• Title/Summary/Keyword: Response bias

Search Result 317, Processing Time 0.025 seconds

Effects of Nature-Based Programs for Workers in Korea: A Systematic Review

  • Shin, Jong-Yeon;Shin, Won-Sop
    • Journal of People, Plants, and Environment
    • /
    • v.23 no.2
    • /
    • pp.125-138
    • /
    • 2020
  • The aim of this study was to review previous literature to determine the effects of nature-based program for workers. This systematic review was conducted in accordance with National Evidence-based Healthcare Collaborating Agency's guidance for undertaking systematic reviews for intervention. Literature search was performed using National Assembly Digital Library, Korean Studies Information Service System, and Korea Education & Research Information Service for literature published until March 2019. The participants were full-time workers, and intervention of nature-based programs was conducted in the outdoor, indoor, and indirect nature contact exposures, with comparators in the control group who did not receive the treatment. The results showed that the programs were effective in physical, psychological, and social health. The methodological quality of randomized controlled trials (RCT) was assessed using the Cochrane Risk of Bias(RoB) tool, while non-randomized controlled trials (N-RCT) were assessed using the Cochrane Risk of bias assessment tool for non-randomized studuies (RoBANS). A total of 16 studies were selected for assessment: two RCTs, 10 N-RCTs, and four one-group pretest-posttest designs. Most interventions were provided at the workplace and in the community. There were many kinds of nature-based interventions, and forest therapy and horticultural therapy programs were most common. Various interventions for workers effectively improved job stress, depression, serum cortisol and stress-response. However, the included studies lacked methodological rigor. Future research is needed to evaluate the long-term effectiveness of nature-based programs for workers using rigorous research designs.

Attractiveness Valuation of Phenomenal Architectural Aesthetic by Mixing the Fuzzy Logic with Contingent Valuation - Availing the Use Fares of Facility within Nodle Islet Cultural Center as Valuation Scale - (퍼지논리와 가상가치법 혼합을 통한 현상적 건축미의 매력가치 - 노들섬 문화센터 시설이용료를 가치 척도로 -)

  • Lee, Dong-Joo;Ko, Eun-Hyung
    • Journal of the Architectural Institute of Korea Planning & Design
    • /
    • v.34 no.5
    • /
    • pp.3-10
    • /
    • 2018
  • The purpose of this study is to estimate the attractiveness value according to the preference level on architectural aesthetic. This research starts from the concept that aesthetic is phenomenon and from the viewpoint of 'attraction value' which affects goods. Interactive internet surveys were conducted for 500 citizens of Seoul metropolitan city who are potential users of the Nodle Islet Cultural Center. Based on the scenarios and questionnaires with fuzzy models, we have examined the evaluation of architectural aesthetic and monetary willing-to-payment, and estimated the economic value by preference level of architectural aesthetic through linear regression analysis. The main results of the study are as follows: First, the economic value of the Nodle Islet Cultural Center was estimated at ?15,683.43/person. Residents of Seoul metropolitan city were willing to accept the increase in the above-mentioned amount of the facility fares when their preferred works (average 86.81 points) were constructed. (P <0/05) Second, it is confirmed that the economic value increases dramatically as the preference level of architectural aesthetic increases. Third, it is presumed that the infinite valuation of architectural aesthetic and the problem of free riding coexist in the estimation of economic valuation of architectural aesthetic for public buildings. Fourth, by mixing the fuzzy logic with contingent valuation method, starting point bias and no response biases that happened in contingent valuation could be disappeared. bias elimination must be considered seriously because another bias could be happened in full process of the research. The results of this study will serve as a basis for spreading architectural aesthetic value-oriented research from the vague and obscure aesthetic-centered discussion on the existing architectural aesthetic. In addition, it will be an opportunity to draw institutional application and utilization strategy of architectural aesthetic through architectural aesthetic value research.

