• Journal of the Korea Society of Computer and Information
• /
• v.18 no.4
• /
• pp.131-140
• /
• 2013

This paper deals with the design and implementation of an interface for interoperation between DiskSim, a well-known disk simulator, and a system-level simulator based on DEVSim++. Such inter-operational simulation aims at evaluation of an overall performance of storage systems which consist of multiple computer nodes with a variety of I/O level specifications. A well-known system-level simulation framework, DEVSim++ environment is based on the DEVS formalism, which provides a sound semantics of modular and hierarchical modeling methodology at the discrete event systems level such as multi-node computer systems. For maintainability we assume that there is no change of the source codes for two heterogeneous simulation engines. Thus, we adopt a notion of simulators interoperation in which there should be a means to synchronize simulation times as well as to exchange messages between simulators. As an interface for such interoperation DiskSimManager is designed and implemented. Various experiments, comparing the results of the standalone DiskSim simulation and the interoperation simulation using the proposed interface of DiskSimManager, proved that DiskSimManager works correctly as an interface for interoperation between DEVSim++ and DiskSim.

• KIPS Transactions on Software and Data Engineering
• /
• v.5 no.5
• /
• pp.203-208
• /
• 2016

Information system audit is the requirement to configure the information system successfully. However, there is a problem with reduction of efficiency in the audit work when the system capacity is growing up. In the subsidiary field of information system audit, there is the same problem. In this paper, we will focus on the database audit, and implement an SQL audit tool in order to improve the performance of a database. During the designing phase of the SQL audit tool which aim to improve the performance of a database, we have analyzed the requirements of SQL audit work. Based on the aforementioned them, the process of the SQL audit tool has been designed with SQL audit features in accordance with information audit process. During the implementation phase, we have implemented 3 main function modules according to the output of the design phase. The main modules we implemented are the audit job definition module, audit job executing module and result reporting module. With the implemented tool, it applied to an Electric Power Corporation project in China and compared with other tools that are able to use SQL audit. In this paper, the implemented SQL audit tool is able to perform the general SQL audit work and to reduce the cost of the audit work for database performance and to raise the accuracy of result and to apply the extended inspection rule which need to use SQL parsing.

• Journal of the Korea Society of Computer and Information
• /
• v.18 no.9
• /
• pp.21-31
• /
• 2013

ECU(Electric Control Unit) on the important features of the vehicle is equipped, ECU between sending and receiving messages is connected to one of the internal network(CAN BUS), but this network easily accessible from the outside and not intended to be able to receive attacks from an attacker, In this regard, the development of tools that can be used in order to verify the possibility of attacks on attacks from outside, However, the time costs incurred for developing tools and time to analyze from actual car for CAN messages to be used in the attack to find. In this paper, we want to solve it, propose a method to generate test cases required for the attack is publicly available tool called Sulley and it explains how to find the CAN messages to be used in the attack. Sulley add the CAN messages data generated library files in provided library file and than Sulley execute that make define and execute file conform to the CAN communication preferences and create message rules. Experiments performed by the proposed methodology is applied to the actual car and result, test cases generated by the CAN messages fuzzing through Sulley send in the car and as a result without a separate tool developed was operating the car.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.11
• /
• pp.5578-5586
• /
• 2012

The accurate estimation of discharge is very essential as the important factor of river design for the utilization and flood control, hydraulic construction design. The present discharge production is using the stage-discharge relationship curve in the river. The rating curve uses the method by predicting the discharge based on regression analysis using the measured stage and discharge data in a flood season. The method is comparatively convenient and has especially advantages in that it can predict the discharge having the difficulty of observation in a flood season. However, this method has basically room for improvement because the method only uses the relationship between stage and discharge, and doesn't reflect the hydraulic parameters such as hydraulic radius, energy slope, roughness, topography, etc.. Therefore, in this study, discharge was predicted using the convenient calculation method with empirical parameters of the Manning and Chezy equations, which were proposed by Choo et at (2011) in KSCE as a new methodology for estimating discharge in open channel. The proposed method can conveniently estimate empirical parameters in both of Manning and Chezy equations and the discharge is estimated in the open channels. There are proved by using data measured in meandering lab. channel and India canal and the accuracies show about determination coefficient 0.8. Accordingly, this method will be used in actual field if this study is continuously conducted.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.6
• /
• pp.325-331
• /
• 2020

Even though numerous studies on the relationship between high-performance work systems (HPWSs) and organizational performance have been conducted over the past three decades, empirical evidence is still lacking in the aspects of context and performance. Thus, this study aims to investigate how HPWSs influence organizational performance, especially innovation performance as a key factor to increase the organization's sustainability. In addition, this study examines how human competency and customer service competency as crucial conditions to facilitate organizational innovation moderate the relationship between HPWSs and organizational performance. To examine these hypotheses, this study used Human Corporate Capital Panel datasets. The results of longitudinal analyses show that HPWSs positively affected organizational performance, and the two competencies strengthened the positive main effect, as we expected. In the discussion parts, this study suggests implications and limitations.

• The KIPS Transactions:PartC
• /
• v.16C no.4
• /
• pp.461-476
• /
• 2009

Digital Printers that are mainly used in enterprises and public institutions are compound machinery and tools which are combined into various functions such as printing, copying, scanning, and fax so on. Digital Printers has security functionality for protecting the important data related with confidential industry technology from leaking. According to the trends, CC(Common Criteria) evaluation and assurance about digital printer is on progress in Japan and USA. Domestically CC evaluation and assurance is started recently. However, the know-how about the digital printer evaluation is not enough and the developers and the evaluators have difficulty in CC evaluation of digital printer products in the country. Therefore, the testing method of digital printer security functionality and evaluation technology is essentially needed for increasing demand for the evaluation afterwards. In this study, we analyze the security functionality and developing trends of digital printer products from internal and external major digital printer companies. Moreover, we research the characters of each security functions and propose guideline for digital printer security functionality evaluation and vulnerability testing methods.

