• Title/Summary/Keyword: Interference Management

Search Result 442, Processing Time 0.024 seconds

The Current Number of Its Individuals and Management Plan of Roe Deer(Capreolus pygarus tianschanicus Satunin) Inhabiting Mt. Halla(Hallasan), Jeju Island, Korea (한라산에 서식하는 노루(Capreolus pygarus tianschanicus Satunin)의 개체수 현황과 관리방안)

  • Kim, Byoung-Soo;Oh, Jang-Geun;Oh, Hong-Shik
    • Korean Journal of Environment and Ecology
    • /
    • v.21 no.4
    • /
    • pp.366-373
    • /
    • 2007
  • This study researched the number of individuals of Roe deer (Capreolus pygarus tianschanicus Satunin), which inhabit Mt. Halla (Hallasan) National Park and its neighboring areas ranging about $270km^2$ areas. The research was done from November(late fall), 1998 to March(early spring), 2001, and additional research was carried out from November 2006 to January 2007. As a result of this, we identified a total of 1,444 deer, and found out the fact that there lived 5.33 deer per $km^2$. By region, we identified a maximum of 270 deer at Donnaeko hiking path and a minimum of 12 deer at the adjacent areas to the second Sanrok-road. The frequency of Roe deer group sighting was higher at the edge of Hallasan National Park than any other surveyed region. Thus, it is estimated that the distribution of Roe deer of Hallasan is more influenced by the quantity and quality of food than human-made interference during wintry season.

Improved Trilateration Method on USN for reducing the Error of a Moving Node Position Measurement (무선센서네트워크에서 삼변측량법 기반 이동노드 위치 오차를 줄이는 탐색기법)

  • Mun, Hyung-Jin;Jeong, Hee-Young;Han, Kun-Hee
    • Journal of Digital Convergence
    • /
    • v.14 no.5
    • /
    • pp.301-307
    • /
    • 2016
  • The location measurement technique of moving worker in dangerous areas, is necessary for safety in the mines, basements, warehouses, etc. There are various measurement techniques about moving node of position in a restricted environment. Trigonometric Method, one of measurement techniques, is commonly used because of its easiness. However, errors occur frequently when measuring distance and position due to radio interference and physical disability with measuring instruments. This paper proposed a method which is more accurate and shows reduced margin of error than existing trigonometric method by recalculating distance between Anchor and moving node with various measuring instruments. By adding Anchor when calculating distance and position of moving node's estimated point, suggested technique obtains at least 41% efficiency compared to existing method.

A Robust Biometric-based User Authentication Protocol in Wireless Sensor Network Environment (무선센서네트워크 환경에서 생체기반의 개선된 사용자 인증 프로토콜)

  • Shin, Kwang-Cheul
    • The Journal of Society for e-Business Studies
    • /
    • v.18 no.3
    • /
    • pp.107-123
    • /
    • 2013
  • In a wireless sensor network environment, it is required to ensure anonymity by keeping sensor nodes' identifiers not being revealed and to support real-time authentication, lightweight authentication and synchronization. In particular, there exist possibilities of location information leakage by others, privacy interference and security vulnerability when it comes to wireless telecommunications. Anonymity has been an importance issue in wired and wireless network environment, so that it has been studied in wide range. The sensor nodes are interconnected among them based on wireless network. In terms of the sensor node, the researchers have been emphasizing on its calculating performance limit, storage device limit, and smaller power source. To improve of biometric-based D. He scheme, this study proposes a real-time authentication protocol using Unique Random Sequence Code(URSC) and variable identifier for enhancing network performance and retaining anonymity provision.

Design of a 5-patch GPS array antenna for anti-jamming (GPS 방해신호 회피용 5-패치 배열 안테나 설계)

  • Chae, Gyoo-Soo;Lim, Joong-Soo
    • Journal of Digital Convergence
    • /
    • v.11 no.12
    • /
    • pp.417-422
    • /
    • 2013
  • In this paper, the implementation of a null-steering antenna array using GPS patch antennas is suggested. The antenna array consists of five patch antenna elements fabricated on the ceramic substrate. The antenna element proposed here is a typical circular polarization patch and a prototype patch array antenna is manufactured on the PCB. The antenna has one reference element located at the center and other four elements are placed at the corners. A null in the direction of the jamming signal can be produced by changing the phases of 4-elements. Simulation results of the array antenna by CST MWS are presented and discussed. The basic performances are measured and the results are shown. The results show that the antenna presented here can be used to remove the signals from the directions of any jammers.

