• Title/Summary/Keyword: Global State

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Learning the Covariance Dynamics of a Large-Scale Environment for Informative Path Planning of Unmanned Aerial Vehicle Sensors

  • Park, Soo-Ho;Choi, Han-Lim;Roy, Nicholas;How, Jonathan P.
    • International Journal of Aeronautical and Space Sciences
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    • v.11 no.4
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    • pp.326-337
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    • 2010
  • This work addresses problems regarding trajectory planning for unmanned aerial vehicle sensors. Such sensors are used for taking measurements of large nonlinear systems. The sensor investigations presented here entails methods for improving estimations and predictions of large nonlinear systems. Thoroughly understanding the global system state typically requires probabilistic state estimation. Thus, in order to meet this requirement, the goal is to find trajectories such that the measurements along each trajectory minimize the expected error of the predicted state of the system. The considerable nonlinearity of the dynamics governing these systems necessitates the use of computationally costly Monte-Carlo estimation techniques, which are needed to update the state distribution over time. This computational burden renders planning to be infeasible since the search process must calculate the covariance of the posterior state estimate for each candidate path. To resolve this challenge, this work proposes to replace the computationally intensive numerical prediction process with an approximate covariance dynamics model learned using a nonlinear time-series regression. The use of autoregressive time-series featuring a regularized least squares algorithm facilitates the learning of accurate and efficient parametric models. The learned covariance dynamics are demonstrated to outperform other approximation strategies, such as linearization and partial ensemble propagation, when used for trajectory optimization, in terms of accuracy and speed, with examples of simplified weather forecasting.

Computational Study of 3-Aminophenol·(CO2)1 Cluster: CO2 Capture Ability of 3-Aminophenol

  • Sohn, Woon-Yong;Kim, Min-Ho;Kim, Sang-Su;Kang, Hyuk
    • Bulletin of the Korean Chemical Society
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    • v.31 no.10
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    • pp.2806-2808
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    • 2010
  • The structure of 3-aminophenol $(CO_2)_1$ cluster was computationally studied both in the ground and the lowest singlet excited electronic states. The ground state structure and binding energy of the cluster was investigated using the second-order M$\ddoot{o}$ller-Plesset perturbation theory (MP2) at the complete basis set (CBS) limit. The excited state geometry of the cluster was obtained at the second-order approximate coupled cluster (CC2) level with cc-pVDZ basis set, and the $S_0-S_1$ absorption spectrum was simulated by calculating Franck-Condon overlap integral. The ground state geometry of the global minimum with a very high binding energy of 4.3 kcal/mol was found for the cluster, due to the interaction between amino group and $CO_2$ in addition to the strong $\pi-\pi$ interaction between the aromatic ring and $CO_2$. The excited state geometry shows a very big shift in the position of $CO_2$ compared to the ground state geometry, which results in low intensity and broad envelope in the Franck-Condon simulation.

A Study on the State Estimation for Distribution Substations (변전소 상태변수 추정에 관한 연구)

  • 이흥재;박성민;이경섭
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.3
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    • pp.103-109
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    • 2003
  • The validity of measured data is fundamental factor for the power system automation Measured values could have errors that are caused by the communication errors and malfunctioning measuring devices. The accuracy and reliability of measured values at a substation is an important condition for robust and fault tolerant automata. Errors can be reduced by state estimation, however, global reliability of state estimation goes down in case of the existence of some bad data In this paper, a least square state estimation and bad sensor detection algorithm based on chi-square theory, ale proposed and it is applied to a domestic 154kV distribution substations. A simulator together with user friendly graphic users interface is developed using C language and Visual Basic. TCP/IP is equipped for future connection with other operation systems.

Malaria Endemicity in the Rural Communities of Ebonyi State, Nigeria

  • Nwele, David Ekene;Onyali, Ikechukwu Oliver;Iwueze, Milliam Okwudili;Elom, Michael Okpara;Uguru, Ogbonna Elom Sabastian
    • Parasites, Hosts and Diseases
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    • v.60 no.3
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    • pp.173-179
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    • 2022
  • Malaria remains a global health threat. Approximately 97% of the population is at risk in sub-Saharan countries, particularly Nigeria. This study compared the performance of 2 diagnostic methods in assessing malaria endemicity in the rural communities of Ebonyi State, Nigeria. A total of 1,140 study participants were screened for malaria parasite using Rapid Diagnostic Test kits (RDT) in the field, while thick and thin films for microscopy were examined in the laboratory. Our result showed that malaria prevalence was 56.8 by RDT and 38.6% by microscopic test. Age group under 10 years had the highest prevalence of 28.9% (RDT) and 23.6% (microscopy), respectively. The highest prevalence of 19.5% by RDT was recorded in Onicha Local Government Area, while the highest prevalence of 13.4% with microscopy was recorded in Ezza North Local Government Area. The sensitivity and specificity of microscopic examination were both 100%, while those of RDT were 95.5% and 75.9%, respectively.

