• Title/Summary/Keyword: jam

Search Result 516, Processing Time 0.023 seconds

Iterative Channel Estimation Algorithm for Anti-jamming in MIMO Communication Systems (MIMO 통신 시스템에서 항재밍을 위한 반복적인 채널 추정 알고리즘)

  • Jung, Jun Hee;Hwang, Yu Min;Cha, Kyung Hyun;Lee, Jae Seang;Shin, Yoan;Kim, Jin Young
    • Journal of Satellite, Information and Communications
    • /
    • v.11 no.3
    • /
    • pp.32-36
    • /
    • 2016
  • In wireless communication systems, jamming attack is a critical threat. Especially, reactive jamming can jam when the sender and receiver are communicating, which can maximize the attack efficiency of jamming. In this paper, we use the property of multi-input multi-output (MIMO) technology to achieve jamming resilient orthogonal frequency-division multiplexing (OFDM) communications. In particular, we use MIMO interference cancellation to remove the jamming signals strategically. We first investigate the reactive jamming attack model and their impacts on the MIMO-OFDM systems. We then present an iterative channel estimation algorithm that exploits MIMO interference cancellation. Our simulations show various anti-jamming methods and demonstrate the efficiency of our proposed algorithm under the reactive jamming attack.

Relationship between Hospital Case Mix and Costs and Incomes of Tehran Heart Center

  • Langroudi, Hamed Rahimpour;Kakhani, Mohammad Jamil;Hojabri, Roozbeh
    • Asian Journal of Business Environment
    • /
    • v.7 no.3
    • /
    • pp.17-22
    • /
    • 2017
  • Purpose - Clarifying one of the biggest public Hospital Costs and incomes according to patients' case mix. It leads to prepare financial information about pubic medical tariffs and hospital operational costs. Research design, data, and methodology - This study calculates the costs both, with and without taking into account capital costs. This holds for comparison of hoteling based on case mix in all medical procedures. The checklists were reviewed and filled by reviewing accounting documents of the hospital, warehouse exclusion list, and daily books of laundry and CSR. Data was analyzed descriptively by using Excel. Results - In both cases, the hospital is losing in terms of hoteling. Because the buildings and equipment are new, this loss is not tangible. However, this will be revealed when costs of reconstruction and replacement of equipment. The loss rate per day of hospitalization was 569318 Rials for Coronary Care Unit (CCU), 528171 Rials for Post Intensive Care Unit (Post ICU), 474570 Rials for ICU, 233183 Rials for Post CCU and 204803 for Surgical ward. Conclusions - Income of hoteling was lower than its costs. ANOVA showed a strong relationship between case mix and hospital costs as well as case mix and its income. This suggests that optimal case mix can minimize the costs and maximize income.

A Study on the Method and Planning Characteristics of Environment-friendly Skyscraper - Focused on the Analysis of Environment-friendly Skyscraper in other countries - (친환경 초고층 건축 계획 특성 및 기법에 관한 연구 - 해외 친환경 초고층 건축 분석을 중심으로 -)

  • Kim, Ja Kyung
    • KIEAE Journal
    • /
    • v.8 no.3
    • /
    • pp.27-36
    • /
    • 2008
  • Urban architecture density is getting higher, and this trend is expected to continue in the future. Therefore, skyscrapers are being brought into relief as future alternative architecture beyond symbolic meaning in the aspect of demand and supply of urban space. However, skyscrapers which were newly built have many problems such as consumption of enormous amounts of energy, destruction of natural environment, and traffic jam. For this reason, environment-friendly skyscrapers based on the concept such as Green Building and Green Skyscraper started to be built around the world. However, plans or evaluation standards, which take account of the environment-friendly aspect of skyscrapers, leave much to be desired. And especially it is hard to find environment-friendly skyscrapers. Therefore, this study aims to establish the concept of environment-friendly skyscrapers that has not properly been defined, and to find realistic planning methods and practical alternatives through the analysis of the works that have brilliant ideas about environment-friendly architectural method. From the perspective of architectural planning, we did case analysis focused on site planning, form planning, elevation and floor planning, and tried to give useful ideas for high-rise architectural planning in Korea by finding practical solution focused on the active use of natural energy, saving resources, the reduction of wastes, natural architectural environment design and natural friendly system from the view of environment-friendly technological analysis.

