• Journal of Navigation and Port Research
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• v.36 no.3
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• pp.205-213
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• 2012

This study focused on the supply-demand and training system of the crew for domestic coastal shipping. First of all, it forecasted the prospect and effect in the future of the crew supply-demand through the analysis to the current situation of crew employment and the internal and external environment changes. Next, it suggested the specific role and alternatives of government, industry and educational institutions after the comparison and examination of the sailor policies among Korea and major shipping countries. In regard to the demand of crew manpower in coastal shipping, it figured out the bottoms and the current circumstances of sailors, and it could anticipate the future demand by the gradational approach. According to the findings, firstly the result of this simulation by the changes of the ship numbers demonstrated that the demand over the next 10 years will be 7,890~8,025 in the case of the growth 0.4%, and 7,894~8,063 in 0.5%. Secondly, assuming the growth 0.1~1%, the result illustrated that the demand will come to 7,879~8,258. This means the fact that the additional manpower has to be input to 20~430 annually from now on. To conclude, this study showed the more rational numbers about the supply-demand than the past researches and displayed the systematic approach to supply and train the crew in domestic coastal shipping.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.799-805
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• 2008

In general, anionic and cationic surfactants are incompatible because their mixtures form insoluble complexes and precipitate in the water. There are, however, some equimolar complexes of anionic and cationic surfactant that are soluble and behave like regular surfactants, specifically like nonionic surfactants, thus named pseudo-nonionic surfactant complexes. Pseudo-nonionic complexes are more effective and efficient in surface activities than their ionic surfactant components as shown by their equilibrium and dynamic surface tensions. They pack at the interface more than their ionic components. When a novel cationic surfactant, diglyceryl dodecyl dimethyl ammonium chloride(DGDAC), having the polyhydroxyl group at the hydrophilic head group, was mixed with a conventional anionic surfactant (sodium dodecyl sulfate; SDS) at equimolar ratio, we found that the aqueous equimolar mixture showed strong positive synergism in which molecular interaction parameter ${\beta}^M$ was very low, -17.2. According to the studies of equilibrium phase behavior and microscopy, this mixed system could form homogenous solutions containing vesicles.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.5
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• pp.377-382
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• 2007

Porous mineral coating have been fabricated and applied for basic research on their slow release action to a fertilizer. Feldspar was selected as raw mineral for the coating and two different particle sizes of powder were prepared. Slow-release action was estimated by using a potassium sulfate fertilizer. Spherical pellets were prepared with a pan-type pelletizer and then screened into sizes ranging 1.4 to 2.35mm. While the fertilizer pellets were rotated in the pelletizer again, the feldspar powder and 0.5% polyvinyl alcohol solution were simultaneously sprayed on the pellets. The fertilizer pellets coated with feldspar powder were fabricated. The pellets were heated to increase their strength and screened to sort by coating thickness. Potassium releasing tests were conducted for 40 days and the performance for slow-release action was estimated as functions of the heating temperature, coating thickness and raw mineral powder size. The Burst effect caused high initial releasing rate. Releasing kinetics was proportional to concentration of potassium in pellets. The pellet that was fabricated with $27.4{\mu}m$-sized feldspar and heated at $1050^{\circ}C$ showed a releasing rate of 43% on the 40th day.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.6
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• pp.157-165
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• 2020

Aiming at the development of neural network and self-driving data set, it is also an idea to improve the performance of network model to detect moving objects by dividing the data set. In Darknet network framework, the YOLOv4 (You Only Look Once v4) network model was used to train and test Udacity data set. According to 7 proportions of the Udacity data set, it was divided into three subsets including training set, validation set and test set. K-means++ algorithm was used to conduct dimensional clustering of object boxes in 7 groups. By adjusting the super parameters of YOLOv4 network for training, Optimal model parameters for 7 groups were obtained respectively. These model parameters were used to detect and compare 7 test sets respectively. The experimental results showed that YOLOv4 can effectively detect the large, medium and small moving objects represented by Truck, Car and Pedestrian in the Udacity data set. When the ratio of training set, validation set and test set is 7:1.5:1.5, the optimal model parameters of the YOLOv4 have highest detection performance. The values show mAP50 reaching 80.89%, mAP75 reaching 47.08%, and the detection speed reaching 10.56 FPS.

