• The Journal of the Acoustical Society of Korea
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• v.27 no.7
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• pp.333-341
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• 2008

In this paper, a new interpolation model for the head related transfer function (HRTF) was proposed. In the method herein, we assume that the impulse response of the HRTF for each azimuth angle is given by linear interpolation of the time-delayed neighboring impulse responses of HRTFs. The time delay of the HRTF for each azimuth angle is given by sum of the sound wave propagation time from the ears to the sound source, which can be estimated by using azimuth angle, the physical shape of the underlying head and the distance between the head and sound source, and the refinement time yielding the minimum mean square error. Moreover, in the proposed model, the interpolation intervals were not fixed but varied, which were determined by minimizing the total number of HRTFs while the synthesized signals have no perceptual difference from the original signals in terms of sound location. To validate the usefulness of the proposed interpolation model, the proposed model was applied to the several HRTFs that were obtained from one dummy-head and three human heads. We used the HRTFs that have 5 degree azimuth angle resolution at 0 degree elevation (horizontal plane). The experimental results showed that using only $30\sim40%$ of the original HRTFs were sufficient for producing the signals that have no audible differences from the original ones in terms of sound location.

• Molecules and Cells
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• v.46 no.11
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• pp.688-699
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• 2023

We set up this study to understand the underlying mechanisms of reduced ceramides on immune cells in acute rejection (AR). The concentrations of ceramides and sphingomyelins were measured in the sera from hepatic transplant patients, skin graft mice and hepatocyte transplant mice by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Serum concentrations of C24 ceramide, C24:1 ceramide, C16:0 sphingomyelin, and C18:1 sphingomyelin were lower in liver transplantation (LT) recipients with than without AR. Comparisons with the results of LT patients with infection and cardiac transplant patients with cardiac allograft vasculopathy in humans and in mouse skin graft and hepatocyte transplant models suggested that the reduced C24 and C24:1 ceramides were specifically involved in AR. A ceramide synthase inhibitor, fumonisin B₁ exacerbated allogeneic immune responses in vitro and in vivo, and reduced tolerogenic dendritic cells (tDCs), while increased P3-like plasmacytoid DCs (pDCs) in the draining lymph nodes from allogeneic skin graft mice. The results of mixed lymphocyte reactions with ceranib-2, an inhibitor of ceramidase, and C24 ceramide also support that increasing ceramide concentrations could benefit transplant recipients with AR. The results suggest increasing ceramides as novel therapeutic target for AR, where reduced ceramides were associated with the changes in DC subsets, in particular tDCs.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.2
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• pp.121-131
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• 2024

Purpose : This study aimed to investigate the leisure satisfaction of participants in the Geod-Jyu walking program and to examine the relationship between health promotion behaviors and quality of life. In addition, we investigated the impact of leisure satisfaction with walking among program participants on health promotion behaviors and quality of life. By clarifying these relationships, we aimed to identify factors of leisure satisfaction with walking that could enhance participants' health promotion behaviors and quality of life. Methods : A survey was conducted among 301 participants enrolled in the Geod-Jyu walking program in Chungcheongnam-do, with 288 responses analyzed. Data analysis included Pearson's correlation, confirmatory factor analysis, and multiple regression analysis using SPSS 27.0. Result : Leisure satisfaction exhibited a positive correlation with health promotion behavior (r=.544, p<.01) and quality of life (r=.478, p<.01). Furthermore, health promotion behavior showed a positive correlation with quality of life (r=.636, p<.01). Leisure satisfaction positively influenced quality of life, with physiological satisfaction (β=.16, t=2.32) and relaxation satisfaction (β=.15, t=2.04) emerging as notable contributors. In addition, leisure satisfaction had a significant positive impact on health promotion behaviors, with psychological satisfaction (β=.24, t=3.09) and educational satisfaction (β=.20, t=3.09) playing key roles. Health promotion behavior had a positive impact on quality of life, with all sub variables exhibiting significant positive effects in the following order: self-actualization (β=.24, t=4.16), stress management (β=.22, t=3.97), exercise (β=.22, t=4.05), and health responsibility (β=.12, t=2.14). Conclusion : The findings indicate that factors related to physical and rest satisfaction, as well as health-promoting behaviors facilitated by walking, significantly affected the quality of life among Geod-Jyu participants. Thus, promoting leisure satisfaction and engaging in health-promoting activities through walking can enhance overall well-being. Encouraging participation in the Geod-Jyu walking program is critical for physical and psychological benefits, and for promoting healthier behaviors. Further development of Geod-Jyu is expected to enhance walking satisfaction, promote self-care skills for health management, and positively influence quality of life.

