• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.5
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• pp.70-81
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• 2020

Point-by-point data, which is abundantly collected by vehicles with embedded GPS (Global Positioning System), generate useful information. These data facilitate decisions by transportation jurisdictions, and private vendors can monitor and investigate micro-scale driver behavior, traffic flow, and roadway movements. The information is applied to develop app-based route guidance and business models. Of these, speed data play a vital role in developing key parameters and applying agent-based information and services. Nevertheless, link speed values require different levels of physical storage and fidelity, depending on both collecting and reporting intervals. Given these circumstances, this study aimed to establish an appropriate collection interval to efficiently utilize Space Mean Speed information by vehicles with embedded GPS. We conducted a comparison of Probe-vehicle data and Image-based vehicle data to understand PE(Percentage Error). According to the study results, the PE of the Probe-vehicle data showed a 95% confidence level within an 8-second interval, which was chosen as the appropriate collection interval for Probe-vehicle data. It is our hope that the developed guidelines facilitate C-ITS, and autonomous driving service providers will use more reliable Space Mean Speed data to develop better related C-ITS and autonomous driving services.

• Analytical Science and Technology
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• v.33 no.6
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• pp.262-273
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• 2020

A fluorine content analysis method for krill oils, which is a representative oil formulation in foods, was developed in compliance with the Korea Food and Drug Ministry's "Guidelines for Validation of Testing Methods Related to Food". Using this method for krill oils, the presence of impurities was evaluated via combustion-ion chromatography (C-IC). A review of published technical data on fluorine in krill oils showed that while the traditional wet potentiometric method was typically used, it was not reliable. Moreover, there was no food testing/analysis laboratory in Korea to perform a fluorine test analysis on such an oil matrix. Therefore, we identified halogen (fluorine) tests, developed to national and international standards, and developed a test method suitable for krill oils by selecting a C-IC method that is sufficiently applicable to the oil matrix. Based on the characteristics of the oil matrix, the optimal test method was established through various experiments by reviewing the concerns related to loss and interference in the preparation and introduction of samples. The fluorine content test was carried out on 11 krill oil products that were purchased online. Most products (with the exception of only one) were found to contain less than the reporting limit obtained by the test method. Furthermore, after additional testing, a high fluorine content of approximately 2,000 ~ 3,000 mg/kg was detected on the krill surface, although the concentration varied depending on the area of the krill. A comparison with samples from two ISO/IEC 17025 testing laboratories confirmed that there was no significant difference in the statistical analysis results obtained by ANOVA among the three laboratories. A testing guide for fluorine content analysis was completed.

• Journal of Korean Medicine Rehabilitation
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• v.32 no.1
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• pp.89-106
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• 2022

Objectives In this study, a scoping review was conducted to inform decision-making related to traditional Korean medicine for people with disabilities in the future. Methods Seven databases were searched to find previous studies on traditional Korean medicine for people with disabilities. Studies published until August 2021 were considered. Using the methodology of scoping review, research on traditional Korean medicine for people with disabilities was reviewed with the following steps: 1) drawing research questions, 2) searching for related studies, 3) selecting studies, 4) extracting data, and 5) analyzing and reporting results. Results Out of 2,072 studies, 7 research papers and 10 reports were finally selected. The research papers included 5 cases studies, 1 survey study, and 1 chart review. Most studies used herbal medicine and acupuncture treatment, but the reports on the interventions were not detailed. The reports included policy studies, project performance guidelines, and project results reports, and most of the evaluation indicators tended to be standardized. Conclusions This study reviewed the literature on traditional Korean medicine for people with disabilities. It presents future directions for clinical research on traditional Korean medicine for people with disabilities and can be used to inform healthcare policies and clinical practice. In the future, quantitative research such as clinical trials, meta-analysis, and health insurance big data analysis is needed to understand the current status and effects of traditional Korean medicine for people with disabilities. In addition, qualitative research is necessary to identify unmet demands of traditional Korean medicine for people with disabilities.

