• Title/Summary/Keyword: dynamic performance analysis

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Wave Control by Bottom-Mounted and Fluid-Filled Flexible Membrane Structure (유체가 채워진 착저신 유연막 구조물에 의한 파랑제어)

  • 조일형;강창익
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.12 no.3
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    • pp.139-148
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    • 2000
  • In this paper, the interaction of oblique incident waves with a bottom-mounted and fluid-filled flexible membrane structure is investigated in the frame of linear hydro-elastic theory. The static shape of a membrane structure containing the fluid of a specific density is initially unknown and must be calculated before the hydrodynamic analysis. To solve hydrodynamic problem, the fluid domain is divided into the inner and outer region. The inner solution based on discrete membrane dynamic model and simple-source distribution over the entire fluid boundaries is matched to the outer solution ba~ed on an eigenfunction expansion method. The numerical results were compared to a series of Ohyama's experimental results. The measured reflection and tran¬smission coefficients reasonably follow the trend of predicted values. Using the computer program developed, the performance of a bottom-mounted and fluid-filled flexible membrane strocture is tested with various system parameters (membrane shape, internal pressure, density ratio) and wave characteristics (wave frequencies, incident wave angle). It is found that a bottom-mounted and fluid-filled flexible membrane structure can be an effel;tive wave barrier if properly designed.

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An Empirical Study on Effects of Global Alliance Activities on Alliance Innovations of Korean Companies (한국기업의 글로벌 제휴활동이 제휴혁신에 미치는 영향에 관한 실증연구)

  • Jeong, Jong-Sik
    • International Commerce and Information Review
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    • v.13 no.3
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    • pp.229-248
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    • 2011
  • The increasing complexity of business and social settings bas lead to innovation becoming a strategic imperative. The need for innovation in the quest for competitive advantage also means that firms must be dynamic and flexible. This is often achieved through collaborative arrangements such as strategic alliances or strategic network Many organizations form alliances by leveraging their resources to gain access to the partner's skills and capabilities; ultimately to enhance innovation and performance. We demonstrate empirically that the "chain of innovation" is central to the process of innovation in global alliances. This chain comprises the creativity and learning processes and knowledge stock in alliances. Our empirical analysis is based on a survey of alliances that resulted in 114 responses. For management, this research bas significant potential in guiding attention to the chain of innovation, to better manage the overall process of innovation in alliances. Our work shows that more effective creativity and learning processes and a greater knowledge stock lead to a more effective alliance innovation process. Managers therefore, need to concentrate on creating environments wherein the processes of creativity and learning are fostered, increasing the alliance knowledge stock and in turn, increasing innovative output via an effective innovation process.

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Effects of Welding Processes on the Low Temperature Impact Toughness of Structural Steel Welded Joints (용접방법에 따른 구조용강 용접 접합부의 저온 충격인성 특성)

  • Lee, Chin Hyung;Shin, Hyun Seop;Park, Ki Tae
    • Journal of Korean Society of Steel Construction
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    • v.24 no.6
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    • pp.693-700
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    • 2012
  • In this study, the Charpy impact test along with metallurgical observation was conducted to evaluate low temperature impact toughness of structural steel welds with different welding processes to find out the optimal welding process to guarantee the required impact toughness at low temperatures. The welding processes employed are shield metal arc welding (SMAW) and flux cored arc welding(FCAW), which are commonly used welding methods in construction. The Charpy impact test is a commercial quality control test for steels and other alloys used in the construction of metallic structures. The test allows the material properties for service conditions to be determined experimentally in a simple manner with a very low cost. To investigate the impact toughness at low temperatures of the steel welds, specimens were extracted from the weld metal and the heat affected zone. Standard V-notch Charpy specimens were prepared and tested under dynamic loading condition. The low temperature impact performance was evaluated based on the correlation between the absorbed energy and the microstructure. Analysis of the results showed that the optimal welding process to ensure the higher low temperature impact toughness of the HAZ and the weld metal is SMAW process using the welding consumable for steels targeted to low temperature use.

Implementation of Parallel Local Alignment Method for DNA Sequence using Apache Spark (Apache Spark을 이용한 병렬 DNA 시퀀스 지역 정렬 기법 구현)

  • Kim, Bosung;Kim, Jinsu;Choi, Dojin;Kim, Sangsoo;Song, Seokil
    • The Journal of the Korea Contents Association
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    • v.16 no.10
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    • pp.608-616
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    • 2016
  • The Smith-Watrman (SW) algorithm is a local alignment algorithm which is one of important operations in DNA sequence analysis. The SW algorithm finds the optimal local alignment with respect to the scoring system being used, but it has a problem to demand long execution time. To solve the problem of SW, some methods to perform SW in distributed and parallel manner have been proposed. The ADAM which is a distributed and parallel processing framework for DNA sequence has parallel SW. However, the parallel SW of the ADAM does not consider that the SW is a dynamic programming method, so the parallel SW of the ADAM has the limit of its performance. In this paper, we propose a method to enhance the parallel SW of ADAM. The proposed parallel SW (PSW) is performed in two phases. In the first phase, the PSW splits a DNA sequence into the number of partitions and assigns them to multiple nodes. Then, the original Smith-Waterman algorithm is performed in parallel at each node. In the second phase, the PSW estimates the portion of data sequence that should be recalculated, and the recalculation is performed on the portions in parallel at each node. In the experiment, we compare the proposed PSW to the parallel SW of the ADAM to show the superiority of the PSW.

