• Journal of the Korean Society of Radiology
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• v.83 no.2
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• pp.331-343
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• 2022

Purpose To systematically compare the performance of liver imaging reporting and data system treatment response (LR-TR) with the modified Response Evaluation Criteria in Solid Tumors (mRECIST) for diagnosing viable hepatocellular carcinoma (HCC) treated with locoregional therapy (LRT). Materials and Methods Original studies of intra-individual comparisons between the diagnostic performance of LR-TR and mRECIST using dynamic contrast-enhanced CT or MRI were searched in MEDLINE and EMBASE, up to August 25, 2021. The reference standard for tumor viability was surgical pathology. The meta-analytic pooled sensitivity and specificity of the viable category using each criterion were calculated using a bivariate random-effects model and compared using bivariate meta-regression. Results For five eligible studies (430 patients with 631 treated observations), the pooled per-lesion sensitivities and specificities were 58% (95% confidence interval [CI], 45%-70%) and 93% (95% CI, 88%-96%) for the LR-TR viable category and 56% (95% CI, 42%-69%) and 86% (95% CI, 72%-94%) for the mRECIST viable category, respectively. The LR-TR viable category provided significantly higher pooled specificity (p < 0.01) than the mRECIST but comparable pooled sensitivity (p = 0.53). Conclusion The LR-TR algorithm demonstrated better specificity than mRECIST, without a significant difference in sensitivity for the diagnosis of pathologically viable HCC after LRT.

• Journal of Internet Computing and Services
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• v.12 no.4
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• pp.35-43
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• 2011

Cognitive Radio (CR) ad hoc network is highly considered as one of promising future ad hoc networks, which enables opportunistic access to under-utilized licensed spectrum. Similarly to other CR networks, the spectrum sensing is a prerequisite in CR ad hoc network. Collaborative spectrum sensing can help increasing sensing performance. For such an infrastructureless network, however the coordination for the sensing collaboration is really complicated due to the lack of a central controller. In this paper, we propose a novel collaborative spectrum sensing scheme in which the final decision is made by the node with the highest data reliability based on a sequential Dempster Shafer theory. The collaboration of sensing data is also executed by the proposed contention-aware reporting mechanism which utilizes the sensing data reliability order for broadcasting spectrum sensing result. The proposed method reduces the collecting time and the overhead of the control channel due to the efficiency of the ordered sequential combination while keeping the same sensing performance in comparison with the conventional cooperative centralized spectrum sensing scheme.

• Women's Health Nursing
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• v.5 no.1
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• pp.146-165
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• 1999

The purpose of this paper was to identify the performance of health promoting lifestyles and health perception over 18 years old women living Wonju city so that the results will be based for setting up women's health nursing center. The subjects were 1080 women selected by stratified and purposive sampling. The data were collected by self reporting questionnaire and interview from May to June, 1998. Data were analyzed by SPSS win program. The results were as follows : 1. The range of age was 18-84 years, The proportion according to women's lifecycle was premarital group 20.0%, delivery and rearing group 49.9%, over middle aged-elderly group 29.8%. 2. The mean menarchial age was 15.2 and menopausal age was 48. Mean frequenices of pregnancy is 2.4 and artificical abortion rate is 36.4%. Primary cause of abortion was unwanted babies 42.8%. The practice rate of family planning was 79.4% and permanent sterilization rate was 37.6%. 3. Fatigue was predominated problem in target population. Depression and headache was predominated in premarital group, headache and nervous felling in delivery and rearing group, arthritis and loss of memory in over middle aged-elderly group. 4. Only 13.7% of the target population make some efforts for their health in compare to 85.9% have attention for their health. Perception of unhealthy rate was 9.1% in premarital group, 24.8% in delivery and rearing group, 30.1% in middle aged-elderly group. 5. The average score of the HPLP(Health Promoting Lifestyle Profile) was 2.41. The variable with the highest degree of performance was interpersonal relationship, whereas the one with the lowest degree was the professional health maintenance. The significant difference was found in HPLP according to age, residential area, marital status, educational level, income level. 6. Majority(95.1%) of the target population agreed on necessity for women's health nursing center. Proper location area was presented to women's center and public health center. The priority for health education program was proper diet, family health, stress management, and exercise. In conclusion, we should prepare the education program for women's health according to women's lifecycle, because health perception, HPLP, and education program needed was differentiated in women's lifecycle. Also we suggest that women's health nursing center based community was needed for proper management of women's health.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.2A
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• pp.107-114
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• 2008

