• Management Science and Financial Engineering
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• v.6 no.2
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• pp.29-45
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• 2000

We consider the design of a two-level telecommunication network having logical full-mesh/star topology, with the implementation of conduit systems taken together. The design problem is then viewed as consisting of three subproblems: locating hub facilities, placing a conduit network, and installing cables therein to configure the logical full-mesh/star network. Without partitioning into subproblems as done in the conventional approach, the whole problem is directly dealt with in a single integrated framework, inspired by some recent successes with the approach. We successfully formulate the problem as a variant of the classical multicommodity flow model for the fixed charge network design problem, aided by network augmentation, judicious commodity definition, and some flow restrictions. With our optimal model, we solve some randomly generated sample problems by using CPLEX MIP program. From the computational experiments, it seems that our model can be applied to the practical problem effectively.

• Korean Management Science Review
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• v.14 no.1
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• pp.87-105
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• 1997

There have been lots of research on temporal data management for the past two decades. Most of them are based on some logical data model, especially on the relational data model, although there are some conceptual data models which are independent of logical data models. Also, many properties or issues regarding temporal data models and temporal query languages have been studied. But some of them were shown to be incompatible, which means there could not be a complete temporal data model, satisfying all the desired properties at the same time. Many modeling issues discussed in the papers, do not have to be done so, if they take object-oriented data model as a base model. Therefore, this paper proposes a temporal data model, which is based on the object-oriented data model, mainly discussing the most essential issues that are common to many temporal data models. Our new temporal data model and query language will be illustrated with a small database, created by a set of sample transaction.

• Journal of KIISE:Databases
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• v.30 no.3
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• pp.237-251
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• 2003

In this paper, we propose a video retrieval system to search logical structure and semantic contents of video data efficiently. The proposed system employs a layered modelling method that orBanifes video data in raw data layer, content layer and key frame layer. The layered modelling of the proposed system represents logical structures and semantic contents of video data in content layer. Also, the proposed system supports various types of searches such as text search, visual feature based similarity search, spatio-temporal relationship based similarity search and semantic contents search.

• Journal of the Korean Society for information Management
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• v.18 no.3
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• pp.219-238
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• 2001

This paper is proposed next generation digital library models which based on the understanding of changes in digital library and business paradigm. The models which were proposed at the paper are applied electronic commerce technologies to digital libraries. The logical model was developed in the area of library material acquisition to participate various related agents during acquisition processes into single eMarketplace. The paper was developed detailed eMarketplace logical model to integrate and transact library material acquisition process.

• The Korean Journal of Applied Statistics
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• v.18 no.2
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• pp.445-452
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• 2005

We considered the frequency and classical probabilities under cuboctahedral die with 8 hexagons and 6 regular squares and compared with the frequency and logical probabilities under cuboctahedral die with 8 triangles and 6 regular squares.

• Journal of the Korea Society for Simulation
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• v.4 no.2
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• pp.31-40
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• 1995

A hybrid simulation model consists of real physical entities as well as simulated ones. It also contains logical processes for decision making for each operation units, a group of the entities. During the execution of such simulations, the physical and the logical processes consume real clock time while the activity durations of the simulated ones are generated. Due to the inherent chracteristics of the subjects of the communication channels. Since one can not undo an real event already taken place, the traditional central clock approach is used for the synchronization of the events(Kim[6]). However, there are still chances of causality errors due to the randomness in the communication delays. This error is not found in the distributed pure simulations. This paper explains the error in details and proposes a prevention scheme that is simple to implement.

• Journal of the Korean Operations Research and Management Science Society
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• v.14 no.1
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• pp.87-87
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• 1989

There have been lots of research on temporal data management for the past two decades. Most of them are based on some logical data model, especially on the relational data model, although there are some conceptual data models which are independent of logical data models. Also, many properties or issues regarding temporal data models and temporal query languages have been studied. But some of them were shown to be incompatible, which means there could not be a complete temporal data model, satisfying all the desired properties at the same time. Many modeling issues discussed in the papers, do not have to be done so, if they take object-oriented data model as a base model. Therefore, this paper proposes a temporal data model, which is based on the object-oriented data model, mainly discussing the most essential issues that are common to many temporal data models. Our new temporal data model and query language will be illustrated with a small database, created by a set of sample transaction.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.28B no.7
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• pp.520-534
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• 1991

This paper describes the design of an ALU and a shifter for RISC. The RISC datapath is designed to have a 4-stage pipeline and a 20 MHz operating frequency. The ALU makes use of the 32-bit BLC adder which has the characteristics of high speed ane regular structuer and executes the arithmetic instructions-addition and subtraction- and the logical instructions-AND, OR, and XOR. Additionally, multiplication is possible by iterative executions of step instructions to perform shift and add operations. The shifter is implemented by using the modified of funnel shifter. The shifter is able to perform the arithmetic andlogical shift instructions without maskiog. Moreover, it carries out data align operation which conforms to big endian byte address. The logical operation of the desinged ALU and the shifter were simulated using YSLOG and VLSIsim. SPICE simulation results using 1.2um double metal process parameters show that the ALU and shifter have a delay time of 15.9NS and 9.9NS, respectively. Therefore, the ALU and the shifter operates correctly above 20[ MHz ] click ferquency and are composed of about 7K and 15K teansistors, respectively.

• Korean Journal of Logic
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• v.9 no.2
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• pp.99-116
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• 2006

There has been several proposals to resolve the gentle murder paradox; Forrester claims that the paradox shows that the deontic closure principle should be abandoned, while Sinnott-Armstrong claims that the paradoxical result arises from the scope ambiguity. However, I shall argue, the gentle murder paradox hinges on the logical structure of adverbial expressions. Although Davidson shows an insightful way of understanding logical structure of adverbs, there has been misunderstandings concerning the nature of his account. Especially what is called neo-Davidsonian event semantics is based upon combination of two fundamentally conflicting ideas. I shall propose a new way of understanding Davidson's account, on the basis of which I continue to give a new diagnosis of the gentle murder paradox.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.6B
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• pp.523-532
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• 2003

GENMET(GEneralized Multihop Network) which is based on Wavelength-Division Multiplexsing(WDM) and can be used in order to construct the next generation lightwave network is a logical(virtual), packet-switched and multihop topology network. GENMET is a regular multihop network which is a generalization of Shuffle network and do Bruijn network As such, it has the advantage of simple routing which is critical in a high speed network Given a physical topology, different logical topologies can be derived for assigning wavelengths to the UserNodes. By appropriately assigning wavelengths, performance of the network, such as mean hop count, maximum throughput and mean packet delay can be improved. In this paper, we propose heuristic algorithms for effectively assigning a limited number of wavelengths to the given UserNodes. The Performance of proposed algorithm is compared with the random assignment and the lower bounds.