HMM with Global Path constraint in Viterbi Decoding for Insolated Word Recognition (전체 경로 제한 조건을 갖는 HMM을 이용한 단독음 인식)

  • Kim, Weon-Goo;Ahn, Dong-Soon;Youn, Dae-Hee
    • The Journal of the Acoustical Society of Korea
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    • v.13 no.1E
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    • pp.11-19
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    • 1994
  • Hidden Markov Models (HMM's) with explicit state duration density (HMM/SD) can represent the time-varying characteristics of speech signals more accurately. However, such an advantage is reduced in relatively smooth state duration densities or ling bounded duration. To solve this problem, we propose HMM's with global path constraint (HMM/GPC) where the transition between states occur only within prescribed time slots. HMM/GPC explicitly limits state durations and accurately describes the temproal structure of speech simply and efficiently. HMM's formed by combining HMM/GPC with HMM/SD are also presented (HMM/SD+GPC) and performances are compared. HMM/GPC can be implemented with slight modifications to the conventional Viterbi algorithm. HMM/GPC and HMM/SD_GPC not only show superior performance than the conventional HMM and HMM/SD but also require much less computation. In the speaket independent isolated word recognition experiments, the minimum recognition eror rate of HMM/GPC(1.6%) is 1.1% lower than the conventional HMM's and the required computation decreased about 57%.

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Foreign Direct Investments of Economic Infrastructure-Related Public Companies in Korea(1) : Theoretical Considerations, Trends and Strategies of Public Companies FDI (경제 하부구조 관련 공기업의 해외투자에 대한 연구(1) : 이론적 고찰, 공기업 FDI 특징 및 전략)

  • Kim, Yong-Chang
    • Journal of the Economic Geographical Society of Korea
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    • v.15 no.1
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    • pp.1-25
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    • 2012
  • This paper is the first paper of two linked papers about the FDI of the economic infrastructure-related public companies. This paper analyzes overseas investments of infrastructure public companies which is characterized by state control and support of socio-economic facilities and services. In theoretical consideration the genealogy and characteristics of FDI are examined, and then global FDI trends since 1970, institutional changes and FDI trends in Korea are analyzed. This analysis shows that the globalization of large state-owned enterprises or public companies from developing and transition economies constitutes an important component of FDI and new emerging source of FDI. Finally the objects and strategies of large 10 infrastructure public companies are analyzed in perspectives of features having both advanced and developing economies type.

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A Functional Matrix Approach to Pedagogical Enrichment of the Dispositional Core of Future Specialists' Experience of Social Interaction

  • Kovalenko, E.V.;Gubarenko, I.V.;Kovalenko, V.I.
    • International Journal of Computer Science & Network Security
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    • v.22 no.11
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    • pp.255-259
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    • 2022
  • The new social reality emerging amid the global rise of communication links and integration processes acutely emphasizes the problems of communication in large and small social systems. The method of their communication becomes one of the keys to ensuring global security. It has become the mission of humanitarian education to prepare the younger generations for life in a changing world with no image of the future and increasing uncertainty. In psychological and pedagogical research, there is a growing scientific interest in the problems of interaction of the individual with the social environment. The mental trace of a person's practice in society shapes the experience of social interaction, which constitutes simultaneously the source, tool, and condition for the emergence and development of personality. The study outlines the methodological foundations for the study of individual experiences of social interaction. A hypothesis about the productivity of the functional matrix method is tested. Materials for the training of specialists in the humanities include interdisciplinary approaches to the study and transformation of the experience of social interaction and systematic methodology for the study of complex objects. Fundamental to the study is the systematic-dialectical method, and the matrix method is employed as the instrumental-technological method. The paper presents the results of a multidisciplinary overview of scientific literature concerning the essential characteristics and functions of social interaction and the respective experience. The overview points to the fragmented nature of scientific understanding of the elements of experience outside its integrity and systemic properties. Based on the formula "personality interacts with the social environment", the study presents an algorithm for the application of a systematic methodology for the study of complex objects, which made it possible to identify the system parameters of experience at three levels of cognition and develop the reference structural and functional matrices for the didactic system of its pedagogical enrichment.

