• Title/Summary/Keyword: 표본추출방법

Search Result 609, Processing Time 0.023 seconds

Timing Recovery Algorithm with Slop Compensated for Multi-level PAM Signals (Multi-level PAM신호에 적용 가능한 기울기 보상 심볼타이밍 알고리즘)

  • 전광호;임명섭
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.26 no.11A
    • /
    • pp.1864-1871
    • /
    • 2001
  • In this paper, new symbol timing recovery algorithm is proposed, which is suitable for the digital communication system with Multi-level PAM signals. In the newly proposed symbol timing recovery algorithm, the timing error function is derived by compensating the several difference values between sampled symbol and neighboring symbol every symbol period with mid samples and decided symbol values. Conventional symbol timing recovery methods did not work well in Multi-level PAM signals, but the newly proposed method can be applied to Multi-level PAM signals as well as QPSK. For the performance analysis, the derived variance of the timing error function and the timing error characteristics of S-curve show that the proposed method has better performance than Gardner method and the modified Gardner method.

  • PDF

e-커머스 창업생태계에서의 청년자영업자에 관한 연구 : N사 파트너스퀘어(광주) 이용자를 중심으로

  • Kim, Jong-Seong;Sin, Ji-Man
    • 한국벤처창업학회:학술대회논문집
    • /
    • 2019.11a
    • /
    • pp.21-25
    • /
    • 2019
  • 본 연구의 목적은 N사의 파트너스퀘어(광주) 이용한 경험이 있는 청년자영업자를 대상으로 e-커머스 창업생태계인 온라인쇼핑몰에 진입하는 과정과 성과를 근거이론(Grounded Theory) 방법을 활용해 규명해 보는 데 있다. 본 연구는 심층 면접 조사 자료를 활용했는데, 연구 참여자의 선정에 있어 이론적 표본 추출(Theoretical Sampling)방식을 사용했으며, 스트라우스와 코빈(Strauss & Corbin)이 제시한 개방코딩, 축코딩, 선택코딩 순으로 진행한 후 패러다임모형으로 분석했다. 주요연구결과는 다음과 같다. 첫째, 부모가 e-커머스에 대해 잘 알지 못하거나 부정적이라도 자녀의 창업에 대해서 긍정적이면 자녀가 온라인쇼핑몰을 통한 자영업에 진입하는 것으로 나타났다. 그러나 부모가 e-커머스에 부정적이고, 자녀의 창업에도 부정적이면 자녀는 온라인쇼핑몰을 통한 자영업에 진입하지 못하는 것으로 나타났다. 둘째, 청년층의 e-커머스를 통한 자영업 진입과 성과 창출조건으로 e-커머스 활용능력이 중요한 것으로 나타났는데, 특히 N사의 파트너스퀘어(광주)는 e-커머스 활용능력을 증대시켜, 청년층이 온라인쇼핑몰을 통한 자영업 진입에 긍정적 영향을 주는 것으로 나타났다. 셋째, 청년층은 온라인쇼핑몰을 통한 e-커머스 자영업에 진입한 이후 단순한 매출액 증가 이외에 자존감 상승, 기회발견, 창의성 역량이 강화되는 것으로 나타났다.

  • PDF

Validation of the Measure of Health Literacy for the Elderly (고령자의 건강정보이해능력(Health Literacy) 측정도구 타당화)

  • Chun, Heeran;Cho, Sung-il;Kim, Il-Ho
    • Korean Public Health Research
    • /
    • v.44 no.4
    • /
    • pp.99-109
    • /
    • 2018
  • Objective : Health literacy (HL) is, defined as "the degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions." Being old is one of the main risk factors with limited health literacy. This study aims to adapt Chew's health literacy scale into the Korean language and validate the scale for the use of the elderly. Methods : Data were drawn from the '2016 Seoul Survey on Elderly Health and Functional Assessment, which includes a total of 725 people aged 60 to 79. The sample was randomly divided into two groups for reliability and validity tests of the modified Chew's scale of 8 items. The Korean version of the questionnaire was developed by group translation, expert reviews, and forward-backward translation. Exploratory and confirmatory factor analyses were conducted to assess and validate the factor structure of the scale. Results : Results suggest the two-factor structure ("Understanding" and "Applying" of HL) with 8 items. Exploratory factor analyses of the first sample (n=400) revealed that the internal reliability of the scale was high (Cronbach's ${\alpha}=.904$). Principal axis factoring extracted two factors ("Understanding" and "Applying" of HL) and explained 78.3% of total variance (KMO=.872, Bartlett's ${\chi}^2=2431.3$, df=28, p<.001). Confirmatory factor analysis of the second sample (n=325) was performed and the two-factor model was supported (GFI=.960, CFI=.979, TLI=.969, RMSEA=0.075). Conclusions : This study provides evidence for adequate criterion and validity of the health literacy scale for the community dwelling elderly in Korea.

