• Journal of Digital Convergence
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• v.11 no.3
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• pp.279-284
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• 2013

Wireless access network section needs strong security which supports high data rate and mobility not to invade patient's privacy by exposing patient's sensitive biometric from automatic implantable device that is adapted to u-healthcare service. This paper builds test bed and performs assessment and measurement of security ability of WiMAX network to transmit and receive mobile patient's biometric by building WiMAX network in wireless access network not to expose paitne's biometirc at wireless access network section to the third person. Specially, this paper compares and assesses data security, MAC control message security, handover conection delay, and frame loss and bandwidth of ECDH at the layer of WiMAX security compliance, WiMAX MAC IPSec, and MAC.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.10
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• pp.77-83
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• 2008

In terms of saving costs, energy and materials, the weight of cars has been gradually reduced by optimizing design of structure, which also gives us good performance. In compliance with this, it should satisfy the lifetime of cars for 25 years under the operation. The purpose of this study is to evaluate the strength of fatigue using date from strain gauges attached carbody and bogie frame. This dynamic stress can be evaluated using S-N curve based on stress amplitude. Modified S-N curve by CORTON-DOLAN is used for more conservative and substantial evaluation. In addition, !he loadings itself of carbody and bogie frame are considered by calculating the rate of the differences which are occurred between empty car and fuiiy occupied car with passengers. Rainflow cycle counting method is applied to arrange the stress data for the modified S-N curve to predict lifetime of the materials. Conclusively the cumulative damages are not only calculated by Miner's Rule, but the safety factors are also determined by Goodman diagram.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.11
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• pp.114-125
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• 1997

This paper presents a method that automatically recognizes dimension sets from the mechanical drawings, and that classifies 6 types dimension sets according to functional purpose. In the proposed method, the object and closed-loop symbols are separated from the character-free drawings. Then object lines and interpretation lines are vectorized. And, after recognizing dimension sets(consistings of arrowhead, shape line, tail lines, extension lines, text-string, and feature control frame), we classify recognized dimension sets as horizontal, vertical, angular, diametral, radial, and leader dimension sets. Finally the proposed method converts classified dimension sets into AutoCAD data by using AutoLisp language. By using the methods of geometric modeling, the proposed method readily recognized and classifies dimension sets from complex drawings. Experimetnal results are presented, which are obtained by applying the proposed method to drawings drawn in compliance with the KS drafting standard.

• International Journal of Air-Conditioning and Refrigeration
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• v.10 no.1
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• pp.40-49
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• 2002

Floating fixed scroll adopted for tip sealing enhancement in a scroll compressor is always under the influence of tipping moment produced by internal gas forces. Unless the tipping moment is property compensated by some restoring moment, the fired scroll would suffer tipping movement, degrading the compressor performance. The condition on which the tipping movement of the fixed scroll can be suppressed has been investigated analytically. For no tipping movement, the floating fixed scroll should be suspended on the main frame at proper level. The upper limit of the stable suspension is the axial location of the o-rings adopted for a back pressure chamber sealing on the rear side of the fixed scroll, and the lower limit is the mid-height of the scroll wrap.

• Structural Engineering and Mechanics
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• v.3 no.5
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• pp.475-495
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• 1995

In the past, physical models have been proposed, in compliance with the concept of the compressive-force path, for the realistic design of various statically determinate structural concrete members. The present work extends these models so as to encompass indeterminate RC structural forms. Pilot tests conducted on continuous beams and fixed-ended portal frames have revealed that designing such members to present-day concepts may lead to brittle types of failure. On the other hand, similar members designed on the basis of the proposed physical models attained very ductile failures. It appears that, unlike current design approaches, the compressive-force path concept is capable of identifying those areas where failure is most likely to be triggered, and ensures better load redistribution, thus improving ductility. The beneficial effect of proper detailing at the point of contraflexure in an indeterminate RC member is to be noted.

• Journal of Wellbeing Management and Applied Psychology
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• v.2 no.1
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• pp.35-39
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• 2019

This paper presents two social and academic studies on the boundary between cultural production and consumption. The first line of the study on cultural omnivore analyzes the choice of heterogeneous audiences in the face of various cultural offerings. The second line is a study of market categories, which analyzes the responses of peer audiences to objects with different levels of category code compliance. As such, this paper developed a heterogeneous audience model to evaluate objects of different types. This allows us to consider two dimensions of cultural preference: diversity and orientation of selection. To this end, this paper proposes a new analytical frame work to map consumption behavior on these two dimensions. The results suggest that one type of target that values diversity and transformation is particularly resistant to those that span boundaries. We test this argument in the analysis of two large data sets on film and restaurant reviews. Overall, our findings can extend beyond cultural consumption. Outline variability of contextual individuals or individuals in the same situation can cross cultural boundaries even if they are not intentionally pursuing such hybridism.

