• Structural Engineering and Mechanics
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• v.87 no.3
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• pp.283-296
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• 2023

Free-vibration and buckling analyses of plate problems are investigated with the aid of the strain gradient notation finite element method (SGN-FEM). As SGN-FEM employs physically interpretable polynomials in developing finite elements, parasitic shear sources, which are the cause of shear locking, can be precisely identified and subsequently eliminated. This allows two mutually complementary objectives to be defined in this work, namely, evaluate the efficiency of free-vibration and buckling results provided by corrected models, and study the severity of parasitic shear effects on plate models performance. Parasitic shear are flexural terms erroneously present in shear strain polynomials. It is reviewed here that six parasitic shear terms arise during the formulation of the four-node Mindlin plate element. Two parasitic shear terms have been identified in the in-plane shear strain polynomial while other two have been identified in each of the transverse shear strain polynomials. The element is corrected a-priori, i.e., during development, by simply removing the spurious terms from the shear strain polynomials. The computational implementation of the element in its two versions, namely, containing the parasitic shear terms (PS) and corrected for parasitic shear (SG), allows for assessments of the accuracy of results and of the deleterious effects of parasitic shear in free vibration and buckling analyses. This assessment of the parasitic shear effects is a novelty of this work. Validation of the SG model is done comparing its results with analytical results and results provided by other numerical procedures. Analyses are performed for square plates with different thickness-to-length ratios and boundary conditions. Results for thin plates provided by the PS model do not converge to the correct solutions, which indicates that parasitic shear must be eliminated. That is, analysts should not rely on refinement alone. For thick plates, PS model results can be considered acceptable as deleterious effects are really critical in thin plates. On the other hand, results provided by the SG model converge well for both thin and thick plates. The effectiveness of the SG model is established via high-accuracy results obtained in several examples. It is concluded that corrected SGN-FEM models are efficient alternatives for free-vibration and buckling analysis of Mindlin plate problems, and that precise elimination of parasitic shear is a requirement for sound analyses.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.891-899
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• 2015

The lily symptomless virus (LSV) is the most common virus in Korean native lilies and causes various types of damage to overall plant growth. This study was carried out to investigate the elimination rate of the LSV by the in vitro scale culture (scaling) method in Korean native lilies and to test reinfection rates of the LSV under several field culture conditions of bulb production. Four Korean native lilies (Lilium dauricum, L. distichum, L. lancifolium, and L. maximowitzii) were used and their scales were cultured in vitro for micro-scale formation. The micro-scales were subcultured repeatedly using MS culture medium supplemented with 30 or $90g{\cdot}L^{-1}$ sucrose. The culture conditions were $24{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD with 16 hour daylength using fluorescent lamps and maintained at $22{\pm}2^{\circ}C$. The virus-free bulblets were grown for one to three years in the greenhouse and transplanted to the field in October or March. Virus infection rates were investigated by direct tissue blotting immunobinding assays and measurement of chlorophyll and protein contents. Virus-free plants could be obtained from the 5th subculture of micro-scales in L. lancifolium and L. maximowitzii or from primary culture in L. dauricum and L. distichum. LSV-free plants were reinfected during bulb production in the field. Reinfection rates were higher at older bulb ages and under higher planting density. The plants planted in October and at inland Gyeongsan had higher infection rates than those planted in March and at coastal area Pohang. The reinfection rate of L. maximowitzii was higher than those of L. dauricum and L. lancifolium. The LSV-infected plants had lower chlorophyll contents and unchanged protein contents compared to virus-free plants.

• Journal of Korean Academy of Nursing
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• v.3 no.3
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• pp.97-110
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• 1973

