• Title/Summary/Keyword: System-level design

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State Feedback Control of Container Crane using RCGA Technique (RCGA 기법을 이용한 컨테이너 크레인의 상태 피드백 제어)

  • Lee, Yun-Hyung;So, Myung-Ok;Yoo, Heui-Han;Cho, Kwon-Hae
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.399-404
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    • 2006
  • The container crane is one of the most important equipment in container terminal. If its working time in cycle could be reduced then container terminal efficiency and service level can be increased. So there are many efforts to reduce working time of container crane. It means how to design the controller with good performance which has small overshoot and swing motion of container crane. We, in this paper, present a state feedback controller not based on LQ theory but RCGA which means real-coded genetic algorithms. RCGA can search state feedback gains in given objective function. several cases of simulations are carried out in order to prove the control effectiveness of the proposed methods.

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Hydraulic Evaluation and Performance of On-Site Sanitation Systems in Central Thailand

  • Koottatep, Thammarat;Eamrat, Rawintra;Pussayanavin, Tatchai;Polprasert, Chongrak
    • Environmental Engineering Research
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    • v.19 no.3
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    • pp.269-274
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    • 2014
  • On-site sanitation systems are typically installed to treat grey and toilet wastewaters in areas without sewer and centralized treatment systems. It is well known that, due to inappropriate design and operation, treatment performance of these systems in developing countries is not satisfactory in the removal of pathogens and organic matters. This research aimed to investigate the hydraulic conditions occurring in some on-site sanitation systems and the effects of hydraulic retention times (HRTs) on the system performance. The experiments were conducted with a laboratory-scale septic tank (40L in size) and an actual septic tank (600L in size), to test the hydraulic conditions by using tracer study with HRTs varying at 12, 24 and 48 hr. The experimental results showed the dispersion numbers to be in the range of 0.017-0.320 and the short-circuit ratios in the range of 0.014-0.031, indicating the reactors having a high level of sort-circuiting and approaching complete-mix conditions. The removal efficiency of $BOD_5$ was found to be 67% and the $k_{30}$ values for $BOD_5$ was $2.04day^{-1}$. A modified complete-mix model based on the relationship between $BOD_5$ removal efficiencies and HRTs was developed and validated with actual-scale septic tank data having a correlation coefficient ($R^2$) of 0.90. Therefore, to better protect our environment and minimizing health risks, new generation toilets should be developed that could minimize short-circuiting and improving treatment performance.

Comparative Study of PI, FNN and ALM-FNN for High Control of Induction Motor Drive (유도전동기 드라이브의 고성능 제어를 위한 PI, FNN 및 ALM-FNN 제어기의 비교연구)

  • Kang, Sung-Jun;Ko, Jae-Sub;Choi, Jung-Sik;Jang, Mi-Geum;Back, Jung-Woo;Chung, Dong-Hwa
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2009.05a
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    • pp.408-411
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    • 2009
  • In this paper, conventional PI, fuzzy neural network(FNN) and adaptive teaming mechanism(ALM)-FNN for rotor field oriented controlled(RFOC) induction motor are studied comparatively. The widely used control theory based design of PI family controllers fails to perform satisfactorily under parameter variation nonlinear or load disturbance. In high performance applications, it is useful to automatically extract the complex relation that represent the drive behaviour. The use of learning through example algorithms can be a powerful tool for automatic modelling variable speed drives. They can automatically extract a functional relationship representative of the drive behavior. These methods present some advantages over the classical ones since they do not rely on the precise knowledge of mathematical models and parameters. Comparative study of PI, FNN and ALM-FNN are carried out from various aspects which is dynamic performance, steady-state accuracy, parameter robustness and complementation etc. To have a clear view of the three techniques, a RFOC system based on a three level neutral point clamped inverter-fed induction motor drive is established in this paper. Each of the three control technique: PI, FNN and ALM-FNN, are used in the outer loops for rotor speed. The merit and drawbacks of each method are summarized in the conclusion part, which may a guideline for industry application.

