• Title/Summary/Keyword: term functions

Search Result 792, Processing Time 0.022 seconds

A Study of the Diagnosis of Downtown Deterioration in Busan (부산시 도심 노후화 진단에 관한 연구)

  • Kwon, Il-Hwa;Nam, Kwang-Woo
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.16 no.4
    • /
    • pp.39-53
    • /
    • 2013
  • Although the efficient formation of urban space structure is a key factor in energy saving and environmentally-friendly aspect, the maintenance of the center and sub-center of the city that are key factors has been becoming increasingly difficult due to the variability and complexity of urban activities. In the case of Busan, amid the expansion of urban scale due to rapid economic development and overpopulation, systematic approaches to professional diagnosis and maintenance have been significantly insufficient - other than the city basic plan which has been conducted at an interval of 20 years. For the effective management of urban central area, systematic monitoring of the CBD through demand forecast and blight forecast at a city level must first be implemented. In order to fulfill this goal, this study is to figure out the current state of the CBD through the diagnosis on blight of the urban central area in the viewpoint of rehabilitation of the CBD and to propose the measures for practical utilization of the information about space for the further management of the central area of the city. For analysis, the study looks into the present state in terms of physical index, economic index, and social index. And then as a micro-approach by utilizing economic index, the study has thoroughly examined the economic blight of the Seomyun urban central area of Busan. The outcome of the analysis shows that in terms of population distribution and land utilization the area is in the stage of inefficient dispersion after having gone through the stage of suburbanization. It is expected that this study, as the material that proves the necessity of enhancing the function of the CBD, can propose the direction for the management of the urban center of Busan through blight prediction and management of the urban center and can provide the basic data for the long-term urban development that aims at the efficient strengthening of functions of the CBD.

Evaluation of Chloride Behavior and Service Life in Long-Term Aged FA Concrete through Probabilistic Analysis (장기재령 FA 콘크리트에 대한 염화물 거동 및 확률론적 염해 내구수명 평가)

  • Yoon, Yong-Sik;Kwon, Seung-Jun
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.8 no.3
    • /
    • pp.276-285
    • /
    • 2020
  • In this study, accelerated chloride diffusion tests were performed on OPC(Ordinary Portland Cement) and FA(Fly Ash) concrete considering three levels o f W/B(Water to Binder) ratio o n 1,095 curing days. The accelerated chloride diffusion coefficient and the passed charge were evaluated in accordance with Tang's method and ASTM C 1202, and the resistance performance to chloride attack improved over time. FA concrete showed excellent resistance performance against chloride penetration with help of pozzolanic reaction. As the result of the passed charge, FA concrete showed durability improvement, "low" grade to "very low" grade, but OPC concrete changed "moderate" grade to "low" grade at 1,095 curing days. After assuming the design variables used for durability design as normal distribution functions, the service life of each case was evaluated by the probabilistic analysis method based on MCS(Monte Carlo Simulation). In FA concrete, the increase of probability of durability failure was lower than that of OPC concrete with increasing time, because the time-dependent coefficient of FA concrete was up to 3.2 times higher than OPC concrete. In addition, the service life by probabilistic analysis was evaluated lower than the service life by deterministic analysis, since the target probability of durability failure was set to 10%. It is considered that more economical durability design will be possible if the mo re suitable target probability of durability failure is set for various structures through researches on actual conditions and indoor tests under various circumstances.

