• Journal of Advanced Marine Engineering and Technology
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• v.13 no.2
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• pp.43-63
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• 1989

Various kinds of corrosion prevention methods have been developed. It is known that the method of electrochemical protection is more effective and economical than any other method on the large scale metal structures in corrosive solutions. Strong acid solutions such as nitric and sulfuric acid solutions are often used in industries, and the expensive stainless steel is almost exclusively used for the equipment that comes in contact with such acid solutions. However, it is more reasonable that carbon steel is used rather than stainless steel depending upon concentration of those acid solutions from the economical viewpoint. In this study, the typical strong acid solution such as nitric and sulfuric acid solutions are chosen for the experiment and the selected materials of specimen are the stainless steels of SUS 304L and SUS 316L, the carbon steels of SS 41, SM 50 and RA 32, and highly pure lead. Electrochemical protection diagrams can be drawn with data from the external cathodic and anodic polarization curves of SUS 304L, SUS 316L and SM 50 steels in 5-60% nitric acid solutions and from those polarization curves of SS 41, RA 32, SM 50 and SUS 316L steels, and highly pure lead in 2.5-98% sulfuric acid solutions at the slow scanning rate. The data obtained with using the determination method of the optimum cathodic protection potential, the Tafel extrapolation method and the characteristics of anodic polarization curves. The main results obtained from the diagrams are as follows: 1) In nitric acid solution : (1) Corrosion potentials exist in each of those corrosion zones on the stainless steels in the lower concentration than about 12% solutions and on the high tensile strength steels in the lower concentration than about 30% solutions, but the corrosion current (density) in each zone is small on the above mentioned former steels and large on the latter ones. (2) The stainless steels can be self-passivated in the higher concentration than 15% solutions, and the high tensile strength steels gives rise to the same phenomenon in the higher concentration than 35% solutions. (3) The stainless steels in the lower concentration than 60% solutions and the high tensile strength steels in the higher concentration than 35% solutions can be used without protection, but the latter steels must ve protected anodically in the lower conccentration than about 30% solutions. 2) In sufuric acid solution : (1) The carbon steels can be self-passivated in the higher concentration than 45% solutions, and the SUS 316L steel in higher concentration than 75% solutions and the lead in all concentration solutions also gives rise to the same phenomenon. (2) The lead in the lower concentration than 80% solutions and the SUS 316L steel in the higher concentration than 80% solutions can be used without protection. (3) The carbon steels in the higher concentration than 50% solutions also can be used without protecting economically, but the SUS 316L steel in the 20-70% solutions are considerably corrosive without protecting anodically.

• Culinary science and hospitality research
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• v.15 no.1
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• pp.79-93
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• 2009

This study was conducted to suggest a way to increase profitability by figuring out the factors that affect the satisfaction and revisit intention of customers who visit a theme park, studying the property and correlation of service quality. The purpose of this study was to figure out the relation between the service quality of foods and beverages and its influence on the satisfaction of the customers who visited the theme park. As service quality and price of foods and beverages which occupy 20% of the whole sales of the theme park are related with each other, they positively affect the satisfaction of visitors of the theme park and their revisit intention. It means it is necessary to improve the service quality of foods and beverages and to set the reasonable price based on quality in order to raise the rate of the customers' revisit through increase in profits and customer satisfaction. One of the most important quality factors to improve service quality is service attitude of employees who help customers. It requires to take action to improve employers' morals and service mind via education and training. Thus, it is possible to raise customer satisfaction and revisit intention by improving service quality.

• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.414-421
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• 2000

This study was carried out for the artificial forest stand of 23 years old jack pine(Pinus banksiana Lamb.) in Soheul-myun, Pochun-kun, Kyunggi province of Korea. The objectives of this study were to investigate the stand volume increment and the rate of stand volume, and were to investigate present stand volume to determine annual cutting volume for keeping stand volume to an ideal level for investigated jack pine stand. For a reasonable calculation of stand volume increment, diameter of breast height(DBH), tree height, bark width, and core length for the last 10 years for respective sampling plots were measured. By using these measurements annual diameter increment in DBH class, stand volume increment of 95% confidence interval and tree height curve equation were calculated. The tree height value was derived from the tree height curve equation. Calculation of tree volume by using the tree volume table was made by conferring the tree height value. The summarized results for investigated jack pine trees were having 7.7% annual stand volume increment with 6.1% estimated error. The total stand volume per ha was $79.58m^3$, accordingly the annual stand volume increment was $6.13m^3$ per ha, and the 95% confidence intervals range from 5.77 to $6.51m^3$.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.3
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• pp.75-88
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• 2014

The purpose of this research is to provide the indication on policy for the SME that are going through the Growing Pains by analyzing the cause of the Growing Pains and the effect that it causes to the company performance. By measured the extent of the growing pains in entrepreneurial companies, 8 of the 20 companies surveyed companies indicate that some very significant problems exist within the organization and the other 12 companies indicate some organizational problems require attention. As a result of correlation between company performance and Growing Pains that analyzed by using CAGR(Compound Annual Growth Rate), we have arrived at the conclusion that they are oppositely related. We have conducted the regression coefficient in order to analyze the factors that are affecting the Growing Pains and we have discovered that Leadership and work performance capability of CEO, Company's structure capability and Company's cultural strength have a meaningful relation out of 7 Factors that were used for regression coefficient. Only, CEO's work performance is analyzed to worsen the Growing Pains that, for enterprises at the certain growing stage it is needed to establish an administrative system instead of relying on CEO. Also CEO's strong leadership play which relate to administrative capacity, forming reasonable organizational structure, customer oriented mind and Company's culture that are developed with sense of responsibility reduce Growing Pains according to a research.

• Geophysics and Geophysical Exploration
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• v.10 no.4
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• pp.353-360
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• 2007

We practiced fresh water injection test to identify its applibility as a method of seawater intrusion mitigation technique, and monitored the change of borehole fluid conductivity and the behavior of injected fresh water using borehole multichannel electrical conductivity monitoring and well-logging, and DC resistivity and SP monitoring at the surface. Well-logging and multichannel EC monitoring showed the decrease of fluid conductivity due to fresh water injection. We note that such an injection effect lasts more than several month which means the applibility of fresh water injection as a seawater intrusion control technique. Although SP monitoring did not show meaningful results because of weather condition during monitoring and the defects of electrodes due to long operation time, DC resistivity monitoring showed its effectiveness and applicability as a monitoring and assessment techniques of injection test by means of imaging the behavior and the front of fresh water body in terms of the increase of resistivity with reasonable resolution. In conclusion, we note that geophysical techniques can be an effective method of monitoring and evaluation of fresh water injection test, and expect that fresh water injection may be an practical method for the mitigation of seawater intrusion when applied with optimal design of injection well distribution and injection rate based on geophysical evaluation.

• Journal of Digital Convergence
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• v.15 no.4
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• pp.53-63
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• 2017

The purpose of this study is to look at the way that speech-to-text (STT) services are used at present, and to explore measures to institutionalize such services for ease of communication for the hearing impaired. The results of this study show the following: 1) 17.8% of those surveyed had experience of using STT services, with younger individuals showing a higher rate of use; and 2) In terms of organizations providing STT services, social welfare organizations followed by civic groups (18.3%) and public organizations (18.3%). The following institutional measures are needed for STT services. First, STT services should be actively promoted as one of the reasonable conveniences defined in the 'Act on the Prohibition of Discrimination Against Disabled Persons, Remedy Against Infringement of Their Rights, etc.' Second, STT services should be additionally listed as one of the clauses of the 'Act on Welfare of Persons with Disabilities'. In particular, establishing a communication system for those with hearing impairments should serve as a catalyst for integration with sign language interpretation and welfare services. If STT services for face-to-face contacts can be improved or further enhanced using ICT, it will not only open the way for a new influx of disabled workers to join vocational rehabilitation, but also help to improve quality of life for the hearing impaired.