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User Authentication Mechanism of Ad-hoc Network (Ad Hoc망의 사용자 인증 메커니즘)

  • Lee, Cheol-Seung;Park, Do-Jun;Shin, Myung-Suk;Lee, Joon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2004.05b
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    • pp.713-716
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    • 2004
  • In this paper we challenge the user Authentication using Kerberos V5 authentication protocol in Ad-hoc network environment. Ad-hoc network is a collection of wireless mobile nodes without the support of a stationary infrastructure. and DSR routing protocol, which is one of famous mobile ad-hoc routing protocols, has the following network path problem. this paper is the security structure that defined in a mobile network and security and watches all kinds of password related technology related to the existing authentication system. It looks up weakness point on security with a problem on the design that uses Ad-hoc based structure and transmission hierarchical security back of a mobile network, and a server-client holds for user authentication of an application level all and all, and it provides one counterproposal.

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A Design of Context-Aware Middleware based on Web Services in Ubiquitous Environment (유비쿼터스 환경에서 웹 서비스에 기반한 상황 인식 미들웨어의 설계)

  • Song, Young-Rok;Woo, Yo-Seob
    • Journal of the Institute of Convergence Signal Processing
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    • v.10 no.4
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    • pp.225-232
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    • 2009
  • Context-aware technologies for ubiquitous computing are necessary to study the representation of gathered context-information appropriately, the understanding of user's intention using context-information, and the offer of pertinent services for users. In this paper, we propose the WS-CAM(Web Services based Context-Aware Middleware) framework for context-aware computing. WS-CAM provides ample power of expression and inference mechanisms to various context-information using an ontology-based context model. We also consider that WS-CAM is the middleware-independent structure to adopt web services with characteristic of loosely coupling as a matter of communication of context-information. In this paper, we describe a scenario for lecture services based on the ubiquitous computing e e e e e e to verify the utilization of WS-CAM We also show an example of middleware-independent system expansion to display the merits of web-based services. WS-CAM for lecture services represented context-information itodomaits as OWL-based ontology model effectively, and we confirmed the information is inferred to high level context-information by user-defined rules. We also confirmed the context-information is transferred to application services middleware-independently using various web methods provided by web services.

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Early Start Branch Prediction to Resolve Prediction Delay (분기 명령어의 조기 예측을 통한 예측지연시간 문제 해결)

  • Kwak, Jong-Wook;Kim, Ju-Hwan
    • The KIPS Transactions:PartA
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    • v.16A no.5
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    • pp.347-356
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    • 2009
  • Precise branch prediction is a critical factor in the IPC Improvement of modern microprocessor architectures. In addition to the branch prediction accuracy, branch prediction delay have a profound impact on overall system performance as well. However, it tends to be overlooked when the architects design the branch predictor. To tolerate branch prediction delay, this paper proposes Early Start Prediction (ESP) technique. The proposed solution dynamically identifies the start instruction of basic block, called as Basic Block Start Address (BB_SA), and the solution uses BB_SA when predicting the branch direction, instead of branch instruction address itself. The performance of the proposed scheme can be further improved by combining short interval hiding technique between BB_SA and branch instruction. The simulation result shows that the proposed solution hides prediction latency, with providing same level of prediction accuracy compared to the conventional predictors. Furthermore, the combination with short interval hiding technique provides a substantial IPC improvement of up to 10.1%, and the IPC is actually same with ideal branch predictor, regardless of branch predictor configurations, such as clock frequency, delay model, and PHT size.

Study on the Status Change in Rural Landscape Planning and Landscape Project in the General Agriculture Fishing Village Development Project (일반농산어촌개발사업에 있어 농촌경관계획과 경관사업부문의 위상변화에 관한 연구)

  • Lee, Su Hyun;Cho, Tong Buhm
    • Journal of Korean Society of Rural Planning
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    • v.25 no.4
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    • pp.119-128
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    • 2019
  • Although the General Agricultural Fishing Village Development Project had a significant impact on the landscape formation and management in rural area, the rural landscape planning and project sectors was not stable by fluctuation variables. On the basic understanding the institutional status of rural landscape planning, some conclusions could be discussed as follows through the analysis of quantitative and qualitative changes and the background factors. The rural landscape plan lacked its own legal and institutional foundations, and the landscape project of the General Agricultural Fishing Village Development Project was mainly focused on the environment-improving H/W project for expanding the basic living infrastructures. In order to reflect the characteristics of the region and become independent rural landscape management, it is necessary to change the contents so that the S/W business such as the deepening landscape awareness and empowerment linked with improving the physical landscape. To this end, it is necessary to establish a foundation for the rural landscape planning system to have its own status, and it seems to seek to supplement with what is included S/W contents reflecting the context of higher level landscape planning. The landscape sector of the General Agricultural Fishing Village Development Project proved to be in the process of shrinking in both quantity and quality, despite the temporary expansion in the past. In addition, considering the distortion of the contents of landscape projects in rural sites, it seems that the rural landscape-related public project are now in a position to seek a new phase change beyond quantitative expansion. In particular, along with institutional improvements to secure the independent status of rural landscape planning that contributes to village community regeneration and social sustainability through the role of intermediary support organizations in landscape management activities. Through the integrated landscape plan, which is established in advance and led by the residents in the early stages, there is a need to change the direction to enhance meaning of the landscape planning goes beyond the facility design or space improvement.