A Study on Digital Information Hiding Technique using Random Sequence and Hadamard Matrix (랜덤시퀀스와 Hadamard 행렬을 이용한 디지털 정보은폐 기술에 관한 연구)

  • 김장환;김규태;김은수
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.24 no.9A
    • /
    • pp.1339-1345
    • /
    • 1999
  • In this paper we propose the digital information hiding technique by which we use the combination of random sequence and Hadamard matrix to hide multiple information. The prior work used only one random sequence multiplied by information signal to lower the energy level of information signal and thus it is difficult for a third party to detect the information signal or jam it. But because we have to use the orthogonal code for hiding key in order to hide multiple information in the same digital image, only the use of random sequence that are not uncorrelated has some problems in the information hiding scheme. Thus we present a new information hiding scheme that can be used in hiding multiple information by the use of random sequence that spreads the energy level of the data to be hidden and Hadamard matrix that makes the random sequence uncorrelated.

  • PDF

An In-Tunnel Traffic Accident Detection Algorithm using CCTV Image Processing (CCTV 영상처리를 이용한 터널 내 사고감지 알고리즘)

  • Baek, JungHee;Min, Joonyoung;Namkoong, Seong;Yoon, SeokHwan
    • KIPS Transactions on Software and Data Engineering
    • /
    • v.4 no.2
    • /
    • pp.83-90
    • /
    • 2015
  • Almost of current Automatic Incident Detection(AID) algorithms involve the vulnerability that detects the traffic accident in open road or in tunnel as the traffic jam not as the traffic accident. This paper proposes the improved accident detection algorithm to enhance the detection probability based on accident detection algorithms applied in open roads. The improved accident detection algorithm provides the preliminary judgment of potential accident by detecting the stopped object by Gaussian Mixture Model. Afterwards, it measures the detection area is divided into blocks so that the occupancy rate can be determined for each block. All experimental results of applying the new algorithm on a real incident was detected image without error.

Polymelia with two extra forelimbs at the regions of neck in Korean native cow (한우암소의 목부위에 2개의 여분의 전지가 부착된 과다사지)

  • Kim, Chong-sup;Lee, Jong-hwan;Kim, Eun-hee;Chung, Kyung-tae;Kim, Jam-hoan
    • Korean Journal of Veterinary Research
    • /
    • v.35 no.4
    • /
    • pp.643-649
    • /
    • 1995
  • An abnormal Korean native cow of six years old with extra legs was observed macroscopically and radiographically. The results were summarized as follows; 1. External features included two normal forelimbs and hindlimbs, and two extra forelimbs which were underdeveloped. The extra forelimbs of different length attached laterally to the cranial regions of neck on right scapula. 2. The large extra forelimb had scapular meromelia. It consisted of underdeveloped humerus, antebrachial skeleton, several carpal bones, metacapal bone(MC3+4) and two digitis with each pairs of hoof and a rudimentary hoof of dewclaw. 3. The small extra forelimb had scapular and antebrachial meromelia. It consisted of underdeveloped metacarpal and carpal bone, severely deformed humerus, fused carpal bones, and two digitis with two hooves, and a rudimentary hoof of dewclaw. 4. The dermoid cyst was observed between the large and small extra forelimbs.