The goal of modern nursing is to provide comprehensive nursing care to patients. If comprehensive nursing care to children (within the hospital setting) is to be provided, consideration of the stage of growth and development of the child is especially important. From clinical observation, it appeared that nurses often disregarded individual requirements of children in giving nursing care. Therefore, the purpose of this study is to show that comprehensive nursing care which is based on an understanding of the growth and development of the child contributes to both the child and the mother's adaptability to the child's hospitalization. Method: Sixty children, three to three year of age, hospitalized at the Yonsei University Pediatric Ward ware studied. From April 1, 1973 to May 5, 1973, children admitted to the hospital were assigned to either an experimental or a compare groups. There were 30 children in each group. The sex and age of the children in each group was similar. In both groups were more male than female children. In the experimental group, each mother stayed with hot child continuously during his hospitalization. In the compare groups, the mother or some other member of the family stayed with the child. Each day on the child's admission the investigator visited the ward from 1-2 P.M. to 9-10 P.M., in order to provide comprehensive care for the experimental -group. The assistance given the nurses by the investigator was in the form of conferences regarding care and in giving direct care to the child and his mother. The compare group of children received nursing care as usually provided by the hospital. The instruments used to obtain the data for analysis were as follows: 1. The fear and anxiety reaction of the child was recorded by observation of the investigator for four areas: 1) separation from parent and relatives 2) reaction to Doctor and Nurse with white gowns 3) reaction to nursing care 4) reaction to injection and tests, etc. 2. Regression in area of eating, sleeping, and elimination were recorded by the investigator by questioning the mother and by observation. 3. Adaptability to the hospitalization was recorded by direct questioning of the children for areas of emotional and social adjustment. For children older than 3 years of age or children not seriously ill, using the simple I. Q. test this was possible for only 35 of the total 60 children. Result: 1. 55 percents of the total 60 children had been prepared by their parents for hospitalization. The children who had received prior preparation accepted hospitalization more readily than those who had received no preparation. (χ²=4.6 Ρ<0.05) 2. On admission 31.7 percent of the children expressed verbal fear of their discase or treatment. 25 percent felt that the disease was due to their mistake. 3. There was a significant difference in the reaction of the child to separation from the parent or relatives between the two groups. The experimental groups showed less anxiety due to separation than the compare group. (χ²=4.34 Ρ<0.05) In both groups there was less anxiety due to separation among school age (6-12 years) children than among preschool age (3-5 years) children. (χ²=9.22 Ρ<0.05) 4. More than half of the children in both groups reacted with fear and avoidance to doctor and/or nurses wearing white gowns. (χ²=0.06 Ρ<0.05) 5. The experimental group reacted more favorably to nursing in general than the compare group. (χ²=4.8 Ρ<0.05) 6. There was no difference in the fear and refused reaction to special tests and/or such as X-rays and injections, etc. between the groups. (χ²=3.77 Ρ<0.05) 7. More children in the compare group showed regressive tendencies in eating, sleeping, and elimination habits than in experimental groups. (χ²=2.3 Ρ<0.05 χ²=3.88 Ρ<0.05 χ²=4.9 Ρ<0.05) 8. There was a significant difference in the adaptability to hospitalization between the two groups. The experimental groups adapted more readily. (χ²=2.02 Ρ<0.05) 9. For children who had higher I.Q. s the adaptability to hospitalization was better regardless of the group. (χ²=5.03 Ρ<0.05) However, because of the small number of cases (60), this finding cannot be extrapolated without further verification. The date demonstrates that there was a greater adaptability to hospitalization by the child when comprehensive nursing care was given. By planning care and applying knowledge of growth and development to meet, nurses are in a position to prevent some of the psychological trauma associated with hospitalization.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.29 no.1
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• pp.14-27
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• 2024

Unlike the shelf sand ridges moribund in motion, nearshore sand ridges are highly mobile, sensitive to changes in ocean environments, thereby becoming of particular interest with respect to morphological changes. About 5 km off the Daesan port, the Jangan Sand Ridge has been undergoing severe subsea morphological change over the past two decades. Understanding the nature of sand ridges is critical to elucidate the causes of morphological changes. In this context, this study aims at understanding the characteristics and distribution patterns of surface sediments of the ridge and its vicinity. For this purpose, 227 sediment samples were acquired using a grab-sampler, the grain sizes being analysed by the sieve-pipette method. In addition, comparison of grain sizes in sediments between 1997 and 2021 was made in order to investigate the 25-years change in sediment composition. Surface sediments along the ridge axis are fine to medium sands with 2-3 phi in mean grain size, whereas, in the trough of ridge, the sediments are composed of gravels and muddy sandy gravels with mean sizes of -2 to -6 phi. Sediments in the crest of the ridge are well-sorted with normal distribution, on the other hand, the basal sediments are poorly-sorted and positively skewed. Along the ridge crest, the sediments are negatively skewed. From 1997 to 2021, the ridge sediments became largely coarser about 0.5 phi. Such coarsening trend in mean grain size can be explained either by elimination of fine sediments during high waves in winter or elimination of fines suspended during sand mining activities in the past. Spatial distribution pattern of surface sediments shows that ca. 30 m thick of the sand ridge itself overlies the thin relict gravels. The strong asymmetry of sand ridge, the exposure of ridge base, and reworked gravel lags suggest that Jangan sand ridge is probably sediment-deficit and hence erosive in nature at present.

