• Title/Summary/Keyword: Coverage Problem

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SDN based Proxy Mobile IPv6 for Horizontal and Vertical Handover in Vehicular Networks (차량 네트워크에서 수평 수직 핸드오버를 위한 SDN 기반 프록시 모바일 IPv6)

  • Raza, Syed Muhammad;Yeoum, Sanggil;Kim, Dongsoo;Choo, Hyunseung
    • Proceedings of the Korea Information Processing Society Conference
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    • 2014.11a
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    • pp.171-172
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    • 2014
  • This paper proposes a SDN based Proxy Mobile IPv6 (PMIPv6) architecture for heterogeneous vehicular networks (SDN-VANET), to provide the continuity of service during the horizontal handovers and to reduce the delay during vertical and horizontal handovers. SDN-VANET mainly relies on DSRC road side units (RSUs) for V2I communication and to overcome the coverage problem SDN-VANET performs the vertical handover between DSRC and LTE/UMTS. To date there is no standard to perform network layer vertical handovers. Therefore the proposed SDN-VANET architecture also doesn't provide any mechanism for vertical network layer handovers, but solves the horizontal network layer handovers in DSRC or LTE/UMTS through introducing PMIPv6 in the architecture.

Omni Scanning DPCA using Two Passive Antennas with Vertical Separation

  • Kim Man-Jo;Kho Bo-Yeon;Yoon Sang-Ho
    • Korean Journal of Remote Sensing
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    • v.22 no.3
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    • pp.229-234
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    • 2006
  • In tactical theater, it is crucial to detect ground moving targets and to locate them precisely. This problem can be resolved by using SAR (Synthetic Aperture Radar) sensors providing GMTI (Ground Moving Target Indication) capability. In general, to implement a robust GMTI sensor is not simple because of the strong competitions between target signals and clutter signals from the ground, and low speed of moving targets. Contrary to the case that a delay canceller is mostly suitable for ground surveillance radars, DPCA (Displaced Phase Centered Antenna) or STAP (Space Time Adaptive Processing) techniques have been widely adapted for GMTI function of modern airborne radars. In this paper, a new scheme of DPCA using two passive antennas with vertical separation is proposed, which also provides good clutter cancellation performance. The proposed scheme realizes full azimuth coverage for DPCA operation on an airborne platform, which is impossible with classical DPCA configuration. Simulations using various conditions have been performed to validate the proposed scheme, and the results are acceptable.

Identifying SDC-Causing Instructions Based on Random Forests Algorithm

  • Liu, LiPing;Ci, LinLin;Liu, Wei;Yang, Hui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.3
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    • pp.1566-1582
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    • 2019
  • Silent Data Corruptions (SDCs) is a serious reliability issue in many domains of computer system. The identification and protection of the program instructions that cause SDCs is one of the research hotspots in computer reliability field at present. A lot of solutions have already been proposed to solve this problem. However, many of them are hard to be applied widely due to time-consuming and expensive costs. This paper proposes an intelligent approach named SDCPredictor to identify the instructions that cause SDCs. SDCPredictor identifies SDC-causing Instructions depending on analyzing the static and dynamic features of instructions rather than fault injections. The experimental results demonstrate that SDCPredictor is highly accurate in predicting the SDCs proneness. It can achieve higher fault coverage than previous similar techniques in a moderate time cost.

Process for Automatic Requirement Generation in Korean Requirements Documents using NLP Machine Learning (NLP 기계 학습을 사용한 한글 요구사항 문서에서의 요구사항 자동 생성 프로세스)

  • Young Yun Baek;Soo Jin Park;Young Bum Park
    • Journal of the Semiconductor & Display Technology
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    • v.22 no.1
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    • pp.88-93
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    • 2023
  • In software engineering, requirement analysis is an important task throughout the process and takes up a high proportion. However, factors that fail to analyze requirements include communication failure, different understanding of the meaning of requirements, and failure to perform requirements normally. To solve this problem, we derived actors and behaviors using morpheme analysis and BERT algorithms in the Korean requirement document and constructed them as ontologies. A chatbot system with ontology data is constructed to derive a final system event list through Q&A with users. The chatbot system generates the derived system event list as a requirement diagram and a requirement specification and provides it to the user. Through the above system, diagrams and specifications with a level of coverage complied with Korean requirement documents were created.

