• Title/Summary/Keyword: Reliable communication

Search Result 1,140, Processing Time 0.028 seconds

A Study on 3D RTLS at Port Container Yards Using the Extended Kalman Filter

  • Kim, Joeng-Hoon;Lee, Hyun-Woo;Kwon, Soon-Ryang
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.7 no.4
    • /
    • pp.228-235
    • /
    • 2007
  • The main purpose of this paper is to manage the container property effectively at the container yard by applying the RTLS technology to the field of port logistics. Yet, many kinds of noises happen to be inputted with the distance value(between the reader and the tag) which is to be inputted into the location identification algorithm, which makes the distance value jumped due to the system noise of the ultrasonic sensor module and the measurement noise. The Kalman Filter is widely used to prevent this jump occurrence; the noises are eliminated by using the EKF(Extended Kalman Filter) while considering that the distance information of the ultrasonic sensor is non-linear. Also, the 3D RTLS system at the port container yard suggested in this research is designed not to be interrupted for its ultrasonic transmission by positioning the antenna at the front of each sector of the container where the active tags are installed. We positioned the readers, which function as antennas for location identification, to four places randomly in the absolute coordinate and let the positions of the active tags identified by using the distance data delivered from the active tags. For the location identification algorithm used in this paper, the triangulation measurement that is most used in general is applied and newly reorganized to calculate the position of the container. In the first experiment, we dealt with the error resulting in the angle and the distance of the ultrasonic sensor module, which is the most important in the hardware performance; in the second, we evaluated the performance of the location identification algorithm, which is the most important in the software performance, and tested the noise cancellation effects for the EKF. According to the experiment result, the ultrasonic sensor showed an average of 3 to 5cm error up to $45^{\circ}$ in case of $60^{\circ}$ or more, non-reliable linear distances were obtained. In addition, the evaluation of the algorithm performance showed an average of $4^{\circ}{\sim}5^{\circ}$ error due to the error of the linear distance-this error is negligible for most container location identifications. Lastly, the experiment results of noise cancellation and jump preservation by using the EKF showed that noises were removed in the distance information which was entered from the input of the ultrasonic sensor and as a result, only signal was extracted; thus, jumps were able to be removed and the exact distance information between the ultrasonic sensors could be obtained.

The Bethedsa System 2001 Workshop Report (The Bethesda System 2001의 최신지견)

  • Hong, Eun-Kyung;Nam, Jong-Hee;Park, Moon-Hyang
    • The Korean Journal of Cytopathology
    • /
    • v.12 no.1
    • /
    • pp.1-15
    • /
    • 2001
  • The Bethesda System (TBS) was first developed in 1988 for the need to enhance the communication of the cytopathologic findings to the referring physician in unambiguous diagnostic terms. The terminology used in this reporting system should reflect current understanding of the pathogenesis of cervical/vaginal disease so the framework of the reporting system should be flexible enough to accommodate advances in medicine including virology, molecular biology, and pathology. Three years after the Introduction of TBS, the second Bethesda workshop was held to set or amend diagnostic criteria for each categories of TBS. TBS 1991 is now widely used. The third Bethesda workshop, The Bethesda System 2001 Workshop, was held in National Cancer institute Bethesda, Maryland from April 30 to May 2, 2001. Again, the goals of this workshop were to promote effective communication and to clarify in reporting cervical cytopathology results to clinicians and to provide with the information to make appropriate decisions about diagnosis and treatment. Nine forum groups were made and there were Web-based bulletin board discussions between October, 2000 and the first week of April, 2001. On the basis of bulletin board comments and discussions, the forum moderators recommended revised terminologies in the Workshop. Hot discussions were followed after the presentation by forum moderators during the workshop. Terminologies confusing clinicians and providing no additional informations regarding patient management were deleted in the workshop to clarify the cervicovaginal cytology results. Any informations related to the patient management were encouraged to add. So 'Satisfactory for evaluation but limited by...' of 'Specimen Adequacy' catergory was deleted. Terminology of 'Unsatisfactory' was further specified as 'Specimen rejected' and 'Specimen processed and examined, but unsatisfactory'. Terminologies of 'Benign Cellular Change' and 'Within Normal Limits' were combined and terminology was changed to 'Negative for intraepithelial lesion or malignancy'. In General categorization, category 'Other' was newly inserted and the presence of 'Endometrial cells' in women over 40 years old can be checked. Although the category 'Benign Cellular Change' was deleted, the organisms or reactive changes of this category can be listed in the descriptive diagnoses. Terminologies of ASCUS and AGUS were changed to atypical squamous cell and atypical glandular cell, respectively. Diagnostic term of 'Adenocarcinoma in situ', which is highly reproducible with reliable diagnostic criteria, was newly Inserted. The category of hormonal evaluation was deleted. Criteria for liquid-based specimen were discussed. Reporting by computer-assisted cytology was discussed and terminology for automated review was newly inserted. This is not the final edition of Bethesda 2001. The final document can be prepared before the ASCCP meeting in which Consensus Guidelines for the Management on Cytology Abnormalities and Cervical Precursors will develop in September 2001.

