• Title/Summary/Keyword: Extension of Environments

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Reliability Analysis for Stress Corrosion Cracking of Suspension Bridge Wires (현수교케이블의 응력부식에 관한 신뢰성해석)

  • Taejun;Andrzej S. Nowak
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2003.04a
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    • pp.537-544
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    • 2003
  • This paper deals with stress corrosion cracking behavior of high strength steel exposed to marine environments. The objective is to determine the time to failure as a function of hydrogen concentration and tensile stress in the wires. A crack growth curve is modeled using finite element method (FEM) program. The coupled hydrogen diffusion-stress analyses of SCC were programmed separately. The first part is calculating stress and stress intensity /sup 1)/factor of a cylindrical shell, prestressing tendon or suspension bridge wires, from the initiation of cracks to rupture. Virtual crack extension method, contour integral method, and crack tip elements are used for the calculation of stresses in front of the crack tip. Comparisons of the result show a good agreement with the analytical equations and wire tests. The second part of the study deals with the programming of hydrogen diffusion, affected by hydrostatic stress, calculated at the location of boundary of plastic area around the crack tip. The results of paper can be used in the design and management of prestressed structures, cable stayed and suspension bridges. Time dependent correlated parallel reliabilities of a cable, composed of 36 wires, were evaluated by the consideration of the deterioration of stress corrosion cracking.

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Process-Aware Internet of Things: A Conceptual Extension of the Internet of Things Framework and Architecture

  • Kim, Meesun;Ahn, Hyun;Kim, Kwanghoon Pio
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.8
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    • pp.4008-4022
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    • 2016
  • This paper tries to extend the conventional conceptual framework of the Internet of Things (IoT) so as to reify an advanced pervasive IoT-community collaboration concept, which is called the process-aware Internet of Things. The extended conceptual framework is embodied as a referential architecture that can be a standardized reference model supporting the conceptual integration of the Internet of Things and the process awareness. The extended referential architecture covers the full range of the architectural details from abstracting the process-aware behavioral semantics to reifying the IoT-process enactments. These extended framework and architecture ought to be the theoretical basis for implementing a process-aware IoT-community computing system supporting process-aware collaborations of Things in pervasive computing environments. In particular, we do point up that the proposed framework of the process-aware Internet of Things is revised from the Internet of Things framework announced in ITU-T SG133 Y.2060 [26] by integrating the novel concept of process awareness. We strongly believe that the extended conceptual framework and its referential architecture are able to deliver the novel and meaningful insight as a standardized platform for describing and achieving the goals of IoT-communities and societies.

An Analysis of Middle School Teachers' Teaching Profession Consciousness and Job Satisfaction by Level of their Professional Socialization (중학교 교사의 교직사회화 단계별 교직의식 및 직무만족도 분석)

  • WON, Hyo-Heon;NAM, In-Ae
    • Journal of Fisheries and Marine Sciences Education
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    • v.15 no.2
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    • pp.145-153
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    • 2003
  • The purpose of this study is to help improvements of education and effective management of school organization by grasping interrelationship between middle school teachers' job satisfaction and their teaching profession consciousness based on the different levels of professional socialization. To accomplish the purpose stated above, two questions were selected. First, how different are the middle school teachers' teaching profession consciousness according to the different levels of professional socialization? Second, how different are the middle school teachers' job satisfactions according to the levels of professional socialization. To answer these questions, a theoretical investigation into previous studies was made, and survey method was adopted for the inquiry. 500 questionnaires were given to teachers of 14 middle schools in Busan Metropolitan City, 470 questionnaires were collected. The results of the analysis may be summarized as follows: First, the teaching profession consciousness of middle school teachers show high level. Especially, there are much difference of teaching profession consciousness between the period of adaptation and maturity. Second, job satisfaction of middle school teachers show low level, and the job satisfaction points of compensations, school administrations, changes of educational environments are lower than the points of human relations, extension of profession, stress of duties. Especially, there are much difference between the period of adaptation and growth, adaptation and maturity, growth and maturity, growth and mellowness.

