 한계상태에 대한 파괴확률을 산정함으로써 평가하게 되는데, 보다 정확한 액체저장탱크 지진 취약도 평가를 위해서는 신뢰성 해석 과정에서 정교한 유한요소 해석이 요구된다. 따라서 본 연구에서는 최근에 신뢰성 해석 소프트웨어와 유한요소 해석 소프트웨어를 서로 연동시켜 개발된 FERUM-ABAQUS를 활용한 유한요소 신뢰성 해석을 통해 액체저장탱크의 파괴확률을 계산하였다. 이러한 유한요소 신뢰성 해석 기법은 두 소프트웨어 간의 자동적인 데이터 교환이 가능하여 보다 효율적으로 구조물의 지진 취약성을 평가할 수 있으며, 이를 통해 얻은 파괴확률 결과를 바탕으로 지진 강도에 따른 액체저장탱크의 지진 취약도 곡선을 성공적으로 도출하였다.