• Journal of the Korean Vacuum Society
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• v.18 no.4
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• pp.310-317
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• 2009

Vertical wet equipment for the BGA develop process was newly developed substituted for conventional horizontal wet equipment. The benefits of vertical equipment are that the pattern damages generated by the collision between the patterns and transferring rollers can be eliminated because the direct contact between the equipment's transferring units and the soft dry film patterns does not occurs. Taguchi experiment was conducted to optimize the process characteristics for the vertical equipment. The experiment was organized as the smaller the better problem which includes adequate uncontrollable factor and controllable factors. The uncontrollable factors are the 4 sides of two panels which are loaded to the equipment at the same time. By the analysis of the experiment, temperature of the develop chemicals and develop spraying time are analyzed as the main controllable factors. Finally, line pattern's minimum width which is not damaged for the develop process was improved from $13.8{\mu}m$ for the horizontal equipment to $10.4{\mu}m$ for the vertical equipment. And dot pattern's minimum width is improved from $22.1{\mu}m$ to $16.3{\mu}m$.

• Journal of Korea Water Resources Association
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• v.32 no.2
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• pp.99-110
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• 1999

The method of moments, a Lagrangian scheme, considers the zeroth, first, and second moments of the grid cell spatial distributions of the concentration and then advects the concentration by maintaining conservation of the moments. The reasonable inital description of the first and second moments as well as the mean concentration, the zeroth moments, in grid element is important in the method of moments. In this study, the description methods of each initial moment are reviewed, and the method of moments is extended to overcome the restrictions of Courant number. Its performance is compared with those of available Eulerian and Lagrangian schemes. As the results, the method is successfully extended to overcome the stability restriction and is an accurate scheme for the advection simulation of concentration distribution, especially of which the gradient is steep. In addition, the method is very promising scheme in terms of computational efficiency when the mixing is confined in a relatively small region to the entire domain in two-dimensional problem.

• Journal of Korean Ophthalmic Optics Society
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• v.14 no.1
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• pp.87-95
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• 2009

Purpose: The aim of this study is to reveal necessity of orthoptist system in Korea, by comparative analysis between the orthoptist system of developed countries and the present condition in Korean ophthalmic clinics. Methods: Choosing 4 developed countries, we surveyed their education systems, license requirements and process, and service coverage. An inquiry into desirable Korean orthoptist system was added on the basis of the comparative survey. Results: The developed countries have systems in which professional orthoptists, who have got their licenses after official education, do the eye examination under the supervision of ophthalmologists. On the other hand in Korea, a problem is revealed that opticians play a role of eye-examiner in the ophthalmic clinics without any institutional support. Conclusions: The legalistic basis is quite needed in Korea that permit optometry graduates to be eye-examiners in the ophthalmic clinics, by introducing the orthoptist system.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.3
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• pp.89-94
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• 2008

Purpose: To investigate the genetic association of visual acuity(VA) between young children, schoolchildren, juveniles, and their parents. Methods: 208(4 to 18 yrs) subjects who are belongs to young children, schoolchildren and juveniles and 340 their parents were assessed. Corrected and uncorrected visual acuity in each eye were measured using Han's test chart(5m). Results: There was no correlation with father's VA on under 6years but mother's VA tend to effect on male children. In case of elementary school students, their VA shows strong correlations with their parents VA; VA uner 0.7 group shows both parents VA was under 0.7 and VA over 0.7 group tend to shows their parents VA was over 0.7. Moreover, in juvenile, there was strong correlation between mother's VA and male children's VA. Conclusion: Our study showed that the family history, especially mother's visual acuity, had more effect on the problem of their children's visual acuity.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.10
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• pp.985-993
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• 2012

In this paper, a new method is proposed to estimate the sound pressure generated from gasoline direct injection (GDI) engine. There are many noise sources as much as components in GDI engine. Among these components, fuel pump, fuel injector, fuel rail, pressure pump and intake/exhaust manifolds are major components generated from top of the engine. In order to estimate the contribution of these components to engine noise, the total sound pressure at the front of the engine is estimated by using airborne source quantification (ASQ) method. Airborne source quantification method requires the acoustic source volume velocity of each component. The volume velocity has been calculated by using the inverse method. The inverse method requires many tests and has ill-condition problem. This paper suggested a method to obtain volume velocity directly based on the direct measurement of sound intensity and particle velocity. The method is validated by using two known monopole sources installed at the anechoic chamber. Finally the proposed method is applied to the identification and contribution of noise sources caused by the GDI components of the test engine.

• The Journal of Internal Korean Medicine
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• v.30 no.1
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• pp.85-93
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• 2009

Cough is a common clinical problem to which various etiologies are attributable. In Korean medicine there are differentiations in etiology such as food-accumulation and Yin-deficiency. This study was aimed to analyze the relations between the time of cough and Korean syndrome differentiations and to compare the symptoms of Korean syndrome differentiations (food-accumulation and Yin-deficiency). Sixty-two cough patients were analyzed and classified into one of two syndrome differentiations by etiology. We compared the time of coughing and symptomatic characteristics of two: such as symptom differences and change of severity after treatment. Patients with food-accumulation were more prevalent than patients with Yin-deficiency. Among symptoms, anorexia, dyspepsia, nausea and nasal discharge were more prevalent in food-accumulation while pruritus of throat was prevalent in Yin-deficiency. Coughing at night was prevalent in Yin-deficiency and coughing at rising hour was prevalent in food-accumulation.

