• Journal of Korean Society of Environmental Engineers
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• v.34 no.4
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• pp.223-231
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• 2012

The purpose of this study is to investigate basically the mechanism of heat transfer by the resolution of complex fluid flow inside a sophisticated designed screw dryer for the treatment of sewage sludge by using numerical analysis and experimental study. By doing this, the result was quite helpful to obtain the design criteria for enhancing drying efficiency, thereby achieving the optimal design of a multiple screw type dryer for treating inorganic and organic sludge wastes. One notable design feature of the dryer was to bypass a certain of fraction of the hot combustion gases into the bottom of the screw cylinder, by the fluid flow induction, across the delicately designed holes on the screw surface to agitate internally the sticky sludges. This offers many benefits not only in the enhancement of thermal efficiency even for the high viscosity material but also greater flexibility in the application of system design and operation. However, one careful precaution was made in operation in that when distributing the hot flue gas over the lump of sludge for internal agitation not to make any pore blocking and to avoid too much pressure drop caused by inertial resistance across the lump of sludge. The optimal retention time for rotating the screw at 1 rpm in order to treat 200 kg/hr of sewage sludge was determined empirically about 100 minutes. The corresponding optimal heat source was found to be 150,000 kcal/hr. A series of numerical calculation is performed to resolve flow characteristics in order to assist in the system design as function of important system and operational variables. The numerical calculation is successfully evaluated against experimental temperature profile and flow field characteristics. In general, the calculation results are physically reasonable and consistent in parametric study. In further studies, more quantitative data analyses such as pressure drop across the type and loading of drying sludge will be made for the system evaluation in experiment and calculation.

• Management & Information Systems Review
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• v.33 no.5
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• pp.185-212
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• 2014

This study investigated the base of marine leisure facilities and studied the future vision for development of marine industry by conducting a systematic analysis on the category of marine leisure products for development of design and specialization of southeast area of Korea. If the age of $20,000 of per capita national income is called 'the age of my car', $20,000 of per capita national income is called 'the age of my boat'. According to the report of UK-based Marine South East, the scale of world's small boat and personal waterborne equipment reached 277 trillion won in 2010 and domestic market scale is expected to be 11 trillion won. Marine leisure facilities are the new growth engine industry that the government should promote as a nation's strategic and core industry, and the government is pushing ahead with promotion of marine industry actively by announcing Marine Leisure Equipment Industry Activation Plan(June 2009, Ministry of Knowledge Economy), Marine Leisure Activation Plan(July 2010, Ministry of Land, Infrastructure and Transport), The 1st General Plan for Marina Port(January 2010, Ministry of Land, Infrastructure and Transport) etc. The purpose of marine design lies in seeking the status of the country and qualitative value in human life through functional, artistic, industrial and cultural development of design elements for all marine activities made around the sea. Related to all activities made in the ocean and cost, marine design is a sphere of design that includes special conditions centering around water. Considering the condition that 3 sides of land are facing the sea, this study systematically analyzed present condition of equipment possessed by each area, type of facilities, operational status, current status of sectoral use of marine leisure facilities and future prospect of marine leisure products that become the basis of value to raise the statue as an advanced marine power in 2010s through development of the qualitative level of the people, establishment of the direction of national strategy, convergence of industry and culture and specialization of area focusing on the actual condition survey of marine leisure facilities. Especially, this study will be predicting the basis of strategy for strengthening marketability and competitiveness by suggesting role and process of design in developing a promising marine leisure product through an actual condition survey of marine leisure products of southeast area.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.1032-1042
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• 2011

The purpose of this study was to examine the attitudes and satisfaction level towards military foodservices as well as suggest effective ways to increase foodservice quality. A questionnaire survey was administered to 413 subjects, which included 400 soldiers and 13 foodservice managers. The survey period was from August 6 to August 25, 2008. The collected data were statistically treated using SPSS V12.0. Most of the investigated soldiers were 20~25 years old. The foodservice managers were male general officials and the majority of them had no prior food service training. None of the foodservice managers had a dietician certificate. Menu was planned through a local foodservice conference, and most food materials were delivered in the form of center-type and military unit-type. Deficiency and deterioration of food service facilities (28.6%) as well as deficiency in the number of cooking personnel (14.3%) increased the difficulty of operational management. Soldiers expressed a desire for increases in Western (25.7%) and Korean traditional foods (21.5%), which meant menu diversity. To increase the quality of military foodservices, taste of food (40.6%), increased portion size (30.4%), and improvement in hygienic conditions (13.6%) were demanded by the soldiers. Food taste (30.8%), improvement in hygienic conditions (23.1%), and better job management were all demanded by the foodservice managers. After factor analysis, quality attributes were rearranged into five dimensions, including facilities, food, menu, service, and sanitation most attributes were over 4 points out of 5 total in importance, but only 3 points in performance. The importance score was higher than the performance score. Soldiers' overall satisfaction level was on average 3.43 points out of 5 points.