In wireless access systems, there has been much interest in enhancing the performance of orthogonal frequency division multiplexing OFDM) in a frequency selective fading channel. If the channel is static and is perfectly known to both the transmitter and the receiver, the water-filling technique with adaptive modulation is known to be optimal. However, for OFDM systems, this requires intensive traffic overheads for reporting channel side information on all subcarriers to the transmitter In this paper, we propose an adaptive modulation and coding scheme for bit-interleaved coded OFDM (BIC-OFDM) for downlink packet transmissions with reduced feedback information. To minimize the feedback information, we employ a rate adaptation method based on the OFDM symbol rather than on each subcarrier. To illustrate the performance gap between the optimal water-filling and the proposed scheme, we will compare cutoff rates for both schemes. It is shown that the loss is less than 2dB while the proposed scheme significantly reduces the feedback payloads. Also, the OFDM system in multiuser environment with subcarrier grouping is considered. It is shown that by exploiting multiuser diversity the throughput of the proposed scheme approaches the channel outage capacity as the number of users and the number of subcarrier groups increase.

• Journal of the Korea Institute of Building Construction
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• v.10 no.1
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• pp.199-212
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• 2010

To establish an infrastructure for technology and information in the domestic construction industry, several construction regulations pertaining to construction information have been institutionalized. However, there are major problems with the domestic information classification system, earned value management (EVM) and project management information system (PMIS). In particular, the functions of the current PMIS have consisted of a builder-oriented system, and as EVM is not applied to PMIS, the functions of reporting, analysis and forecast for owners are lacking. Moreover, owners cannot confirm information on construction schedule and cost in real time due to the differences between the EVM and PMIS operation systems. The purpose of this study is to provide a framework that is capable of operating PMIS efficiently under an e-business environment, by providing a proposal on how to establish a work breakdown structure (WBS) and an EVM - PMIS integration model, so that PMIS may provide the function of EVM, and stakeholders may have all information in common. At the core of EVM - PMIS integration is the idea that EVM and PMIS have the same operation system, in order to be an activity-based system. The principle of the integration is data integration, in which the information field of an activity is connected with the field of a relational database table consisting of sub-modules for the schedule and cost management function of PMIS using a relational database management system. Therefore, the planned value (PV), cost value (CV), actual cost (AC), schedule variance (SV), schedule performance index (SPI), cost variance (CV) and cost performance index (CPI) of an activity are connected with the field of the relational database table for the schedule and cost sub-modules of PMIS.

• Journal of the Korean Chemical Society
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• v.63 no.3
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• pp.166-182
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• 2019

This study examined teachers' difficulties that they encountered free semester science assessment and their problem solutions. Fifteen science teachers who had experiences of free semester teaching and assessment were selected by convenience sampling in this study. The participant teachers mentioned difficulties of accurate scoring in student self/peer assessment and suggested solutions of providing studetns with detailed assessment criteria and opportunities to practice assessment. The participant teachers mentioned a lack of objective assessment criteria for affective domain and suggested solutions of providing criteria prior to assessment and developing assessment framework. The participant teachers mentioned a lack of assessment tools and references for perforamnce assesement. The participant teachers mentioned difficulties of a large teacherstudent ratio for providng feedbacks to students and suggested solutions of decreasing teacher-student ratio and teaching load. The participant teachers mentioned difficulties of identifying student characteristics for assessment reporting and suggested solutions of decreaing teacher work load. The participant teachers mentioned a lack of teacher understanding of process based assessment and inactive attitude to performance assessment and suggested solutions of professional learning community and improving teacher perceptions on performance assessment. The participant teachers mentioned difficulties of a large teacher-student ratio and a lack of time for implementing assessment methods that they learned from professional development programs. With both teacher self-efforts and systematic support, these problems would be solved and success of free semester assessment would be achieved.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.3037-3048
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• 2018