Universal and Can be Applied Wireless Channel Assignment Algorithm (범용 적용이 가능한 무선채널할당알고리즘)

  • Heo, Seo-Jung;Son, Dong-Cheul;Kim, Chang-Suk
    • Journal of Digital Convergence
    • /
    • v.10 no.9
    • /
    • pp.375-381
    • /
    • 2012
  • If a mobile station requests a channel allocation in its mobile networks, the switching center assigns a channel to a mobile station that belongs to each base station. There are three kinds of channel allocation schemes; a fixed channel allocation, a dynamic channel allocation and a hybrid combination of these two forms. In assigning a good frequency, it is our intention to provide quality service to our customers as well as to use resources efficiently. This paper proposes methods of assigning frequencies that minimize interference between channels and that also minimize the amount of searching time involved. In this paper, we propose an algorithm to per specific equipment, regardless of the number of channels that can be used as a general-purpose system, such as base stations, control stations, central office model is proposed, the existing operators manner similar to the fixed channel allocation based statistics and assigned when the conventional method and the improved method is proposed. Different ways and compared via simulations to verify the effectiveness of the proposed approach.

A Study on Factors Influencing Turnover of Public Parking Lots in Incheon Metropolitan City (인천광역시 공영주차장 이용실태 분석 기반 주차 회전율 영향요인 연구)

  • CHOI, Younghoon;KIM, Eungcheol
    • Journal of Urban Science
    • /
    • v.6 no.2
    • /
    • pp.29-34
    • /
    • 2017
  • Although the supply of public parking lots in major cities is steadily increasing, there is still a shortage of parking spaces that take into account the characteristics of actual available parking spaces. These parking problems are caused by conflicts between users, illegal occupation and privatization of roads, interference with traffic roads, and business stagnation in commercial areas and illegal parking problems. In addition, despite various parking demand management policies and continuous supply of public parking facilities, the solution to the parking problem is uneasy due to increased construction costs and changes in social conditions. In order to solve this problem, it was judged that it would be necessary to utilize the existing public parking lots efficiently. Therefore, we collect the variables expected to affect the turnover, and use multiple regression models. The results are summarized as follows. Firstly, public parking lots can be classified into four types using utilization rate and turnover rate. Secondly, influencing factors are found including index of public transportation usage convenience, index of illegal parking, and land use characteristics in central commercial district. Thirdly, it was shown that there was little impact by the size of public parking lots, separation distance to subway distance, separation distance to bus stops, transfer zone, residential zone, and second-rated lots by parking costs. Finally, it is found that public parking lots can be improved by proving accessibility of public transit, enforcement of illegal parking, active approaches supporting public parking lots. It is also recommended that public parking cost rating system based mainly on land use characteristics should be remedied and rearranged.

  • PDF

Quantitative and Qualitative Gradient of Pain Experience, Sleep Quality and Psychological Distress in Patients with Different Phenotypes of Temporomandibular Disorders

  • Choi, Hee Hun;Kim, Hye-Kyoung;Kim, Mee-Eun
    • Journal of Oral Medicine and Pain
    • /
    • v.45 no.3
    • /
    • pp.56-64
    • /
    • 2020
  • Purpose: Temporomandibular disorders (TMD) is a mosaic of clinical signs and symptoms that can be regarded as a set of phenotypes that are affected by various factors including pain sensitivity, pain disability, sleep and psychological functioning. The aims of this study were to evaluate association of pain experience, sleep quality and psychological distress with different phenotypes of TMD patients. Methods: This retrospective study included a cohort (n=1,858; 63.8% for female, mean age=34.9±15.9 years) of patients with TMD. A set of self-administered questionnaires concerning pain interference (Brief Pain Inventory), pain disability (Graded Chronic Pain Scale), sleep quality (Pittsburg Sleep Questionnaire Index), psychological distress (Symptom Checklist-90 revised), and pain catastrophizing (Pain Catastrophizing Scale) were administered to all participants at the first consultation. All TMD patients were classified into four groups including TMD with internal derangement without pain (TMD_ID, n=370), TMD with joint pain (TMD_J, n=571), TMD with muscle pain (TMD_M, n=541) and TMD with muscle-joint combined pain (TMD_MJ, n=376). Results: The female ratio was particularly high in the group with TMD_MJ (p=0.001). The patients with muscle pain and both muscle and joint pain had longer symptom duration (p=0.004) and presented significantly higher scores in pain experience (p<0.001), subjective sleep quality (p<0.001), pain catastrophizing (p<0.001) and psychological distress (p<0.05) except for paranoid-ideation than the groups with only joint problems. Conclusions: The results of this study highlight the importance of multi-dimensional approach that consider pain disability, sleep quality, and psychological functioning in the management of TMD with muscle component. This study would contribute to a better understanding of interaction between heterogeneous TMD and multiple risk factors in order to build tailored treatment based on different phenotypes.

