• Structural Engineering and Mechanics
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• v.56 no.6
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• pp.939-957
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• 2015

In this paper, a new approach based on the continuum model is proposed to estimate the main cable tension force of suspension bridges from measured natural frequencies. This approach considered the vertical vibration of a main cable hinged at both towers and supported by an elastic girder and hangers along its entire length. The equation reflected the relationship between vibration frequency and horizontal tension force of a main cable was derived. To avoid to generate the additional cable tension force by sag-extensibility, the analytical solution of characteristic equation for anti-symmetrical vibration mode of the main cable was calculated. Then, the estimation of main cable tension force was carried out by anti-symmetric characteristic frequency vector. The errors of estimation due to characteristic frequency deviations were investigated through numerical analysis of the main cable of Taizhou Bridge. A field experiment was conducted to verify the proposed approach. Through measuring and analyzing the responses of a main cable of Taizhou Bridge under ambient excitation, the horizontal tension force of the main cable was identified from the first three odd frequencies. It is shown that the estimated results agree well with the designed values. The proposed approach can be used to conduct the long-term health monitoring of suspension bridges.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.6 s.107
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• pp.68-81
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• 2005

The styles of contemporary landscape design have diversified since the emergence of Postmodernism in landscape architecture. The diversification was mostly influenced by contemporary fine arts and architecture. This study examines the pluralistic development of Postmodern landscape design through the investigation of the influences from those sister arts. In this point of view, the main approaches of Postmodern landscape design are thought to be classified into three categories;'the formal abstract approach', 'the figurative approach' and 'the new picturesque approach'. The first category of the formal abstract approach was formulated with the concepts and vocabulary of Minimal Art and Installation Art. Its representative icons such as 'point grids' and 'stripes', and the main concepts such as the sense of 'flahess', 'expansion' and 'materiality' are mostly thought to be originated from these art forms. The second category of the figurative approach is characterised by the concepts and vocabulary of Pop Art and New Image Paintings. Its representative icons such as 'map' or 'figurative forms' and main concepts like the sense of 'reality', 'context' and 'symbolism' are mostly thought to be originated from these art forms. The third category of the new picturesque approach was formulated with the concepts and vocabulary of Land Art and Late Deconstructive Architecture. Its representative icons such as 'hybrid', 'layer' and 'fold', and the main concepts such as the sense of 'complexity', 'continuity' and 'reversibility' are thought to be originated from these art forms. The research shows that the main stream of contemporary landscape design seems to be gradually moving toward the second and third approach above, in step with the cultural orientation and the dynamism of contemporary urban life. Therefore, the study focused especially on the new picturesque approach which would be in greater need for coping with the hybrid culture today.

• Korean Journal of Human Ecology
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• v.3 no.2
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• pp.39-46
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• 2000

This research was to identify housing identity expressed on entrance features In Korean single detached houses. The data were collected from field study and content analysis method of 45 houses in Chonju city. The methods of observation, of measuring the size, of sketching. and of Photos of entrance feature in the single detached houses were used for this study. Results of this study were as follows. First. the height and the form both of main gate and of wall tended to be closed. In particular. the size of main gate tended to be shown off rather than having practical funtion. whereas the form of main gate were semi-opened and thus could not guaranteed privacy of the residents very well. Second, 53.3% of the direction of main entrance were found to be at right-an91e0 with main gate, which reflected the control needs of private life. Third. the balance of main gate and exterior was homogeneous, which expressed the increase of aethetic concern of exterior Finally. most of entrance approach were made of stones and bricks. This result indicated that the practical funtion of entrance approach was emphasized the emotional environment was not considered in building the entrance approach.

• KIEAE Journal
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• v.2 no.4
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• pp.3-10
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• 2002

The main purpose of this dissertation is to develop an integrated approach to sustainable housing development, which would be applied in both academic studios and professional practice. This approach is based upon the concept of sustainability encountered in the process of housing design efficiency. It is concerned with the basic identification of problems and needs, the setting of design goals, and the constraints under which the future design and construction will have to operate. The components of the research approach focus on: (1) the identification of main issues of sustainable architecture (2) the identification of the concept of sustainability as integrated approach for architectural design. (3) the analysis of context between the housing design and the main issues of sustainablility. (4) the identification of the concept of sustainable housing design. Based on these results, this paper suggested the concept of sustainable housing design as integrated approach.

• Journal of Korean Neurosurgical Society
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• v.61 no.2
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• pp.224-232
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• 2018

