• Journal of Radiation Protection and Research
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• v.36 no.4
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• pp.183-189
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• 2011

To quantitatively evaluate how setup errors in conjunction with dose gradients contribute to the error in IMRT dose quality assurance (DQA) measurements. The control group consisted of 5 DQA plans of which all individual field dose differences were less than ${\pm}5%$. On the contrary, the examination group was composed of 16 DQA plans where any individual field dose difference was larger than ${\pm}10%$ even though their total dose differences were less than ${\pm}5%$. The difference in 3D dose gradients between the two groups was estimated in a cube of $6{\times}6{\times}6\;mm^3$ centered at the verification point. Under the assumption that setup errors existed during the DQA measurements of the examination group, a three dimensional offset point inside the cube was sought out, where the individual field dose difference was minimized. The average dose gradients of the control group along the x, y, and z axes were 0.21, 0.20, and 0.15 $cGy{\cdot}mm^{-1}$, respectively, while those of the examination group were 0.64, 0.48, and 0.28 $cGy{\cdot}mm^{-1}$, respectively. All 16 plans of the examination group had their own 3D offset points in the cube. The individual field dose differences recalculated at the offset points were mostly diminished and thus the average values of total and individual field dose differences were reduced from 3.1% to 2.2% and 15.4% to 2.2%, respectively. The offset distribution turned out to be random in the 3D coordinate. This study provided the quantitative data that support the large individual field dose difference mainly stems from possible geometric errors (e.g., random setup errors) under the influence of steep dose gradients of IMRT field.

• Journal of Ecology and Environment
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• v.41 no.12
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• pp.345-350
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• 2017

Background: Ecological research often requires monitoring of a specific individual over an extended period of time. To enable non-invasive re-identification, consistent external marking is required. Treefrogs possess lateral lines for crypticity. While these patterns decrease predator detection, they also are individual specific patterns. In this study, we tested the use of lateral lines in captive and wild populations of Dryophytes japonicus as natural markers for individual identification. For the purpose of the study, the results of visual and software assisted identifications were compared. Results: In normalized laboratory conditions, a visual individual identification method resulted in a 0.00 rate of false-negative identification (RFNI) and a 0.0068 rate of false-positive identification (RFPI), whereas Wild-ID resulted in RFNI = 0.25 and RFNI = 0.00. In the wild, female and male data sets were tested. For both data sets, visual identification resulted in RFNI and RFPI of 0.00, whereas the RFNI was 1.0 and RFPI was 0.00 with Wild-ID. Wild-ID did not perform as well as visual identification methods and had low scores for matching photographs. The matching scores were significantly correlated with the continuity of the type of camera used in the field. Conclusions: We provide clear methodological guidelines for photographic identification of D. japonicus using their lateral lines. We also recommend the use of Wild-ID as a supplemental tool rather the principal identification method when analyzing large datasets.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.6
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• pp.663-673
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• 2021

Normally, allowable mean overtopping discharge is used as a design parameter for coastal structures. The crest elevation of a structure must ensure wave overtopping discharge within acceptable limits for structural safety and the safety of pedestrians, vehicles, operations, and so on. Some researchers have alternatively proposed using the maximum individual wave overtopping volumes as design criteria during a design storm, since these can provide a better design measure than the mean overtopping rate. This study contributes to the knowledge on maximum individual overtopping volumes in Rayleigh-distributed wave conditions. Two-dimensional physical model tests on typical rubble mound structure geometries were performed, and the new measurement method for individual overtopping was adopted. An empirical formula was proposed to predict the maximum individual overtopping volumes based on the mean overtopping rate, and the reduction effects by the armor crest width on the mean wave overtopping discharge were assessed.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.5
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• pp.967-976
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• 2018

The purpose of this study is to examine the effects of individual and environmental factors on the career identity of Chinese-Korean adolescents in Yanbian, China. Academic achievement and self-esteem were considered as individual factors, and parent attachment and teacher attachment were considered as environmental factors. This study sought to answer the question "Which individual and environmental factors had an effect on the career identity of Chinese-Korean adolescents in Yanbian, China?" The data was collected from 290 middle school students in Yanbian, China through the use of a survey. The results were as follows: self-esteem as an individual factor and teacher attachment as an environmental factor were found to have a significant effect on career identity. Also, teacher attachment as an environmental factor had the greatest effect on career identity. In the conclusion, we considered theoretical and practical implications of this study to improve the career identity of Chinese-Korean adolescents in China.

• 한국경영정보학회:학술대회논문집
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• 2007.06a
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• pp.80-86
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• 2007

In this paper, we identified factors that affect the usage of UCC, which is becoming increasingly popular in our society and throughout the globe. Four hypotheses were tested using a new integrative model of UCC usage, which is built up by incorporating the TAM and the PAD(pleasure-arousal-dominace)model. We analyzed the data collected in our survey of 258 individual UCC users during the period from Oct 2006 to Dec 2006. We found that pleasure and arousal showed a strong significant effect on individual's UCC usage, supporting the findings of the exiting research on TAM. To be specific, arousal had an effect on the UCC usage through its effect on pleasure and self efficacy. Pleasure affected the UCC usage in two ways: First, pleasure affected UCC usage through increasing the ease of UCC service. At the same time, pleasure had a direct effect on the UCC usage. Contrary to what the prior research on technology acceptance suggested, we found ease of use and social influence had no significant effect on individual's UCC usage. We further found that such effects of the ease of use and pleasure factors are more positive in the entertainment-based UCC than in the relationship-based UCC.