• Journal of the Korea Concrete Institute
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• v.22 no.3
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• pp.381-388
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• 2010

In this study, characteristics of the seismic response of the non-earthquake resistant reinforced concrete (RC) frame were identified. The test building is designed to withstand only gravity loads and not in compliance with modern seismic codes. Smooth bars were utilized for the reinforcement. Members are provided with minimal amount of stirrups to withstand low levels of shear forces and the core concrete is virtually not confined. Columns are slender and more flexible than beams, and beam-column connections were built without stirrups. Through the modeling of an example RC frame, the feasibility of the fiber elementbased 3D nonlinear analysis method was investigated. Since the torsion is governed by the fundamental mode shape of the structure under dynamic loading, pushover analysis cannot predict torsional response accurately. Hence, dynamic response history analysis is a more appropriate analysis method to estimate the response of an asymmetric building. The latter method was shown to be accurate in representing global responses by the comparison of the analytical and experimental results. Analytical models without rigid links provided a good estimation of reduced stiffness and strength of the test structure due to bond-slip, by forming plastic hinges closer to the column ends. However, the absence of a proper model to represent the bond-slip poased the limitations on the current inelastic analysis schemes for the seismic analysis of buildings especially for those with round steel reinforcements. Thus, development of the appropriate bond-slip model is in need to achieve more accurate analysis.

• Journal of the Korean Society of Safety
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• v.13 no.4
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• pp.221-229
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• 1998

This study, with a view point to prevent accidents arising from steel structure, construction process, has taken an approach of reviewing related materials and construction safety guidelines, conducting questionnaire surveys and on field surveys. This study has also analyzed and classified accident cases and disclosed elements concerned with those accidents. A comparative analysis of the disclosed elements against the statutory provisions regarding industrial safety and it showed that strict observance of safety rules of the accident prevention measures in industrial safety standards will result in a decrease in accidents. It is concluded, however, that additional accident prevention measures, as suggested below, should be implemented for performing of more practical and positive accident prevention. 1) Thorough review and preparation at pre-working stage at sites : Such elements of fall preventing facilely as supporting ropes and steel fabrications for safety guard rails should be initially reflected on detailed drawings and shop drawings so that they can be installed in advance at fabricating plants. 2) Sets of steel frame stairs for work platform should be installed or secured with priority and temporary installation of such prefabricated platform as scaffolds should be installed in advance with those platform attached to the frame members on the ground whenever possible before they are lifted. 3) A decrease in the rate of accident by more than 10% on Tuesdays and Thursdays, has been shown from the accident analysis so schedule of construction process should consider possible weekday of high risk of accidents such as Tuesday and Thursday. 4) An array of systemized safety activities should be adopted, such as legal installation of safety facilities based on advance safety management plan, maintenance of safety for machinery and construction equipment, and strict compliance of safety rules by workers.

• Advances in aircraft and spacecraft science
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• v.1 no.3
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• pp.331-351
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• 2014

The paper presents the development of numerical models referred to a morphing actuated aileron. The structural solution adopted consists of an internal part made of a composite chiral honeycomb that bears a flexible skin with an adequate combination of flexural stiffness and in-plane compliance. The identification of such structural frame makes possible an investigation of different actuation concepts based on diffused and discrete actuators installed in the skin or in the skin-core connection. An efficient approach is presented for the development of aeroelastic condensed models of the aileron, which are used in sensitivity studies and optimization processes. The aerodynamic performances and the energy required to actuate the morphing surface are evaluated and the definition of a general energetic performance index makes also possible a comparison with a rigid aileron. The results show that the morphing system can exploit the fluid-structure interaction in order to reduce the actuation energy and to attain considerable variations in the lift coefficient of the airfoil.

• Smart Structures and Systems
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• v.21 no.6
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• pp.715-725
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• 2018

Truss-Z (TZ) is an Extremely Modular System (EMS). Such systems allow for creation of structurally sound free-form structures, are comprised of as few types of modules as possible, and are not constrained by a regular tessellation of space. Their objective is to create spatial structures in given environments connecting given terminals without self-intersections and obstacle-intersections. TZ is a skeletal modular system for creating free-form pedestrian ramps and ramp networks. The previous research on TZ focused on global discrete geometric optimization of the spatial configuration of modules. This paper reports on the first attempts at structural optimization of the module for a single-branch TZ. The internal topology and the sizing of module beams are subject to optimization. An important challenge is that the module is to be universal: it must be designed for the worst case scenario, as defined by the module position within a TZ branch and the geometric configuration of the branch itself. There are four variations of each module, and the number of unique TZ configurations grows exponentially with the branch length. The aim is to obtain minimum-mass modules with the von Mises equivalent stress constrained under certain design load. The resulting modules are further evaluated also in terms of the typical structural criterion of compliance.