• Title/Summary/Keyword: frequency-response

Search Result 5,567, Processing Time 0.044 seconds

Preference of Cohousing according to Sense of Community in Housing Life (주생활 공동체 의식에 따른 코하우징 선호도)

  • Kwak, Yu-Mi;Choi, Jung-Sin;Kwak, In-Sook
    • Journal of the Korean housing association
    • /
    • v.18 no.4
    • /
    • pp.37-48
    • /
    • 2007
  • Purpose of this study is to investigate influence on preference of cohousing (eg. intention to spread and intention to move in cohousing) according to sense of community, especially in housing life by married people residing in Seoul and its outskirts. Research method used for this study was a social survey. Respondents were 214 people by accidential sampling. The collected data were analyzed by SPSS 12.0 program using frequency, mean, average, T-test, one-way Anova, Duncan's Multiple Range test and Chi-square test. Findings of this study were as follows. Most respondents took part in interactive activities with colleagues from the same occupation. They Focused on the issues about health, leisure and hobby. The respondents mainly wanted to have interaction for changing recycling materials and education programs for children and juveniles. Degree of ideal relationships with neighbors, they think, were greeting and chatting as well as communication about issues on child-care, education for children, offense-prevention and safety. Although respondents were interested in community life and in interaction with their neighbors, they did not build up communal society due to lack of a sense of belonging in their living areas. While respondents showed positive response about preference of cohousing, there were difference between intention to spread of cohousing and intention to move in cohousing. As a result of this study, the stronger sense of community in housing life meant the more interests in thoughts to spread and to move in cohousing. Therefore, in order to increase sense of community in cohousing, the plan of various communication programs that enables frequent interaction among neighbors is needed. Also, in order to spread cohousing in Korea, promotion of cohousing community and cognitions about it are the most needed.

A Study on the Interest of the Eyes Applying Gazing Phenomena - Based on an Eye-tracking Experiment Carried with a Facade as a Medium - (주시현상을 적용한 시선의 관심도 연구 - 파사드를 매개로 한 아이트래킹 실험 중심으로 -)

  • Yeo, Mi;Lee, Chang No
    • Korean Institute of Interior Design Journal
    • /
    • v.23 no.1
    • /
    • pp.122-131
    • /
    • 2014
  • This study aimed to conduct an eye-tracking experiment carried with facade images as a medium and to do research on 'the interest of the eyes' resulted from people's gazing phenomena. This study secured gazing data which appeared according to visual response and analyzed gazing phenomena to find the basic theory of 'the interest of the eyes' as a methodological role, which consumer interest and attention could be grafted when a plan and a design for space design was made. Data terms used in eye-tracking backgrounds and the movement of the eyes were investigated in literature review. Twenty (20) facade images were selected through a case study to get experimental stimuli for the related experiment. Thirty (30) subjects (men and women) suitable for the experiment were recruited to conduct an eye-tracking experiment. After the experiment, five (5) areas were set up in the facade image to identify the focus level of interest and attention. The level of interest and focus was connected to the interest of the eyes. The analysis to study the interest of the eyes was based on nine (9) items such as sequence, entry time, dwell time, hit ratio, revisits, revisitors, average fixation, first fixation and fixation count. Through gaze analysis, the following conclusion was drawn about the 'interest level of sight' for gaze frequency. The interest level can be interpreted to be higher for faster sequence, shorter entry time, longer all fixation(ms) for dwell time, faster all saccade(%), higher hit ratio, more revisits, more revisitors, longer average fixation, faster and longer first fixation, and more fixation count, and the person can be said to have felt interest faster and/or more.

Performance Modeling of an EPC Information Service System

  • Kim, So-Jung;Kang, Yong-Shin;Son, Kyung-Won;Lee, Yong-Han;Rhee, Jong-Tae;Hong, Sung-Jo
    • Industrial Engineering and Management Systems
    • /
    • v.9 no.3
    • /
    • pp.285-293
    • /
    • 2010
  • To obtain visible and traceable information from the supply chain, HW/SW standards for the EPC global network, which process electronic product code (EPC) data read from Radio frequency identification (RFID) tags, are regarded as the de facto industry standard. Supply chain participants install information service systems and provide logistics information to partners by following the EPCglobal architecture framework. Although quality of service (QoS) is essential for providing dependable and scalable services as pointed out by Auto-ID Lab, only a few models for the performance analysis of QoS-related work have been developed in the context of EPC information service systems. Specifically, doing so allows alternative design choices to be tested in an easy and cost-effective manner and can highlight potential performance problems in designs long before any construction costs are incurred. Thus, in this study we construct a model of an EPC information service system for the purposes of performance analysis and designing a dependable system. We also develop a set of building blocks for analytical performance models. To illustrate how the model works, we determine the characteristics of an EPC information service system and then select a combination of these proven modeling concepts. We construct a performance model that considers the response time and shows how to derive meaningful performance values. Finally, we compare the analytical results to measurements of the EPC information service system.