Estimation for Dynamic Deformation of the Cushioning Materials of Packaging for the Pears by Shock and Vibration During Transportation (유통 중 진동충격에 의한 배 포장 완충재의 동적 변위 추정)

  • Jung, Hyun-Mo;Park, In-Sig;Kim, Man-Soo
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.11 no.1
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    • pp.17-24
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    • 2005
  • During handling unitized products, they are subjected to a variety environmental hazards. Shock and vibration hazards are generally considered the most damaging of the environmental hazards on a product, and it may encounter while passing through the distribution environment. A major cause of shock damage to products is drops during manual handling. The increasing use of unitization on pallets has been resulted in a reduction in the manual handling of products and with it a reduction in the shock hazards. This has caused and increasing interest in research focused on vibration caused damage. the use of pallets as a base for unitizing loads, aids in the mechanical handling, transportation and storage of products. Besides aiding in the handling, transportation and storage of products, a pallet also acts on and interface between the packaged goods and the distribution environment. The determination of the impact deformation of the cushioning materials such as tray cup (polymeric foam) and corrugated fiberboard pad must be carried out to design the proper packaging system providing adequate protection for the fruit, and to understand the complex interaction between the components of fruit when they relate to expected transportation vibration inputs. In this study, the theoretical analysis of impact deformation for cushioning materials by dynamic vibration. The impact deformations of SW and DW corrugated fiberboard pad in acceleration amplitudes of 0.25 G-rms and 0.5 G-rms that were usually generated in transport vehicles during distribution environments were very small compare with the thickness of corrugated fiberboard pad. The maximum of vibration acceleration level of tray cup by vibration impact was about 3.2 G-rms. The theoretical allowable acceleration (G-factor) of the pear was 0.7102 G-rms, and the maximum dynamic deformation estimated within G-factor was about 1 mm.

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A Study on Friction Loss of Engine using Microfluidics Approach (미세유동의 경계면 특성을 적용한 엔진 마찰 손실 연구)

  • Park, Cho Hee;Kim, Bo Hung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.38 no.12
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    • pp.1035-1042
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    • 2014
  • Reducing the friction of engine parts is an important issue in engine design. The loss of energy in the piston assembly due to mechanical friction ranges from 40 to 55%, and there is an increase in the total energy of about 5% if the friction of the piston can be removed. In order to reduce the friction loss at the level of each engine part, it is necessary to perform a comparative analysis with other engines to determine the important factors affecting the energy loss. Several studies have been performed to analyze the lubrication based on hydrodynamic modeling, since a piston lubrication system has dimensions in the nanoscale to microscale domain. Therefore, it is necessary to determine the correlations between the molecular and continuum systems. In this study, we investigated the friction changes due to the various interactions between molecules in the wall/fluid interface, where a microscopic movement of the oil film occurs along the cylinder liner of the engine.

Design and Implementation of Domain Ontology to Overcome Conceptual Heterogeneity in Annotation-based Image Retrieval (주석기반 이미지 검색에서 개념적 이질성 극복을 위한 도메인 온톨로지 설계 및 구현)

  • Kim Won-Pil;Kim Pan-Koo
    • Journal of Internet Computing and Services
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    • v.4 no.4
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    • pp.1-8
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    • 2003
  • As the multimedia information retrieval system is advanced, the study of multimedia information retrieval is changing the method of low-level content based image retrieval to the semantical concept based retrieval. in this paper, we apply the theory of ontology to overcome the conceptual heterogeneity in the annotation based image retrieval. And we solve the some problems that happen when the ontology apply. As a result of our study, we try to apply the domain ontology to settle the conceptual heterogenity. In the experimental result, we knew that the semantic distance among the words is pretty dose when we apply the domain ontology than the wordnet. And in this paper, we show the possibility of the semantic image retrieval as we apply the domain ontology in the annotation based image retrieval.

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