• Title/Summary/Keyword: Lead Frame

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Assessment of non-prismatic beams having symmetrical parabolic haunches with constant haunch length ratio of 0.5

  • Yuksel, S. Bahadir
    • Structural Engineering and Mechanics
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    • v.42 no.6
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    • pp.849-866
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    • 2012
  • Single span historic bridges often contain non-prismatic members identified with a varying depth along their span lengths. Commonly, the symmetric parabolic height variations having the constant haunch length ratio of 0.5 have been selected to lower the stresses at the high bending moment points and to maintain the deflections within the acceptable limits. Due to their non-prismatic geometrical configuration, their assessment, particularly the computation of fixed-end horizontal forces (FEFs) and fixed-end moments (FEMs) becomes a complex problem. Therefore, this study aimed to investigate the behavior of non-prismatic beams with symmetrical parabolic haunches (NBSPH) having the constant haunch length ratio of 0.5 using finite element analyses (FEA). FEFs and FEMs due to vertical loadings as well as the stiffness coefficients and the carry-over factors were computed through a comprehensive parametric study using FEA. It was demonstrated that the conventional methods using frame elements can lead to significant errors, and the deviations can reach to unacceptable levels for these types of structures. Despite the robustness of FEA, the generation of FEFs and FEMs using the nodal outputs of the detailed finite element mesh still remains an intricate task. Therefore, this study advances to propose effective formulas and dimensionless estimation coefficients to predict the FEFs, FEMs, stiffness coefficients and carry-over factors with reasonable accuracy for the analysis and re-evaluation of the NBSPH. Using the proposed approach, the fixed-end reactions due to vertical loads, and also the stiffness coefficients and the carry-over factors of the NBSPH can be determined without necessitating the detailed FEA.

A Study on Extraction and its Storage method of Topological Information from Common 2-D CAD Using The Boundary-Representation Method (범용 2D MCAD 상에서 경계표현법을 이용한 위상 정보 추출 및 그 저장방식에 관한 연구)

  • Hong, Sang-Hoon;Han, Seong-Young;Kim, Yong-Yun
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.9
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    • pp.25-34
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    • 1999
  • In spite of the advance of 3D solid modeling technology, there are some distinct areas where 2D CAD S/W are still dominant, and more competent comparing with 3D CAD S/W. For example, in the manufacturing of 2D-shaped electrical parts, most related manufacturing tools have 2D geometric features by nature, and 3D solid models applied to these parts have substantial overheads. Nevertheless, most 2D CAD S/W have no topological inquiry services because they have no such information on their geometrical database inherently. Thus, it is needed to extract such information from 2D CAD database for developing more advanced application such as automated drafting/design S/W. In this paper, the extraction of topological information from 2D CAD has been performed in general way using concept of B-rep. A general extraction algorithm, data structure and meta file format for 2D topological object have been developed and successfully applied to the development of the automated lead frame die design system in Samsung Aerospace. it is also possible to provide a flexible, powerful topology-oriented functionality on any common 2D CAD S/W.

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Public Design of Bus Station for Cheongju City with Plant Container Function (녹지시설 개념을 적용한 청주시의 버스정류장 공공디자인)

  • Lee, Juheon;Lee, Aekyung;Kim, Yanghee
    • FLOWER RESEARCH JOURNAL
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    • v.18 no.4
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    • pp.323-327
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    • 2010
  • This design study was conducted to plan and propose the bus-station as the public design for Cheongju City. The study was provided other purposes which designed its function as plant container and revealed the brand identity of Cheongju City, Jikji. At planning stage, design plant container with motif from top roof of the Early Printing Museum of Cheongju. And planed it located on the top of facility. The facilities, with design factors that increase satisfaction, were planed through the analysis of user behavior. The narrow frame and transparent wall were intended to establish clear sight for its users or pedestrians on road. In order to harmonize with urban surroundings, decreased the fanciness of designed figure and used achromatic color as lead main color.