• Journal of Intelligence and Information Systems
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• v.26 no.4
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• pp.173-198
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• 2020

For a long time, many studies have been conducted on predicting the success of campaigns for customers in academia, and prediction models applying various techniques are still being studied. Recently, as campaign channels have been expanded in various ways due to the rapid revitalization of online, various types of campaigns are being carried out by companies at a level that cannot be compared to the past. However, customers tend to perceive it as spam as the fatigue of campaigns due to duplicate exposure increases. Also, from a corporate standpoint, there is a problem that the effectiveness of the campaign itself is decreasing, such as increasing the cost of investing in the campaign, which leads to the low actual campaign success rate. Accordingly, various studies are ongoing to improve the effectiveness of the campaign in practice. This campaign system has the ultimate purpose to increase the success rate of various campaigns by collecting and analyzing various data related to customers and using them for campaigns. In particular, recent attempts to make various predictions related to the response of campaigns using machine learning have been made. It is very important to select appropriate features due to the various features of campaign data. If all of the input data are used in the process of classifying a large amount of data, it takes a lot of learning time as the classification class expands, so the minimum input data set must be extracted and used from the entire data. In addition, when a trained model is generated by using too many features, prediction accuracy may be degraded due to overfitting or correlation between features. Therefore, in order to improve accuracy, a feature selection technique that removes features close to noise should be applied, and feature selection is a necessary process in order to analyze a high-dimensional data set. Among the greedy algorithms, SFS (Sequential Forward Selection), SBS (Sequential Backward Selection), SFFS (Sequential Floating Forward Selection), etc. are widely used as traditional feature selection techniques. It is also true that if there are many risks and many features, there is a limitation in that the performance for classification prediction is poor and it takes a lot of learning time. Therefore, in this study, we propose an improved feature selection algorithm to enhance the effectiveness of the existing campaign. The purpose of this study is to improve the existing SFFS sequential method in the process of searching for feature subsets that are the basis for improving machine learning model performance using statistical characteristics of the data to be processed in the campaign system. Through this, features that have a lot of influence on performance are first derived, features that have a negative effect are removed, and then the sequential method is applied to increase the efficiency for search performance and to apply an improved algorithm to enable generalized prediction. Through this, it was confirmed that the proposed model showed better search and prediction performance than the traditional greed algorithm. Compared with the original data set, greed algorithm, genetic algorithm (GA), and recursive feature elimination (RFE), the campaign success prediction was higher. In addition, when performing campaign success prediction, the improved feature selection algorithm was found to be helpful in analyzing and interpreting the prediction results by providing the importance of the derived features. This is important features such as age, customer rating, and sales, which were previously known statistically. Unlike the previous campaign planners, features such as the combined product name, average 3-month data consumption rate, and the last 3-month wireless data usage were unexpectedly selected as important features for the campaign response, which they rarely used to select campaign targets. It was confirmed that base attributes can also be very important features depending on the type of campaign. Through this, it is possible to analyze and understand the important characteristics of each campaign type.

• Journal of the Korean Vacuum Society
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• v.18 no.2
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• pp.97-101
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• 2009

In the modem semiconductor industry, the progress that consumes the most capital and labor is cleansing process. Cleansing process is to remove impurities that can affect the operation of the device and deteriorate its function. Especially, Photoresist (PR) progress that etches the device always requires cleansing at the end of the progress. Also, HDI-PR (High-Dose Ion-implanted Photoresist) created from PR progress is difficult to remove. Thus, in modem IC cleansing, many steps of cleansing are used, including dry and wet cleansing. In this paper, we suggested to combine existing dry-cleansing and wet-cleansing, each represented by plasma cleansing and stripper solution, as Plasma Liquid-Vapor Activation (PLVA). This PLVA method enhances the effect of existing cleansing solution, and decreases the amount of solution and time required to strip. We stripped HDI-PR by activated solution and measured surface hardness and Young's modulus by Nano-indenter. Nano-indenter is the equipment that determines the hardness and the modulus of elasticity by indenting nano-sized tip with specific shape into the surface and measuring weight and z-axis displacement. We measured the change of surface hardness and Young's modulus before and after the cleansing. As a result, we found out that the surface hardness of the sample sharply decreased after the cleansing by plasma-activated PR stripper solution. It can be considered that if physical surface-cleansing process is inserted after this, more effective elimination of HDI-PR is possible.

