• The KSFM Journal of Fluid Machinery
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• v.12 no.4
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• pp.23-29
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• 2009

For the purpose of high outlet pressure, compactness and low vibration and noise, 2 stage reciprocating air compressors can have various cylinder arrangement: opposed, in-line, and V type. This paper presents an effective method to calculate the inertia forces and to design counter weight. This method is based on the complex representation for the orbital behavior of the compressor shaft. This method helps to find the optimal balancing rate easily to reduce the inertial force or moment. This paper shows that the residual inertia forces of the single throw shafts and the residual inertia moments of the double throw shafts remain to be imbalanced.

• Current Photovoltaic Research
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• v.11 no.1
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• pp.1-7
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• 2023

Flexible dye sensitized photovoltaics (f-DSPVs) based on plastic substrates have attracted significant interest due to their light-weight, flexibility, and compatibility with roll-to-roll processing, as well as their potential application to ubiquitous power sources. However, f-DSPVs exhibit inferior power conversion efficiencies (PCE) compared to conventional DSPVs since the fabrication process must be conducted at a low-temperature (≤ 150℃) to prevent thermal damage of the plastic substrates, which generally results in poor interconnection between the TiO₂ nanoparticles. Numerous novel low-temperature manufacturing approaches for flexible photoanode and counter electrode have been developed. In this review, current progress on low temperature strategies for f-DSPVs technology are discussed.

• The Journal of the Korea Contents Association
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• v.13 no.4
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• pp.35-43
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• 2013

Exercise such as walking is helpful to manage one's own weight and to counter life habit diseases such as obesity. Calorie consumption is usually calculated based on the distance walked. One way to measure the distance is by using steps and stride length. Most pedometers, including some applications in smart devices, are inaccurate, because they use a common value as the average stride length, even though each person has a different stride length. Moreover, the stride length differs depending on the walking pace, which will further increase the error. To address this, in this paper, I classify paces into three categories. Following that, I introduce a customized measurement of stride length, which is calculated based on the stride length corresponding to each pace category after obtaining x, y, z values from a 3-axis accelerometer in the smart device. In addition to this, I developed an application running on the smart device designed for the proposed measurement of stride. I have conducted three experiments for the assessment of the proposed measurement. In conclusion, I confirmed the effectiveness of this system.

• The Korean Journal of Air & Space Law and Policy
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• v.21 no.2
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• pp.123-155
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• 2006

2001. 9. 11 aviation terror showed us that there are lots of problems in aviation security and we need efficient counter-plans. According to this event, many countries are coming up with various countermeasures. After first hijacking in 1950, the aviation terror is occurring with more various methods until these days. And the scale is bigger than former so they're making much bigger damages. Especially, the case of 9.11 terror attracted people's eye of the world because of enormous casualties and damages. It aroused many people's self-awakening therefore as an important factor the security is given much weight in the aviation safety. In order to keep the step like this tendency and the development of aviation security, beginning with America lots of countries of the world are pursuing diverse aviation security's counter-plans of new side. At this point of time, for our development in aviation industry we should make efficient aviation security countermeasures. In this study, We compared our aviation security activities with major countries after 9.11 terror.

• Physical Therapy Rehabilitation Science
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• v.7 no.4
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• pp.179-185
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• 2018

Objective: The purpose of this study was to analyze and compare vertical ground reaction forces during sit to stand (STS) and gait between female elderly and young individuals using the Wii Balance Board (WBB). Design: Cross-sectional study. Methods: Fifty-one female elderly people (age: $75.18{\pm}4.60years$), and 13 young people (age: $29.85{\pm}3.69years$) performed the five times STS test and gait respectively on the WBB. We analyzed time (s), vertical peak (%), integral summation (Int_SUM, %), and counter variables (%) in STS and 1st peak (body weight, BW%), 2nd peak (BW%), peak minimum (BW%), time (second), center of pressure (COP) path length (mm), and Int_SUM (BW%) in gait. The independent t-test was used to assess for differences in STS, gait ability, and general characteristics between the female elderly group and young adults group. With the first and last trials excluded, the mean value was obtained from the middle three of the five trials. Results: During STS, Int_SUM and time of young adults were significantly less than of the female elderly subjects. There were no significant differences in peak and counter variables. In gait, all variables (1st peak, 2nd peak, min, time, COP_path, and Int_SUM) showed significant differences between groups (p<0.05). This study demonstrated that the validity of vertical ground reaction forces occurring during STS and gait was significant in female elderly and young adults. Conclusions: Based on the measurement of vertical ground reaction forces in STS and gait using the WBB, it is possible to clinically improve the quality of geriatric physical therapy. Further studies are necessary to examine concurrent validity of elderly patients who have undergone total hip or knee replacement.

• Journal of the Korea Society of Computer and Information
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• v.28 no.8
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• pp.77-86
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• 2023

The background of this study lies in the increasing economic value of Korean fonts and the necessity for font development focused on small character design suitable for the mobile environment. The objective of this study is to analyze and propose strategies to improve readability on mobile screens. The research was conducted by applying eight attributes that could enhance readability according to Tim Ahrens to the design process of a Korean mobile font, adjusting Google's Noto Sans Korean for print/publishing and for small sizes. The results of the study indicate that 1. type width should be increased, 2. open counter (interior space) should be increased, 3. closed counter should be decreased, 4. font weight should be increased, 5. stroke contrast should be decreased, 6. spacing between characters should be increased. Therefore, distinct font families should be provided, differentiating between print/publishing and mobile use, as well as varying font weights and sizes, applying readability and legibility enhancement techniques for Korean fonts.