A Research on the reappearance of delamination and the characteristic of LED package by thermal shock test (열충격 시험을 통한 LED Package의 박리재현 및 특성에 관한 연구)

  • Jang, In-Hyeok;Lim, Houng-Woo
    • Journal of Applied Reliability
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    • v.13 no.3
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    • pp.207-216
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    • 2013
  • This paper, we classified LED failure mechanisms that occur due to the delamination and analyzed each of the mechanism that gives the LED PKGs the effect. Usually, the LED is composed of several materials which are LED chips, gold wire, phosphor, epoxy resin, adhesive, reflector and lead frame. These different materials are usually delaminated in trouble conditions which are huge temperature difference, hot and humid or mechanical shocked. When the components are delaminated, a luminance will be lost and moisture be absorbed easily, a thermal resistance be increased attendantly. In this paper, we experimented to investigate failure mechanism of the thermal resistance and failure mechanism of the decrease of luminance that occur due to the delamination. A thermal shock test was performed to reproduce this phenomena by subjecting samples to a cold-hot cyclling process between $-30^{\circ}C$(15min) and $110^{\circ}C$(15min). The samples were inspected at 200, 600 and 1,000 cycles. We measured feature of LED using the spatial analyzer, optical microscope, thermal resistance, photometer, scanning electron microscope (SEM). As a result, the progression of the crack and the thermal resistance and decrease in luminance are proportional to number of thermal shock.

Accuracy of incidental dynamic analysis of mobile elevating work platforms

  • Jovanovic, Miomir L.J.;Radoicic, Goran N.;Stojanovic, Vladimir S.
    • Structural Engineering and Mechanics
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    • v.71 no.5
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    • pp.553-562
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    • 2019
  • This paper presents the results of a study into the dynamic behaviour of a support structure of a mobile elevating work platform. The vibrations of the mechanical system of the observed structure are examined analytically, numerically, and experimentally. Within the analytical examination, a simple mathematical model is developed to describe free and forced vibrations. The dynamic analysis of the mechanical system is conducted using a discrete dynamic model with a reduced number of vibrational degrees of freedom. On the basis of the expression for the system energy, and by applying Lagrange's equations of the second kind, differential equations are derived for system vibrations, frequencies are determined, and the laws of forced platform vibration are established. At the same time, a nonlinear FEM model is developed and the laws of free and forced vibration are determined. The experimental and numerical part of the study deal with the examination of the real structure in extreme conditions, taking into account: the lowest eigenfrequency, forced actions that could endanger the general stability, the maximal amplitudes, and the acceleration of the work platform. The obtained analytical and numerical results are compared with the experiments. The experimental verification points to the adverse behaviour of the platform in excitation cases - swaying. In such a situation, even a relatively small physical force can lead to unacceptably high amplitudes of displacement and acceleration - exceeding the usual work values.

Automated Audiometry: A Review of the Implementation and Evaluation Methods

  • Shojaeemend, Hassan;Ayatollahi, Haleh
    • Healthcare Informatics Research
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    • v.24 no.4
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    • pp.263-275
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    • 2018
  • Objectives: Automated audiometry provides an opportunity to do audiometry when there is no direct access to a clinical audiologist. This approach will help to use hearing services and resources efficiently. The purpose of this study was to review studies related to automated audiometry by focusing on the implementation of an audiometer, the use of transducers and evaluation methods. Methods: This review study was conducted in 2017. The papers related to the design and implementation of automated audiometry were searched in the following databases: Science Direct, Web of Science, PubMed, and Scopus. The time frame for the papers was between January 1, 2010 and August 31, 2017. Initially, 143 papers were found, and after screening, the number of papers was reduced to 16. Results: The findings showed that the implementation methods were categorized into the use of software (7 papers), hardware (3 papers) and smartphones/tablets (6 papers). The used transducers were a variety of earphones and bone vibrators. Different evaluation methods were used to evaluate the accuracy and the reliability of the diagnoses. However, in most studies, no significant difference was found between automated and traditional audiometry. Conclusions: It seems that automated audiometry produces the same results compared with traditional audiometry. However, the main advantages of this method; namely, saving costs and increased accessibility to hearing services, can lead to a faster diagnosis of hearing impairment, especially in poor areas.

Seismic performance of non-ductile detailing RC frames: An experimental investigation

  • Hidayat, Banu A.;Hu, Hsuan-Teh;Hsiao, Fu-Pei;Han, Ay Lie;Pita, Panapa;Haryanto, Yanuar
    • Earthquakes and Structures
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    • v.19 no.6
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    • pp.485-498
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    • 2020
  • Non-ductile detailing of Reinforced Concrete (RC) frames may lead to structural failure when the structure is subjected to earthquake response. These designs are generally encountered in older RC frames constructed prior to the introduction of the ductility aspect. The failure observed in the beam-column joints (BCJs) and accompanied by excessive column damage. This work examines the seismic performance and failure mode of non-ductile designed RC columns and exterior BCJs. The design was based on the actual building in Tainan City, Taiwan, that collapsed due to the 2016 Meinong earthquake. Hence, an experimental investigation using cyclic testing was performed on two columns and two BCJ specimens scaled down to 50%. The experiment resulted in a poor response in both specimens. Excessive cracks and their propagation due to the incursion of the lateral loads could be observed close to the top and bottom of the specimens. Joint shear failure appeared in the joints. The ductility of the member was below the desired value of 4. This is the minimum number required to survive an earthquake with a similar magnitude to that of El Centro. The evidence provides an understanding of the seismic failure of poorly detailed RC frame structures.

