• The KIPS Transactions:PartD
• /
• v.11D no.4
• /
• pp.809-822
• /
• 2004

In this paper, we propose a concurrency control algorithm based on R-tree for spatial database management system. The previous proposed algorithms can't prevent problem that search operation is to be blocking during update operations. In case of multidimensional indexes like R-tree, locking of update operations may be locked to several nodes, and splitting of nodes have to lock a splitting node for a long time. Therefore search operations have to waiting a long time until update operations unlock. In this paper we propose new algorithms for lock-free search operation. First, we develop a new technique using a linked-list technique on the node. The linked-list enable lock-free search when search operations search a node. Next, we propose a new technique using a version technique. The version technique enable lock-free search on the node that update operations is to be splitting.

• The Korean Journal of Food And Nutrition
• /
• v.24 no.3
• /
• pp.414-421
• /
• 2011

시중에 유통 중인 영양보충용 제품의 수용성 비타민 $B_1$(thiamin), $B_2$(riboflavin), $B_3$(nicotinic acid and nicotine amide), $B_6$(pyridoxine), C(ascorbic acid)의 신속한 동시분석 방법을 확립하기 위하여 본 연구를 실시하였다. 영양보충용 제품은 정제, 연질캅셀, 분말, 액상의 4가지 제형에 대해 27종의 제품을 구입한 후, Ion-pair 분리기법을 사용하여 HPLC-UVD를 이용한 동시분석 방법을 검토하였다. 비타민 $B_1$, $B_2$, $B_3$, $B_6$, C의 HPLC에 의한 동시분석 조건을 검토한 결과, 이동상은 0.02% triethylamine, 17.5% 메탄올, $5{\mu}M$ sodium hexanesulfonic acid가 함유된 pH 3.5(acetic acid로 조절)의 수용액을 사용하였고, 용출시간은 다른 피크의 영향을 받지 않도록 30분으로 하였다. 수용성 비타민의 회수율은 96% 이상이었다. 본 연구에 의해 확립된 수용성 비타민의 동시분석 조건은 검량선의 직선성, 정밀성, 정확성, 기기적합성 등이 USP 및 ICH 기준에 적합하여 HPLC의 동시분석 방법으로 합당하였다. 수용성 비타민의 추출 용매는 제형에 따라 약간의 차이를 보이긴 했으나, 물이나 산성조건을 갖춘 HPLC의 이동상이 에탄올이나 메탄올보다 높은 추출 효율을 보였다. 초음파 추출기에 의한 추출 시간은 20분이 가장 적당하였다. 본 연구의 결과는 수용성 비타민의 신속한 추출 및 분석에 매우 효율적으로 이용될 것으로 기대된다.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.6
• /
• pp.783-790
• /
• 2013

Circular path generation for ball bar measurement using the simultaneous movement of two axes with at least one rotary axis requires the execution of CAM software. However, a change in the machine type or measurement condition requires a new execution of the CAM software, which is cumbersome. This paper presents a circular path generation technique that does not require CAM software and is applicable to different types of driving axes with an arbitrary structural configuration of machine tools and any ball bar setup condition. Mathematical equations are derived for three cases using the proposed technique. In addition, to inspect the measurement feasibility for avoiding physical interference among the ball bar parts, a tilting angle calculation is proposed. The validity of the proposed technique was verified by performing a ball bar experiment with A and C as the simultaneous axes of a five-axis machine tool.

• Journal of KIISE:Databases
• /
• v.30 no.2
• /
• pp.209-224
• /
• 2003

Recent development of electronic commerce enables the use of Electronic Stock Trading Systems(ESTS) to be expanded. In ESTS, information with various sensitivity levels is shared by multiple users with mutually different clearance levels. Therefore, it is necessary to use Multilevel Secure Database Management Systems(MLS/DBMSs) in controlling concurrent execution among multiple transactions. In ESTS, not only analytical OLAP transactions, but also mission critical OLTP transactions are executed concurrently, which causes it difficult to adapt traditional secure transaction management schemes to ESTS environments. In this paper, we propose Secure One Snapshot(SOS) protocol that is devised for Secure Transaction Management in ESTS. By maintaining additional one snapshot as well as working database SOS blocks covert-channel efficiently, enables various real-time transaction management schemes to be adapted with ease, and reduces the length of waiting queue being managed to maintain freshness of data by utilizing the characteristics of less strict correctness criteria. In this paper, we introduce the process of SOS protocol with some examples, and then analyze correctness of devised protocol.