Objective : Cervical ossification of the posterior longitudinal ligament (OPLL) can be treated via anterior or posterior approach, or both. The optimal approach depends on the characteristics of OPLL and cervical curvature. Although most patients can be successfully treated by a single surgery with the proper approach, renewed or newly developed neurological deterioration often requires repeat surgery. Methods : Twenty-seven patients with renewed or newly developed neurological deterioration requiring salvage surgery for multi-segment cervical OPLL were enrolled. Ten patients (group AP) underwent anterior approach, and 17 patients (group PA) underwent posterior approach at the initial surgery. Clinical and radiological data from initial and repeat surgeries were obtained and analyzed retrospectively. Results : The intervals between the initial and repeat surgeries were $102.80{\pm}60.08months$ (group AP) and $61.00{\pm}8.16months$ (group PA) (p<0.05). In group AP, the main OPLL lesions were removed during the initial surgery. There was a tendency that the site of main OPLL lesions causing renewed or newly developed neurological deterioration were different from that of the initial surgery (8/10, p<0.05). Repeat surgery was performed for progressed OPLL lesions at another segment as the main pathology. In group PA, the main OPLL lesions at the initial surgery continued as the main pathology for repeat surgery. Progression of kyphosis in the cervical curvature (Cobb's angle on C2-7 and segmental angle on the main OPLL lesion) was noted between the initial and repeat surgeries. Group PA showed more kyphotic cervical curvature compared to group AP at the time of repeat surgery (p<0.05). Conclusion : The reasons for repeat surgery depend on the type of initial surgery. The main factors leading to repeat surgery are progression of remnant OPLL at a different segment in group AP and kyphotic change of the cervical curvature in group PA.

• Communications for Statistical Applications and Methods
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• v.16 no.3
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• pp.519-528
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• 2009

This paper deals with nonparametric estimation of discontinuous regression curve. Quite number of researches about this topic have been done. These researches are classified into two categories, the indirect approach and direct approach. The major goal of the indirect approach is to obtain good estimates of jump locations, whereas the major goal of the direct approach is to obtain overall good estimate of the regression curve. Thus it seems that two approaches are quite different in nature, so people say that the comparison of two approaches does not make much sense. Therefore, a thorough comparison of them is lacking. However, even though the main issue of the indirect approach is the estimation of jump locations, it is too obvious that we have an estimate of regression curve as the subsidiary result. The point is whether the subsidiary result of the indirect approach is as good as the main result of the direct approach. The performance of two approaches is compared through a simulation study and it turns out that the indirect approach is a very competitive tool for estimating discontinuous regression curve itself.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.27 no.1
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• pp.313-336
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• 2016

The study reviews theoretical and empirical research literature in information needs, seeking and uses in order to search for the most pertinent metatheories for studying information practices of the disadvantaged. The study examines the salient features and main theories/models of each cognitive, affective and social approach in the user-centered paradigm through analyzing prior information practices studies. While analyzing the main features of each cognitive, affective and social approach, the study points out the limitation of research using the cognitive and affective approaches to fail to theorize the relationship between individuals and complex and dynamic socio-cultural contexts in information practices. As an alternative, the study suggests using the social approach as a pertinent metatheory for understanding information practices of the disadvantaged who are entangled with myriad social contexts and issues. In order to verify the pertinence, the study examines the advantages of the social approach through analyzing both the main models related to everyday information practices under social constructionism and the main findings from information practices of the disadvantaged.

• Steel and Composite Structures
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• v.27 no.1
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• pp.13-25
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• 2018

The main objective of this study is to develop a dual approach for geometrically nonlinear finite element analysis of plane truss structures. The geometric nonlinearity is considered using the Total Lagrangian formulation. The nonlinear solution is obtained by introducing and minimizing an objective function subjected to displacement-type constraints. The proposed method can fully trace the whole equilibrium path of geometrically nonlinear plane truss structures not only before the limit point but also after it. No stiffness matrix is used in the main approach and the solution is acquired only based on the direct classical stress-strain formulations. As a result, produced errors caused by linearization and approximation of the main equilibrium equation will be eliminated. The suggested algorithm can predict both pre- and post-buckling behavior of the steel plane truss structures as well as any arbitrary point of equilibrium path. In addition, an equilibrium path with multiple limit points and snap-back phenomenon can be followed in this approach. To demonstrate the accuracy, efficiency and robustness of the proposed procedure, numerical results of the suggested approach are compared with theoretical solution, modified arc-length method, and those of reported in the literature.

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.175-181
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• 2012

Under unsaturated capacity conditions with balanced approach flows, roundabout gives less delay and queue length than existing signalized intersections; however, over capacity conditions with unbalanced approach flows(flow above 450 pcu/h/lane), roundabouts efficiency drops due to the short gap between entering vehicles and circulating vehicles. This study provides a roundabout Signal Metering transfer standard and operation method. In this study, a four-way-approach with one-lane roundabout is selected to compare the Signal Metering performance for the case of unbalanced flow conditions. The performance is evaluated by using SIDRA software in terms of average delay and queue length. The result shows that the Signal Metering provides substantial improvements for the case of total approach flow is 1,800~2,000 pcu/h in which the main approach flow ratio is 60~70% gives 30~40% less delay and 30~60% less queue length than normal roundabout operation. Also, it is approved that operational performance saving can be achieved when the Metered Approach is selected adjoining to the main approach in pair.

• The Journal of the Acoustical Society of Korea
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• v.14 no.1
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• pp.115-122
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• 1995

It is practical to taper the element (e.g., antenna or sensor) spacing with uniform weight rather than to taper the weights with uniform spacing. In a rectangular array, a triangular grid geometry of elements is more economical than a rectangular grid geometry in terms of reducing the number of elements. A space-tapering approach is proposed to improve the performance of a rectangular phased array with a triangular grid geometry of elements above a ground plane. The effects of space tapering on the main beam width and sidelobe level are discussed. It is shown that the proposed approach improves the sidelobe performance while the main beam width becomes a little broader.