• Korean Journal of Community Nutrition
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• v.21 no.1
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• pp.65-74
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• 2016

Objectives: This study was performed to investigate the nutritional status, health conditions, eating habits and experience and demand for nutrition dietary management of senior citizens. And these data are formed foundation of development of nutrition dietary management education program and contents in welfare facilities for the aged. Methods: We visited 3 public health centers, 3 senior citizens centers, and 4 welfare centers in Seoul, Gyeonggi-do, Chungnam province, and Daejeon area and carried out interview by semi-structured questionnaire for senior citizens older than 65 years who use those facilities. Results: The study included 17%, 30.7% and 52.3% of senior citizens from public health centers, seniorcitizen centers and and welfare centers, respectively. The age range of 43.9% of the population was 65-74 years and and 56.1% were older than 75 years. We observed that 83.2% of subjects took some medicines due to diseases that they have and 58.0% took prescription medicines for hypertension. The thing that they considered the most when selecting food was 'the taste'(p<0.05). Regarding the level of practice to keep the dietary life, they answered more than 'average' for most of items but answered less than 'average' for lot of salt intake, drinking, exercise. For the experience of nutrition dietary life education, only 19.8% answered 'Yes' and the service for nutrition dietary life management showed the highest score in the demand for 'provide nutritious food'. For the size of consulting group for nutrition/dietary life education, the public health center and welfare center preferred a larger group size but the senior citizens center preferred a smaller group. With regard to who will carry out the consulting, the demand for dietitian was the highest and the operation type showed the high demand in the order of consulting, education. The contents that they want to have consultation in nutrition dietary life education were diet therapy for diseases and the ordinary diet therapy for health. Conclusions: This study suggested the management of nutrition dietry life necessitates qualitative measures according to the different types of welfare facilities. For these, it is in need of development of counseling and education program included therapy for disease. Above all, the policy to secure dietitian of welfare facilities for the aged to perform these should be achived.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.1
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• pp.23-27
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• 2006

Purpose: There are a few case reports on asymmetric vocal cord uptake on FDG-PET in patients with unilateral vocal cord paralysis, which could be a potential pitfall in the interpretation of FDG-PET images. We evaluated the metabolic activity of laryngeal muscles of patients with unilateral vocal cord paralysis in comparison to normal controls during both speech and silence. Methods: Eleven patients with unilateral vocal cord palsy (thyroldectomy=7, lung cancer=1, others=3) and 12 normal controls underwent FDG-PET with usual protocol. They were divided into two groups respectively; one group read books aloud for 20 minutes (phonation group) and the other kept silence (non-phonation groups) after FDG injection. Recent neck CT scan were co-registered with FDG-PET to produce PET-CT fusion images to elaborate small laryngeal muscles. Results: In patients with unilateral vocal cord palsy, contralateral non-paralyzed vocal cord showed hypermetabolism mainly on thyroarytenoid muscle, more intensely with phonation group ($SUV=5.88{\pm}2.65$) than with non-phonation group ($SUV=2.30{\pm}0.39$). Normal control subjects showed hypermetabolism ($3.68{\pm}0.96$) in interarytenoid muscle and symmetric mild hypermetabolism in both lateral cricoarytenoid muscles in only phonation group. Conclusion: FDG-PET with fusion images using CT scan in patients with unilateral vocal cord paralysis showed hypermetabolism of contralateral non-paralyzed thyroarytenoid muscle, suggesting compensatory action during phonation. Phonation durung FDG PET study enhanced FDG uptake on different laryngeal muscles between patients with unilateral vocal cord paralysis and normal subjects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.146-155
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• 2020

This study was conducted from December 26, 2018 to January 4, 2019 in order to analyze the effects of hospital internal marketing on job performance and loyalty based on nurses' perception. The participants were 250 nurses at general hospitals located in Gyeonggi-do. The results of this study are as follows: First, internal marketing in hospitals had a statistically significant effect on organizational and future vision, education and training systems, communication, organizational attributes, and job performance (F=29.118, p<.001). The training system, organizational and future vision, compensation and welfare system, and work management environment were found to have a statistically significant effect (F=38.671, p <.001) on loyalty, and the effect of job performance on loyalty was statistically significant (F=87.324, p<.001). Second, the relationship between hospital internal marketing based on nurses' perception and loyalty was found to have a statistically significant positive (+) effect on stage 1 job performance (p<.001) and a statistically significant positive effect on stage 2 loyalty (+) (P <.001). The third-level internal marketing regression coefficient was significant, and job performance was also significant (P <.001). Based on these results, there is a need for hospital management to strengthen internal marketing in order to increase performance level and loyalty among nurses.

