• Title/Summary/Keyword: sources of complexity

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Air Pollution Monitoring in Taiwan: An Application of Tethersonding in Coastal Central Taiwan

  • Cheng Wan-Li;Hsu C. H.;Huang J. D.;Shi J. L.
    • Journal of Environmental Health Sciences
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    • v.31 no.3
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    • pp.215-220
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    • 2005
  • The atmospheric transportation and dispersion processes of air pollutants are important issues in dealing with air pollution problems. Air pollutants originated from biological and anthropogenic activities are not only limited to the local emission sources, but could also be transported and dispersed to other regions by synoptic weather systems. Besides, the complexity of topography of central Taiwan helps accumulating air pollutants to promote high-concentration episodes. The techniques of tethersonding were applied to monitor the vertical profiles of winds, air temperatures and humidity, as well as to collect air samples, to be analyzed for pollutants $(O_3,\;NO_2,\;NO\;and\; NMHC)$ from the ground up to 1000m. A time period of about one week, 19-26 October 2002, was chosen as the sampling period due to the high frequency of episode occurrence in autumn based on the past records. Associating with the analysis of weather patterns, the atmospheric characteristics over high-concentration areas can be resolved in more detail. The result of the tethersonding studies showed that weak northerly sea breeze (with thickness about 300m) with low wind speed (about 1 to 2 m/sec) could help develop high ozone concentrations in the down-wind areas. It is also important to have a built-up aloft of precursors and ozone to develop high concentration on the previous day.

Air Pollution Monitoring in Taiwan: An Application of Tethersonding in Coastal Central Taiwan

  • Cheng, Wan-Li
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2005.06a
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    • pp.184-210
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    • 2005
  • The atmospheric transportation and dispersion processes of air pollutants are important issues in dealing with air pollution problems. Air pollutants originated from biological and anthropogenic activities are not only limited to the local emission sources, but could also be transported and dispersed to other regions by synoptic weather systems. Besides, the complexity of topography of central Taiwan helps accumulating air pollutants to promote high-concentration episodes. The techniques of tethersonding were applied to monitor the vertical profiles of winds, air temperatures and humidity, as well as to collect air samples, to be analyzed for pollutants ($O_3,\;NO_2$, NO and NMHC) from the ground up to 1000 m. A time period of about one week, 19 -26 October 2002, was chosen as the sampling period due to the high frequency of episode occurrence in autumn based on the past records. Associating with the analysis of weather patterns, the atmospheric characteristics over high-concentration areas can be resolved in more detail. The result of the tethersonding studies showed that weak northerly sea breeze (with thickness about 300 m) with now wind speed (about 1 to 2 m/sec) could help develop high ozone concentrations in the down-wind areas. It is also important to have a built-up aloft of precursors and ozone to develop high concentration on the previous day.

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A Study on the Identification of Cutting-Edge ICT-Based Converging Technologies

  • Kim, Pang Ryong;Hwang, Sung Hyun
    • ETRI Journal
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    • v.34 no.4
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    • pp.602-612
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    • 2012
  • It is becoming increasingly difficult to identify promising technologies due to the influx of new technologies and the high level of complexity involved in many of these technologies. Identifying promising information and communications technology (ICT)-based converging technologies holds the key to finding new sources of economic growth and forward momentum. The goal of this study is to identify cutting-edge ICT-based converging technologies by examining the latest trends in the US patent market. Analyzing the US patent market, the most competitive of such markets in the world, can yield certain clues about which of the ICT-based converging technologies may be the next revolutionary technologies. For a classification of these technologies, this study follows the International Patent Classification system. As for ICT, there are 58 related fields at the subclass level and 831 fields at the main-group level. For emerging and converging technologies, there are 75 at the main-group level. From these technologies, a final selection for cutting-edge ICT-based converging technologies is made using a composite index reflecting the converging coefficient, emerging coefficient, and technology impact index.

