• Particle and aerosol research
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• v.18 no.4
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• pp.109-127
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• 2022

Recently, low-cost particulate matter (PM) sensors have been widely used in monitoring mass concentration. Maintaining the accuracy of the sensors is important and requires rigorous performance evaluation and calibration. In this study, two commercial low-cost PM sensors(LCS), Plantower PMS3003 and Plantower PMS7003, were evaluated in the laboratory and field with a reference-grade PM monitor (GRIMM 11-D). Laboratory evaluation was conducted with single/mixed particles of PSL (Poly Styrene Latex) in an acrylic chamber at 20℃ and relative humidity of 20%. Field evaluation was conducted inside a building of Yonsei University (Shinchon) from February 12 to March 31, 2022. In both evaluations, LCS measured values became different from reference measured values when the relative humidity was high or the outdoor air PM10/PM2.5 ratio was high. Based on the field evaluation, the LCS measured values were corrected through four different regression analysis models. As a result, the multivariate polynomial regression analysis model showed highest matching with the reference PM monitor (PM2.5 >0.9, PM10 >0.85). In this model, the PM10/PM2.5 ratio and relative humidity were chosen as independent variables.

• Journal of Technology Innovation
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• v.10 no.1
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• pp.201-217
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• 2002

Researchers, institutes, and government involved in research & development (R&D) are faced with the problem of performing R&D project evaluations. As a real-word case of evaluation, we elicited and reproduced the evaluation process of the national nuclear R&D projects, using a specific case study of Korea. In the methodology, the analytic hierarchy process (AHP) is employed to evaluate and rank the selected nuclear R&D projects which have a wide range of evaluation objectives and characteristics. As a result, we obtained relative ranking for research projects and importance of evaluation criteria. The method and implications can be easily understood and applied by practitioners since it follows naturally the standard practice of evaluating and relative comparisons of performance using evaluation procedures. By applying particular R&D project output to the procedures, project evaluators can compare and prioritize evaluation objectives.

• Health Policy and Management
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• v.30 no.2
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• pp.199-210
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• 2020

Background: Based on the importance of ceasing smoking programs to control the regional disparity of smoking behavior in Korea, this study aims to reveal the variation of smoke rate and determinants of it for 229 provinces. An evaluation of the relative efficiency of the cease smoking program under the consideration of regional characteristics was followed. Methods: The main sources of data are the Korean Statistical Information Service and a national survey on the expenditure of public health centers. Multivariate regression is performed to figure the determinants of regional variation of smoking rate. Based on the result of the regression model, clustering analysis was conducted to group 229 regions by their characteristics. Three clusters were generated. Using data envelopment analysis (DEA), relative efficiency scores are calculated. Results from the pooled model which put 229 provinces in one model to score relative efficiency were compared with the cluster-separated model of each cluster. Results: First, the maximum variation of the smoking rate was 16.9%p. Second, sex ration, the proportion of the elder, and high risk drinking alcohol behavior have a significant role in the regional variation of smoking. Third, the population and proportion of the elder are the main variables for clustering. Fourth, dissimilarity on the results of relative efficiency was found between the pooled model and cluster-separated model, especially for cluster 2. Conclusion: This study figured regional variation of smoking rate and its determinants on the regional level. Unconformity of the DEA results between different models implies the issues on regional features when the regional evaluation performed especially on the programs of public health centers.

• Computers and Concrete
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• v.19 no.1
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• pp.111-120
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• 2017

This study aimed to design the accelerated life testing (ALT) of concrete, which stimulating the special natural environment maximumly. Its evaluation indexes, such as dynamic elastic modulus, mass and ultrasonic velocity were measured, and the variation of relative mass and relative dynamic elastic modulus of concrete were studied. Meanwhile, the microanalysis method was used. Moreover, an exploratory application of the stochastic approach, the Weibull distribution and the lognormal distribution, were made to assess the durability of concrete structures. The results show that the ALT for simulating natural environment is more close to the service process of concrete structure under actual conditions; The relative dynamic elastic modulus can be used as the dominant durability evaluation parameters, because it is more sensitive to the environmental factors compared with the relative quality evaluation parameters; In the course of the concrete deterioration, the destruction of the salt freezing cycle is the dominant factor, supplemented by other factors; Both of those two stochastic approaches can be used to evaluate the reliability of concrete specimens under the condition of ALT; By comparison, The lognormal distribution method is better to describe the reliability process.

