• Smart Structures and Systems
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• 제29권6호
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• pp.767-775
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• 2022

Metal additive manufacturing (AM), also known as metal three-dimensional (3D) printing, produces 3D metal products by repeatedly adding and solidifying metal materials layer by layer. During the metal AM process, products experience repeated local melting and cooling using a laser or electron beam, resulting in product defects, such as warpage, cracks, and internal pores. Such defects adversely affect the final product. This paper proposes the in situ monitoring-based warpage prediction of metal AM products with experimental feature extraction. The temperature profile of the metal AM substrate during the process was experimentally collected. Time-domain features were extracted from the temperature profile, and their relationships to the warpage mechanism were investigated. The standard deviation showed a significant linear correlation with warpage. The findings from this study are expected to contribute to optimizing process parameters for metal AM warpage reduction.

• Journal of Acupuncture Research
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• 제38권3호
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• pp.183-191
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• 2021

Sa-am acupuncture originated in the Chosun Dynasty and is a distinct feature of Korean medicine. It has been used to treat various diseases and conditions in clinical practice however, there is insufficient scientific evidence to support the use of Sa-am acupuncture. We aimed to comprehensively review the clinical studies of Sa-am acupuncture retrieved from national and international databases (MEDLINE, EMBASE, the China National Knowledge Infrastructure, and 3 Korean databases). There were 52 articles reviewed including 29 case studies, 19 randomized controlled trials (RCTs), and 4 uncontrolled trials. Neurological disorders were the most frequently studied, and kidney tonification, and directional supplementation and draining were the most frequently used methods. Overall, the outcomes were generally positive however, there were many additional treatments together with Sa-am acupuncture reported in the case reports, and the quality of evidence was low in the RCTs. Future studies should report the detailed method of practicing Sa-am acupuncture treatment and focus on the specific effect of Sa-am acupuncture with rigorous design to scientifically support the clinical use of Sa-am acupuncture.

• 대한토목학회논문집
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• 제42권2호
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• pp.257-261
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• 2022

건축물의 디자인 자유도 향상, 작업자 안전 향상, 비교적 쉬운 납기예측 등의 이점으로 건설 산업에 적용된 3D 프린팅 기술(Additive manufacturing, AM)은 각종 효과성의 검증과 산업적용이 진행되고 있다. 다만, 기존기술대비 낮은 성숙도로 인해, 건축AM기술의 전주기에 발생하는 새로운 문제들을 해소하기 위한 연구들이 진행 중이다. 본 논문에서는 이러한 문제점 중에서도 현장 환경에 건축물을 적층 시공하는 과정에서, 낮은 시공표면평탄이 적층 제조 형상물에 미치는 영향을 확인한다. 특히 레이저 스캐닝을 통한 3차원 재구성 및 정량 분석을 통해, 낮은 평탄도로 인한 불균일한 적층형상물을 분석하고, 이를 해소하기 위한 적층시공전략을 제안한다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.239-244
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• 2007

Highly efficient and stable white PIN OLED structures have been developed with a focus on possible AM display applications. Due to the use of the novel air-stable Novaled n-dopant material NDN26, the mass production compatibility of the PIN approach is improved. With both a conventional n-dopant, NDN1, and a novel air-stable n-dopant, NDN26, similar performance in efficiency and lifetime are reached. Based on highly a stable red fluorescent emitter system, the Novaled PIN approach allows for reaching ultra-long lifetimes of 1,000,000 hours at a brightness of $1,000\;cd/m^2$, both for top and for bottom emission layouts. Furthermore, inverted PIN structures for a possible use in a-Si backplane applications for AM displays are shown. With a phosphorescent green emitter system it could be demonstrated that for bottom and inverted as well as non-inverted top emission, a brightness of $1,000\;cd/m^2$ can be reached at below 3 V. In addition to low operating voltages and long lifetimes, PIN OLEDs also enable for device structures with extremely low operating voltage drifts, a feature of increasing importance for future AM display developments.

• 동굴
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• 제41권42호
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• pp.15-26
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• 1995

화암동굴은 1980년 2월 16일에 강원도 지방 기념물 33호로 지정, 보호 관리되고 있는 석회동굴이다. 이 동굴의 기본적 학술조사는 1966년 초에 한일 합동 동굴조사대어서 이루어졌으며, 그후 한국동굴보존협회와 한국동굴학회에서 수차례에 걸친 조사가 이루어졌다.(중략)

• 한국통신학회논문지
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• 제30권1C호
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• pp.73-81
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• 2005