• Korean Chemical Engineering Research
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• v.49 no.2
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• pp.256-262
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• 2011

Amine can undergo irreversible reactions by $O_{2}$ and high temperature in amine scrubbing process and these phenomena are called "degradation". Degradation causes not only a loss of valuable amine, but also operational problems such as foaming, corrosion and fouling. In this study, using various chemical absorbents(MEA; monoethanolamine, AMP; 2-amino-2-methyl-1-propanol, DAM; 1,8-diamino-p-menthane), we examined the following variable. I) loading ratio of $CO_{2}$ at $50^{\circ}C$ and $120^{\circ}C$, ii) concentration variation and initial degradation rate constant of absorbent in $CO_{2}$ and $CO_{2}/O_{2}$ system, and iii) effect of degradation by $O_{2}$. The $CO_{2}$ loading of 20 wt% DAM was 400% and 270% higher than that of 20 wt% MEA and AMP at 50, respectively and was the largest the difference of $CO_{2}$ loading between absorption $(50^{\circ}C)$ and regeneration $(120^{\circ}C)$ condition. The initial degradation rate constant of 20 wt% DAM was $2.254{\times}10^{-4}cycle^{-1}$ which was slower than that of MEA $(2.761{\times}10^{-4}cycle^{-1})$ and AMP $(2.461{\times}10^{-4}cycle^{-1})$ in $CO_{2}$ system. Also, it was increased 30% by $O_{2}$ that effects on the degradation by $O_{2}$ was less than 100% increased. these degradation reactions was able to identify by formation of new peak in GC and FT-IR spectrum analysis.

• Journal of National Security and Military Science
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• s.9
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• pp.313-340
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• 2011

The National Defense Reformation bill of "National Defense Reformation 2020" which have been constantly disputed and reformed by the government went through various levels of complementary measures after the North Korean sinking on the Republic of Korea (ROK) Naval Vessel "Cheonan". The final outcome of this reform is also known as the 307 Plan and this was announced on the 8th March. The reformed National Defense Reformation is to reduce the number of units and military personnel under the military structure reformation. However, in order for us to undertake successful National Defense Reformation, the use of privatized civilian resources are essential. Therefore according to this theory, the ROK Ministry of National Defense (MND) have selected the usage of privatized resources as one of the main core agenda for the National Defense Reformation management procedures, and under this agenda the MND plans to further expand the usage of private Especially the MND plans to minimize the personnel resources applied in non-combat areas and in turn use these supplemented personnel with optimization. In order to do this, the MND have initiated necessary appropriate analysis over the whole national defense section by understanding various projects and acquisition requests required by each militaries and civilian research institutions. However for efficient management of privatized civilian resources, first of all, those possible efficient private resources which can achieve optimization will need to be identified, and secondly continuous systematic reinforcements will need to be made in private resource usage legislations. Furthermore, we would need to consider the possibility of labor disputes because of privatization expansion. Therefore, full legal and systematic complementary measures are required in all possible issue arising areas which can affect the combat readiness posture. There is another problem of huge increase in operational expenses as reduction of standby forces are only reducing the number of soldiers and filling these numbers with more cost expensive commissioned officers. However, to overcome this problem, we would need to reduce the number of positions available for active officers and fill these positions with military reserve personnel who previously had working experiences with the related positions (thereby guaranteeing active officers re-employment after completing active service). This would in tum maintain the standards of combat readiness posture and reduce necessary financial budgets which may newly arise. The area of maintenance, supply, transportation, training & education duties which are highly efficient when using privatized resources, will need to be transformed from military management based to civilian management based system. For maintenance, this can be processed by integrating National Maintenance Support System. In order for us to undertake this procedure, we would need to develop maintenance units which are possible to be privatized and this will in turn reduce the military personnel executing job duties, improve service quality and prevent duplicate investments etc. For supply area, we will need to establish Integrated Military Logistics Center in-connection with national and civilian logistics system. This will in turn reduce the logistics time frame as well as required personnel and equipments. In terms of transportation, we will need to further expand the renting and leasing system. This will need to be executed by integrating the National Defense Transportation Information System which will in turn reduce the required personnel and financial budgets. Finally for training and education, retired military personnel can be employed as training instructors and at the military academy, further expansion in the number of civilian professors can be employed in-connection with National Defense Reformation. In other words, more active privatized civilian resources will need to be managed and used for National Defense Reformation.