This study tried to test the result of recent study reporting that there is no the effect of cross-subsidization by applying it to the Korean banks. Besides, the study also did the research to test the previous study that diversification toward non-interest operating sector is related with the motivation of reduction of bank risk. Main results are as follows. First, there is the effect of cross-subsidization between non-interest operating sector and interest one. The higher non-interest profit to total asset is, the lower loan growth and provision to total loan are. Second, the effect of cross-subsidization is related with the fee revenue to operating revenue rather than the fiduciary revenue to operating revenue because high fee revenue results in shrinking the lending business. Third, diversification toward non-interest sector is associated with reducing risk, and risk is not increased when the high performance of non-interest sector is occurred. This evidence is not line with DeYoung, Torna (2013) arguing that non-interest operating activities lead to increasing risk. Finally, Korean banks have to expand the activities in non-interesting sector focusing on boosting fee revenue to increase the effect of cross-subsidization against the possibility of cutting net interest margin.

• Investigative Magnetic Resonance Imaging
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• v.25 no.4
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• pp.313-322
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• 2021

Purpose: To find diagnostic image features, to compare diagnostic performance of multiphase CT versus gadoxetic acid disodium-enhanced MRI (GAD-MRI), and to evaluate the impact of analyzing Liver Imaging Reporting and Data System (LI-RADS) imaging features, for distinguishing combined hepatocellular-cholangiocarcinoma (CHC) from hepatocellular carcinoma (HCC). Materials and Methods: Ninety-six patients with pathologically proven CHC (n = 48) or HCC (n = 48), diagnosed June 2008 to May 2018 were retrospectively analyzed in random order by three radiologists with different experience levels. In the first analysis, the readers independently determined the probability of CHC based on their own knowledge and experiences. In the second analysis, they evaluated imaging features defined in LI-RADS 2018. Area under the curve (AUC) values for CHC diagnosis were compared between CT and MRI, and between the first and second analyses. Interobserver agreement was assessed using Cohen's weighted κ values. Results: Targetoid LR-M image features showed better specificities and positive predictive values (PPV) than the others. Among them, rim arterial phase hyperenhancement had the highest specificity and PPV. Average sensitivity, specificity, and AUC values were higher for MRI than for CT in both the first (P = 0.008, 0.005, 0.002, respectively) and second (P = 0.017, 0.026, 0.036) analyses. Interobserver agreements were higher for MRI in both analyses (κ = 0.307 for CT, κ = 0.332 for MRI in the first analysis; κ = 0.467 for CT, κ = 0.531 for MRI in the second analysis), with greater agreement in the second analysis for both CT (P = 0.001) and MRI (P < 0.001). Conclusion: Rim arterial phase hyperenhancement on GAD-MRI can be a good indicator suggesting CHC more than HCC. GAD-MRI may provide greater accuracy than CT for distinguishing CHC from HCC. Interobserver agreement can be improved for both CT and MRI by analyzing LI-RADS imaging features.

• 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.

• Journal of Intelligence and Information Systems
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• v.28 no.4
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• pp.211-227
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• 2022

Illegal gambling through online gambling sites has become a significant social problem. The development of Internet technology and the spread of smartphones have led to the proliferation of illegal gambling sites, so now illegal online gambling has become accessible to anyone. In order to mitigate its negative effect, the Korean government is trying to detect illegal gambling sites by using self-monitoring agents or reporting systems such as 'Nuricops.' However, it is difficult to detect all illegal sites due to limitations such as a lack of staffing. Accordingly, several scholars have proposed intelligent illegal gambling site detection techniques. Xu et al. (2019) found that fake or illegal websites generally have unique features in the HTML tag structure. It implies that the HTML tag structure can be important for detecting illegal sites. However, prior studies to improve the model's performance by utilizing the HTML tag structure in the illegal site detection model are rare. Against this background, our study aimed to improve the model's performance by utilizing the HTML tag structure and proposes Tag2Vec, a modified version of Doc2Vec, as a methodology to vectorize the HTML tag structure properly. To validate the proposed model, we perform the empirical analysis using a data set consisting of the list of harmful sites from 'The Cheat' and normal sites through Google search. As a result, it was confirmed that the Tag2Vec-based detection model proposed in this study showed better classification accuracy, recall, and F1_Score than the URL-based detection model-a comparative model. The proposed model of this study is expected to be effectively utilized to improve the health of our society through intelligent technology.