• Journal of the Korean Electrochemical Society
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• v.15 no.2
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• pp.74-82
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• 2012

Proton exchange membrane fuel cell performance is changed by the complicated physical phenomenon. In this study, water discharge performance of proton exchange membrane fuel cell were performed numerically to compare serpentine channel flow fields of 5-pass 4-turn serpentine and 25 $cm^2$ reaction surface between with and without sub-channel at the rib. Through the supplement of sub channel flow field, it is shown from the results that water removal characteristic inside channel improves because the flow direction of under-rib convection is changed into the sub channel. Reacting gases supplied from entrance disperse into sub channel flow field and electrochemical reaction occurs uniformly over the reaction surface. The results obtained that total current density distributions become uniform because residence time of reacting gases traveling to sub-channel flow field is longer than to main channel.

• Electrical & Electronic Materials
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• v.9 no.5
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• pp.455-462
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• 1996

Automobile Fuel Shortage Detecting Sensor, in this paper, was fabricated by using heat dissipation coefficient difference between gasoline and air condition the NTC thermistor of Mn-Ni Co system with the composition ratio of Mn$_{3}$O$_{4}$ : 9wt%, NiO : 28wt%, and CO$_{3}$O$_{4}$ : 61wt%. The condition of sensor operation is that, for turn-on characteristics, the time of arriving at 135mA must be less than 180 second when the DC voltage of 11V is applied in the air condition of -10.deg. C and that, for turn-off characteristics, the saturation current must be less than 60mA when the DC voltage of 15V is applied in the gasoline condition of 60.deg. C. It is known, from the experimental results, that the resistance range and B-constant for the Automobile Fuel Shortage Detecting Sensor with dimension of 5*3*0.9mm were 850-1150.ohm. and 1150-1250.deg. C, respectively and the resistance range and B-constant were agree with that of sensor operation condition. When Bi$_{2}$O$_{3}$ of 0-0.5wt% was added to Mn$_{3}$O$_{4}$ : 9wt%, NiO : 28wt%, and CO$_{3}$O$_{4}$ : 61wt% composition, the resistivity and B-value were 380-430(.ohm.-cm) and 1930 - 2030, respectively. Particularly, for Bi$_{3}$O$_{3}$ of 0.25-0.5wt%, the sintering density of over 90% and the operation characteristics necessary to Automobile Fuel Shortage Detecting Sensor were obtained. The difference of heat dissipation coefficient gasoline and air condition was 15 times.

• Journal of the Korean Geographical Society
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• v.48 no.4
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• pp.557-574
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• 2013

The paper examines the recent criticism from various viewpoints on landscape research in 'New cultural geography' focusing on the representation and duplicity of landscape as one of the key theoretical basis of the landscape school. The paper argues that landscape theories in new cultural geography should be considered as what is constantly changing over time and composed of various theoretical and genealogical elements rather than internally homogeneous, fixed, and closed system of knowledge. Through the recent 'phenomenological turn' of geography, landscape researchers explores a possibility of alternative approach to the existing theories and methods, which is so called NRT(Non-representational theory). The research objectives of the paper is to examine the theoretical and practical implications of such significant criticisms, which put emphasis on the idea of landscape as performance and practice rather than landscape as representation in cultural geography.

• Asian review of World Histories
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• v.1 no.1
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• pp.5-44
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• 2013

This essay offers a historically based critique of the idea of "alternative modernities" that has acquired popularity in scholarly discussions over the last two decades. While significant in challenging Euro/American-centered conceptualizations of modernity, the idea of "alternative modernities" (or its twin, "multiple modernities") is open to criticism in the sense in which it has acquired currency in academic and political circles. The historical experience of Asian societies suggests that the search for "alternatives" long has been a feature of responses to the challenges of Euromodernity. But whereas "alternative" was conceived earlier in systemic terms, in its most recent version since the 1980s cultural difference has become its most important marker. Adding the adjective "alternative" to modernity has important counter-hegemonic cultural implications, calling for a new understanding of modernity. It also obscures in its fetishization of difference the entrapment of most of the "alternatives" claimed--products of the reconfigurations of global power--within the hegemonic spatial, temporal and developmentalist limits of the modernity they aspire to transcend. Culturally conceived notions of alternatives ignore the common structural context of a globalized capitalism which generates but also sets limits to difference. The seeming obsession with cultural difference, a defining feature of contemporary global modernity, distracts attention from urgent structural questions of social inequality and political injustice that have been globalized with the globalization of the regime of neoliberal capitalism. Interestingly, "the cultural turn" in the problematic of modernity since the 1980s has accompanied this turn in the global political economy during the same period. To be convincing in their claims to "alterity", arguments for "alternative modernities" need to re-articulate issues of cultural difference to their structural context of global capitalism. The goal of the discussion is to work out the implications of these political issues for "revisioning" the history and historiography of modernity.