• Journal of Preventive Medicine and Public Health
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• v.34 no.4
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• pp.347-353
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• 2001

Objectives : To determine the impacts of Diagnosis-Related Groups/Prospective Payment System (DRG/PPS) on the quality of care in cases of Cesarean section and to describe the policy implications for the early stabilization of DRG/PPS in Korea. Methods : Data was collected from the medical records of 380 patients who had undergone Cesarean sections in 40 hospitals participating in the DRG/PPS Demonstration Program since 1999. Cesarean sections were peformed in 122 patients of the FFS(Fee-For-Service) group and 258 patients of the DRG/PPS group. Measurements of quality used included essential tests of pre- and post-operation, and the PPI(Physician Performance Index) score. The PPI was developed by two obstetricians. Results : Univariate analysis demonstrated significant differences in PPI scores according to the payment systems. With respect to the mean of PPI scores, a higher score was found in the DRG/PPS group than in the FFS group. However, the adjusted effect did not show significant differences between the FFS group and the DRG/PPS group. Conclusion : This study suggested that the problem of poor quality may not be related to the implementation of DRG/PPS in Cesarean section. However, this study did not consider the validity and reliability of the process measurement, and it did not exclude the possibility of data emission in medical records.

• Journal of the Korean Society for Library and Information Science
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• v.51 no.1
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• pp.125-146
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• 2017

According to the article of inventory in the act of public records management from $29^{th}$ January on 1999, record repository, special repository and the archives have been doing inventory totally once every two years. As the archives have acquisited incredibly and explosively lots of archives, this has induced a lot of problem in inventory activity due to legacy inventory acts. To solve these problems, the author have revised and legislated on $29^{th}$ Oct. 2016. The purpose of this study is to point out the problems that prior uniformal inventory cycle and to explain in detail that the contents of the newly revised article, and a benefit and expectations of practical inventory activity. The major revision of article is inventory cycle of at least totally once every four years and the act of obligation on a after-process of inventory.

• Education of Primary School Mathematics
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• v.6 no.1
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• pp.11-28
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• 2002

The purposes of this study were to analyze elementary school mathematics textbooks developed in accordance with the 7th national amended curriculum and to find implications for the development of a new revised curriculum to meet the needs of the knowledge-based society. Elementary school mathematics textbooks and accompanying practice books were analyzed. Teacher's manuals were also studied to examine the intentions of the textbook developers. The two major questions were sought. First, to what degree do elementary school mathematics textbooks and practice books match with the intentions of the national curriculum\ulcorner Second, how do elementary school mathematics textbooks and practice books facilitate student's learning for understanding mathematics\ulcorner The findings were as follows. First textbooks, practice books, and teacher's manuals appeared not to reflect the intentions of the 7th amended curriculum to the full extent. Second, characteristics and roles of textbooks, practice books, and teacher's manuals were not clearly defined and therefore, they were not very feasible for teaming for understanding mathematics. The recommendations for a new revised curriculum were suggested. First, regarding the contents presented in the textbooks, the idea of structure of subject matter need to be considered in order to help students to understand connections of concepts and relationships between concepts and functions in mathematics. Second, more ill defined problems should be presented to develop problem solving ability in real life contexts in students. Third, contents for relearning and enrichment need to be reorganized to reflect students' real ability. Fourth, uses of the concrete and the manipulative need to be more realistically suggested. Fifth, more prototypes of performance assessment tasks, scoring rubrics, and portfolios need to be presented in a more teacher-friendly manner. Sixth, characteristics and roles of textbooks and practice books need to be more discernible.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.963-966
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• 2005

Model updating method is known to the area to correct finite element models by the results of the experimental modal analysis. Most common methods in model updating depend on a parametric model of the structure. In this case, the number of parameters is normally smaller than that of modal data obtained from an experiment. In order to overcome this limitation, many researchers are trying to get modal data as many as possible to date. 1 want to name this method multiple modified-system generation method. These Methods consist of direct system modification method and feedback controller method. The direct system modification Is to add a mass or stiffness on the original structure or perturb the boundary conditions. The feedback controller method is to make the closed food system with sensor and actuator so as to get the closed loop modal data. In this paper, we need to focus on the feedback controller method because of its simplicity. Several methods related the feedback controller methods are virtual passive controller (VPC) sensitivity enhancement controller (SEC) and mode decoupling controller (MDC). Among them, we will apply MDC to the model updating problem. MDC has various advantages compared with other controllers, such as VPC and SEC. To begin with, only the target mode can be changed without changing modal property of non-target modes. In addition, it is possible to fix any modes if the number of sensors is equal to that of the system modes. Finally, the required control power to achieve desired change of target mode is always lower than those of other methods such as VPC. However, MDC can make the closed loop system unstable when using incomplete modal data. So we need to take action to avoid undesirable instability from incomplete modal data. In this paper, we address the method to design the unique and robust MDD obtained from incomplete modal data. The associated simulation will be Incorporated to demonstrate the usefulness of this method.