• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1614-1617
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• 2003

Actuator being used in the ship supplies engine with air. When actuator is out of order, engine is not operated. This out of order is due to fracture of piston or rotating of spindle in the case of plastic deformation of parallel part in locking plate. For this reason, locking plate must be guaranteed enough strength. Therefor in this paper, the effects of changes with the clearance of between spindle and parallel part, the contact height of parallel part and spindle, the side circle diameter of parallel part and the width of locking plate in the designated torque are investigated. The result of this investigation shows the relation between locking plate and spindle.

• 한국통신학회논문지
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• 제21권9호
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• pp.2362-2372
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• 1996

This paper deals with the design and development of an Injection-Locking Coupled Oscillators(ILCO), which functions like phase-shifter in the Active Intergrated Phased Array Antenna(AIPAA). This linear array 2-element ILCO consists of two Injection Locking Hair-pin Resonator Oscillators(ILHRO) and an unilateral amplifier. The first and second elements of the ILCO have same frequency tuning range but locking bandwidths of 11.5MHz and 14MHz respectively. A phase shift of .DELTA..PHI.=158.4.deg.(-78.0.deg. to 80.4.deg.) could be obtained inthe second element of ILCO when the first elementof the ILCO was in the reference locking mode(.DELTA..PHI.=0.deg.). When the ILCO is applied to the AIPAA, the predicted beam scanning angle value will be 38.4.deg.. Each ILCO gives good frequency stability and lower AM, FM, and PM noise charactheristics in the mutual coupling lockingmode. The ILCO can not only play a part as the phase shifter for the AIPAA but it can also be usedas the power combining device in the mm-wave frequency range and as a part of a T/R MMIC module.

• 한국공작기계학회논문집
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• 제15권6호
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• pp.121-126
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• 2006

Snap-fit is being used in manufacture of plastic products. Integral features using snap-fit are classified as locks, locators and enhancements. Locking features complete the process of attachment by providing physical interference to prevent separation. Looking feature pairs consist of two components, i.e., a flexible latch and a rigid catch and require particular care and attention for their selection. We can make several locking feature pairs by selecting latch and catch, but some parts restrict freedom of selection. Therefore, part designers must know the characteristic properties of generic locking feature forms as considering a specific design problem. In this paper, it has been presented about problem of small size products using locking feature and then introduced new locking feature applicable to small parts.

• Nuclear Engineering and Technology
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• 제55권12호
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• pp.4477-4490
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• 2023

Fuel locking mechanisms (FLMs) are essential in upward-flow research reactors to prevent accidental fuel separation from the core during reactor operation. This study presents a novel design concept for a remotely controlled plate-type nuclear fuel locking mechanism. By employing electromagnetic field analysis, we optimized the design of the electromagnet for fuel unlocking, allowing the FLM to adapt to various research reactor core designs, minimizing installation space, and reducing maintenance efforts. Computational flow analysis quantified the drag acting on the fuel assembly caused by coolant upflow. Subsequently, we performed finite element analysis and evaluated the structural integrity of the FLM based on the ASME boiler and pressure vessel (B&PV) code, considering design loads such as dead weight and flow drag. Our findings confirm that the new FLM design provides sufficient margins to withstand the specified loads. We fabricated a prototype comprising the driving part, a simplified moving part, and a dummy fuel assembly. Through basic operational tests on the assembled components, we verified that the manufactured products meet the performance requirements. This remote-controlled micro locking mechanism holds promise in enhancing the safety and efficiency of plate-type nuclear fuel operation in upflow research reactors.

