• Progress in Medical Physics
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• v.23 no.4
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• pp.252-260
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• 2012

The reduction of radiation dose from x-ray is a main concern in computed tomography (CT) imaging due to the side-effect of the dose on human body. Recently, the various methods for dose reduction have been studied in CT and one of the method is a iterative reconstruction based on total variation (TV) minimization at few-views data. In this paper, we evaluated the image quality between total variation (TV) minimization algorithm and Feldkam-Davis-kress (FDK) algorithm in micro computed tomography (CT). To evaluate the effect of TV minimization algorithm, we produced a cylindrical phantom including contrast media, water, air inserts. We can acquire maximum 400 projection views per rotation of the x-ray tube and detector. 20, 50, 90, 180 projection data were chosen for evaluating the level of image restoration by TV minimization. The phantom and mouse image reconstructed with FDK algorithm at 400 projection data used as a reference image for comparing with TV minimization and FDK algorithm at few-views. Contrast-to-noise ratio (CNR), Universal quality index (UQI) were used as a image evaluation metric. When projection data are not insufficient, our results show that the image quality of reconstructed with TV minimization is similar to reconstructed image with FDK at 400 view. In the cylindrical phantom study, the CNR of TV image was 5.86, FDK image was 5.65 and FDK-reference was 5.98 at 90-views. The CNR of TV image 0.21 higher than FDK image CNR at 90-views. UQI of TV image was 0.99 and FDK image was 0.81 at 90-views. where, the number of projection is 90, the UQI of TV image 0.18 higher than FDK image at 90-views. In the mouse study UQI of TV image was 0.91, FDK was 0.83 at 90-views. the UQI of TV image 0.08 higher than FDK image at 90-views. In cylindrical phantom image and mouse image study, TV minimization algorithm shows the best performance in artifact reduction and preserving edges at few view data. Therefore, TV minimization can potentially be expected to reduce patient dose in clinics.

• Sijohaknonchong
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• v.44
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• pp.105-138
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• 2016

Recently with the research function, "XML Digital collection of Sijo Texts in the Period of Modern Enlightenment" DB data is being provided through the Korean Research Memory (http://www.krm.or.kr) and the foundation for the constructing the contents of Sijo Texts in the Period of Modern Enlightenment has been laid. In this paper, by reviewing the characteristics and problems of Digital collection of Sijo Texts in the Period of Modern Enlightenment and searching for the improvement, I tried to find a way to make it into the content. This database has the primary meaning in the integrating and glancing at the vast amounts of Sijo in the Period of Modern Enlightenment to reaching 12,500 pieces. In addition, it is the first Sijo data base which is provide the variety of search features according to literature, name of poet, title of work, original text, per period, and etc. However, this database has the limits to verifying the overall aspects of the Sijo in the Period of Modern Enlightenment. The title and original text, which is written in the archaic word or Chinese character, could not be searched, because the standard type text of modern language is not formatted. And also the works and the individual Sijo works released after 1945 were missing in the database. It is inconvenient to extract the datum according to the poet, because poets are marked in the various ways such as one's real name, nom de plume and etc. To solve this kind of problems and improve the utilization of the database, I proposed the providing the standard type text of modern language, giving the index terms about content, providing the information on the work format and etc. Furthermore, if the Sijo database in the Period of Modern Enlightenment which is prepared the character of the Sijo Culture Information System could be built, it could be connected with the academic, educational contents. For the specific plan, I suggested as follow, - learning support materials for the Modern history and the national territory recognition on the Modern Age - source materials for studying indigenous animals and plants characters creating the commercial characters - applicability as the Sijo learning tool such as Sijo Game.