Development of GIS based Marine Mineral Resource Information System for Managing Marine Exploration Data (GIS 기반의 해양탐사자료 관리를 위한 해양광물자원정보시스템 설계 및 구축)

  • Kim, Dong-Il;Kim, Kye-Hyun;Park, Yong-Hyun
    • Spatial Information Research
    • /
    • v.19 no.6
    • /
    • pp.19-28
    • /
    • 2011
  • Recently, the interests of marine mineral resources has been increasing from the depletion of land resources around the world and many countries are involving in marine exploration work. South Korea is also currently performing exploration work to estimate the marine mineral resources around the Korean Peninsula. However, massive amounts of marine exploration data accumulated from the long-term exploration work have not been systematically managed. The data have been managed by the file based system instead of commercial database. The aim of this study is to construct GIS-based Marine Mineral Resource Information System using a spatial database for the core sediments of the marine exploration data. For constructing such DB system, GIS-based data items were classified, and a database was designed using relational database model. The database was constructed using commercial DBMS(Database Management System), Oracle. Also, necessary functions of the system were defined for the effective use of database based on users' requirement analysis. The GIS-based Marine Mineral Resource Information System has enabled to support the systematic management of the marine exploration data. Furthermore, it is expected that this spatial database will be useful in estimating the reserves of the mineral resources and provide valuable information for economic evaluation. In the future, the application of advanced techniques of spatial analysis and 3-dimensional display function will be required.

A potential user' Need of Utilization and Development Direction of Day Care Center (노인주간보호시설에 대한 잠재이용자의 이용욕구 및 발전방향)

  • Jeong, Ji-Na
    • Journal of Digital Convergence
    • /
    • v.18 no.4
    • /
    • pp.479-487
    • /
    • 2020
  • The purpose of this study is to identify a potential user's need for use and operational of the elderly day care center and to identify the problems and suggest development directions. The data collection was conducted on 320 ordinary people living in J-do through a questionnaire, and sought to understand the operational status of in-depth interview institutions for the heads and employees of six center. As a result of the analysis, a potential user's ware not aware of the functions and specific roles of day care center, the cost of facilities was covered by the government, and that facilities and the environment were important factors when using the center. In-depth interviews show that the current policy or system is far from reality and does not fit the status or role of the workers and the operational status of the agency, requiring the re-establishment of the on-site system. Based on the research results, the development direction of day care facilities requires active promotion and strengthening of family support for improving and enhancing awareness of day care facilities to citizens at the national level. Second, the quality of nursing services should be enhanced through improvements in facilities and the environment that reflect users' needs. Third, The government should improve the quality of nursing services by improving the poor employment conditions and treatment of workers to fit the reality.

Development of Statistical Downscaling Model Using Nonstationary Markov Chain (비정상성 Markov Chain Model을 이용한 통계학적 Downscaling 기법 개발)

  • Kwon, Hyun-Han;Kim, Byung-Sik
    • Journal of Korea Water Resources Association
    • /
    • v.42 no.3
    • /
    • pp.213-225
    • /
    • 2009
  • A stationary Markov chain model is a stochastic process with the Markov property. Having the Markov property means that, given the present state, future states are independent of the past states. The Markov chain model has been widely used for water resources design as a main tool. A main assumption of the stationary Markov model is that statistical properties remain the same for all times. Hence, the stationary Markov chain model basically can not consider the changes of mean or variance. In this regard, a primary objective of this study is to develop a model which is able to make use of exogenous variables. The regression based link functions are employed to dynamically update model parameters given the exogenous variables, and the model parameters are estimated by canonical correlation analysis. The proposed model is applied to daily rainfall series at Seoul station having 46 years data from 1961 to 2006. The model shows a capability to reproduce daily and seasonal characteristics simultaneously. Therefore, the proposed model can be used as a short or mid-term prediction tool if elaborate GCM forecasts are used as a predictor. Also, the nonstationary Markov chain model can be applied to climate change studies if GCM based climate change scenarios are provided as inputs.

