• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9C
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• pp.908-922
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• 2003

The Public Key Infrastructure (PKI) trends to delegate the certificate path processing to the Delegated Path Discovery (DPD) Server and Delegated Path Validation (DPV) server recently. The most critical factor for the selection of the delegated server is to allow the server to be equipped with a high reliability through a low cost, and simple implementation. In this paper, we propose a new certificate path processing scheme employed the trusted CA as the DPD/DPV server by adding the capability of the Validation Authority (VA) to the trusted CA. Since our proposed scheme uses the existing trusted CA as validation server, we can achieve a high trust through a simple implementation for the processing. Besides, we propose an additional scheme for reducing an overhead on the trusted CA. it is obtained by delegating digital signature verification to CAs on the path and by skipping the repeated path processing. As the result, our proposed validation scheme can be performed efficiently with high speed and low computational overhead.

• Convergence Security Journal
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• v.11 no.6
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• pp.73-80
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• 2011

In this study, software products developed in the course of testing, software managers in the process of testing software and tools for effective learning effects perspective has been studied using the NHPP software. The delayed software S-shaped reliability model applied to distribution was based on finite failure NHPP. Software error detection techniques known in advance, but influencing factors for considering the errors found automatically and learning factors, by prior experience, to find precisely the error factor setting up the testing manager are presented comparing the problem. As a result, the learning factor is greater than automatic error that is generally efficient model could be confirmed. This paper, numerical example of applying using time between failures and parameter estimation using maximum likelihood estimation method, after the efficiency of the data through trend analysis model selection were efficient using the mean square error and $R^2$(coefficient of determination).

• Korean Journal of Construction Engineering and Management
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• v.12 no.5
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• pp.55-62
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• 2011

Recently, construction work has diversified and become larger. So, a systematic measurement and management measures are required. In this study, USN technology which is one of the most important network technologies was selected. Based on elements derived from comparison of each element of standard was calculated according to the importance of the elements. The importance of the decision to support the proposed model is explained by integrating the importance of each criteria and decision-support model by considering the situation and creating a matrix of considerations for the construction of earthwork. The results of this study show that USN technology in the context of judging criteria can be selected for the earthwork.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.5
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• pp.80-86
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• 2010

The conventional bus system architecture consists of masters, slaves, arbiter, decoder and so on in shared bus. As several masters can't use a bus concurrently, arbiter plays an role in arbitrating the bus. The efficiency of bus usage can be determined by the selection of arbitration method. Fixed Priority, Round-Robin, TDMA and Lottery arbitration policies are studied in the conventional arbitration method where the bus priority is primarily considered. In this paper, we propose the arbitration method that calculates the bus utilization of each master. Furthermore, we verify the performance compared with the other arbitration methods through TLM(Transaction Level Model). From the results of performance verification, the arbitration methods of Fixed Priority and Round-Robin can not set the bus utilization and those of TDMA and Lottery happen the error of 50% and 70% respectively compared with bus utilization set by user in more than 100,000 cycles. On the other hand, the bandwidth-award bus arbitration method remains the error of less than 1% since approximately 1000 cycles, compared with bus utilization set by user.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.4
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• pp.1-9
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• 2007

in this paper, we propose the Adaptive Decision Algorithm for RFID Tag Anti-Collision. We study the RFID Tag anti-collision technique of ALOHA and the anti-collision algorithm of binary search. The existing technique is several problems; the transmitted data rate included of data, the recognition time and energy efficiency. For distinction of all tags, the Adaptive Decision algorithm identify smaller one ,each Tag_ID bit's sum of bit '1'. In other words, Adaptive Decision algorithm had standard of selection by actively, the algorithm can reduce unnecessary number of search even than the exisiting algorithm. The Adaptive Decision algorithm had performance test that criterions were reader's number of repetition and number of transmitted bits for understanding tag. We showed the good performance of Adaptive Decision algorithm better than exisiting algorithm.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.159-164
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• 2001

An extensive range of pumping facilities are employed in the regional water supply system in metropolitan areas, and optimization and the systematic combination of the pump facilities have direct bearing on the stability and economy of the water supply system concerned. These systems must be able to guarantee stability, efficiency and offer high reliability. Preparation of metropolitan area regional water supply system construction project must include a basic plan which takes into account the suitability of pumping facilities to be used, the environment in which facilities will be installed, man-power requirements and basic operational and management policies. This paper contains over-all analysis of the management of metropolitan area regional water supply systems and highlights the cause of Inefficiency and energy waste and puts forward a remedial plan of action. In addition, pump/motor specification programs were developed using Visual Basic to assist selection of the same.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.179-183
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• 2009

