• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.10 s.181
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• pp.2513-2519
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• 2000

Free vibration characteristics of an initially stressed CD/DVD disk, which is designed for increasing critical speeds of current optical disks, are analyzed using the Rayleigh-Ritz technique based on variational formulations. Natural frequencies of the new disk depend on membrane stresses caused by disk rotation as well as residual stresses imposed during the cooling process of the injection molding. Critical speeds are calculated for the various initial patterns of radial and circumferential stresses. Initially imposed tensile stresses increase the natural frequencies of all the vibration modes except zero nodal diameter mode, whose natural frequency is independent of circumferential stress. A new disk with initial tensile stress of 0.5MPa is shown to have its critical speed about 30 % higher than the current optical disk.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.3
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• pp.41-51
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• 1997

In this study, two types of the direct digital frequency synthesizers (DDFS) designed and implemented using 1.0.mu.m CMOS gatearray(SOG) technolgoies are interoduced. To analize the effect of the number of phase bits(L), address data bits(A), and DAC bits (D) on the output spectrums of the DDFSs, the NCO-based BCD-DDFS composed of L=24, A=14, and D=8, and the improved binary-DDFS composed of L=24, A=8, and D=10 have been studied. The chips have been designed with and without a noise shapper to reduce spurious noises due to phase truncation and reduced sine ROM in output spectrum.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.4 no.2
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• pp.55-62
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• 1990

I본 연구에서는 마이크로프로세서에 의한 3상 전파 제어정류기의 점호각 제어회로를 설계하였다. 제어회로는 8비트 마이크로프로세서, 점호신호 발생 ROM, Presettable카운터, N분주 카운터와 PLL IC 등으로 구성되어 있다. PLL 원리를 이용하여 주파수 체배회로를 구성하였기 때문에 점호각이 넓은 범위의 전원 주파수에서 제어될 수 있고 간단한 제어알고리즘으로 인해 처리시간이 줄어들므로 빠른 응답특성을 가질 수 있었다. 본 연구에서는 기본 동작원리와 회로의 동작 특성에 대하여 설명하였고 좋은 동작 특성을 실험을 통해서 확인하였다. 이러한 동작원리는 싸이클로컨버터, 3상 교류 전압 조정기, dc 서보제어기와 다른 제어 시스템 등에도 적용이 가능할 것으로 생각된다.

• Journal of the Korean Arthroscopy Society
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• v.1 no.1
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• pp.86-90
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• 1997

Good stability and complete range of motion should be the ultimate goal of a rehabilitation program after ACL reconstruction. In previous years. the rehabilitation of the ACL reconstructed knee focused on protecting the new ligament by blocking terminal knee extension, hut, despite good stability, this approach led to numerous postoperative complications. Nowadays, most of surgeons agree the accelerated rehabilitation program based on the concept of ligamentization and clinical experience. Accelerated rehabilitation program consists of maintain of full extension of the knee, early weight bearing and prompt recovery of ROM, and closed kinetic chain exercise. Meeting this goal requires effective communication between-members of the health care team-the physician, physical therapist, atheletic trainer, and the patient. We have to know the importance of rehabilitation, knowlege about the physical therapy, and to introduce for special physical therapist and equipment.

• Korean Journal of English Language and Linguistics
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• v.3 no.4
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• pp.589-609
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• 2003

The purpose of this paper is to show that lexical equivalency in translation can be achieved when it is based on semantic prosodies of lexical items. This paper examines the semantic prosodies of two seemingly synonymous English adjectives ‘empty’ and ‘blank’ on the basis of the corpus given in Cobuild English Collocations on CD-ROM and proposes that they are different in terms of spatial dimensions. Thus when a Korean equivalent pin derived from the verb pita is translated into English, syntagmatic phraseological environments of the Korean adjective must be taken into account to attain the equivalency of the source and target languages. Relevant Korean corpus was taken from the 21st Century Sejong Plan (2002). Out of 12 examples of pin konggan, five appear to be equivalent to ‘blank’ and seven to ‘empty.’ The five to seven ratio in different usage indicates that the equivalency problem concerning the lexical item pin is not a trivial matter in translation.

• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.914-918
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• 2000

In this paper, a next generation high speed QPSK transmitter is designed based on 1.8${\mu}$m design rule. The designed transmitter supports the MPEG2-TS coded packed data for the DAVIC standard. Transmitter is composed of the convolutional coder, the shortened Reed-Solomon coder, and QPSK modulator. The coded packets are modulated in APSK with an RC filter. Especially, Galois Field multiplier with a standard basis is designed with the pipelined parallel architecture. Also, in the QPSK modulator, the RC filter and mixer are simplified into the ROM table, which can improve the performance of the transmitter. The total number of gates for the implemented baseband transmitter is 26,875.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.2
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• pp.86-93
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• 2004

The DCT algorithm needs an efficient hardware architecture to compute inner product. The conventional design method, like ROM-based DA(Distributed Arithmetic), has large hardware complexity. Because of this reason, a CSHM(Computation Sharing Multiplication) was proposed for implementing inner product by Park. However, the Park's CSHM has inefficient hardware architecture in the precomputer and select units. Therefore it degrades the performance of the multiplier. In this paper, we presents the optimization design method for inner product using CSHM algorithm and applied it to implementation of 1-D DCT processor. The experimental results show that the proposed multiplier is more efficient than Park's when hardware architectures and logic synthesis results were compared. The designed 1-D DCT processor by using proposed design method is more high performance than typical methods.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.05b
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• pp.832-835
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• 2003

전자책이란 저작물의 내용을 디지털 데이터로 CD-ROM, DVD 등 기록매체 또는 저장장치에 수록, 유·무선 통신망을 통해 전용 단말기나 컴퓨터로 이용할 수 있는 출판물을 의미한다. 전자책은 다양한 형태로(HTML, PDF, XML) 제작돼 표준이 없어 별도의 단말기를 개발 보급해야하는 문제와 함께 전자책 산업의 중복투자를 발생시켜 활성화에 어려움을 겪어왔다. 2002년 산업자원부 기술표준원은 이러한 문제를 해결하기 위해 상호운용성 등이 뛰어난 XML에 기반한 전자책 문서 표준(EBKS 1.0)안을 국가표준으로 제정하였다. 교육인적자원부에서도 2002년 '교과용 도서에 관한 규정' 을 개정, 주교재와 보완교재의 구분을 폐지해 음반이나 영상, 전자저작물 등을 활용한 전자교과서 및 지도서를 제작할 수 있도록 했다. 이러한 시대흐름에 발맞추어 본 연구에서는 XML Schema를 활용한 중학교 컴퓨터 과목의 전자교과서 문서 표준을 개발해 보고자 한다. EBKS를 비롯한 기존 연구의 대부분은 XML DTD를 이용한 표준 개발이 중심이었으나 DTD가 가진 제한점들로 인해 이미 XML Schema의 사용이 권고되고 있다.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.04a
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• pp.248-253
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• 2000

대용량의 연속 매체(continuous media)를 서비스하기 위한 멀티미디어 저장 서버는 실시간 검색과 대용량의 저장 장치 요구를 만족해야 한다. 그러나 기존에 연구되고 있는 디스크 배열(disk array)을 이용한 저장 서버는 성능 면에서 멀티미디어 응용에 바람직한 면이 있지만, 대규모 서버를 위한 저장 장치 전체를 디스크로 구성하는 것은 비용 면에서 비현실적일 뿐만 아니라 저장 용량과 대역폭에도 한계가 있다. 따라서 본 논문은 저가의 대용량 DVD-ROM을 사용한 계층적 저장 서버에서 파이프라인 로딩 기법을 제안한다. 제안된 기법은 시뮬레이션 성능분석을 통하여 파이프라인 상황하최대 허용 스트림 수가 크게 증가될 수 있음을 보인다.

• Journal of Acupuncture Research
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• v.23 no.5
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• pp.105-113
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• 2006

Objectives : To establish an effective collaborate medicine treatment of acupuncture and western medicine for treating frozen shoulder patients. Methods : 59 voluntary patients were randomly assigned to Eastern treatment group(E group, n=22), Western treatment group(W group, n=17) and East-West treatment group(EW group, n=20). The E group received acupuncture treatment on LI15, TE14, GB21 and Master Dong's acupuncture points, Shin-gwan and Gyun-joong, twice a week for 4 weeks. The W group received suprascapular nerve block, subacromial injection and trigger point injection, twice a week for 4 weeks. The EW group received acupuncture and injection treatment including nerve block All groups were instructed to practice self exercise during their daily lives. Evaluations were made before treatment and after treatment based on the change in shoulder Range of Motion(ROM) and the patient's satisfaction concerning the treatment was measured by Visual Analogue Scale(VAS). The obtained data were analyzed and compared. Results : The patient's satisfaction scores were E group 5.67, W group 7.73 and EW group 7.67. The E group and the EW group showed significant improvement in abbduction, adduction and flexion(p<0.05). The W group showed significant improvement in adduction(p<0.05). Abduction significantly improved(p<0.05) in the EW group compared to E group and W group. Flexion also showed improvement in the EW group, but the difference among the 3 groups was statistically insignificant. The three group's difference of change in extension and adduction was insignificant(p>0.05). Conclusion : Acupuncture and nerve block alone significantly improved ROM in frozen shoulder patients. Also collaborate treatment of acupuncture and nerve block significantly improved ROM in frozen shoulder patients. But the difference of the three treatments were significant only for improving abduction(p<0.05).