Multi-objective path planning for mobile robot in nuclear accident environment based on improved ant colony optimization with modified A*

  • De Zhang;Run Luo;Ye-bo Yin;Shu-liang Zou
    • Nuclear Engineering and Technology
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    • v.55 no.5
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    • pp.1838-1854
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    • 2023
  • This paper presents a hybrid algorithm to solve the multi-objective path planning (MOPP) problem for mobile robots in a static nuclear accident environment. The proposed algorithm mimics a real nuclear accident site by modeling the environment with a two-layer cost grid map based on geometric modeling and Monte Carlo calculations. The proposed algorithm consists of two steps. The first step optimizes a path by the hybridization of improved ant colony optimization algorithm-modified A* (IACO-A*) that minimizes path length, cumulative radiation dose and energy consumption. The second module is the high radiation dose rate avoidance strategy integrated with the IACO-A* algorithm, which will work when the mobile robots sense the lethal radiation dose rate, avoiding radioactive sources with high dose levels. Simulations have been performed under environments of different complexity to evaluate the efficiency of the proposed algorithm, and the results show that IACO-A* has better path quality than ACO and IACO. In addition, a study comparing the proposed IACO-A* algorithm and recent path planning (PP) methods in three scenarios has been performed. The simulation results show that the proposed IACO-A* IACO-A* algorithm is obviously superior in terms of stability and minimization the total cost of MOPP.

Multimodal Medical Image Fusion Based on Sugeno's Intuitionistic Fuzzy Sets

  • Tirupal, Talari;Mohan, Bhuma Chandra;Kumar, Samayamantula Srinivas
    • ETRI Journal
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    • v.39 no.2
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    • pp.173-180
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    • 2017
  • Multimodal medical image fusion is the process of retrieving valuable information from medical images. The primary goal of medical image fusion is to combine several images obtained from various sources into a distinct image suitable for improved diagnosis. Complexity in medical images is higher, and many soft computing methods are applied by researchers to process them. Intuitionistic fuzzy sets are more appropriate for medical images because the images have many uncertainties. In this paper, a new method, based on Sugeno's intuitionistic fuzzy set (SIFS), is proposed. First, medical images are converted into Sugeno's intuitionistic fuzzy image (SIFI). An exponential intuitionistic fuzzy entropy calculates the optimum values of membership, non-membership, and hesitation degree functions. Then, the two SIFIs are disintegrated into image blocks for calculating the count of blackness and whiteness of the blocks. Finally, the fused image is rebuilt from the recombination of SIFI image blocks. The efficiency of the use of SIFS in multimodal medical image fusion is demonstrated on several pairs of images and the results are compared with existing studies in recent literature.

The Realtime method of 3D Sound Rendering for Virtual Reality : Complexity Reduction of Scene and Sound Sources (장면 및 음원 복잡도 축소에 의한 3차원 사운드 재현의 실시간화 기법)

  • Seong SukJeong;Yi JeongSeon;Oh SuJin;Nam YangHee
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.07b
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    • pp.550-552
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    • 2005
  • 실감 재현이 중요한 가상현실 응용에서는 사용자에게 고급 그래픽 환경을 제시하고 사용자의 인터랙션에 즉각적인 피드백을 제공함으로서 실재감과 몰입감을 증대시키는 연구가 진행되어왔다. 실재감, 공간감 전달을 위해 시각과 청각을 함께 활용하는 것이 효과적이나, 가상공간의 특징을 반영한 3차원 사운도 재현 연구는 국내외 통틀어 초기단계에 머물러 있다. 실재감과 공간감을 반영한 3차원 사운드의 재현을 위해서는 음원의 전파, 반사, 잔향 풍의 계산이 사용자의 인터랙션에 따라 새롭게 계산되어야한다. 그러나 사운드 전파경로와 공간을 이루는 모든 폴리곤들과의 충돌을 검사하며 반사 등을 계산하는 것은 실시간성이 중요한 가상현실응용에서는 무리가 따르므로 실 시간성을 보장하기 위한 계산량 축소가 요구된다. 본 논문에서는 다수의 음원이 존재하는 복잡한 가상공간에서의 3차원 사운드를 재현하기 위하여 사운드 신과 계산에 필요한 최소한의 정보를 가지는 오디오 씬 그라프의 공간을 재구성하고 다수의 음원을 대상으로 음원 축소 및 군집화를 적용하여 3차원 사운드효과를 실시간으로 재현하는 알고리즘을 제안한다.