• Journal of the Korea Society of Computer and Information
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• v.16 no.7
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• pp.1-11
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• 2011

Many researchers have studied on the methods to improve the processor performance. However, high integrated semiconductor technology for improving the processor performance causes many problems such as battery life, high power density, hotspot, etc. Especially, as hotspot has critical impact on the reliability of chip, thermal problems should be considered together with performance and power consumption when designing high-performance processors. To alleviate the thermal problems of processors, there have been various researches. In the past, mechanical cooling methods have been used to control the temperature of processors. However, up-to-date microprocessors causes severe thermal problems, resulting in increased cooling cost. Therefore, recent studies have focused on architecture-level thermal-aware design techniques than mechanical cooling methods. Even though architecture-level thermal-aware design techniques are efficient for reducing the temperature of processors, they cause performance degradation inevitably. Therefore, if the mechanical cooling methods can manage the thermal problems of processors efficiently, the performance can be improved by reducing the performance degradation due to architecture-level thermal-aware design techniques such as dynamic thermal management. In this paper, we analyze the cooling efficiency of high-performance multicore processors according to mechanical cooling methods. According to our experiments using air cooler and liquid cooler, the liquid cooler consumes more power than the air cooler whereas it reduces the temperature more efficiently. Especially, the cost for reducing $1^{\circ}C$ is varied by the environments. Therefore, if the mechanical cooling methods can be used appropriately, the temperature of high-performance processors can be managed more efficiently.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.491-496
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• 2006

Antimicrobial activity of 18 different traditional medicinal herbs extracts against Staphylococcus aureus was determined by a paper disc method. The Prunella vulgaris, Caesalpinia sappan and Rhus javanica extracts in 5 mg/ml, Poncirus trifoliata, Lonicera japonica and Seutellaria baicalensis extracts in 10 mg/ml and Schizandra chinensis, Alpinia katsumadai, Siegesbeckia orientalis extracts in 30 mg/ml showed a significant antimicrobial activity against Staphylococcus aureus. Minimum inhibitory concentrations of medicinal herbs extracts were in the range of $1{\sim}34\;mg/ml$ and $1{\sim}46\;mg/ml$, in the case of MeOH extracts and EtOH extracts, respectively. In addition, the antimicrobial activity of each solvent fraction was most significant with EtOAc layer. Optical density at 620nm after 24 hours incubation of Staphylococcus aureus in the presence of 100, 300 or 500 ppm of Caesalpinia sappan extract ranged from 0.02 to 0.03 compared to 0.4 in the absence of Caesalpinia sappan extract, indicating that growth of Staphylococcus aureus was significantly inhibited within 24 hours by the addition of at least 100 ppm of Caesalpinia sappan extract. Optical density at 620 nm after 24 hours incubation of Staphylococcus aureus in the presence of 300 ppm of Rhus javanica extract ranged from 0.02 to 0.03 compared to 0.4 in the absence of Rhus javanica extract, indicating that growth of Staphylococcus aureus was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Rhus javanica extract. Optical density at 620 nm after 24 hours incubation of Staphylococcus aureus in the presence of 300 ppm of Seutellaria baicalensis extract ranged from 0.02 to 0.07 compared to 0.4 in the absence of Seutellaria baicalensis extract, indicating that growth of Staphylococcus aureus was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Seutellaria baicalensis extract. In conclusion, these findings suggest that extracts from medicinal herbs may play important roles for antimicrobial activities against Staphylococcus aureus.

• International Commerce and Information Review
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• v.13 no.4
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• pp.177-201
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• 2011

