• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.06a
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• pp.16-23
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• 2000

The increasing functional needs of top-quality printing papers and packaging paperboards, and especially the rapid developments in electronic printing processes and various computer printers during past few years, set new targets and requirements for modern paper quality. Most of these paper grades of today have relatively high filler content, are moderately or heavily calendered , and have many coating layers for the best appearance and performance. In practice, this means that many of the traditional quality assurance methods, mostly designed to measure papers made of pure. native pulp only, can not reliably (or at all) be used to analyze or rank the quality of modern papers. Hence, introduction of new measurement techniques is necessary to assure and further develop the paper quality today and in the future. Paper formation , i.e. small scale (millimeter scale) variation of basis weight, is the most important quality parameter of paper-making due to its influence on practically all the other quality properties of paper. The ideal paper would be completely uniform so that the basis weight of each small point (area) measured would be the same. In practice, of course, this is not possible because there always exists relatively large local variations in paper. However, these small scale basis weight variations are the major reason for many other quality problems, including calender blacking uneven coating result, uneven printing result, etc. The traditionally used visual inspection or optical measurement of the paper does not give us a reliable understanding of the material variations in the paper because in modern paper making process the optical behavior of paper is strongly affected by using e.g. fillers, dye or coating colors. Futhermore, the opacity (optical density) of the paper is changed at different process stages like wet pressing and calendering. The greatest advantage of using beta transmission method to measure paper formation is that it can be very reliably calibrated to measure true basis weight variation of all kinds of paper and board, independently on sample basis weight or paper grade. This gives us the possibility to measure, compare and judge papers made of different raw materials, different color, or even to measure heavily calendered, coated or printed papers. Scientific research of paper physics has shown that the orientation of the top layer (paper surface) fibers of the sheet paly the key role in paper curling and cockling , causing the typical practical problems (paper jam) with modern fax and copy machines, electronic printing , etc. On the other hand, the fiber orientation at the surface and middle layer of the sheet controls the bending stiffness of paperboard . Therefore, a reliable measurement of paper surface fiber orientation gives us a magnificent tool to investigate and predict paper curling and coclking tendency, and provides the necessary information to finetune, the manufacturing process for optimum quality. many papers, especially heavily calendered and coated grades, do resist liquid and gas penetration very much, bing beyond the measurement range of the traditional instruments or resulting invonveniently long measuring time per sample . The increased surface hardness and use of filler minerals and mechanical pulp make a reliable, nonleaking sample contact to the measurement head a challenge of its own. Paper surface coating causes, as expected, a layer which has completely different permeability characteristics compared to the other layer of the sheet. The latest developments in sensor technologies have made it possible to reliably measure gas flow in well controlled conditions, allowing us to investigate the gas penetration of open structures, such as cigarette paper, tissue or sack paper, and in the low permeability range analyze even fully greaseproof papers, silicon papers, heavily coated papers and boards or even detect defects in barrier coatings ! Even nitrogen or helium may be used as the gas, giving us completely new possibilities to rank the products or to find correlation to critical process or converting parameters. All the modern paper machines include many on-line measuring instruments which are used to give the necessary information for automatic process control systems. hence, the reliability of this information obtained from different sensors is vital for good optimizing and process stability. If any of these on-line sensors do not operate perfectly ass planned (having even small measurement error or malfunction ), the process control will set the machine to operate away from the optimum , resulting loss of profit or eventual problems in quality or runnability. To assure optimum operation of the paper machines, a novel quality assurance policy for the on-line measurements has been developed, including control procedures utilizing traceable, accredited standards for the best reliability and performance.

• Clinical and Experimental Reproductive Medicine
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• v.28 no.4
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• pp.287-293
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• 2001

