• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2002년도 춘계 학술발표회 논문집
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• pp.349-356
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• 2002

There has been an increasing trend toward the use of pushover analysis as a tool for evaluating the seismic resistant and safety of a building structure in the performance based earthquake engineering field. The ATC-40 document proposed a nonlinear static procedure based on the Capacity Spectrum Method to determine earthquake-induced demand given the structure pushover curve, which a curve representing base shear versus roof displacement. However, the procedure is conceptually simple, iterative and time consuming method and may sometimes lead to no solution or multiple solutions. A new improved method of seismic performance evaluation for moment frame building, which take into account the previously mentioned deficiencies of currently used elastic design procedures, is presented in this paper. The results of nonlinear static and nonlinear time history analysis of an example high-rise steel moment frame designed by the proposed method are presented and discussed.

• 대한산업공학회지
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• 제20권3호
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• pp.35-53
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• 1994

Orthographic views ore traditionally used for engineering drawings. This paper presents a methodology for 3D parametric design using orthographic views. The parametric design technique, which is used to design 2D orthographic views, is based on production rules. In the production rule-base, several view interrelation rules and over 50 geometric rules are included. An efficient algorithm is also developed to expedite the reasoning process. For 3D object construction from orthographic views, the approach known as bottom-up geometrical approach is used. The approach consists of 4 steps : 1) generation of wire-frame, 2) construction of face from wire frame, 3) formation of 3D subobjects from faces, and 4) construction of final 3D objects. Curvilinear solids as well as planar solids can be constructed. A method of converting existing 2D CAD data to parametric 3D CAD data is also presented.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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• pp.427-432
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• 1998

The objective of this research is to observe the actual response of low-rise nonseismic moment-resisting reinforced frame subjected to varied levels of earthquake ground motions. First of all, the reduction scale for the model was determined as 1 : 5 considering the capacity of the shaking table to be used. This model was, then, subjected to the shaking table motions simulating Taft N21E component earthquake ground motions, whose peak ground accelerations(PGA's) were modified to 0.12g, 0.2g, 0.3g, and 0.4g. The global behavior and failure mode were observed. The lateral accelerations and displacements at each story and local deformations at the critical portions of structure were measured. The base shear was measured by using specially made load cells. Before and after each earthquake simulation test, free vibration tests were performed to find the changes in the natural period and damping ratio of the model.

• Steel and Composite Structures
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• 제13권1호
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• pp.35-46
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• 2012

Implementation of openings in beams web has been introduced as an innovative method for improving seismic performance of steel moment frames. In this paper, several steel moment frames have been studied in order to evaluate the effect of openings in beams web. The beam sections with web opening have been modeled as a simplified super-element to be used in designing frames and to determine opening configurations. Finite element models of designed frames were generated and nonlinear static pushover analysis was conducted. The efficient location for openings along the beam length was discovered and the effects of beams with web openings on local and global behavioral characteristics of frames were discussed. Base on the results, seismic performance of steel moment frames was improved by creating openings in beams web, in terms of reduction in stress level of frame sensitive areas such as beam to column connections and panel zones.

• International Journal of Ocean System Engineering
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• 제1권2호
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• pp.102-109
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• 2011

This paper describes the implementation of a precise underwater navigation solution using a multiple sensor fusion technique based on USBL, GPS, DVL and AHRS measurements for the operation of a remotely operated mine disposal vehicle (MDV). The estimation of accurate 6DOF positions and attitudes is the key factor in executing dangerous and complicated missions. To implement the precise underwater navigation, two strategies are chosen in this paper. Firstly, the sensor frame alignment to the body frame is conducted to enhance the performance of a standalone dead-reckoning algorithm. Secondly, absolute position data measured by USBL is fused to prevent cumulative integration error. The heading alignment error is identified by comparing the measured absolute positions with the DR algorithm results. The performance of the developed approach is evaluated with the experimental data acquired by MDV in the South-sea trial.

• International Journal of Concrete Structures and Materials
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• 제7권2호
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• pp.135-153
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• 2013

This study investigates the direct displacement based design (DDBD) approach for different types of reinforced concrete structural systems including single moment-resisting, dual wall-frame and dual steel-braced systems. In this methodology, the displacement profile is calculated and the equivalent single degree of freedom system is then modeled considering the damping characteristics of each member. Having calculated the effective period and secant stiffness of the structure, the base shear is obtained, based on which the design process can be carried out. For each system three frames are designed using DDBD approach. The frames are then analyzed using nonlinear time-history analysis with 7 earthquake accelerograms and the damage index is investigated through lateral drift profile of the models. Results of the analyses and comparison of the nonlinear time-history analysis results indicate efficiency of the DDBD approach for different reinforced concrete structural systems.

• 대한수의학회지
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• 제35권2호
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• pp.287-295
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• 1995

Molecular cloning and nucleotide sequencing were undertaken for the RNA genome of gp53 antigenic region in cytopathic Singer strain of bovine viral diarrhea virus. The cloned cDNA was 939 nucleotides in length having a base composition of 31.0% A, 19.6% C, 25.5% G and 24.0% T. The sequence was corresponded to approximately 77.8%(817 bases) of predicted gp53 region and 122 bases after 3'end of gp53 region in the Singer strain when compared with NADL strain of known sequence. A single open reading frame was found in the sequence of 2nd frame and was deduced as encoding 312 amino acids.

• 한국공간구조학회논문집
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• 제10권2호
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• pp.69-76
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• 2010

적층고무 면진장치의 전단강성 뿐만 아니라 인장강성 및 압축강성을 실험적으로 구한 후 비선형 해석 프로그램을 이용하여 면진장치를 모델링 하였다. 수평력을 받는 면진된 골조의 면진장치에 전도에 의한 인장응력이 발생되게 하기 위하여 큰 초기변위를 부여한 자유진동 실험을 해석적으로 수행하였다. 적층고무 면진장치는 인장에 약하기 때문에 면진장치에서의 들림 현상을 해석적으로 구하기 위하여 면진장치의 수직방향 강성들이 해석 모델에 적절히 반영되어야 한다.

• Journal of Mechanical Science and Technology
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• 제18권12호
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• pp.2225-2235
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• 2004

An observatory termed 'Steel Swing' has been developed, where a 15000 kg pendulum is hanged from a stiff steel frame. A building element can be tested after inserted between the pendulum and the frame. Free vibration, forced vibration tests and earthquake monitoring were performed on an exposed-type steel column base. The response records monitored during natural earthquakes were used to identify the vibration property of the specimen. Identified system gain was approximated by a theoretical gain of linear SDOF system, and the response calculated based on such a linear system agrees with the monitored response fairly well. This research technique can be applied to check the behaviors of new materials and new details of connections and the safety of non-structural elements as well.

• 한국군사과학기술학회지
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• 제8권4호
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• pp.50-57
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• 2005

This paper describes an expert system for soldiers psychology diagnosis. In the field warfare, platoon leaders or company commanders have to diagnose his soldier's condition correctly. The expert systems, a field of artificial intelligence, can be appropriate approach for ill-structured paradigm. This use an UNIK system. This UNIK system is composed of UNIK-FRAME, UNIK-BWD, UNIK-WBI, UNIK-INDUCE and UNIK-Interface. Especially, UNIK-WBI system is very useful to display soldiers psychology diagnosis and so easy to use it. Any leader or commander can easily do this. This paper data is based on DSMIV. Through This expert system, combat power can be kept and accidents be protected.