• Journal of The Korean Association For Science Education
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• v.19 no.2
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• pp.239-247
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• 1999

This study is to make suggestion for developing textbook systematically by analyzing biological contents and organization in science textbooks which are important instructional media to accomplish objectives of the 6th middle school science curriculum. The inclusiveness degree of the 6th science educational objectives reflected in the textbooks was analyzed by Klopfer's and the Korean Educational Department's objectives taxonomy. And the biological contents and the organization of the science textbook were analyzed by learner, subject matter, and society dimensions which are selecting criteria for curriculum objectives suggested in Tyler's curriculum model. The analyzed results are as follows: 1. The inclusiveness degree of the educational objectives was very low. 2. Regarding the dimension of learner, the concepts of formal operational cognitive level were much increased as grade becomes higher. And the degree of learner's interests reflected on the learning topics and domains was very low. 3. Regarding the dimension of subject matter, the concept-centered learning was increased, in relation to inquiry learning as grade becomes higher. The analyzed results of inquiry subskills showed that observation, classification, and recording skills in 1st grade, observation and operation skills in 2nd grade, and interpreting data skills in 3rd grade were centered. As the problems and processes were presented, so most of inquiry activities had low openness scale. The learning contexts were organized into discipline-centered in relation to real life. 4. Regarding society dimension, the learning topics of environments and health were much presented. but those of biotechnology and career were presented scarcely. And most learning topics related society dimension were organized in textbooks of the 2nd and 3rd grade. These suggested that to accomplish curriculum objectives effectively. the inclusiveness degree of educational objectives is to increase and, the contents and organization of textbook were constructed harmoniously in aspects of learner, subject matter and society dimensions.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.5
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• pp.77-90
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• 2016

This study is to examine the importance of site selection and service quality in franchise business as food service franchise became one of the fastest-growing service industries today. The chief finding of this study is as follows: First, a survey in locational and service quality factors affecting food service franchise shows that responders are more concerned with hygiene and visibility of the store than proximity and transportation advantages which reflects low statistical significance, thus the distance did not seem to be a big problem for the responders in the context that they mostly visit nearby food franchise. Second, the examination of the influence by the service quality factors and customer satisfaction shows significant positive relation with customer response, speed and accuracy, and accuracy factors which reveals that the responders prefer prompt response and swift judgment toward the customer's needs and expectations, professional knowledge services to the credibility factors in which little correlation with the customer satisfaction were found. Third, the examination of the influence by the service quality factors, locational factors, and re-visit reveals that customer response and specialty showed statistically significant correlation with intention of WOM (Word of Mouth) and revisit, which suggests that swift judgment and response toward the customer's needs and expectations, professional knowledge services is of great importance to both customer satisfaction and revisit. The study on the aspects of locational and service quality factors affecting franchise industry's customer satisfaction was conducted as above, an investigation in both factors' influence on the customer satisfaction was made, and based on the results of the analysis, this research seeks an optimal operation strategy of a franchise business. Food service franchise are relatively very competent to business adminstration and reaction capability to consumption changes due to the already established market, and there are stores springing up everywhere inspired by the founders who are too confident of their success in the franchise business. However, it is necessary for the franchise beginners to figure out a zone oriented, regular customer oriented business strategy than just complying with the head office manual. Owing to an increasing trend of opening medium to large sized stores and investments in the wake of converting to multiple business type Korean food franchise, there is growing need to set up new concept of store development and operational management strategy in order to overcome the excessive competition and limited sales volume of the old-fashioned small sized, small capital franchise stores. Furthermore, as most business category of food service franchise serve very similar menus, from a product differentiation point of view, it is required to map out flexible sales concept including the adoption of competitive and low-price strategy. In conclusion, as is shown in the analytical research, the customers' optimal choice fluctuate over their preferences like customer convenience and circumstances rather than insisting on specific brand, thus it will be necessary for the franchise stores to draw up aggressive strategy and planning in running food service franchise to maximize their profits.

