• Title/Summary/Keyword: EXTENSIVE MANAGEMENT

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Competitiveness of Formic Acid Fuel Cells: In Comparison with Methanol (포름산 연료전지의 경쟁력)

  • Uhm, Sunghyun;Seo, Minhye;Lee, Jaeyoung
    • Applied Chemistry for Engineering
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    • v.27 no.2
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    • pp.123-127
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    • 2016
  • Methanol fuel cells having advantages of relatively favorable reaction kinetics and higher energy density have attracted increasing interests as best alternative to hydrogen fuel cell because of H2 production, storage and distribution issues. While there have been extensive research works on developing key components such as electrocatalysts as well as their physicochemical properties in practical formic acid fuel cells, there have also been urgent requests for investigating which fuel sources will be more suitable for direct liquid fuel cells in future. In this mini-review, we highlight the overall interest and outlook of formic acid fuel cells in terms of electrocatalysts, fuel supply and crossover, water management, fuel cell efficiency and system integration in comparison with methanol fuel cells.

A Study on the Convergence of Monitoring and Control System with Geographic Information System (지리정보시스템과 관제시스템의 융합에 관한 연구)

  • Seo, Tae-Woong;Kim, Chang-Soo;Lee, Jae-Sung;Lee, Cheol-Won
    • Journal of Korea Multimedia Society
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    • v.14 no.5
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    • pp.703-709
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    • 2011
  • State-based infrastructure on IT-based network are prone to numerous cyber attack including subsequent hacking and internet infringement. These acts of terrorism are increasing because of the expanding IT convergence technology. Recently, the trend on cyber security monitoring and control researches focus on combining the general idea of security monitoring and control along with IT field and other control systems. This convergence trend has been increasing in both the use and importance. This research analyzes the state-based infrastructure monitoring and control system, its vulnerability as well as its improvement by incorporating the cyber convergence systems to existing systems. The subject of this research is for extensive use of CCTV systems which is expanded for 'CCTV Monitoring and Control Field' as well as 'Traffic Monitoring and Control Field' operated by 'Intelligent Traffic Information System' and Disaster Management Area which is studied in various fields. Eventually, the objective of the paper is to solve these issues, to apply related systems and to suggest improvement on the convergence system.

Effect of [6] -Gingerol on Inhibition of Cell Proliferation in MDA-MB-231 Human Breast Cancer Cells ([6]-Gingerol이 인체 유방암세포인 MDA-MB-231의 세포증식 억제에 미치는 영향)

  • Seo Eun-Young;Lee Hyun-Sook;Kim Woo-Kyung
    • Journal of Nutrition and Health
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    • v.38 no.8
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    • pp.656-662
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    • 2005
  • Ginger (Zingiber of oficinale Roscoe, Zingiberaceae) is one of the most frequently and heavily consumed dietary condiments throughout the world. Besides its extensive use as a spice, the rhizome of ginger has also been used in traditional oriental herbal medicine for the management of symptoms such as common cold, digestive disorders, rheumatism, neurologia, colic, and motion-sickness. The oleoresin from rhizomes of ginger contains [6] -gingerol (1- [4'-hydroxy-3'-methoxyphenyl]-5-hydroxy-3-decanone) and its homologs as pungent ingredients that have been found to possess many interesting pharmacological and physiological activities, such as anti-inflammatory, analgesic, antipyretic, antiheatotoxic, and cardiotonic effects. However, the effect of [6]-gingerol on cell proliferation in breast cancer cell are not currently well known. Therefore, in this study, we examined effect of [6]-gingerol on protein and mRNA expression associated with cell proliferation in MDA-MB-231 human breast. cancer cell lines. We cultured MDA-MB-231 cells in presence of 0, 2.5, 5 and $10{\mu}M$ of [6] -gingerol. [6]-Gingerol inhibited breast cancer cell growth in a dose-depenent manner as determined by MTT assay. ErbB2 and ErbB3 protein and mRNA expression were decreased dose-dependently in cells treated with [6]-gingerol (p<0.05). In addition, phosphorylated Akt levels and total hぉ levels were markedly decreased in cells treated with $2.5{\mu}M$ [6]-gingerol (p<0.05). In conclusion, we have shown that [6]-gingerol inhibits cell proliferation through ErbB2 and ErbB3, reduction in MDA-MB-231 human breast cancer cell lines.

