• Title/Summary/Keyword: point-to-point links

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A Study on the Method for Three-dimensional Geo-positioning Using Heterogeneous Satellite Stereo Images (이종위성 스테레오 영상의 3차원 위치 결정 방법 연구)

  • Jaehoon, Jeong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.4
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    • pp.325-331
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    • 2015
  • This paper suggests an intersection method to improve the accuracy of three-dimensional position from heterogeneous satellite stereo images, and addresses validation of the suggested method following the experimental results. The three-dimensional position is achieved by determining an intersection point of two rays that have been precisely adjusted through the sensor orientation. In case of conventional homogeneous satellite stereo images, the intersection point is generally determined as a mid-point of the shortest line that links two rays in at least square fashion. In this paper, a refined method, which determines the intersection point upon the ray adjusted at the higher resolution image, was used to improve the positioning accuracy of heterogeneous satellite images. Those heterogeneous satellite stereo pairs were constituted using two KOMPSAT-2 and QuickBird images of covering the same area. Also, the positioning results were visually compared in between the conventional intersection and the refined intersection, while the quantitative analysis was performed. The results demonstrated that the potential of refined intersection improved the positioning accuracy of heterogeneous satellite stereo pairs; especially, with a weak geometry of the heterogeneous satellite stereo, the greater effects on the accuracy improvement.

Differences in Epidermal Growth Factor Receptor Gene Mutations and Relationship with Clinicopathological Features in NSCLC Between Uygur and Han Ethnic Groups

  • Zhang, Yan;Wang, Qiang;Han, Zhi-Gang;Shan, Li
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.2879-2883
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    • 2013
  • Objective: To investigate differences in mutations of epidermal growth factor receptor (EGFR) gene and relationships with clinicopathological features in patients with non-small cell lung cancer (NSCLC) between Uygur and Han ethnic groups. Methods: The Scorpions amplification refractory mutation system (Scorpions ARMS) was used to measure mutations in exons 18, 19, 20 and 21 of the EGFR gene in paraffin-embedded tumor tissue from NSCLC cases, and statistical analysis was performed to investigate links with clinicopathological features in different histological types of NSCLC. Results: Results from ARMS testing showed EGFR mutations in tumor tissues from six (6) of 50 NSCLC patients of Uygur ethnic group, with a positive rate of 12.0%; four of them (4) had exon 19 deletion in EGFR, and two (2) had L858R point mutation in exon 21 of EGFR. Statistically significant difference was noted in EGFR genetic mutation between adenocarcinoma and non-adenocarcinoma (P < 0.05), but no differences with gender, age group, smoking status, or stage (P > 0.05). EGFR mutations were detected in tumor tissues from 27 of 49 NSCLC patients of Han ethnic group, with a positive rate of 55.1%; 19 of them had exon 19 deletions, seven (7) had L858R point mutations in exon 21 of EGFR and one (1) had mutations in both exon 18 G719X and exon 20 T790M of EGFR. Statistically significant differences were noted in EGFR genetic mutations between genders and between adenocarcinoma and non-adenocarcinoma (P<0.05), but not with age group, smoking status, or stage (P > 0.05). Conclusion: Statistically significant differences were noted in the positive rates of EGFR genetic mutations in NSCLC patients between Uygur and Han ethnic groups, with lower positive rates for the Uygur cases.

Scalable CC-NUMA System using Repeater Node (리피터 노드를 이용한 Scalable CC-NUMA 시스템)

  • Kyoung, Jin-Mi;Jhang, Seong-Tae
    • Journal of KIISE:Computer Systems and Theory
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    • v.29 no.9
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    • pp.503-513
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    • 2002
  • Since CC-NUMA architecture has to access remote memory, the interconnection network determines the performance of the CC-NUMA system. Bus which has been used as a popular interconnection network has many limits in a large-scale system because of the limited physical scalability and bandwidth. The dual ring interconnection network, composed of high-speed point-to-point links, is made to resolve the defects of the bus for the large-scale system. However, it also has a problem, in that the response latency is rapidly increased when many nodes are attached to the snooping based CC-NUMA system with the dual ring. In this paper, we propose a ring architecture with repeater nodes in order to overcome the problem of the dual ring on a snooping based CC-NUMA system, and design a repeater node adapted to this architecture. We will also analyze the effects of proposed architecture on the system performance and the response latency by using a probability-driven simulator.

