• Journal of ILASS-Korea
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• v.8 no.1
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• pp.9-15
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• 2003

The liquid phase LPG injection (LPLI) system is considered as one of the next generation fuel supply systems for LPG, vehicles, since it can accomplish the higher power, higher efficiency, and lower emission characteristics than the existing mixer type fuel supply system. However, during the injection of liquid LPG fuel into the inlet duct of an engine, a large quantity of heat is extracted due to evaporation of fuel. A problem is that the moisture in the air freezes around the outlet of a nozzle, which is called icing Phenomenon. It may cause damage to the outlet nozzle of an injector. The frozen ice deposit detached from the nozzle also may cause a considerable damage to the inlet valve or valve seat. In this work, the experimental investigation of the icing phenomenon was carried out. The results showed that the icing phenomenon and process were mainly affected by humidity of inlet air instead of the air temperature in the inlet duct. Also, it was observed that the icing occurs first in the inlet of a nozzle, and grows considerably at the upper part of the nozzle inlet and the opposite side of the nozzle entrance. An LPG fuel, mainly consisting of butane, has lower latent heat of vaporization than that of propane, which is an advantage in controlling the icing phenomenon.

• Journal of Navigation and Port Research
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• v.30 no.2
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• pp.125-130
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• 2006

Waves, which are the main source of ship motions in a seaway, considerably affect the performance of a ship. The study of waves and their impact on ship motions within harbors is an important aspect of the design and operation of harbors. The prediction of incoming groups of waves is particularly important for evaluating ship motion within a harbor. Such a prediction makes it possible to evaluate ship safety more accurately. The wave transformation model reported here is applied to actual ports based on Boussinesq wave equations both non-linear and dispersive wave processes be considered in order to capture physical effects such as wave shoaling, refractions, reflection and diffraction in variable depth environments. The prediction of incoming groups of waves is particularly important for evaluating ship motion within a harbor, Such a prediction makes it possible to evaluate ship safety more accurately and provide safe wave informations for navigation. Furthermore, a wave information support system is proposed for entering ships as one technique for improving the safety of ship operations. This system predicts the run of waves and reduces the danger by identifying the most dangerous point near the harbor entrance at the small wave groups.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.3
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• pp.204-213
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• 2010

Test fishing was carried out using six kinds of different mesh sizes (20, 22, 24, 28, 35, 40mm) for springnet-pot to study bycatches according to the mesh size and catches survey was done for another one (mesh size : 22mm, entrance round : 350mm) in Geo-je & Tong-young waters of Korea. On the first sea experiment, it was thought that suitable mesh size of spring-net-pot catching conger-eel over 35cm with decreasing the catches of conger-eel (Conger myriaster) below 35cm was 24mm. On the second sea experiment, commercial catches were crabs (Charybdis bimaculata), octopus minor (Octopus variabilis) and others including conger-eel, and catches proportion was 60% of total catches weights. There was no big difference for the monthly catches. Self-consumption catches were 9 species including conger-eel below 35cm holding 50% of catches in the side of weights. There were 40% of bycatches for the catches weights and 63% for catches numbers in the 22mm mesh size of spring-net-pot having entrance round over 140mm. It showed that 50% of catches weights were discarded.

• Journal of English Language & Literature
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• v.64 no.2
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• pp.187-201
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• 2018

Horatio Alger's Ragged Dick (1868) betrays the economic and social system of nineteenth-century America through a self-reformative bootblack's quest for respectability. Being considered a space of constant danger, nineteenth-century New York City serves as a game board, and both visitors and residents of the city are supposed to avoid dangers while moving across its space. Dick Hunter, the juvenile protagonist of the novel, illustrates a street-child who starts his game of life from the backline of the game board. Continuing his quest for respectability, not only must he abandon the bad habits that he acquired as a street-child, but he also must avoid thieves and swindlers just like a tourist or like a player of nineteenth-century American board games. As Dick's social rise goes parallel with his movement in the city space, his entrance to a bank brings him the access to other respectable places, and a series of entrance turns him into a legitimate subject in the official system of the American society. While he continues his game of life successfully with the help of gentlemen patrons, in reality it is almost impossible for a disadvantaged player to escape the backline of the society. Thus, Dick's success story presents Alger's fantasy about the ideal economic system in which materials and persons are endlessly circulated.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.709-719
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• 2010

As the world has had a high recognition of security since 9/11 attacks in 2001, many countries and international organizations around the world are making strenuous efforts in establishing stronger security, centering on areas with high possibility of terrorist attacks. In particular, harbor facilities where a great deal of trade take place between countries, have high possibilities of becoming the objects of terrorist attacks and also of becoming places of trading objects and illegal items which might be leveraged for terror attacks. In this study, I have explained the current status of the harbor entrance system through existing documents, interviews and field trips to harbors and have also introduced improvement measures using RFID technology from the viewpoint of BP(Business Process). I expect that this study will be used as basic materials because I have studied the number of people entering harbors and working procedures for vehicle entrance, which have not been studied so far and also laid out various factors to be considered to introduce RFID technology.

• School Mathematics
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• v.19 no.2
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• pp.369-384
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• 2017

Current Mathematics of CSAT(College Scholastic Ability Test) faced with preparing the test system and test items according to the new curriculum. The discuss about how to construct the items and what form of items should be set was not conducted enough. To accord with these requirements, in this study, mathematics exams for university entrance in Taiwan are investigated. We look into General Scholastic Ability Test(GSAT) and Advanced Subjects Test(AST) in Taiwan. Those exams are analyzed in terms of exam system, mathematical contents, types of items, and so on. And then on the basis of this, we discuss implications on mathematics assessment type and contents, further mathematics learning.