To facilitate the genetic manipulation of Cladosporium phlei, a causal agent of leaf spot disease in timothy (Phleum pretense), protoplast-mediated transformation of C. phlei has been developed and the resulting transformants were characterized in this study. Hygromycin B resistance was applied as a dominant selection marker due to the sensitivity of C. phlei to this antibiotic. The transformation efficiency ranged from approximately 20-100 transformants per experiment. Southern blot analysis of stable transformants revealed that transformation occurred by way of stable integration of the vector DNA into the fungal chromosome. PCR analysis and plasmid rescuing of randomly selected transformants suggested that integration of tandem repeat copies of vector DNA was common. In addition, multiple integrations of the transforming vector at different chromosomal sites were also observed. The establishment of a transformation method for C. phlei facilitates strain improvement of this fungus and can be applied as an initial step in the molecular analysis of pigment production in this fungus.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.5
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• pp.437-441
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• 2014

This paper presents a novel microplatform for high power generation based on reverse electrodialysis. The ideal cation-selective membrane for power generation was realized using geometrically controlled in situ self-assembled nanoparticles. Our proposed membranes can be constructed through a simple and cost-effective process that uses microdroplet control with nanoparticles in a microchannel. Another advantage of our system is that the maximum power and energy conversion efficiency can be improved by changing the geometry of the microchannel and proper selection of the nanoparticle size and material. This proposed platform can be used to supply power sources to other microdevices and contribute to a fundamental understanding of ion transport behavior and the power generation mechanism.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.6
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• pp.2398-2421
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• 2020

In third world countries like Pakistan, the production of electricity has been quickly reduced in past years due to rely on the fossil fuel. According to a survey conducted in 2017, the overall electrical energy capacity was 22,797MW, since the electrical grids have gone too old, therefore the efficiency of grids, goes down to nearly 17000MW. Significant addition of fossil fuel, hydro and nuclear is 64.2%, 29% and 5.8% respectively in the total electricity production in Pakistan. In 2018, the demand crossed 20,223MW, compared to peak generation of 15,400 to 15,700MW as by the Ministry of Water and Power. Country faces a deficit of almost 4000MW to 5000MW for the duration of 2019 hot summer term. Focus on one aspect considering Demand Side Management (DSM) cannot oversea the reduction of gap between power demand and customer supply, which eventually leads to the issue of load shedding. Hence, a scheduling scheme is proposed in this paper called RPSMDSM that is based on selection of those appliances that need to be only Turned-On, on priority during peak hours consuming minimum energy. The Home Energy Management (HEM) system is integrated between consumer and utility and bidirectional flow is presented in the scheme. During peak hours of electricity, the RPSMDSM is capable to persuade less power consumption and accomplish productivity in load management. Simulations show that RPSMDSM scheme helps in scheduling the electricity loads from peak price to off-peak price hours. As a result, minimization in electricity cost as well as (Peak-to-Average Ratio) PAR are accomplished with sensible waiting time.

• Clinical and Experimental Reproductive Medicine
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• v.18 no.1
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• pp.95-99
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• 1991

Swim-up and Wang's tube system are known methods of motile sperm selection and aerobic bacterial removal from the raw semen. This study was designed to evaluate the recovery rate of motile sperm, % normal morphology of sperm, the efficiency of bacterial removal after sperm preparation by the above two methods. The results were as follows. 1. There was more significant increase of sperm concentration in preparation by swim-up than Wang's tube (p<0.05). The concentration of sperm by swim up was changed from $82.5{\times}10^6/ml$ to $6836{\times}10^6/ml$, and Wang's tube was changed from $82.5{\times}10^6/ml$ to $36.0{\times}10^6/ml$. 2. There was significant increase in sperm motility after preparation by two methods in comparison with initial sperm motility (p<0.05), but no statistical difference between two methods was noted. The % motility of sperm by swim-up was increased from 66.1% to 95.7% and Wang's tube from 66.1% to 98.1%. 3. There was significant increase of % normal morphology of sperm in the samples prepared by two methods (p<0.05), from 49.2% to 85.3% in swim-up and from 49.2% to 92.1% in Wang's tube, but there was no statistical significance between them. 4. There was no bacterial growth in aerobic culture after preparation by two methods.