• Journal of Oral Medicine and Pain
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• v.44 no.3
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• pp.92-102
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• 2019

Purpose: To investigate the masticatory function of patients with different temporomandibular disorders (TMD) phenotypes, and to explore the risk factors for the masticatory function of TMD patients among multiple biopsychosocial variables using patient-reported outcomes (PROs). Methods: Clinical features and TMD diagnoses of 250 cases were investigated by reviewing medical records. Psychosocial factors were evaluated using four questionnaires representing pain severity and pain interference (Brief Pain Inventory), pain catastrophizing (Pain Catastrophizing Scale, PCS), psychological distress (Symptom Check List-90-Revised, SCL-90R) and kinesiophobia (Tampa Scale for Kinesiophobia for Temporomandibular Disorders, TSK-TMD). Masticatory function, as a dependent variable, was determined using the Jaw Functional Limitation Scale (JFLS). Kruskal-Wallis test and Spearman's rank correlation were used for analyses. Results: A total of 145 cases were included and classified into four subgroups including group 1: TMD with internal derangement without pain (n=14), group 2: TMD with muscle pain (n=32), group 3: TMD with joint pain (n=60) and group 4: TMD with muscle-joint combined pain (n=39). Pain severity (p=0.001) and interference (p=0.022) were the highest in group 2, but the mean global score of JFLS was the highest in group 3, followed by group 4, group 2, and group 1 (p=0.013). Pain severity, pain interference, the mean global score of PCS and the mean global score of TSK-TMD showed significant and moderate correlation with the mean global score of JFLS. All subdimensions and the global severity index of SCL-90R had significant, but weak correlations with all scores of JFLS. Conclusions: The results suggest that masticatory functional limitation depends on the TMD phenotypes. Among the various PROs, pain perception, pain catastrophizing and kinesiophobia seem to be more influential risk factors on jaw function than psychological distress, such as depression and anxiety.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.285-291
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• 2019

This study was conducted to identify the factors influencing health-related quality of life of urinary incontinent elderly women. The Korea National Health and Nutrition Examination Survey (KNHANES) conducted by the Korea Centers for Disease Control and Prevention (KCDC) was used as baseline data to evaluate how activity limitation, depression experience and subjective health perception influence the health-related quality of life of urinary incontinent elderly women. The urinary incontinent elderly women differed significantly in terms of activity limitation, depression experience, subjective health perception influence and health-related quality of life compared to elderly women without incontinence. In contrast, income and education were not correlated with either of the aforementioned groups. The subjective health perception was identified as the only factor influencing the health-related quality of life of urinary incontinent elderly women. The results of this study will serve as basic data for positive treatment promotion and development of assessment programs for incontinence patients who recognize incontinence symptoms as part of the aging process and are therefore unwilling to receive care.

• Clinical and Experimental Reproductive Medicine
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• v.46 no.1
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• pp.36-40
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• 2019

A viable spermatozoon is a prerequisite for fertilization in intracytoplasmic sperm injection (ICSI). Thus, it is crucial to select viable but immotile spermatozoa on the day of ICSI. We report conflicting results in the identification of viable but immotile spermatozoa between the eosin-nigrosin staining and the laser test, which resulted in confusion for embryologists during assisted reproductive technology (ART). Three patients' semen samples that showed no motile spermatozoa are described in this report. To identify viable spermatozoa, we used both the eosin-nigrosin test and the laser test for each sample, and repeated the semen analysis twice in each patient. Viable but immotile spermatozoa selected by the laser test were used for ICSI. Viable spermatozoa were detected by both the eosin-nigrosin and laser tests in two patients (case 1, 95.00% vs. 24.21% and 92.68% vs. 22.22%; case 2, 41.18% vs. 23.48% and 39.81% vs. 22.52%), indicating consistent results between the two methods. In the third patient, the eosin-nigrosin test yielded viability rates of 20.75% and 19.14%, while the result of the laser test was 0%. Thus, testicular aspiration was performed to collect viable sperm from this patient. Normal fertilization was achieved after the injection of viable but immotile spermatozoa selected from these patients by the laser test, resulting in the birth of two healthy babies. Our study documents a case where the eosin-nigrosin test showed a limitation in identifying viable but immotile spermatozoa for ART, while the laser test may overcome this limitation. Larger samples may be required to corroborate the clinical value of the laser test.

• Nuclear Engineering and Technology
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• v.53 no.6
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• pp.1821-1833
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• 2021

The gas-liquid counter-current flow limitation (CCFL) is closely related to efficient and safety operation of many equipment in industrial cycle. Air-water countercurrent flow experiments were performed in a tube with diameter of 25 mm to understand the triggering mechanism of CCFL. A parallel electrode probe was utilized to measure film thickness whereby the time domain and frequency domain characteristics of liquid film was obtained. The amplitude of the interface wave is small at low liquid flow rate while it becomes large at high liquid flow rate after being disturbed by the airflow. The spectral characteristic curve shows a peak-shaped distribution. The crest exists between 0 and 10 Hz and the amplitude decreases with the frequency increase. The analysis of visual observation and characteristic of film thickness indicate that two flooding mechanisms were identified at low and high liquid flow rate, respectively. At low liquid flow rate, the interfacial waves upward propagation is responsible for the formation of CCFL onset. While flooding at high liquid flow rate takes place as a direct consequence of the liquid bridging in tube due to the turbulent flow pattern. Moreover, it is believed that there is a transition region between the low and high liquid flow rate.