Percutaneous Vertebroplasty with Polymethymethacrylate in the Treatment of Osteoporotic Vertebral Body Compression Fractures : Preliminary Report (폴리메틸메타크리레이트를 사용한 경피적 척추성형술의 골다공증 척추체 압박골절에 대한 치료효과 : 예비보고)

  • Park, Chun Kun;Lee, Kwan Sung;Choi, Yung Gun;Ryu, Kyung Sig;Park, Choon Keun;Cho, Kyung Suck;Kang, Joon Ki
    • Journal of Korean Neurosurgical Society
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    • v.29 no.3
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    • pp.365-371
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    • 2000
  • Objectives : To describe a technique for percutaneous vertebroplasty of osteoporotic vertebral body compression fractures and to report preliminary results of its use. Methods : The technique was used over a 8-month period in 9 patients with 10 painful vertebral fractures. The technique involves percutaneous puncture of the involved vertebrae with a Jamshidi needle via a transpedicular approach followed by injection of polymethylmethacrylate(PMMA) into the vertebral body. Results : The procedure was technically successful in all patients, with an average injection amount of 5.9 cc per vertebral body. One patient complained of flank pain postoperatively in spite of improvement in back pain caused by the fractured vertebra. Remaining eight patients reported significant pain relief early after treatment. The patients were followed up for 3 to 15 months(average 7.2 months) and demonstrated no recurrence of pain or aggravation of deformity. Conclusion : Vertebroplasty appears to be a valuable tool in the treatment of painful osteoporotic vertebral fractures, providing acute pain relief and early mobilization in appropriate patients. However, it needs to have more extensive prospective clinical study to confirm its definitive role in the management of this condition.

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Estimating User Utility Functions for Network-Resource Pricing (네트워크 자원 가격정책을 위한 사용자 유틸리티 함수 추정법)

  • Park, Sun-Ju
    • Journal of KIISE:Information Networking
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    • v.33 no.1
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    • pp.103-112
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    • 2006
  • Priority-based network service has been widely adopted for the Internet traffic management in the context of IETF differentiated services, and computing optimal prices for such priority-based service is the key topic in many pricing literature. While the equilibrium analysis has been commonly used to this end, many have criticized the validity of the underlying assumption of equilibrium analysis that user utility functions are precisely known. In this paper, we propose a solution for bridging the gap between the existing theoretical work on optimal pricing and the unavailability of precise user utility information in real networks. In the proposed method, the service provider obtains more and more accurate estimates of user utility functions from the initial imprecise knowledge by iteratively changing the price of service levels and observing the users' decisions under the changed price. Our contribution is two-fold. First, we have developed a general principle for estimating the user utility functions. Second, we have developed a novel method for setting the prices that can optimize the extraction of the knowledge about user utility functions. The extensive simulation results demonstrate the effectiveness of our method.

Optimal Effort Allocation in Software Development Phase (소프트웨어 개발 단계별 최적의 노력 할당)

  • 박재흥;노명옥;하석운
    • Journal of the Korea Computer Industry Society
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    • v.3 no.3
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    • pp.295-306
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    • 2002
  • Successful project planning relies on a good estimation of the effort required to complete a project, together with the schedule options that may be available. Despite the extensive research done developing new and better models, existing software effort estimation models are present only the total effort and instantaneous effort function for the software life-cycle. Also, Putnam presents constant effort rate in each phase. However, the size of total effort are variable according to the software projects under the influence of its size, complexity and operational environment. As a result, the allocated effort in each phase also differ from project to project. This paper suggests the criteria for effort allocation in planning, specifying, building, testing and implementing phase followed by the project total effort. These criteria are derived from 183 different projects. This result can be considered as a practical guideline in management of project schedule and effort allocation.

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A Case Report on Oro-Facial Manifestations in Leukemia (Oral Chronic GVHD) (백혈병 환자의 구강악안면 증상 발현에 관한 증례보고 (Oral Chronic GVHD))

  • Ahn, Hyoung-Joon;Kwon, Byung-Ki;Shin, Kyoung-Jin;Choi, Jong-Hoon;Kim, Chong-Youl
    • Journal of Oral Medicine and Pain
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    • v.25 no.2
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    • pp.159-165
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    • 2000
  • Subsequent to an allogenic stem cell transplantation(ASCT) on patients with hematologic malignancy(AML, ALL, CML, multiple myeloma, lymphoma etc.), chronic GVHD(graft versus host disease), which is an immunological reaction, occurs. With treatment results from patients who were diagnosed with ALL(acute lymphocytic leukemia), undergone BMT(bone marrow transplantation) and showed oral and skin lesions due to GVHD, treatment of oral manifestations of leukemia and its general management were studied. 90% of patients with chronic GVHD show change in the oral mucosa causing oral manifestations such as leukoplakia, lichenoid change of the oral mucosa, mucosal atrophy, erythema, ulceration and xerostomia. In treating GVHD, extensive systemic immunosuppression cause bacterial, viral, fungal infection that are fatal, and even if the treatment is successful, the patient is already in a severe immunosuppressed state. Therefore, localized target therapy is preferred. In another words, topical application(rinse, cream, ointment etc.) of cyclosporin and steroid in treating oral chronic GVHD is highly recommended, and the use of PUVA(Psoralen Ultraviolet A) and thalidomide is reported to be effective. In treating such diseases, dental treatment to control pain and prevent secondary infection of oral manifestations is very important. To those patients with systemic diseases who show limited effect by general dental treatment, non-invasive treatment such as the dental laser, in addition to the use of drugs, may be necessary to actively treat pain and help the healing process. For greater results, new effective methods are to be developed for treatment.