• 대한전자공학회논문지
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• 제19권2호
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• pp.38-50
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• 1982

이 논문에서는 변형된 디지탈 Costas loop이라고 불리우는 새로운 형의 digital phase-locked loop(DPLL)을 제안하고 성능을 해석하였다. 제안된 DPLL의 주요 특성은 tan-1(·) 함수를 DPLL에 사용함으로써 phase error detector가 선형 특성을 갖게 되고, 따라서 mod-2π 선형 difference equation에 의해서 그 특성을 설명할 수 있다. 본 논문은 2부로 나뉘어져 1부에서는 먼저 제안된 시스템을 설명하고 잡음이 없는 경우 Phase plane방법에 의해서 1차와 2차 loop의 성능을 해석했다. 초기 조건에 관계없이 locking이 될 수 있는 locking 범위의 식을 유도하고, 경우에 따라서 일어날 수 있는 false lock 또는 oscillation 현상을 설명했다. 이론적인 모든 해석은 컴퓨터 시뮬레이션에 의해서 입증되었다. 논문의 2부에서는 잡음이 있을 경우에 제안된 DPLL의 성능을 해석하였다. Chapman-Kolmogorov 방정식을 사용하여 제안된 시스템의 phase error의 steady state probability density함수, mean 및 variance를 얻었다. 이 결과들은 제 2부에 게재 될 것이다.

• Clinics in Shoulder and Elbow
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• 제17권1호
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• pp.10-17
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• 2014

Background: The aim of this study was to assess the clinical outcomes after treatment of proximal humeral fractures with locking plates, and to determine which factors influence the clinical and radiological outcomes. Methods: Fifty six patients who were treated with locking plates for proximal humeral fractures and had been followed for more than 1 year were enrolled in this study. We performed functional evaluation using the Constant score and analyzed radiographic results. The following factors that may potentially influence the clinical outcomes were assessed: age, gender, type of fracture, presence of medial metaphyseal comminution, bone mineral density, anatomical reduction, restoration of medial mechanical support, and postoperative complications. Results: The mean Constant score was 70.1 points at the final follow-up. Female gender, 4-part fractures, AO type-C fractures, and fractures with medial metaphyseal comminution were associated with a poor clinical outcome. On the other hand, restoration of medial mechanical support and accurate anatomical reduction had a positive influence on clinical outcomes. Postoperative complications resulted in 3 patients (intra-articular screw perforation: 1 patient, varus deformity with screw loosening: 1 patient, nonunion: 1 patient). Conclusions: When treating proximal humeral fractures with locking plate fixation, following factors: a female gender, Neer type 4-part fracture, AO type C fracture, and medial metaphyseal comminution are important risk factors that surgeons should take into consideration. Factors that contribute to better clinical outcomes of operative treatment for humeral fractures are accurate anatomical reduction and restoration of medial mechanical support.

• 정보처리학회논문지D
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• 제8D권1호
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• pp.24-31
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• 2001

본 논문에서는 다단계 보안 데이터베이스에서 동시성 정도를 향상시키고, 보안 요구사항을 만족하는 향상된 트랜잭션 스케쥴링 프로토콜을 제안한다. 전통적인 직렬성 표기를 가진 두단계 잠금 기법을 다단계 보안 데이터베이스에 적용했다. 이타적 잠금기법은 기부라는 사상을 사용하여 트랜잭션이 더 잇아 그 객체를 요구하지 않을 때 다른 트랜잭션들이 그 객체를 로크할 수 있도록 미리 객체에 대한 로크를 해제함으로써 트랜잭션들의 대기시간을 줄이기 위해서 제안된 것이다. 확장형 이타적 잠금기법은 처음에 기부되지 않은 객체까지도 처리하는 좀 더 완화된 기법이다. 본 논문에서는 다단계 보안 데이터베이스에서 단기 트랜잭션의 기아현상을 최소화하도록 하였다. 본 프로토콜은 확장형 잠금 기법(XAL/MLS)을 기초로 하였으나, 새로운 방법인 다단계 보안 데이터베이스를 위한 양방향 기부 잠금 규약(2DL/MLS)으로 보안 여구와 동시성 제어를 동시에 만족한다. 제안된 프로토콜의 효율성은 실험의 결과로 확인되었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1131-1135
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• 2005

