• 제목/요약/키워드: P2P Communication

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Dynamic Survivable Routing for Shared Segment Protection

  • Tapolcai, Janos;Ho, Pin-Han
    • Journal of Communications and Networks
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    • 제9권2호
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    • pp.198-209
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    • 2007
  • This paper provides a thorough study on shared segment protection (SSP) for mesh communication networks in the complete routing information scenario, where the integer linear program (ILP) in [1] is extended such that the following two constraints are well addressed: (a) The restoration time constraint for each connection request, and (b) the switching/merging capacity constraint at each node. A novel approach, called SSP algorithm, is developed to reduce the extremely high computation complexity in solving the ILP formulation. Basically, our approach is to derive a good approximation on the parameters in the ILP by referring to the result of solving the corresponding shared path protection (SPP) problem. Thus, the design space can be significantly reduced by eliminating some edges in the graphs. We will show in the simulation that with our approach, the optimality can be achieved in most of the cases. To verify the proposed formulation and investigate the performance impairment in terms of average cost and success rate by the additional two constraints, extensive simulation work has been conducted on three network topologies, in which SPP and shared link protection (SLP) are implemented for comparison. We will demonstrate that the proposed SSP algorithm can effectively and efficiently solve the survivable routing problem with constraints on restoration time and switching/merging capability of each node. The comparison among the three protection types further verifies that SSP can yield significant advantages over SPP and SLP without taking much computation time.

웨이브렛 변환을 이용한 ECG신호의 잡음제거와 특징점 검출 (Noise Reduction and Characteristic Points Detectoin of ECG Signal using Wavelet Transforms)

  • 장두봉;이상민;신태민;이건기
    • 한국정보통신학회논문지
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    • 제2권1호
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    • pp.11-17
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    • 1998
  • ECG신호가 임상적으로 환자의 심장활동에 관련된 여러 정보를 의사에게 제공한다는 점에서 ECG 신호의 검출은 중요한 환자 진단방법의 하나이다. 특히 QRS복합파형, P파, T파 등의 위치와 각파 간의 간격에 의미있는 정보가 담겨져 있어 의공학 분야에서 ECG신호의 특징점 검출에 관련된 여러 연구들이 있어 왔다. 기존의 ECG신호의 특징점 검출 방법은 정상파형의 경우에는 만족할 만한 성능을 보여 주는데 반해 잡음이 혼입된 ECG신호로부터 정상 ECG신호를 분리해 내는데 있어 성능의 한계를 가진다. 본 논문에서는 최근 공학분야에서 그 활용 영역이 확대되고 있는 웨이브렛 변환 기법을 ECG신호의 특징점 검출과 잡음제거에 적용하여, 잡음이 혼입된 ECG신호의 특징점 검출과 정상 파형 복원을 수행하였다.

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전자연동장치를 위한 연동검사시스템의 개발 (Development of Interlocking Inspection Simulator for Electronic Interlocking System)

  • 이재호;황종규;박영수;박귀태
    • 전기학회논문지P
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    • 제53권2호
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    • pp.70-76
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    • 2004
  • The purpose of interlocking system in railway is to prevent the route for a train being set up and its protecting signal cleared if there were already another, conflicting route set up and the protecting signal for that route cleared. Recently, conventional relays circuitry in industrial field is replaced to computer-based control systems according to the advance of computer and communication technology. Therefore, interlocking systems in railway field are rapidly changing from existing relay-based interlocking system to computer-based electronic ones that executes the vital interlocking logic to assure the safety train routes at trackside signaling equipment room using electronic circuits. So it is very important to verify the performance of developed electronic interlocking system by plentiful laboratory testing before actually application in the railway system. However the laboratory testing in the present state of railway signaling is preformed individually by manual, so very much test time and cost are required. To solve these problems, we are developed the simulator for automatic interlocking inspection in this research. This simulator is able to operate on general personal computer and has following beneficial functions : automatic test sheet generation for inspection, automatic inspection execution and et al. The experiments are executed to test the feasibility of the developed simulator the experimental results have good agreements with the anticipated ones.

