• Title/Summary/Keyword: the urban environment

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A Realistic Path Loss Model for Real-time Communication in the Urban Grid Environment for Vehicular Ad hoc Networks

  • Mostajeran, Ehsan;Noor, Rafidah Md;Anisi, Mohammad Hossein;Ahmedy, Ismail;Khan, Fawad Ali
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.10
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    • pp.4698-4716
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    • 2017
  • Wireless signal transmission is influenced by environmental effects. These effects have also been challenging for Vehicular Ad hoc Network (VANET) in real-time communication. More specifically, in an urban environment, with high mobility among vehicles, a vehicle's status from the transmitter can instantly trigger from line of sight to non-line of sight, which may cause loss of real-time communication. In order to overcome this, a deterministic signal propagation model is required, which has less complexity and more feasibility of implementation. Hence, we propose a realistic path loss model which adopts ray tracing technique for VANET in a grid urban environment with less computational complexity. To evaluate the model, it is applied to a vehicular simulation scenario. The results obtained are compared with different path loss models in the same scenario based on path loss value and application layer performance analysis. The proposed path loss model provides higher loss value in dB compared to other models. Nevertheless, the performance of vehicle-vehicle communication, which is evaluated by the packet delivery ratio with different vehicle transmitter density verifies improvement in real-time vehicle-vehicle communication. In conclusion, we present a realistic path loss model that improves vehicle-vehicle wireless real-time communication in the grid urban environment.

Propagation Path Analysis for Planning a Cell in the CDMA Mobile Communication

  • Park, Jung-Jin;Kim, Seon-Mi;Choi, Dong-You;Ryu, Kwang-Jin;Choi, Dong-Woo;Noh, Sun-Kuk;Park, Chang-Kyun
    • Proceedings of the IEEK Conference
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    • 2002.07b
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    • pp.1078-1081
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    • 2002
  • In microcell or picocell mobile communication using cellular method, we suggested propagation prediction model which can accurately and rapidly interpret mobile communication propagation environment in urban, when subscriber service is done based on the main road in urban. Further, we simulated suggested propagation prediction model under the hypothesis of urban propagation environment of PCS mobile communication, analyzed receiving field strength by area within a cell, and finally suggested the optimal transmitting power and location condition of microcell or picocell mobile communication base station

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An Analysis of the Environment-Friendly Envelop Show in European Urban Housing (유럽의 집합주택에서 나타나는 환경친화적인 외피구성기법 분석)

  • Lee, Chung-Mi;Oh, Se-Gyu
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2005.11a
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    • pp.279-282
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    • 2005
  • As cognizance of necessity of environmentally friendly building is growing, techniques to construct environmentally friendly envelope of contemporary architecture is being changed and developed. Though the stream of times likes this, applications of those are focused on office buildings but rarely on residential projects. A begin of this study is to address analysis of environmentally friendly envelope techniques in urban housing in Europe constructed after 1995 which is the very time that the notion of ecological architecture. The result of this analysis should be a suggestion of radical data to make buildings be more buildings be more environmentally friendly and having amenities.

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Development of an Eco-Value Engineering Support System

  • Sun-Im Kang;Jong-Hyeob Kim;Mi-A Jung;Chang-Taek Hyun;Sangwon Han
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.115-121
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    • 2013
  • A number of urban renewal projects are currently being implemented around the world. Current project management tools are limited in effectively dealing with numerous issues regarding management of these projects (e.g., simultaneous execution of multiple projects). As an effort to address this deficiency, an Intelligent Program Management Information System (i-PgMIS) was developed for effective management of urban renewal projects. The i-PgMIS is a web-based system consisting of various modules including cost management, schedule management, risk management, change management, eco-value engineering (EVE) and so on. Based on the recognition of increasing awareness of creating sustainable built environment, this paper focuses on the EVE module that can support eco-value analysis at program-level management. The EVE module is expected to enhance value and sustainability of construction processes throughout the whole 'program' lifecycle and further to support program feasibility study based on life cycle costing.

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Characteristics of major offensive odorants emitted from urban stormwater catch basins (도심 하수관거에서 발생하는 주요 지정악취물질들의 배출특성)

  • Hong, One-Feel;Kabir, Ehsanul;Susaya, Janice;Kim, Ki-Hyun
    • Analytical Science and Technology
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    • v.23 no.4
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    • pp.347-356
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    • 2010
  • Emission characteristics of major offensive odorants were investigated using odor samples collected from two urban stormwater catch basins with highly contrasting environmental conditions. A total of 6 major offensive odorants ($H_2S$, $CH_3SH$, DMS, DMDS, $CH_3CHO$ (AA), and $NH_3$) were measured. For this comparative analysis, odor intensity (OI) of all odorants was derived from their concentration data via empirical equations introduced by Nagata. Both the absolute magnitude of odorant concentrations and their OI values were used concurrently to evaluate the occurrence pattern of each individual odorant. According to our analysis, RSCs including $CH_3SH$, $H_2S$, and DMS tend to exhibit the highest odor strengths among all 6 compounds investigated. The overall results of our study suggest that the emissions of major offensive odorants from urban stormwater catch brains can be explained at least partially by the temporal trend of human activity.

