• Title/Summary/Keyword: Critical period

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Re-contextualizing Urban Cultural Studies in Crisis -Linking with Fiske's Later Criticism of the City (위기의 도시 문화연구 재문맥화 -후기 피스크 비판적 공간 사유와의 접선)

  • Jeon, Gyuchan
    • Korean journal of communication and information
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    • v.70
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    • pp.35-65
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    • 2015
  • This paper is consisted of the thesis that the decontextualized limitation of media cultural studeis in Korea should be overcome by walking into and linking with today's urban crisis and everyday life. It proposes us to become the flaneurs who do not hesitate to go to, think of, and experience actively the city in crisis under the capital/state domination. It's conclusion would be that we must practice participation observation at the fields and thus recover the critical element of cultural studies writing, by entering into the city and seeing at the features of crisis routinely expressed and symptomatically appear in there. For and before this, the author will first of all pay attention to John Fiske in later period, who was merely perceived and falsely regarded as an active audience theorist. He will also review de Certeau from whom Fiske has borrowed the concept of tactics, and Berman who has further practiced the very spatial tactic. The paper is prepared so as to expand the ideas and thoughts of them who have gone beyond the boundary of text, audience and onto the context of urban space. It's goal is much more than rescuing, recovering Fiske's alternative trajectory. It tries to reconstruct the tradition of urban media cultural studies critically connected with the dangerous, life-threatening capitalist condition. Furthermore, by filling up the theoretical vacuum left behind disconnected and cut away from Fiske, it attempts to find a vision, prospect of cultural studies that will actively engage themselves dialectally with dangerous yet hopeful life of the city and its popular masses.

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THE EFFECT OF DIFFERENT SURFACE TREATMENT ON THE OSSEOINTEGRATION AND STABILITY OF IMPLANTS (처리 방법이 다른 표면이 임플랜트의 골유착 및 안정성에 미치는 영향)

  • Yang, Seoung-Wook;Lim, Heon-Song;Cho, In-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.44 no.5
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    • pp.606-616
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    • 2006
  • Purpose: This experiment examined the effect of different surface treatment on the osseointegration and stability of implants. Material and methods: In this study, 40 each of machined, SLA and RBM implants, which are the most commonly used implants, were implanted into the tibia of 20 normal rabbits using $OsseoCare^{TM}$. The rabbits were sacrificed after 1 week, 4 weeks, 8 weeks and 12 weeks for implant stability analysis, removal torque analysis, histologic and histomorphometric analysis. Result : ISQ showed significant difference between Machined and RBM at first week and at 4 weeks. There was significant difference between Machined and both SLA and RBM(p<0.05) but after 8 weeks there were no significant difference between each group. In the removal torque, RBM showd significantly higher values than SLA and Machined surface at 1st week. At 4th and 12th week, there was significant difference between Machined and SLA, RBM(p<0.05). In the bone to implant contact variable, there was no significant difference between each surface treatment method. In the Machined surface group, there was no significant difference between each time interval. but in SLA group, there were significant differences between the 1st week and 12th week and in RBM group, there were significant differences between the 1st week and 8th, 12th week and between 4th and 12th week(p<0.05). The bone area showed significantly higher values in SLA and RBM compared to Machined surface 1st and 8th week and significantly higher values in SLA than Machined surface at the 4th week(p<0.05). Conclusion: The roughened surface of implants showed positive effect in the early stages of implantation and assisted in bone formation After the bone formation stage, there was no statistical difference between Machined and roughened surface groups. In dental implantation, where initial stability is critical to the success of implants, the use of roughened surface implants should assist in reducing the healing period after implantation.