  • PDF

Lazy Garbage Collection of Coordinated Checkpointing Protocol for Avoiding Sympathetic Rollback (동기적 검사점 기법에서 불필요한 복귀를 회피하기 위한 쓰레기 처리 기법)

  • Chung, Kwang-Sik;Yu, Heon-Chang;Lee, Won-Gyu;Lee, Seong-Hoon;Hwang, Chong-Sun
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.29 no.6
    • /
    • pp.331-339
    • /
    • 2002
  • This paper presents a garbage collection protocol for checkpoints and message logs which are staved on the stable storage or volatile storage for fault tolerancy. The previous works of garbage collections in coordinated checkpointing protocol delete all the checkpoints except for the last checkpoints on earth processes. But implemented in top of reliable communication protocol like as TCP/IP, rollback recovery protocol based on only last checkpoints makes sympathetic rollback. We show that the old checkpoints or message logs except for the last checkpoints have to be preserved in order to replay the lost message. And we define the conditions for garbage collection of checkpoints and message logs for lost messages and present the garbage collection algorithm for checkpoints and message logs in coordinated checkpointing protocol. Since the proposed algorithm uses process information for lost message piggybacked with messages, the additional messages for garbage collection is not required The proposed garbage collection algorithm makes 'the lazy garbage collectioneffect', because relying on the piggybacked checked checkpoint information in send/receive message. But 'the lazy garbage collection effect'does not break the consistency of the whole systems.

Network-Adaptive Transport Error Control for Reliable Wireless Media Transmission (신뢰성 있는 무선 미디어 전송을 위한 네트워크 적응형 전송오류 제어)

  • Lee Chul-Ho;Choi Jeong-Yong;Kwon Young-Woo;Kim Jongwon;Shin Jitae;Jeon Dong-San;Kim Jae-Gon
    • Journal of Broadcast Engineering
    • /
    • v.10 no.4 s.29
    • /
    • pp.548-556
    • /
    • 2005
  • In wireless network environments, wireless channels are characterized by time-varying fading and interference conditions, which may lead to burst packet corruptions and delay variation. This can cause severe quality degradation of streaming media. To guarantee successful transmission of media over the hostile wireless networks, where channel conditions are highly fluctuating, a flexible and network-adaptive transport method is required. Thus, we propose a network-adaptive transport error control consisting of packet-level interleaved FEC and delay-constrained ARQ, which acts as an application-level transport method of streaming media to alleviate burst packet losses while adapting to the changing channel condition in wireless networks. The performances of the proposed network-adaptive transport error control, general error control schemes, and hybrid schemes are evaluated by a developed simulator at the transport-level and video quality of streaming media. Simulation results show that the proposed mechanism provides the best overall performance among compared other schemes in terms of the transport-level performance of error control and the performance of video quality for streaming media.

Power Reduction of Multi-Carrier Transmission System by Using Multi-Dimensional Constellation Mappings (효율적 다차원 성상도를 이용한 다중 반송파 전송 시스템의 전력 감소법)

  • Lee, Kyoung-Won;Kim, Jang-Hyun;Kim, Dae-Jin
    • Journal of Broadcast Engineering
    • /
    • v.14 no.6
    • /
    • pp.733-741
    • /
    • 2009
  • The design rule of digital communication systems is the reliable data transmission with high spectral efficiency and minimum allowable power. This paper suggests the method that saves the average power by implementing a multi-dimensional constellation in case of multi-carrier communication system. By using multi-dimensional constellations we can relocate constellation points in the form of a sphere. If we simply convert the two-dimensional QAM modulation into multi-dimensional QAM, constellation points of 2 N dimensional cube form are made up. Relocating outermost constellation points of 2 N dimensional cube form into low energy constellation points, the constellation of the 2 N-dimensional sphere form is made up which decreases power consumption. In this paper, the multi-dimensional constellations of 2 N-dimensional sphere form are designed from 16-QAM to 2,048-QAM, and power reductions are obtained by comparing constellations of 2-dimensional QAMs and multi-dimensional constellations of 2 N-dimensional sphere form. The result shows that the average power consumption of higher dimensional constellations increases, because the more a dimension elevates, the more the relocatable constellation points increase. But, the increment of the average power savings decreases as the a dimension elevates. The transmission of the data by using multi-dimensional constellations of the sphere form is effective to save the average power consumption with little hardware complexity.