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Methanogenesis and Methane Oxidation in Paddy Fields under Organic Fertilization

  • Kim, Chungwoo;Walitang, Denver I.;Sa, Tongmin
    • Korean Journal of Environmental Agriculture
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    • v.40 no.4
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    • pp.295-312
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    • 2021
  • BACKGROUND: Global warming is one of the most pressing environmental issues which concomitantly complicates global climate change. Methane emission is a balance between methanogenesis and methane consumption, both of which are driven by microbial actions in different ecosystems producing methane, one of the major greenhouse gases. Paddy fields are major sources of anthropogenic methane emissions and could be compounded by organic fertilization. METHODS AND RESULTS: Literature reviews were conducted to give an overview of the global warming conditions and to present the relationship of carbon and methane to greenhouse gas emissions, and the need to understand the underlying processes of methane emission. A more extensive review was done from studies on methane emission in paddy fields under organic fertilization with greater emphasis on long term amendments. Changes in paddy soils due to organic fertilization include alterations of the physicochemical properties and changes in biological components. There are diverse phylogenetic groups of methanogens and methane oxidizing bacteria involved in methane emission. Also, multiple factors influence methanogenesis and methane oxidation in rice paddy fields under organic fertilization and they should be greatly considered when developing mitigating steps in methane emission in paddy fields especially under long term organic fertilization. CONCLUSION(S): This review showed that organic fertilization, particularly for long term management practices, influenced both physicochemical and biological components of the paddy fields which could ultimately affect methanogenesis, methane oxidation, and methane emission. Understanding interrelated factors affecting methane emission helps create ways to mitigate their impact on global warming and climate change.

Numerical Web Model for Quality Management of Concrete based on Compressive Strength (압축강도 기반의 콘크리트 품질관리를 위한 웹 전산모델 개발)

  • Lee, Goon-Jae;Kim, Hak-Young;Lee, Hye-Jin;Hwang, Seung-Hyeon;Yang, Keun-Hyeok
    • Journal of the Korea Institute of Building Construction
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    • v.21 no.3
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    • pp.195-202
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    • 2021
  • Concrete quality is mainly managed through the reliable prediction and control of compressive strength. Although related industries have established a relevant datasets based on the mixture proportions and compressive strength gain, whereas they have not been shared due to various reasons including technology leakage. Consequently, the costs and efforts for quality control have been wasted excessively. This study aimed to develop a web-based numerical model, which would present diverse optimal values including concrete strength prediction to the user, and to establish a sustainable database (DB) collection system by inducing the data entered by the user to be collected for the DB. The system handles the overall technology related to the concrete. Particularly, it predicts compressive strength at a mean accuracy of 89.2% by applying the artificial neural network method, modeled based on extensive DBs.

Study on key safety hazards and risk assessments for small section utility tunnel in urban areas (도심지 소단면 터널식 공동구의 핵심 안전 위험요소 및 위험성 평가 연구)

  • Seong, Joo-Hyun;Jung, Min-Hyung
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.20 no.6
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    • pp.931-946
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    • 2018
  • In line with the increased usability of utility pipe conduits in urban areas, construction and R&D activities of utility tunnel, incorporated with the shield TBM method, are actively under way. The utility tunnels are installed through underground excavation, and thus are relatively weak in terms of construction safety. However, hazards associated with the utility tunnel construction have not been properly identified, despite the introduction of a policy to the 'Design for Safety' for the purpose of reducing accident rates in the construction industry. Therefore, in this study, following the derivation of hazards associated with utility tunnel, these hazards were then used as the basis to uncover key safety hazards requiring extensive management in a field, which were then used to conduct a risk assessment having applied the matrix method so that the results can be utilized in risk assessment during the stages of utility tunnel planning, design, and construction, while also serving as a data reference.