Using Data Mining Techniques in Building a Model to Determine the Factors Affecting Academic Data for Undergraduate Students

  • Nafie, Faisal Mohammed;Hamed, Abdelmoneim Ali Mohamed
    • International Journal of Computer Science & Network Security
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    • 제21권4호
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    • pp.306-312
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    • 2021
  • The main goal of higher education institutions is to present a high level of quality education to its students. This study uses data mining techniques to extract educational data from cumulative databases and used them to make the right decisions. This paper also aims to find the factors affecting students' academic performance in Majmaah University, KSA, during 2010 - 2017 period. The study utilized a sample of 6,158 students enrolled from two colleges, males and females. The results showed a high percentage of stumbling and dismissed between graduate and regular students where more than 62.5% failed to follow the plan. Only 2% of students scored distinction during their study of all graduated since their grade point average, secondary level, was statistically significant, where p<0.05. Dismissed percentage was higher among males. These results promoted some recommendations in which decision-makers could take them in considerations for better improvement of academic achievements: including of specialized programs to follow-up in regards to stumbling and failure. Utilization of different communication tools are needed to activate academic advisory for dismiss and dropout evaluation.

The Effects of Personality and Attitude on Risky Driving Behavior Among Public van Drivers: Hierarchical Modeling

  • Tanglai, Wirampa;Chen, Ching-Fu;Rattanapan, Cheerawit;Laosee, Orapin
    • Safety and Health at Work
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    • 제13권2호
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    • pp.187-191
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    • 2022
  • Background: Traffic injuries have become a significant public health problem in low- and middle-income countries. Several studies have examined the role of personality and attitude toward traffic safety in predicting driving behaviors in diverse types of drivers. Few studies have investigated risky behavior among public passenger van drivers. This study aims to identify the predictors of self-reported risky driving behavior among public van drivers. Method: A total of 410 public van drivers were interviewed at terminal stations in Bangkok. Hierarchical regression models were applied to determine the effects of demographics, personality traits, and attitude on self-reported risky driving behaviors. Results: The results indicated that drivers with a high education level, more working days, and high scores for normlessness and anger were more likely to report risky driving behaviors (p < 0.05). Conclusion: The personality traits and attitude toward speeding account for aberrant self-reported risky driving behavior in passenger van drivers. This could be another empirical basis for evidence-based road safety interventions in the context of public transport.

요양병원 간호사의 전문직 자아개념과 직무만족 (Professional Self-concept and Job Satisfaction among Nurses Working in Long-term Care Hospitals)

  • 박종현;김세영
    • 한국직업건강간호학회지
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    • 제31권4호
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    • pp.178-186
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    • 2022
  • Purpose: The purpose of this study is to identify the relationship between professional self-concept and job satisfaction of nurses working in long-term care hospitals and to consider strategies to improve these factors. Methods: Data were collected using structured questionnaires given to 135 nurses working at six long-term care hospitals in C City. The data were analyzed with SPSS 23.0 by descriptive statistics, Cronbach's α, t-test, one-way ANOVA, a Scheffé test, and with Pearson's correlation coefficient. Results: The average score for professional self-concept was 2.78 points (out of 4 points), and the average score for job satisfaction was 3.11 points (out of 5 points). Significant differences were found for professional self-concept according to age, marriage status, total work experience, number of patients per nurse, and position, while job satisfaction showed significant differences depending on age and the number of patients in the ward. Professional self-concept and job satisfaction showed a significant positive correlation (r=.46, p<.001). Conclusion: In long-term care hospitals, it is necessary to provide education programs about nursing practice, communication, and leadership to enhance the professional self-concept of nurses. With regard to job satisfaction for nurses, it is imperative to improve the work environment of long-term care hospitals.