Neuroprotective Effects of Herbal Ethanol Extract from Gynostemma pentaphyllum on Dopamine Neurons in Rotenone- and MPTP-induced Animal Model of Parkinson's Disease (Rotenone- 및 MPTP-유도 파킨슨병 동물 모델에서 돌외 에탄올 추출물의 Dopamine 신경세포 보호작용)

  • Suh, Kwang Hoon;Choi, Hyun Sook;Shin, Kun Seong;Zhao, Ting Ting;Kim, Seung Hwan;Hwang, Bang Yeon;Lee, Chong Kil;Lee, Myung Koo
    • YAKHAK HOEJI
    • /
    • v.57 no.2
    • /
    • pp.77-86
    • /
    • 2013
  • The neuroprotective effects of herbal ethanol extract (GP-EX) from Gynostemma pentaphyllum on dopamine neurons in animal model of Parkinson's disease (PD) were investigated. Rats and mice were administered with rotenone (2.5 mg/kg) for 28 days and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg) for 5 days for the PD models, respectively and the animals were simultaneously treated with GP-EX (30 mg/kg, daily). After preparing the PD models, the animals were also administered with L-DOPA (10 mg/kg) for 14 days with or without GP-EX treatment. Treatment with GP-EX (30 mg/kg) inhibited the rotenone- and MPTP-induced neurotoxic effects in dopamine neurons of rats or mice, which was determined by the numbers of tyrosine hydroxylase-immunohistochemical staining survival cells, as well as the levels of dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid. GP-EX (30 mg/kg) also showed the protective effects on neurotoxicity which was induced by long-term administration of L-DOPA (10 mg/kg) in rotenone- and MPTP-induced animal model of PD. The used doses of GP-EX (30 mg/kg) did not produce any signs of toxicity, such as weight loss, diarrhea, or vomiting, in rats and mice during the treatment periods. These results suggest that GP-EX has the protective functions against chronic L-DOPA-induced neurotoxic reactions in dopamine neurons of rotenone- and MPTP-induced animal model of PD. Therefore, the natural GP-EX may be beneficial in the prevention of PD progress and L-DOPA-induced neurotoxicity in PD patients.

Personal Name Authority Control in Korean Public Libraries (국내 공공도서관의 인명 전거제어의 현황 및 발전 방향)

  • Shim, Kyung
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.40 no.4
    • /
    • pp.221-244
    • /
    • 2006
  • This research analyzes the current status of personal name authority control and its impact on the end user searching against OPACs in public libraries in Korea. Further it also suggests the ways to improve the recall ratio in author search with a minimal modification, system-wise and authority-wise. on the KOLISNET as a stepping stone for other public libraries. Finally, a long-term plan for establishing proper authority work in public libraries including the National Library of Korea is briefly proposed. In order to find out whether authority works are conducted and examine how variant written forms of the same foreign name and variant names of the same person are treated, OPACS of the National Library of Korea, KOLISNET, and ten randomly selected public libraries were searched. Findings indicate that while the National Library of Korea was performing authority control, even incomplete, the rest did not appear to conduct any form or authority control. As a spinoff of the research, it is observed that in many public libraries their bibliographic records and retrieval methods are inaccurate, lacking consistency, and incomplete. In sum. it is strongly recommended that (1) as a start for authority work among public libraries personal name authority control should be conducted to enhance the identifying and collocating functions in OPACs, (2) a shared authority database, for which the National Library of Korea's authority database might be used. should be built for Public libraries.

Analysis on High School Students' Recognitions and Expressions of Changes in Concentration as a Rate of Change (변화율 관점에서 농도 변화에 대한 인식과 표현의 변화 과정에 대한 분석)

  • Lee, Dong Gun;Kim, Suk Hui;Ahn, Sang Jin;Shin, Jae Hong
    • Journal of Educational Research in Mathematics
    • /
    • v.26 no.3
    • /
    • pp.333-354
    • /
    • 2016
  • The aim of the present study is twofold. One is to confirm a hypothesis that a student's rate concept influences her conceiving change of a function in the view of rate of change and the other is to build up foundations for understanding the transition process from her rate concept to the concept of rate of change when she investigates the change of concentration as an intensive quantity. We explored how three participating high school students recognized and expressed change of given functions by using their rate concept as a conceptual tool. The result indicates that a change in students' rate concept might have an effect on understanding how function values change in term of rate of change. We also expect that it could be a catalyst for further research for clarifying the relationship between students' rate concept and their development of a concept of rate of change as a foundation for learning calculus.

