• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.579-584
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• 2004

In this paper, we present the mechanical, electrical system design and system integration of controllers including sensory devices of the humanoid, KHR-2 (KAIST Humanoid Robot - 2). We have developed KHR-2 since 2003. Total number of DOF of KHR-2 is 41. Each arm including a hand has 11 DOF and each leg has 6 DOF. Head and trunk also has 6 DOF and 1 DOF respectively. In head, two CCD cameras are used for eye. To control all axes efficiently, distributed control architecture is used to reduce computation burden of main controller and to expand devices easily. So we developed the sub-controller as a servo motor controller and a sensor interfacing devices using microprocessor. The main controller attached its back communicates with sub-controllers in real-time by CAN (Controller Area Network) protocol. We used Windows XP as its OS (Operation System) for fast development of main control program and easy extension of peripheral devices. And RTX HAL extension commercial software is used to realize the real-time control in Windows XP environment.

• Journal of Communications and Networks
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• 제11권1호
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• pp.20-25
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• 2009

The maximum likelihood detection with QR decomposition and M-algorithm (QRM-MLD) has been presented as a suboptimum multiple-input multiple-output (MIMO) detection scheme which can provide almost the same performance as the optimum maximum likelihood (ML) MIMO detection scheme but with the reduced complexity. However, due to the lack of parallelism and the regularity in the decoding structure, the conventional QRM-MLD which uses the tree-structure still has very high complexity for the very large scale integration (VLSI) implementation. In this paper, we modify the tree-structure of conventional QRM-MLD into trellis-structure in order to obtain high operational parallelism and regularity and then apply the Viterbi algorithm to the QRM-MLD to ease the burden of the VLSI implementation.We show from our selected numerical examples that, by using the QRM-MLD with our proposed trellis-structure, we can reduce the complexity significantly compared to the tree-structure based QRM-MLD while the performance degradation of our proposed scheme is negligible.

• 상하수도학회지
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• 제31권6호
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• pp.511-519
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• 2017

Multi-regional water supply system, which installed for supplying multiple water demands, is characterized by large-sized, long-distance, tree-type layout. This system is vulnerable to long-standing service interruption when a pipe breaks is occurred. In this study, a numerical method is proposed to calculate drainage time that directly affects time of service interruption. To begin with, governing equations are formulated to embed the delayed drainage effect by the friction loss, and to resolve complicated connection of pipelines, which are derived from the continuity and energy equations. The nonlinear hydraulic equations are solved by using explicit time integration method and the Newton-Raphson method. The developed model is verified by comparing the result with analytical solution. Furthermore, the model's applicability is validated by the examples of pipelines in serial, in parallel, and complex layout. Finally, the model is utilized to suggest an appropriate actions to reduce the deviation of draining time in the C transmission line of the B multi-regional water supply system.

• Journal of information and communication convergence engineering
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• 제8권5호
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• pp.473-478
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• 2010

Today's engineering design is carried out in a distributed fashion geographically or physically. This places new requirements on the computational environments such as efficient integration and collaboration. With the advances of the Internet and Network environment recently, many researches have been proposed and at the same time, Web-based distributed design gives to a new paradigm in design and manufacturing fields. That is, Web-based technologies lead to reduce the product development times and to ensure a competitive product in order to exchange and interact of real-time design information that integrates the distributed design environment between departments as well as companies via Internet and Web. So, an efficient data communication for design information sharing is the foundation for collaborative systems in the distributed environment. Design data communication techniques such as CORBA, DCOM and RMI have been considered in the existing research but they have some problems that are limitations of interoperability and firewall problems in the Web. Therefore, this paper presents a Web-based distributed design application where distributed design information resources are integrated and exchanged using Web Services for supporting XML and HTTP without the interoperability and firewall problems through the 330K VLCC case.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권7호
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• pp.3393-3412
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• 2017

As a main challenge in network virtualization, virtual network embedding problem is increasingly important and heuristic algorithms are of great interest. Aiming at the problems of poor correlation in node embedding and link embedding, long distance between adjacent virtual nodes and imbalance resource consumption of network components during embedding, we herein propose a two-stage virtual network embedding algorithm NA-PVNM. In node embedding stage, resource requirement and breadth first search algorithm are introduced to sort virtual nodes, and a node fitness function is developed to find the best substrate node. In link embedding stage, a path fitness function is developed to find the best path in which available bandwidth, CPU and path length are considered. Simulation results showed that the proposed algorithm could shorten link embedding distance, increase the acceptance ratio and revenue to cost ratio compared to previously reported algorithms. We also analyzed the impact of position constraint and substrate network attribute on algorithm performance, as well as the utilization of the substrate network resources during embedding via simulation. The results showed that, under the constraint of substrate resource distribution and virtual network requests, the critical factor of improving success ratio is to reduce resource consumption during embedding.