• Mass Spectrometry Letters
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• v.7 no.2
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• pp.41-44
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• 2016

Secondary ion mass spectrometry (SIMS) is a promising tool to measure isotope ratios of individual uranium particles in environmental samples for nuclear safeguards. However, the analysis requires prior identification of a small number of uranium particles that coexist with a large number of other particles without uranium. In the present study, this identification was performed by scanning electron microscopy - energy dispersive X-ray analysis with automated particle search mode. The analytical results for an environmental sample taken at a nuclear facility indicated that the observation of backscattered electron images with × 1000 magnification was appropriate to efficiently identify uranium particles. Lower magnification (less than × 500) made it difficult to detect smaller particles of approximately 1 μm diameter. After identification, each particle was manipulated and transferred for subsequent isotope ratio analysis by SIMS. Consequently, the isotope ratios of individual uranium particles were successfully determined without any molecular ion interference. It was demonstrated that the proposed technique provides a powerful tool to measure individual particles not only for nuclear safeguards but also for environmental sciences.

• Journal of Information Technology Services
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• v.11 no.2
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• pp.147-167
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• 2012

In this paper, we attempted to theorize the multi-faceted impacts of smart work on economic activities. In this vein, we adopted socio-economic perspective which includes individual, firm, and social support aspects, and explored the variables related to the quality of life among them. First, smart work patterns are categorized as telework, mobile office, teleconferencing, and social collaboration. And relevant variables are extracted with reference to industrial cases and relevant literatures which investigated economic impacts of digital convergence. Next, with the data collected from experts, following delphi method, validation of variables and explorations of significant factors affecting quality of life were conducted by adopting stepwise regression method. The distinguishing traits of this research are two-folds. The one is the investigation of social support and quality of life aspects of smart work, which has been relatively limited in the digital convergence research field. The other is the comparative analysis of smart work advantages by distinguishing individual and firm aspects separately. The result offers useful insights for socio-economic perspective researches on digital convergence application area.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.4
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• pp.338-343
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• 2011

To obtain the effective sampling estuarine fauna by a passive net in the West Sea of Korea occurring strong tide, catch were collected by bag nets with various sampling trials off Ganghwa Island in November 2009. We compared the difference of community structures (on spring tide vs. neap tide, total sample vs. subsample and 4 nets vs. 1 net) with each species composition as a sampling unit by the Pearson chi-square test. Number of individual at the spring tide was more abundant than that at the neap tide (p<0.0001) although number of species at the spring tide was not significantly different with that at the neap tide (p=0.174). Both number of species (p=0.138) and number of individual (p=0.096) were not significantly different between total sample and random subsample. Number of species was not significantly different between the subsample by 1 net and the subsample by 4 nets (p=0.515), but number of individual was a little different on both samples (p=0.024). In conclusion, we suggest the subsample by 1 net at spring tide as the effective sampling estuarine fauna by a passive net in the West Sea occurring strong tide.

• Journal of the Korean Operations Research and Management Science Society
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• v.22 no.3
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• pp.163-173
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• 1997

Although numerous studies demonstrate that one technique outperforms the others for a given data set, it is hard to tell a priori which of these techniques will be the most effective to solve a specific problem. It has been suggested that the better approach to classification problem might be to integrate several different forecasting techniques by combining their results. The issues of interest are how to integrate different modeling techniques to increase the predictive performance. This paper proposes the post-model integration method, which tries to find the best combination of the results provided by individual techniques. To get the optimal or near optimal combination of different prediction techniques, Genetic Algorithms (GAs) are applied, which are particularly suitable for multi-parameter optimization problems with an object function subject to numerous hard and soft constraints. This study applies three individual classification techniques (Discriminant analysis, Logit model and Neural Networks) as base models for the corporate failure prediction. The results of composite predictions are compared with the individual models. Preliminary results suggests that the use of integrated methods improve the performance of business classification.

• Journal of the Korean Operations Research and Management Science Society
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• v.41 no.4
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• pp.75-93
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• 2016

This study aims at analyzing the relationship between team characteristic and innovation performance. The mediating effect of creative climate on the team characteristic and innovation performance is also measured. Based upon literature review, individual creative characteristics, team diversity, team cohesion, task characteristics are presented as antecedents of team characteristic. Creative climate affects the creative behavior and innovative performance. Creative climate is measured as the Team Climate Inventory (TCI) proposed by Anderson & West (1998) including goal, participative-autonomy and innovative-support. Data were collected from 186 survey responses (54 Teams) out of total 462 (69 teams) from the R&D department of a major ICT firm in Korea. Empirical results show the diversity, cohesion, job characteristic, individual creative characteristic have a positive effect on the creative climate and innovation performance. The participative-autonomy climate factor appears to mediate the relationship between team characteristic (diversity, cohesion, job and individual characteristics) and innovation performance. However, the mediating effects of goals and innovative-support factors were not significant statistically. It was confirmed that the organization can contribute to improve the team innovation performance by facilitating a autonomy and participative climate as well as fostering the team characteristic.