Disaster Overall Prevention System for Beach Erosion and its Applications (해안침식 관리시스템과 그 적용)

  • Kim, Kyu-Han;Yoo, Hyung-Seok;Joung, Eui-Jin
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.20 no.6
    • /
    • pp.602-610
    • /
    • 2008
  • A beach has such functions as disaster prevention, providing an amenity place, attracting people and maintaining the coastal ecosystem. Already well known that a beach provides an amenity place, it has also been ascertained through various examples that a sand beach performs a very important function to maintain the coastal ecosystem as well. However, Beach erosion began to occur in Korea in the 1990's and posed a social problem in the late 1990's. Nowadays, along the shorelines of Korea's many beaches, about 400 beaches have reported erosion. This study demonstrate the Disaster Overall Prevention System for Beach Erosion and it's application. The Disaster Overall Prevention System for Beach Erosion is a coastal management system established for managing the implementation of long-term countermeasures to protect eroded beaches effectively in this study. Especially, the economic feasibility test and adaptive management for sustainable mitigation included in DOPS. The coastal prevention work applied to Namae beach is carried out by Disaster Overall Prevention System. Consequently, beach nourishment is proposed as a main countermeasure. Also, submerged artificial reefs and groin integrating artificial rock are proposed as secondary countermeasures for beach erosion. This resulted to be the optimal beach erosion countermeasure from DOPS, considering the economic and environmental conditions of the study area.

D-$\Pi$-A designed dye chromophores and nanoparticles: optical properties, chemosensor effects and PE/Aramid fiber colorations

  • Son, Young-A;Kim, Su-Ho;Kim, Young-Sung
    • Proceedings of the Korean Society of Dyers and Finishers Conference
    • /
    • 2010.03a
    • /
    • pp.40-40
    • /
    • 2010
  • Studies on attractive color changing property of dye chromophore and fluorophore have been greatly enjoyed in the related industrial and research fields such as optoelectronics, chemosensor, biosensor and so on. The optical property based on D-$\Pi$-A intramolecular charge transfer (ICT) system of chromophore molecules can be utilized as suitable sensing probes for checking media polarity and determining colorimetric chemosensing effect, especially heavy metal detection. These finding are obtained by absorption and emission properties. In this work, donor-acceptor D-$\Pi$-A type fluorescent dyes were designed and synthesized with the corresponding donor and acceptor groups. The selected donor moieties might be provided prominent amorphous properties which are very useful in designing and synthesizing functional polymers and in fabricating devices. Another reasons to choose are commercial availabilities in high purity and low price. Donor-bridge-acceptor (D-A) type dyes can produce impressive optical-physical properties, yielding them potentially suitable for applications in the synthesis of small functional organic molecules. Small organic functional molecules have unique advantages, such as better solubility, amorphous character, and represent an area of research which needs to be explored and developed. Currently, their applications in metalorganic compounds is rapidly expanding and becoming widespread in self-assembly processes, photoluminescence applications, chiral organocatalysts, and ingrafts with nanomaterials. Colloidal nanoparticles have received great attentions in recent years. The photophysical properties of nanoparticles, particularly in terms of brightness, photostability, emission color purity and broad adsorption range, are very attractive functions in many applications. To our knowledge background, colloidal nanoparticles have been enjoyed their applications in bio-probe research fields. This research interest can be raised by the advantages of the materials such as high photoluminescence quantum yields, sharp emission band, long-term photostability and broad excitation spectra. In recent, the uses of nanoparticles being embedded in a polymer matrix and binded on polymer surface have been explored and their properties such as photo-activation and strong photoluminescence have been proposed. The prepared chromophores and nanoparticles were investigated with absorption and emission properties, solvatochromic behaviors, pH induced color switching effects, chemosensing effects and HOMO/LUMO energy potentials with computer simulation. In addition, synthesized fluorophore dyes and particles were applied onto PE/Aramid fiber fluorescing colorations. And the related details were then discussed.

  • PDF