• Journal of Navigation and Port Research
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• v.46 no.4
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• pp.338-343
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• 2022

As the revitalization of the global maritime industry continues, the number of foreign ships navigating the maritime territories of maritime neighboring countries has rapidly increased. However, large-scale marine accidents have occurred, caused by the insufficient establishment of a system for management and operation relative to vessels' safety-condition. To address that, the IMO has granted the right to exercise port state control, especially for foreign vessels, to countries with jurisdiction over maritime territories with strengthening regulations and guidelines. In particular, the Republic of Korea, as a member of the TOKYO MOU, is conducting PSC, but as of 2020, the proportion of foreign ships was three times higher than that of national ships that called in domestic ports. However, the inspection rate was low at 9% which has not met the recommended level by the TOKYO MOU. Thus, this study conducted an IPA analysis as well as content analysis, by collecting the practical opinions and views of PSCO through objective questionnaires and written expert interviews, for improving the efficiency and effectiveness of domestic PSC. As a result, it was derived that the importance and performance related to human factors such as life on board, working environment, and response to safety accidents should be improved in to raise the quality of PSC inspection. Additionally, the work environment and performance of PSC in domestic ports for foreign vessels could be improved, if multifaceted support bases are established, for administrative unification of related tests for PSC, recruitment of PSCO, activation of the defection-reporting system, reorganization of the PSC execution group, etc.

• The Korean Journal of Nuclear Medicine Technology
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• v.26 no.1
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• pp.15-26
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• 2022

Purpose Recently, in the process of examining the self-disposal of radioactive waste by the Korea Institute of Nuclear Safety, it is difficult to reach the final approval process for self-disposal. In connection with this, we intend to increase the processing efficiency of self-disposal and strengthen safety by analyzing cases of recent supplementary matters. Materials and Methods From 2018 to 2021, we compare and review a supplementary requests that preparing the procedures and plans for the self-disposal of radioactive waste by 20 institutions. In this regard, based on the provisions of the Atomic Energy Safety Act, we derive a detailed proposals for the self-disposal of radioactive waste by arranging the review processing period calculation and supplementary requests that occurred during the review process. Results The representative supplementary requests of the Korea Institute of Nuclear Safety are the calculation of the storage period by type and nuclide of radioactive waste, the contents of the packaging container, the RASIS reporting method, the planned storage method for self-disposal, confirmation of the final disposal company, and the storage period of the waste filter Calculation, radioactive labeling, etc. And it is emphasized as important. Conclusion The expected effects of the guidelines reflecting the latest supplements include reduction of the time required for document preparation and increase of work processing efficiency, improvement of storage efficiency in the radioactive waste storage room, and economic cost reduction. If the radioactive waste self-disposal guideline presented in this study is applied to the field, it is thought that it will be helpful in improving the work efficiency of those who are experiencing difficulties.

• Journal of the Korea Convergence Society
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• v.13 no.5
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• pp.219-228
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• 2022

In order to improve audit quality, it is essential to understand the occurrence of disagreement between auditors and managers, and this study aims to analyze the impact of Business Strategies on audit risk and accounting audit delay. To this end, we conducted an empirical analysis using sample 2,910 firm-year data from 2018 to 2020 of KOSPI-listed and KOSDAQ-listed companies. The results of the empirical analysis of this study are as follows. First, compared to the companies of defender type, prospectors can expand audit procedures for new products, R&D costs, and intangible assets, and increase audit delays due to disagreement between managers and auditors. Second, compared to KOSPI-listed companies, the prospectors in KOSDAQ are more likely to have lower financial reporting quality, which further increases audit delays. The results of this study analyzed whether a company's Business Strategy affects the possibility of disagreement between an auditor and a company, and verified whether there is a difference in the audit report lag by stock market. The results of this study show that auditors' strong duty of care is needed for the companies of prospector type with high audit risk, and it is meaningful to present reinforced audit systems and specific guidelines for the companies of prospector type through the definition of prospector type. It also enables the expansion of research to identify the relationship between non-financial factors and audit risks that make up the companies of prospector type.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.25 no.5
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• pp.353-375
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• 2022

