• Nuclear Engineering and Technology
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• v.44 no.6
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• pp.697-708
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• 2012

The majority of instrumentation and control (I&C) systems in today's nuclear power plants (NPPs) are based on analog technology. Thus, most existing I&C systems now face obsolescence problems. Existing NPPs have difficulty in repairing and replacing devices and boards during maintenance because manufacturers no longer produce the analog devices and boards used in the implemented I&C systems. Therefore, existing NPPs are replacing the obsolete analog I&C systems with advanced digital systems. New NPPs are also adopting digital I&C systems because the economic efficiencies and usability of the systems are higher than the analog I&C systems. Digital I&C systems are based on two technologies: a microprocessor based system in which software programs manage the required functions and a programmable logic device (PLD) based system in which programmable logic devices, such as field programmable gate arrays, manage the required functions. PLD based systems provide higher levels of performance compared with microprocessor based systems because PLD systems can process the data in parallel while microprocessor based systems process the data sequentially. In this research, a bistable trip logic in a reactor protection system (RPS) was developed using very high speed integrated circuits hardware description language (VHDL), which is a hardware description language used in electronic design to describe the behavior of the digital system. Functional verifications were also performed in order to verify that the bistable trip logic was designed correctly and satisfied the required specifications. For the functional verification, a random testing technique was adopted to generate test inputs for the bistable trip logic.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.957-965
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• 2006

This research was conducted to examine the usability of Dangui (Angelica gigas Nakai, Root) and Seungumcho (Angelica gigas Nakai, Leaf) as functional food in aspects of their functional components and nitrite scavenging ability. Analysis of proximate composition showed that Dangui contains more moisture, crude lipid and crude protein than Seungumcho. On the other hand, Seungumcho contains more than twice mont of crude ash and crude fiber than Dangui. Dangui showed higher contents in phosphorus, iron, magnesium, and Seungumcho showed higher contents in copper, calcium, sodium, potassium compare to each other. Substances such as calcium, magnesium and iron that showed high contents in Dangui and Seungumcho are the most important inorganic substances. Total dietary fiber(TDF) of Dangui, sum of IDF and SDF, was 24.2%, and Seungumcho showed 28.18%. vitamin C contents of a 29.690.33 mg/100g appeared only in Seunggumcho. Total phenol contents of Dangui was 0.100${\pm}$002% and that of Seungumcho 0.0900${\pm}$008%. Nnitrite Scavenging ability of both water soluble and methanol soluble extracts were more than 90% at pH 1.2, and it decreased as pH level adjusted to pH 4.2, pH and 6.0.

• Journal of the Korean Institute of Rural Architecture
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• v.18 no.4
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• pp.17-24
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• 2016

Since the users have direct access to search and browse freely, the open access system has been employed to all the usual modern libraries. However, library space shortage problem created by the continuously increasing printed materials caused the degradation of usability and quality of the library space. Open Access system is superior in user convenience but is inferior in space efficiency. Keeping the open access system is considered as one of the reasons of the space shortage problem. Even though the closed access system does not provide free access or easy browsing for the uses, it's space efficiency is much higher than the open access system. The closed access system should be employed as a plan to relieve space shortage problem. Since the closed access system does not allow the public direct access to books, it is very economical. It also provides much better space efficiency with higher book shelving density. In this article, closed access library system models and their characteristics are examined as the reduction plans for the library space shortage problems.

• Asian Journal of Turfgrass Science
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• v.13 no.4
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• pp.201-212
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• 1999

In use of pesticides in golf courses has been increased steadily. Environmental concern as well as decrease in efficiency led the turfgrass management into an alternate approach of using beneficial microorganism to deal with turfgrass pests. This study was focused on the use of such microorganisms for improving cultural environment and minimizing the use of pesticides. Microorganisms antagonistic to turfgrass diseases were applied to zoysiagrass fairways and creeping bentgrass greens in Yusung country club. Tharch accumulation, disease occurrence, and other cultural environments were compared among the combinations of microorganisms and suppliemental N applications. The application of microorganisms antagonistic to turfgrass diseases improved turf resiliency. Thatch thickness was 3.03cm in the control plot but it was 2.11cm in plots treated by microorganisms, indicating significant effects of microorganism application on reduction of thatch accumulation. Number of microorganism that can decompose of cellulose was higher at the plots treated with useful microbial products and it was considered that existence of higher population of microorganisms resulted in reduction of thatch accumulation. In the evaluation of relationship between thatch accumulation and disease occurrence, greater thatch accumulation was observed at the golf courses which have been frequently infested by large patch. However, the rate of thatch accumulation varied among surveyed golf courses regardless of the year of turf establishment. Therefore, management practice which can be effective for reduction of thatch could result in large patch suppression. The application of microorganisms on the established turfgrasses reduced the occurrence rate of pythium blight and yellow path diseases, whereas occurrence of brown patch and dollar spot increased.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.11
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• pp.5234-5251
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• 2018

It is well-known that virtualization technology can bring many benefits not only to users but also to service providers. From the view of system security and resource utility, higher resource sharing degree and higher system reliability can be obtained by the introduction of virtualization technology in distributed cloud. The small size time-sharing multiplexing technology which is based on virtual machine in distributed cloud platform can enhance the resource utilization effectively by server consolidation. In this paper, the concept of memory block and user satisfaction is redefined combined with user requirements. According to the unbalanced memory resource states and user preference requirements in multi-virtual machine environments, a model of proper memory resource allocation is proposed combined with memory block and user satisfaction, and at the same time a memory optimization allocation algorithm is proposed which is based on virtual memory block, makespan and user satisfaction under the premise of an orderly physical nodes states also. In the algorithm, a memory optimal problem can be transformed into a resource workload balance problem. All the virtual machine tasks are simulated in Cloudsim platform. And the experimental results show that the problem of virtual machine memory resource allocation can be solved flexibly and efficiently.

