• Journal of Industrial Technology
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• v.3
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• pp.103-116
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• 1983

Recent developments in multi-storey buildings for residential purpose have led to the extensive use of shear walls for the basic structural system. When the coupled shear wall system is used, joined together with cast-in-place concrete or mortar (or grout), the function of the continuous joints is a crucial factor in determining the safety of L.P. Precast concrete shear wall structures, because the function of the continuous joints(Vertical wall to wall joints) is to transfer froces from one element(shear wall panel) to another, and if sufficient strength and ductility is not developed in the continuous joints, the available strength in the adjoining elements may not be fully utilized. In this paper, the influence of the stiffness of vertical joints(wet vertical keyed shear joints) on the behaviour of precast shear walls is theoretically investigated. To define how the stiffness of the vertical joints affect the load carrying capacity of L.P.Precast concrete shear wall structure, the L.P.Precast concrete shear wall structure is analyzed, with the stiffness of the vertical joints varying from $K=0.07kg/mm^3$(50MN/m/m) to $K=1.43kg/mm^3$(1000MN/m/m), by using the continuous connection method. The results of the analysis shows that at the low values of the vertical stiffness, i.e. from $K=0.07kg/mm^3$(50MN/m/m) to $K=0.57kg/mm^3$(400MN/m/m), the resisting bending moment and shearing force of precast shear walls, the resisting shearing force of vertical joints and connecting beams are significantly affected. The detailed results of analysis are represented in the following figures and Tables.

• Journal of Environmental Impact Assessment
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• v.8 no.3
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• pp.1-11
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• 1999

This study was carried out to evaluate urban environmental structure in Taegu metropolitan region(TMR) with factor analysis, fuzzy set theory, geostatistic and geographic information system(GIS). The factor analysis could choose the representative one out of multiple variables and simplify the evaluation of the urban environmental structure. The fuzzy approach is an attempt to model an aspect of human thinking previously neglected; it starts from the premise that humans don't represent classes of objects as fully disjoint but rather as sets where transitions from membership to non-membership is gradual. The Geographic Information System(GIS) could connect attributes of factor scores derived from factor analysis to digital map by a method so called 'Spatial join'. The results obtained were as follows: Urbanization appearance was concentrated in the large cities, and this appearance was partial extremely, therefore, there has been a structural gap between urban area and agricultural area which was unified into the urban area. All inclinations didn't become worse after sudden urbanization. For example, suburban agriculture was developed as a large scale in the region near the large cities. Then it encouraged farmers in changing their old cultivating methods to the latest ones. But many districts in urban fringe had symptom of urbanization, the districts which were located between large cities have been developed gradually because of urban sprawl, and played a role in connecting each city. Therefore, due to the urbanization, forestry area and agricultural land, well conserved in the agricultural town, could be easily destroyed. In a different way with the urbanization of the Seoul metropolitan region, that of TMR was centralized upon the center of each city, and it was also very partial. But, because so many regions have the potentiality of urbanization, hereafter, the urbanization process in each region is likely to be different multifariously according to the urban management methods.

• Advances in Computational Design
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• v.3 no.3
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• pp.233-267
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• 2018

Conventional seismic design of concentrically braced frame (CBF) structures suggests that the gusset plate connecting a steel brace to beams and/or columns should be designed as non-dissipative in earthquakes, while the steel brace members should be designed as dissipative elements. These design intentions lead to thicker and larger gusset plates in design on one hand and a potentially under-rated contribution of gusset plates in design, on the other hand. In contrast, research has shown that compact and thinner gusset plates designed in accordance with the elliptical clearance method rather than the conventional standard linear clearance method can enhance system ductility and energy dissipation capacity in concentrically braced steel frames. In order to assess the two design methods, six cyclic push-over tests on full scale models of concentric braced steel frame structures were conducted. Furthermore, a 3D finite element (FE) shell model, incorporating state-of-the-art tools and techniques in numerical simulation, was developed that successfully replicates the response of gusset plate and bracing members under fully reversed cyclic axial loading. Direct measurements from strain gauges applied to the physical models were used primarily to validate FE models, while comparisons of hysteresis load-displacement loops from physical and numerical models were used to highlight the overall performance of the FE models. The study shows the two design methods attain structural response as per the design intentions; however, the elliptical clearance method has a superiority over the standard linear method as a fact of improving detailing of the gusset plates, enhancing resisting capacity and improving deformability of a CBF structure. Considerations were proposed for improvement of guidelines for detailing gusset plates and bracing members in CBF structures.

• Journal of Energy Engineering
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• v.26 no.3
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• pp.123-130
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• 2017

The district heating system has been successfully implemented with higher efficiency levels of energy production and reduction of carbon emissions during heat generation. Traditionally the system consisted of small number of production and demand sites, but, recently it has evolved into a network with large number of sites interconnected each other. By connecting multiple sites into a network, heat from low-cost production sites can be supplied to distant demand sites so as to lower the total operation cost. In this study, we simulate and analyze distict heating networks focused on critical links. a critical link is defined as a link in which capacity is fully utilized. If a newtork has critical links, then those cricial links become bottlenecks and it is difficult to improve the overall network efficiency.