Impact of NIE on entrepreneurship and career awareness in Adolescent: Mediated effect of self-efficacy (청소년의 신문활용교육(NIE)이 기업가정신 및 진로인식에 미치는 영향: 자기효능감을 매개효과로 하여)

  • Kim, Yong-Ho;Kim, Jong-Keun
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.11 no.5
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    • pp.153-164
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    • 2016
  • It is critical for adolescents to foster self-efficacy, creativity, and adventurous spirit as well as plans for appropriate career path in order to become good members of society. During this adolescent period, newspapers will be a good learning material as they deliver various and timely information in refined language. In this paper, we analyzed the impact of NIE on development of self-efficacy, awareness of career path, and entrepreneurship through comparing adolescents who regularly read newspapers with those who do not. We came up with the following result after analysis of surveys (with a sample size of 283) that targeted middle school and higher grade elementary school students across Korea. We confirmed that reading newspapers has a positive impact on development of self-efficacy, awareness of career path, and entrepreneurship. More specifically, reading newspapers regularly has a positive impact on development of self-efficacy that subsequently has a positive impact on development of awareness of career path and entrepreneurship. Therefore, we found that simply reading newspapers regularly has a positive impact on development of self-efficacy, awareness of career path, and entrepreneurship with no special programs utilizing the newspapers. This is because various information and opinions in newspapers help adolescents to develop their own views, improve understanding and awareness of career, and development of sociality including creativity and adventurous spirit. There is the meaning as the first research that this research checks what the NIE of the adolescents affects the positive impact to not only the self-efficacy and career awareness but also entrepreneurship.

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Examining the Moderating Effect of Involvement in the Internet Purchase Decision Process (인터넷 구매결정과정에서의 관여도의 조절효과에 관한 연구)

  • Kwahk, Kee-Young;Ji, So-Young
    • Asia pacific journal of information systems
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    • v.18 no.2
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    • pp.15-40
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    • 2008
  • With the explosive growth of the Internet, Internet shopping malls have become recognized as one of the major purchasing channels for consumers, as well as one of the competitive distribution channels for companies that allow them to contact with customers without intermediaries. It has motivated information systems(IS) researchers to examine the factors influencing consumer behavior and the purchase decision process in the context of Internet shopping malls. Despite the extensive research that has been conducted on the purchase decision process of consumers in online shopping malls, the results have demonstrated a need for further understanding of consumer behavior due to the unique features of virtual space and the characteristics of online consumers. Previous studies from marketing and consumer behavior domains have suggested that the concept of involvement plays an important role in explaining consumers' purchase behavior. Despite the critical role of involvement and the explosive growth of e-commerce, little research has examined the role of involvement in the Internet shopping mall context. With this motivation, this study has two research objectives. First, it introduces and tests an theoretical model capable of better explaining consumers' intention to purchase in the Internet shopping mall context. The proposed model extends and integrates existing models on purchase intention by incorporating purchase experience, innovativeness, and perceived self-control as the consumer factors, along with perceived risk, information provision, and perceived price as the Internet shopping mall factors. Second, this study examines how involvement differences may affect consumers' intention to purchase. For this purpose, two factors from involvement theory, involvement type and involvement level, are introduced into the research model as moderating variables. In order to test the proposed model, the overall approach employed was a field study using the structural equation model. We developed our data collection instrument by adopting existing validated questions wherever possible. All question items were measured with a seven-point, Likert-type scale, with anchors ranging from 'strongly disagree' to 'strongly agree.' Two IS researchers reviewed the instrument and checked its face validity. We collected empirical data for this study over a period of two weeks from subjects who had purchase experiences through Internet shopping malls. A total of 473 complete and valid responses were obtained. We carried out data analysis using a two-step methodology with AMOS 4.0. The first step in the data analysis was to establish the convergent and discriminant validity of the constructs. In the second step, we examined the structural model based on the cleansed measurement model. The empirical results partly support the proposed model and identify the moderating effect of involvement differences. Theoretical and practical implications of the study are discussed, along with its limitations.