Performance Analysis of Interworking Model for a Broadband Access Network with VB5.2 Interface (광대역 액세스 망의 VB5.2 인터페이스를 위한 연동 모델의 성능분석)

  • Kim, Choon-Hee;Cha, Young-Wook;Han, Ki-Jun
    • Journal of KIISE:Information Networking
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    • v.27 no.2
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    • pp.237-246
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    • 2000
  • A broadband access network in B-ISDN subscriber network, plays a role of concentration or multiplexing of various subscribers into a service node. For call and connection control functions, DSS2 and B-ISUP signalling protocols are standardized for each of a subscriber side and a network node. B-BCC and B-ANCC protocol were proposed for VB5.2 interface. This interface allows dynamic control of ATM connections at the broadband access network. To establish an end-to-end ATM connection, interworking functions between VB5.2 interface's connection control protocol and the signalling protocol, are performed at the service node. A sequential interworking model and a parallel interworking model were proposed for these interworking functions. The sequential interworking model recommended by ITU-T causes an overall connection setup delay by introducing the access network, because this model proceeds the signalling protocol of network node after the response of VB5.2 interface protocol. On the other hand, the parallel interworking model proceeds the signalling protocol and the VB5.2 interface protocol simultaneously. The simultaneity of the parallel interworking model minimizes the overall connection setup delay. In this paper, we analyze and simulate above two interworking models with B-BCC or B-ANCC protocol in terms of a connection setup delay and completion ratio.

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5GHz Wi-Fi Design and Analysis for Vehicle Network Utilization (차량용 네트워크 활용을 위한 5GHz WiFi 설계 및 분석)

  • Yu, Hwan-Shin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.8
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    • pp.18-25
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    • 2020
  • With the development of water internet technology, data communication between objects is expanding. Research related to data communication technology between vehicles that incorporates related technologies into vehicles has been actively conducted. For data communication between mobile terminals, data stability, reliability, and real-time performance must be guaranteed. The 5 GHz Wi-Fi band, which is advantageous in bandwidth, communications speed, and wireless saturation of the wireless network, was selected as the data communications network between vehicles. This study analyzes how to design and implement a 5 GHz Wi-Fi network in a vehicle network. Considering the characteristics of the mobile communication terminal device, a continuous variable communications structure is proposed to enable high-speed data switching. We simplify the access point access procedure to reduce the latency between wireless terminals. By limiting the Transmission Control Protocol Internet Protocol (TCP/IP)-based Dynamic Host Configuration Protocol (DHCP) server function and implementing it in a broadcast transmission protocol method, communication delay between terminal devices is improved. Compared to the general commercial Wi-Fi communication method, the connection operation and response speed have been improved by five seconds or more. Utilizing this method can be applied to various types of event data communication between vehicles. It can also be extended to wireless data-based intelligent road networks and systems for autonomous driving.

Direction-Embedded Branch Prediction based on the Analysis of Neural Network (신경망의 분석을 통한 방향 정보를 내포하는 분기 예측 기법)

  • Kwak Jong Wook;Kim Ju-Hwan;Jhon Chu Shik
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.42 no.1
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    • pp.9-26
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    • 2005
  • In the pursuit of ever higher levels of performance, recent computer systems have made use of deep pipeline, dynamic scheduling and multi-issue superscalar processor technologies. In this situations, branch prediction schemes are an essential part of modem microarchitectures because the penalty for a branch misprediction increases as pipelines deepen and the number of instructions issued per cycle increases. In this paper, we propose a novel branch prediction scheme, direction-gshare(d-gshare), to improve the prediction accuracy. At first, we model a neural network with the components that possibly affect the branch prediction accuracy, and analyze the variation of their weights based on the neural network information. Then, we newly add the component that has a high weight value to an original gshare scheme. We simulate our branch prediction scheme using Simple Scalar, a powerful event-driven simulator, and analyze the simulation results. Our results show that, compared to bimodal, two-level adaptive and gshare predictor, direction-gshare predictor(d-gshare. 3) outperforms, without additional hardware costs, by up to 4.1% and 1.5% in average for the default mont of embedded direction, and 11.8% in maximum and 3.7% in average for the optimal one.

