• Journal of Advanced Marine Engineering and Technology
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• 제22권1호
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• pp.108-116
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• 1998

In this paper it is investigated the roles of key elementary reactions for NO formation in methane-air one-dimensional premixed flame and counterflow diffusion flame, which were studied numerically by using NO kinetics and $C_{2}$ -chemistry complied by Miller and Bowman. The spatial distributions of the reaction rates of 9 main elementary reactions directly related to NO formation and destruction were calculated. Integration of the rates of all reactions in the NO formation across the flame yields the quantitative reaction path diagram, which shows clearly relative importance of each reaction path in NO formation and how it changes with the type and parameters of the flame. The results show that the thermal and Fenimore mechanisms are dominant respectively for learn and rich premixed flames, and the latter is dominant for diffusion flames. In addition, it was found that the HCN recycle route is important for diffusion flame, and that the routes of mutual transformation between NO and NO$^{2}$, and between NO and HNO do not contribute to the net NO formation.

• 한국연소학회지
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• 제5권2호
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• pp.37-50
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• 2000

In the present study, a systematic chemical kinetic calculations were made to investigate the augmentation of $NO-NO_2$ conversion due to the addition of various hydrocarbons (methane, ethylene, ethane, propylene, propane) in the nonthermal plasma treatment. It is included in the present conclusion that the reaction between hydrocarbon and oxygen radicals induced by electron collision, is believed to be a primarily process for triggering the overall NO oxidation and the eventual NOx reduction. Upon the completion of the initiating step, various radicals (OH, $HO_2$ etc.) successively are produced by hydrocarbon decomposition form the primary path of $NO-NO_2$ conversion. When the initiating step is not activated, hydrocarbon consumption rate appeared to be very low, thereby the targeted level of NO conversion can only be achieved by the addition of more input energy. Present study showed ethylene and propylene to have higher affinity with O radical under all conditions, thereby both of these hydrocarbons show very fast and efficient $NO-NO_2$ oxidation. It was also shown that propylene is superior to ethylene in the aspect of NOx removal.

• The Journal of Asian Finance, Economics and Business
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• 제7권12호
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• pp.309-315
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• 2020

This study examines the accounting students' level of moral development at the university. In this study, we focused on the effects of ethics subject and gender on moral development. Therefore, we compare the moral development of male and female students. We evaluated 216 students in Cognitive Moral Development (CMD) from 17 universities in Indonesia. We measured CMD with the Defining Issues Test (DIT) model developed by Rest in 1986. The findings show that there is no difference in DIT scores between students who have taken the ethics subject and who have not taken. We also confirm female students have a higher DIT score than male students. Our study results show that gender plays an important role in the ethics issue. Our study strengthens the previous research about the effect of ethics study and ethics courses on CMD. This study has an implication for ethics education in university wherein the curriculum or the system should be prepared carefully. Although the results of this study did not show that ethics subject has a strong impact on students' CMD, we still believe that the ethics course plays a significant role in the accountants' morals. For that reason, we argue that morals need time to be developed, and cannot be taught in a short-term course. Future research is needed to explore more about this issue.

• East Asian mathematical journal
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• 제34권4호
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• pp.359-369
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• 2018

This note, we first show that the famous Carleman's inequality can be improved if we find a positive sequence $\{c_n\}$ such that $c_n{\sum\limits_{j=n}^{\infty}}{\frac{1}{j\(\prod_{k=1}^{j}ck\)^{\frac{1}{j}}}}$ < e. Then we list a lot of known results in the literature improving Carleman's inequality by this method. These results can be a good source to a further research for interested students. We next consider about similar improvement of Polya-Knopp's inequality, which is a continuous version of Carleman's inequality. We show by a manner parallel to the case of Carleman's inequality that Polya-Knopp's inequality can be improved if we find a positive function c(x) such that $c(x){\int}_{x}^{\infty}\frac{1}{t\;{\exp}\(\frac{1}{t}{\int}_{0}^{t}{\ln}\;c(s)\;ds\)}dt$ < e. But there are no known results improving Polya-Knopp's inequality by this method. Suggesting to find a new method, we lastly show that there is no nice continuous function c(x) that satisfies the inequality.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권1호
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• pp.1-8
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• 2001

This study was designed to localize the distribution of basic fibroblast growth factor(bFGF) in the developing rat condylar region and to elucidate the associated function of bFGF in the condyle development. The condyles of temporomandibular joint of Sprague-Dawley rats (27g of weight) were used. The tissues were examined with electron microscope and immunohistochemical method. The results were as follows: 1. The developing condylar region are divided in to 5 zones apparently: proliferative, maturation, hypertrophic, calcifying, and ossification zones. 2. The cells in the proliferative zone are condensed and have under-developed cell organells in the cytoplasm. This zone shows a strong immunoreactivity of bFGF. 3. The cells in the maturation zone are typical chondroblasts showing well-developed cell organells and round nucleus. The cartilaginous matrix does not show the immunoreactivity of bFGF, while the chondroblasts show the immunoreactivity. 4. The cells in the hypertrophic zone show hypertrophic change having the degenerated cell organelles and small nucleus. There are no immunoreactivity of bFGF in this zone except the nucleus and endoplasmic region showing mild immunoreactivity. 5, The cells in the calcifying zone show hypertrophic change and cell organelles are disappeared. The cells are surrounded by the calcified cartilaginous matrix. There are no immunoreactivity of bFGF in this zone except the endoplasmic region showing mild immunoreactivity. 6. In the zone of bone formation, chondroblasts are disappeared. Newly differentiated osteoblasts secreting osteoid around the calcified cartilaginous matrix. The bone marrow shows the immunoreactivity of bFGF, while the bone matrix does not show the immunoreactivity of bFGF.