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Cranioplasty Using Three-Dimensional-Printed Polycaprolactone Implant and Free Latissimus Dorsi Musculocutaneous Flap in a Patient with Repeated Wound Problem following Titanium Cranioplasty

  • Hee Tae Koo;Jeongseok Oh;Chan Yeong Heo
    • Archives of Plastic Surgery
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    • v.49 no.6
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    • pp.740-744
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    • 2022
  • Titanium mesh is an alloplastic material widely used for the reconstruction of moderate-to-large skull defects. Repeated wound problems or infection following these reconstructions inevitably lead to the replacement of the cranioplasty material. Among the various alloplastic materials, polycaprolactone implants are usually used for the coverage of small defects such as burr holes. Herein, we present a case of a large cranial defect successfully reconstructed with three-dimensional-printed polycaprolactone implant and a free latissimus dorsi musculocutaneous flap. Until 1-year followup, the patient showed a favorable esthetic outcome with no complications or wound relapse.

A Built-In Self-Test Architecture using Self-Scan Chains (자체 스캔 체인을 이용한 Built-In Self-Test 구조에 관한 연구)

  • Han, Jin-Uk;Min, Hyeong-Bok
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.39 no.3
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    • pp.85-97
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    • 2002
  • STUMPS has been widely used for built-in self-test of scan design with multiple scan chains. In the STUMPS architecture, there is very high correlation between the bit sequences in the adjacent scan chains. This correlation causes circuits lower the fault coverage. In order to solve this problem, an extra combinational circuit block(phase shifter) is placed between the LFSR and the inputs of STUMPS architecture despite the hardware overhead increase. This paper introduces an efficient test pattern generation technique and built-in self-test architecture for sequential circuits with multiple scan chains. The proposed test pattern generator is not used the input of LFSR and phase shifter, hence hardware overhead can be reduced and sufficiently high fault coverage is obtained. Only several XOR gates in each scan chain are required to modify the circuit for the scan BIST, so that the design is very simple.

FULL COVERAGE RESTORATION OF PRIMARY ANTERIOR TEETH : A CASE REPORT (유전치의 전장피개수복 : 증례보고)

  • Hong, Kee-Sang;Jang, Ki-Taeg;Lee, Sang-Hoon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.26 no.2
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    • pp.240-247
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    • 1999
  • Primary anterior teeth requiring extensive restorative therapy due to caries, trauma or developmental defects can present a particularly challenging problem for the pediatric dentist. The ideal restorative technique would combine strength, durability esthetics and efficiency in placement. Couple these concerns with the technical difficulties of operating on children with behavior management problems, and the dentist is left with the difficult task of choosing from a variety of restorative options. Restorative modalities currently in use to treat primary anterior teeth include bonding with composite resin as in celluloid strip crowns, conventional stainless steel crowns, open-faced stainless steel crowns, commercially and chairside veneered stainless steel crowns and epoxy-coated stainless steel crowns. Each of these techniques presents technical, functional or esthetic compromises that complicate their efficient and effective usage. This is a report of the results obtained at the Department of Pediatric Dentistry, College of Dentistry Seoul National University, through the use of these various methods of treating primary anterior teeth.

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A Simulation of Mobile Base Station Placement for HAP based Networks by Clustering of Mobile Ground Nodes (지상 이동 노드의 클러스터링을 이용한 HAP 기반 네트워크의 이동 기지국 배치 시뮬레이션)

  • Song, Ha-Yoon
    • Journal of Korea Multimedia Society
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    • v.11 no.11
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    • pp.1525-1535
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    • 2008
  • High Altitude Platform (HAP) based networks deploy network infrastructures of Mobile Base Station (MBS) in a form of Unmanned Aerial Vehicle (UAV) at stratosphere in order to build network configuration. The ultimate goal of HAP based network is a wireless network service for wide area by deploying multiple MBS for such area. In this paper we assume multiple UAVs over designated area and solve the MBS placement and coverage problem by clustering the mobile ground nodes. For this study we assumed area around Cheju island and nearby naval area where multiple mobile and fixed nodes are deployed and requires HAP based networking service. By simulation, visual results of stratospheric MBS placement have been presented. These results include clustering, MBS placement and coverage as well as dynamic reclustering according to the movement of mobile ground nodes.