Host Cellular Response during Enterohaemorrhagic Escherichia coli Shiga Toxin Exposure

  • Kyung-Soo, Lee;Seo Young, Park;Moo-Seung, Lee
    • 한국미생물·생명공학회지
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    • 제50권4호
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    • pp.441-456
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    • 2022
  • Shiga toxins (Stxs) are major virulence factors from the enterohemorrhagic Escherichia coli (EHEC), a subset of Stx-producing Escherichia coli. Stxs are multi-functional, ribosome-inactivating proteins that underpin the development of hemolytic uremic syndrome (HUS) and central nervous system (CNS) damage. Currently, therapeutic options for the treatment of diseases caused by Stxs are limited and unsatisfactory. Furthermore, the pathophysiological mechanisms underpinning toxin-induced inflammation remain unclear. Numerous works have demonstrated that the various host ribotoxic stress-induced targets including p38 mitogen-activated protein kinase, its downstream substrate Mitogen-activated protein kinase-activated protein kinase 2, and apoptotic signaling via ER-stress sensors are activated in many different susceptible cell types following the regular retrograde transportation of the Stxs, eventually leading to disturbing intercellular communication. Therapeutic options targeting host cellular pathways induced by Stxs may represent a promising strategy for intervention in Stx-mediated acute renal dysfunction, retinal damage, and CNS damage. This review aims at fostering an in-depth understanding of EHEC Stxs-mediated pathogenesis through the toxin-host interactions.

A Study on the Development of Core Competency Diagnostic Tools for Professors at A' University

  • Soo-Min PARK;Tae-Chang RYU
    • 융합경영연구
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    • 제11권4호
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    • pp.31-39
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    • 2023
  • Purpose: This study attempted to systematize a support system that can enhance teaching core competencies by establishing a scale for diagnosing teaching core competencies at University A. Research design, data and methodology : To this end, the first Delphi was conducted With six experts related to university core competency modeling research by extracting factors and designing structured questionnaires through a literature review process that collects and analyzes prior research related to domestic and foreign university teaching competency. The derived questions were diagnosed on 27 professors, and independent sample t-verification and ANOVA were conducted using SPSS 24.0 for analysis by key teaching competency factors. Result: What is the standard suitability of KMO. It was shown as 929 (KMO standard conformity value is close to 1), and Barlett's sphericity verification showed χ2=5773.295, df=1081, p<.It appeared as 001 and confirmed that it was suitable for conducting factor analysis. Conclusions: The core competencies of A University teachers were set based on the educational goals of A University, such as basic teaching competency, creative teaching competency, practical teaching competency, and communication teaching competency. This means that the concept and factors of the core competency of professors are likely to change, and in the end, continuous efforts to upgrade and apply research on core competency of professors are essential to quickly and organically respond to changes in competency required to increase the competitiveness of universities.

간 전이환자에서 최적의 펄스시퀀스에 따른 SPIO 특이성 조영제의 국소병변검출: Case review (Focal Lesion Detection of SPIO-specific agent Compared with Optimized Pulse Sequences in the Hepatic Metastases: Case Review)

  • 구은회
    • 대한디지털의료영상학회논문지
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    • 제14권2호
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    • pp.57-61
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    • 2012
  • To compare the accuracy of breath-hold magnetic resonance imaging sequences to establish the most effective superparamagnetic iron oxide-enhanced sequence for detection of hepatic metastases. A total of 100 patients(50men and 50women, mean age: 60years) with liver disease(including malignant and benign liver lesions) were investigated at 3.0T machine (GE, General Electric Medical System, Excite HD) with 8Ch body coil. Pulse sequence for MR imaging decided to the FS-T2-FSE-RT(TR/TE/Thick./Freq./Phase=12857ms/100ms/7mm/512/384), MGRE(TR/TE/Thick./Freq./Phase=100ms/9.7ms/7mm/384/288), in-out of phase echo(TR/$TE_1$, $TE_2$/Thick./Freq./Phase=140ms/2.4, 5.8ms/7mm/352/300), Images obtained before the injection of SPIO. Six sequences were optimized for lesion detection: FS-T2-FSE-RT, multigradient recalled echo data image(MGRE), T2-weighted MGRE with an 9.7msec echo time. Images were reviewed independently by five blinded observers. The accuracy of each sequence was measured by using picture archiving communication system analysis. All results were correlated with findings at multidectator computed tomography examination. Differences between the mean results of the six observers were measured by using paired student t-test analysis. Postcontrast T2-weighted MGRE sequences were the most accurate and were significantly superior to postcontrast FS-T2-FSE-RT, T2-weighted MGRE, in-out of phase MR sequences(p < .05). For all lesions that were malignant or smaller than 1 cm, respectively, contrast to noise ratio of pre and postcontrast sequences were -1and -0.3 for T2-weighted FSE, 0.53 and 4.5 in-out of phase, 7, 7.08, 5.08, 3.32, 1.7, 1.16, 0.79, 0.68 for GRE with 2.9, 7.5, 12.1, 16.6, 21.2, 25.8, 30.4, 35.0 TE values. Breath-hold various TE precontrast sequences offer improvement in sensitivity compared with fixed multigradient recalled echo sequences alone.