No systematic review to date has examined histopathological parameters in relation to native liver survival in children who undergo the Kasai operation for biliary atresia (BA). A systematic review and meta-analysis is presented, comparing the frequency of native liver survival in peri-operative severe vs. non-severe liver fibrosis cases, in addition to other reported histopathology parameters. Records were sourced from MEDLINE, Embase, and CENTRAL databases. Studies followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and compared native liver survival frequencies in pediatric patients with evidence of severe vs. non-severe liver fibrosis, bile duct proliferation, cholestasis, lobular inflammation, portal inflammation, and giant cell transformation on peri-operative biopsies. The primary outcome was the frequency of native liver survival. A random effects meta-analysis was used. Twenty-eight observational studies were included, 1,171 pediatric patients with BA of whom 631 survived with their native liver. Lower odds of native liver survival in the severe liver fibrosis vs. non-severe liver fibrosis groups were reported (odds ratio [OR], 0.16; 95% confidence interval [CI], 0.08-0.33; I²=46%). No difference in the odds of native liver survival in the severe bile duct destruction vs. non-severe bile duct destruction groups were reported (OR, 0.17; 95% CI, 0.00-63.63; I²=96%). Lower odds of native liver survival were documented in the severe cholestasis vs. non-severe cholestasis (OR, 0.10; 95% CI, 0.01-0.73; I²=80%) and severe lobular inflammation vs. non-severe lobular inflammation groups (OR, 0.02; 95% CI, 0.00-0.62; I²=69%). There was no difference in the odds of native liver survival in the severe portal inflammation vs. non-severe portal inflammation groups (OR, 0.03; 95% CI, 0.00-3.22; I²=86%) or between the severe giant cell transformation vs. non-severe giant cell transformation groups (OR, 0.15; 95% CI, 0.00-175.21; I²=94%). The meta-analysis loosely suggests that the presence of severe liver fibrosis, cholestasis, and lobular inflammation are associated with lower odds of native liver survival in pediatric patients after Kasai.

• Journal of East Asia Management
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• v.4 no.1
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• pp.23-51
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• 2023

We investigate whether the association between management overconfident tone and the level of audit effort measured by audit fees and hours differs depending on the level of earnings management. Prior studies suggest that firms led by overconfident managers are likely to initiate risky investments, report low quality financial statements, and have material weaknesses in internal control system. These characteristics, combined together, result in higher audit risk. At the same time, auditors assess audit risk based on the quality of financial reporting, measured by level of earnings management. As a result, the assess audit risk is likely to reflect the combined effect of management overconfidence and the level of earnings management. In this paper, we investigate whether auditors differentiate the effects of real earnings management (REM) and accrual-based earnings management (AEM) when they assess the audit risk related management overconfident. Using the CEO's letter published in 2018, we measure the CEO's tone representing the degree of overconfidence (i.e., activity). Based on this measure, we find that the positive association between managerial overconfident tone and audit effort is more pronounced as the level of REM is higher. However, we find that the baseline association does not vary depending on the level of AEM. These results suggest that auditors consider the managerial overconfident severer when such characteristic accompany the higher level of REM, which can be outcome of aggressive business decisions possibly leading to the higher audit risks. We further find that these results are stronger for Big 4 auditors and continuing auditors. This paper contributes to the literature and practice as follows. First, we provide contextual evidence on how auditors reflect managerial characteristics in the audit process by documenting that auditors actively increase their audit efforts only when overconfident managerial characteristics are highly likely to lead to audit risk. This result suggests that auditors conduct external auditing considering both the efficiency and effectiveness of the audit process. Second, we suggest that auditors use information obtained from a wide range of sources to identify audit risks. Our results provide evidence of how the auditing standards, which do not provide detailed guidelines for audit risk assessment, are being applied in practice. Finally, our results also enhance the understanding of how audit fees are determined. Combined with the studies related to audit pricing, we provide the important reference for discussion between the auditor and the auditee about the audit fee that has created acute tension after the enforcement of the new External Audit Act.

• Korean Journal of Radiology
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• v.22 no.7
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• pp.1066-1076
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• 2021

Objective: To evaluate the performance of the 2018 Korean Liver Cancer Association-National Cancer Center (KLCA-NCC) Practice Guidelines (hereafter, PG) for the diagnosis of hepatocellular carcinoma (HCC) using gadoxetic acid-enhanced MRI, compared to the Liver Imaging-Reporting and Data System (LI-RADS) version 2018 (hereafter, v2018). Materials and Methods: From January 2013 to October 2015, treatment-naïve hepatic lesions (≥ 1 cm) on gadoxetic acid-enhanced MRI in consecutive patients with chronic hepatitis B or cirrhosis were retrospectively evaluated. For each lesion, three radiologists independently analyzed the imaging features and classified the lesions into categories according to the 2018 KLCA-NCC PG and LI-RADS v2018. The imaging features and categories were determined by consensus. Generalized estimating equation (GEE) models were used to compare the per-lesion diagnostic performance of the 2018 KLCA-NCC PG and LI-RADS v2018 using the consensus data. Results: In total, 422 lesions (234 HCCs, 45 non-HCC malignancies, and 143 benign lesions) from 387 patients (79% male; mean age, 59 years) were included. In all lesions, the definite HCC (2018 KLCA-NCC PG) had a higher sensitivity and lower specificity than LR-5 (LI-RADS v2018) (87.2% [204/234] vs. 80.8% [189/234], p < 0.001; 86.2% [162/188] vs. 91.0% [171/188], p = 0.002). However, in lesions of size ≥ 2 cm, the definite HCC had a higher sensitivity than the LR-5 (86.8% [164/189] vs. 82.0 (155/189), p = 0.002) without a reduction in the specificity (80.0% [48/60] vs. 83.3% [50/60], p = 0.15). In all lesions, the sensitivity and specificity of the definite/probable HCC (2018 KLCA-NCC PG) and LR-5/4 did not differ significantly (89.7% [210/234] vs. 91.5% [214/234], p = 0.204; 83.5% [157/188] vs. 79.3% [149/188], p = 0.071). Conclusion: For the diagnosis of HCC of size ≥ 2 cm, the definite HCC (2018 KLCA-NCC PG) had a higher sensitivity than LR-5, without a reduction in specificity. The definite/probable HCC (2018 KLCA-NCC PG) had a similar sensitivity and specificity to that those of the LR-5/4.

