• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제6권7호
• /
• pp.1735-1755
• /
• 2012

Wireless sensor networks (WSNs) are becoming increasingly attractive for a variety of applications and have become a hot research area. Routing is a key technology in WSNs and can be coarsely divided into two categories: flat routing and hierarchical routing. In a flat topology, all nodes perform the same task and have the same functionality in the network. In contrast, nodes in a hierarchical topology perform different tasks in WSNs and are typically organized into lots of clusters according to specific requirements or metrics. Owing to a variety of advantages, clustering routing protocols are becoming an active branch of routing technology in WSNs. In this paper, we present an overview on clustering routing algorithms for WSNs with focus on differentiating them according to diverse cluster shapes. We outline the main advantages of clustering and discuss the classification of clustering routing protocols in WSNs. In particular, we systematically analyze the typical clustering routing protocols in WSNs and compare the different approaches based on various metrics. Finally, we conclude the paper with some open questions.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제14권4호
• /
• pp.1579-1602
• /
• 2020

In the design of production system, buffer capacity allocation is a major step. Through polymorphism analysis of production capacity and production capability, this paper investigates a buffer allocation optimization problem aiming at the multi-stage production line including unreliable machines, which is concerned with maximizing the system theoretical production rate and minimizing the system state entropy for a certain amount of buffers simultaneously. Stochastic process analysis is employed to establish Markov models for repairable modular machines. Considering the complex structure, an improved vector UGF (Universal Generating Function) technique and composition operators are introduced to construct the system model. Then the measures to assess the system's multi-state reliability and structural complexity are given. Based on system theoretical production rate and system state entropy, mathematical model for buffer capacity optimization is built and optimized by a specific genetic algorithm. The feasibility and effectiveness of the proposed method is verified by an application of an engine head production line.

• 산업공학
• /
• 제13권3호
• /
• pp.296-305
• /
• 2000

In supply chains, coordination between a manufacturer and suppliers is regarded as the most important issue when partnership of organizations is considered. Since the suppliers are external to the manufacturer and poor coordination between them results in excessive delays and ultimately leads to poor customer service, manufacturers need a new methodology to select suppliers and to manage and enhance the partnership between manufacturer and suppliers. We suggest a methodology that extends knowledge obtained from the supplier selection process to the supplier management process. We reserved a word, the supplier selection and management system (SSMS) for this methodology. In this paper, we explain how the SSMS is applied to a real supply chain. The methodology identifies the managerial criteria using information derived from supplier selection process and makes use of them in the supplier management process. These managerial criteria include key criteria that are major criteria required by the manufacturer for the best quality of parts from suppliers according to the character of each part, and weak criteria that show the shortcomings of selected suppliers as compared with alternative suppliers with regard to each criterion. The effectiveness of supplier management with managerial criteria was verified by a t-test and a correlation analysis with data collected and hypothesized from a Korean air-conditioner manufacturer.

• Journal of information and communication convergence engineering
• /
• 제3권3호
• /
• pp.157-162
• /
• 2005

Web services are key applications in business­to-business, business-to-customer, and enterprise applications integration solutions. As the mobile internet becomes one of the main methods for information delivery, mobile Web Services are regarded as a critical aspect of e-business architecture. In this paper, we proposed a mobile Web Services middleware that converts conventional internet services into mobile Web services. We implemented a WSDL (Web Service Description Language) builder that converts HTML/XML into WSDL and a SAOP (Simple Object Access Protocol) message processor that performs SOAP message handling, chain and handling of server requests. The former minimizes the overhead cost of rebuilding mobile Web Services and enables seamless services between wired and wireless internet services. The latter enhances SOAP processing performance by eliminating the Servlet container (Tomcat), a required component of typical Web services implementation. Our main contributions are to overcome the latency problem of current Web Services and to provide an easy mobile Web service implementation. Our system can completely support standard Web Services protocol, minimizing communication overhead, message processing time, and server overload. Finally we compare our empirical results with those of typical Web Services.

• Asian-Australasian Journal of Animal Sciences
• /
• 제30권1호
• /
• pp.111-118
• /
• 2017

Objective: Adipose tissue plays a key role in the development of obesity and diabetes. We previously reported that lignosulfonic acid suppresses the rise in blood glucose levels through the inhibition of ${\alpha}$-glucosidase activity and intestinal glucose absorption. The purpose of this study is to examine further biological activities of lignosulfonic acid. Methods: In this study, we examined the effect of lignosulfonic acid on differentiation of 3T3-L1 cells. Results: While lignosulfonic acid inhibited proliferation (mitotic clonal expansion) after induction of differentiation, lignosulfonic acid significantly increased the size of accumulated lipid droplets in the cells. Semi-quantitative reverse transcription polymerase chain reaction analysis showed that lignosulfonic acid increased the expression of the adipogenic transcription factor, peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$), leading to increased glucose transporter 4 (Glut-4) expression and 2-deoxyglucose uptake in differentiated 3T3-L1 cells. Additionally, feeding lignosulfonic acid to diabetic KK-Ay mice suppressed increase of blood glucose level. Conclusion: Lignosulfonic acid may be useful as a functional anti-diabetic component of food.