Myanmar had fallen behind other southeast asian nations since Burmese way to Socialism settled down. However, historically second election in Myanmar hold in 2011 and dramatic changes in areas such as Special Economic Zone announcement, the very huge inflows of foreign direct investment in a year of 2009, the infrastructure building projects, a permit of the right to strike for Labour Organization in Myanmar etc. Particularly, Foreign investments and trade with neighbouring countries are actively growing and also with Korea. But investments of Korea in Myanmar relatively are not diversity, with limited sectors such as mining and sewing manufacturing. In this point of view, this paper is trying to make implications for strategies of entry and investments of Korea in Myanmar by using previous papers related to Myanmar economies, trade and foreign investments with updated statistical data. The implications for Korea is that recently Myanmar economy is in its early stages of development. Although it can occur huge demand of railway, road, communications and constructions related to social infrastructures essentially needed for development of a country, these sectors relatively need huge investments. On the other hands, textile and sewing industry relatively need smaller investments in which investors can utilize low labour cost and a position for export to third countries. But those firms which set up for those purpose in Myanmar might have trouble creating domestic markets in future. Moreover, due to demand which occur in the early stage of growth in Myanmar, trade volume tend to increase and trading is also possible to invest but Myanmar still have lots of problems with infrastructure such as road and logistics and we need to make pre-survey for the costs and benefits of our products Finally, Myanmar government is trying to promote and encourage some of industries such as export-oriented industry, import substitution industry and labour-intensive industry. It can also means they will accumulate capital which can be sources for Myanmar economic growth.

• Journal of agricultural medicine and community health
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• v.31 no.2
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• pp.145-156
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• 2006

Objectives: Health behaviors are related to each other, or they may be essentially dependent upon each other. Hence the overall health behaviors of a given population could be better described in terms of health lifestyle patterns. This paper tried to classify such patterns in a sample population and suggest the socioeconomic and demographic characteristics of each groups. Methods: A sample population comprised of 2,775 adults who reported their health behaviors in a public health survey were classified according to their smoking, drinking, diet, and exercise related pattern of behaviors. Clustering analysis was used to classify them. Results: Six health lifestyle patterns were identified. Individuals in the passive lifestyle cluster (48.3%) had no active health promoting activities, but did avoid risk taking health behaviors. 24.8% of the sample (Health promoting lifestyle) had an overall healthy lifestyle. 13.5% of the sample were in the smoking cluster, and 8.4% were in the alcohol drinking cluster. The hedonic lifestyle (4.5%) was characterized by heavy smoking, alcohol drinking and poor diet and exercise. 0.7% of the sample (Smoking-Drinking lifestyle) had heavy smoking and drinking, but good diet and exercise. Each group could be characterized by sex, age, and income. Conclusions: A population sample of Seoul adults were successfully clustered into six health lifestyles. The socioeconomic and demographic characteristics were suggested for the characterization of the each health lifestyle groups. We can approach to a certain target population with specific strategy.

• Management & Information Systems Review
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• v.31 no.4
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• pp.237-260
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• 2012

Purposes of this paper are focused on researching that employees in small and medium-sized construction company embraced green growth policy by Korean government's strong will and they have try to improve it to take advantage of strengths. Specifically, the purpose of this study includes: Firstly, to examine the effects of employee's cognition of green growth policy and their organizational commitment. Secondly, to examine the mediating and moderating effect of the policy trust and company trust between employee's cognition of green growth policy and organizational commitment. In addition, th examine the facilitating effect of employee's self-efficacy between company trust and organizational commitment. In order to verify the relationship, moderating and mediating effects, data were collected from 168 individuals in 19 small and medium sized company to test theoretical model and its hypotheses. Findings are as followed: first, the relationship between the cognition of green growth policy and organizational commitment is positively related. Second, the employee's company trust played as a partial mediator and moderator on the relationship between cognition of green growth policy and organizational commitment. Finally, employee's self-efficacy also played as a partial mediator on the relationship between company trust and organizational commitment. This study contributes to deepen our understanding of employee's organizational commitment by suggesting an alternative theoretical model regarding how the cognition of green growth policy and organizational commitment work to relate employee's company trust, and how the company trust and organizational commitment work to facilitate employee's self-efficacy. These results reveal that the study contributed to combining variables of employee's cognition of green growth policy, company trust, self-efficacy and organizational commitment, and expanded it.