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A Study on Improvements of Local Governments' Planting Regulations in Korea (우리 나라 지방자치단체 식재 조례 기준의 현황 및 개선방향)

  • 최일홍;황경희;이규목
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.2
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    • pp.194-206
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    • 1998
  • In 1977, Local governments' planting regulations for the development projects were established in accordance with the revised building law in Korea. A landscaped area, planting densities of trees and shrubs, a percentage of evergreen plants, minimum tree size and species were prescribed in the planting regulations. But the clauses for an excessive planting density and a high ratio of evergreen trees that the regulations includes, have been gradually in the way to a creative planting design, and raise a problem of poor growth of trees an a disordered planting landscape. Therefore, in this study the present planting regulations of 124 local governments throughout the country were analyzed and compared with 13 foreign local governments' of 4 countries ; Japan, the United States of America, Canada and Singapore. And the linitations and characteristics of the regulations are drawn as follows ; 1. The regulations focus on controlling the green spaces and plantings by quantitative methods such as controlling the number of trees and the landscaped area, which are inadequate for estimating the crown coverage of mature trees, and which areinadequate for estimating the crown coverage of mature trees, and implementing the function of polantings and the use of green spaces. 2. Minimums of tree densities are higher than those of foreign countries, especially higher about 10 times to 100 times than those of the United States of America. 3.Excessive number of evergreen trees and fruit trees should be planted under the present planting regulations, that results in constricting the creativity in planting design. 4. An article for using specific tree size, 2.0ms over in height makes it difficult to use a wide variety of different sizes of trees. And there is no incentive measures when larger trees are planted. To enhance the quality of green spaces and plantings, it is needed that the function and locating of green spaces and plantings have to be emphasized, and the planting density should be concerned about the mature tree size. The incentive measure to use various sizes of trees is also needed, and the regulations to use excessive number of evergreen trees or fruit trees should be loosened.

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Self-Sampling Versus Physicians' Sampling for Cervical Cancer Screening - Agreement of Cytological Diagnoses

  • Othman, Nor Hayati;Zaki, Fatma Hariati Mohamad;Hussain, Nik Hazlina Nik;Yusoff, Wan Zahanim Wan;Ismail, Pazuddin
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.7
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    • pp.3489-3494
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    • 2016
  • Background: A major problem with cervical cancer screening in countries which have no organized national screening program for cervical cancer is sub-optimal participation. Implementation of self-sampling method may increase the coverage. Objective: We determined the agreement of cytological diagnoses made on samples collected by women themselves (self-sampling) versus samples collected by physicians (Physician sampling). Materials and Methods: We invited women volunteers to undergo two procedures; cervical self-sampling using the Evalyn brush and physician sampling using a Cervex brush. The women were shown a video presentation on how to take their own cervical samples before the procedure. The samples taken by physicians were taken as per routine testing (Gold Standard). All samples were subjected to Thin Prep monolayer smears. The diagnoses made were according to the Bethesda classification. The results from these two sampling methods were analysed and compared. Results: A total of 367 women were recruited into the study, ranging from 22 to 65 years age. There was a significant good agreement of the cytological diagnoses made on the samples from the two sampling methods with the Kappa value of 0.568 (p=0.040). Using the cytological smears taken by physicians as the gold standard, the sensitivity of self-sampling was 71.9% (95% CI:70.9-72.8), the specificity was 86.6% (95% CI:85.7-87.5), the positive predictive value was 74.2% (95% CI:73.3-75.1) and the negative predictive value was 85.1% (95% CI: 84.2-86.0). Self-sampling smears (22.9%) allowed detection of micro-organisms better than physicians samples (18.5%). Conclusions: This study shows that samples taken by women themselves (self-sampling) and physicians have good diagnostic agreement. Self-sampling could be the method of choice in countries in which the coverage of women attending clinics for screening for cervical cancer is poor.