• Journal of Korean Home Economics Education Association
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• v.26 no.4
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• pp.21-34
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• 2014

This study examined the levels of recognition, knowledge, and intake behavior of foods containing caffeine and analyzed the factors affecting amount of caffeine intake to get basic materials for development of educational program for proper intake behavior of foods containing caffeine of high school students in Gyeongbuk region. Of 300 questionnaires that were distributed on December 27, 2013 to February 14, 2014, 255 responses were used for analysis. Frequency distributions, Cronbach's ${\alpha}$, t tests, one-way ANOVA, Pearson's correlation analysis, and regression analysis were conducted by SPSS Windows V.21.0. The mean of the level of concern about foods containing caffeine was 2.76/5.00 points; male and second and third grade students showed lower concern level than female and first grade students. The respondents answered that intake of foods containing caffeine had somewhat harmful effect on health, but it did not much help to refresh and increase concentration. The mean for the percentage of correct answers about knowledge of caffeine was 54.3. Small number of the respondents were advised to reduce intake of caffeine from school teachers or parents. The average of caffeine intake amount was 71.67mg/day; the average for male was 78.98mg/day, whereas for female 61.23mg/day. Almost thirteen percentage of the respondents took caffeine over RDA(Recommended Daily Allowance). According to the result of regression analysis for amount of caffeine intake, grade, BMI, concern about health, perception of whether foods containing caffeine help with refreshment and increase of concentration or not, and experiences of having advice from school teachers to decrease caffeine intake were significant. These results imply that it is necessary for high school students to educate how to take caffeine properly.

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.59-59
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• 2015

Cryptococcus neoformans causes life-threatening meningoencephalitis in humans, but the treatment of cryptococcosis remains challenging. To develop novel therapeutic targets and approaches, signaling cascades controlling pathogenicity of C. neoformans have been extensively studied but the underlying biological regulatory circuits remain elusive, particularly due to the presence of an evolutionarily divergent set of transcription factors (TFs) in this basidiomycetous fungus. In this study, we constructed a high-quality of 322 signature-tagged gene deletion strains for 155 putative TF genes, which were previously predicted using the DNA-binding domain TF database (http://www.transcriptionfactor.org/). We tested in vivo and in vitro phenotypic traits under 32 distinct growth conditions using 322 TF gene deletion strains. At least one phenotypic trait was exhibited by 145 out of 155 TF mutants (93%) and approximately 85% of the TFs (132/155) have been functionally characterized for the first time in this study. Through high-coverage phenome analysis, we discovered myriad novel TFs that play critical roles in growth, differentiation, virulence-factor (melanin, capsule, and urease) formation, stress responses, antifungal drug resistance, and virulence. Large-scale virulence and infectivity assays in insect (Galleria mellonella) and mouse host models identified 34 novel TFs that are critical for pathogenicity. The genotypic and phenotypic data for each TF are available in the C. neoformans TF phenome database (http://tf.cryptococcus.org). In conclusion, our phenome-based functional analysis of the C. neoformans TF mutant library provides key insights into transcriptional networks of basidiomycetous fungi and ubiquitous human fungal pathogens.