• Management & Information Systems Review
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• v.30 no.2
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• pp.211-235
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• 2011

We examined the relationship between innovation capability of R&D and the firm's performance by mainly comparing regional strategy industry with non-regional strategy industry. Also, this analysis involved comparing the relationship by regional strategy industry. For the purpose of this study, we divided innovation capability of R&D into input, process and output. The first of main results in this study was that regional strategic industry was significantly higher than non-regional strategy industry in innovation capability of R&D with the exception of the CEO's mind for technological innovations. However, we found no significant difference in the firm's performance. Second, in the results of comparing innovation capability of R&D and the firm's performance by regional strategy industry, electronic-information equipment industry was significantly superior to other industries. Third, it was found that the relationship between innovation capability of R&D and the firm's performance was different by regional strategy industry. Also, R&D manpower and R&D process were more significant factors affecting the firm's performance rather than R&D input and output.

• Journal of dental hygiene science
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• v.15 no.5
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• pp.603-611
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• 2015

This research is aimed at cutting off hearing loss and other harmful factors due to noise and providing basic material for noise reduction plan. As the research method, this research assessed noise by measuring acoustic pressure level and frequency in various situation of non-treatment and treatment. As the measurement result, average noise degree of high speed handpiece of non-treatment, ultrasonic waves scaler, and low speed handpiece showed 58~66 dB(A). Average noise degree of scaling of treatment, tooth elimination, and denture adjust showed 73~81 dB(A). The result is inferior to recognized standards of noise induced hearing loss. But the result of assessing this with (noise rating) NR curve was NR-73~78, which exceeded general workplace noise standard. This level can cause hearing loss when exposed to a long time. Therefore, treatment office noise during dental treatment can cause psychological and physical damage in dental clinic employees, and it is urgently required to establish systematic and active noise reduction plan.

• Journal of Korean Academy of Nursing
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• v.25 no.1
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• pp.45-60
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• 1995

This study investigated the effects of education program conducted through individual home visit by CHPs, which was developed ,by the operational re-search technique for families of dementia patients. (Yeo Shin Hong et at,1994) The study was conducted in the form of a primary experimental design with 43 people as subjects, including dementia patients and family member in several Myon areas of Chungcheong Namdo between June 10 and August 20, 1994. The data was collected by questionnaires through the home visit by the CHPs. The results of study are as follows. 1. There is no difference in the quality of life between before and after the education program. 2. Role stress 'before the education program' was significantly different than 'after the education program'. 3. There was no difference in the feeling of burden between before and after the education program. 4. There was a significant difference in the abnormal behaviors of patients between before and after the education program. 5. The knowledge of dementia by the patient's family increased significantly after the education program, compared to that of 'before the education program'. 6. There was a significant difference in the attitude of family members toward the education program on dementia between before and after the education program. 7. The results of analysis on the coefficient relationship of various variables showed that the age of patients and family members have a significant correlation with role stress(p=.01). 8. In the subjective evaluation of family members on changes in actual nursing actions and the improvement of knowledge and technique in terms of daily living, (including abnormal behavior of patients, adjustment of environment for patients, activity programs for patients, communication technique with patients, ensuring the safety of patients, clothing, meals and elimination, 60-65% of family members responded that their knowledge had increased. As for improvement in techniques for each item, the technique for communication with patients showed the greatest improvement while the action program method for patients showed the least change. As for the nursing service provided to patients, most respondents showed a positive change. The specific items for which more than 80% respondents answered positively were as follows : recognizing the demand of patients, getting patients to do simple house works, talking softly and gently, removing dangerous things, preparing comfortable clothes that are easy to put on and take off, and limiting water consumption at night. As a result of study, the following suggestions can be made. The purpose of the study was to examine the effect of an education program developed and applied for dementia patients and family members in the community. This needs to be compared with a similar study conducted in the urban setting. In addition, a community service program (ex : nursing hem and shelter) including the application of the education program should be developed and the study done to investigate its effect.

• Journal of Aquaculture
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• v.9 no.3
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• pp.239-245
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• 1996

As one of the red tide control method, montmorillonite was used to eliminate the causative organisms in Korea and Japan. We assayed the loess to replace the montmorillonite because it distribute in large quantity and nearby the red tide occurrence in South Coast of Korea. By using the mixture of loess and coal ashes, we examined the decreasing level of nutrients such as ammonia and phosphate, the elimination of causative organisms as a chlorophyll a content, and the harmful effect on aquaculture orgarnisms in cage culture farms. Half of the ammonium and phosphate was adsorbed by the loess particles, but only $25\%$ of ammonium was adsorbed by the coal ashes particles. In water column test, the particles of loess and coal ashes were settled down by $80\%$ in 20 minutes, the red tide organisms was eliminated by $80\%$ after 2 hours in 1,000 ppm of loess suspension, but the organisms were eliminated only $30\%$ by the same concentration of coal ashes. The harmful test of fishes and invertbrates, we observed any other negative effects of test animals than a tint deceleration in yellowtail.