• Journal of the Korean Institute of Gas
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• v.15 no.3
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• pp.47-52
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• 2011

The purpose of this paper analyzes and studies to seek the failure examples of electronic control actuators for engine in liquified petroleum gas vehicle. The first, it was verified phenomenon for intial starting damage and no-acceleration of engine because of occasionally fuel feeding interception by clogged of emergency cutting solenoid valve filter. The second, the contact resistance produced in the connecting part of engine control relay because of no fully surface contacting by processes and assembly badness. It was displayed phenomenon of re-starting badness. The actuator that idle speed control system was sticked inside because of intake-air decreasing by carbon deposit. As a result, it was verified the phenomenon of disharmony that repeated up and down the engine revolution.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.10
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• pp.3729-3749
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• 2021

At present, deep convolution network-based salient object detection (SOD) has achieved impressive performance. However, it is still a challenging problem to make full use of the multi-scale information of the extracted features and which appropriate feature fusion method is adopted to process feature mapping. In this paper, we propose a new adjacency auxiliary network (AANet) based on multi-scale feature fusion for SOD. Firstly, we design the parallel connection feature enhancement module (PFEM) for each layer of feature extraction, which improves the feature density by connecting different dilated convolution branches in parallel, and add channel attention flow to fully extract the context information of features. Then the adjacent layer features with close degree of abstraction but different characteristic properties are fused through the adjacent auxiliary module (AAM) to eliminate the ambiguity and noise of the features. Besides, in order to refine the features effectively to get more accurate object boundaries, we design adjacency decoder (AAM_D) based on adjacency auxiliary module (AAM), which concatenates the features of adjacent layers, extracts their spatial attention, and then combines them with the output of AAM. The outputs of AAM_D features with semantic information and spatial detail obtained from each feature are used as salient prediction maps for multi-level feature joint supervising. Experiment results on six benchmark SOD datasets demonstrate that the proposed method outperforms similar previous methods.

• Journal of the Korea Society for Simulation
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• v.19 no.3
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• pp.91-98
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• 2010

This paper is on the research result for analyzing the performance of GLORY(GLobal Resource management sYstem) used for Web Server Cluster system, which was developed at ETRI(Electronic and Telecommunication Research Institute). The paper includes the definition of Web Server Cluster System, the characteristics of the system, user oriented system performance, current performance enhancement methods, computer simulation model for GLORY and its experimental results for the performance of GLORY. GLORY is composed of 2048~1,000,000 units of PCs, and is used for Internet servers. From the results of the simulation experiments, we notice that GLORY has enough capacity to fully serve the appropriate level of Internet services. Also, the results show that Web server service time is longer than that for network transmission time but requires more DNS than expected, and that 100Mbps LAN is good enough for directly connecting Internet to the Web servers while not affecting the total system performance.

• PNF and Movement
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• v.22 no.1
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• pp.1-11
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• 2024

Purpose: The prevalent use of mobile devices may contribute to musculoskeletal disorders, such as forward head posture (FHP), among users. The measurement of the craniovertebral angle (CVA) using photographic images is frequently employed in assessing FHP. Although manual CVA measurement using photographic images is reliable in clinical settings, computer programs or mobile applications to support tele-physical therapy are not yet fully developed. Therefore, in the current study, we propose an automatic method for extracting CVA from photographic images of FHP subjects to facilitate tele-physical therapy. Methods: To develop the automatic CVA measuring computer program, photographic images were obtained from 10 FHP participants. The location information obtained from the markers attached to the tragus and the spinous process of the seventh cervical vertebra were used as coordinates. Using these coordinates, straight line 1 was generated by connecting the seventh spinous process of the cervical vertebra and the tragus, while straight line 2 was drawn parallel to the coordinate obtained from the seventh spinous process of the cervical vertebra. The arc tangent function was used to calculate the angle between the two straight lines. The automatic CVA measurement computer program utilizing photographic images was developed using MATLAB (ver. 2016b). Results: The results showed that the automatic CVA measurement computer program demonstrated stable repeatability and high accuracy. Conclusion: The proposed approach was able to automatically estimate the CVA using photographic images. The developed computer program can potentially be used for easier and more reliable clinical assessment of FHP.

• Journal of Veterinary Clinics
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• v.24 no.4
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• pp.622-626
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• 2007

A 1.6-year-old, intact male beagle dog was presented with three day history of odynophagia and anorexia. According to the history and radiographic findings, the patient was diagnosed with esophageal and gastric foreign body due to ingesting fishhooks. Gastroesophagoscopy revealed that one fishhook located in the thoracic esophagus cranial to the heart base and the other located in the cardia region were connected with a single fishing line. Gastrotomy was performed to remove the fishhook in the cardia region and to sever the connecting fishing line. After gastrotomy, endoscopic attempts to remove the esophageal fishhook with a three, five pronged endoscopic grasping forceps, and a biopsy were unsuccessful because the fishhook was embedded deeply in the mucosa membrane. A handmade cerclage wire(16G) shaped like a snare forceps was advanced into the esophagus while visualizing the fishhook endoscopically. The cerclage wire was used to hang and retract the foreign body. The fishhook was retracted orally, resulting in successful removal. Ten days after the operation, the patient fully recovered and was discharged.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.4
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• pp.331-339
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• 2013

LiDAR has been one of the widely used and important technologies for 3D modeling of ground surface and objects because of its ability to provide dense and accurate range measurement. The objective of this research is to develop a method for automatic detection and modeling of railroad power lines using high density LiDAR data and RANSAC algorithms. For detecting railroad power lines, multi-echoes properties of laser data and shape knowledge of railroad power lines were employed. Cuboid analysis for detecting seed line segments, tracking lines, connecting and labeling are the main processes. For modeling railroad power lines, iterative RANSAC and least square adjustment were carried out to estimate the lines parameters. The validation of the result is very challenging due to the difficulties in determining the actual references on the ground surface. Standard deviations of 8cm and 5cm for x-y and z coordinates, respectively are satisfactory outcomes. In case of completeness, the result of visual inspection shows that all the lines are detected and modeled well as compare with the original point clouds. The overall processes are fully automated and the methods manage any state of railroad wires efficiently.