• Title/Summary/Keyword: address period

Search Result 376, Processing Time 0.022 seconds

Detection of a Radar Signal Using the Periodicity of its Autocorrelation Function (자기 상관 함수의 주기성을 이용한 레이다 신호 검출)

  • Lim, Chang Heon;Kim, Hyung Jung;Kim, Chang Joo
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.41 no.7
    • /
    • pp.732-737
    • /
    • 2016
  • A pulse radar signal exhibits periodic appearance of pulses in time. So it leads to a high correlation between two samples separated in time by multiples of its period. In this paper, we present a spectrum sensing technique for a radar signal which exploits the periodicity of its autocorrelation function and a radar pulse interval estimation scheme in order to address the case that the radar pulse interval is not known a priori. Finally, we evaluate the sensing performance of the proposed scheme through computer simulation and compare its performances with those of energy detection.

Research Trends on Parent-Child Relationships from the Perspective of Nursing (간호학 관점에서의 부모-자녀 관계 연구동향)

  • Kim, Mi-Ran;Park, Young-Hee;Park, Eun-Sook
    • Child Health Nursing Research
    • /
    • v.16 no.4
    • /
    • pp.249-258
    • /
    • 2010
  • Purpose: This study was done to provide a basis for future theory development by analyzing the phenomenon of parent-child relationships based on the 4 areas described by Kim (2000). Methods: A descriptive research design was used to identify research trends in nursing related to the phenomenon of parent-child relationships. Results: Before 1990, the trend in research design was quantitative designs, but since 1990, qualitative research has also been done. Mothers were the most popular research target for these studies followed by mothers and children together. In analyzing the 4 areas outlined by Kim (2000), it was found that most of the research was done on client domain and parents. The research concepts relevant to the essentialistic concept of research target, were 'child rearing', 'breast-feeding' and 'attachment'. For problematic concepts, the concept of 'stress' was continuously dealt with over the period and for the health-care experiential concept, 'adjustment' and 'coping' by parents were the main focus of research. Conclusion: The results show that parent-child relationship research was mainly concentrated on research participants and concepts. In the future, improvements should be made in research development of nursing practice programs and development of theory, to address the complete phenomenon of parent-child relationships.

Modified Ramp-Reset Waveform Robust for Variable Panel Temperature and its Discharge Characteristics

  • Jang, Soo-Kwang;Tae, Heung-Sik;Kim, Soon-Bae;Jung, Eun-Young;Suh, Kwang-Jong;Ahn, Jung-Chull;Heo, Eun-Gi;Lee, Byung-Hak;Lee, Kwang-Sik
    • Journal of Information Display
    • /
    • v.7 no.1
    • /
    • pp.25-29
    • /
    • 2006
  • By the voltage threshold (Vt) close-curve measurement method, the changes in the discharge characteristics such as a firing voltage and IR emission among the three electrodes were examined relative to the low or high panel temperature ranging from -10 to $80^{\circ}$. The variation in the panel temperature was found significantly influence the surface discharge between the MgO surfaces rather than the plate gap discharge between the MgO and phosphor layers. Based on this experimental observation, a modified reset waveform that alleviates the surface discharge during a ramp-up and -down period was deeloped. By adopting the proposed reset waveform, a stable address discharge could be obtained irrespective of the panel temperature variation.

RESONANCE FREQUENCY ANALYSIS OF IMPLANTS WITH ANODIZED SURFACE OXIDES

  • Choi Jeong-Won;Heo Seong-Joo;Chang Ik-Tae;Koak Jai-Young;Han Jong-Hyun;Kim Yong-Sik;Lee Seok-Hyung;Yim Soon-Ho
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.42 no.3
    • /
    • pp.294-300
    • /
    • 2004
  • The present experimental study was designed to address two issues. The first was to investigate whether oxidation voltage of titanium implants influenced bone tissue responses after an in vivo implantation. The second aim was to investigate secondary stability change after 1 to 3months period. Screw-shaped implants with a wide range of oxide properties were prepared by electrochemical oxidation methods, where the oxide thickness varied in the range of $3-15{\mu}m$. The micro structure revealed pore sizes of $1-3{\mu}m$, the crystal structures of the titanium oxide were amorphous, anatase and a mixture of anatase and rutile type. Bone tissue responses were evaluated by resonance frequency measurements that were undertaken 1 to 3months after insertion in the rabbit tibia. It was concluded that no statistical difference of RFA values was found between the groups, RFA gains after Imonth and 3months were calculated.