• The Journal of the Acoustical Society of Korea
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• v.37 no.4
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• pp.223-231
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• 2018

Recently, due to various environmental problems, blast tracks in tunnel are replaced with concrete tracks, but they have more adverse effects on noise than blast tracks so that additional noise measures are needed. Among these measures, sound-absorbing blocks start to be used due to its easy and quick installation. However, the performance of sound absorption blocks need to be verified under real environmental and operational conditions. In this paper, interior noise levels in KTX train cruising in Dalseong tunnel are measured before and after the installation of sound-absorbing blocks and the measured data are analyzed and compared. Additionally, noise reduction are estimated by modeling the high speed train, the tunnel and absorption blocks. Measurement devices and methods are used according to ISO 3381 and the equivalent sound pressure levels during the cruising time inside the tunnel are computed. In addition to overall SPLs(Sound Pressure Levels), 1/3-octave-band levels are also analyzed to account for the frequency characteristics of sound absorption and equipment noise in a cabin. In addition, to consider the effects of train cruising speeds and environmental conditions on the measurements, the measured data are corrected by using those measured during the train-passing through the tunnels located before and behind the Dalseong tunnel. Analysis of measured results showed that the maximum noise reduction of 6.8 dB (A) can be achieved for the local region where the sound-absorbing blocks are installed. Finally, through the comparison of predicted 1/3-octave band SPLs for the KTX interior noise with the measurements, the understanding of noise reduction mechanism due to sound-absorbing blocks is enhanced.

• The Journal of Society for e-Business Studies
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• v.25 no.1
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• pp.135-176
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• 2020

This study is to investigate the factors affecting the usage intentions of 5G service between 5G service subscribers and non-subscribers based on the Integratively Extended Technology Acceptance Model in the initial B2C 5G service market. We designed the integratively extended technology acceptance model to find the more specific factors to affect the usage intentions by integrating the exogenous factors including the technical factors, the social factors, and the personal factors with the ETAM(Extended Technology Acceptance Model). Referring to the previous studies, we constructed the hypotheses of structural influence relationship from the exogenous factors to the dependent usage intentions factors through the mediating belief factors. We designed the 5G service usage intentions model based on these hypotheses and operational definitions of the factors. Using the analysis of SEM(Structural Equation Model), the proposed model and the hypotheses were empirically tested by the data collected from 245 subscribed respondents and 245 non-subscribed respondents. As a result, the perceived ease of use has an effect on the perceived usefulness and enjoyment, and the perceived usefulness/enjoyment and the personal innovativeness have positive effects on the usage intentions of both groups.

• Journal of Elementary Mathematics Education in Korea
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• v.5 no.1
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• pp.99-120
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• 2001

The purpose of this thesis is to find the guiding direction of mathematical communication in lower grade students of elementary school and to present a new direction about the effect of using concrete material in communication. It is expected that mathematical communication increases when concrete material is used for the students of the lower grades, who are in concrete operational period. Therefore, this study ai s to investigate what characteristics there are in mathematical communication of second grade students and what effect concrete materials have on mathematical communication and learning. The analysis of the teaching record shows that the second grade students use alternative terms in the process of communication since they are not familiar with mathematical symbols or terms, which is a characteristic of communication in a mathematics class in which concrete material is used. In the process of teaming the students apply their living experiences to their teaming. Since a small number of students lead class, the interaction between students is also led by them. The direction of communication in a small group is not centered around solution of a problem, and most students show a more interest in finding answers than in the process of learning. The effect that concrete material has on communication plays an important role in promoting students' speaking activity; it allows students to identify and correct their errors more easily. It also makes students' activities more predictable, and it increases a small group activities through the medium of concrete material. However, it was also noticed that students' listening activities are not appropriately developed since they do not pay attention to a teacher who uses concrete material. The effects that concrete material has on mathematics class can be summarized as follows. Concrete material promotes students' participation in class by triggering their interest of learning of mathematics and helps them to understand the course of learning. It also helps the teaming and formation of concepts for children of low academic performance. And it makes a phased learning possible according to students' ability to use concrete material and to solve a problem. Based upon the results above mentioned, the use of concrete material is absolutely needed in mathematics classes of lower grade elementary school students since it increases communication and gives much influence on mathematics learning. Therefore, teachers need to develop teaching or learning method which can help increase communication, considering the characteristics of students' communication.