Predicting the spray uniformity of pest control drone using multi-layer perceptron (다층신경망을 이용한 드론 방제의 살포 균일도 예측)

  • Baek-gyeom Seong;Seung-woo Kang;Soo-hyun Cho;Xiongzhe Han;Seung-hwa Yu;Chun-gu Lee;Yeongho Kang;Dae-hyun Lee
    • Journal of Drive and Control
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    • v.20 no.3
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    • pp.25-34
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    • 2023
  • In this study, we conducted a research on optimizing the spraying performance of agricultural drones and predicted the spraying performance in various flight conditions using the multi-layer perceptron (MLP). Data was collected using a test device for pesticide spraying performance according to the water sensitive paper (WSP) evaluation. MLP training involved supervised learning to achieve a coefficient of variation (CV), which indicates the degree of uniform spraying. The performance evaluation was conducted using R-squared (R2), the test samples showed an R2 of 0.80. The results of this study showed that drone spraying performance can be predicted under various flight environments. In addition, the correlation analysis between flight conditions and predicted spraying performance will be useful for further research on optimizing the spraying performance of agricultural drones.

A Framework for Developing interoperable Knowledge Discovery System

  • Li, Sheng-Tun;Shue, Li-Yen
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2001.01a
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    • pp.435-440
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    • 2001
  • The development of web-aware knowledge discovery system has received a great deal of attention in recent years. It plays a key-enabling role for competitive businesses in the E-commerce era. One of the challenges in developing web-aware knowledge discovery systems is to integrate and coordinate and coordinate existing standalone or legacy knowledge discovery applications in a seamless manner, so that cost-effective systems can be developed without the need of costly proprietary products. In this paper, we present an approach for developing a framework of web-aware interoperable knowledge discovery system to achieve this purpose. This approach applies RMI and high-level code wrapper of Java distributed object computing to address the issues of interoperability in heterogeneous environments, which includes programming language, platform, and visual object model. The effectiveness of the proposed framework is demonstrated through the integration and extension of the two well-known standalone knowledge discovery tools, SOM_PAK and Nenet. It confirms that a variety of interoperable knowledge discovery systems can be constructed efficiently on the basis of the framework to meet various requirements of knowledge discovery tasks.

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A Strategy of the Environmental Color of the Frontage Zone of Sidewalk for the Walkability (워커빌리티를 위한 가로변 전면공간의 환경색채 전략)

  • Kim, Sun-Young
    • Korean Institute of Interior Design Journal
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    • v.27 no.1
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    • pp.12-20
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    • 2018
  • After the "Landscaping Law" was enacted in 2007 Korea, national and local governments has been responding swiftly by seeking various methods. Seoul Metropolitan City and other municipalities have established "Seoul Coloring and Systematization" project, which analyzes and extracts the humanities, humanities and natural environments in 2007 as an opportunity to recognize the importance of environmental color. However, it is necessary to slightly supplement the color scheme created by the observer's concept. In this way, you have to find the color of the environment in a city where real life takes place. The city's environmental color has the concept of "walking" as the basic human behavior. Because the average speed is 4km, it differs from that of a vehicle that travels more than 60km per hour. Also, most of the frontage zone is used except for special cases. Therefore the characteristics of the environmental color and frontage zone on the road side were concluded in this paper as Single Type, Connection Type, and Extension Type. In addition, the principle of environmental color of city was established by the change of texture according to space of time and the characteristics of urban scale, and new media characteristics were found in various interactions. The results of this study suggest an environmental coloring strategy for workability such as hue continuity, hue harmonization and integrated design.

An intelligent cruise control system using a self-tuning fuzzy algorithm (자기조절 퍼지 알고리듬을 이용한 지능순항제어시스템 개발)

  • Jung, Seung-Hyun;Lee, Gu-Do;Kim, Sang-Woo;Park, Poo-Gyeon
    • Journal of Institute of Control, Robotics and Systems
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    • v.4 no.1
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    • pp.68-75
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    • 1998
  • The Intelligent Cruise Control system, ICC, is a driver assisting system for controlling relative speed and distance between two vehicles in the same lane. The ICC may be considered as an extension of a traditional cruise control, not only keeping a fixed speed of the vehicle, but correcting the speed also to that of a slower one ahead. This paper presents a real-time self-tuning fuzzy control algorithm to develop ICC. The self-tuning fuzzy control law is adopted to reduce the effects of nonlinearities of the vehicle and various road environments. In the self-tuning algorithm an interior penalty method is applied to preserve the inherent order of membership functions and is modified as an on-line algorithm for real time application. Via simulations, the performance of the suggested control algorithm is compared with a PID and a fuzzy control without self-tuning. The suggested control algorithm is implemented on PRV III and the results of the test driving on a local road are given.