• The Journal of the Korea Contents Association
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• v.13 no.3
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• pp.370-380
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• 2013

The research is basically designed to reveal a revisiting behavior for Chung Nam Dae which is inherently characterized sightseeing site. Distributional lag model is tentatively employed to analyze economic factors such as entrance fee and a different level of income. Empirical findings investigate that the revisiting behavior that is associated with a long run effect is more closely connected to the level of national income, but not the level of incomes in Chung Cheong region and Chung Buk province as well. As far as revisiting intention concerns, the entrance fee tends to affect to it by a shorter distributional lag, but the level of income affects to it by way of a pretty much longer distributional lags. To this end, perceived value for Chung Nam Dae should be exposed in order to induce a re-visitor. Such a goal could be attainable by taking care of its system for entrance fee, expanding facilities, re-branding, service improvement, and developing useful programs. Also, setting up an inter-connected networking system with a sightseeing site around is highly recommended.

• The Korean Journal of Pain
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• v.30 no.3
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• pp.192-196
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• 2017

Background: This study was planned to investigate the relationship between musculoskeletal problems, depression, and quality of life in students preparing for university entrance exams. Methods: A total of 180 students were included in the study, 104 were female (57.77%), and 76 were male (42.22%). Students were reached through the cram schools ("dershane") in Denizli. Musculoskeletal system problems, depression status, and quality of life were determined with the Musculoskeletal-Postural Discomfort Scale (MDS), Boratav Depression Screen Scale (Bordepta), and Short Form-36 (SF-36), respectively. Demographic data, daily study, and sleep duration were also recorded. Results: Students have moderate musculoskeletal discomfort. Musculoskeletal disorders and depressive symptoms are more observed in female students than male students (P = 0.000). The SF-36 results were significantly negatively correlated with the MDS and Bordepta scores. A significant positive correlation was found between musculoskeletal disorders and depression status (r = 0.351, P = 0.000). Sleep duration was negatively correlated with the MDS and Bordepta (r = -0.209, P = 0.005; r = -0.148, P = 0.047, respectively) and positively correlated with the SF-36 role limitation/emotional and social functioning subscales (r = 0.225, P = 0.002 and r = 0.191, P = 0.010 respectively). Conclusions: Musculoskeletal problems and depression status negatively affects general health status especially in female students who are preparing for university entrance examinations. Students should be informed about musculoskeletal problems by healthcare professionals and the study room, tables, and chairs should be arranged ergonomically. Further studies might be determined that why musculoskeletal disorders and depression status are more widely among female students.

• Journal of Korean society of Dental Hygiene
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• v.11 no.5
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• pp.649-657
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• 2011

Objectives : The purpose of this study was to research attitude and satisfaction of the students in the department of dental hygiene in Jeolla-do and Chungcheong-do. Methods : We surveyed 499 students at the department of dental hygiene at colleges. During the period from October 2 to October 30, 2009 using a self-administered questionnaires. The data were analyzed with chi-square, t-test and one-way ANOVA, person correlation coefficients and multiple regression using the SPSS 13.0 program. Results : As for entrance motive with Dental Hygiene, 63.9% of the employment and selection information was 36.3% by oneself. As for pre-knowledge before entrance about dental hygiene by grade(p<0.01), as for satisfaction in the department dental hygiene by regional groups(p<0.05), as for aptitude suitability by educational system(p<0.05), as for encourage of enter school by grade and regional groups(p<0.05), by educational system(p<0.01) were statistically significant. As for encourage of enter school, aptitude suitability, pre-knowledge before entrance about dental hygiene were positive relation to satisfaction in the department dental hygiene. Multiple regression analysis indicated with explanatory power of 30.8% about satisfaction in the department dental hygiene. Conclusions : This study reports that it is necessary to carry out further studies on the various educational process and development of program in college. Dental hygiene education for the whole man and for promote efficiency in the department of dental hygiene, should be positive information activity via various media get the correct information of a department choice.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.1
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• pp.68-78
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• 2006

In the past few years, considerable efforts have been directed towards the further development of Urea-SCR(selective catalytic reduction) technique for diesel-driven vehicle. Although urea possesses considerable advantages over Ammonia$(NH_3)$ in terms of toxicity and handling, its necessary decomposition into Ammonia and carbon dioxide complicates the DeNOx process. Moreover, a mobile SCR system has only a short distance between engine exhaust and the catalyst entrance. Hence, this leads to not enough residence times of urea, and therefore evaporation and thermolysis cannot be completed at the catalyst entrance. This may cause high secondary emissions of Ammonia and isocyanic acid from the reducing agent and also leads to the fact that a considerable section of the catalyst may be misused for the purely thermal steps of water evaporation and thermolysis of urea. Hence the key factor to implementation of SCR technology on automobile is fast thermolysis, good mixing of Ammonia and gas, and reducing Ammonia slip. In this context, this study performs three-dimensional numerical simulation of urea injection of heavy-duty diesel engine under various injection pressure, injector locations and number of injector hole. This study employs Eulerian-Lagrangian approach to consider break-up, evaporation and heat and mass-transfer between droplet and exhaust gas with considering thermolysis and the turbulence dispersion effect of droplet. The SCR-monolith brick has been treated as porous medium. The effect of location and number of hole of urea injector on the uniformity of Ammonia concentration distribution and the amount of water at the entrance of SCR-monolith has been examined in detail under various injection pressures. The present results show useful guidelines for the optimum design of urea injector for reducing Ammonia slip and improving DeNOx performance.