• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.814-821
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• 1999

The specific capacitance characteristics of the electric double layer capacitors(ELDC) which were made of phenol based activated carbon fiber(ACF) electrodes. Also the effect of aqueous electrolytes on the cell performance has been investigated with respect to different specific surface areas of electrodes and different kinds of aqueous electrolytes. It has been shown that larger surface area and pore size, higher conductivity of electrodes, and higher ion mobility of electrolytes have better specific capacitances. It has been found that heat treatment at $1200^{\circ}C$ and $CO_2$ post-activation at $900^{\circ}C$ of the electrode are effective to improve the specific capacitance over 145F/g and 165F/g, respectively. The EDLC showed high efficiency and long cycle life over 30000 cycles.

• Korean journal of applied entomology
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• v.41 no.4
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• pp.255-261
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• 2002

Tomato russet mite, Aculops lycopersici Massee (Acari. Eriophyidae) was recorded in Korea and their SEM observations, distribution, host range, development on different temperature, and chemical control method were studied. Tomato russet mite is a microscopic animal (134.9 $\mu\textrm{m}$) with 2 pairs of legs which had 4 rays of feathered craw. Infected leaf turn reddish brown, stem loss hair, become shiny or surface cross-cracked, and shoot wilted or shrunk. Surface of fruit around fruit stalk appeared rusted or cross-cracked. It was found in glass greenhouse at Buyeo and Yuseong in Chungnam Province, Pyeongchang in Gangwon Province, and Chilgok and Guryongpo in Gyeongbuk Province. Convolvulus, black nightshade, chinese lanternplant, eggp1ant, morning glory, petunia, potato, pepper, tobacco and tomato were confirmed as a host plant in inoculation test. It could develop at temperature around $15-30^{\circ}C$, it took 6-11 days from eggs to adult, higher temperature shorten its life cycle. Female lived longer than male and it lived as long as 12 days at 25-28"C. Among acaricides tested, fenazaquin and cypermethrin were most effective.tive.

• The Journal of Fisheries Business Administration
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• v.46 no.3
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• pp.103-118
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• 2015

The purpose of this paper is to discuss possibilities of applying growth curve models, such as Logistic, Log-Logistic, Log-Normal, Gompertz and Weibull, to three specific technology areas of Fishery Science and Technology in the process of measuring their technology level between Korea and countries with the state-of-the art level. Technology areas of hazard control of organism, environment restoration, and fish cluster detect were selected for this study. Expert panel survey was conducted to construct relevant panel data for years of 2013, 2016, and a future time of approaching the theoretical maximum technology level. The size of data was 70, 70 and 40 respectively. First finding is that estimation of shape and location parameters of each model was statistically significant, and lack-of-fit test using estimated parameters was statistically rejected for each model, meaning all models were good enough to apply for measuring technology levels. Second, three models other than Pearl and Gompertz seemed very appropriate to apply despite the fact that previous case studies have used only Gompertz and Pearl. This study suggests that Weibull model would be a very valid candidate for the purpose. Third, fish cluster detect technology level is relatively higher for both Korea and a country with the state-of-the-art among three areas as of 2013. However, all three areas seem to be approaching their limits(highest technology level point) until 2020 for countries with the state-of-the-art. This implies that Korea might have to speed up her research activities in order to catch up them prior to 2020. Final suggestion is that future study may better apply various and more appropriate models respectively considering each technology characteristics and other factors.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.3
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• pp.410-416
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• 2007

There are many demands for interoperability between weapon systems as the operational needs for joint and coalition based on network in modern and future warfare have been increasingly needed. In DoD, LISI has been applied throughout information system life cycle from the planning phase to the development phase to assess the level of interoperability. We also developed SITES which is a tool to assess the level of interoperability in information systems. But we should extend the assessment model from the previous information systems to the weapon systems to assess the level of interoperability including weapon systems as well as information systems. In this paper, we proposed the assessment model of interoperability, implemented the E-SITE based on the proposed model, applied 12 weapon systems and analyzed the experimental result.

• Journal of the Korean housing association
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• v.22 no.2
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• pp.53-61
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• 2011

This study aims to examine the characteristics of the changes in residents' perception of neighborhood and sense of neighborhood according to the residential structural changes caused by city renewal projects such as old urban large redevelopment. Research findings benefits of the residential environment changes after the development are environment improvement, convenient traffic, leisure activity increase, and green area increase, whereas their drawbacks are encroachment of sunshine and view, However, with the regard to the relationship with neighbors, paired-sample t-test results showed there were no statistically significant differences between before and after the development. It appeared to be that the community residential complex development did not influence the relationship with neighbors. ANOVA was used to examine the differences in the neighborhood perception among age categories. The results showed that there were no differences between age groups but when there were changes in their life cycle, residents showed differences in their neighborhood perception among age groups. The neighborhood perception was measured on 5-point Likert Scale in four factors of intimacy, participation, reliability, and group identity. The perception decreased somewhat after the development and the group identity, especially, showed a significant difference (p<.001). This was considered to be caused by a sense of incongruity due to the influx of different social-economic groups.