New Control Method for Power Decoupling of Electrolytic Capacitor-less Photovoltaic Micro-Inverter with Primary Side Regulation

  • Irfan, Mohammad Sameer;Shin, Jong-Hyun;Park, Joung-Hu
    • Journal of Electrical Engineering and Technology
    • /
    • v.13 no.2
    • /
    • pp.677-687
    • /
    • 2018
  • This paper presents a novel power decoupling control scheme with the bidirectional buck-boost converter for primary-side regulation photovoltaic (PV) micro-inverter. With the proposed power decoupling control scheme, small-capacitance film capacitors are used to overcome the life-span and reliability limitations of the large-capacitance electrolytic capacitors. Then, an improved flyback PV inverter is employed in continuous conduction mode with primary-side regulation for the PV power conditioning. The proposed power-decoupling controller shares the reference for primary side current regulation of the flyback PV inverter. The decoupling controller shapes the input current of the bidirectional buck-boost converter. The shared reference eliminates the phase-delay between the input current to the bidirectional buck-boost converter and the double frequency current at the PV primary current. The elimination of the phase-delay in dynamic response enhances the ripple rejection capability of the power decoupling buck-boost converter even with small film capacitor. With proposed power decoupling control scheme, the additional advantage of the primary-side regulation of flyback PV inverter is that there is no need to have an extra current sensor for obtaining the ripplecurrent reference of the decoupling current-controller of the power-decoupling buck-boost converter. Therefore, the proposed power decoupling control scheme is cost-effective as well as the size benefit. A new transient analysis is carried out which includes the source voltage dynamics instead of considering the source voltage as a pure voltage source. For verification of the proposed control scheme, simulation and experimental results are presented.

Development of DC-DC Converter for Ancillary Power Supply in Hybrid Electric Vehicle (하이브리드 자동차 보조전원 공급용 DC-DC 컨버터 개발)

  • Kim, Jong-Cheol;Choi, Deok-Kwan;Park, Hae-Woo
    • Proceedings of the KIPE Conference
    • /
    • 2005.07a
    • /
    • pp.261-265
    • /
    • 2005
  • This paper describes the DC-DC Converter for Ancillary Power Supply in Hybrid Electric Vehicle. DC-DC Converter is used for charging 12V auxiliary battery supplying electric power to head ramp, audio, ECU etc in automobiles. used DC-DC Converter Topology is PS-ZVS FB(Phase Shifted Zero Voltage Switching Full-Bridge) to reduce switching loss and EMI noise induced by high frequency operating condition. And For easy compensation and stable system response characteristic, current mode control method including slope compensation is employed. Constant current / constant voltage charging control method guarantee stable electric charging of auxiliary battery. Simulation toll PSIM6.0 is used for initial circuit parameter settings and H/W debuging. Thermal problems of Switching components in DC-DC Converter is improved by using Thermo Tracer.

  • PDF

Super-Resolution Algorithm by Motion Estimation with Sub-Pixel Accuracy using 6-Tap FIR Filter (6-Tap FIR 필터를 이용한 부화소 단위 움직임 추정을 통한 초해상도 기법)

  • Kwon, Soon-Chan;Yoo, Ji-Sang
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.37 no.6A
    • /
    • pp.464-472
    • /
    • 2012
  • In this paper, we propose a new super-resolution algorithm that uses successive frames by applying the block matching motion estimation algorithm. Usually, single frame super-resolution algorithms are based on probability or discrete wavelet transform (DWT) approach to extract high-frequency components of the input image, but only limited information is available for these algorithms. To solve this problem, various multiple-frame based super-resolution algorithms are proposed. The accuracy of registration between frames is a very important factor for the good performance of an algorithm. We therefore propose an algorithm using 6-Tap FIR filter to increase the accuracy of the image registration with sub-pixel unit. Proposed algorithm shows better performance than other conventional interpolation based algorithms such as nearest neighborhood, bi-linear and bi-cubic methods and results in about the same image quality as DWT based super-resolution algorithm.

Widely-Linear Beamforming and RF Impairment Suppression in Massive Antenna Arrays

  • Hakkarainen, Aki;Werner, Janis;Dandekar, Kapil R.;Valkama, Mikko
    • Journal of Communications and Networks
    • /
    • v.15 no.4
    • /
    • pp.383-397
    • /
    • 2013
  • In this paper, the sensitivity of massive antenna arrays and digital beamforming to radio frequency (RF) chain in-phase quadrature-phase (I/Q) imbalance is studied and analyzed. The analysis shows that massive antenna arrays are increasingly sensitive to such RF chain imperfections, corrupting heavily the radiation pattern and beamforming capabilities. Motivated by this, novel RF-aware digital beamforming methods are then developed for automatically suppressing the unwanted effects of the RF I/Q imbalance without separate calibration loops in all individual receiver branches. More specifically, the paper covers closed-form analysis for signal processing properties as well as the associated radiation and beamforming properties of massive antenna arrays under both systematic and random RF I/Q imbalances. All analysis and derivations in this paper assume ideal signals to be circular. The well-known minimum variance distortionless response (MVDR) beamformer and a widely-linear (WL) extension of it, called WL-MVDR, are analyzed in detail from the RF imperfection perspective, in terms of interference attenuation and beamsteering. The optimum RF-aware WL-MVDR beamforming solution is formulated and shown to efficiently suppress the RF imperfections. Based on the obtained results, the developed solutions and in particular the RF-aware WL-MVDR method can provide efficient beamsteering and interference suppressing characteristics, despite of the imperfections in the RF circuits. This is seen critical especially in the massive antenna array context where the cost-efficiency of individual RF chains is emphasized.