Study on Geometric Figures on Body -Body Art- (신체에 표현된 기하학적 형태에 관한 연구 -바디아트 중심으로-)

  • 임미연
    • Journal of the Korea Fashion and Costume Design Association
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    • v.5 no.2
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    • pp.75-91
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    • 2003
  • This study analyzed descriptions about dots, lines, and sides which are used as a basic elements to express geometric figures as followings: -In the aspect of formative art, dots form images and feelings through their concurrence when make a slight move to coordinates. The concurrence can bring out either positive or negative images; -Lines have unlimited variation as a core measure in body art. They can make optimal effects with different lines such as straight and curved lines of human body; -Sides express not only effects of texture and perspective but also of space and solid by color effects. Expressive characteristics and geometric shapes can be classified by tattoo, henna and body painting: First, colorful tattoos are favored by Caucasian and original tattoos are mostly used by yellow and colored races in the way of scarification to get decorative effects. Recently, a rapid cycle of fashion change in tattoo figures has developed a tentative method of tattooing and a variety of decoration methods. It has made it a lot easier to change a pattern of a tattoo. Tattoos are now popular among people because they no longer have to suffer from pains when they get their body tattooed for a long time. Since tattoos boast their unique beauty which consists of most dynamic and attractive images among the types of body art. It will be one of the most favored make-up methods in the nearest future. Second, geometric designs used in henna include crosses, dots, straight lines, triangles, date palms, and so on. Henna has been particularly loved as an instant decoration by the public since it gradually disappears as time goes on. Third, body painting enables to draw a three-dimensional effect because of its close relation with body movements in a limited space. Each individual will have a different feeling appealed in their body painting. Body painting has been applied to many different areas, especially to theatrical art using lights, music and performance altogether producing impromptu and experimental works. Unlike other arts such as painting, sculpture, visual and industrial arts, body painting has mobility. Since it is painted on a three-dimensional human body, it can bear originality expressing realistic objects or animals and strengthen creative functions using body lines. Moreover, geometric designs can be diversified by the sexes. As a result of analysis, geometric designs expressed in body art seemed to transcend expressions of beauty and turned out to be another way of decoration. Body art has also been used as a way to express visual integration and consolidation dynamically not by human instinct but by social changes. The needs for body art will grow as the future comes nearer and be recognized as a new and fresh value. Formative elements of geometric figures deliver visual impressions combined with human body and finally create more various types of body art in harmony of body lines.

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The Analysis and Design of Advanced Neurofuzzy Polynomial Networks (고급 뉴로퍼지 다항식 네트워크의 해석과 설계)

  • Park, Byeong-Jun;O, Seong-Gwon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.39 no.3
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    • pp.18-31
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    • 2002
  • In this study, we introduce a concept of advanced neurofuzzy polynomial networks(ANFPN), a hybrid modeling architecture combining neurofuzzy networks(NFN) and polynomial neural networks(PNN). These networks are highly nonlinear rule-based models. The development of the ANFPN dwells on the technologies of Computational Intelligence(Cl), namely fuzzy sets, neural networks and genetic algorithms. NFN contributes to the formation of the premise part of the rule-based structure of the ANFPN. The consequence part of the ANFPN is designed using PNN. At the premise part of the ANFPN, NFN uses both the simplified fuzzy inference and error back-propagation learning rule. The parameters of the membership functions, learning rates and momentum coefficients are adjusted with the use of genetic optimization. As the consequence structure of ANFPN, PNN is a flexible network architecture whose structure(topology) is developed through learning. In particular, the number of layers and nodes of the PNN are not fixed in advance but is generated in a dynamic way. In this study, we introduce two kinds of ANFPN architectures, namely the basic and the modified one. Here the basic and the modified architecture depend on the number of input variables and the order of polynomial in each layer of PNN structure. Owing to the specific features of two combined architectures, it is possible to consider the nonlinear characteristics of process system and to obtain the better output performance with superb predictive ability. The availability and feasibility of the ANFPN are discussed and illustrated with the aid of two representative numerical examples. The results show that the proposed ANFPN can produce the model with higher accuracy and predictive ability than any other method presented previously.

Structural Capacity of High Strength Steel Pipe Pile After Pile Driving (고강도 강관말뚝의 항타후 구조성능 분석)

  • La, SeungMin;Yoo, Hankyu
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.6C
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    • pp.251-258
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    • 2011
  • Steel pipe piles have been used as various deep foundation materials for a long time. Recent increase in steel material cost has made engineers reluctant in using it even with its good quality and ease of construction. Therefore when constructing with steel pipe pile, the decision to reuse the excessive pile length that is cut off from the designed pile head elevation after pile driving can be cost saving. This has caused many constructors to reuse the pile leftovers with new piles, but the absence of quantitative structural capacity behaviors of steel pipe pile after pile driving or appropriate countermeasures and standards in reusing steel pipe pile has resulted in wrong applications, pile structural integrity problems, inappropriate limitation of reusable pile length, etc. The structural performance analysis between a new pile and a pile that has undergone working state and ultimate state stress level during pile driving was performed in this research by means of comparing the results between the dynamic pile load test, tensile load test, charpy energy test and fatigue test for high strength steel of $440N/mm^2$ yield strength. Test results show that under working load conditions the yield strength variation is less than 2% and for ultimate load conditions the variation is less than 5% for maximum total blow count of 3000. The results have been statistically analyzed to check the sensitivity of each factors involved. From the test results, reusability of steel pipe pile lies not in the main pipe yield strength deviation but in the reduction of absorb energy, strength changes and quality control at the welded section, shape deformation and local buckling during pile driving.