• Title/Summary/Keyword: time constraint

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Design of a Binding for the performance Improvement of 3D Engine based on the Embedded Mobile Java Environment (자바 기반 휴대용 임베디드 기기의 삼차원 엔진 성능 향상을 위한 바인딩 구현)

  • Kim, Young-Ouk;Roh, Young-Sup
    • Journal of Korea Multimedia Society
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    • v.10 no.11
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    • pp.1460-1471
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    • 2007
  • A 3-Dimensional engine in a mobile embedded device is divided into a C-based OpenGL/ES and a Java-based JSR184 which interprets and executes a byte code in a real-time. In these two standards, the JSR184 supporting Java objects uses more processor resources than an OpenGL/ES and thus has a constraint when it is used in an embedded device with a limited computing power. On the other hand, 3-Dimensional contents employed in existing personal computer are created by utilizing advantages of Java and secured numerous users in European market, due to the good quality in contents and extensive service in a commercial network, GSM. Because of the reason, a mobile embedded device used in a GSM network needs a JSR184 which can provide an existing Java-based 3-Dimensional contents without extra conversion processes, but the current version of Java-based 3-Dimensional engine has drawbacks in application to commercial products because it requires more computing power than the mobile embedded device. This paper proposes a binding technique with the advantages of Java objects to improve a processing speed of 3-Dimensional contents in limited resources of a mobile embedded device. The technique supports a JSR184 standard interface in the upper layer to utilize 3-Dimensional contents using Java, employs a different code-conversion language, KNI(Kilo Native Interface), in the middle layer to interface between OpenGL/ES and JSR184, and embodies an OpenGL/ES standard in the lower layer. The validity of the binding technique is demonstrated through a simulator and a FPGA embedding an ARM.

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Two Stage Dropping Scheme Considering Latency of rtPS Class in IEEE 802.16/WiBro System (IEEE 802.16/WiBro 시스템에서의 rtPS 클래스의 지연을 고려한 두 단계 드롭 기법)

  • Baek, Joo-Young;Yoon, Jong-Pil;Kim, Sok-Hyong;Suh, Young-Joo
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.8
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    • pp.783-787
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    • 2008
  • IEEE 802.16/WiBro, one of the representative Broadband Wireless Access (BWA) systems, defines QoS negotiation between BS and SS and five service classes to guarantee QoS for flows. The five service classes are UGS, ertPS, rtPS, nrtPS, and BE, but the standard does not define how to provide services to flows according to the service classes. Existing research works have been studied about the scheduler architecture to effectively utilize the IEEE 802.16/WiBro systems. These works use the original packet scheduling algorithm for service classes. However, it is necessary to consider bandwidth allocation mechanisms in scheduling algorithms since bandwidth allocation mechanisms are different according to service classes. Especially, bandwidth allocation mechanisms should be considered for the scheduling of rtPS class since rtPS class uses the polling mechanism that takes time to allocate bandwidth and has the minimum latency constraint. Therefore, we propose two stage dropping scheme for rtPS class that is sensitive to latency, and thus it reduces the wasted resources and provides efficient service to rtPS class.

Development and application of GLS OD matrix estimation with genetic algorithm for Seoul inner-ringroad (유전알고리즘을 이용한 OD 추정모형의 개발과 적용에 관한 연구 (서울시 내부순환도로를 대상으로))

  • 임용택;김현명;백승걸
    • Journal of Korean Society of Transportation
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    • v.18 no.4
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    • pp.117-126
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    • 2000
  • Conventional methods for collecting origin-destination trips have been mainly relied on the surveys of home or roadside interview. However, the methods tend to be costly, labor intensive and time disruptive to the trip makers, thus the methods are not considered suitable for Planning applications such as routing guidance, arterial management and information Provision, as the parts of deployments in Intelligent Transport Systems Motivated by the problems, more economic ways to estimate origin-destination trip tables have been studied since the late 1970s. Some of them, which have been estimating O-D table from link traffic counts are generally Entropy maximizing, Maximum likelihood, Generalized least squares(GLS), and Bayesian inference estimation etc. In the Paper, with user equilibrium constraint we formulate GLS problem for estimating O-D trips and develop a solution a1gorithm by using Genetic Algorithm, which has been known as a g1oba1 searching technique. For the purpose of evaluating the method, we apply it to Seoul inner ringroad and compare it with gradient method proposed by Spiess(1990). From the resu1ts we fond that the method developed in the Paper is superior to other.