• The Korean Journal of Emergency Medical Services
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• v.15 no.3
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• pp.31-44
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• 2011

Purpose : The purpose of emergency medical services(EMS) is to save human lives and assure the completeness of the body in emergency situations. Those who have been qualified on medical practice to perform such treatment as there is the risk of human life and possibility of major physical and mental injuries that could result from the urgency of time and invasiveness inflicted upon the body. In the emergency medical activities, 119 emergency medical technicians mainly perform the task but they are not able to perform such task independently and they are mandatory to receive medical direction. The purpose of this study is to examine the recognition and request for medical direction by 119 emergency medical technicians in order to provide basic information on the development of medical direction program suitable to the characteristics of EMS as well as for the studies on EMS for the sake of efficient operation of pre-hospital EMS. Method : Questionnaire via e-mail was conducted during July 1-31, 2010 for 675 participants who are emergency medical technicians, nurses and other emergency crews in Gyeongbuk. The effective 171 responses were used for the final analysis. In regards to the emergency medical technicians' scope of responsibilities defined in Attached Form 14, Enforcement regulations of EMS, t-test analysis was conducted by using the means and standard deviation of the level of request for medical direction on the scope of responsibilities of Level 1 & Level 2 emergency medical technicians as the scale of medical direction request. The general characteristics, experience result, the reason for necessity, emergency medical technicians & medical director request level, medical direction method, the place of work of the medical director, feedback content and improvement plan request level were analyzed through frequency and percentage. The level of experience in medical direction and necessity were analyzed through ${\chi}^2$ test. Results : In regards to the medical direction experience per qualification, the experience was the highest with 53.3% for Level 1 emergency medical technicians and 80.3% responded that experience was helpful. As for the recognition on the necessity of medical direction, 71.3% responded as "necessary" and it turned out to be the highest of 76.9% in nurses. As for the reason for responding "necessary", the reason for reducing the risk and side-effects from EMS for patients was the largest(75.4%), and the reason of EMS delay due to the request of medical direction was the highest(71.4%) for the reason for responding "not necessary". In regards to the request level of the task scope of emergency medical technicians, injection of certain amount of solution during a state of shock was the highest($3.10{\pm}.96$) for Level 1 emergency rescuers, and the endotracheal intubation was the highest($3.12{\pm}1.03$) for nurses, and the sublingual administration of nitroglycerine(NTG) during chest pain was the highest($2.62{\pm}1.02$) for Level 2 emergency medical technicians, and regulation of heartbeat using AED was the highest($2.76{\pm}.99$) for other emergency crews. For the revitalization of medical direction, the improvement in the capability of EMS(78.9%) was requested from emergency crew, and the ability to evaluate the medical state of patient was the highest(80.1%) in the level of request for medical director. The prehospital and direct medical direction was the highest(60.8%) for medical direction method, and the emergency medical facility was the highest(52.0%) for the placement of medical director, and the evaluation of appropriateness of EMS was the highest(66.1%) for the feedback content, and the reinforcement of emergency crew(emergency medical technicians) personnel was the highest(69.0%) for the improvement plan. Conclusion : The medical direction is an important policy in the prehospital EMS activity because 119 emergency medical technicians agreed the necessity of medical direction and over 80% of those who experienced medical direction said it was helpful. In addition, the simulation training program using algorithm and case study through feedback are necessary in order to enhance the technical capability of ambulance teams on the item of professional EMS with high level of request in the task scope of emergency medical technicians, and recognition of medical direction is the essence of the EMS field. In regards to revitalizing medical direction, the improvement of the task performance capability of 119 emergency medical technicians and medical directors, reinforcement of emergency medical activity personnel, assurance of trust between emergency medical technicians and the emergency physician, and search for professional operation plan of medical direction center are needed to expand the direct medical direction method for possible treatment beforehand through the participation by medical director even at the step in which emergency situation report is received.

• Journal of Life Science
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• v.28 no.2
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• pp.207-215
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• 2018

Inflammatory response and oxidative stress play critical roles in the development and progression of many human diseases. Therefore, a great deal of attention has been focused on finding functional materials that can control inflammation and oxidative stress simultaneously. The purpose of this study was to investigate the effects of Socheongja and Socheong 2, Korean black seed coat soybean varieties, on the inflammatory and oxidative stress induced by lipopolysaccharide (LPS) in RAW 264.7 macrophages. Our data indicated that the extracts of Socheongja (SCJ) and Socheong 2 (SC2) significantly suppressed LPS-induced production of nitrite oxide (NO) and prostaglandin $E_2$, key pro-inflammatory mediators, by suppressing the expression of inducible NO synthase and cyclooxygenase-2. It was also found that SCJ and SC2 reduced the LPS-induced secretion of pro-inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ and $interleukin-1{\beta}$, which was concomitant with a decrease in the protein levels. In addition, SCJ and SC2 markedly diminished LPS-stimulated intracellular reactive oxygen species accumulation, and effectively enhanced nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase (HO)-1 expression. Furthermore, LPS-induced activation of mitogen-activated protein kinases (MAPKs) was abrogated by SCJ and SC2. Taken together, these data suggest that SCJ and SC2 may offer protective roles against LPS-induced inflammatory and oxidative responses in RAW 264.7 macrophages through attenuating MAPKs pathway, and these effects are mediated, at least in part, through activating Nrf2/HO-1 pathway. Given these results, we propose that SCJ and SC2 have therapeutic potential in the treatment of inflammatory and oxidative disorders caused by over-activation of macrophages.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2007.05a
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• pp.234-245
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• 2007