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유아교육기관에서의 급식관리 실태에 대한 교사 및 학부모의 인식 연구 (The Different View Point of Child Education Center Food Service Program between the Parents and the Teachers)

  • 이영미
    • 대한지역사회영양학회지
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    • 제10권5호
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    • pp.654-667
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    • 2005
  • To survey the different view points about food service programs among parents and teachers, 2 types of questionnaires, which consisted of attitude, perception, satisfaction and demand of the food service program in child education centers, were used. The data was collected from 2450 parents and 450 teachers who attended a child education center in 16 provinces, nationwide. SPSS was used for descriptive analysis and ANOVA test and $X^2-test$. The frinding results were as follows. 1. The average serving size of meal (lunch) were 80 meals per day and 167 meals per day at large institutions. Mean cost of snacks was 14,709 won per month and mean costs of lunch were 29,319 won per month. The mean price was not significantly different according to the scale of institution. The numbers of servings of lunch, morning snack and afternoon snack were 5, 3.4 and 3.5 times per week each. $56.4\%$ of the institutions served meals to children in classrooms, but the national/public institutions, which were attending elementary school, served meals in a dining place in the elementary school. 2. Teacher controlled serving portion size of snacks $(79.6\%)$ and lunch $(88.8\%)\;and\;30.1\%$ of teacher did not allow leaving lunch food. The ratio of knowing about preserved meals of the teacher who worked at a small institution was significantly higher than the teacher who worked at large institutions (p<0.01). 3. Between parents and teachers, several different view points about school lunch programs were detected. Most parents and teachers wanted that the school lunch to be fully cooked and served at the child education institution itself, but $12.2\%$ of parents and $14.4\%$ of teachers wanted a catering service. The teachers group preferred 'lunch box from home' and 'home partially prepared lunch' as an ideal meal serving type than the parent groups (p<0.01). And there were significantly different view points about price factors in school meals, teachers group highly answered that operating expenses must be added in meal prices. 4. The teacher groups' priorities of education activities during meal time were a significantly lower score than parents group in overall education activities. Teacher and parent groups pointed out that individual sanitation activities were most important of the education activities during meal time, but promoting good eating habits was the lowest score in both groups. 5. 'Improving taste and food quality' was most urgent in food service at child education centers, but there were significantly different view points between parent groups $(64.5\%)$ and teacher groups $(43.8\%)\;(p<0.05)$. They answered at a lower percent in 'employee qualified person' and 'cost control' point to improve food service, but there were also different opinions between the two groups (p<0.01). 6. As to the matter of the advantages and disadvantages of catering services, two group answered that the advantages of a catering service were 'convenience' and 'to solve facilities and labor problems', disadvantages were 'lower in food freshness' and 'sanitation problems'. There were also several different view pionts in catering services, the parents groups were more anxious about food sanitation than teachers. This study found several different view points about school food services among parents and teachers. To improve food services at child education institutions, there is a need to adjust the differences between the two groups through interactive communication channels and education and to employ dietitians as taking charge of adjusting roles between the two groups.