• Journal of English Language & Literature
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• v.55 no.5
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• pp.907-936
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• 2009

Quite arguably, W. E. B. Du Bois is the first figure in the history of black nationalism who engaged most persistently and systematically with the dominant ideology of racism and white supremacy. It is not too much to say that, by contending with the Eurocentric but taken-for-granted concept of the 'Negro' in the turn of the century, Du bois has laid the theoretical and ideological cornerstone of postcolonialism today. But his concept of race varied over time and was even contradictory in the same writings. The early Du Bois defined race as something historically made rather than biologically given and determined. Yet he didn't utterly deny the significance of physical traits and skin color in constructing racial identity. His notion of the 'Negro' was not unambiguous, either. While drawing on the 'soul' of 'black folk' to undermine the Eurocentric dichotomy of white/mind and black/body, Du Bois argued that there is some kind of 'spiritual' differences between whites and blacks, differences that are essentially inherent and hereditary in the 'Negro.' Such essentialist notion of race and the 'Negro' was on the wane in the later Du Bois, especially after his encounter with Marxism. He came to think of race merely as a discourse of racism that can be subverted and even appropriated for anti-racist practices. Following the Marxist assumption that 'the color line' is a class conflict on the international level, Du Bois contended that the 'Negro' is an outcome of slavery which is in turn a subsystem of Western capitalism. He also argued that, since the 'Negro' is not a biological essence but a sociocultural formation, the identity of the 'Negro' can and must be reconstructed according to historical change. For Du Bois, therefore, the resistance against colonialism and capitalism became a resistance against racism. This is why his Pan-African movement shifted its gear from the American program in the initial phase to a truly 'Afrocentric' and socialist one.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.6
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• pp.559-565
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• 2016

For the purpose of the research, it is analyze the influence traffic Signal Progression on a CBD by expansion of Permissive Left-Turn on the advanced traffic management system program compared with traffic response control For this, divided a average distance between intersections, a traffic network on five district in four city. As the result, Volume of the traffic management system on a advanced traffic management system program compared with traffic response control is effective in traffic signal cycle 160sec 286car per lane, in 140sec 308car, 120sec 264car. As well, for a traffic network as the length of a traffic network 2.0~3.0km, under 2.0km, all of traffic signal cycle(160sec, 140sec, 120sec) a passing band and stop is more effective. But the traffic management system on traffic response control compared with the traffic management system on a advanced traffic management system program is effective in the length of a traffic network over 5.0km. For the efficiency of traffic signal system manage, it should be runned the traffic management system on traffic response control in addition to the traffic management system on a advanced traffic management system program on CBD. As the result of simulation the business in chungju-si, the travel speed of the traffic management system on a advanced traffic management system program is 41.2km/h and the travel speed of traffic response control is 37.5km/h. Therefore, it should be runned per length of a traffic network the traffic management system on traffic response control in addition to the traffic management system on a advanced traffic management system program on CBD.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.57-70
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• 2009

According to the change of the traffic conditions, the requirement of controlling the separated left(or right) turn, the median bus lane and bicycle signal is increasing. However, the traffic signal controller standard based on the four-set lights restricts to control the three-set lights which control the separated direction and kind of traffics. This study suggests the method to control the three-set lights signal by improving the hardware and software for the traffic signal controller which is operated currently in the traffic scene. The 6 output ports of Load Signal Unit(LSU) which is consisted of Pedestrian Red, Pedestrian Green, Red, Yellow, Arrow and Green signal reconstitute 2 rows of the Red, Yellow, Green for three-set lights while the Signal Map data's code values which control the signal step of an individual Ring and LSU are established to adjust the LSU's output ports(R1 Y1 G1 R2 Y2 G2) of the three-set lights. The effect of using the separated through/left turn and the median lane bus signal of three-set lights is analyzed from a Mangwoo intersection in Seoul. The results of analysis show that the delay time of the east-west direction where the median bus lane is operated is especially improved with over 70 sec/veh.

