• Journal of Oral Medicine and Pain
• /
• v.38 no.1
• /
• pp.29-34
• /
• 2013

Objective: All patients who have the disc displacement with reduction (DDwR) are always not progressive but some of them with significant catching or locking progress to disc displacement without reduction (DDw/oR). In this study, we suggest opening exercise therapy using Locking-free Appliance (LA) to be helpful to prevent progressive derangement. Methods: Retrospectively, a total 37 patients who received exercise treatment using LA was analyzed from January 2010 to December 2011. Patients had been instructed in proper exercise technique to practise for opening and closing of mouth wearing the appliance 30 times a day in locking-free position. Results: None of the patients took a turn for worse to DDw/oR (37 patients). The 16 patients (43.2%, locking-free group) of them could open their mouth without intermittent condylar locking. Measurement of data was analyzed using and Mann-Whitney test. There was no statistically significant difference for age, gender, presence of palpational pain, locking period, VAS quantitative pain score between locking-free group and locking group. Conclusions: In this study, some patients could open their mouth without intermittent locking and did not take a turn for worse to DDw/oR after opening exercise therapy with LA. Furthermore, LA had advantages which were short wearing time, low costs and minimizing patients' uncomfortable compared to conventional treatment method. This therapy can be more appropriate new treatment to prevent progress to DDw/oR.

• Structural Engineering and Mechanics
• /
• v.8 no.1
• /
• pp.19-26
• /
• 1999

Superior performance of field consistent eight-node hexahedron element in static bending problems has already been demonstrated in literature. In this paper, its performance in free vibration is investigated. Free vibration frequencies of typical test problems have been computed using this element. The results establish its superior performance in free vibration, particularly in thin plate application and near incompressibility regimes, demonstrating that shear locking, Poisson's stiffening and volumetric locking have been eliminated.

• Archives of Reconstructive Microsurgery
• /
• v.24 no.2
• /
• pp.68-74
• /
• 2015

Purpose: The reconstruction of femur and tibia defects following tumor resection remains a surgical challenge. The clinical outcome of free vascularized fibula graft (VFG) reconstruction with locking plate for massive femur and tibia defects of more than 10 cm that were secondary to skeletal tumor resection is reported. Materials and Methods: Thirteen patients with a mean follow-up of 3.3 years were reviewed. Seven patients received vascularized fibula grafts in the femur and six in the tibia. The mean bony defect of the femur and tibia was more than 10 cm and the length of the grafted fibula was more than 15 cm. All defects were stabilized with long locking plates. Results: All patients were free of disease at final follow-up; All VFGs were transferred successfully. All patients had a successful outcome with bony union. Stress fractures of the grafted fibula had occurred but the locking plate stabilized the fracture and healed until the last follow-up. All patients were able to walk without a brace after a mean of 9 months postoperatively. Conclusion: VFG with locking plate is a reliable reconstructive procedure for massive femur and tibia defects.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2011.04a
• /
• pp.238-241
• /
• 2011

Locking은 다중 스레드간의 경쟁 상태를 조절하기 위한 전통적인 메커니즘이다. 하지만 Locking을 사용할 경우, 공유 데이터에 대한 잠금(lock) 및 해제(unlock)에 따른 대기 시간(waiting time)이 발생하며, 이는 전체 시스템 성능을 저하시킨다. Wait-free 동기화는 이러한 전통적인 Locking의 비용을 줄이고자 하는 기법이다. Wait-free 동기화의 기본 아이디어는 공유 데이터 수정 시 복제본을 생성해 처리함으로써 잠금에 따른 대기시간을 제거하는 것이다. 따라서 Wait-free 동기화 기법에서는 복제본생성 이후의 메모리 해제가 가장 큰 비용을 차지한다. 이에 본 논문에서는 Wait-free 동기화 및 메모리 해제 기법과 관련하여 주요 이슈 및 기술 현황에 대한 분석을 실시하였다.

