• Journal of the Korean Institute of Navigation
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• v.1 no.1
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• pp.17-26
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• 1977

A large number of the set-nets are set in Namhaedo coast of Korea. The floats of these set-nets are not only small even in case of large floats but also they scarcely have distinguishable marks such as light buoys or flags, so that they are very hard to be recognized by naked eyes and thus became probable obstacles to navigation for the passing ships and the fishing vessels. In order to research the capability of detecting such nets with Radar, the author investigated a maximum detectable range of the ordinarly large floatsand of a floating corner reflectors of various size and shape by Radar. The results obtained are as follows; 1. A maximum detectable range of large floats at a close range can be calculated by the Radar equation in sufficient accuracy. 2. Large floats of the large set-nets are also detectable by Radar even though it's detectable range boundary was within 0.2-0.65 miles. And the Radar picture of large floats was easier to be found with somewhat higher setting of the gain control on shorter range scale of the 1 mile. 3. Floating corner reflector rather suitable for set-net floats of "S" type reflector proposed in this paper, of which the dimension must be above 17cm in diameter to be detectable by Radar at 2 miles.t 2 miles.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.6
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• pp.2151-2159
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• 2015

Pancreatic neuroendocrine tumors (pNETs) are rare and heterogenous tumors and surgery to remove the primary tumor is the mainstay of treatment for resectable disease. However, curative surgery is often not feasible, because half of patients with pNET have metastases at the time of diagnosis. Palliative dubulking surgery and liver-directed therapies are appropriate options for these patients. Streptozocin-based regimens are standard, although temozolamide-based treatments are rapidly gaining wide clinical application. Somatostatin analogs are mainly indicated in hormonally active tumors to ameliorate symptoms. In addition, anti-tumoral activity has been proven in well-differentiated NETs. Recently, there has been tremendous progress in the molecular biology of pNETs; thereby, the efficacy of sunitinib and everolimus in the treatment of patients with metastatic pNETs has been proven by large placebo-controlled phase III trials. Currently, there are no definitively proven predictive biomarkers to evaluate response to medical therapies in patients with pNET. Therefore, further studies are needed to individualize and optimize their management. This article reviews systemic chemotherapy, targeted therapies, and anti-secretory treatments for the management of patients with unresectable or metastatic pNETs, summarized in the light of recent advances.

• The Journal of Korea Robotics Society
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• v.11 no.3
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• pp.115-126
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• 2016

This paper suggests the method of the spherical signature description of 3D point clouds taken from the laser range scanner on the ground vehicle. Based on the spherical signature description of each point, the extractor of significant environmental features is learned by the Deep Belief Nets for the urban structure classification. Arbitrary point among the 3D point cloud can represents its signature in its sky surface by using several neighborhood points. The unit spherical surface centered on that point can be considered to accumulate the evidence of each angular tessellation. According to a kind of point area such as wall, ground, tree, car, and so on, the results of spherical signature description look so different each other. These data can be applied into the Deep Belief Nets, which is one of the Deep Neural Networks, for learning the environmental feature extractor. With this learned feature extractor, 3D points can be classified due to its urban structures well. Experimental results prove that the proposed method based on the spherical signature description and the Deep Belief Nets is suitable for the mobile robots in terms of the classification accuracy.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.7 no.1
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• pp.11-18
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• 1989

Observations to precise levelling nets contain different types of error because it has been caried out with various instruments and techniques, and also completed through long period. In order to establish a precise levelling nets, therefore, the weight function has to be selected adequately in the adjustment of nets. The purpose of the study is to determine a suitable weight function for the first order geodetic levelling nets in Korea and, therefore, the various numerical tests are performed with different statistical error models. The result of the study shows that the weight function, W＝1/$L^2$ is more efficient than W＝1/L in the first order levelling nets in the Korea.

