• Clinics in Shoulder and Elbow
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• v.24 no.3
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• pp.135-140
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• 2021

Background: We hypothesized in this study that the characteristics of retear cases vary according to surgeon volume and that surgical outcomes differ between primary and revision arthroscopic rotator cuff repair (revisional ARCR). Methods: Surgeons performing more than 12 rotator cuff repairs (RCRs) per year were defined as high-volume surgeons, and those performing fewer than 12 RCRs were considered low-volume surgeons. Of the 47 patients who underwent revisional ARCR at our clinic enrolled in this study, 21 cases were treated by high-volume surgeons and 26 cases by low-volume surgeons. In all cases, the interval between primary surgery and revisional ARCR, degree of "acromial scuffing," number of anchors, RCR technique, retear pattern, fatty infiltration, retear size, operating time, and clinical outcome were recorded. Results: During primary surgery, significantly more lateral anchors (p=0.004) were used, and the rate of use of the double-row repair technique was significantly higher (p<0.001) in the high- versus low-volume surgeon group. Moreover, the "cut-through pattern" was observed significantly more frequently among the cases treated by high- versus low-volume surgeons (p=0.008). The clinical outcomes after revisional ARCR were not different between the two groups. Conclusions: Double-row repair during primary surgery and the cut-through pattern during revisional ARCR were more frequent in the high- versus low-volume surgeon groups. However, no differences in retear site or size, fatty infiltration grade, or outcomes were observed between the groups.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.237-243
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• 2002

A centrifugal compressor of 50HP for reverse brayton cryocooler using neon as a coolent has been developed. It has relatively low total-to-total pressure ratio but mass flow rate is very small and the voting gas, neon, has greater specific heat ratio than air. It was essential to have very high rotational speed of 100,000 RPM. The efficiency of compressor has great effects on overall system and the COP of cryocooler. To meet the design requirement of the compressor efficiency and to minimized the required rotational speed, highly efficiency impeller having low specific speed was designed. To maintain the overall system efficient high, gas bearing of bump type and high speed permanent magnet synchronus motor was developed and adopted. In this paper, design and performance prediction results of the compressor impeller is presented.

• Progress in Superconductivity and Cryogenics
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• v.13 no.3
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• pp.36-41
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• 2011

This paper describes experimental investigation on neon refrigeration system using commercial helium compressor. In this paper, neon refrigeration cycle is calculated with assumption of ideal heat exchanger. From analysis, 32.6 K of the lowest temperature and 0.945 of quality after expansion are predicted. Cryogenic heat exchangers for pre cooler and main heat exchanger are designed and fabricated with configuration of tube-in-tube heat exchanger. In experiments, cooling performance test are performed as variation of charging pressure and orifice hole diameter. From experimental results, the lowest temperature of 44.0 K was measured with 500 ${\mu}m$ orifice and 1500 kPa of charging pressure.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.8
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• pp.1266-1272
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• 2003

This paper presents a new class of magnetic microsensors based on the Hall effect in AC microplasma. In the theoretical study, we develop a simple model of the plasma Hall sensor and express the plasma Hall voltage as a function of magnetic field, plasma discharge field, pressure, and electrode geometry. On this basis, we have designed and fabricated magnetic microsensors using AC neon plasma. In the experiment, we have measured the Hall voltage output of the plasma microsensors for varying five different conditions, including the frequency and the magnitude of magnetic field, the frequency and the magnitude of plasma discharge voltage, and the neon pressure. The fabricated magnetic microsensors show a magnetic field sensitivity of 8.87${\pm}$0.18㎷/G with 4.48% nonlinearity.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.701-706
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• 2002

Typically, dimensions of the power circuit depend on magnetic components, heat sink, and smoothing capacitor, etc. For the miniaturization of the power circuit, one of the solutions is that bulky magnetic transformer in previously used is replaced by a piezoelectric transformer. Therefore, since many systems are attempted to apply the piezoelectric transformers, a new piezoelectric material is tending to be developed continuously. In this paper, an analysis of neon tube inverters with piezoelectric transformers are presented by Pspice modeling. Simulation results show that it is possible to apply a piezoelectric transformer to neon tube inverters with high conversion efficiency

• The Korean Journal of Soil Zoology
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• v.5 no.1
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• pp.13-19
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• 2000

This paper deals with four species of jumping spiders from Hunan province, China. Two new species; Philaeus daoxianensis sp. n. and Simaetha gongi sp. n., two new ones to China; Neon ningyo and Tasa davidi. Diagnostic structures, such as body and genitalia organs, are illustrated to each species. Descriptions and known data of geographical distribution also are given. In addition, detailed comparisons of the new species and its similar species are discussed. Type specimens are deposited in Department of Biology, Hunan Normal University, Changsha, Hunan, China.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06c
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• pp.344-346
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• 2012

스마트폰에서의 3D 게임/애플리케이션에 대한 사용자의 요구는 나날이 증가하고 있다. 3D 게임/애플리케이션은 내부적으로 $4{\times}4$ 행렬을 가지고 여러 가지 좌표 변환을 수행하기 때문에, 보다 빠른 3D 그래픽스 처리를 위해서는 $4{\times}4$ 행렬 연산의 최적화가 필수적이다. $4{\times}4$ 행렬 연산중에 역행렬 연산에 대해 살펴보고, ARM 프로세서에서 지원하는 Neon 연산자를 이용해서 $4{\times}4$ 행렬의 역행렬 연산을 개선할 수 있다.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.314-318
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• 1998

This paper discusses the development of electronic ballast for neon lamp as an application of a zero voltage switching high frequency inverter. Abnormal increase of secondary voltage due to grounded fault or partial damage of serial arranged loads is clarified and the protection circuit for this abnormal voltage increase is proposed. Also stable lighting condition for removing the unstable characteristics due to different load conditions is proposed.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2082-2084
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• 1998

This paper presents a microcontroller-based electronic neon ballasts which is highly suitable for a multi-use and low power consumption by performing economical hardwares and variable software algorithms. Result of this study has the following functions : brightness control, frequency variable output, automatic lightening control, low power characteristics.

• JOURNAL OF ELECTRICAL WORLD
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• no.8 s.140
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• pp.14-17
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• 1988