An Analysis of Particle-clumping Phenomena of a Charged Particle-type Reflective Electronic Display

  • Kim, Young-Cho
    • Transactions on Electrical and Electronic Materials
    • /
    • v.13 no.4
    • /
    • pp.212-214
    • /
    • 2012
  • Both the electrically positive and negative particles in a cell of quick response-liquid powder display (QR-LPD) are surrounded by conductive electrodes on the upper and lower substrate and the dielectric materials of the barrier ribs. Particles in a cell are attached to or detached from the other materials by image force, electric field, Coulomb's force, and Van der Waals' force. Through these forces, the moving particles form an image but induce clumping phenomena. Particles having a large kinetic energy by a large q/m value crash into the opposite electrode with high speed at a large driving voltage and quickly lose electrically charged material. As a result, these particles are clumped and degrade panel performance. The clumped particles in a cell are observed by microscopic photographs and ascertained by a response time. When the bias voltage is increased to 0.68-0.76 $V/{\mu}m$, particle clumping occurs abruptly and the response time increases sharply. This particle clumping is similarly observed after the number of driving times at the driving voltage (0.42-0.64 $V/{\mu}m$).

A Critical Review of the Use of Inferential Statistics in Library and Information Science Research in Korea (추론통계를 사용한 문헌정보학 연구에서 데이터 수집과 분석에 관한 비평적 고찰)

  • Ro Jung-Soon
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.40 no.2
    • /
    • pp.217-242
    • /
    • 2006
  • This Study reviewed 86 research articles using inferential statistics published in 2001-2004 in 4 korean core journals in the field of library and information science. Sampling methods, response rates and nonresponse bias, reliability test, and inferential statistic techniques used in the articles were critically reviewed and analyzed. Nonprobability sampling was mostly used. Average response rate was 74.47%. Parametric statistics were mostly used. Some misunderstandings in using each inferential statistics, especially Reliability Test, Multiple Regression, Factor Analysis, MDS, etc. were reported in this study.

품질관리표본(Quality Control Sample)의 리인터뷰에 의한 사업체조사의 응답오차 측정

  • Kim, Seol-Hui;Park, Hyeon-Yeong
    • Proceedings of the Korean Statistical Society Conference
    • /
    • 2003.10a
    • /
    • pp.53-58
    • /
    • 2003
  • 최근 경제 사회의 급속한 발전에 따라 개인의 활동분야가 다양해지고 개인비밀보호 인식이 커지면서 응답자들이 통계조사에 잘 협조하지 않는 경우가 늘어나고 있다. 따라서 대부분의 통계를 현장조사에 의존하여 생산하고 있는 통계청에서는 현장조사 결과물의 품질상태에 좀 더 관심을 가져야만 하게 되었다. 이러한 현장조사에 대한 풀질관리의 일환으로 현재 통계청에서는 통계별 조사대상으로부터 품질관리표본(Quality Control Sample)을 추출하고 이를 대상으로 리인터뷰를 실시함으로써 응답오차측정, 조사현장의 실터파악, 응답자 의견수렴 등에 활용하고 있다. 리인터뷰는 조사직원의 고의적인 자료조작 또는 보충교육 필요성 등 현장조사업무를 평가하거나 응답분산(simple response variation), 응답편의(response bias) 등을 산출하고, 이를 분석하는 모델을 이용하여 응답결과의 신뢰도를 분석하는데 목적을 두고 있다. 본 연구에서는 품질관리표본(QC Sample) 설계 및 추출, 리인터뷰 시나리오개발, CATI(Computer Assisted Telephone Interviewing)를 이용한 리인터뷰 기법 등을 통계청 사업체조사 모니터링 사례를 중심으로 설명하고 조사직원 특성별 응답오차 측정 및 비교, 정확성 항목에 대한 차이분석 등 격과에 대하여 논하고자 한다.

  • PDF

Preliminary strong ground motion simulation at seismic stations within nuclear power plant sites in South Korea by a scenario earthquake on the causative fault of 2016 Gyeongju earthquake

  • Choi, Hoseon
    • Nuclear Engineering and Technology
    • /
    • v.54 no.7
    • /
    • pp.2529-2539
    • /
    • 2022
  • Stochastic and an empirical Green's function (EGF) methods are preliminarily applied to simulate strong ground motions (SGMs) at seismic stations within nuclear power plant (NPP) sites in South Korea by an assumed large earthquake with MW6.5 (scenario earthquake) on the causative fault of the 2016 Gyeongju earthquake with MW5.5 (mainshock). In the stochastic method, a ratio of spectral amplitudes of observed and simulated waveforms for the mainshock is assumed to be an adjustment factor. In the EGF method, SGMs by the mainshock are simulated assuming SGMs by the 2016 Gyeongju earthquake with MW5.0 (foreshock) as the EGF. To simulate SGMs by the scenario earthquake, a ratio of fault length to width is assumed to be 2:1 in the stochastic method, and SGMs by the mainshock are assumed to be EGF in the EGF method. The results are similar based on a bias of the simulated response spectra by the two methods, and the simulated response spectra by the two methods exceeded commonly standard design response spectra anchored at 0.3 g of NPP sites slightly at a frequency band above 4 Hz, but considerable attention to interpretation is required since it is an indirect comparison.