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Asymptotical Shock Wave Model for Acceleration Flow

  • Cho, Seongkil
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.12 no.3
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    • pp.103-113
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    • 2013
  • Shock wave model describes the propagation speed of kinematic waves in traffic flow. It was first presented by Lighthill and Whitham and has been deployed to solve many traffic problems. A recent paper pointed out that there are some traffic situations in which shock waves are not observable in the field, whereas the model predicts the existence of waves. The paper attempted to identify how such a counterintuitive conclusion results from the L-W model, and resolved the problem by deriving a new asymptotical shock wave model. Although the asymptotical model successfully eliminated the paradox of the L-W model, the validation of the new model is confined within the realm of the deceleration flow situation since the model was derived under such constraint. The purpose of this paper is to derive the remaining counter asymptotical shock wave model for acceleration traffic flow. For this, the vehicle trajectories in a time-space diagram modified to accommodate the continuously increased speed at every instant in such a way that the relationship between the spacing from the preceding vehicle and the speed of the following vehicle strictly follows Greenshield's model. To verify the validity of the suggested model, it was initially implemented to a constant flow where no shock wave exists, and the results showed that there exists no imaginary shock wave in a homogeneous flow. Numerical applications of the new model showed that the shock wave speeds of the asymptotical model for the acceleration flow tend to lean far toward the forward direction consistently. This means that the asymptotical models performs in a systematically different way for acceleration and for declaration flows. Since the output difference among the models is so distinct and systematic, further study on identifying which model is more applicable to an empirical site is recommended.

Position Estimation of Autonomous Mobile Robot Using Geometric Information of a Moving Object (이동물체의 기하학적 위치정보를 이용한 자율이동로봇의 위치추정)

  • Jin, Tae-Seok;Lee, Jang-Myung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.14 no.4
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    • pp.438-444
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    • 2004
  • The intelligent robots that will be needed in the near future are human-friendly robots that are able to coexist with humans and support humans effectively. To realize this, robots need to recognize their position and posture in known environment as well as unknown environment. Moreover, it is necessary for their localization to occur naturally. It is desirable for a robot to estimate of his position by solving uncertainty for mobile robot navigation, as one of the best important problems. In this paper, we describe a method for the localization of a mobile robot using image information of a moving object. This method combines the observed position from dead-reckoning sensors and the estimated position from the images captured by a fixed camera to localize a mobile robot. Using the a priori known path of a moving object in the world coordinates and a perspective camera model, we derive the geometric constraint equations which represent the relation between image frame coordinates for a moving object and the estimated robot's position. Since the equations are based or the estimated position, the measurement error may exist all the time. The proposed method utilizes the error between the observed and estimated image coordinates to localize the mobile robot. The Kalman filter scheme is applied for this method. its performance is verified by the computer simulation and the experiment.

A Study on the Legal Issues relating to Navigation through Arctic Passage (국제법상 북극항로에서의 통항제도에 관한 연구)