• 한국지구물리탐사학회:학술대회논문집
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• 1999.08a
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• pp.137-155
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• 1999

Recently, Televiewer(Borehole Acoustic Scanner(Televiewer)) has come to be widely used specially for the general engineering construction design. The Televiewer tool using a focussed acoustic beam is to detect the amplitude and traveltime of each reflected acoustic signal at the wall, resulting in the amplitude- and traveltime image respectively. Fractures can be well detected, because they easily scatter the acoustic energy due to the highly narrow beam. In addition, the drilling work will rough the borehole wall so that the acoustic energy can be scattered simply due to the roughness of the wall. Thus, the amplitude level can be directed associated with the elastic properties(impedance) and the hardness of the rock as well. Meanwhile, the traveltime image provides an information about the borehole shape and can be converted to a high precision 3D caliper log(max. 288 arms). In this paper, based on the high resolution of Televiewer images, general evaluation methods are illustrated to derive very reliable rock parameters.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1981.05a
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• pp.3.2-3
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• 1981

This paper was attemped to analize 55 cases of fiberoptic bronchoscopy during period of 3 years from Feb. 1978 till Feb. 1981 in Chung Ang University hospital. The results were as follow; 1) In age distribution; Most common age group was 5th decade (15 cases, 27.2%) and the other age groups showed relatively even distribution. 2) The ratio of male to female was 3 to 1. 3) The chief complaints were presented in following order; cough (52%), hemoptysis(25%), dyspnea(23.6%), chest pain(18%), chest disomfort(9%). 4) Direct smear of bronchoscopic aspiration material; Not found 33 cases (60%) were most common finding. In the founded bacteria Gram positive cocci 2 cases (3.6%), Gram negative cocci 2 cases (3.6%), Gram positive bacilli 1 cases (1.8%), Gram negativebacilli 2 cases (3.6%), mixed form 15 cases(27.2%) were presented. 5) Bacterial culture of bronchoscopic aspiration material; No growth 28 cases (50.9%) were most common finding. In the bacterial growth, alpha hemolytic streptococci 10 cases (18.2%), Neisseria group 7cases(12.7%), Klebsiella 2 cases (3.6%), Pseudomonas 2 cases (3.6%), mixed culture 6 cases (10.9%) were presented, 6) The diagnosis of bronchoscopic appearance, laboratory exam., and pathologic exam. of biopsed specimen were 21 cases (38.1%) primary carcinoma of bronchus, 8 cases (14.5%) pulmonary tuberculosis, 7 cases (12.7%) bronchitis in orders.

• Journal of the Korea Society of Computer and Information
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• v.20 no.2
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• pp.29-45
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• 2015

Systematic theory, concepts, and methodology for the biological evolution have been developed while patterns and principles of the evolution have been actively studied in the past 200 years. Furthermore, they are applied to various fields such as evolutionary economics, evolutionary psychology, evolutionary linguistics, making significant progress in research. In addition, existing studies have applied main biological evolutionary models to artifacts although such methods do not fit to them. These models are also limited to generalize evolutionary patterns of artifacts because they are designed in terms of a subjective point of view of experts who know well about the artifacts. Unlike biological organisms, because artifacts are likely to reflect the imagination of the human will, it is known that the theory of biological evolution cannot be directly applied to artifacts. In this paper, beyond the individual's subjective, the aim of our research is to present evolutionary patterns of a given artifact based on peeping the idea of the public. For this, we propose a text mining approach that presents a systematic framework that can find out the evolutionary patterns of a given artifact and then visualize effectively. In particular, based on our proposal, we focus mainly on a case study of mobile phone that has emerged as an icon of innovation in recent years. We collect and analyze review posts on mobile phone available in the domestic market over the past decade, and discuss the detailed results about evolutionary patterns of the mobile phone. Moreover, this kind of task is a tedious work over a long period of time because a small number of experts carry out an extensive literature survey and summarize a huge number of materials to finally draw a diagram of evolutionary patterns of the mobile phone. However, in this work, to minimize the human efforts, we present a semi-automatic mining algorithm, and through this research we can understand how human creativity and imagination are implemented. In addition, it is a big help to predict the future trend of mobile phone in business and industries.