Occupational Exposure to Knee Loading and the Risk of Osteoarthritis of the Knee: A Systematic Review and a Dose-Response Meta-Analysis

  • Verbeek, Jos;Mischke, Christina;Robinson, Rachel;Ijaz, Sharea;Kuijer, Paul;Kievit, Arthur;Ojajarvi, Anneli;Neuvonen, Kaisa
    • Safety and Health at Work
    • /
    • v.8 no.2
    • /
    • pp.130-142
    • /
    • 2017
  • Background: Osteoarthritis of the knee is considered to be related to knee straining activities at work. The objective of this review is to assess the exposure dose-response relation between kneeling or squatting, lifting, and climbing stairs at work, and knee osteoarthritis. Methods: We included cohort and case-control studies. For each study that reported enough data, we calculated the odds ratio (OR) per 5,000 hours of cumulative kneeling and per 100,000 kg of cumulative lifting. We pooled these incremental ORs in a random effects meta-analysis. Results: We included 15 studies (2 cohort and 13 case-control studies) of which nine assessed risks in more than two exposure categories. We considered all but one study at high risk of bias. The incremental OR per 5,000 hours of kneeling was 1.26 (95% confidence interval 1.17-1.35, 5 studies, moderate quality evidence) for a log-linear exposure dose-response model. For lifting, there was no exposure dose-response per 100,000 kg of lifetime lifting (OR 1.00, 95% confidence interval 1.00-1.01). For climbing, an exposure dose-response could not be calculated. Conclusion: There is moderate quality evidence that longer cumulative exposure to kneeling or squatting at work leads to a higher risk of osteoarthritis of the knee. For other exposure, there was no exposure dose-response or there were insufficient data to establish this. More reliable exposure measurements would increase the quality of the evidence.

Extraversion and Recognition for Emotional Words: Effects of Valence, Frequency, and Task-difficulty (외향성과 정서단어의 재인 기억: 정서가, 빈도, 과제 난이도 효과)

  • Kang, Eunjoo
    • Korean Journal of Cognitive Science
    • /
    • v.25 no.4
    • /
    • pp.385-416
    • /
    • 2014
  • In this study, memory for emotional words was compared between extraverts and introverts, employing signal detection analysis to distinguish differences in discriminative memory and response bias. Subjects were presented with a study list of emotional words in an encoding session, followed by a recognition session. Effects of task difficulty were examined by varying the nature of the encoding task and the intervals between study and test. For an easy task, with a retention interval of 5 minutes (Study I), introverts exhibited better memory (i.e., higher d') than extraverts, particularly for low-frequency words, and response biases did not differ between these two groups. For a difficult task, with a one-month retention period (Study II), performance was poor overall, and only high-frequency words were remembered; also extraverts adopted a more liberal criterion for 'old' responses (i.e., more hits and more false alarms) for positive emotional-valence words. These results suggest that as task difficulty drives down performance, effects of internal control processes become more apparent, revealing differences in response biases for positive words between extraverts and introverts. These results show that extraversion can distort memory performance for words, depending on their emotional valence.