Awareness and Application of Internet of Things in Universities Libraries in Kwara State, Nigeria

  • Saliu Abdulfatai
    • International Journal of Knowledge Content Development & Technology
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    • v.14 no.4
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    • pp.65-84
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    • 2024
  • The study was conducted on the awareness and application of internet of things in universities libraries in Kwara State, Nigeria. the study formulated used four research questions and used eighty five (85) samples as the population using total enumerative sampling techniques. A survey method was used in undertaking the study, in which answers were sought on the level of awareness of the internet of things in universities libraries in Kwara State, the extent of application of the internet of things in universities libraries in Kwara State, the benefit of internet of things in universities libraries in Kwara State, the challenges faced in the application of internet of things in universities libraries in Kwara State. The data collected from the study were analyzed using frequency tables and percentage. The study discovered that there the students are aware of the internet of things in universities libraries in Kwara State and the benefit of internet of a things include: Device in the IoT platforms are heterogeneous and are based on different hardware platforms and networks, It gives the high level of interoperability and interconnectivity, IoT platform has sensors which detect or measure any changes in the environment to generate data that can report on their status or even interact with the environment, IoT comes with the combination of algorithms and computation, software & hardware that makes it smart and Anything can be interconnected with the global information and communication infrastructure and the study identified data interpretation problem, Lack of skilled and specialized workers, Cost and Challenges in online security as well as Software complexity are major challenges faced in the application of internet of things in universities libraries in Kwara State. In conclusion the study made some recommendations which include that: Future libraries should be equipped with new technologies and networking devices as soon as possible. As this will be essential for users and librarians to have sufficient knowledge about IOT technologies.

VARIABILITY OF THE LATENT HEAT FLUX DURING 1988-2005

  • Iwasaki, Shinsuke;Kubota, Masahisa
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.289-292
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    • 2008
  • Recently, several satellite data analyses projects and numerical weather prediction (NWP) reanalysis projects have produced the ocean surface Latent Heat Flux (LHF) data sets in the global coverage. Comparisons of these LHF data sets showed substantial discrepancies in the LHF values. Recently, the increase of LHF in during 1970s-1990s over the global ocean is shown by the LHF data that have been developed at the Objective Analyzed Air-Sea Fluxes (OAFlux) project. It is interesting to investigate the existence of the increase of LHF over a global ocean in the other LHF products. It is interesting to investigate the existence of the increase of LHF over a global ocean in the other LHF products. In this study, we assessed the consistencies and discrepancies of the inter-annual variability and decadal trend for the period 1988-2005 among six LHF products ((J-OFURO2, HOAPS3, IFREMER, NCEP1,2 and OAFlux) over the global ocean. As results, all LHF products showed a positive trend. In particular, the positive trend in satellite-based data analyses (J-OFURO2, HOAPS3, IFREMER) is larger than that in reanalysis products (NCEP1/2). Also, the consistencies and discrepancies are shown on the spatial patterns of the LHF trends across the six data sets. The positive trend of LHF is remarkable in the regions of western boundary currents such as the Kuroshio and the Gulf Stream in all LHF data sets. But, the discrepancies are shown on the spatial patterns of the LHF trends in tropics and subtropics. These discrepancies are primarily caused by the differences of the input meteorological state variables, particularly for the air specific humidity, used to calculate LHF.

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A Study on the Cases of the Application of 3D Apparel CAD System to the Domestic and Overseas Fashion Education (국내·외 패션교육에 있어서 3D 어패럴 CAD 시스템 활용 사례연구)

  • Lee, Min-Jeong;Sohn, Hee-Soon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.35 no.9
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    • pp.1112-1124
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    • 2011
  • The development of computer graphics and Internet technology has created a 3D Web-based virtual world that has transformed the global fashion industry environment. In this study, the application cases of 3D virtual fashion education were analyzed to discuss the necessity and application of a 3D apparel CAD curriculum as part of a special education for global fashion talent at Korean fashion-related colleges. Prior studies, literature, photo data and Internet data (in and out of Korea) were used for this study. The demonstration case studies were conducted for the virtual fashion education 'SLCC 2007' of Buffalo State College (U.S.), 'Ratava's Line (2004)' of SFU/FIT Collaborative Design Project (Canada and U.S.) and '2011 Graduation Fashion Show' of Ueda Fashion College (Japan). The results of the study show that the 3D apparel CAD system (as a core technology of the IT fashion industry) would allow the current mass production concept to change to a new paradigm of 'mass customization' along with new fashion business types that include global fashion companies and Web-based Internet, mobile and virtual-world shopping malls. In addition, it appears that the system should be included in the curriculum of fashion-related colleges and institutes to educate technical designers for the global fashion industry and global fashion talent with comprehensive system operation and management ability, and to promote single proprietor companies.