A model of a relative evaluation of the transfer distance between two modes (환승센터의 두 수단간 환승거리의 상대적 적정성 평가)

  • Cha, Dong-Deuk;O, Jae-Hak;Park, Wan-Yong;Park, Seon-Bok
    • Journal of Korean Society of Transportation
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    • v.27 no.1
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    • pp.35-42
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    • 2009
  • One of the problems we face up at the time of planning or improving a transportation transfer facility is which modes and how close we have to put together. The goal here is to keep the connecting transportation mode as close as possible to the prime transit mode, so people travel a minimum transfer path, a distance from one mode to another. Too much a physical separation between modes will limit, even with an intensive improvement of the component links, the level of service of a transfer path as a whole. This study defined a transfer path as the whole stretch of the distance from an arrival point of one mode to the departure point of the connecting mode. The transfer path was divided into three typical segments as side walk, stairways, and indoor corridors. Preference surveys were made for each of these segments, resulting in relative resistance. The sum of individual segments weighted with the relative resistance will make a transfer resistance of the path, which in turn constitutes a transfer utility function together with the overall satisfaction score obtained by the interview survey. The transfer utility function has been utilized to evaluate the transfer distance between modes.

Road network data matching using the network division technique (네트워크 분할 기법을 이용한 도로 네트워크 데이터 정합)

  • Huh, Yong;Son, Whamin;Lee, Jeabin
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.4
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    • pp.285-292
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    • 2013
  • This study proposes a network matching method based on a network division technique. The proposed method generates polygons surrounded by links of the original network dataset, and detects corresponding polygon group pairs using a intersection-based graph clustering. Then corresponding sub-network pairs are obtained from the polygon group pairs. To perform the geometric correction between them, the Iterative Closest Points algorithm is applied to the nodes of each corresponding sub-networks pair. Finally, Hausdorff distance analysis is applied to find link pairs of networks. To assess the feasibility of the algorithm, we apply it to the networks from the KTDB center and commercial CNS company. In the experiments, several Hausdorff distance thresholds from 3m to 18m with 3m intervals are tested and, finally, we can get the F-measure of 0.99 when using the threshold of 15m.

Individualized Learning System based on Learning Object, through Semantic Sequencing by Learning Task Types (학습과제 유형별 유의미 연결을 통한 학습객체 기반 개별화 학습 시스템)

  • Hong, Ji-Young;Song, Ki-Sang
    • The Journal of Korean Association of Computer Education
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    • v.7 no.6
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    • pp.47-58
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    • 2004
  • To generate individualized and adaptive course, it's required to have the foundation structure in which learning objects are connected with each other with logical relevances. Each learner can have peculiar learning path at each point of time of learning through the logical relevancy between those learning objects and various links, considering individual learner. The purpose of this study is to design a learning object-basis individualized learning system structure, considering semantic sequencing by learning task types. It is our understanding that the individualized learning system design model of this study, considering the relevancy between learning objects, can be a fresh trial to accommodate semantic learning and true educational spirits in e-Learning at this point of time when criticism, such as the learning object based course design is simply a collection of meaningless objects, etc., is becoming influential.

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Capacity Bounds in Random Wireless Networks

  • Babaei, Alireza;Agrawal, Prathima;Jabbari, Bijan
    • Journal of Communications and Networks
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    • v.14 no.1
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    • pp.1-9
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    • 2012
  • We consider a receiving node, located at the origin, and a Poisson point process (PPP) that models the locations of the desired transmitter as well as the interferers. Interference is known to be non-Gaussian in this scenario. The capacity bounds for additive non-Gaussian channels depend not only on the power of interference (i.e., up to second order statistics) but also on its entropy power which is influenced by higher order statistics as well. Therefore, a complete statistical characterization of interference is required to obtain the capacity bounds. While the statistics of sum of signal and interference is known in closed form, the statistics of interference highly depends on the location of the desired transmitter. In this paper, we show that there is a tradeoff between entropy power of interference on the one hand and signal and interference power on the other hand which have conflicting effects on the channel capacity. We obtain closed form results for the cumulants of the interference, when the desired transmitter node is an arbitrary neighbor of the receiver. We show that to find the cumulants, joint statistics of distances in the PPP will be required which we obtain in closed form. Using the cumulants, we approximate the interference entropy power and obtain bounds on the capacity of the channel between an arbitrary transmitter and the receiver. Our results provide insight and shed light on the capacity of links in a Poisson network. In particular, we show that, in a Poisson network, the closest hop is not necessarily the highest capacity link.

