• 한국산학기술학회논문지
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• 제15권2호
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• pp.603-608
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• 2014

항공기와 자동차 부품과 관련된 많은 제조업에서, 낮은 비중과 높은 강도에서 뛰어난 알루미늄 합금(Al2024)은 효과적으로 사용되었다. 가공소재의 표면거칠기 품위를 위한 정면밀링 가공기술은 이들 분야에서 적용되어 왔다. 챔퍼된 드로우 어웨이 타입의 인서트를 갖는 정면밀링 가공은 단지 이론적으로 완전한 평면을 생산할 수 있다. 그러나 그것은 절삭온도, 소성변형, 동적효과 등으로 인하여 불가능하다. 본 논문에서 실험적 연구는 검증된 고속가공이 가능한 정면밀링커터 바디를 사용하여 Al2024의 고속가공 후 표면거칠기를 개선하기 위하여 수행되었다.

• Journal of Information Processing Systems
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• 제16권3호
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• pp.733-741
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• 2020

A smart dust monitoring system is useful for obtaining information on rough terrain that is difficult for humans to access. One of ways to deploy sensors to gather information in smart dust environment is to use an aircraft in the Amazon rainforest to scatter an enormous amount of small and cheap sensors (or smart dust devices), or to use an unmanned spacecraft to throw the sensors on the moon's surface. However, scattering an enormous amount of smart dust devices creates the difficulty of managing such devices as they can be scattered into inaccessible areas, and also causes problems such as bottlenecks, device failure, and high/low density of devices. Of the various problems that may occur in the smart dust environment, this paper is focused on solving the bottleneck problem. To address this, we propose and construct a three-layered hierarchical smart dust monitoring system that includes relay dust devices (RDDs). An RDD is a smart dust device with relatively higher computing/communicating power than a normal smart dust device. RDDs play a crucial role in reducing traffic load for the system. To validate the proposed system, we use climate data obtained from authorized portals to compare the system with other systems (i.e., non-hierarchical system and simple hierarchical system). Through this comparison, we determined that the transmission processing time is reduced by 49%-50% compared to other systems, and the maximum number of connectable devices can be increased by 16-32 times without compromising the system's operations.

• 한국운동역학회지
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• 제30권2호
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• pp.165-172
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• 2020

Objective: The purpose of this study was to provide quantitative and objective data of throwing movement in baseball catcher through biomechanical analysis. Method: Eight high school baseball catchers (age: 17.3±0.7 yrs, height: 175.3±4.5 cm, weight: 82.5±9.0 kg, Career: 7.4±2.1 yrs) participated and 3-dimentional motion capture system and electromyography (EMG) were used in this study. Results: The maximum center of mass position displacement was observed in forward direction. The linear velocity magnitude of the upper extremity segments were showed as "wrist>elbow>shoulder" which is indicative of kinematic chain. For kinetic EMG data, we also observed the greater muscle activation in the left brachioradial and erector spine muscles muscle that during throwing movement. Conclusion: We expect that biomechanical data from this study will provide important training implications to baseball coaches and trainers in order to effectively train their baseball catchers.

• 한국항행학회논문지
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• 제17권5호
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• pp.574-580
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• 2013

본 논문에서는 박막코팅기술의 공정은 고경도 박막과 질화층의 접합력을 높이기 위하여 적용하였다. 이 박막코팅기술은 프레스 금형에 사용되는 경도와 인성을 얻을 수 있는 복합 박막을 형성했다. 이러한 박막 코팅 생산 기술은 물리증착방법을 이용하여 진공 챔버의 진공도를 증가하고, 건파워의 투사율을 향상시켰다. 티타늄합금 타겟은 각종 정밀가공 부품에 복합박막코팅기술 개발을 통하여 성능과 표면재질을 개선하였다.

• 철학연구
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• 제116권
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• pp.133-154
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• 2010

신념과 같은 심성을 모두 제거하고자 하는 점에서 반직관적인 제거주의에 대한 반대자들은 이 신조가 자기반박적이라고 말했다. 이런 자기반박성 논증에 대한 반론 가운데 램지(William Remsey)의 반론은 가장 상세하며, 성립한다면 결정적인 반론에 속한다. 그는 자기반박성 주장이 실은 전형적인 제거주의에 대한 비판에 지나지 않아서 진정한 자기반박성 논증이 아니며 그래서 성공하지 못했거나, 진정한 자기반박성 논증이라 하더라도 특별히 제거주의만의 단점이 아니기에 성공을 거두지 못했다고 하면서, 제거주의를 자기반박성의 부담에서 벗어나게 하고자 시도했다. 하지만 램지의 이 시도 역시 성공하지 못했다. 그는 단순한 의미론적 전략을 사용하였을 뿐이다. 그의 자기반박성 개념은 너무 좁다. 그렇지만 램지의 논증과정을 검토하다 보면, 맥키(J. L. Mackie)의 화용적 자기반박성이 중요한 역할을 한다는 점이 드러난다. 어떤 형태의 자기반박성이든 화용적 자기반박성에 기반하고 있다. 여기서는 바로 이점에 착안하여 자기반박성에 관한 단순한 해석을 지지하고, 이에 대한 단순한 반박이 충분한 반박을 이라고 논증할 것이다.