Urban Heat Islands in Seoul during the Summertime of 2003 (2003년 여름철 서울의 도시열섬)

  • Kim Yeon-Hui;Eom Hyang-Hui;O Seong-Nam;Kim Sang-Baek
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.503-503
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    • 2003
  • Urban heat islands related with Cheongyecheon restoration in Seoul metropolitan area for the summertime of 2003. To investigate the spatial and temporal structure of the urban heat island in Seoul, temperature data measured at 32 automatic weather stations (AWSs) in the Seoul metropolitan area and 12 additional stations operated by the portable device for the measurement of temperature and relative humidity in the Cheonggyecheon area. (omitted)

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A STUDY ON DEVELOPING DECISION SUPPORT MODULES OF iPMIS(INTELLIGENT PROGRAM MANAGEMEN INFORMATION SYSTEM) FROM ONTOLOGICAL PERSPECTIVE

  • Jae-Bok Lim;Ju-Hyung Kim;Jae-Jun Kim
    • International conference on construction engineering and project management
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    • 2009.05a
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    • pp.717-724
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    • 2009
  • Most recent programs in and out of the country are related to urban renewal projects. Contemporary project management information systems have been developed was to manage single or multiple projects focusing on their construction phase, and those have limitations to apply to large-scale complicated mega projects. So, this study explain the core concept of decision support modules for iPMIS (Intelligent Program Management Information System) and its major functions to support project owner and participants by introducing ontology in the web environment. This study confined the scope of research to the planning phase of urban environment improvement projects. Ontological logic structure and relation about planning works is essential parts and three functions to implement decision support module are developed.

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Study on Exterior Color of Apartments in Seoul for the Color Environment (색채 환경을 고려한 서울시 아파트 외관 색채 계획에 관한 연구)

  • Yi, Young-Ran;Chu, Beom
    • Korean Institute of Interior Design Journal
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    • v.25 no.2
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    • pp.143-150
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    • 2016
  • Color plan that contains corporate color of Seoul apartment has a great influence on city environment, considering high-rise vertical dispersion and extent. Therefore, it is necessary to view color plan from an integrative viewpoint. Here, this research aimed at deriving guideline factors of esthetic color plan based on city identity, by recognizing the importance of apartment color and color plan characteristic of recently built brand apartments. Exterior color plan characteristic of Seoul brand apartments seen in this research, first, most of dominance colors were in same color similar tone with warm color in bright and warm image, as the psychological function, accessory colors appeared in similar tone of similar color harmonious with the dominance color. Also, accent color was highlighted with its identity through cooperative color. Second, emotional effect diminished size and weight of high-rise apartment. The upper levels showed clear and clean image, middle to lower level showed stability and comfortable image, on the whole, refined and urbane image that aim for natural and modern image. Therefore, apartment color plan requires, first, in respect of dominance color, unity is required proper for urban image by preparing color permission limitation standard. Second, dominance color and accessory color require historicity and differentiation in sociality that urban identity gets. Third, high-rise upper level cooperative color accent color requires compatibility with urban landscape. Lastly, guideline along with rate is required for color, tone, and pattern, etc. by extent contrast. Here, apartment color plan requires consistent research as urban environment color, also, base study should be accelerated as a part of competitive city branding.

Service Delivery in Urban Local Authorities: A Literature Review Paper

  • Alice MOTSI;Samuel GUMBE;Noel MUZONDO;Forbes MAKUDZA
    • The Journal of Industrial Distribution & Business
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    • v.14 no.10
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    • pp.23-33
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    • 2023
  • Purpose: This paper provides a literature review of both qualitative and quantitative research on service delivery in urban local authorities as portrayed in literature and offers more insight into the concept thereby developing and facilitating an improved understanding of service delivery and proffering strategies for improving service delivery in urban local authorities. Research design, data and methodology: The study adopted a desktop research methodology. Empirical and theoretical research and articles which are relevant to service delivery in urban local authorities are reviewed and analysed. Only secondary information gathered through those articles and research is used to analyse and build literature review on service delivery in urban local authorities. Results: a literature review of both qualitative and quantitative research on service delivery in urban local authorities as portrayed in literature proffering strategies for improving service delivery in urban local authorities. Conclusions: It is evident that service delivery is an area which needs more attention, especially in developing countries. The service delivery environment is also changing rapidly, calling for strategies to match such changes. This paper facilitates an improved understanding of service delivery, proffering strategies for improving service delivery in urban local authorities. These strategies are essential in improving service delivery challenges.

Urban Stormwater Capture Curve using 3-Parameter Mixed Exponential Probability Density Function (3변수 혼합 지수 확률밀도함수를 이용한 도시 강우 유출수 포착곡선의 작성)

  • Han, Suhee;Park, Moo Jong;Kim, Sangdan
    • Journal of Korean Society on Water Environment
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    • v.24 no.4
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    • pp.430-435
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    • 2008
  • In order to design Non-point source management, the aspect of statistical features of the entire precipitation data should be focused since non-point source discharge is driven by continuous rainfall runoffs. 3-parameter mixed exponential probability density function is used to establish urban stormwater capture curve instead of previous single-parameter exponential PDF. Then, recent 10-year data in Busan are applied to establish the curve. The result shows that 3-parameter mixed PDF gives better resolution.