Objective : To investigate the efficacy of high infusion frequency of liquid nitrogen on pregnancy in human embryo after freezing and thawing. Materials and Methods: 150 infertile patients underwent 162 consecutive thawing-ET cycles. In the high infusion frequency group (Group A), 47 patients (50 cycles) underwent cryopreservation with high infusion frequency of liquid nitrogen. In the low infusion frequency group (Group B), 103 patients (112 cycles) underwent cryopreservation with low infusion frequency of liquid nitrogen. We analyzed the clinical characteristics, fertilization rates, development of embryo, good quality embryo ratio, implantation rates, and pregnancy rates between these two groups. Results: There was no difference between the groups with regard to clinical characteristics (mean age, infertility duration, infertility factors, hormone profile), mean number of oocyte retrieval, fertilization rates, and mean embryo number of transfers. The survival rates in group A was 64.9% (228 of 350 embryos), and among the 228 embryos 190 embryos (83.3%) which progressed to the two- to eight-cell stage. After thawing, the embryo numbers were 65 (34.2%), 29 (15.3%), 35 (18.4%), and 37 (19.5%) of grades 1, 2, 3, and above 4, respectively. The survival rates in group B was 63.8% (482 of 755 embryos), and among the 482 embryos 465 embryos (96.5%) which progressed to the two- to eight-cell stage. After thawing, the embryo numbers were 106 (22.8%), 94 (20.2%), 89 (19.1%), and 112 (24.1%) of grades 1, 2, 3, and above 4, respectively. There was no difference in embryo quality change after the freezing-thawing procedure between the groups. Implantation rates (31.1% vs. 34.3%) were not significant. However hCG positive rates in group A (40%) were higher than group B, but not statistically significant. Clinical pregnancy rate (26% vs. 25.9%), on going pregnancy rates (>20 weeks) were not significant (26% vs. 25%). Conclusion: We compared embryo quality change, survival rates, and pregnancy rates between high infusion frequency group and low infusion frequency group and the results were similar between the two groups. Therefore, high infusion frequency of liquid nitrogen for cryopreservation is a worthy method to preserve in human embryos.

• Journal of Korean Clinical Health Science
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• v.6 no.1
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• pp.1065-1073
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• 2018

Purpose. In this study, we aim to clarify the correlation between happiness, appearance, and happiness index among many happiness factors based on the influence of quality of life on the quality of life and the affect of appearance on the happiness index. Methods. We conducted a self - filling questionnaire survey for college students in Busan from March 30 to May 10, 2017, and analyzed 392 copies of the 412 questionnaires, excluding 20 inappropriate copies. In the questionnaire, categorical data were analyzed by frequency and percentage (%) using the SPSS program (ver. 23.0, Chicago, Illinois, USA) by examining 11 items of general characteristics, successive data are presented as mean standard deviation. Results. The higher the grades, the better the dating. Women(3.32) are more likely than men(2.74) at the appearance interest(p>0.001) and the higher the grades, the better. If it's dating someone else, higher than not to do at the appearance interest and all of the questions showed higher interest in appearance. Also there was a high percentage of thought'My life is ideal in all aspects'If it's dating someone else, higher than not to do (p=0.007) Conclusion. At present, There is a high interest in the appearance of dating. In addition, the happiness index according to the current resentment status was higher in both the single item happiness index and the 5 item happiness index, and was significant in the item "My life is ideal in all aspects". Therefore, it is related to the happiness index as well as the appearance interest. Finally, whether or not dating and appearance interest play a role in raising the happiness of the individual.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.3
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• pp.357-366
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• 1997

Rice quality is considered to have two general meanings; 1) milling, cooking, and processing quality, which refer to suitability of the grain for a particular end-use; and 2) physical quality, which means cleanliness, soundness, and freedom from foreign materials. Grain type is associated with specific milling, cooking, and processing characteristics. Thus, this experiment was conducted to classify the grain type categories and marketing grades for Korean leading rice varieties. Length: width ratio of brown rice kernel ranged from 1.57 to 2.25 and most of varieties belonged to short grain except Tongil type rice varieties. Mean of length: width ratio of brown rice kernel was 1.77 and coefficient of variance was 4.79％ in short grain type varieties. Grain shape could be further classified into 5 types by length:width ratio of brown rice kernel; 1 type(less than 1.75), 2 type(1.76∼1.80), 3 type(1.81∼1.90), 4 type(1.91∼2.00), and 5 type (greater than 2.00). For 1 and 2 type of varieties, woven wire sieve having 1.7mm openings showed better whole-kernel yields for special marketing grade, and sieve having 2.0mm openings for 3 and 4 type of varieties. Grain type which classified into 5 categories was not associated with physicochemical and cooking characteristics of rice grain, but sensory evaluation of cooked rice showed better score for 1 type varieties in terms of appearance, gloss, flavor, texture, stickiness, and taste.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.13-22
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• 2007