Since human is vulnerable to emotional, physical and environmental distractions, most human inspectors cannot sustain a consistent 8-hour inspection in a day specifically for small components like door locking levers. As an alternative for human inspection, presented in this study is the development of a machine vision inspection system (MVIS) purposely for door locking levers. Comprises the development is the structure of the MVIS components, designed to meet the demands, features and specifications of door locking lever manufacturing companies in increasing their production throughput upon keeping the quality assured. This computer-based MVIS is designed to perform quality measures of detecting missing portions and defects like burr on every door locking lever. NI Vision Builder software for Automatic Inspection (AI) is found to be the optimum solution in configuring the needed quality measures. The proposed software has measurement techniques such as edge detecting and pattern-matching which are capable of gauging, detecting missing portion and checking alignment. Furthermore, this study exemplifies the incorporation of the optimized NI Builder inspection environment to the pre-inspection and post-inspection subsystems.

• 한국산학기술학회논문지
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• 제11권5호
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• pp.1558-1563
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• 2010

본 논문에서는 생산 현장에서 작업자가 육안으로 하고 있는 자동차 부품의 전수(全數) 검사 방법을 대체하기 위한 머신 비전 시스템의 개발을 위한 검사알고리즘에 관한 연구이다. 생산 효율과 품질 향상을 위한 노력의 일환으로 플라스틱 압출 성형에서 생기는 여러 가지 불량품 유형을 PC를 기반한 머신 비전 시스템(Machine Vision System)을 구축하기에 앞서 생산된 부품을 실시간 검사하고 제품의 불량 유무를 판별하는 알고리즘을 개발하는 것이 본 연구의 목적이다. 검사방법에 사용된 소프트웨어는 NI-LabVIEW를 사용하였으며, LabVIEW Vision 이미지 함수를 사용하여 검사 프로그램을 개발하였다. 개발된 검사 알고리즘은 생산 부품의 실시간 검사에 적용 될 수 있으며, 검사 영역과 설정 값을 비전 시스템 운용자가 설정할 수 있도록 프로그램이 만들어져 검증되었다.

• Clinics in Shoulder and Elbow
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• 제21권4호
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• pp.220-226
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• 2018

Background: This study introduces a surgical technique with good clinical outcome useful in the treatment of osteoporotic displaced 3- or 4-part proximal humeral fractures. Methods: From May 2014 to February 2016, 16 patients with displaced 3- or 4-part proximal humeral fractures were treated by application of a locking plate with an endosteal strut allograft via a deltoid splitting approach with a minimum follow-up of 12 months. The allograft was inserted through a fractured gap of the greater tuberosity to support the humeral head and then fixed by a locking plate with meticulous soft tissue dissection to protect the axillary nerve. Surgical outcomes were evaluated by the American Shoulder and Elbow Surgeons (ASES) and visual analogue scale (VAS) scores, radiological imaging, and clinical examination. Fixation failure on radiographs was defined as a >$5^{\circ}$ loss of neck shaft angle (NSA) compared to that on an immediate postoperative radiograph. Avascular necrosis (AVN) of the humeral head was also evaluated. Results: In all cases, complete union was achieved. The ASES and VAS scores were improved to $85.4{\pm}2.1$ and $3.2{\pm}1.3$, respectively. Twelve patients (75.0%) had greater than a $5^{\circ}$ change in NSA; the average NSA change was $3.8^{\circ}$. Five patients (31.3%) had unsatisfactory ranges of motion exhibiting a <$100^{\circ}$ active forward flexion. No axillary nerve injuries or AVN were observed at the last follow-up. One patient was converted to reverse total arthroplasty due to severe pain and functional deficit. Conclusions: Minimally invasive fixation via a locking compression plate and an endosteal fibula strut allograft in Neer classification 3-or 4-part fractures with severe osteoporosis in elderly patients can achieve good clinical results.