The empirical studies on the implementation of data warehousing systems (DWS) are lacking while there exist a number of studies on the implementation of IS. This study intends to examine the factors affecting the implementation success of DWS. The study adopts the empirical analysis of the sample of 112 responses from DWS practitioners. The study results suggest several implications for researchers and practitioners. First, when the support from top management becomes great, the implementation success of DWS in organizational aspects is more likely. When the support from top management exists, users are more likely to be encouraged to use DWS, and organizational resistance to use DWS is well coped with increasing the possibility of implementation success of DWS. The support of resource increases the implementation success of DWS in project aspects while it is not significantly related to the implementation success of DWS in organizational aspects. The support of funds, human resources, and other efforts enhances the possibility of successful implementation of project; the project does not exceed the time and resource budgets and meet the functional requirements. The effect of resource support, however, is not significantly related to the organizational success. The user involvement in systems implementation affects the implementation success of DWS in organizational and project aspects. The success of DWS implementation is significantly related to the users' commitment to the project and the proactive involvement in the implementation tasks. users' task. The observation of the behaviors of competitors which possibly increases data quality does not affect the implementation success of DWS. This indicates that the quality of data such as data consistency and accuracy is not ensured through the understanding of the behaviors of competitors, and this does not affect the data integration and the successful implementation of DWS projects. The prototyping for the DWS implementation positively affects the implementation success of DWS. This indicates that the extent of understanding requirements and the communication among project members increases the implementation success of DWS. Developing the prototypes for DWS ensures the acquirement of accurate or integrated data, the flexible processing of data, and the adaptation into new organizational conditions. The extent of consulting activities in DWS projects increases the implementation success of DWS in project aspects. The continuous support for consulting activities and technology transfer enhances the adherence to the project schedule preventing the exceeding use of project budget and ensuring the implementation of intended system functions; this ultimately leads to the successful implementation of DWS projects. The research hypothesis that the capability of project teams affects the implementation success of DWS is rejected. The technical ability of team members and human relationship skills themselves do not affect the successful implementation of DWS projects. The quality of the system which provided data to DWS affects the implementation success of DWS in technical aspects. The standardization of data definition and the commitment to the technical standard increase the possibility of overcoming the technical problems of DWS. Further, the development technology of DWS affects the implementation success of DWS. The hardware, software, implementation methodology, and implementation tools contribute to effective integration and classification of data in various forms. In addition, the implementation success of DWS in organizational and project aspects increases the data quality and system quality of DWS while the implementation success of DWS in technical aspects does not affect the data quality and system quality of DWS. The data and systems quality increases the effective processing of individual tasks, and reduces the decision making times and efforts enhancing the perceived benefits of DWS.

• Journal of Intelligence and Information Systems
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• v.21 no.2
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• pp.1-18
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• 2015

