• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.36 no.9B
• /
• pp.1039-1048
• /
• 2011

Carrier Ethernet, which extend The algorithm based on constructing the mixed topology and performing link stretching, MT/s, has been proposed for designing cost-efficient Carrier Ethernet in optical network with multi-line-rate. However, the MT/s algorithm has high blocking ratio because the wavelength capacity is fully allocated without considering the load balance of network. In this paper, we propose an efficient mixed topology configuration (EMTC) algorithm by modifying MT/s algorithm. In order to reduce blocking ratio, we adapt a threshold for each link to restrict the link utilization so that traffic load can be distributed over whole network. We also apply the EMTC algorithm into optical hybrid switched network to evaluate the availability of our algorithm for different applications. The performance of the EMTC algorithm is compared with that of MT/s algorithm through OPNET simulation. The simulation results show that our algorithm achieve lower blocking ratio than the MT/s algorithm. Moreover, in hybrid switched network, our algorithm performs better than MT/s algorithm in terms of packet loss ratio and end-to-end delay.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.1
• /
• pp.166-173
• /
• 2013

As the number of IPs and the communication volume among them have constantly increased, on-chip crossbar network is now the most widely-used on-chip communication backbone of contemporary SoCs. The on-chip crossbar network consists of multiple crossbars and the connections among the IPs and the crossbars. As the complexity of SoCs increases, it has also become more and more complex to determine the topology of the crossbar network. To tackle this problem, this paper proposes an on-chip crossbar network topology method for application-specific systems. The proposed method uses mixed integer linear programming to solve the topology synthesis problem, thus the global optimality is guaranteed. Unlike the previous MILP-based methods which represent the topology with adjacency matrixes of IPs and crossbar switches, the proposed method uses the communication edges among IPs as the basic element of the representation. The experimental results show that the proposed MILP formulation outperforms the previous one by improving the synthesis speed by 77.1 times on average, for 4 realistic benchmarks.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.12
• /
• pp.3843-3846
• /
• 2013

• Steel and Composite Structures
• /
• v.27 no.1
• /
• pp.27-33
• /
• 2018

In this study, a mixed-interpolated tensorial component 4 nodes method (MITC4) is treated as a numerical analysis model for topology optimization using multiple materials assigned within Reissner-Mindlin plates. Multi-material optimal topology and shape are produced as alternative plate retrofit designs to provide reasonable material assignments based on stress distributions. Element density distribution contours of mixing multiple material densities are linked to Solid Isotropic Material with Penalization (SIMP) as a design model. Mathematical formulation of multi-material topology optimization problem solving minimum compliance is an alternating active-phase algorithm with the Gauss-Seidel version as an optimization model of optimality criteria. Numerical examples illustrate the reliability and accuracy of the present design method for multi-material topology optimization with Reissner-Mindlin plates using MITC4 elements and steel materials.

• Steel and Composite Structures
• /
• v.35 no.1
• /
• pp.129-145
• /
• 2020

In typical, structural topology optimization plays a significant role to both increase stiffness and save mass of structures in the resulting design. This study contributes to a new numerical approach of topologically optimal design of Mindlin-Reissner plates considering Winkler foundation and mathematical formulations of multi-directional variable thickness of the plate by using multi-materials. While achieving optimal multi-material topologies of the plate with multi-directional variable thickness, the weight information of structures in terms of effective utilization of the material at the appropriate thickness location may be provided for engineers and designers of structures. Besides, numerical techniques of the well-established mixed interpolation of tensorial components 4 element (MITC4) is utilized to overcome a well-known shear locking problem occurring to thin plate models. The well-founded mathematical formulation of topology optimization problem with variable thickness Mindlin-Reissner plate structures by using multiple materials is derived in detail as one of main achievements of this article. Numerical examples verify that variable thickness Mindlin-Reissner plates on Winkler foundation have a significant effect on topologically optimal multi-material design results.