• 한국교육학연구
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• 제22권3호
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• pp.67-87
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• 2016

교육활동의 성격과 교육이론의 실행성을 규명하고자 메타 프락시스의 의미를 검토하였다. 메타 프락시스의 중층구조는 다시 메타 프락시스의 되먹임구조를 드러낸다. 교육논의에서 메타 프락시스의 성격을 배제할 수 없는 것은 이 되먹임구조가 교육현장에서 아이러니를 야기하고, 실행 지침 자체가 실행성과 관련되기 때문이다. 인간 활동의 영역에서 교육은 단순히 포이에시스로 파악되어서 안 되며, 프락시스로 파악되어야 한다. 하지만 교육이 이론화하는 과정에서 메타 프락시스의 속성을 지닌다. 그 결과 교육학의 독자성 확보를 정당화해 준다. 특히 메타 프락시스의 중층구조는 교육활동과 교사의 존재와 역할 등에 시사하는 바가 매우 크다는 점을 확인할 수 있다. 이와 관련하여 교육에서 되먹임구조를 상즉(相卽), 상입(相入), 원증(圓證)과 관련하여 파악하였으며, 교사의 존재의의를 할아버지론(論)에 비추어 파악하였다.

• 웰빙융합연구
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• 제4권1호
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• pp.19-25
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• 2021

Purpose: This study seeks to develop behavior-induced automatic separation X-Bin for disposable cup speculators. Some students throw away the contents. Research design, data and methodology: Therefore, environmental beautification workers spend a lot of time sorting disposable cups at school garbage collection sites. Disposable cups that have been thrown away like this are bad in terms of appearance and smell. In addition, cleaning inside garbage affects recycling rates and is closely related to environmental problems. Results: Clean cleaning reduces the amount of garbage incinerated without being recycled and reduces the cost of recycling. According to Korean Social Trends 2020, COVID-19 began to spread, and recycling of disposable items such as disposable cups increased by about 15 percent from the same period last year. Conclusions: These are classified for recycling, and the amount of garbage thrown on the streets is estimated to be larger. In order to prevent COVID-19s, the use of disposable goods is inevitable, but facilities are needed to dispose of them properly.

• The Journal of Korean Physical Therapy
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• 제35권3호
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• pp.83-88
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• 2023

Purpose: This study was to investigate the effect of forward head posture (FHP) and round shoulder posture (RSP) on changes in muscle activities according to shoulder flexion and abduction tasks. Methods: Twenty-two male subjects with no history of neurological, musculoskeletal surgery or injuries, or pain in the spine region within the previous 3-month periods were recruited for this study. Craniovertebral angle (CVA) and Scapula Index were measured before performing 90° abduction and flexion tasks holding a 3kg dumbbell. Muscle activities were measured during the tasks. All measurements except height of the acromion were carried out in a sitting position at the height of the subject's knee angle of 90 degrees, and two tasks were randomly performed with the arm that the subject mainly use to throw the ball. The abduction and flexion angles were checked by the examiner using a goniometer beside the subject. Results: Correlation coefficient analysis between Scapular Index and upper trapezius muscle activity during shoulder abduction task showed significant positive correlation. No significant correlation was observed between CVA, Scapular Index, and other muscle activities. Conclusion: FHP showed increased muscle activation, making it difficult to change muscle activity under lower loads, and RSP was correlated with UT activation in shoulder abduction. Therefore, in the RSP, the loaded shoulder abduction is considered a potential risk factor for increasing shoulder muscle tension. This paper proposes an approach to treating RSP before FHP.

• Journal of Korean Neurosurgical Society
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• 제65권3호
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• pp.370-379
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• 2022

Abusive head trauma (AHT) is the most severe form of physical abuse in children. Such injury involves traumatic damage to the head and/or spine of infants and young children. The term AHT was introduced to include a wider range of injury mechanisms, such as intentional direct blow, throw, and even penetrating trauma by perpetuator(s). Currently, it is recommended to replace the former term, shaken baby syndrome, which implicates shaking as the only mechanism, with AHT to include diverse clinical and radiological manifestations. The consequences of AHT cause devastating medical, social and financial burdens on families, communities, and victims. The potential harm of AHT to the developing brain and spinal cord of the victims is tremendous. Many studies have reported that the adverse effects of AHT are various and serious, such as blindness, mental retardation, physical limitation of daily activities and even psychological problems. Therefore, appropriate vigilance for the early recognition and diagnosis of AHT is highly recommended to stop and prevent further injuries. The aim of this review is to summarize the relevant evidence concerning the early recognition and diagnosis of AHT. To recognize this severe type of child abuse early, all health care providers maintain a high index of suspicion and vigilance. Such suspicion can be initiated with careful and thorough history taking and physical examinations. Previously developed clinical prediction rules can be helpful for decision-making regarding starting an investigation when considering meaningful findings. Even the combination of biochemical markers may be useful to predict AHT. For a more confirmative evaluation, neuroradiological imaging is required to find AHT-specific findings. Moreover, timely consultation with ophthalmologists is needed to find a very specific finding, retinal hemorrhage.

• 영어영문학
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• 제58권6호
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• pp.1215-1233
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• 2012

This essay is an attempt to critique the notion of hybridity that has so far facilitated a liberal multiculturalist reading of White Teeth. For an alternative framework, it posits the multiethnic subject-making to examine in what ways the novel questions the premises of liberal multiculturalism. In this vein, this study suggests that Smith throws some significant light on the underside of holding multiple racial/ethnic identities while not bypassing its utopian possibilities. In case of the first-generation male characters, their crossracial/homosocial friendship becomes a platform for a mode of egalitarian belonging across the racial divide. It further implies a symbolic union between working-class white and nonwhite immigrant. The younger generation, in contrast, undergoes problems of racial, ethnic, cultural affiliations in far more complicated ways than the older one. Above all, White Teeth demonstrates the subtle workings of liberal multiculturalism, within which the younger characters are constructed to be a multiethnic subject in varied modes. It delineates the formation mainly by exploring the persisting legacies of Britain's imperial history that partake in their subject-making. The novel, in doing so, obliquely suggests that the younger generation is to confront the past that is a seminal part of their present life rather than have the freedom to throw it away to be a carefree member of a multicultural society.