Block-Time of Arrival/Leaving Estimation to Enhance Local Spectrum Sensing under the Practical Traffic of Primary User

  • Tran, Truc Thanh;Kong, Hyung Yun
    • Journal of Communications and Networks
    • /
    • v.15 no.5
    • /
    • pp.514-526
    • /
    • 2013
  • With a long sensing period, the inter-frame spectrum sensing in IEEE 802.22 standard is vulnerable to the effect of the traffic of the primary user (PU). In this article, we address the two degrading factors that affect the inter-frame sensing performance with respect to the random arrival/leaving of the PU traffic. They are the noise-only samples under the random arrival traffic, and the PU-signal-contained samples under the random leaving traffic. We propose the model in which the intra-frame sensing cooperates with the inter-frame one, and the inter-frame sensing uses the time-of-arrival (ToA), and time-of-leave (ToL) detectors to reduce the two degrading factors in the inter-frame sensing time. These ToA and ToL detectors are used to search for the sample which contains either the ToA or ToL of the PU traffic, respectively, which allows the partial cancelation of the unnecessary samples. At the final stage, the remaining samples are input into a primary user detector, which is based on the energy detection scheme, to determine the status of PU traffic in the inter-frame sensing time. The analysis and the simulation results show that the proposed scheme enhances the spectrum-sensing performance compared to the conventional counter-part.

Current concepts of Laser dentistry (임상가를 위한 특집2 - Current concepts of Laser dentistry)

  • Eun, Hee-Jong
    • The Journal of the Korean dental association
    • /
    • v.49 no.11
    • /
    • pp.670-678
    • /
    • 2011
  • Various sorts of dental devices for the dental treatment have been introduced and adopted during past several years. Dental Laser, among all devices, seems to be possible for applying to over the whole treatments and widely employed. Furthermore, this article is to introduce that Dental Laser is intended to care patients secured with the effectual treatment against Conventional procedures based upon its studies. The advantages of Dental Laser treatment-along with LLLT (Low Level Laser Therapy) effect, biostimulation effect, and minimal invasive technique - make the patients reduce their fear of the operation, lighten the inconvenience of post operation, and shorten the treatment period. In particular, it is worth considering that the use of laser-assisted therapies is associated with a marked reduction in the use of analgesics and anti-inflammatory medications compared with conventional procedures. This article is to state advantages and differences of Dental Laser treatment compared with Conventional procedures, and to emphasize to become well-acquainted with the precautions for safety and effective Dental Laser treatment. In case of operating Dental Laser with lack of the instructions, it will cause the unpredicted fatal results; therefore this treatment requires special care in its operation. Henceforward, it is anticipated that infinite treatment protocols will be introduced by applying Dental Laser, and this is to address the utilization of Dental Laser.

A Study on Discharge Characteristics of the PDP Packaged with In-situ Vacuum Sealing with the MgO Protective Layer Deposited by Optimal Evaporation Rate (최적 증착 속도로 형성된 MgO를 갖는 인-라인 진공 실장된 플라즈마 디스플레이 패널의 방전 특성에 관한 연구)

  • Li, Zhao-Hui;Cho, Eou-Sik;Kwon, Sang-Jik
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.21 no.10
    • /
    • pp.916-922
    • /
    • 2008
  • AC PDP with MgO protective layer coated with the optimum evaporation rate of $5{\AA}/s$ can generate more enhanced efficiency through the vacuum in-line sealing process. However, the optimized process conditions still require the optimum driving scheme on the ramp-up and ramp-down slope of the reset waveform for enhancing the efficiency. In this paper, for the in-situ vacuum sealed PDP with the optimum evaporation rate of MgO protective layer, the address delay time was investigated with various slopes of ramp waveform during a reset ramp-up and ramp-down period. In this study, the minimum statistical delay time was obtained at the ramp-up rate of $6.0 V/{\mu}s$ and the ramp-down rate of $0.7 V/{\mu}s$ of the reset waveform.