• Journal of Korean Society of Transportation
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• v.34 no.4
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• pp.291-303
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• 2016

The number of traffic accidents at intersections has been increased over the past decade, and in 2014, accounted for 44% of the total traffic accidents. In addition, since most of road accident black spots include signalized intersections, the improvement of safety on signalized intersection is top priority for national road safety program in Korea. For the decision of most effective action plan for the safety of signalized intersection, this study conducted meta-analyses to assess the effects of various road safety facilities at signalized intersection on traffic accidents. We selected 19 articles regarding the prediction of traffic accidents at signalized intersection and calculated 34 individual effect sizes on 8 variables included in the articles. The results found that there was a statistically significant negative relationship between the occurrence of traffic accident and the presence of all of road safety facilities except an exclusive left turn bay. It shows that most of the road safety facilities could prevent traffic accidents, and intersection channelization has the most effective on the reduction of traffic accidents followed by left-turn acceleration lane, lightning, crosswalk, exclusive right-turn lane and median barrier.

• Journal of Fashion Business
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• v.10 no.6
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• pp.52-62
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• 2006

The purpose of this study is to investigate the changes of modern Korean men's pants design from 1962 to 1998 by reviewing fashion magazine advertisements and pictorials. For theoretical study, the characteristics and the importance of apparel advertisements and the changes of modern Korean men's fashion trend were reviewed. For sample selection, first, 932 pictorials of men';s wear designs from Joongang Magazine, Shin Dong-A, Bokjangwolbo, Meot, Men's Life, WWD, and SFAA's photograph album, published from 1962 to 1998 were selected and then excluded some samples that could not clearly identify the pants design. Content analysis method was used to analyze the content of magazines and pictorials. The final samples are classified into pattern, color, length, silhouette, and existence or non-existence of turn-up. Frequency and $x^2$-test were conducted using a SAS statistics package to analyse the data. The results were as follows. ; (1) Solid pattern was the most prevailed throughout the last four decades and followed by stripe, check, the others, abstract, dot and floral. There is no significant difference in the type of men's pants pattern between each decade. (2) It showed a significant difference in colors of men's pants between decades. The colors in men's wear are divided into nine categories and the order of occurrence are as follows; multi-color is the most frequently shown and followed by brown, gray, blue, black, green, pink, yellow, and red. More various colors appeared over the period, however, multi color was the most popular in all decades but in the 60s. (3) Full length of pants style occupied more than 96% throughout all four decades. Due to the popularity of sports wear in men's fashion during the 90s, the shorts style appeared not only in sports wear and casual wear but also in suit style. (4) There is a significant difference in silhouette of men's pants between decades. The silhouette of men's pants were divided into four types and their order of occurrence are as follows; basic, baggy, fitted, and loose silhouette. Basic silhouette was the most prevailed throughout the whole four decades. (5) A significant difference was shown in the existence or non-existence of turn-up of men's pants between decades. Non-existence of turn-up of men's pants was the most prevailed throughout the whole four decades.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.76-82
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• 1990

In samples taken from mouth of the Nakdong River, mercury-resistant bacteria grown on the media supplemented with over 20 ppm of mercuric chlorice were below 0.3% of all aerobic heterotrophs. Among them, seven strains grown over 100 ppm of mercuric chloride were isolated and all were identified as Pseudomonas. The toxic effect of mercury on the growth of the most resistant strain N14 was influenced by the organic compounds and concentration. The growth and physiological activity to N14 strain were affected by toxic mercury in the early stage: The viable count and glucose turn over rate of N14 strain dropped to the lowest level as soon as the bacteria came into contact with mercury. During the extended lag period, however, bacteria accommodated to the stress and the viable count and glucose turnover rate increased. After the lag period, bacteria began to proliferate and their growth reached similar level to that of control. In crude extracts of N14 strain grown in nutrient browth containing. $10{\mu}M$ $HgCl_{2}$, a mercuric ion dependent oxidation of NADPH was demonstrated. Therefore the mechanism of mercury-resistance of the N14 strain involved the elimination of the mercury from growth media. In the N14 strain which a wide range of resistance to antibiotics was observed in, four multiple plasmids were detected. As a result, the supposition that N14 strain has a plasmid-encoded enzyme system may be quite within the realms of possobility.