• 한국디지털건축인테리어학회논문집
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• 제10권3호
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• pp.79-86
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• 2010

From the research which sees the building which uses a natural control method with ecological architecture, continuity tried to divide the building which uses a physical control method with sustainable architecture. Ecological architecture analyzes the microclimate of the area and applies mining and natural ventilation leads and that the interior environment controls, the condition of the site actively and there is a possibility of seeing. Also sustainable architecture which is possible to lead and recycling and reuse of the resources and energy cyclic process of the construction resources to lead and the interior environment to control. Therefore the case where the facility system and structural system become integrated design organically in natural circulating method is many. Specially the sunshade system and double skin system are combined and structural system of the building and there is a possibility of having the envelope which form is feature. Today the buildings lead and the system integration process where the integral parts are systematic is demanded the interior environment which and an external form and that, they make they are there is a possibility of seeing. the environmental building which hits joins in with natural control method and the structure and facility system are integrated and has the tendency which is developed and there is a possibility of saying that a meaning with the alternative construction will be able to reduce the resources and an energy.

• 한국자동차공학회논문집
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• 제25권2호
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• pp.242-249
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• 2017

In this study, the relationship between the shape of a passenger airbag and the possibility of injury is analyzed using the Taguchi method. The optimal shape combination is proposed for a design guideline that can reduce the possibility of injury to the dummy. The airbag FE model for analysis is obtained using a CAD system that can change the shape through several independent variables. The widths of the left / right, top / bottom, and back / forth direction of the airbag shape are set as the design factors, and the effect of the combination injury probability according to the shape is analyzed. The minimum geometric combinations are obtained using the orthogonal array method. The signal to noise ratio is calculated and the optimal shape combination is obtained through sensitivity analysis. The obtained optimal shape combination is compared with the possibility of injury of the initial airbag shape to confirm improved airbag performance.

• Journal of Power Electronics
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• 제16권3호
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• pp.1190-1199
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• 2016

This study proposes a classification and compensation algorithm of two non-ideal output signals of a resolver to reduce position errors. Practically, a resolver generates position errors because of amplitude imbalance and quadrature imperfection between the two output signals of the resolver. In this study, a digital signal processor system based on a resolver-to-digital converter is used to reconstruct the two output signals of the resolver. The two output signals, "sin" and "cos," can be represented by a unit circle on the xy-plot. The classification and compensation of the errors can be obtained by using the radius and area of the circle made by the resolver signals. The method computes the integration of the areas made by the two resolver output signals to classify and compensate the error. This system cannot be applied during transient response given that the area integration during the transient state causes an error in the proposed method. The proposed method does not need any additional hardware. The experimental results verify the effectiveness of the proposed algorithm.

• 한국정보처리학회논문지
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• 제7권3호
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• pp.831-841
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• 2000

For the operation of the practical software systems, the development, extension and modification phases are successively needed through the new requirements added and their errors debugging detected. Therefore, if it is possible to integrated the reusable software components and to reorganize them into the new software systems, we can improve the productivity, quality, and cost-effectiveness for he development of software systems. For these reasons, it will be required to research and develop methodology and tools for programs integration which make some programs merged effectively. In the process of merging two versions of a program into one, we can consider that some parts of the two versions are equivalent under the non-interference between them. According to the previous studies the program selected to determine the criterion of non-interference between them. According to the previous studies the program selected to determine the criterion of non-interference was very large, so we have difficulty in integrating many programs practically. In this paper, we propose a new improved algorithm which can reduce the related program size of non-interference criterion yb use of dynamic slicing techniques for integration of two versions of a program, and prove the efficiency of the proposed algorithm by showing some examples.

• 정보학연구
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• 제1권1호
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• pp.1-11
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• 1998

시장에서의 치열한 경쟁으로 오늘날의 기업들은 고객에게 더 나은 제품과 서비스를 제공하면서도 동시에 가격 경쟁우위를 잃지 말아야만 하는 상충되는 과제를 안고 있다. 그러한 관점에서 효과적인 물류관리는 기업에 있어 매우 유용한 경쟁우위의 원천이 될 수 있을 것이다. 이를 위해 많은 기업들은 통합적인 공급체인관리(supply chain management)를 통해 공급체인내의 모든 기업들이 공생하고자 하는 목표를 추구하고 있다. 그러나 상이한 운영시스템과 조직특성을 가진 기업간의 연계로 공급체인내에 비효율성이 발생할 가능성이 매우 높다. 정보시스템의 활용은 그러한 비효율성을 제거하고 더 나아가 경쟁우위를 확보하는 수단으로 부각되고 있다. 본 연구에서는 특히 공급체인내에서 정보의 통합화가 물류성과에 미치는 영향을 분석함으로서 공급체인관리에서 정보시스템의 역할을 재고하고자 한다.