• Journal of Information Technology Applications and Management
• /
• v.19 no.1
• /
• pp.37-46
• /
• 2012

The scheduling problem of large products like ships, airplanes, space shuttles, assembled constructions, and automobiles is very complex in nature. To reduce inherent computational complexity, we often design scheduling systems that the original problem is decomposed into small sub-problems, which are scheduled independently and integrated into the original one. Moreover, the steep growth of communication technology and logistics makes it possible to produce a lot of multi-nation corporation by which products are produced across more than one plant. Therefore vertical and lateral coordination among decomposed scheduling systems is necessary. In this research, we suggest an agent-based coordinating mechanism for multi-level scheduling systems in supply chain. For design of a general coordination mechanism, at first, we propose a grammar to define individual scheduling agents which are responsible to their own plants, and a meta-level coordination agent which is engaged to supervise individual scheduling agents. Second, we suggest scheduling agent communication protocols for each scheduling agent topology which is classified according to the system architecture, existence of coordinator, and direction of coordination. We also suggest a scheduling agent communication language which consists of three layers : Agent Communication Layer, Scheduling Coordination Layer, Industry-specific Layer. Finally, in order to improve the efficiency of communication among scheduling agents we suggest a rough capacity coordination model which supports to monitor participating agents and analyze the status of them. With this coordination mechanism, we can easily model coordination processes of multiple scheduling systems. In the future, we will apply this mechanism to shipbuilding domain and develop a prototype system which consists of a dock-scheduling agent, four assembly-plant-scheduling agents, and a meta-level coordination agent. A series of experiment using the real-world data will be performed to examine this mechanism.

• Korean Journal of Plant Tissue Culture
• /
• v.24 no.2
• /
• pp.113-117
• /
• 1997

Simple sequence repeats (SSR) are widely dispersed throughout eukaryotic genomes, highly polymorphic, and easily typed using polymerase chain reaction (PCR). The objective of this study was to determine the polymorphism of different Chlamydomonas reinhartdtii strains and to determine the mode of inheritance of the SSR locus in Chlamydomonas. A genomic DNA library of C. reinhardtii was constructed and screened with a radiolabeled $(AC)_{11}$ probe for the selection of (CA/GT)n repeat clone. Selected clone was seqeuenced, and PCR primer set flanking (CA/GT)n sequence was constructed. PCR was used to specifically amplify the SSR locus from multiple isolates of C. reinhardtii. The locus was polymorphic in some of the C. reinhardtii isolates. However, the locus was amplified only 4 of 6 isolates of C. reinhardtii, not in other 2 isolates of C. reinhardtii, suggesting that this locus is not extensively conserved. A simple Mendelian inheritance pattern was found, which showed 2:2 segregation in the tetrads resulting from a cross between C. reinhardtii and C. smithii. Our results suggest that this simple sequence repeat DNA polymorphism will be useful for identity testing, population studies, linkage analysis, and genome mapping in Chlamydomonas.

• Journal of Institute of Control, Robotics and Systems
• /
• v.17 no.9
• /
• pp.932-940
• /
• 2011

This paper presents an integrated analysis of supply chain and financing decisions of multi-national corporation. We construct a model in which multiple currency storage units are installed to manage the currency flows associated with multi-national supply chain activities such as raw material procurement, process operation, inventory control, transportation and finished product sales. Core contribution of this study is to quantitatively investigate the influence of macroscopic economic factors such as exchange rates and taxes on operational decisions. The supply chain is modeled by the Process-Storage Network with recycle streams. The objective function of the optimization is minimizing the opportunity costs of annualized capital investments and currency/material inventories minus the benefit to stockholders interpreted by home currency. The major constraints of the optimization are that the material and currency storage units must not be depleted. A production and inventory analysis formulation, the periodic square wave (PSW) model, provides useful expressions for the upper/lower bounds and average levels of the currency and material inventory holdups. The expressions for the Kuhn-Tucker conditions of the optimization problem are reduced to a subproblem and analytical lot sizing equations. The procurement, production, transportation and financial transaction lot sizes can be determined by analytical expressions after the average flow rates are already known. We show that, when corporate income tax is taken into consideration, the optimal production lot and storage sizes are smaller than is the case when such factors are not considered typically by 20 %.