• Journal of the Society of Disaster Information
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• v.19 no.2
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• pp.363-371
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• 2023

Purpose: This paper aims to develop evaluation criteria of Plan- 'Understanding the Organization' in the PDCA(Plan-Do-Check-Act) requirements of ISO 22301 which is a global standard in the area of BCMS(Business Continuity Management System). Method: The group of 20 experts in the BCMS checked for the validity of the evaluation criteria of Plan- 'Understanding the Organization' by the modified Delphi technique and relative importance are surveyed by the group. Results: As a result, the 12 evaluation criteria with relative importance that can be applied for BCMS evaluation of the organizations are developed and proposed. Conclusion: In order to introduce a quantitive evaluation in the BCMS, it was concluded that evaluation criteria need to be chosen and given relative importance, thus the criteria with the importance could be used for effective evaluation

• Science of Emotion and Sensibility
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• v.17 no.4
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• pp.41-50
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• 2014

This study examined the characteristics of brain's reaction pattern concerning the preference for product images and compared them with the result of subjects' intuitive evaluation of their preference for the same materials. Two tests were conducted; the first one that calculated comfort properties based on brainwave measurements in order to examine the impression given by the images of products presented separately, one-by-one, and the second one that had subjects evaluate the preference directly by comparing the images of all products simultaneously. The first test was titled 'Independent Cognitive Response' and the second test, 'Relative Cognitive Response', and their characteristics were as follows. In the 'Independent Cognitive Response', the state of emotion was expressed in absolute values based on the comparison with the information accumulated through the subject's own experience and the feeling expressed as 'pleasant' or 'unpleasant' persisted as absolute values. In the 'Relative Cognitive Response', the state of emotion relative to the information of other images compared in the stage of perceiving the images was expressed, and in this case, the state of emotion described as 'calm' or 'excited' acted as relative values.

• Journal of Auto-vehicle Safety Association
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• v.12 no.3
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• pp.43-51
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• 2020

Currently, the second level of the six stages of self-driving technology, as defined by SAE, is commercialized, and the third level is preparing for commercialization. The purpose of ACC is to be evaluated as a system useful for preventing and preventing accidents by minimizing driver fatigue through longitudinal speed control and relative distance control of the vehicle. In this regard, for the study of safety assessment methods in the practical environment of ACC. Distance measurement method using monocular camera and data acquisition equipment such as DGPS are utilized. Based on the evaluation scenario considering the domestic road environment proposed by the preceding study, the relative distance obtained from equipment such as DPGS and the relative distance using a monocular camera in the actual test is verified by comparing and analyzing the safety assessment. The comparison by scenario results showed a minimum error rate of 3.83% in Scenario 1 and a maximum of 14.61% in Scenario 6. The cause of the maximum error is that the lane recognition is not accurate in the camera image and irregular operation conditions such as rushing in or exiting the surrounding area from the walkway. It is expected that safety evaluation using a monocular camera will be possible for other ADAS systems in the future.

• Korean Management Science Review
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• v.21 no.2
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• pp.191-213
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• 2004

This study addresses the evaluation criteria of multimedia authoring tools(MATs), the way which decision-maker can exclude outlier matrix from group using the concept of the compatibility index, and how AHP can be applied to the selection of MATs in a group decision-making environment. The AHP technique allows an evaluator to quantify the relative importance of elements at each hierarchy and to calculate the composite relative weights for each product(i.e. MATs). This decision process allows setting to priority of the MATs based on the AHP. The results indicated that technical ability of MATs was the most significant factor in affecting their decision, trailed by managerial efficiency and vendor support. To the experts, multimedia data support was the less important than development interface. Also, the results indicated that product A(0.510) was their first choice, trailed by product C(0.286) and B(0.204). Assessing the composite relative weights revealed that expert group's members were consistent with the rankings of decision variables(evaluation criteria variables) statistically in selecting their MATs. Therefore, we believed that expert group's members have achieved sufficient agreement to permit the use of geometric mean to average the group's preference without obscuring the differences of individual opinions.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.9
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• pp.1737-1744
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• 2009

This study calculated the relative importance between evaluation factors of websites focused on culture and tourism in J region by 3C_D_T evaluation model of website. That is, this paper was analyzed by AHP (analytic hierarchy process) and calculated the relative weights and preference. In conclusion, this study showed that content was the most important factor and proposed the improvement planning through sensitivity analysis.

• Journal of the Korean housing association
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• v.20 no.2
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• pp.69-76
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• 2009

The evaluation of the quality of residential environment, in the planning process, is very important. If the environmental quality can be measured on the design scheme itself, it would be possible not only to estimate the residential environment, but also to apply the results of measuring in the planning and design of new residential projects. This study aimed at estimating the relative weights of the constituents of a residential environment by AHP (Analytic Hierarchy Process). For the detailed analysis of relative weights, the respondent of survey were composed of two different groups-dwellers and experts. The findings are as follows (:) 1) the relative weights of residential constituents were different between the respondent groups; 2) the relative weights of residential constituents were different according to socio-demographic characteristics; and 3) for the practical application of estimation results of the relative weights, the relation between residential performance constituents and physical design elements should be considered.