Analysis of Recipes for Korean Foods in Web Sites (레시피 관련 웹 사이트 중 한국음식 레시피의 자료 분석 및 검토)

  • Yun, Mi-Ok;Mun, Hyeon-Gyeong
    • Journal of the Korean Dietetic Association
    • /
    • v.10 no.4
    • /
    • pp.390-400
    • /
    • 2004
  • Food and nutrition sites are the major portion of the health information sites. For the point of public health it is very important to secure validity and reliability of information on those web sites. Therefore, in this study we would like to identify problems when acquiring recipes in web sites by analyzing and reviewing recipes in web sites. To investigate Korean food recipes provided in web sites, domestic search engines such as Simmani, Naver, Hanmir, and Empas and foreign search engines such as Yahoo Korea, Lycos and Altabista Korea were used. Searchs were done using 'recipe' and 'Joribeob (cooking method)' from March 20, 2002 to June 20, 2002. Informations in each sites were reviewed and analyzed Results are as follow; When classifying 46sites searched with 'Joribeob' by the information provider, 24sites were individual, 16sites were corporate and 6sites were others. When searching 'recipe', total 12,654recipes were returned. Out of them, individual provided 2,581sites(20.4%), corporate provided 7,249sites(57.3%), and others provided 2,824sites(22.3%). 9,979(78.9%) recipes out of 12,654recipes were proved to be appropriate as Korean food. Classifying recipes by dish group, vegetables 11.7%, soups and hot soups 9.7%, stew and casseroles 8.2%, pan cakes 8.0%, stir fried foods and skewers 7.8%, rice 7.2%, hard boiled food 7.1%, steam 6.4%, noodles and mandu 5.3%, Kimchi 4.5%, fried 4.1%, and porridge 3.7% in order. 21.1% of recipes were not appropriate as Korean food but provided as Korean Food. The proportion of individual as the information provider were higher than that of enterprises. Recipes from enterprises were based on food and nutrient information and more reliable. However, there were some cases that they provided the same amount of ingredients with different calories or provided the same calories with different ingredients. Additionally, depending on sites, they provided different calories even for the same recipe. There were some cases that the calories provided on the site were too high or too low, for the suggested amount of ingredients and serving size. Recipes those provide amount of calories were evaluated using the nutrient analysis program. Calculated calories and provided calories on the Web were compared together. There are difference between two valus. With these results, it may lead misuse of recipe by those who need accuracy in diet such as patients or who are interested in recipe information for academic purposes. These results could be used as basic materials to improve quantity and quality of recipes in the future. Also, to improve the accuracy of recipies for Korean foods in the web sites, there should be some systems to monitor and let internet users know monitoring results.

  • PDF

A Study on the Effects of BSC System Acceptance Factors on the Intention for Continuous Use (BSC 시스템 수용요인이 지속적 사용의도에 미치는 영향에 관한 연구)

  • Kwon, Oh-Jun;Seo, Hyun-Sik;Oh, Jay-In
    • Asia pacific journal of information systems
    • /
    • v.19 no.3
    • /
    • pp.151-179
    • /
    • 2009
  • The purpose of this study is to make an empirical analysis on the factors affecting the intention for the continuous use of the BSC system, which has been recently spread in the public sector. Because the object of acceptance is the performance management system based on BSC (Balanced Scorecard) implemented in the form of information systems, this study proposes a research model by applying TAM (Technology Acceptance Model). Independent variables are factors affecting the acceptance of BSC system such as training, communication, IS support, CEO support and personal innovativeness, and we examine their effects on the dependent variable, namely, intention on continuous use via mediating variables: perceived usefulness and perceived ease of use. A questionnaire survey was conducted with public institutions(firms) that had introduced and were operating the BSC system; 264 valid questionnaires are adopted. Collected data are analyzed using SPSS 16.0 and AMOS 7.0. Results of reliability test show that all analyzed data are reliable. In validity test, one item regarding communication was excluded; 9 latent variables and 34 observed variables are used in the final analysis. Based on the results of the hypothesis test through path analysis using a structural equation model, 10 out of 16 hypotheses are accepted. Factors affecting perceived usefulness are training and IS(Information System) support. The analysis results indicate that perceived ease of use is mainly affected by IS support, CEO support, and personal innovativeness among the factors related to the acceptance of the BSC system. This suggests that, contrary to the expectation that the BSC system may be used without difficulty, the management's active support is required in order to attain expected improvement in productivity and work efficiency. This was also pointed out in case studies on the construction of the BSC system in public sectors. On the other hand, perceived ease of use is found to affect perceived usefulness. This supports the results of previous researches on TAM. Perceived ease of use and perceived usefulness are found to affect the attitude towards the use of the system. The intention on continuous use is affected more by perceived usefulness than by the attitude towards the use of system. This result supports the results of previous researches on TAM, showing that the BSC system is utilized substantially in worksites. This study is considered meaningful in that it was actually performed on users at public institutions(firms) that had introduced the BSC system and that it empirically tested hypotheses on the acceptance of the BSC system by applying TAM to the research model.