• The Transactions of the Korea Information Processing Society
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• v.4 no.2
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• pp.409-429
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• 1997

Problems encountered during software development or pteration nay result from defects in the software,ghrdware,or their oterations.Because of their diversity,the determination of the sources of a problem and its corrective adtion requires a centrally controlled system for monitoring provlems and detemining systematiccauses. In the paper,the SPR/SCR management system was developed and applied for the collection and analysis of the error data,process data and product data delected by each phasd in SDLC.There are four objectibes in the SPR/SCR management system.The first is to assure that software errors are documented,corrected,and vot forgottem. The second is to assure that SPR.are assessed for their validity.The third is to provide feedback on SPR status to the developer and the user.The fourth is ot prvide data for measuring and prediciting sofware quality and reliability.These goals could be satisfied by the application of the SPR/SCR mangement system.Also,the accomplishment rate of software reliability,criterion of test completion,estimation of release time, efficient development and management can be reflected by applying the SPR/SCR management system.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.5
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• pp.259-266
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• 2018

This is the study for developing the hetero-core optical fiber sensors which are purpose to measure the prestress of PSC bridges during the life cycle period. The goal of this study is to improve the resolution of hetero-core sensors. As a result of the test, it is possible to measure the displacement in $2{\mu}m$ increments. In other words, if the length of the sensor module is 30cm, it is possible to measure the prestress variations in 0.2MPa increments at specified compressive strength of concrete(fck) of 40MPa by Hook's Law. So it can be useful for development of a sensor module measuring internal prestress measurement.

• Steel and Composite Structures
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• v.28 no.1
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• pp.39-49
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• 2018

The concrete bridge decks are usually precast and in-situ assembled with steel girders with post-pouring joint in the construction practice of super-wide steel-concrete composite beam. But the difference of concrete age between the precast slabs and the post-pouring joint has been not yet considered for the long-term performance analysis of this kind composite beam. A simply supported precast-assembled T-shaped beam was taken as an example to analyze the long-term performance of steel-concrete composite beam with post-pouring joint. Based on the deformation coordination conditions of the old-new concrete deck and steel girder, a theoretical model for the long-term behavior of precast-assembled composite beam is proposed in this paper according to age-adjusted effective modulus method. Then, the feasibility of the proposed model is verified by the available test data from the Gilbert's composite beams. Parametric studies were preformed to evaluate the influences of the cross-sectional area ratio of the post-pouring joint to the whole bridge deck, as well as the difference of concrete age between the precast slabs and the post-pouring joint, on the long-term performance of the composite beam. The results indicate that the traditional method without considering the age difference would seriously underestimate the effect of creep and shrinkage of concrete bridge decks. The concrete age difference between the precast slabs and the post-pouring joint should be demonstrated for the life cycle design and long-term performance analysis of precast-assembled steel-concrete composite beams.

• Journal of the Korea Society of Computer and Information
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• v.15 no.5
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• pp.125-132
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• 2010

Decision problem called an optimal release policies, after testing a software system in development phase and transfer it to the user, is studied. The applied model of release time exploited infinite non-homogeneous Poisson process. This infinite non-homogeneous Poisson process is a model which reflects the possibility of introducing new faults when correcting or modifying the software. The failure life-cycle distribution used exponential and non-exponential family which has various intensity. Thus, software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement becomes an optimal release policies. In a numerical example, after trend test applied and estimated the parameters using maximum likelihood estimation of inter-failure time data, estimated software optimal release time.

• Korean Journal of Construction Engineering and Management
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• v.12 no.2
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• pp.64-71
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• 2011

Construction projects are becoming larger in size and higher in complexity. Operation and maintenance, therefore, is an important part in providing the serviceability of the built facility from the perspective of life-cycle. This paper presents a 3D graphic model-integrated data extraction for bridge maintenance. The 3D graphic model environment assigns attributes to the member blocks in CAD, and link the attributes to the data stored in a database. Then, the user can click the member block to extract the data associated with the attributes. A prototype has been developed to test the applicability of the 3D graphic model environment using CAD and web. Application of the system in an actual bridge construction showed that the 3D graphic model environment can help the user find necessary data at a shorter time, thereby increasing the effectiveness of operation and maintenance in bridge structures.