Collaborative filtering(CF) algorithm has been popularly used for recommender systems in both academic and practical applications. A general CF system compares users based on how similar they are, and creates recommendation results with the items favored by other people with similar tastes. Thus, it is very important for CF to measure the similarities between users because the recommendation quality depends on it. In most cases, users' explicit numeric ratings of items(i.e. quantitative information) have only been used to calculate the similarities between users in CF. However, several studies indicated that qualitative information such as user's reviews on the items may contribute to measure these similarities more accurately. Considering that a lot of people are likely to share their honest opinion on the items they purchased recently due to the advent of the Web 2.0, user's reviews can be regarded as the informative source for identifying user's preference with accuracy. Under this background, this study proposes a new hybrid recommender system that combines with users' review mining. Our proposed system is based on conventional memory-based CF, but it is designed to use both user's numeric ratings and his/her text reviews on the items when calculating similarities between users. In specific, our system creates not only user-item rating matrix, but also user-item review term matrix. Then, it calculates rating similarity and review similarity from each matrix, and calculates the final user-to-user similarity based on these two similarities(i.e. rating and review similarities). As the methods for calculating review similarity between users, we proposed two alternatives - one is to use the frequency of the commonly used terms, and the other one is to use the sum of the importance weights of the commonly used terms in users' review. In the case of the importance weights of terms, we proposed the use of average TF-IDF(Term Frequency - Inverse Document Frequency) weights. To validate the applicability of the proposed system, we applied it to the implementation of a recommender system for smartphone applications (hereafter, app). At present, over a million apps are offered in each app stores operated by Google and Apple. Due to this information overload, users have difficulty in selecting proper apps that they really want. Furthermore, app store operators like Google and Apple have cumulated huge amount of users' reviews on apps until now. Thus, we chose smartphone app stores as the application domain of our system. In order to collect the experimental data set, we built and operated a Web-based data collection system for about two weeks. As a result, we could obtain 1,246 valid responses(ratings and reviews) from 78 users. The experimental system was implemented using Microsoft Visual Basic for Applications(VBA) and SAS Text Miner. And, to avoid distortion due to human intervention, we did not adopt any refining works by human during the user's review mining process. To examine the effectiveness of the proposed system, we compared its performance to the performance of conventional CF system. The performances of recommender systems were evaluated by using average MAE(mean absolute error). The experimental results showed that our proposed system(MAE = 0.7867 ~ 0.7881) slightly outperformed a conventional CF system(MAE = 0.7939). Also, they showed that the calculation of review similarity between users based on the TF-IDF weights(MAE = 0.7867) leaded to better recommendation accuracy than the calculation based on the frequency of the commonly used terms in reviews(MAE = 0.7881). The results from paired samples t-test presented that our proposed system with review similarity calculation using the frequency of the commonly used terms outperformed conventional CF system with 10% statistical significance level. Our study sheds a light on the application of users' review information for facilitating electronic commerce by recommending proper items to users.

• Korean Journal of Cognitive Science
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• v.27 no.4
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• pp.501-539
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• 2016

The human mind is a self-evolving system that develops along a multidimensional hierarchical pathway in response to traumatic stimulus. In absence of trauma, a mind integrated in conflict-free state is called monistic. When the monistic mind responses to a traumatic stimulus, a response polarity forms toward stimulus polarity within the mind, turning it into a bipartite structure. Dialectical interaction between the two opposites, originating from their incompatibility, creates a new third polarity in the upper dimension. Thereby, the mind turns into a trinity structure. When the interaction among the three polarities becomes optimized, the plasticity of the mind gets maximized into the "far-from-equilibrium state," and the function of three polarities is synchronized. Through this recalibration, the mind returns back to its monistic structure. If the mind with the recurred monistic structure responds to another traumatic stimulus, this cycle of hierarchical transformation repeats itself in this cyclical and fractal growth process through synchronization of basic trinity system. Applying this concept to the process of post-traumatic growth (PTG), this paper explores how the mind transforms traumatic experiences into PTG and proposes a 'PTG Clock' that shows a fundamental sequence in the development of the human mind. The PTG Clock consists of seven hierarchical phases, and each of the first six phases has two opposite sub-phases: shocked/numbed, feared/intrusive, paranoid/avoidant, obsessional/explosive, dependent/depressive, and meaningless/searching for meaning. The seventh, the synchronization phase, completes one cycle of the mind's transformation, realizing a grand trinity system, where the mind synchronizes its biological, social, and existential dimensions. At that point, the mind becomes more susceptible to not only the stimulus of its own traumatic experience but also the pain of others. Thereby, the PTG Clock sets out on a journey to another cycle of transformation in higher dimensions. The validity of this transformational process for the PTG Clock will be examined by comparing it to Horowitz's theory of stress response syndrome.