• Structural Engineering and Mechanics
• /
• v.11 no.2
• /
• pp.123-132
• /
• 2001

An improved version of the Element-free Galerkin method (EFGM) is presented here for addressing the problem of transverse shear locking in shear-deformable beams with a high length over thickness ratio. Based upon Timoshenko's theory of thick beams, it has been recognized that shear locking will be completely eliminated if the rotation field is constructed to match the field of slope, given by the first derivative of displacement. This criterion is applied directly to the most commonly implemented version of EFGM. However in the numerical process to integrate strain energy, the second derivative of the standard Moving Least Square (MLS) shape functions must be evaluated, thus requiring at least a $C^1$ continuity of MLS shape functions instead of $C^0$ continuity in the conventional EFGM. Yet this hindrance is overcome effortlessly by only using at least a $C^1$ weight function. One-dimensional quartic spline weight function with $C^2$ continuity is therefore adopted for this purpose. Various numerical results in this work indicate that the modified version of the EFGM does not exhibit transverse shear locking, reduces stress oscillations, produces fast convergence, and provides a surprisingly high degree of accuracy even with coarse domain discretizations.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.10 no.5
• /
• pp.653-662
• /
• 1999

In this paper, subharmonically injection locked oscillator(SILO) was designed and measured. SILO with series feedback was designed using Two Signal Method(TSM). The free-running oscillator frequency was 9.4 GHz with 6 dBm output power. In case of injection, the multiplied injected signal locked the free-running frequency. The locked signal output power was higher than any other spurious response at least 40 dB. The locking range was 220MHz (second subharmonic locking), 100 MHz(4th subharmonic locking), and phase noise was -111 dBc/Hz, -104 dBc/Hz at 100kHz offset, respectively.

• Structural Engineering and Mechanics
• /
• v.59 no.3
• /
• pp.503-526
• /
• 2016

In-plane and out-of-plane free vibration analysis of Timoshenko curved beams is addressed based on the isogeometric method, and an effective scheme to avoid numerical locking in both of the two patterns is proposed in this paper. The isogeometric computational model takes into account the effects of shear deformation, rotary inertia and axis extensibility of curved beams, and is applicable for uniform circular beams, and more complicated variable curvature and cross-section beams as illustrated by numerical examples. Meanwhile, it is shown that, the $C^{p-1}$-continuous NURBS elements remarkably have higher accuracy than the finite elements with the same number of degrees of freedom. Nevertheless, for in-plane or out-of-plane vibration analysis of Timoshenko curved beams, the NURBS-based isogeometric method also exhibits locking effect to some extent. To eliminate numerical locking, the selective reduced one-point integration and $\bar{B}$ projection element based on stiffness ratio is devised to achieve locking free analysis for in-plane and out-of-plane models, respectively. The suggested integral schemes for moderately slender models obtain accurate results in both dominated and non-dominated regions of locking effect. Moreover, this strategy is effective for beam structures with different slenderness. Finally, the influence factors of structural parameters of curved beams on their natural frequency are scrutinized.

• Structural Engineering and Mechanics
• /
• v.50 no.2
• /
• pp.181-199
• /
• 2014

Locking phenomenon is a mesh problem and can be staved off with mesh refinement. If the studier is not preferred going to the solution with increasing mesh size or the computer memory can stack over flow than using higher order plate finite element or using integration techniques is a solution for this problem. The purpose of this paper is to show the shear locking phenomenon can be avoided by increase low order finite element mesh size of the plates and to study shear locking-free analysis of thick plates using Mindlin's theory by using higher order displacement shape function and to determine the effects of various parameters such as the thickness/span ratio, mesh size on the linear responses of thick plates subjected to uniformly distributed loads. A computer program using finite element method is coded in C++ to analyze the plates clamped or simply supported along all four edges. In the analysis, 4-, 8- and 17-noded quadrilateral finite elements are used. It is concluded that 17-noded finite element converges to exact results much faster than 8-noded finite element, and that it is better to use 17-noded finite element for shear-locking free analysis of plates.

• Proceedings of the IEEK Conference
• /
• 1999.11a
• /
• pp.275-278
• /
• 1999

In this paper, Dual PFD(Phase Frequency Detector) with improved phase locking time is proposed. The proposed PFD consists of positive and negative edge triggered D flip-flop. In order to confirm the characteristics of proposed PFD, HSPICE simulations are performed using a 0.25${\mu}{\textrm}{m}$ CMOS process. As a result of simulations, the proposed PFD has a characteristic of fast phase locking time with dead zone free.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2002.04a
• /
• pp.35-42
• /
• 2002

In this paper, effective analysis of beam is studied using the RKPM in meshless methods. So, RKPM is extended for solving moderately thick and thin beam. General Timoshenko beam theory is used for formulation. Shear locking is the main difficulty in analysis of beam structures. The shear relaxation factor and corrected shear rigidity are introduced to overcome shear locking. Analysis results obtained reveal that RKPM using introduced methods Is free of locking and very effectively applicable to deeply as well as shallowly beams.