• Steel and Composite Structures
• /
• v.48 no.5
• /
• pp.583-597
• /
• 2023

This paper introduces a novel approach to multi-material topology optimization (MTO) targeting in-plane bi-directional functionally graded (IBFG) non-uniform thickness Reissner-Mindlin plates, employing an alternative active phase approach. The mathematical formulation integrates a first shear deformation theory (FSDT) to address compliance minimization as the objective function. Through an alternating active-phase algorithm in conjunction with the block Gauss-Seidel method, the study transforms a multi-phase topology optimization challenge with multi-volume fraction constraints into multiple binary phase sub-problems, each with a single volume fraction constraint. The investigation focuses on IBFG materials that incorporate adequate local bulk and shear moduli to enhance the precision of material interactions. Furthermore, the well-established mixed interpolation of tensorial components 4-node elements (MITC4) is harnessed to tackle shear-locking issues inherent in thin plate models. The study meticulously presents detailed mathematical formulations for IBFG plates in the MTO framework, underscored by numerous numerical examples demonstrating the method's efficiency and reliability.

• Proceedings of the Korean Institute of Interior Design Conference
• /
• 2005.10a
• /
• pp.183-186
• /
• 2005

The purpose of this study is to actualize the planning method of the Mixed-use Housing. Enter in 2000 years, contruction of Mixed-use Housing is rapidly increasing with acrovill and tower palace as its starting point. Mixed-use Housing is topology that mix function of residential and business and commercial facilities by kind of mixed-use development. And, Mixed-use Housing which is located in busy urban commercial strict should meet the demand not only as functional city. And it is a type of urban housing that located in busy urban commercial district demands function of residential. As for locational situation and types of public space researched and analyzed in this thesis, those space were left alone with short analyzation on main consumers level as well as short recognition of public space for all of the six combined facilities of dewelling and commercing

• Journal of the Optical Society of Korea
• /
• v.19 no.1
• /
• pp.13-21
• /
• 2015

In recent years energy consumption has become a main concern for network development, due to the exponential increase of network traffic. Potential energy savings can be obtained from a load-adaptive scheme, in which a day can be divided into multiple time periods according to the variation of daily traffic patterns. The energy consumption of the network can be reduced by selectively turning off network components during the time periods with light traffic. However, the time segmentation of daily traffic patterns affects the energy savings when designing multiperiod logical topology in optical wavelength routed networks. In addition, turning network components on or off may increase the overhead of logical topology reconfiguration (LTR). In this paper, we propose two mixed integer linear programming (MILP) models to design the optimal logical topology for multiple periods in IP-over-WDM networks. First, we formulate the time-segmentation problem as an MILP model to optimally determine the boundaries for each period, with the objective to minimize total network energy consumption. Second, another MILP formulation is proposed to minimize both the overall power consumption (PC) and the reconfiguration overhead (RO). The proposed models are evaluated and compared to conventional schemes, in view of PC and RO, through case studies.

• Proceedings of the KIEE Conference
• /
• 1999.07f
• /
• pp.2786-2788
• /
• 1999

In this paper, a mixed mode exciting resonant inverter topology applicable to high performance electronic ballast is presented. Mixed mode exciting technique combines the attractive features of self exciting resonant inverter with those of external exciting one. The control IC is designed and manufactured by using a 0.8um CMOS process for 5V operation and has only 8 pins. This performs the operations of filament preheating, dimming control, output power regulation and protections. The mixed mode exciting resonant inverter with control IC has very simple structure, high performance and expensive manufacturing cost.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.10a
• /
• pp.1051-1054
• /
• 2005

On this study, we optimized minimizing the characteristic function for mixed result of the structural contact analysis and the buckling analysis according to the pin jig initial model's level change using mixed the table of orthogonal away and ANOM, Pin jig's weight is reduced up to 20 percent considering constraint conditions. Also we optimized reducing 20 percent weight of pin jig model using topology optimization.