• Journal of the Korean Wood Science and Technology
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• v.32 no.6
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• pp.7-13
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• 2004

In this study, the Korean pine wood (Pinus densiflora Sieb. et Zucc) and Italian poplar wood (Populus euramericana Guinier) was treated with a mixture of monoammonium phosphate (MAP) and boric acid. Their usability as fire retardant and as decay-resistant construction and interior materials were evaluated by testing of chemicals, corrosion rate and absorption rate, weight loss and chemical contents. An experiment was performed to compare treated pine wood and Italian poplar wood. According to the results, Italian poplar wood had higher specific gravity and retention of chemicals than pine wood, and treated wood showed higher decay-resistance than untreated one. Weight loss was less in treated wood than untreated one because the degree of decay was lower in the former than the latter. Corrosion rate and absorption rate met the KS standard for wood preservative performance. The chemical contents analysis was carried out to determine the degree of decay and it was found that the preservative effect of chemical treatment was lower in Italian poplar wood than in pine wood.

• Journal of Soil and Groundwater Environment
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• v.28 no.5
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• pp.68-77
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• 2023

The effect of soil damage on the physicochemical characteristics and activity of the soil microbial community is not well known. This study investigates this relationship by analyzing 11 soil samples collected from various points of soil damage across Gyeonggi-do. Soil damage resulted from forest fires, landslides, and development areas, with their impacts most severe on the topsoil layer (0-30 cm). Dehydrogenase and β-glucosidase activities were notably higher at locations damaged by forest fires compared to other sites. While enzyme activities in soils influenced by landslides and development areas were relatively low, sites with a pollution history exhibited elevated dehydrogenase activity, likely due to past microbial response to the pollution. Additionally, an assessment of carbon substrate usability by soil microorganisms indicated higher substrate availability in areas impacted by forest fires, contrasting with lower availability in landslide and development sites. Statistical analysis revealed a positive correlation between organic content of sand and clay and microbial activity. These findings provide valuable insights into soil damage and associated restoration research, as well as management strategies.

• Journal of the Ergonomics Society of Korea
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• v.25 no.2
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• pp.173-180
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• 2006

An ergonomic study of school environment and school desks and chairs was conducted in Incheon metropolitan area. Total of 1,145 students from 11 schools participated in questionnaire survey and ergonomic evaluation of school desks and chairs was performed to study structural appropriateness and usability. Results of the study revealed that overall levels of school environment in terms of noise and dust density in the air were higher than safety standard. Desks and chairs were not properly designed with consideration of student's anthropometric characteristics. Prompt improvement of school environment and re-designing of school furniture are required in order to prevent reduced performance in study and physical disorders such as musculoskeletal disorders.

• International journal of advanced smart convergence
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• v.8 no.4
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• pp.200-206
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• 2019

In this study, we compared the VacCAD and VacSim^(Multi), commercial vacuum simulators, to verify the advantages of VacCAD's efficiency. It was emphasized on immediacy and simplicity of simulation modelling, and characteristics of the pump combinations, pumping down curves, and vacuum materials. First, usability of simulation mechanism was estimated through the modeling schematics and obtained simulation results of each employed simulator were compared to evaluate the applicability in practice. Simulation reliability of each simulator was also probed by comparing the pumping characteristics of commercially available high vacuum systems. In addition, the degree of tolerances on VacCAD was also investigated through pumping down analysis considering outgassing effect due to chamber material variations. The higher effectiveness and expediency of VacCAD than VacSim^(Multi) has been presented, and it was expected that the utilization of VacCAD in vacuum applications to be increased.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04c
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• pp.16-18
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• 2003

웹서비스는 개방성.호환성.재활용성.유연성등 이기종 시스템간의 호환성이 뛰어나 분산연동을 위한 차세대 대안책으로 급부상하고 있다. 또한, XML을 기반으로하여 개발언어나 플랫폼에 종속되지 않고 다수의 개발업체가 참여하여 핵심 표준(SOAP, WSDL, UDDI)이 폭넓게 수용되고 채택돼 동적인 연동을 통한 분산 서비스를 지원한다. 그러나, 실제적으로는 요청체계에서 서비스 서버의 고정화로 인해 동적인 연동이 제한을 받는다는 것은 주지의 사실이다. 본고에서는 고정된 지원서버의 서비스제공이 불가한 경우에서도 유사도 개념을 도입한 UDDI의 유사 시스템을 제공할 수 있는 지능형 동적바인딩을 제안한다.