• Particle and aerosol research
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• v.16 no.2
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• pp.49-59
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• 2020

Various devices have been developed to the measurement of particulate matter pollutants, and Optical Particle Counter (OPC) that can be easily and quickly measured is widely used lately. The measured value by OPC is converted to weight concentration using the correction factor (CF). The calculation of CF is very important to improve the reliability and accuracy of OPC. In this study, the CF calculation study of light scattering laser photometer (model 8533, TSI) was carried out to measure in the atmospheric environment using 2 gravimetric devices and 3 light scattering laser photometer devices. Regression analysis and Tukey tests were used to significance the test of measurement devices. Measurements were carried out twice. There was a comparative analysis of measurement data between light scattering laser photometer and gravimetric devices in 1st measurement, and then the Evaluation of PM2.5 concentration corrected by CF performed in 2nd measurement. As a result of the significance analysis between light scattering laser photometer and gravimetric devices, the correlation between the same method was high, but the correlation between different methods was low. CF was calculated as 0.4258 based on the measurement results, and it is a similar level to previous studies at home and abroad. It is expected that these results can be used as basic data in the future study for air quality measurement research using light scattering laser photometer. Also, in order to improve the accuracy of the measurement techniques and the development of technology in the atmospheric environment, CF calculation research should be conducted continuously.

• Journal of Radiation Protection and Research
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• v.31 no.3
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• pp.155-164
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• 2006

It is judged that there could be certainty in every process of analyzing environmental samples using Liquid Scintillation Counter. Therefore, this study focuses on quantitative evaluation on uncertainty in an effort to analyze comparatively accurately environmental samples. For this, after parameters which can have an effect on uncertainty was derived, the evaluation on each parameter was tamed out. The results of analysis of each parameter showed that the effect according to the weight difference of Teflon vial did not appear, and that standard deviations of SQP(E) averages reached saturation point at $75{\sim}90$ sec at the result of making increases step by step the irradiation time of External standard, and that values measured by repeat method produces good results compared with replicate. Also, conclusion was derived that analysis on sample after it is left in cold and dark room at least above 1,000 minutes have to be carried out, and the result of carrying out verification on results measured as well as equipment itself using radioactivity-error-analysis and chi-square test, resonable result was derived.

• Journal of Korean Academy of Nursing
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• v.1 no.1
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• pp.77-84
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• 1970

A survey was conducted on 2,321 Chung Rhang Middle School boys to check out their physical growth, development and the number of parasite carriers during the period from June 16. to June 23. 1970 As the results of this study, the following conclusions were revealed. A) Physical Growth and Development State. 1. Direct curve in physical growth and development was observed during the period from 13 to 16 years of age. 2. The age and quantity of maximum growth and development. Height; 13~14 years of age 6.1cm Body weight; 14~15 years of age 5.1kg Chest circumference; 13~14 years of age 9.9cm Sitting height; 14~15 years of age 3.4cm 3. Comparison with Japanese students Most Korean students are shorter than Japanese students, though the standard of height became higher than before. The standard of body weight is visibly lower than Japanese students. The standard of chest circumference of the students of age 14 is higher than counter part of Japanese students and the all boys are lower than Japanese students except at the age of 14. The standard of the sitting heights of the Korean students are growing steadily, but every students are shorter than Japanese students. 4. The greatest differences in physical growth and development were shown in 13~14 years of age. 5. The students of 13~15 years of age developed their bodies most highly according to index of Rohrer. 6. Body weight and chest circumference have not grown enough compared with height. The development of sitting height was made highly and the development is steadily growing as they grow old. B. The Number of Parasite Carriers The number of parasite carriers was shown 79.4 per cent among all the student checked out. The number of trichuris was shown 79.7 per cent. The number of parasite carriers was shown higher per cent as the grow old.

• The Korean Journal of Pharmacology
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• v.32 no.3
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• pp.433-444
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• 1996

We describe a novel approach to evaluate quantitatively the amounts of denatured proteins in cells upon heat exposure. A thiol compound, diamide [azodicarboxylic acid bis (dimethylamide)] causes protein cross-linking with exposed sulfyhydryl residues of denatured proteins. Since denatured proteins expose normally well-hidden sulfhydryl groups, these will be preferentially cross-linked by diamide. Thus diamide acts to 'trap' denatured proteins. We observed that protein aggregates (high molecular weight protein aggregates, HMA) appeared on SDS-polyacrylamide gels run under non-reducing conditions and that the amount of HMA can be quantified by scanning the gels using a gas flow counter. Heating cells followed by a fixed dose of diamide exposure resulted in HMA increases in a heat-dose dependent manner, demonstrating that the quantitation of HMA could serve as a measure of heat-denatured proteins. We compared thermotolerant and nontolerant cells and found decreased HMA in tolerant cells upon heat treatment. As an attempt to examine the kinetics of protein renaturation (or 'repair'), we measured the amounts of aggregates formed by the addition of diamide at various times after heat shock. Such experiments demonstrate an equally rapid disappearance of HMA in previously unheated and in thermotolerant cells. Levels of HMA in tolerant cells increased significantly after electroporation of HSP70 specific mAbs, suggesting an involvement of HSP70 in reducing HMA levels in thermotolerant cells upon heat exposure. Immunoprecipitation studies using anti-HSP70 antibody indicated an association of HSP70 with heat-denatured proteins. Our results suggest that heat induces protein denaturation, and that elevated level of HSP70 present in thermotolerant cells protects them by reducing the level of protein denaturation rather than by facilitating the 'repair' (or degradation) process.