• Asia pacific journal of information systems
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• v.19 no.4
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• pp.47-75
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• 2009

Recently, researches on Management Information Systems (MIS) have laid out theoretical foundation and academic paradigms by introducing diverse theories, themes, and methodologies. Especially, academic paradigms of MIS encourage a user-friendly approach by developing the technologies from the users' perspectives, which reflects the existence of strong causal relationships between information systems and user's behavior. As in other areas in social science the use of structural equation modeling (SEM) has rapidly increased in recent years especially in the MIS area. The SEM technique is important because it provides powerful ways to address key IS research problems. It also has a unique ability to simultaneously examine a series of casual relationships while analyzing multiple independent and dependent variables all at the same time. In spite of providing many benefits to the MIS researchers, there are some potential pitfalls with the analytical technique. The research objective of this study is to provide some guidelines for an appropriate use of SEM based on the assessment of current practice of using SEM in the MIS research. This study focuses on several statistical issues related to the use of SEM in the MIS research. Selected articles are assessed in three parts through the meta analysis. The first part is related to the initial specification of theoretical model of interest. The second is about data screening prior to model estimation and testing. And the last part concerns estimation and testing of theoretical models based on empirical data. This study reviewed the use of SEM in 164 empirical research articles published in four major MIS journals in Korea (APJIS, ISR, JIS and JITAM) from 1991 to 2007. APJIS, ISR, JIS and JITAM accounted for 73, 17, 58, and 16 of the total number of applications, respectively. The number of published applications has been increased over time. LISREL was the most frequently used SEM software among MIS researchers (97 studies (59.15%)), followed by AMOS (45 studies (27.44%)). In the first part, regarding issues related to the initial specification of theoretical model of interest, all of the studies have used cross-sectional data. The studies that use cross-sectional data may be able to better explain their structural model as a set of relationships. Most of SEM studies, meanwhile, have employed. confirmatory-type analysis (146 articles (89%)). For the model specification issue about model formulation, 159 (96.9%) of the studies were the full structural equation model. For only 5 researches, SEM was used for the measurement model with a set of observed variables. The average sample size for all models was 365.41, with some models retaining a sample as small as 50 and as large as 500. The second part of the issue is related to data screening prior to model estimation and testing. Data screening is important for researchers particularly in defining how they deal with missing values. Overall, discussion of data screening was reported in 118 (71.95%) of the studies while there was no study discussing evidence of multivariate normality for the models. On the third part, issues related to the estimation and testing of theoretical models on empirical data, assessing model fit is one of most important issues because it provides adequate statistical power for research models. There were multiple fit indices used in the SEM applications. The test was reported in the most of studies (146 (89%)), whereas normed-test was reported less frequently (65 studies (39.64%)). It is important that normed- of 3 or lower is required for adequate model fit. The most popular model fit indices were GFI (109 (66.46%)), AGFI (84 (51.22%)), NFI (44 (47.56%)), RMR (42 (25.61%)), CFI (59 (35.98%)), RMSEA (62 (37.80)), and NNFI (48 (29.27%)). Regarding the test of construct validity, convergent validity has been examined in 109 studies (66.46%) and discriminant validity in 98 (59.76%). 81 studies (49.39%) have reported the average variance extracted (AVE). However, there was little discussion of direct (47 (28.66%)), indirect, and total effect in the SEM models. Based on these findings, we suggest general guidelines for the use of SEM and propose some recommendations on concerning issues of latent variables models, raw data, sample size, data screening, reporting parameter estimated, model fit statistics, multivariate normality, confirmatory factor analysis, reliabilities and the decomposition of effects.