This study was carried out to scrutinize possibility of manufacturing pitch pine (Pinus rigida) glued laminated timber in order to add values of pitch pine trees. Also, it was investigated to improve bending performance of pitch pine glulam. Pitch pine was imported as one of major plantation species in Korean peninsula. Machine stress rated grades of pitch pine lumber mostly ranged between E7 and E9. which grades were more or less inferior to producing high quality glulam. However, the adhesive properties between pitch pine and pitch pine, and between pitch pine and Japanese larch (Larix kaempferi Carr.), such as shear bond strength, wood failure rate and de-lamination rate of bonded layer submerged in cold and boiling water, were higher than Korean Standard criteria. These properties are essential for manufacturing glulam with single species or multiple species. The modulus of rupture (MOR) of pitch pine glulam exceeded the criterion of Korean Standard for glulam strength grade but modulus of elasticity (MOE) was lower than the criterion. On the other hand, the bending performances (MOR and MOE) were improved 20 percent by mixing with Japanese larch laminar. It is effective to arrange higher quality Japanese larch laminar at the outer layer of glulam for improving bending performances. In conclusion, it is possible to use low quality pitch pine as laminar of structural glulam for adding values of pitch pine.

• Korean Journal of Radiology
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• v.19 no.6
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• pp.1031-1041
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• 2018

Objective: To compare image quality and radiation dose of high-pitch dual-source spiral cardiothoracic computed tomography (CT) between non-electrocardiography (ECG)-synchronized and prospectively ECG-triggered data acquisitions in young children with congenital heart disease. Materials and Methods: Eighty-six children (${\leq}3$ years) with congenital heart disease who underwent high-pitch dual-source spiral cardiothoracic CT were included in this retrospective study. They were divided into two groups (n = 43 for each; group 1 with non-ECG-synchronization and group 2 with prospective ECG triggering). Patient-related parameters, radiation dose, and image quality were compared between the two groups. Results: There were no significant differences in patient-related parameters including age, cross-sectional area, body density, and water-equivalent area between the two groups (p > 0.05). Regarding radiation dose parameters, only volume CT dose index values were significantly different between group 1 ($1.13{\pm}0.09mGy$) and group 2 ($1.07{\pm}0.12mGy$, p < 0.02). Among image quality parameters, significantly higher image noise ($3.8{\pm}0.7$ Hounsfield units [HU] vs. $3.3{\pm}0.6HU$, p < 0.001), significantly lower signal-to-noise ratio ($105.0{\pm}28.9$ vs. $134.1{\pm}44.4$, p = 0.001) and contrast-to-noise ratio ($84.5{\pm}27.2$ vs. $110.1{\pm}43.2$, p = 0.002), and significantly less diaphragm motion artifacts ($3.8{\pm}0.5$ vs. $3.7{\pm}0.4$, p < 0.04) were found in group 1 compared with group 2. Image quality grades of cardiac structures, coronary arteries, ascending aorta, pulmonary trunk, lung markings, and chest wall showed no significant difference between groups (p > 0.05). Conclusion: In high-pitch dual-source spiral pediatric cardiothoracic CT, additional ECG triggering does not substantially reduce motion artifacts in young children with congenital heart disease.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.4
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• pp.246-252
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• 1992

In order to reduce the problems from overlapping between rye harvest and maize seeding dates, and also to improve the growth, productivity and nutritive value of rye (Secale cereale L.), an experiment was carried out to determine the variety effect of rye on the forage production system, and seeding date effect on the yield and quality of rye. The experiment was conducted in the forage testing field of S.N.U., Suweon, from September 1988 to May 1989. The dry matter and in vitro digestible dry matter yields of rye harvested 14 April were 5.2 t and 4.6 t/ha with an early maturing rye variety, Winter more, but 3.1 t and 2.8 t/ha were obtained with a late maturing rye variety, Kodiak. When seeding date was delayed, a significant decrease in dry matter yield was observed. ADF and NDF contents, and IVDMD of an early maturing rye, Winter more, harvested 14 April were 25.6, 44.8 and 81.9 %, but those of a late maturing rye, Kodiak, were 21.1, 39.5 and 88.9 %, respectively. ADF and NDF contents of rye were increased as the seeding date was delayed, but ail forage ryes from different seeding dates as well as varieties were recorded as the 1st grade proposed by market hay grades. The dry matter and in vitro digestible dry matter yields of rye harvested at 80 %heading stage were significantly decreased as delayed seeding date, but no significant differences were found between early and late maturing varieties. No differences in ADF and NDF contents, and IVDMD of the rye harvested at 80% heading stage were found among the treatments, but all forage ryes were evaluated as the 4 th grade proposed by market hay grades.