• Clinical and Experimental Pediatrics
• /
• v.52 no.9
• /
• pp.999-1004
• /
• 2009

Purpose : Glomerular filtration rate (GFR) is a fundamental parameter in assessing renal function and predicting the progression of chronic renal disease. Because the use of serum creatinine has several disadvantages, many studies have investigated the use of cystatin C for estimating GFR. We compared creatinine clearance and GFR with formulas using serum creatinine and cystatin C. Methods : We retrospectively analyzed 211 patients with various renal diseases and classified them into two groups according to creatinine clearance (Group 1: CrCl >$90mL/min/1.73m^2$, Group 2: CrCl <$90mL/min/1.73m^2$). We measured serum creatinine, cystatin C, and creatinine clearance. We calculated GFR using the Schwartz, Counahan, Filler and Lepage, Bokencamp et al, and Grubb et al formulas. Results : GFR determined by the Schwartz formula had the highest correlation to creatinine clearance (r=0.415, P=0.00). GFR determined by various formulas using cystatin C had lower correlation to creatinine clearance (r=0.187, r=0.187, r=0.291). The Schwartz and Counahan formulas showed greater diagnostic accuracy in detecting decreased GFR than cystatin C in group 2 (areas under the curve: Schwartz, 0.596; Counahan, 0.572; Filler, 0.512; Bokencamp, 0.508; and Grubb, 0.514). Conclusion : GFR determined by the Schwartz and Counahan formulas using serum creatinine showed higher correlation coefficient than that determined by formulas using cystatin C. The formulas using cystatin C were not superior to those using serum creatinine in detecting decreased GFR. Cystatin C measurement was not satisfactory for assessing GFR in patients whose renal function was not severely decreased.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.7
• /
• pp.33-38
• /
• 2017

The number of damaged lifeline structures have been increasing with urban acceleration under earthquakes. To predict the damage, damage mitigation technology of lifeline structures should be analyzed using damage prediction technology. Therefore, in this paper, the degree of the fragility of structures under an earthquake was evaluated stochastically through an evaluation of the seismic fragility. The aim was to develop damage prediction technology of sewage pipes among the lifeline facilities. The site response was performed using the data from 158 boreholes in Seoul and 7 real earthquake waves to determine the responses in real urban areas. The seismic fragility was deduced through a total of 29822 time history analysis. In addition, sewer pipes were evaluated and the persisting period was passed by applying the research results of strength reduction which is due to sulphate erosion. As a result, the difference in failure probability between 300 and 800 with the smaller diameter of the representative pipes was approximately double and the size of the pipes has a significant effect on the seismic fragility function. Moreover, the failure probability of a seismic load increases by up to 10 fold as the strength reduction rate increases. The results of this study can be used as a means of predicting the damage and countermeasures of sewer pipes and might be reflected in the seismic design of underground facilities.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.4
• /
• pp.1468-1474
• /
• 2010

The establishment of a successful business must be preceded by comprehensive entrepreneurial preparation and research, as well as the development of a truly attractive business idea. Research to-date has tended to be based solely on factors relating to entrepreneurial activity or business performance. Research into the development and evaluation of a business idea has been insufficient. The purpose of this research is to propose a methodology for evaluating the attractiveness of a business idea objectively. This research measures the attractiveness of a business idea by the click through rate (CTR) to a website generated by specific keyword entry into internet search engines. The attractiveness of a business idea can be presented by the formula: number of relevant keyword searches x CTR on search results. As the number of searches for individual keywords is published by the search engines and it is possible to estimate CTRs for specific search results, we can objectively evaluate the attractiveness of a business idea. By analyzing keyword search data and CTRs obtained from search engines over a one month period, 1124 keywords that relate to foreign language education have been identified. A regression formula has also been derived, predicting the click through rate for search results. This research and its findings can be used to raise the success rates of new businesses; proposing objective guidelines for business idea development and evaluation. It is particularly meaningful because it introduces a new methodology to the arena.

• Journal of Navigation and Port Research
• /
• v.36 no.6
• /
• pp.521-526
• /
• 2012

More efficient and effective volume management of trade cargo is recently requested due to FTA with foreign country. Above all, the grain is the main cargo needed in Korean food life and was appointed as the core trade cargo during FTA. This study is aimed to forecast future demands of grain volumes which are handled at Incheon port because most of the grain volumes are traded at Incheon port in Korea. System Dynamics (SD) was used for forecasting as the methodology. Also, population, yearly grain consumption per a man, GDP, GRDP, exchange rate, and BDI were used as the factors that influence grain volumes. Simulation duration was from 2000 to 2020 and real data was used from 2000 to 2007. According to the simulation, 2020's grain volumes at Incheon port were forecasted to be about 2 million tons and grain volumes handled at Incheon port were continuously reduced. In order to measure accuracy of the simulation, this study implemented MAPE analysis. And after the implementation, the simulation was decided as a much more accurate model because MAPE value was calculated to be 6.3%. This study respectively examined factors using the sensitivity analysis. As a result, in terms of the effects on grain volume in Incheon Port, the population factor is most significant and exchange rate factor is the least.