• Journal of Digital Convergence
• /
• v.12 no.6
• /
• pp.311-316
• /
• 2014

Social network server due to the popularity of smart phones, and data stored in a big usable access data services are increasing. Big Data Big Data processing technology is one of the most important technologies in the service, but a solution to this minor security state. In this paper, the data services provided by the big -sized data is distributed using a double hash user to easily access to data of multiple distributed hash chain based data processing technique is proposed. The proposed method is a kind of big data data, a function, characteristics of the hash chain tied to a high-throughput data are supported. Further, the token and the data node to an eavesdropper that occurs when the security vulnerability to the data attribute information to the connection information by utilizing hash chain of big data access control in a distributed processing.

• Journal of Distribution Science
• /
• v.15 no.9
• /
• pp.95-107
• /
• 2017

Purpose - In the joint development of new products, buyers and suppliers exchange information to solve various problems. Uncertainty and ambiguity are typical examples. Uncertainty refers to the lack of information to solve the problem, and equivocality refers to the case where the information is interpreted in multiple processes in the process of providing the information. These uncertainty and equivocality cause new products to be delayed in their development and adversely affect quality. However, unfortunately, there is a lack of researches on how the uncertainty and equivocality of such concepts control the results of new product joint development. But, smooth communication and effective exchange of information is not emphasized only in the general organization. The importance of the new product joint development projects to achieve the two organizations' common goals becomes even greater. The purposes of this study are to analyse the effect of supplier's strategy on the NPD performance and moderating effect of uncertainty and equivocality. Research design, data, and methodology - In order to make a contribution to the lack of academic researches in Korea, this study collects data through questionnaires based on organizational information processing theory and previous studies, and conducts empirical analysis. Results - As a result, the product modularization strategy and the strategic supply chain relationship positively influenced the new product development performance - return on investment and ease of manufacturing. And the interaction effect of uncertainty and equivocality with supplier's strategy - product modularity strategy and strategic supply chain management relationship - reduces or negates the influence of product modularization strategy on new product development performance. Conclusions - This implies that it is important to control uncertainty and equivocality in order for the supplier strategy to have a positive effect on new product development performance. It also emphasizes the necessity of sharing information appropriately for companies that do not want to share the information as possible due to their fear of loss of competitive advantage in the joint development of new products. Because this kind of negative policy might let uncertainty and equivocality be happen in new product joint development process.

• The Journal of Internal Korean Medicine
• /
• v.25 no.4
• /
• pp.9-17
• /
• 2004

Objective : Mesangial cell proliferation and excessive accumulation of extracellular matrix (ECM) proteins is the common pathologic feature of glomerulosclerosis, and platelet-derived growth factor (PDGF) BB-chain, transforming growth factor betal $(TGF-{\beta}1)$, cyclin dependent kinases (CDK) and CDK inhibitors mediated in these pathophysiological processes. Bupleurum falcatum which is one of the most widely used components in traditional oriental medicines, has multiple pharmacological effects, such as antipyretic, analgesic, immune modulating, anti-inflammatory, anti-allergic, anti-thrombotic, anti-atherosclerotic, and antitussive effects. Methods : In this study, we evaluated the influence of Bupleurum falcatum on mesangial cell proliferation, DNA synthesis and expression of PDGF-BB chain, $TGF-{\beta}1$, CDKI, CDK2, CDK4, p21 and p27 in fetal bovine serum (FBS)-activated human mesangial cell. Results : Bupleurum falcatum reduced the mesangial cell proliferation and DNA synthesis more than control and captopril. And in the ELISA analysis of $TGF-{\beta}1$, and RT-PCR of PDGF-BB chain, CDK1, CDK2, CDK4, p21, and p27, Bupleurum falcatum inhibited the expression of $TGF-{\beta}1$ protein and PDGF-BB, CDK1, CDK2 gene and promoted that of p21 gene in a dose-dependent manner in comparing with control and captopril. Conclusions: These results suggest that Bupleurum falcatum may inhibit the mesangial cell proliferation and DNA synthesis by regulation of PDGF-BB and $TGF-{\beta}1$ expressions, and by modulation of CDK1, CDK2 and p21 expression.