  • Moon, Kyu-Eun
    • Strategy21
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    • s.43
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    • pp.29-55
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    • 2018
  • Arctic sea ice has been retreating as a result of the global warming. Arctic sea ice extent for April 2018 averaged 13.71 million square kilometers. This figure shows far less sea ice compared to the average extent from 1981 to 2010. Meanwhile, 287 times of maritime transits through the Northwest Passage have been made during the 2017 and the first ship traversed the Northern Sea Route without the assistant of ice-breaker in August 2017. Commercialization of the Arctic Passage means significant economic and strategic advantages by shortening the distance. In this article, 'Arctic Passage' means Northern Sea Route along the Arctic coast of Russia and Northwest Passage crossing Canadian Arctic Ocean. As climate changes, the potential feasibility of the Arctic Passage has been drawing international attention. Since navigation in this area remains hazardous in some aspects, IMO adopted Polar Code to promote safe, secure and sustainable shipping through the Arctic Passage. Futhermore, Russia and Canada regulate foreign vessels over the maritime zones with the authority to unilaterally exercise jurisdiction pursuant to the Article 234 of UNCLOS. The dispute over the navigation regime of the arctic passage materialized with Russia proclaimed Dmitrii Laptev and Sannikov Straits as historically belong to U.S.S.R. in the mid 1960s and Canada declared that the waters of the passage are historic internal waters in 1973 for the first time. So as to support their claims, In 1985, Russia and Canada established straight baseline including Northern Sea Route and Northwest Passage. The United States has consistently protested that the Northern Sea Route and Northwest Passage are straits used for international navigation which are subject to the regime of transit passage. Firstly, it seems that Russia and Canada do not meet the basic requirements for acquiring a historic title. Secondly, since the Law of the Sea had adopted before the establishment of straight baseline over the Russian Arctic Archipelago and the Canadian Arctic Archipelago, Ships can exercise at least the right of innocent passage. Lastly, Northern Sea Route and Northwest Passage have fulfilled the both geographical and functional criteria pertaining to the strait used for international navigation under the international law. Especially, should the arctic passage become commercially viable, it can be expected to accumulate the functional criterion. Russia and Canada regulate the ships navigate in their maritime zones by adopting the higher degree of an environmental standard than generally accepted international rules and standard mainly under the Article 234 of UNCLOS. However, the Article 234 must be interpreted restrictively as this contains constraint on the freedom of navigation. Thus, it is reasonable to consider that the Article 234 is limited only to the EEZ of coastal states. Therefore, ships navigating in the Arctic Passage with the legal status of the territorial sea and the international straits under the law of the sea have the right of innocent passage and transit passage as usual.

A research on remote X-ray detector design development for marketing in field diagnosis service (현장 진단 서비스 시장 공략을 위한 '무선 X-ray 디텍터' 디자인개발에 관한 연구)

  • Song, Seong Il
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.27 no.4
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    • pp.196-205
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    • 2017
  • In recent years, the service design in the medical sector evolves through practical service research and development that can visualize both intangible and intangible service elements in an integrative way and derive innovative solutions to help customers feel the service more important value. With the improvement of personal income, interest in medical welfare and well-being is increasing day by day, and the focus of the medical sector shifts from the concept of treatment of diseases and illness to preventive medicine. In response to this trend, research and development of home health care system, which greatly reduces the time and space constraint of health checkup and health care by combining ubiquitous concept with medical welfare, are being actively conducted, and the needs for improving products and medical environment based on user-centered medical service and user needs in accordance with the Health Care 3.0 Era, it becomes necessary to develop on-site medical diagnostic products that reflect user-centered needs and needs. This study is intended to research and develop a product that sufficiently reflects the needs of users by applying suitable materials and shape for on-site diagnostic product in researching and developing Wireless X-ray Detector.

A Study on Methods of Documentary Research on Educational Facilities - Focused on the Utilization of the ERIC - (교육시설(敎育施設)에 관한 문헌연구(文獻硏究) 방법(方法) - 미국 ERIC 자료 활용방법을 중심으로 -)

  • Park, Jae-Youn
    • Journal of the Korean Institute of Educational Facilities
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    • v.1 no.1
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    • pp.33-40
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    • 1994
  • This study was taken to increase efficiency in reviewing documents of school facilities from the network of ERIV(Educational Resources and Information Center, USA). Outline of the ERIC network, and the structure, role, function of the ERIC thesaurus are introduced. A thesaurus have developed for information retrieval purpose provides the filing labels which permit information to be stored by one person and retrieved by another. As an information system grows, its thesaurus is systematically built and refined to the point where it represents, in a very special sense, the vocabulary of subject field. The Thesaurus of ERIC Descriptors represents such a vocabulary for the field education. An understanding of its origins, its function and its limitations, is just as important to the teacher, the student of education or the educational researcher as it is for the indexer or custodian of the information pool it represents. If the Thesaurus is understood and used in an appropriate way, it can give all educators not only insight into the ERIC system but also an increased awareness of the language of their field. A great many terms are necessary to describe the many aspects of education, and the task of relating them in even an approximately consistent way is an enormous one. The undertaking should be managed by people who not only know what they are talking about but who also should be able to predict what people in their field are lilely to be talking about in the near future. It should also enlist people who are willing to pay term to another within the system. To engage a large number of these two kinds of people over a long period of time is very likely to cost a great deal of money. There is very little proprietary value in producing such a list of terms, for it can very easily be copied, adapted, updated, etc. Thus, because of its high cost and low proprietary value, it becomes a task likely to be funded only by a government. A government has many ways of spending its money. However, after the decision has been made to spend money to produce an authority list, one must decide how this authority is to be delegated. The history of the development of the ERIC Thesaurus is the history of how this authority was delegated. Scientific research has thrived on efforts to define terms as precisely as possible. It is difficult to say with certainty, however, that solutions to social problems have thrived on a simple diet of scientific research. Contemporary crises demand new and imaginative ways of conceiving problems and talking about them. If this Thesaurus or any other scheme for normalizing or controlling language inhibits in the slightest measure the creative use of language, it is against it use. Only if the principles and details of the Thesaurus are misunderstood can it be used as a constraint on language in a negative sense. Students of education of every kind should see the The-saurus as an opportunity to become increasingly self-conscious about their language and thus about their assumptions and their approaches to educational problems.