A Study on Prediction of Mass SQL Injection Worm Propagation Using The Markov Chain (마코브 체인을 이용한 Mass SQL Injection 웜 확산 예측에 관한 연구)

  • Park, Won-Hyung;Kim, Young-Jin;Lee, Dong-Hwi;Kim, Kui-Nam J.
    • Convergence Security Journal
    • /
    • v.8 no.4
    • /
    • pp.173-181
    • /
    • 2008
  • Recently, Worm epidemic models have been developed in response to the cyber threats posed by worms in order to analyze their propagation and predict their spread. Some of the most important ones involve mathematical model techniques such as Epidemic(SI), KM (Kermack-MeKendrick), Two-Factor and AAWP(Analytical Active Worm Propagation). However, most models have several inherent limitations. For instance, they target worms that employ random scanning in the network such as CodeRed worm and it was able to be applied to the specified threats. Therefore, we propose the probabilistic of worm propagation based on the Markov Chain, which can be applied to cyber threats such as Mass SQL Injection worm. Using the proposed method in this paper, we can predict the occurrence probability and occurrence frequency for each threats in the entire system.

  • PDF

A Survey on the Dietary Life toy Kimchi of Housewives in Wonju Area (김치에 관한 원주지역 주부들의 식생활 실태조사)

  • 노정미
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.14 no.4
    • /
    • pp.319-337
    • /
    • 2004
  • The purpose of this study was to investigate the dietary life about Kimchi of the housewives. Self-administrated questionnaires were completed by 322 housewives in Wonju area. The results were as follows: In the point of housewives' domestic duties, over 50% of housewives took care of their domestic duties alone, and the rate who learned how to manage domestic duties from their mothers before marriage decreased as the age got younger. 77.6% of housewives responded that both man and woman could manage a dietary life at home in the future, and the rate of such response was higher as their educational careers were higher and they were younger. In the point of housewives' basic situation about Kimchi, the rate of housewives who knew how to prepare kimchi was high as they were older, and the holding rate of a refrigerator for Kimchi was high as much as 72.4%. In the point of preparation for Kimchi, the rate who made Kimchi by themselves was high, but the rate of preparing Kimchi by their parents for them was higher in the twenties. Frequency of making Kimchi, an amount or a kind of Kimchi were notably different according to housewives' age, a type of their family, the number of their family, and their having a job or not. Housewives' opinion of a market kimchi was that it was expensive, and not sanitary, and rate of purchasing Kimchi was also low. In the point of the prepartion method of Kimchi for the winter, the rate who gained Kimchi from their parents was higher as they lived in an apartment, and had a nuclear family, and had the lesser family members. In an amount of Kimchi prepared for the winter, 11∼22 heads were 23.9% and 21∼30 heads were 21.9%. In the point of the method preparing Kimchi in the future, 53.8% of housewives responded that they would make by themselves, and 28.0% answered they would prepare or purchase. 77.4% of housewives answered that they would teach how to make Kimchi to their children. In conclusion, in housewives of Wonju area, wanted to make Kimchi by themselves and wanted their children to learn how to make Kimchi.

  • PDF

A Study on Community Senior Citizen Center as the Senior Health Care Center Vitalization Plan Measures

  • Jung, Yun-kyung
    • Journal of Korean Clinical Health Science
    • /
    • v.4 no.4
    • /
    • pp.680-688
    • /
    • 2016
  • Purpose. This study aims to explore Situations and Problems of the Community Senior Citizen Center as the senior health care and the Elderly's Leisure status. Then, aims to arrange Activation Vitalization Plan of the senior's leisure in Community Senior Citizen Center. Methods. The literature and data used in this study was based on a questionnaire survey, mostly from Gyeongki-Do Community Senior Citizen Center Branch and statistical research data. Literature review and analysis frequency was by reference to the paperback and academic papers related to the senior health welfare. Results. First, the period of the seniors with the Community Senior Citizen Center as health facilities has appeared in 6-10years(32.8%), followed by the response showing that more than 10years(32.4%). Therefore, it reveals that the senior live in the same region in the long term. Second, the number of days that the senior health care the Community Senior Citizen Center has been used by the senior was over 5days. This result was supported by 608people(61.7%). Both men and women replied that they use the health center more than five days. Third, the number of the senior who responded that they use the Community Senior Citizen Center as health facilities 629people(63.9%). They replied that they use the facilities mostly afternoon. The senior use the facilities all day appeared to 263people(26.7%). Conclusions. It seems like that there needs to be a variety of personalized programs that can be added to increase the life satisfaction of the senior participation in leisure programs for the Community Senior Citizen Center as senior health facilities in the future. Additionally, the government needs to require a wide range of financial support for the Community Senior Citizen Center as senior health care and devise the strategies that will lead the health center for the senior need to be actively utilized.