• Journal of Digital Convergence
• /
• v.13 no.1
• /
• pp.263-268
• /
• 2015

Put your information in the object-based sensors and mobile networks has been developed that correlate with ubiquitous information technology as the development of IT technology. However, a security solution is to have the data stored in the server, what minimal conditions. In this paper, we propose a data management method is applied to a hash chain of the properties of the multiple techniques to the data used by the big user and the data services to ensure safe handling large amounts of data being provided in the big data services. Improves the safety of the data tied to the hash chain for the classification to classify the attributes of the data attribute information according to the type of data used for the big data services, functions and characteristics of the proposed method. Also, the distributed processing of big data by utilizing the access control information of the hash chain to connect the data attribute information to a geographically dispersed data easily accessible techniques are proposed.

• Journal of Communications and Networks
• /
• v.15 no.1
• /
• pp.77-86
• /
• 2013

Cognitive radio (CR) has emerged as one of effective methods to enhance the utilization of existing radio spectrum. Main principle of CR is that secondary users (SUs) are allowed to use the spectrum unused by primary users (PUs) without interfering PU's transmissions. In this paper, PUs operate on a slot-by-slot basis and SUs try to exploit the slots unused by PUs. We propose OSA protocols in the single channel and we propose an opportunistic spectrum access (OSA) protocols in the multi-channel cognitive radio networks with one control channel and several licensed channels where a slot is divided into contention phase and transmission phase. A slot is divided into reporting phase, contention phase and transmission phase. The reporting phase plays a role of finding idle channels unused by PUs and the contention phase plays a role of selecting a SU who will send packets in the data transmission phase. One SU is selected by carrier sense multiple access / collision avoidance (CSMA/CA) with request to send / clear to send (RTS/CTS) mechanism on control channel and the SU is allowed to occupy all remaining part of all idle channels during the current slot. For mathematical analysis, first we deal with the single-channel case and we model the proposed OSA media access control (MAC) protocol by three-dimensional discrete time Markov chain (DTMC) whose one-step transition probability matrix has a special structure so as to apply the censored Markov chain method to obtain the steady state distribution.We obtain the throughput and the distribution of access delay. Next we deal with the multi-channel case and obtain the throughput and the distribution of access delay by using results of single-channel case. In numerical results, our mathematical analysis is verified by simulations and we give numerical results on throughput and access delay of the proposed MAC protocol. Finally, we find the maximum allowable number of SUs satisfying the requirements on throughput and access delay.

• Journal of Ocean Engineering and Technology
• /
• v.32 no.5
• /
• pp.297-309
• /
• 2018

After an accident involving mooring link failures in an offloading buoy, verification of the fatigue safety in terms of the out-of-plane bending (OPB) and in-plane bending (IPB) moments has become a key engineering item in the design of various floating offshore units. The mooring links for an 8 MW floating offshore wind turbine were selected for this study. To identify the OPB stiffness (OPB moment versus interlink angle), a numerical simulation model, called the 3-link model, is usually composed of three successive chain links closest to the fairlead or chain hawse. This paper introduces two numerical simulation techniques for the 3-link analyses. The conventional and advanced approaches are both based on the prescribed rotation approach (PRA) and direct tension approach (DTA). Comparisons of the nominal stress distributions, OPB stiffnesses, hotspot stress curves, and stress concentration curves are presented. The multiple link analyses used to identify the tension angle versus interlink angle require the OPB stiffness data from the 3-link analyses. A convergence study was conducted to determine the minimum number of links for a multi-link analysis. It was proven that 10 links were sufficient for the multi-link analysis. The tension angle versus interlink angle relations are presented based on multi-link analyses with 10 links. It was found that the subsequent results varied significantly according to the 3-link analysis techniques.

• Journal of Korean Society of Transportation
• /
• v.26 no.4
• /
• pp.87-97
• /
• 2008

The traditional trip-based modeling approach has assumed that a trip is generated for a purpose. However, the approach has not considered trips as a set of connected trips nor has it considered trip chaining. The purpose of this study is to identify general characteristics of trip chaining, and to explore relationships between trip purposes and trip chains using multivariate regression models. The data for this study come from the 2006 Seoul household travel diary survey. It is found that simple trip chains are dominant phenomena, and socio-economic characteristics such as occupation, income, age, and gender are closely related to types of trip chains. People aged less than 20, females, or high-income people are more likely to have a higher number of home-based trip chains. In addition, commute and school trips for workers and students respectively tend to be strongly associated with simple trip chains, while shopping and leisure trips for housewives tend to be related to simple trip chains.