• 한국사회정책
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• v.24 no.4
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• pp.151-184
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• 2017

The purpose of this study is to investigate the development process and current status of income maintenance policies after the financial crisis, to sort out key issues or problems, and to explore future plans or directions that can overcome the limitation. In order to develop intensive argument, the scope of research is limited to the National Pension, Basic Pension, and the National Basic Livelihood Security System. The research also focused on two values of the 'universalism' and the 'adequacy' based on the 'SPF(social protection floor)' in the overall narrative process. Additionally, this paper briefly summarized the related contents released by the Moon Jae-in Government and presented an affirmative strategy and a transformational strategy centered on social allowance and basic income respectively, to establish an integrated income guarantee scheme. Although some improvements to the present system are also required, it is an effort to expand the practical effect of social benefits through the full and comprehensive reform of benefit structure and method.

• Journal of Internet of Things and Convergence
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• v.7 no.1
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• pp.1-7
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• 2021

The IoT market continues to expand and grow, but the security threat to IoT devices is also increasing. However, it is difficult to apply the security technology applied to the existing system to IoT devices that have a problem of resource limitation. Therefore, in this paper, we present a service that can improve the security of IoT devices by presenting authentication and lightweight cryptographic algorithms that can reduce the overhead of applying security features, taking into account the nature of resource limitations of IoT devices. We want to apply these service to home network IoT equipment to provide security. The authentication and lightweight cryptographic algorithm application protocols presented in this paper have secured the safety of the service through the use of LEA encryption algorithms and secret key generation by users, IoT devices and server in the IoT environment. Although there is no difference in speed from randomly generating secret keys in experiments, we verify that the problem of resource limitation of IoT devices can be solved by additionally not applying logic for secret key sharing to IoT devices.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.6
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• pp.1043-1052
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• 2020

Signature-based malicious code detection methods share a common limitation; it is very hard to detect modified malicious codes or new malware utilizing zero-day vulnerabilities. To overcome this limitation, many studies are actively carried out to classify malicious codes using N-gram. Although they can detect malicious codes with high accuracy, it is difficult to identify malicious codes that uses very short codes such as Spectre. We propose a function level N-gram comparison algorithm to effectively identify the Spectre binary. To test the validity of this algorithm, we built N-gram data sets from 165 normal binaries and 25 malignant binaries. When we used Random Forest models, the model performance experiments identified Spectre malicious functions with 99.99% accuracy and its f1-score was 92%.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.419-429
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• 2021

The purpose of this study is to investigate the effects of service guarantees of tourist hotels on employees' perception of role clarity and customer orientation. Specifically, this study analyzed how the employees' perception of role clarity as a parameter, with the employees' reliability, guarantee-related communication, guarantee limitation, and organizational support as independent variables, affected the dependent variable, customer orientation. As a result of empirical analysis of employees in the first grade hotel in Seoul, it was analyzed that the higher the reliability of employees in service guarantee, the higher the communication and organizational support in the organization related to guarantee work, the higher the role clarity and perception level of employees. The higher the reliability, guarantee limitation and organizational support level of guarantee, the higher the customer orientation, but the guarantee-related communication did not show significant influence. The perception degree of role clarity of employees has a significant effect on customer orientation. According to those results of this analysis, this study examined the influence of each configuration of service guarantee of tourist hotel employees on customer orientation, and presented various academic and practical implications.

• The Korean Journal of Applied Statistics
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• v.35 no.3
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• pp.357-370
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• 2022

In this paper, Tobit and Heckit models are introduced. These models have been used for analyzing censored data. Censoring occurs at a specific point and a large number of observations are distributed with a positive probability at a certain point. Censoring can occur due to observing limitation or exogenous variables. Tobit and Heckit models are used to correct sample selection bias, which can occur when an ordinary linear regression model is fitted to censored data. However, the difference between the two models is not clearly accounted for; hence, they have often been used interchangeably. Therefore, the suitability of the models was validated through simulated data, and demonstrated through real data. As the result, it was confirmed that both Tobit and Heckit models are well-fitted to the data censored due to observing limitation, although Tobit model was fitted parsimoniously. In contrast, only Heckit model is well-fitted to the data censored due to exogenous variables.

• International Journal of Computer Science & Network Security
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• v.22 no.2
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• pp.318-326
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• 2022

Marketing stress testing is a new method of identifying the company's strengths and weaknesses in a turbulent environment. Technically, this is a complex procedure, so it involves artificial intelligence and machine learning. The main problem is currently the development of methodological approaches to the development of the company's digital model, which will provide a framework for machine learning. The aim of the study was to identify and develop an author's approach to the parameterization of the company's business processes for machine learning-based marketing stress testing. This aim provided the company's activities to be considered as a set of elements (business processes, products) and factors that affect them (marketing environment). The article proposes an author's approach to the parameterization of the company's business processes for machine learning-based marketing stress testing. The proposed approach includes four main elements that are subject to parameterization: elements of the company's internal environment, factors of the marketing environment, the company' core competency and factors impacting the company. Matrices for evaluating the results of the work of expert groups to determine the degree of influence of the marketing environment factors were developed. It is proposed to distinguish between mega-level, macro-level, meso-level and micro-level factors depending on the degree of impact on the company. The methodological limitation of the study is that it involves the modelling method as the only one possible at this stage of the study. The implementation limitation is that the proposed approach can only be used if the company plans to use machine learning for marketing stress testing.