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A Study of Research Publication Ethics for Social Science Researcher

  • Eungoo KANG;Hee-Joong HWANG
    • Journal of Research and Publication Ethics
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    • v.4 no.2
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    • pp.19-25
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    • 2023
  • Purpose: This research article aim is to critically examine the ethical principles that govern research publication in social sciences and to identify and analyze the everyday ethical challenges social science researchers face during the publication process. Also, the research explores the factors contributing to ethical violations in social science research publication. Research design, data, and methodology: The present research has conducted comprehensive literature analysis and the authors of this research has figured out total 24 significant prior studies in the current literature dataset for the literature review and finding section. The procedure of data obtaining included the elimination process to screen dissertation papers, conference papers, and internet sources. Results: Previous The sociologies, given their emphasis on the human way of behaving and interactions, demand heightened ethical considerations due to the potential impact of research findings on individuals and society. Therefore, understanding and upholding ethical standards are essential for researchers at all career stages. Conclusions: In order to retain the integrity, legitimacy, and societal influence of research findings, ethical issues are crucial and the necessity for flexible and comprehensive ethical frameworks is highlighted by the rapid evolution of research methodology, digital platforms, and interdisciplinary collaborations, adding new dimensions of ethical complexity.

Packet scheduling algorithm for guaranteed bound and firewall property of delay performance (지연의 상한 보장과 안정성을 고려한 패킷 스케쥴링 알고리즘)

  • 정대인
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.5C
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    • pp.435-444
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    • 2002
  • In this paper, a novel packet scheduling algorithm, so-called the CSL algorithm is discussed, whereby the firewall property as well as the deterministic delay bound guarantee are supported in session level. Lots of simulation studies validate those properties of the CSL algorithm. The CSL algorithm is distingushable from the well- known EDD scheme in terms of the firewall property. Regarding the implementation complexity, the CSL algorithm turns out to be of 0(1) besides the sorting overhead. Owing to the maintained generic fair queueing structure in the CSL algorithm, a various fair queueing schemes can be applied with minor modification. For the TCP/IP network which is vulnerable to the misbehaving traffic sources, the firewall property of the CSL algorithm is quite useful for the advanced quality of services.

Epicardial Microwave Ablation of Atrial Fibrillation (심방세동치료에 적용된 심외막극초단파차단술 -1예 보고-)

  • 박정식;이정환;안영찬;황여주;이재익;현성렬;전양빈;이창하;박철현
    • Journal of Chest Surgery
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    • v.37 no.7
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    • pp.609-612
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    • 2004
  • Even though the Cox-Maze III procedure is the gold standard in the therapy for atrial fibrillation (AF) and its outcome is excellent, the complexity of the operation, longer cardiopulmonary bypass time and the risk of bleeding have tended to dissuade cardiac surgeons from its application. The recent data of the pathogenesis of AF and the development of alternative energy sources have facilitated the development of the modified Cox-Maze procedure rapidly. We reported that atrial fibrillation was conversed to sinus rhythm by the epicardial microwave ablation without cardiopulmonary bypass and the normal sinus rhythm was observed during 33 months of follow-up period.

Physicochemical and Toxicological Properties of Effluent Organic Matters from Sewage and Industrial Treatment Plants (하폐수처리장 유래 방류수유기물질의 물리화학적 및 독성학적 특성)

  • Yoo, Jisu;Lee, Bomi;Hur, Jin;Jung, Jinho
    • Journal of Korean Society on Water Environment
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    • v.30 no.1
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    • pp.80-86
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    • 2014
  • Unlike to natural organic matters (NOMs), effluent organic matters (EfOMs) are not well understood due to their complexity and heterogeneity. In this study, EfOMs from sewage and industrial wastewater treatment effluents and Suwannee River NOM (SRNOM) were isolated into hydrophobic (HPO), transphilic (TPI) and hydrophilic (HPI) fractions. Specific ultraviolet absorbance (SUVA) and fluorescence excitation emission matrix (FEEM) analyses were used to characterize physicochemical properties. In addition, acute toxicity and oxidative stress to Daphnia magna were evaluated to characterize toxicological properties. EfOMs showed similar properties to microbially derived organic matters having low hydrophobicity, which are totally different from SRNOM having high hydrophobicity. Moreover, acute toxicity and antioxidant enzyme activity in D. magna was largely dependent on fraction types of EfOMs. These findings suggest that EfOMs have different physicochemical and toxicological properties compared with those of NOMs, which needs to be further identified with various sources of EfOMs.