• Journal of Embryo Transfer
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• v.15 no.3
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• pp.287-293
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• 2000

This study was undertaken to access the effects of collection method, room temperature at oocyte recovery and culture media on the oocyte quality, fertilization and cleavage rates of in vitro matured and fertilized oocytes of Korean native goats. Ovaries obtained from a slaughterhouse were transported to the laboratory and were divided into 2 groups. One group of ovaries was maintained at 30 to 35$^{\circ}C$ of the room temperature and another group was remained at 20 to $25^{\circ}C$ during oocyte recovery. The oocytes were recovered by follicle aspiration, slicing and aspiration+slicing methods from 3 groups of follicles according to size; <2 mm, 2 to 6 mm and >6 mm. The matured oocytes were inseminated with buck epididymal spermatozoa at a concentration of 3~3.5$\times$10$^{6}$ m1 and fertilization was identified when 2 pronuclei were present in the cytoplasm. Although the recovery rate per ovary obtained by the combination of follicle aspiration + slicing(19.6$\pm$2.2) method was higher than aspiration(11.7$\pm$1.1) and slicing(14.8$\pm$1.8) collection, optimal recovery according to oocyte grades resulted form ovarian slicing compared to aspiration or combined methods(P<0.05). However, no significant differences were found in the mean number(2.5$\pm$1.8; 3.3$\pm$3.3; 2.9$\pm$2.4) and the proportion of favorable oocytes(Grades I, II and III) recovered(31.6%, 36.0%, 36.4%,) according to follicle size(<2 mm; 2 to 6 mm; >6 mm). Fertilization rate was 60.0%, 67.7%, 70.6% and 56.4% and the proportion of embryos/zygotes was 11.1%, 7.1%, 5.0% and 2.8% in 20~$25^{\circ}C$/BO, 30~35$^{\circ}C$/BO, 20~$25^{\circ}C$/TALP and 30~35$^{\circ}C$ /groups, respectively.

• Health Policy and Management
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• v.20 no.1
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• pp.19-36
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• 2010

Fee for long-term care insurance in Korea are determined in proportion to resources utilized according to severity rather than based on categorization of beneficiaries in consideration of the characteristics of resource utilization. This adoption is based on the assumption that as beneficiaries of long-term care insurance, characteristically, demands social services rather than needs medical treatments, the characteristics of beneficiaries and the quality of utilized resources are comparatively homogenous. Therefore, the proposition is that the size of resource consumed by beneficiaries in the same grade is identical. However, even in the same grade, the level of utilized resources is different depending on the characteristic of beneficiaries. In this regard, this study is to examine whether there are differences in the volumes of utilized resources depending on the characteristics of beneficiaries even in the same grade. We analyzed time study data for 2003, 2005, 2006 which conducted by the Korea Institute for Health and Social Affairs. To look at differences in the volumes of utilized resources, we identified characteristics of beneficiaries that influence utilized resource volumes and categorized services provided by facilities into the rehabilitation treatment category, the problematic behavior category, and the physical malfunction category. Then, we examined each service in consideration of service difficulty levels and wage weights. The result of examination showed that differences in utilized resource volumes exist in all three grades depending on the characteristics of beneficiaries. Especially, in the first grade with a high level of seriousness, utilized resource volumes were different for those three service categories and the problematic behaviour category considered dementia was found to consume the largest volume of resources. Moreover, there was the inversion phenomenon of utilized resources volumes between the grades. This result indicates that utilized resource volumes are different even in the same grade depending on the characteristics of beneficiaries and it is required to consider case-mix for reflection of the volumes of utilized resources depending on the characteristics of beneficiaries.

• Journal of Korea Multimedia Society
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• v.6 no.5
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• pp.816-823
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• 2003

In this paper, we propose a blind audio watermarking using the tonal characteristic. First, we explain the perceptional effect of tonal on the existed researches and shout the experimental result that tonal characteristic is more stable than other characteristics used in previous watermarking studies against several signal processing. On the base of the result, we propose the blind audio watermarking using the relation among the signals on the frequency domain which compose a tonal masker. To evaluate the sound quality of our watermarked audios, we used the SDG(Subjective Diff-Grades) and got the average SDG 0.27. This result says the watermarking using the perceptional effect of tonal is available from the viewpoint of non-perception. And we detected the watermark hits from the watermarked audios which were changed by several signal processing and the detection ratios with exception of the time shift processing were over 98%. About the time shift processing, we applied the new method that searched the most proper position on the time domain and then detected the watermark bits by the ratio of 90%.