• 한국연소학회지
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• 제4권2호
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• pp.63-74
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• 1999

The effects of EGR and premixedness on NO formation have been numerically investigated. The flame structure is classified into three categories; premixed flame($=1)$, rich/lean premixed flame(${\alpha}=0.6$ and 0.8) and diffusion flame(${\alpha}=0$). NO formation/destruction mechanisms are assorted to thermal, reburn and Fenimore mechanisms. The temperature of unburned gas is arranged to 298 and 500 K to have access to the condition in a real internal combustion engine. The results show that all three NO formation/destruction reaction rates in the fuel rich flame zone could be decreased by EGR for rich/lean premixed flames, while those in the fuel lean flame zone are not significantly changed. Near the stagnation plane, however, only the thermal NO reaction rate is decreased. The contribution of reburn and Fenimore mechanisms for the net NO production becomes less significant as the premixedness of a flame increases. The larger amount of NO reduction with EGR is expected under the higher temperature and/or higher fuel/air premixedness conditions due to the increased contribution of the thermal mechanism. The role of Fenimore and reburn mechanisms could be important for rich premixed and diffusion flames; therefore, the effect of EGR on NO reduction could vary with fuel/air premixedness. The premixedness of a partially premixed flame changes the flame structure and could affect the NO production characteristics.

• JSTS:Journal of Semiconductor Technology and Science
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• 제16권3호
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• pp.359-366
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• 2016

Today's multi-core technology rapidly increases with more and more Intellectual Property cores on a single chip. Network-on-Chip (NoC) is an emerging communication network design for SoC. For efficient on-chip communication, routing algorithms plays an important role. This paper proposes a novel multicast routing technique entitled as Docket NoC (Dt-NoC), which eliminates the need of routing tables for faster communication. This technique reduces the latency and computing power of NoC. This work uses a CURVE restriction based algorithm to restrict few CURVES during the communication between source and destination and it prevents the network from deadlock and livelock. Performance evaluation is done by utilizing cycle accurate RTL simulator and by Cadence TSMC 18 nm technology. Experimental results show that the Dt-NoC architecture consumes power approximately 33.75% 27.65% and 24.85% less than Baseline XY, EnA, OEnA architectures respectively. Dt-NoC performs good as compared to other routing algorithms such as baseline XY, EnA, OEnA distributed architecture in terms of latency, power and throughput.

• 한국안전학회지
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• 제10권2호
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• pp.105-112
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• 1995

The concentrations of $NO_2$ were measured to estimate a new developed long term exposure $NO_2$ sampler at Pusan City considering the meteorological factors from May to July, in 1994. The monthly mean concentration of $NO_2$ was 15.9 PPb and 36.2 ${\mu}\ell$/day $NO_2$ and their high values were shown in the downtown of Pusan City which show potential pollution due to the increase of traffic activities and micrometeorological factors In and around the City. As a result of statistical correlation between $NO_2$ concentration by new sampling method and $NO_2$ concentration by the handy air sampler and chemiluminescent nitrogen oxides analyzer, 1994, correlation coefficients were high(r=0.93) and showed more than 0.88 value in the high concentration data set, which was arbitrarily divided into 30${\mu}\ell$ $NO_2$ concentration in an attempt to further investigate these relationships. Therefore, use of new developed long term exposure $NO_2$ sampler is good for $NO_2$ measurement and valuable for estimation of air quality in the urban and Industrial area.

• 한국환경과학회지
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• 제25권2호
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• pp.191-216
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• 2016

Since prolonged exposure to elevated ozone ($O_3$) concentrations is known to be harmful to human health, appropriate control strategies for ozone are needed for the non-attainment area such as Seoul, Korea. The goal of this research is to assess factors linked with the 1-hour ozone exceedance through a decision tree model. Since ozone is a secondary pollutant, lag times between ozone and explanatory variables for ozone formation are taken into account in the model to improve the accuracy of the simulation. Results show that while ozone concentrations of the previous day and $NO_2$ concentrations in the morning are major drivers for ozone exceedances in the early afternoon, meteorology plays more important role for ozone exceedances in the late afternoon. Results also show that a selection of lag times between ozone and explanatory variables affect the accuracy of predicting 1-hour ozone exceedances. The result analyzed in this study can be used for developing control strategies of ozone in Seoul, Korea.

• Journal of Advanced Marine Engineering and Technology
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• 제27권5호
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• pp.657-665
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• 2003

Combined De-NOx Process in which $NH_3$ SCR (Selective Catalytic Reduction) and non-thermal Plasma Process are simultaneously used, has been investigated with a pilot test facility. The pilot test facility treats the combustion flue gases exhausted from a diesel engine that generates 240 kW of electrical power. Test results show that up to 80 % of NOx (NO and NO2) can be removed at 100 - $200^{\circ}C$. None of conventional De-NOx techniques works under such low temperature range. In addition to NOx. the Pilot test results show that soot can be simultaneously treated with the present non-thermal plasma technique. The present pilot test shows that the electrical power consumption to operate the non-thermal plasma reactor is equivalent to 3 - 4 % of the electrical power generated by the diesel engine.