• Earthquakes and Structures
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• 제15권1호
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• pp.81-95
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• 2018

Most buildings feature core walls (and shear walls) that are placed eccentrically within the building to fulfil architectural requirements. Contemporary earthquake design standards require three dimensional (3D) dynamic analysis to be undertaken to analyse the imposed seismic actions on this type of buildings. A static method of analysis is always appealing to design practitioners because results from the analysis can always be evaluated independently by manual calculation techniques for quality control purposes. However, the equivalent static analysis method (also known as the lateral load method) which involves application of an equivalent static load at a certain distance from the center of mass of the buildings can generate results that contradict with results from dynamic analysis. In this paper the Generalised Force Method of analysis has been introduced for multi-storey buildings. Algebraic expressions have been derived to provide estimates for the edge displacement ratio taking into account the effects of dynamic torsional actions. The Generalised Force Method which is based on static principles has been shown to be able to make accurate estimates of torsional actions in seismic conditions. The method is illustrated by examples of two multi-storey buildings. Importantly, the black box syndrome of a 3D dynamic analysis of the building can be circumvented.

• 한국패류학회지
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• 제31권4호
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• pp.299-305
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• 2015

한국산 전복과 2속 2종 및 4아종 (N. gigantea, N. madaka, N. discus discus, N. discus hannai, S. diversicolor diversicolor, S. diversicolor supertexta)을 대상으로 주사전자현미경 (SEM)을 이용하여 치설 관찰을 하였다. 그 결과 전복과 패류의 치설형은 비대칭적인 선설형 (Rhipidoglossate form)이며, 치식 (Radular formula)은 >50-5-1-5-50< 으로 중앙에 1열의 중치와 3열의 측치 그리고 50열 이상의 연치로 구성되어 있다. 이러한 치설 구조는 실험 대상종 모두 공통적인 결과로 종 또는 속 간 치설 구조의 차이는 나타나지 않았다. 그러나 각 종별 세부적인 치설 형태의 차이점은 인지되어, 이를 규명하기 위한 정밀하고 세밀한 관찰이 요구되었다.

• Earthquakes and Structures
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• 제9권1호
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• pp.145-171
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• 2015

Due to earthquakes, many structures suffered extensive damages that were attributed to the torsional effect caused by mass, stiffness or strength eccentricity. Due to this type of asymmetry torsional moments are generated that are imposed by means of additional shear forces developed at the vertical resisting structural elements of the buildings. Although the torsional effect on the response of reinforced concrete buildings was the subject of extensive research over the last decades, a quantitative index measuring the amplification of the shear forces developed at the vertical resisting elements due to lateral-torsional coupling valid for both elastic and elastoplastic response states is still missing. In this study a reliable index capable of assessing the torsional effect is proposed. The performance of the proposed index is evaluated and its correlation with structural response quantities like displacements, interstorey drift, base torque, shear forces and upper diaphragm's rotation is presented. Torsionally stiff, mass eccentric single-story and multistory structures, subjected to bidirectional excitation, are considered and nonlinear dynamic analyses are performed using natural records selected for three hazard levels. It was found that the proposed index provides reliable prediction of the magnitude of torsional effect for all test examples considered.

• Structural Engineering and Mechanics
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• 제26권4호
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• pp.459-477
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• 2007

A bi-directional tuned mass damper (BTMD) in which a mass connected by two translational springs and two viscous dampers in two orthogonal directions has been introduced to control coupled lateral and torsional vibrations of asymmetric building. An efficient control strategy has been presented in this context to control displacements as well as acceleration responses of asymmetric buildings having asymmetry in both plan and elevation. The building is idealized as a simplified 3D model with two translational and a rotational degrees of freedom for each floor. The principles of rigid body transformation have been incorporated to account for eccentricity between center of mass and center of rigidity. The effective and robust design of BTMD for controlling the vibrations in structures has been presented. The redundancy of optimum design has been checked. Non dominated sorting genetic algorithm (NSGA) has been used for tuning optimum stages and locations of BTMDs and its parameters for control of vibration of seismically excited buildings. The optimal locations have been observed to be reasonably compact and practically implementable.

• Journal of Photoscience
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• 제8권3_4호
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• pp.87-92
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• 2001

Intramolecular excimer formation of 1,3-di(1-pyrenyl)propane (Py-3-Py) and fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) were used to investigate the effects of parathyroid hormone (PTH) on the bulk bilayer fluidity of the plasma membrane vesicles isolated from cultured osteoblasts (OB-PMV). In a dose-dependent manner, rat PTH-(1-34) [rPTH-(1-34)] increased the excimer to monomer fluorescence intensity ratio (I'/I) of Py-3-Py and decreased the anisotropy (r) of DPH in OB-PMV. This indicates that PTH increased both the lateral and rotational diffusion of the probes in OB-PMY. Selective quenching of DPH fluorescence by trinitrophenyl groups was utilized to examine the transbilayer fluidity asymmetry of OB-PMV. The anisotropy, limiting anisotropy, and order parameter of DPH in the inner monolayer were 0.024, 0.032, and 0.062 greater than calculated for the outer monolayer of OB-PMY. Selective quenching of DPH fluorescence by trinitrophenyl groups was also utilized to examine the transbilayer effects of PTH on the fluidity of OB-PMV. rPTH-(1-34) had a greater fluidizing effect on the outer monolayer as compared to the inner monolayer of OB-PMV. Thus, it has been proven that PTH exhibits a selective rather than nonselective fluidizing effect within transbilayer domains of OB-PMV.