A Study on the Development of Intelligent Markup Indicator (IMI) Technology for Underground Facilities Management Using IoT (IoT를 이용한 지하매설물관리용 지능형표지기(IMI) 기술개발에 관한 연구)

  • Kim, Tai-Dal
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.17 no.3
    • /
    • pp.129-136
    • /
    • 2017
  • Geographic Information System The geographic information system (GIS) has been limited to the government and some public sectors. Recently, the market has been diversified by combining with other areas such as mobile and CRM (Customer Relationship Management). The development direction of GIS technology in the 21st century is Web GIS, 3D GIS, mobile GIS, LBS, etc. as general technology for GIS application system development and spatial information service. In this study, we developed a new concept marking nail (a marking nail with built - in intelligent storage memory device) from the function of simple positioning of a marking nail related to a previously used underground item,, Burial depth, pipe thickness, piping material, management agency, contractor, contact, etc.) and store it in DB server, if necessary.Make it available in the right place. Through this research, it is possible to prevent and minimize various accidents caused by irregular excavation works, etc., and to provide information for establishing countermeasures related to sink holes. In order to provide systematic and reliable information on underground burial management, it was proposed to input information conveniently in the field, and the purpose was to reduce the incidence of buried underground pipes absolutely.

A 3.2Gb/s Clock and Data Recovery Circuit without Reference Clock for Serial Data Communication (시리얼 데이터 통신을 위한 기준 클록이 없는 3.2Gb/s 클록 데이터 복원회로)

  • Kim, Kang-Jik;Jung, Ki-Sang;Cho, Seong-Ik
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.46 no.2
    • /
    • pp.72-77
    • /
    • 2009
  • In this paper, a 3.2Gb/s clock and data recovery (CDR) circuit for a high-speed serial data communication without the reference clock is described This CDR circuit consists of 5 parts as Phase and frequency detector(PD and FD), multi-phase Voltage Controlled-Oscillator(VCO), Charge-pumps (CP) and external Loop-Filter(KF). It is adapted the PD and FD, which incorporates a half-rate bang-bang type oversampling PD and a half-rate FD that can improve pull-in range. The VCO consists of four fully differential delay cells with rail-to-rail current bias scheme that can increase the tuning range and tuning linearity. Each delay cell has output buffers as a full-swing generator and a duty-cycle mismatch compensation. This materialized CDR can achieve wide pull-in range without an extra reference clock and it can be also reduced chip area and power consumption effectively because there is no additional Phase Locked- Loop(PLL) for generating reference clock. The CDR circuit was designed for fabrication using 0.18um 1P6M CMOS process and total chip area excepted LF is $1{\times}1mm^2$. The pk-pk jitter of recovered clock is 26ps at 3.2Gb/s input data rate and total power consumes 63mW from 1.8V supply voltage according to simulation results. According to test result, the pk-pk jitter of recovered clock is 55ps at the same input data-rate and the reliable range of input data-rate is about from 2.4Gb/s to 3.4Gb/s.

Smart meter data transmission device and power IT system using LTE and IoT technologies (LTE와 IoT 기술을 이용한 스마트미터 데이터 전송장치와 전력 IT 시스템)

  • Kang, Ki-Beom;Kim, Hong-Su;Jwa, Jeong-Woo;Kim, Ho-Chan;Kang, Min-Jae
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.18 no.10
    • /
    • pp.117-124
    • /
    • 2017
  • A Smart Grid is a system that can efficiently use energy by exchanging real-time information in both directions between a consumer and a power supplier using ICT technology on an existing power network. DR(Demand response) is an arrangement in which electricity users can sell the electricity they save to the electricity market when the price of electricity is high or the power system is crisis. In this study, we developed a power meter data transmission device and power IT system that measure the demand information in real-time using a smart meter and transmit it to a cloud server. The power meter data transmission device developed in this study uses alight sensor connected to a Raspberry Pi 3 to measure the number of blinking lamps on the KEPCO meter per unit of power, in order to provide reliable data without any measurement errors with respect to the KEPCO power data. The power measurement data transmission device uses the standard communication protocol, OpenADR 2.0b. The measured data is transmitted to the power IT system, which consists of the VEN, VTN, and calculation program, via the LTE WiFi communication network and stored in its MySQL DB. The developed power measurement data transmission device issues a power supply instruction and performs a peak reduction DR when a power system crisis occurs. The developed power meter data transmission device has the advantage of allowing the user to adjust it every 1 minute, where as the existing smart metering time is fixed at once every 15 minutes.