A Study for Damping Application to Response-controlled Structure

  • Shinozaki, Yozo;Mogi, Yoshihiro;Ota, Masaaki;Yoshikawa, Hiroaki
    • International Journal of High-Rise Buildings
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    • v.10 no.2
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    • pp.149-164
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    • 2021
  • Most of high-rise buildings in Japan*1 are structure with damping systems recently. The design procedure is performance-based design (PBD), which is based on the nonlinear response history procedure (NRHP) using 2 or 3-dimentional frame model. In addition, hysteretic property of steel plates or velocity-dependent property of viscous dampers are common practice for the damping system. However, for the selection of damping system, the easy dynamic analysis of recent date may lead the most of engineers to focus attention on the maximum response only without thinking how it shakes. By nature, the seismic design shall be to figure out the action of inertia forces by complex & dynamic loads including periodic and pulse-like characteristics, what we call seismic ground motion. And it shall be done under the dynamic condition. On the contrary, we engineers engineers have constructed the easy-to-use static loads and devoted ourselves to handle them. The structures with damping system shall be designed considering how the stiffness & damping to be applied to the structures against the inertia forces with the viewpoint of dynamic aspect. In this paper we reconsider the role of damping in vibration and give much thought to the basic of shake with damping from a standpoint of structural design. Then, we present some design examples based on them.

The Effect of Oriental Art as an Interior Design for Urban Hotel Business Plan

  • HAN, Soomin
    • East Asian Journal of Business Economics (EAJBE)
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    • v.10 no.2
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    • pp.115-125
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    • 2022
  • Purpose - The quality of the hotel depends on the Oriental arts established. Customers tend to believe that high prices reflect the offered services. This research expounds on the effects of Oriental interior designs in the hospitality industry in enhancing hotel profitability, opportunities for development, and the growth of urban hotels. Research design, Data, and methodology - This study conducted the comprehensive literature analysis to obtain suitable contents about the effect of Oriental Art for Urban Hotel Business Plan. the literature analysis method systematically assesses the value of qualitative data. Resources are organized into groups using a coding frame. Result - The adoption of the Oriental arts in the interior designs in the hotel industry will lead to customer attraction, improved competitive advantage, customer loyalty, and the preservation of the societal values of culture. Therefore, the marketing practitioners should adopt oriental arts as an integral aspect of interior designs to enhance customer satisfaction Conclusion - Marketing practitioners also use the oriental arts to enhance customers' willingness to pay. This is because oriental arts serve as the cues that enable the consumers to feel that the hotel's products are of quality. When oriental arts are used in interior hotel designs, the customer's willingness to pay increases. Thus the firm's relationships with customers are boosted.

Video-based Stained Glass

  • Kang, Dongwann;Lee, Taemin;Shin, Yong-Hyeon;Seo, Sanghyun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.7
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    • pp.2345-2358
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    • 2022
  • This paper presents a method to generate stained-glass animation from video inputs. The method initially segments an input video volume into several regions considered as fragments of glass by mean-shift segmentation. However, the segmentation predominantly results in over-segmentation, causing several tiny segments in a highly textured area. In practice, assembling significantly tiny or large glass fragments is avoided to ensure architectural stability in stained glass manufacturing. Therefore, we use low-frequency components in the segmentation to prevent over-segmentation and subdivide segmented regions that are oversized. The subdividing must be coherent between adjacent frames to prevent temporal artefacts, such as flickering and the shower door effect. To temporally subdivide regions coherently, we obtain a panoramic image from the segmented regions in input frames, subdivide it using a weighted Voronoi diagram, and thereafter project the subdivided regions onto the input frames. To render stained glass fragment for each coherent region, we determine the optimal match glass fragment for the region from a dataset consisting of real stained-glass fragment images and transfer its color and texture to the region. Finally, applying lead came at the boundary of the regions in each frame yields temporally coherent stained-glass animation.