• Archives of Plastic Surgery
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• 제39권5호
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• pp.556-560
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• 2012

Zygomatic fractures are the second most common facial bone fractures encountered and treated by plastic surgeons. Stable fixation of fractured fragments after adequate exposure is critical for ensuring three-dimensional anatomic reduction. Between January 2008 and December 2010, 17 patients with zygomatic fractures were admitted to our hospital; there were 15 male and 2 female patients. The average age of the patients was 41 years (range, 19 to 75 years). We exposed the inferior orbital rim and zygomatic complex through a lateral brow, intraoral, and subciliary incisions, which allowed for visualization of the bone, and then the fractured parts were corrected using the Carroll-Girard T-bar screw. Postoperative complications such as malar asymmetry, diplopia, enophthalmos, and postoperative infection were not observed. Lower eyelid retraction and temporary ectropion occurred in 1 of the 17 patients. Functional and cosmetic results were excellent in nearly all of the cases. In this report, we describe using the Carroll-Girard T-bar screw for the reduction of zygomatic fractures. Because this instrument is easy to use and can rotate to any direction and vector, it can be used to correct displaced zygomatic bone more accurately and safely than other devices, without leaving facial scars.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권11호
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• pp.581-588
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• 2001

This paper presents theoretical and experimental study on the quality-factor of the laterally oscillated electrostatic microactuator, driven by a lateral repulsive-force generated by the asymmetry of planar electric field. The quality-factor of the repulsive-force microactuator using a creeping flow model of the ambient air is evaluated. By filling the simulation results of damping force, we evaluate the dimensionless damping force, $\alpha$, thereby obtaining an analytical damping force, F, in the form of $F=\mu\; \alphaUL,\; where\; \mu,$ U and L denote the air viscosity, the velocity and the characteristic length of the movable electrodes. The measured quality-factor increases from 12 to 13 for the DC bias voltage increased from 60V to 140v. The theoretical quality-factor estimated from the creeping flow model increases from 14.9 to 18.7. Characteristics of quality-factor of the repulsive-force microactuator have been discussed and compared with those of the conventional attractive-force microactuator.

• Clinical and Experimental Pediatrics
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• 제49권2호
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• pp.208-211
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• 2006

Dyke-Davidoff-Masson 증후군은 일측성 대뇌 반구의 위축과 동측의 대상성 골비대, 반대측의 편마비 등을 특징으로 하는 드문 신경질환이다. 본 증례는 17개월 남아가 좌측 국소적 경련외에 좌측 편마비 및 기타 발달지연을 동반한 경우이다. 당시 시행한 뇌 자기공명영상에서 우측 대뇌 반구의 진행성 위축과 뇌실 확장, 두꺼워진 두개관과 동측 전두부 부비동의 확장, 추체 접형골의 거상을 보였고 뇌 SPECT 촬영상에 우측 대뇌 반구의 위축 및 혈류감소를 보였다. 이 같은 소견들은 Dyke-Davidoff-Masson 증후군에 합당하여 이에 저자들은 본 증례를 문헌 고찰과 함께 보고한다.

• 국제물리치료학회지
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• 제11권3호
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• pp.2147-2154
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• 2020

Background: Improperly conducted exercise may lead to worsening of musculoskeletal complications. Such may worsen due to increased repetition and intensity during exercise. In addition, different responses may show different needs for training program. Objectives: To compare kinematics of symmetric concentric and eccentric motions during increased repetitions and intensities for men and women. Design: Quasi-randomized trial. Methods: A total of ten men and eleven women participated in this study. Concentric and eccentric motions of the lateral raises were observed for initial positions of abduction and adduction. Low and high exercise intensities were applied, and 15 repetitions were conducted for both intensities. Initial, 3 inbetween repetitions, and last repetition were recorded for comparisons. Results: The concentric or abduction motions showed no significant differences for all comparisons. However, eccentric or adduction motions showed greater significant differences as the exercise intensity increased for both men and women. Such significant differences were most prevalent during the first and last repetitions with greatest differences during the initial repetitions. Conclusion: Kinematic difference between men and women during increased repetitions and intensity indicate the need for more individualized exercise intervention and consideration between men and women. Individualized interventions may prevent exercise-induced postural abnormality and corresponding musculoskeletal dysfunction.

• 치과방사선
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• 제9권1호
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• pp.13-18
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• 1979

The purpose of this study was to investigate the radiographic images of Temporomandibular joint trouble patients. This study included 186 patients with the chief complaints of TMJ pain and dysfunction. Their age ranged from 17 to 68 years. All patients were identified in the department of Dental mary of College of Dentistry, Seoul National University, Apr. 1978 to Jun. 1979. The author has observed the radiographic variations of two positions of condylar head taken by modified transcranial oblique-lateral projection, which are one in centric occlusion and the other in 1 inch(2.54㎝) mouth open. The results were obtained as follows; 1. In centric occlusion, the distances and positional relationship between the summit of condylar head and the deepest point of articular fossa revealed more or less large variations; Normal range is of 37.9%, anterior displacement of 37.3% and posterior displacement of 22.6%. 2. In the horizontal movement of condylar heads when on 1 inch mouth open, it was revealed that normalrange was of 46.5%, anterior displacement of 12.3%, posterior displacement of 41. 1 %. 3. In the positional interrelationship of both condylar heads when on 1 inch mouth open, it was revealed that symmetry(71. 5%) occurred approximately 2.5 times as many as asymmetry. 4. In both centric occlusion and 1 inch mouth open, it was showed that almost all estimated figures were greater in male than in female, and in the horizontal movement of condylar head when on 1 inch open, it was showed that hypermobility was dominant in male and hypomobility in female.