Transferring Calibrations Between on Farm Whole Grain NIR Analysers

  • Clancy, Phillip J.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
    • /
    • 2001.06a
    • /
    • pp.1210-1210
    • /
    • 2001
  • On farm analysis of protein, moisture and oil in cereals and oil seeds is quickly being adopted by Australian farmers. The benefits of being able to measure protein and oil in grains and oil seeds are several : $\square$ Optimize crop payments $\square$ Monitor effects of fertilization $\square$ Blend on farm to meet market requirements $\square$ Off farm marketing - sell crop with load by load analysis However farmers are not NIR spectroscopists and the process of calibrating instruments has to the duty of the supplier. With the potential number of On Farm analyser being in the thousands, then the task of calibrating each instrument would be impossible, let alone the problems encountered with updating calibrations from season to season. As such, NIR technology Australia has developed a mechanism for \ulcorner\ulcorner\ulcorner their range of Cropscan 2000G NIR analysers so that a single calibration can be transferred from the master instrument to every slave instrument. Whole grain analysis has been developed over the last 10 years using Near Infrared Transmission through a sample of grain with a pathlength varying from 5-30mm. A continuous spectrum from 800-1100nm is the optimal wavelength coverage fro these applications and a grating based spectrophotometer has proven to provide the best means of producing this spectrum. The most important aspect of standardizing NIB instruments is to duplicate the spectral information. The task is to align spectrum from the slave instruments to the master instrument in terms of wavelength positioning and then to adjust the spectral response at each wavelength in order that the slave instruments mimic the master instrument. The Cropscan 2000G and 2000B Whole Grain Analyser use flat field spectrographs to produce a spectrum from 720-1100nm and a silicon photodiode array detector to collect the spectrum at approximately 10nm intervals. The concave holographic gratings used in the flat field spectrographs are produced by a process of photo lithography. As such each grating is an exact replica of the original. To align wavelengths in these instruments, NIR wheat sample scanned on the master and the slave instruments provides three check points in the spectrum to make a more exact alignment. Once the wavelengths are matched then many samples of wheat, approximately 10, exhibiting absorbances from 2 to 4.5 Abu, are scanned on the master and then on each slave. Using a simple linear regression technique, a slope and bias adjustment is made for each pixel of the detector. This process corrects the spectral response at each wavelength so that the slave instruments produce the same spectra as the master instrument. It is important to use as broad a range of absorbances in the samples so that a good slope and bias estimate can be calculated. These Slope and Bias (S'||'&'||'B) factors are then downloaded into the slave instruments. Calibrations developed on the master instrument can then be downloaded onto the slave instruments and perform similarly to the master instrument. The data shown in this paper illustrates the process of calculating these S'||'&'||'B factors and the transfer of calibrations for wheat, barley and sorghum between several instruments.

  • PDF

Prognostic factors in Osteosarcoma (골육종의 예후인자)

  • Jeon, Dae-Geun;Lee, Jong-Seok;Kim, Sug-Jun;Yang, Hyun-Seok;Lee, Soo-Yong
    • The Journal of the Korean bone and joint tumor society
    • /
    • v.3 no.1
    • /
    • pp.1-8
    • /
    • 1997
  • Osteosarcoma is the most common primary bony malignancy and its survivorship has been progressed markedly through refined chemotherapy and surgery. But still there are many non-responders and analysis of prognostic factors may be helpful for them. Two hundred and sixty-six patients were enlisted between Mar, 1985 and Sep. 1994. Among them our inclusion criteria were: 1)primary, nonmetastatic classical osteosarcoma 2)extremity in location 3)no prior treatment at other institute and completed neoadjuvant chemotherapy and surgery according to our protocol. One hundred and eleven cases were eligible. Analyzed factors were:age, sex, location, tumor size, and pathologic response. Statistical methods were log-rank test for univariate and Cox's test for multivariate analysis. Male to female ratio was 69:42 with an average age of 17.2 years. Locations of tumor were distal femur 59, proximal tibia 29, and proximal humerus 8. Tumor size were measured by its maximal diameter and 48 cases were above 10cm and 47 cases were below 10cm. For pathologic response, 57 cases showed more than 90% and 54 cases were less than that. Limb salvage procedure was 101 cases and amputation was 10 cases and their local recurrence rate were 3.6%. Average follow-up period was 24(9-78.2) months and their final status was CDF 86, AWD 8, NED 5, and DOD 12 cases. In univariate study: type of operation(p=0.005), tumor size(p=0.005), and pathologic response(p=0.02) were significant variables. Pathologic response(p=0.03) and type of operation(p=0.01) were meaningful prognostic factors on multivariate analysis. But the latter result was interpreted as a bias, so pathologic response remained as a sole meaningful prognostic factor. More aggressive chemotherapy will be needed to improve the survival.

  • PDF