Communication Types in Nurses Caring for Patients on Hemodialysis (혈액투석실 간호사 의사소통 유형 분석)

  • Kim, Ri Whaol;Nam, Eun Sook
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.22 no.5
    • /
    • pp.42-50
    • /
    • 2021
  • The purpose of this study was to identify and analyze the communication behavior styles of hemodialysis nurses based on the structured Q-methodology. The Q-population was formulated based on literature reviews and in-depth interviews with 10 hemodialysis nurses who were working in hospitals in Seoul and Anyang-si, Gyeonggi Province. A total of 50 Q-samples, which were believed to best represent the communication behavior styles of hemodialysis nurses, were selected from the Q-population by the author and a professor majoring in nursing. 30 P-samples were selected from hemodialysis nurses who were working in primary, secondary, and tertiary hospitals in Seoul. Q-sorting was performed by P-samples and data was analyzed through the pc-QUANL program. The results suggested that there are four types of communication behavior styles of hemodialysis nurses, namely: "type I: listening and speaking courteously with an active mind", "type II: listening and speaking courteously with a receptive mind", "type III: advising with an explanation" and "type IV: super-reasonable with a defensive mind". It is expected that the analytical results described here may provide basic information that can be used to develop educational material for hemodialysis nurses.

Estimating Air Temperature over Mountainous Terrain by Combining Hypertemporal Satellite LST Data and Multivariate Geostatistical Methods (초단주기 지표온도 위성자료와 다변량 공간통계기법을 결합한 산지 지역의 기온 분포 추정)

  • Park, Sun-Yurp
    • Journal of the Korean Geographical Society
    • /
    • v.44 no.2
    • /
    • pp.105-121
    • /
    • 2009
  • The accurate official map of air temperature does not exist for the Hawaiian Islands due to the limited number of weather stations on the rugged volcanic landscape. To alleviate the major problem of temperature mapping, satellite-measured land surface temperature (LST) data were used as an additional source of sample points. The Moderate Resolution Imaging Spectroradiometer (MODIS) system provides hypertemperal LST data, and LST pixel values that were frequently observed (${\ge}$14 days during a 32-day composite period) had a strong, consistent correlation with air temperature. Systematic grid points with a spacing of 5km, 10km, and 20km were generated, and LST-derived air temperature estimates were extracted for each of the grid points and used as input to inverse distance weighted (IDW) and cokriging methods. Combining temperature data and digital elevation model (DEM), cokriging significantly improved interpolation accuracy compared to IDW. Although a cokriging method is useful when a primary variable is cross-correlated with elevation, interpolation accuracy was sensitively influenced by the seasonal variations of weather conditions. Since the spatial variations of local air temperature are more variable in the wet season than in the dry season, prediction errors were larger during the wet season than the dry season.

Estimation of optimal price of freeway traffic information using a price-sensitivity analysis (가격민감도 기법을 이용한 고속도로 교통정보의 적정가치 산정 연구)

  • Lee Eui-Eun;Kim Jun-Jung
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.2 no.1 s.2
    • /
    • pp.85-92
    • /
    • 2003
  • Due to the expansion of freeway networks in Korea, drivers have more routes to choose. Traffic information on various alternative roadway sections and routes may help drivers choose the optimal route that minimizes travel time or cost. Traffic information on roadways is, therefore, invaluable in sense that individual drivers could reduce their travel time or cost by selecting optimal routes, and furthermore total travel cost of the system could be lowered. However, consensus about the price of traffic information that drivers are willing to pay is not made yet. Current price of traffic information is decided according to the price of similar information such as stock, weather and so on. To investigate the value of traffic information, a survey was conducted at freeway rest areas near Seoul Megalopolis area including Kyunggi Province. Eight hundred drivers who had travelled on freeway within a year were randomly selected. Purposive Quota Sampling was used. A price-response function, a relationship between price and sales, was obtained based on the survey, followed by sensitivity analysis