본 논문에서는 미리 정의된 키 피쳐(key feature)를 수신된 변조 신호로부터 추출하여 동등 이득 조합(equal gain combining) 기법을 적용하는 자동 변조 인식 알고리즘을 제안하곡 의사 결정 이론(decision-theoretic) 알고리즘과 제안된 알고리즘의 성능을 비교, 분석하였다. 제안된 변조 인식 알고리즘은 키 피쳐 추출 단위인 세그먼트별로 미리 정의된 5 가지 종류의 키 피쳐를 추출하고, 전체 프레임에 걸쳐 평균화된 각 키 피쳐값을 결정-순서도(decision flowchart)에 적용하여 수신 신호의 변조 형식을 구분한다. 제안된 알고리즘의 성능을 검증하기 위하여 아날로그 변조 신호인 AM, FM, SSB 신호와 디지털 변조 신호인 FSK2, FSK4, PSK2, PSK4 신호를 대상으로 SNR의 변화 및 신호 수집 시간의 변화에 따른 변조 인식 성공률을 측정하였다. 그 결과 제안된 알고리즘이 기존의 의사 결정 이론 알고리즘에 거의 근접하는 성능을 나타내면서 낮은 복잡도를 나타내었다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2001년도 춘계학술대회 논문집(한국공작기계학회)
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• pp.239-243
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• 2001

Neural networks are used in the framework of sensorbased tracking control of robot manipulators. They learn by practice movements the relationship between PSD (an analog Position Sensitive Detector) sensor readings for target positions and the joint commands to reach them. Using this configuration, the system can track or follow a moving or stationary object in real time. Furthermore, an efficient neural network architecture has been developed for real time learning. This network uses multiple sets of simple backpropagation networks one of which is selected according to which division (corresponding to a cluster of the self-organizing feature map) in data space the current input data belongs to. This lends itself to a very training and processing implementation required for real time control.

• 한국산업융합학회 논문집
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• 제7권2호
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• pp.167-172
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• 2004

Neural networks are used in the framework of sensor based tracking control of robot manipulators. They learn by practice movements the relationship between PSD(an analog Position Sensitive Detector) sensor readings for target positions and the joint commands to reach them. Using this configuration, the system can track or follow a moving or stationary object in real time. Furthermore, an efficient neural network architecture has been developed for real time learning. This network uses multiple sets of simple back propagation networks one of which is selected according to which division (Corresponding to a cluster of the self-organizing feature map) in data space the current input data belongs to. This lends itself to a very training and processing implementation required for real time control.

• Journal of Acupuncture Research
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• 제18권2호
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• pp.186-199
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• 2001

Objectives : Sa-am Acupucture(舍岩鍼法), Taeguk Acupucture(太極鍼法), and 8 Constitution-Acupuncture(八體質鍼法) are largely used acupuncture therapies which utilize Yin and Yang, The Five Elements, Interpromoting and Counteracting Relation(相生 相克 關係). We are here to compare and study each acupuncture methods in order to understand their fundamental principle and theory. Conclusion : 1. When prescribing Herb to patients, we can use the Differentiation of Syndromes method(辨證論治). As there is Constitutional Medicine prescription(四象醫學處方) using constitutional Large & Small Relation of Jang and Bu organs(臟腑大小 關係), in acupuncture treatment we can use the Differentiation of Syndromes method of Sa-am acupucture, applying constitutional Large & Small feature of Jang and Bu organs(臟腑大小) in Taeguk Acupucture and 8 Constitution Acupuncture we can derive a suitable prescriptions. 2. Taeguk Acupucture and 8 Constitution Acupuncture is an acupunture method created upon the constitutional theory. Taeguk Acupucture lacks a theory and has problems with its practical use. 8 Constitution-Acupuncture has a theory, thus it can give us the chance to make derived diverse prescriptions for each diseases. 3. Sa-am Acupucture uses exclusively Manual technique(手技法), breathing Posa method(呼吸補瀉法), YoungSu Posa method(迎隨補瀉法) and also retaining method(留鍼法). Taeguk Acupunctune is directed related with WonBang Posa method(圓方補瀉法), twirling method(撚鍼法) and uses retaining method. 8 Constitution-Acupuncture works only with YoungSu Posa method and also One-insertion method(單刺法). 4. If we apply The Five Elements of five Su points and Interpromoting and Counteracting Relation(相生 相克 關係), we can control discords between Jang and Bu organs. Sa-am Acupucture, Taeguk Acupture and 8 Constitution Acupuncture which use five Su points can make better results in Jang and Bu organs disease. 5. Sa-am Acupunture needs diverse applications of Organ picture theory(臟象論), Pathogenesis theory(病機學說) and an proper prescription studies by Differentiation of Syndromes(辨證). Taeguk Acupuncture and 8 Constitution Acupuncture has a organized prescription methods by constitutional Large & Small relation of Jang and Bu organs(臟腑大小), thus we need to focus on objectification in constitutional differentiation.

• 대한방사선기술학회지:방사선기술과학
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• 제41권5호
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• pp.451-456
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• 2018

During last a decade, there has been increased demand for 3D-printed medical devices with significant improvement of 3D-Printer (also known as Additive. Manufacturing AM), which depend upon human body features. Especially, demand for personalized medical material is highly growing with being super-aged society. In this study, 3D-reconstructed 3D mesh image from CT/MRI-images is demonstrated to analyse each patients' personalized anatomical features by using in house, then to be able to manufacture its counterpart. Developed software is distributed free of charge, letting various researcher identify biological feature for each areas.