• Proceedings of The KACE
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• 2018.08a
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• pp.3-6
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• 2018

2015 개정 교육과정에 따라 2019년 3월부터 초등학교 5~6학년 학생을 대상으로 소프트웨어 교육이 실시된다. 궁극적인 소프트웨어 교육의 목표는 컴퓨팅 사고력을 갖춘 창의 융합형 인재를 양성하는 것이다. 이를 위해 초등학교에서는 알고리즘과 프로그래밍의 체험을 통해 소프트웨어 기초 소양을 함양하는 것을 목표로 한다. 이러한 컴퓨팅 사고력을 수업에 효과적으로 적용하기 위해 전용주(2017)는 소프트웨어 및 컴퓨팅에 관련된 사고과정과 원리를 실생활의 소재와 관련지어 창의적이고 능동적으로 그 해결방안을 구현해가는 과정으로 제시할 수 있는 수업 구성 원리인 CT-CPS 수업 모형을 개발하였다. 또한 교육부는 2015 개정 교육과정 실시 전, 소프트웨어 교육을 위한 선도학교를 전국에 지정하여 운영하였다. 선도학교에서의 소프트웨어 교육과정을 분석한 결과 주로 컴퓨팅 사고력의 구성요소 중 알고리즘과 자동화에 초점이 맞춰져 있었다. 엔트리와 스크래치와 같은 블록 프로그래밍 도구를 사용한 코딩교육과 로봇교육을 주로 실시했고, 실제 문제에 대한 학생들이 자료를 직접 다루는 시간은 찾아보기 힘들었다. 컴퓨팅사고력 향상을 위해서는 학생들이 실제 자료를 수집, 분석, 표현해보는 활동이 반드시 필요하다. 이에 본 연구에서 NetsBlox을 활용하고자 한다. NetsBlox는 학생들에게 익숙한 블록형 프로그래밍 도구로 실제 데이터를 온라인상에서 쉽게 받아와서 수집, 분석, 표현을 하게 도와주는 역할을 한다. 따라서 본 연구에서는 초등학생을 위한 NetsBlox를 활용한 CT-CPS기반 프로그래밍 수업을 설계하고자 한다.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.67-75
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• 2010

Deadlock usually appears in contain subsystem which is run in parallel and resources share modules. Siphons and traps have been well introduced to characterize deadlocks of Petri nets. Siphon concept be well used for proposing the detect and prevent deadlock by the pleasure researchers. But it's need many times and efforts to detect all siphon sub-nets in the Petri model. Since transitive matrix could explain all relations between the place and transitions in Petri nets, we propose an algorithm to detect all siphon sub-nets after analyzed the transitive matrix's properties. Examples are givens to illustrate the method.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1504-1507
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• 1997

In this paper, we investigate a traffic flow modeled by stochastic Petri nets. The model consists of two parts : the traffic flow model and signal controller model. These models are used for analyzing the flow of the traffic intersection. The results of the evaluation are derived from a Petri Net-based simulation package, Greatspn. Through simulation we compare the performances of the pretimed signal controller with those of the trafic-adaptive signal controller.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.699-705
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• 2009

This paper reviews methods used to perform reliability and availability analysis of the network system composed by nodes and links. The combination of nodes and links forms virtual connections (VC). The failure of several VCs cause failure of whole network system. Petri Net models are used to analyze the reliability and availability. Stochastic reward nets (SRN) is an extension of stochastic Petri nets provides modelling facilities for network system analysis.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.336-341
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• 1993

Automatic Assembly Systems(AAS) are a class of systems exhibiting concurrency, asynchronicity and distributedness, and can be modeled by Petri Nets. In this paper, we design two types of configuration of part-assembly system in the car manufacturing line, as an example of AAS. And, we make a modeling the system by utilizing Extended Petri Nets, simulation as varying machine parameters, and analysis of operation status. These enable to present the information of optimal status and various problems occurring in the system for achieving high production rate.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.2
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• pp.1-7
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• 1993

In this paper, we show that Petri nets can be applied to design and reliability analysis of concurrent, parallel and embedded mode system such as a lift system that is familiar to our daily life. Modeling the behavioral characteristics of the lift system we extend the standard Petri nets by nadditionally constant timed transition, fault transition, stochastic imed ttransition and conditional transition concepts. Likewise, we present esults of rdesign and analysis of the system. This method can be applied to esign and danalysis of any other concurrent systems.