• The Journal of Natural Sciences
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• v.9 no.1
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• pp.19-24
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• 1997

Using the PCR(polymerase chain reaction method), gone 1 of phage K11 coding for K11 phage RNA polymerase has been cloned and expressed under the control of lac promoter. K11 phage RNA polymerase was conventionally purified through the DEAE-sephacel and Affigel blue column chromatographies. The 0.2-0.3 M $NH_4Cl$ fractions of DAEA-sephacel column chromatography showed K11 phage RNA polymerase activity and further purification with Affigel blue column chromatography showed nearly single protein band on SDS-polyacryl amide gel. K11 phage RNA polymerase, which is one of the T7 group phage RNA polymerase (E. coil phage T7, T3 and Salmonella tyhimurium phage SP6 RNA polymerase), shares high degrees of homology with the other T7 group phage RNA polymerase. Previously we constructed T7 and SP6 promoter variants and revealed promoter specificity of T7 and SP6 RNA polymerase (Lee and Kang, 1993). To investigate the promoter specificity of K11 RNA polymerase in vitro K11 promoter activity was measured with SP6 promoter variants. The SP6 promoter variant share highest degrees of sequence homology with K11 promoter sequence show strongest promoter activity.

• Journal of Navigation and Port Research
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• v.39 no.1
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• pp.69-75
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• 2015

The concrete purpose of this study is to suggest actually a debt ratio to optimize the capital structure providing a kind of approach to estimate the proper debt ratio with an analytical model and empirical data in Korean shipping industry. The mathematical and analytical model is started from the first equation about ROE, return of net operating income on equity, with an independent variable, debt ratio. It is constructed with several parameters, ROS(return of operating income on sales), TAT(total assets turnover), and NFCL(net finance cost to liabilities). There could not be a certain relationship between debt ratio and ROS or TAT, while some correlation or causality between debt ratio and NFCL. In other words, most of firms with high debt ratio is likely to burden higher finance cost than others with low one. In this case, there is a linearity relationship between debt ratio and NFCL, so then the second equation considering this relation could be included within the analytical approach of this paper. To be short, if the criteria of adequate debt ratio has to be defined as some level of debt ratio to optimize ROE, the ROE could be illustrated as a quadratic equation to debt ratio from two equations. Next, this research estimated those parameters' numbers through the single regression method with data over 12 years of Korean shipping industry, and identified empirically the fact that optimal debt ratio would be approximately 400%. To conclude, if that industry's sales and operating incomes are stable, the debt ratio could be accepted until twice of 200% had forced in order to guarantee its financial safety in past time.

• Korean Journal of Community Nutrition
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• v.19 no.2
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• pp.122-132
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• 2014

Objectives: This study was conducted to investigate the vitamin D status and to determine the association between serum 25-hydroxyvitamin D [25(OH)D] concentrations and consumption frequencies of vitamin D rich foods in Korean adults and older adults. Methods: Subjects were 10,374 adults and 2,792 older adults participating in the 2008-2009 Korea National Health and Nutrition Examination Survey (KNHANES). Consumption frequencies of vitamin D rich foods were estimated by using a qualitative food frequency questionnaire (FFQ). Eleven food items such as beef, egg, mackerel, tuna, yellow corvina, pollack, anchovy, mushroom, milk, yogurt, and ice cream were selected as vitamin D rich foods based on previous research. Results: The proportions of deficiency (< 12 ng/mL), inadequacy (12-20 ng/mL) and sufficiency (${\geq}20ng/mL$) of serum 25(OH)D concentrations from June to November and December to May in adults were 8.8%, 42.3%, 48.8%, and 28.2%, 52.8%, 19.1%, respectively. The proportions of deficiency, inadequacy and sufficiency of serum 25(OH)D concentrations from June to November and December to May in older adults were 10.1%, 32.4%, 57.5%, and 24.1%, 45.4%, 30.5%, respectively. The mean serum 25(OH)D concentrations in adults were positively related to the consumption frequencies of mackerel, anchovy, all fish, milk and milk dairy products. The mean serum 25(OH)D concentrations in older adults were positively related to the consumption frequencies of yellow corvina and negatively related to the consumption frequencies of ice cream. Conclusions: Our results suggest that Korean adults were more deficient in serum 25(OH)D concentrations than older adults. The consumption of vitamin D rich foods may affect vitamin D status in Korean adults. Further studies are required to confirm these findings.