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Atmospheric Corrosion of 7B04 Aluminum Alloy in Marine Environments

  • Zhang, Xiaoyun;Liu, Ming;Lu, Feng;Liu, Minghui;Sun, Zhihua;Tang, Zhihui
    • Corrosion Science and Technology
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    • v.17 no.1
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    • pp.6-11
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    • 2018
  • Outdoor exposure tests using of 7B04 aluminium alloy samples including plate, tensile and various SCC samples were carried out in Tuandao station, Shandong province (East of China) and Wanning station, Hainan province (South of China). Corrosion characteristics including weight loss, microstructure, tensile strength and SCC susceptibility were investigated. The corrosion rates in Tuandao and Wanning showed high to low and the corrosion rates changed to the following equation of $w=at^b$ (b<1). The corrosion of 7B04 aluminium alloy in Wanning was more serious than that in Tuandao. Pitting appeared at early stage of expose test, and it can be changed to general corrosion with test time extension. The 7B04 aluminium alloy of which specimen shapes are forging and thick plate also showed SCC (Stress corrosion cracking) in the marine atmosphere. The higher SCC sensitivity was observed in Wanning station than in Tuandao station. The 7B04 aluminium alloy with a high stress level was more sensitive to SCC. Intergranular and transgranular or a mixed mode of cracking can be observed in different marine exposure.

FACTORS AFFECTING PRODUCTIVITY ON DAIRY FARMS IN TROPICAL AND SUB-TROPICAL ENVIRONMENTS

  • Kerr, D.V.;Davison, T.M.;Cowan, R.T.;Chaseling, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.5
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    • pp.505-513
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    • 1995
  • The major factors affecting productivity on daily farms in Queensland, Australia, were determined using the stepwise linear regression approach. The data were obtained from a survey conducted on the total population of daily farms in Queensland in 1987. These data were divided into six major dailying regions. The technique was applied using 12 independent variables believed by a panel of experienced research and extension personnel to exert the most influence on milk production. The regression equations were all significant (p < 0.001) with the percentage coefficients of determination ranging from 62 to 76% for equations developed using' total farm milk: production as the dependent variable. Three of the variables affecting total farm milk: production were found to be common to all six regions. These were; the amount of supplementary energy fed, the area set aside to irrigate winter feed and the size of the area used for dailying. Higher production farms appeared to be more efficient in that they consistently produced milk production levels higher than those estimated from the regression equation for their region. Other methods of analysis including robust regression and non linear regression techniques were unsuccessful in overcoming this problem and allowing development of a model appropriate for farms at all levels of production.

Study of a New Reciprocating Gait Orthosis for a Spinal Cord Injury Patient (척수마비환자 재활훈련용 왕복보행보조기에 관한 연구)

  • Kim, Myung-Hoe
    • Journal of Korean Physical Therapy Science
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    • v.9 no.1
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    • pp.81-88
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    • 2002
  • This paper presents a design and a control of a New Reciprocating Gait Orthosis and dynamic walking simulation for this system. The New Reciprocating Gait Orthosis is distinguished from other one by which has a very light-weight and a new RGO type with servo motors. The gait of a New Reciprocating Gait Orthosis depends on the constrains of mechanical kinematics and initial posture. The stability of dynamic walking is investigated by ZMP(Zero Moment Point) of the New Reciprocating Gait Orthosis. It is designed according to a human wear type and is able to accomodate itself to human environments. The joints of each leg are adopted with a good kinematic characteristics. To test of the analysis of joint kinematic properties, we did the strain stress analysis of dynamic PLS and the study of FEM with a dynamic PLS. It will be expect that the spinal card injury patients are able to train effectively with a Reciprocating Gait Orthosis. The New Reciprocating Gait Orthosis was able to keep smooth walling by the orthotic servo motors and hybrid system, make a sequence of flexion and extension of the joint during the walking. Also, the New Reciprocating Gait Orthosis turned out to be a satisfactory orthosis for walling training, for the spinal cord injury patient.

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