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Improved deformation energy for enhancing the visual quality of planar shape deformation (평면 형상 변형의 시각적 품질 향상을 위한 개선된 형상 변형 에너지)

  • Yoo, Kwangseok;Choi, Jung-Ju
    • Journal of the Korea Computer Graphics Society
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    • v.18 no.4
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    • pp.1-8
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    • 2012
  • We present improved deformation energy to enhance the visual quality of a shape deformation technique, where we preserve the local structure of an input planar shape. The deformation energy, in general, consists of several constraints such as Laplacian coordinate constraint to preserve the quality of deformed silhouette edges, mean value coordinates and edge length constraints to preserve the quality of deformed internal shape, and user-specified position constraints to control the shape deformation. When the positions of user-specified vertices change, shape deformation techniques compute the positions of the other vertices by means of nonlinear least squares optimization to minimize the deformation energy. When a user-specified vertex changes its position rapidly, it is frequently observed that the visual quality of the deformed shape decrease rapidly, which is mainly caused by unnecessary enlargement of the Laplacian vectors and unnecessary change of the edge directions along the boundary of the shape. In this paper, we propose improved deformation energy by prohibiting the Laplacian and edge length constraints from changing unnecessarily. The proposed deformation energy incorporated with well-known optimization technique can enhance the visual quality of shape deformation along the silhouette and within the interior of the planar shape while sacrificing only a little execution time.

Security of Ethernet in Automotive Electric/Electronic Architectures (차량 전자/전기 아키텍쳐에 이더넷 적용을 위한 보안 기술에 대한 연구)

  • Lee, Ho-Yong;Lee, Dong-Hoon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.5
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    • pp.39-48
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    • 2016
  • One of the major trends of automotive networking architecture is the introduction of automotive Ethernet. Ethernet is already used in single automotive applications (e.g. to connect high-data-rate sources as video cameras), it is expected that the ongoing standardization at IEEE (IEEE802.3bw - 100BASE-T1, respectively IEEE P802.3bp - 1000BASE-T1) will lead to a much broader adoption in future. Those applications will not be limited to simple point-to-point connections, but may affect Electric/Electronic(EE) Architectures as a whole. It is agreed that IP based traffic via Ethernet could be secured by application of well-established IP security protocols (e.g., IPSec, TLS) combined with additional components like, e.g., automotive firewall or IDS. In the case of safety and real-time related applications on resource constraint devices, the IP based communication is not the favorite option to be used with complicated and performance demanding TLS or IPSec. Those applications will be foreseeable incorporate Layer-2 based communication protocols as, e.g., currently standardized at IEEE[13]. The present paper reflects the state-of-the-art communication concepts with respect to security and identifies architectural challenges and potential solutions for future Ethernet Switch-based EE-Architectures. It also gives an overview and provide insights into the ongoing security relevant standardization activities concerning automotive Ethernet. Furthermore, the properties of non-automotive Ethernet security mechanisms as, e.g., IEEE 802.1AE aka. MACsec or 802.1X Port-based Network Access Control, will be evaluated and the applicability for automotive applications will be assessed.