• The Journal of the Convergence on Culture Technology
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• v.4 no.1
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• pp.193-200
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• 2018

This study is an experiential case study of cybercrime fraud that combines pharming and voice phishing in April 2017. Research on victims who have actually suffered in the study of crime or disaster is a very useful field in establishing crime prevention measures. This study is significant in that Korea is relatively poor in this kind of research. I got cyber fraud as a consequence of my loss of reasonable judgment due to mental confusion when a companion dog who was raised for 8 years was in a very dangerous situation with cystitis. Fortunately, I received all the damages in a quick report, but the period was eight months. It took too much time to get back all the damages, so I had to suffer another pain. Based on my experience, I suggest damage prevention measures. First, when a certain condition and a certain amount are transferred, the transaction is automatically stopped or a more strict confirmation procedure is added. Secondly, trafficking means to arrest the perpetrator without any harm to the victim is sought. Third, the victims of crime should be promptly reimbursed for damages or a system for lending their living funds to zero or lower interest rate.

• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.3 s.55
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• pp.1-10
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• 2007

In general, the tension forces of hanger cable in suspension bridges play an important role in evaluating the bridge conditions. The vibration method, as a conventional one, has been widely applied to estimate the tension forces by using the measured frequencies on hanger cables. However, the vibration method is not applicable to short hanger cables because the fiequencies of short cables are severely sensitive to flexural rigidity. Thus, in this study, the tension forces of short hanger cables, of which the length is shorter than 10 meters, were estimated through back analysis of the cable fiequencies measured from Gwang-An suspension bridge in Korea. Direct approach to back analysis is adopted using the univariate method among the direct search methods as an optimization technique. The univariate method is able to search the optimal tension forces without regard to the initial ones and has a rapid convergence rate. To verify the feasibility of back analysis, the results from back analysis and vibration method are compared with the design tension forces. From the comparison, it can be inferred that back analysis results are more reasonable agreement with the design tension forces of short hanger cable. Therefore, it is concluded that back analysis applied in this study is an appropriate tool for estimating tension forces of short hanger cables.

• Culinary science and hospitality research
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• v.21 no.5
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• pp.88-97
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• 2015

This study was conducted to evaluate the effect of Citrus peel powder on the quality characteristics of sponge cake. Citrus peel powder sponge cake was prepared with different ration of Citrus peel powder(0, 10, 20, 30, 40%). The specific gravity, baking loss rate and cake weight increases as the ratio of Citrus peel powder. The sponge cake's a, b level increased with the increasing level of Citrus peel powder 40% appeared to be the highest. In terms of textural characteristics, the samples containing 10, 20, and 40% Citrus peel powder had significantly higher hardness than the control samples. The substance's level of springiness, and cohesiveness decreased as the Citrus peel powder additive increased. In sensory evaluation, overall acceptability and taste of the cake was better than others when 10% Citrus peel powder was added. The results indicated that substituting 10% Citrus peel powder to sponge cake is optimal for quality and provides a product with reasonable high overall acceptability.

• Journal of Korea Water Resources Association
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• v.48 no.6
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• pp.451-461
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• 2015

This study aimed to estimate the future design rainfall through a non-stationary frequency analysis using the rainfall separation technique. First, we classified rainfall in the Korean Peninsula into local downpour and TC-induced rainfall through rainfall separation technique based on the path and size of a typhoon. Furthermore, we performed the analysis of regional rainfall characteristics and trends. In addition, we estimated the future design rainfall through a non-stationary frequency analysis using Gumbel distribution and carried out its quantitative comparison and evaluation. The results of the analysis suggest that the increase and decrease rate of rainfall in the Korean Peninsula were different and the increasing and decreasing tendencies were mutually contradictory at some points. In addition, a non-stationary frequency analysis was carried out by using the rainfall separation technique. The outcome of this analysis suggests that a relatively reasonable future design rainfall can be estimated. Comparing total rainfall with the future design rainfall, differences were found in the southern and eastern regions of the Korean peninsula. This means that climate change may have a different effect on the typhoon and local downpour. Thus, in the future, individual assessment of climate change impacts needs to be done through moisture separation. The results presented here are applicable in future hydraulic structures design, flood control measures related to climate change, and policy establishment.