  • PDF

A Study on the Environment-friendly Quality Evaluation of High-rise Residential Architecture in Korea by Environment-friendly Certification (친환경 인증 제도를 통한 국내 초고층 주거건축의 친환경성 평가 연구)

  • Kim, Ja Kyung
    • KIEAE Journal
    • /
    • v.8 no.2
    • /
    • pp.31-40
    • /
    • 2008
  • As horizontal expansion of a city reaches the uppermost limit, on the ground of perpendicular expansion and efficiency of land use, skyscrapers go on increasing in number. However, skyscrapers which were newly built in Korea have many problems such as consumption of enormous amounts of energy, destruction of natural environment, and traffic jam. And from now on, environment-friendly development of skyscraper is urgently needed. Therefore, in this study, we tried to find the planning elements and estimation indexes to improve the environment-friendly quality of high-rise residential architecture by investigating environment-friendly skyscraper certification in Korea and the other countries. For that reason, we investigated the application ratios of 10 cases in Korea. And the results showed that the application ratios of environment-friendly estimation indexes were lower than 50% and the environment-friendly quality of skyscrapers in Korea was generally low. Therefore, based on these planning elements and estimation indexes, we tried to establish the guideline of improvement direction for environment-friendly development of high-rise residential architecture in Korea.

Multi-Object Tracking Algorithm for Vehicle Detection (차량 검출을 위한 다중객체추적 알고리즘)

  • Lee, Geun-Hoo;Kim, Gyu-Yeong;Park, Hong-Min;Park, Jang-Sik;Kim, Hyun-Tae;Yu, Yun-Sik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2011.05a
    • /
    • pp.816-819
    • /
    • 2011
  • The image recognition system using CCTV camera has been introduced to minimize not only loss of life and property but also traffic jam in the tunnel. In this paper, multi-object detection algorithm is proposed to track multi vehicles. The proposed algorithm is to detect multi cars based on Adaboost and to track multi vehicles to use template matching. As results of simulations, it is shown that proposed algorithm is useful for tracking multi vehicles.

  • PDF

Genetic Variations of Aspergillus fumigatus Clinical Isolates from Korea

  • Kim, Sunghyun;Ma, Pan-Gon;Park, Young-Seok;Yu, Young-Bin;Hwang, Kyu Jam;Kim, Young Kwon
    • Biomedical Science Letters
    • /
    • v.23 no.3
    • /
    • pp.223-229
    • /
    • 2017
  • Fungal infections by human pathogenic fungi are increasing globally in elderly, children and immune suppressed or deficient patients. Aspergillus fumigatus is one of the well-known pathogenic fungi and causes aspergilloses in human world widely. However, current identification and classification methods based on its phenotypic characteristics still have limitations. Therefore, currently, molecular biological tools using their DNA sequences are used for genotype identification and classification. In the present study, in order to analyze genetic variations of A. fumigatus clinical isolates, a total of six housekeeping genes were amplified by PCR using specific primer pairs and multi-locus sequence typing (MLST) assay. Results from phylogenetic tree analysis showed that most A. fumigatus strains (88.9%) from respiratory specimens were classified into cluster A and B, and approximately half of A. fumigatus strains (46%) from non-respiratory specimens were classified into cluster C and D. Although the sample size was limited, genetic characteristics of A. fumigatus clinical isolates according to their origins were very similar and well-correlated with other clinical data.

Purification and Characterization of a Collagenase from the Mackerel, Scomber japonicus

  • Park, Pyo-Jam;Lee, Sang-Hoon;Byun, Hee-Guk;Kim, Soo-Hyun;Kim, Se-Kwon
    • BMB Reports
    • /
    • v.35 no.6
    • /
    • pp.576-582
    • /
    • 2002
  • Collagenase from the internal organs of a mackerel was purified using acetone precipitation, ion-exchange chromatography on a DEAE-Sephadex A-50, gel filtration chromatography on a Sephadex G-100, ion-exchange chromatography on DEAE-Sephacel, and gel filtration chromatography on a Sephadex G-75 column. The molecular mass of the purified enzyme was estimated to be 14.8 kDa by gel filtration and SDS-PAGE. The purification and yield were 39.5-fold and 0.1% when compared to those in the starting-crude extract. The optimum pH and temperature for the enzyme activity were around pH 7.5 and $55^{\circ}C$, respectively. The $K_m$ and $V_{max}$ of the enzyme for collagen Type I were approximately 1.1 mM and 2,343 U, respectively. The purified enzyme was strongly inhibited by $Hg^{2+}$, $Zn^{2+}$, PMSF, TLCK, and the soybean-trypsin inhibitor.