• Journal of Nutrition and Health
• /
• 제30권9호
• /
• pp.1067-1072
• /
• 1997

One known effect of long chain n-3 polyunsaturated fatty acids is their ability to decrease plasma triglycerides. However, identification of the specific n-3 fatty acids and the underlying mechanisms responsible for this change remains uncertain. This present study was designed to evaluate the effects of moderate levels of dietary docosahexaenoic acid (22 :6(n-3)) on modulating plasma triglyderides. Male CD-1 mice were maintained for 15 days on identical diets containing either docosahexahexaenoic acid ethyl ester(1.5%, w/w) or linoleic acid(18 : 2(n-6)) ethyl ester (1.5%, w/w) . Plasma triglycerides were 40% lower in the docosahexaenoic acid group than in the linoleic acid group. Hepatic carnitine palmitoyltransferase activity (a key regulatory enzyme for mitocondria $\beta$-oxidation) was not significantly different between the dietary groups. However, plasma acid soluble acylcarnitine levels (which increase with increasing $\beta$-oxidation )were significantly higher in the decosahexaenoic acid group. This data suggests that plasma triglyceride levels are lower in mice fed diets containing moderate levels of docosahexaenoic acid compared to linoleic acid, but this effect on plasma triglycerides is not modulated through an augmentation of mitochondrial $\beta$-oxidation.

• 산경연구논집
• /
• 제9권5호
• /
• pp.7-15
• /
• 2018

Purpose - The development of Anhui high-tech industry is the key to transforming the mode of economic development and optimizing the industrial structure. Research design, data, and methodology - The data of paper that is the data of Anhui province and the six provinces of central China from 2010 to 2015, which analyzed the present situation of High-tech industry in Anhui Province by means of data comparison and literature analysis, and then explored several possible modes of undertaking. Results - With the analysis of the current situation of the development of high-tech industry in Anhui Province, several possible modes for undertaking the transfer of high-tech industries in Anhui Province were explored: The mode of undertaking of Leading Enterprises + Industrial park, the mode of undertaking of differentiated development + Regional comprehensive exploitation and the mode of undertaking "Dynamic industrial Chain" + industrial cluster. Conclusions - Based on the perspective of industrial upgrading, this paper analyzes the shortcomings of Anhui Province in the traditional mode of undertaking industrial transfer and expounds the inherent requirements of innovation industry undertaking. Finally, on the basis of the above analysis, the author explored three possible modes of acceptance.

• 시스템엔지니어링학술지
• /
• 제9권2호
• /
• pp.37-53
• /
• 2013

With rapid growth of the world plant market, an increasing attention is paid on the plant engineering. Up to present time, Korean plant engineering technology has been concerned with the down stream part of the plant engineering, so called EPC, considered as a lower value chain compared with the up stream, composed of FEED(Front End Engineering Design) and PMC(Project Management Consultancy). In other words, a key issue for Korean plant industry is how to catch up the FEED technology, currently occupied by the advanced countries. In this paper, we propose an SE(Systems Engineering) approach, conventionally applied for aerospace and defense industry, to the FEED for plant engineering. Specifically, we proposed a new SE process composed of: 1) SPA matrix for reverse systems engineering, and 2) PPA matrix for forward systems engineering. To illustrate the proposed method, a case study for an environmental plant is performed.

• 한국디지털정책학회:학술대회논문집
• /
• 한국디지털정책학회 2006년도 춘계학술대회
• /
• pp.45-53
• /
• 2006

Ever since the computer came into being in early 20th century, rapid development of the information technology has led to the opening of the ubiquitous age where daily works can be done anywhere, anytime, and with any devices. The information technology has drawn attention from Customs around the world as a key means to fulfill multi-faced responsibilities of strengthening regional cooperation in the international trade, simplifying clearance procedures, expediting logistics flow, and ensuring security in the global supply chain. Korea Customs Service, which began the informatization effort by establishing the electronic export declaration system in 1992, completed the 100% electronic clearance system in 2000, with a number of countries now conducting benchmarking studies on the successful use of IT by KCS. This paper is to address the changes brought to the Customs administration in the information age, the progress and achievement of the Customs informatization as a proactive strategy to deal with the changing environment, and the exportation to overseas administration of the e-clearance system of KCS which strives to become the global leader of Customs informatization. The exportation. in particular, will not only lead to increased foreign currency earnings and shared know how, but also create an opportunity to reflect Korea's system in the standardization of Customs procedures around the world.

• Preventive Nutrition and Food Science
• /
• 제22권1호
• /
• pp.50-55
• /
• 2017

Raphanus sativus L. (RS) is a cruciferous vegetable that is widely consumed in Korea. The anticancer activity of leaves of RS (RSL) extract has been investigated; however, no studies focused on its anti-inflammatory effects. Therefore, the aim of the current study was to evaluate the anti-inflammatory effects of RSL extract. In brief, RSL powder was fractionated into n-hexane, chloroform, ethyl acetate, n-butanol, and water-soluble fractions. Lipopolysaccharide (LPS)-stimulated RAW264.7 cells were treated with each fraction for initial screening. It was found that the chloroform fraction significantly inhibited nitric oxide release in LPS-stimulated RAW264.7 cells with a half maximal inhibitory concentration value of $196{\mu}g/mL$. In addition, the mRNA and protein expression levels of inducible nitric oxide synthase, measured using reverse transcriptase-polymerase chain reaction and western blotting, respectively, were reduced in a concentration-dependent manner. Moreover, the inflammatory cyclooxygenase-2 enzyme expression decreased. Furthermore, the expression of nuclear factor-kappa B ($NF-{\kappa}B$), the key regulator of the transcriptional activation of the inflammatory cytokine genes, was reduced by the RSL chloroform fraction. Therefore, the results of our study suggest that RSL exhibits anti-inflammatory effects in LPS-stimulated macrophages via $NF-{\kappa}B$ inactivation.