• Analytical Science and Technology
• /
• v.15 no.5
• /
• pp.393-398
• /
• 2002

A method to determine simultaneously fluorene and anthracene in aqueous solution by synchronous fluorescence spectrometry has been studied. The emission characteristics and optimum wavelength interval (${\Delta}{\lambda}$) for synchronous spectra of fluorene and anthracene in aqueous solution were investigated. The optimum wavelength interval (${\Delta}{\lambda}$) was found to be 50 nm. The calibration curve for fluorene and anthracene in the synthetic mixture solution of both compounds was linear over the range from $5.0{\times}10^{-8}M$ to $1.0{\times}10^{-3}M$ and from $5.0{\times}10^{-8}M$ to $1.0{\times}10^{-3}M$ for fluorene and anthracene, respectively. The detection limit was $3.0{\times}10^{-9}M$ and $7.0{\times}10^{-9}M$, for fluorene and anthracene, respectively under the optimal wavelength interval.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.8
• /
• pp.5260-5266
• /
• 2015

To develop weapon system, Concurrent Spare Parts(CSP) is one of the important somethings in terms of Intergrated Logistics System(ILS). CSP is very important to improve the availability of weapon system, and various research about CSP are performed. However, most of the research does not consider the effects between sub-item's failure and weapon system's multiple function. In other words, if sub-item's failure does not seriously influence weapon system's specific function, the point, not necessarily to replace sub-item, is not considered. Therefore, the method to calculate CSP based on above consideration is written by failure-function matrix in this paper. The study follows the procedure below. First, it's to define the operation and maintenance procedure of weapon system. Second, failure-function matrix is developed. Third, simulation model is desinged by input data. Finally, The quantity of CSP is calculated by simulation and evolution strategy, meta-model. This study suggests new research direction to calculate CSP.

• KSBB Journal
• /
• v.18 no.6
• /
• pp.455-460
• /
• 2003

This study was designed to find out the rapid fermentation of soy sauce from koji hydrolyzates using air bubble column reactor packed with coimmobilized mixed culture system. Continuous ripid production was performed by coimmobilized Z. rouxiii BH-90 and C. versatilis BH-91. Coimmobilized cells of Zygosaccharomyces rouxii BH-90 and Candida versatilis BH-91 mixture cells in the column reactor produced 2.8％ ethyl alcohol and 18mg/L 4-ethylguaiacol over 96 hours under the optimal conditions. Coimmobilized cells produced 2.30∼2.4% ethyl alcohol during 30 days, and decreased gradually from 40 days to 70 days. Also coimmobilized cells produced 4-ethylguaiacol at the constant rate of 16∼18mg/L and decreased gradually after 40 days. Final product of soy sauce contained 2.4% ethyl alcohol and 18mg/L 4-ethylguaiacol. However, amino acid compositions of soy sauce were consisted of predominantly glutamic acid, leucin, arginine, aspartic acid, Iysine and valine, which were more than 50% of total amino acid.

• Korean Journal of Construction Engineering and Management
• /
• v.8 no.6
• /
• pp.197-206
• /
• 2007

The age of synthetic correspondence against "development period shortening, high quality" is about to come. While the product is becoming complexation gradually and also diversification, life cycle of product gets shorted. Under the infinity competition age, the certain answer of "the survival of the fittest" is that the enterprise itself must be able to shorten development and delivery term, reduce product development and life cycle cost, and satisfy customer in performance and value. From this point of view, concurrent engineering's theory, which develops the process of product in the manner of repetition, parallel, and synchronousness, is realized as a important strategy instrument in construction. This study investigates and analyzes several examples in order to apply concurrent engineering successfully, and presents the decision-making model through the simulation about the factor affecting in each process.

• Journal of the Korea Society of Computer and Information
• /
• v.11 no.2 s.40
• /
• pp.131-143
• /
• 2006

The rapid growth of mobile communication technology has provided the expansion of mobile internet services, particularly mobile realtime transaction takes much weight among mobile fields. Current mobile transaction service has serious problems which check its development, such as low bandwidths, hand over, expensive charge system, and low response time. but, There is an increasing demand for various mobile applications to process transactions in a mobile computing fields. In mobile computing environments. A mobile host computing system demands for new concurrency control method to use the bandwidth efficiently, to improve the bottleneck and the response time of transactions. This study suggests about an efficient concurrency control in a mobile computing environment. Concurrency control method in existing method uses two phases locking method. In this method, Many clients can't use the same segment simultaneously, and so useless waiting time increases. The characteristic of this proposed method unlike existing one, Enable the transaction approaching different data in the same segment to minimize the useless waiting time by permitting segments, and therefore improves the coexistence of system. Also, It shows the algorithm of the proposed concurrence control method.

• The Korean Journal of Pesticide Science
• /
• v.9 no.4
• /
• pp.311-315
• /
• 2005

The simultaneous or consecutive product analysis is needed for quality control because the various items are produced in pesticide manufacturer. This study was conducted to establish a multi-pesticide analysis making possible to analyze several active ingredients with one injection of mixed active ingredients under same instrument-condition in the cause of quality control with accuracy and speed. The test was conducted with 3 pesticides, iprobenfos 17%GR, isoprothiolane 12%GR, tebufenozide 20%SC and performed by GLC and HPLC. With the GLC method, 2 active ingredients of iprobenfos and isoprothiolane were analyzed but tebufenozide was not detective simultaneously. With the HPLC method, all of the active ingredients in those three pesticides were simultaneously analyzed in this study.