Development of Designation Criteria for Ecological Protected Areas and its Application Methodology (생태계 보호지역의 합리적 지정을 위한 평가방법의 개발과 적용방안)

  • Park, Yong-Ha;Lee, Hyun-Woo;Kim, Ki-Gyoung;Lee, Gwan-Gyu;Choi, Jae-Yong;Heo, Soo-Jin;Seo, Gyoung-Won
    • Journal of Environmental Impact Assessment
    • /
    • v.17 no.3
    • /
    • pp.177-188
    • /
    • 2008
  • Attempts to develope designation criteria for ecological protected areas were made for rational and scientific designation and management of 'ecosystem and landscape conservation areas', 'wetland protection areas', 'special islands protection areas', and 'wildlife protected areas' which have been designated and managed by the Ministry of Environment. Through analysis of the requisites and criteria of IUCN, UNESCO, Natura 2000, the Ramsar convention, the United States, the United Kingdom, Japan, and Germany as well as various academic researches, evaluation items of the protected areas were classified into naturalness, biodiversity, ecosystem, and scientific values. These classification titles are reflection of Korean laws concerning the 4 protected areas described above. Of these items 'naturalness' is composed of 3 factors of wilderness, geomorphology and landscape, and vegetation. 'Biodiversity' is composed of the 5 factors of species diversity, endangered species, rare species, indigenous biological resources, and habitat of wetland wild animals. 'Ecosystem' is composed of 5 factors of typicalness, diversity, rarity, restoration ability, and degree of interference. All factors are scored using a 3 point scale of high, middle, or low and are then transformed into the numerical index for designating and zoning purposes. Conclusively, it is expected that the developed methodology will be highly applicable with field verifications.

The Difference in Patient Satisfaction Scores According to a Questionnaire Delivered by Hospital Staff and by Independent Surveyors (조사자에 따른 환자만족도 조사결과의 차이분석)

  • Cho, Woohyun;Lee, Sunhee;Choi, Kuison;Lim, Eunju;Kang, Myungguen
    • Quality Improvement in Health Care
    • /
    • v.6 no.1_2
    • /
    • pp.108-119
    • /
    • 1999
  • Background : To study any interference of demonstrated in different patient satisfaction scores for the same questionnaires handled by hospital staff and by independent surveyors, respectively. Methods : This study included 728 subjects who were admitted to a university hospital from June 22 to July 1, 1999. The contents of the questionnaire were composed of six dimensions: hospital structure and process, staffs technical competence and humaneness, information & education and communication. Measurements were performed on a 5-score Likert scale. T-test and logistic regression analysis were also performed. Results : In an outpatient survey, satisfaction scores from a questionnaire delivered by hospital staff were significantly higher than independent surveyors for the dimension of communication, but no differences were shown among other dimensions. In an inpatient survey, satisfaction scores by hospital staff were higher for the process and communication dimensions(p<0.05). In particular, in both the inpatient and outpatient surveys, the difference of satisfaction scores for personnel items were significant between groups. After adjustment for age and sex those differences were significant between groups. Conclusion : To minimize the bias on questionnaire survey, the effects of personnel, who deliver and gather the questionnaire should be carefully considered in the evaluation of health service satisfaction.

  • PDF

Performance Analysis of D2D system Considering users' locations under the Overlay Convergent Networks of Cognitive Networking (인지기반 중첩 융합 네트워크에서 위치정보에 기반한 D2D 시스템의 성능분석)

  • Kim, Jeong-Ho
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.51 no.10
    • /
    • pp.3-10
    • /
    • 2014
  • In this paper, the performances of the presented D2D (device-to-device) systems under the environment of the cognitive convergent overlay networks are evaluated based upon the locations of the D2D users' terminals, the power consumptions of the terminals and the reductions of the interference levels. As the capabilities of the users' terminals improve, the optimization of the system is crucial to the efficient utilization of the radio resources of the individual networks considering their mobility and the features of their networks. Users' mobility model is given for the performance evaluation of the D2D system. In this paper, the performances of the D2D systems are evaluated in terms of the performance index of the FER (frame error rate) employing multiantenna techniques (MIMO:multiple input multiple output) for the various network environments.