  • PDF

Positioning of Recreation Forests Using Multidimensional Scaling (다차원척도법(多次元尺度法)을 이용(利用)한 자연휴양림(自然休養林) 포지셔닝)

  • Kang, Mi-Hee;Kim, Seong-Il;Hong, Sung-Kwon;Lee, Tae-Hee
    • Journal of Korean Society of Forest Science
    • /
    • v.88 no.2
    • /
    • pp.133-141
    • /
    • 1999
  • The purposes of this study were to evaluate the present management policy of recreation forest under competitive environment with similar types of recreation areas like national parks and to suggest the effective management strategies, using a multidimensional scaling technique. Data were collected from 1200 residents of Seoul, Pusan, Taegu, Kwangju, and Taejon sampled by two stage cluster sampling method. There were some different perceptions between Seoul residents and the others, but most of the respondents perceived recreation forests as uncrowded natural areas with reasonable use fees. The results suggested the need for developing effective marketing strategies to have distinguishing images from national parks that have competitive.

  • PDF

The Effect of Security Majoring Student' Loyalty on Department to Future Direction and Job Choice (경호전공 대학생들의 학과충성도가 진로정체감 및 직업선택과의 관계)

  • Kim, Sungchul;Kim, Jinhwan
    • Journal of the Society of Disaster Information
    • /
    • v.10 no.3
    • /
    • pp.408-418
    • /
    • 2014
  • This study is to clarify the effect of security majoring students' loyalty on department to future direction and job choice to suggest basic data for supporting student to prepare more active school life and future. The research object is security majoring male/female students among Y university in Gyeonggi-do Y city, K university in Gyeongsangbuk-do G city, k university in Gyeonggi-do S city between 1 Fab 2012 to 20 Aug 2012 and we randomly extracted the sample. In this research, we performed exploratory factor analysis and used principal components analysis and selected varimax direct rotation method to prove the reasonability of the contents. We then use the Cronbach's ${\alpha}$ value to measure the trust coefficient and during the process, the repeated or questions lack of correlation were deleted with judgment of researcher to improve trusty and reasonability.

Social Worker and Research Utilization in Social Work Practice (사회복지사들의 조사연구활용에 관한 연구)

  • Chung, Soon-Dool
    • Korean Journal of Social Welfare
    • /
    • v.58 no.2
    • /
    • pp.251-271
    • /
    • 2006
  • The purposes of this study were to investigate the research utilization in social work practice and to examine the factors associated with research utilization. The subjects of this study were social workers participating in social work practice in Korea. The sampling methods used in this study was a multistage sampling strategy. Data were collected by sending mails and follow-up mails to the social workers. Data from 569 of social workers were finally analyzed by ordered regression analysis. The results showed that the level of research utilization by social workers in Korea was very low, but their attitude toward research was positive. The variables affecting research utilization were related to the research ability of social workers, but the variables of research related environment except type of organization were not significant. The variables for research ability of social workers are experiences of utilizing journal articles, experiences of re-education for research methodology, gender, attitude about research usefulness. The variables for research related environment are characteristics of agency setting. The implications of social work research are discussed.

  • PDF

The Relationship between Consumption Value of Sports Products, Upward Comparison Propensity, and Post-Purchase Happiness in Adolescence

  • Byung-Kwan, Lee
    • Journal of the Korea Society of Computer and Information
    • /
    • v.28 no.1
    • /
    • pp.143-150
    • /
    • 2023
  • This paper aims to investigate the relationship between consumption value of sports products, upward consumption propensity, and post-purchase happiness among adolescents. The subjects of the study were extracted from adolescents in Chungcheong-do by convenience sampling method, and 257 people were used in the final analysis. Statistical methods were frequency analysis, correlation analysis, and regression analysis. The research results are as follows. First, social value and exploratory value, which are sub-factors of consumption value, were shown to have a significant effect on upward consumption propensity, but functional value and self-value were found to be statistically insignificant. Second, social value, self-value, and functional value, which are sub-factors of consumption value, had a significant effect on post-purchase happiness, but exploratory value was found to be statistically insignificant. Third, the upward comparison propensity was found to have a significant effect on post-purchase happiness.