Structural Factors of the Middle East Respiratory Syndrome Coronavirus Outbreak as a Public Health Crisis in Korea and Future Response Strategies

  • Kim, Dong-Hyun
    • Journal of Preventive Medicine and Public Health
    • /
    • v.48 no.6
    • /
    • pp.265-270
    • /
    • 2015
  • The recent Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak has originated from a failure in the national quarantine system in the Republic of Korea as most basic role of protecting the safety and lives of its citizens. Furthermore, a number of the Korean healthcare system's weaknesses seem to have been completely exposed. The MERS-CoV outbreak can be considered a typical public health crisis in that the public was not only greatly terrorized by the actual fear of the disease, but also experienced a great impact to their daily lives, all in a short period of time. Preparedness for and an appropriate response to a public health crisis require comprehensive systematic public healthcare measures to address risks comprehensively with an all-hazards approach. Consequently, discussion regarding establishment of post-MERS-CoV improvement measures must focus on the total reform of the national quarantine system and strengthening of the public health infrastructure. In addition, the Korea Centers for Disease Control and Prevention must implement specific strategies of action including taking on the role of "control tower" in a public health emergency, training of Field Epidemic Intelligence Service officers, establishment of collaborative governance between central and local governments for infection prevention and control, strengthening the roles and capabilities of community-based public hospitals, and development of nationwide crisis communication methods.

The development of LCC evaluation tool on Excel Base (엑셀 기반의 LCC 평가도구 개발)

  • Chung, Kwang-Woo;Kim, Chul-Su;An, Joon-Yong;Chung, Jong-Duk
    • Proceedings of the KSR Conference
    • /
    • 2010.06a
    • /
    • pp.1630-1641
    • /
    • 2010
  • LCC can be defined as "the sum of present values of investment costs, capital costs, installation costs, energy costs, operating costs, maintenance costs, and disposal costs over the life-time of the project, product, or measure." LCCA involves estimating the costs and timing associated with each alternative over a selected analysis period and conversion of those costs to economically comparable values considering the time-value of money. The several Excel-Based LCC tools found on the internet are described in this paper. Also, This paper performed an analysis of the existing LCC commercial tools, assessing various aspects of each program. The goal was to evaluate the best features of each tool and to identify the requirements for LCC evaluation of Urban Transit Vehicle. The LCC tools are developed to address problems in many different areas and a tool developed and structured for one area cannot generally be used in another area. No general LCC tool exists and if one is needed for Urban Transit Vehicle it has to be developed by the project. Since a full LCC can be very complex it is likely that this Excel-Based LCC tool should be a small and simple tool for quick cost estimates. This paper presents a LCC tool consisting of eight excel sheets, which are "Project", "CBS", "PBS", "PM", "CM", "Others", "LCC Result" and "Diagram".

  • PDF

Performance Evaluation of MTF Peak Detection Methods by a Statistical Analysis for Phone Camera Modules

  • Kwon, Jong-Hoon;Rhee, Hyug-Gyo;Ghim, Young-Sik;Lee, Yun-Woo
    • Journal of the Optical Society of Korea
    • /
    • v.20 no.1
    • /
    • pp.150-155
    • /
    • 2016
  • To evaluate the autofocusing performance of recent mobile phone cameras, it is necessary to determine the peak position of the center field MTF (Modulation Transfer Function), -known as the through focus MTF- of the module. However, the MTF peak position found by conventional methods deviates from the ideal position due to the focus scanning resolution of mobile phone cameras. This inaccurate peak position results in false judgements of the optical performance, leading to yield losses or customer complaints. An increase in the focus scanning resolution can address this problem, but the manufacturing UPH (Unit per Hour) level will also unfortunately increase as well, resulting in a loss of manufacturing capabilities. In this paper, several fitting models are studied to find an accurate MTF peak position within a short period of time. With an analysis of a large amount of manufacturing data, it is demonstrated that the fitting methods can reduce false judgements and simultaneously increase the capabilities of the manufacturing system.