Optimized design of Jansen mechanism based on target trajectory tracking method using multi-objective genetic algorithm (Multi-objective Genetic Algorithm 을 이용한 얀센 메커니즘의 목표 궤적 트래킹 기반 최적 설계)

  • Heo, Joon;Hur, Youngkun
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.455-462
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    • 2016
  • Recently, followed by rapid growth of robotics field, multi-linkage mechanism which can even pass by rough road is getting lots of attention. In this paper, I focused on Jansen mechanism. It's a kinematics object which is named after Dutch artist Theo jansen. Jansen mechanism embraces structure and mechanism which creates locomotion with the combination of the power and simple structure. Theo jansen suggests a 'Holy number'. It's an ideal ratio of leg components length. However, if there's desired gait locomotion, you have to adjust the ratio and the length. But even slight change of the length could cause a big change at the end-point. To solve this problem, I suggest a reverse engineering method to get a ratio of each links by nonlinear optimization with pre-set desired trajectory. First, we converted a movement of the joint of Jansen mechanism to vectors by kinematics analysis of multi-linkage structure. And we showed the trajectory at the end-point. After that, we set desired trajectory which we found most ideal. Then we got the length of the leg components which draws a trajectory as same as trajectory we set, using Multi-objective genetic algorithm toolbox in MATLAB. Result is verified by Edison designer and mSketch. And we analyzed if it could pass through the obstruction which is set dynamically.

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Geolocation Spectrum Database Assisted Optimal Power Allocation: Device-to-Device Communications in TV White Space

  • Xue, Zhen;Shen, Liang;Ding, Guoru;Wu, Qihui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.12
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    • pp.4835-4855
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    • 2015
  • TV white space (TVWS) is showing promise to become the first widespread practical application of cognitive technology. In fact, regulators worldwide are beginning to allow access to the TV band for secondary users, on the provision that they access the geolocation database. Device-to-device (D2D) can improve the spectrum efficiency, but large-scale D2D communications that underlie TVWS may generate undesirable interference to TV receivers and cause severe mutual interference. In this paper, we use an established geolocation database to investigate the power allocation problem, in order to maximize the total sum throughput of D2D links in TVWS while guaranteeing the quality-of-service (QoS) requirement for both D2D links and TV receivers. Firstly, we formulate an optimization problem based on the system model, which is nonconvex and intractable. Secondly, we use an effective approach to convert the original problem into a series of convex problems and we solve these problems using interior point methods that have polynomial computational complexity. Additionally, we propose an iterative algorithm based on the barrier method to locate the optimal solution. Simulation results show that the proposed algorithm has strong performance with high approximation accuracy for both small and large dimensional problems, and it is superior to both the active set algorithm and genetic algorithm.

A Group Key Management for Real-Time Multicasting Information Security (실시간 멀티캐스팅 정보보안을 위한 그룹키 관리)

  • Hong, Jong-Joon;Hwang, Kyo-Chul
    • The KIPS Transactions:PartC
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    • v.10C no.6
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    • pp.809-814
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    • 2003
  • The multicast transmitting the real-time data to groups may easily have many attacks from abnormal attacks because it has many links as compared to the unicast. The existing group key management architectures for preventing these problems are designed for protocols suitable for a large scale. Thus these architectures applied to a small scale routing protocols may have many overheads with key distribution and a constant core tree. Therefore this paper proposes a groups key management protocol for a secure multicast in PIM-SM multicast group communication. The proposed method divide multicast groups with RO(Rendezvous-Point), and subgroup key managers are established in each RP and can be transmitted groups keys between senders and receivers, so the security cannel is set up for secure data transfer, And this does not have needs of the data translation for group keys and the new key distribution for path change. As a result of this, the data transmission time can be reduced.