Numerical Simulations of Nonlinear Behaviors of Pulsating Instabilities in Counterflow Diffusion Flames (대향류 확산화염에서 맥동 불안정성의 비선형 거동에 대한 수치해석)

  • Lee, Su-Ryong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.9
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    • pp.859-866
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    • 2010
  • Nonlinear dynamics of pulsating instability-diffusional-thermal instability with Lewis numbers sufficiently higher than unity-in counterflow diffusion flames, is numerically investigated by imposing a Damkohler number perturbation. The flame evolution exhibits three types of nonlinear behaviors, namely, decaying pulsating behavior, diverging behavior (which leads to extinction), and stable limit-cycle behavior. The stable limit-cycle behavior is observed in counterflow diffusion flames, but not in diffusion flames with a stagnant mixing layer. The critical value of the perturbed Damkohler number, which indicates the region where the three different flame behaviors can be observed, is obtained. A stable simple limit cycle, in which two supercritical Hopf bifurcations exist, is found in a narrow range of Damkohler numbers. As the flame temperature is increased, the stable simple limit cycle disappears and an unstable limit cycle corresponding to subcritical Hopf bifurcation appears. The period-doubling bifurcation is found to occur in a certain range of Damkohler numbers and temperatures, which leads to extend the lower boundary of supercritical Hopf bifurcation.

Viral Hepatitis and Liver Cancer in Korea: an Epidemiological Perspective

  • Yeo, Yohwan;Gwack, Jin;Kang, Seokin;Koo, Boyeon;Jung, Sun Jae;Dhamala, Prakash;Ko, Kwang-Pil;Lim, Young-Khi;Yoo, Keun-Young
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.11
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    • pp.6227-6231
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    • 2013
  • In the past, hepatitis B virus (HBV) infection was endemic in the general Korean population. The association of HBV infection with the occurrence of liver cancer has been well demonstrated in several epidemiologic studies. While the mortality rates of liver cancer in Korea have decreased steadily over the last decade, the presence of hepatitis B surface antigen (HBsAg) in mothers remains high at 3-4%, and 25.5% of these HBsAg positive mothers are positive for hepatitis B e antigen (HBeAg). HBV infection caused almost a quarter of hepatocellular carcinoma (HCC) cases and one-third of deaths from HCC. These aspects of HBV infection prompted the Korean government to create a vaccination program against HBV in the early 1980s. In 1995, the Communicable Disease Prevention Act (CDPA) was reformed, and the government increased the number of HBV vaccines in the National Immunization Program (NIP), driving the vaccination rate up to 95%. In 2000, the National Health Insurance Act (NHIA) was enacted, which provided increased resources for the prevention of perinatal HBV infection. Then in 2002, the Korean government, in conjunction with the Korean Medical Association (KMA), launched an HBV perinatal transmission prevention program. The prevalence of HBsAg in children had been high (4-5%) in the early 1980s, but had dropped to below 1% in 1995, and finally reached 0.2% in 2006 after the NIP had been implemented. After the success of the NIP, Korea finally obtained its first certification of achievement from the Western Pacific Regional Office of the World Health Organization (WPRO-WHO) for reaching its goal for HBV control. An age-period-cohort analysis showed a significant reduction in the liver cancer mortality rate in children and adolescents after the NIP had been implemented. In addition to its vaccination efforts, Korea launched the National Cancer Screening Program (NCSP) for 5 leading sites of cancer, including the liver, in 1999. As a consequence of this program, the 5-year liver cancer survival rate increased from 13.2% (1996-2000) to 23.3% (2003-2008). The development of both the primary and secondary prevention for liver cancer including HBV immunization and cancer screening has been of critical importance.

Micelles in Physical Chemistry Laboratory. Surfactant Catalyzed Oxidation of Glycine by Acidic Permanganate

  • Pare, Brijesh;Kaur, Parwinder;Bhagwat, V.W.;Fogliani, Charles
    • Journal of the Korean Chemical Society
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    • v.48 no.2
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    • pp.195-202
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    • 2004
  • Micellar catalysis is an essential part of theoretical and experimental curricular. The sodium dodecylsulfate (SDS) catalyzed reaction between glycine and potassium permanganate in acidic medium is an ideal kinetic experiment for the secondary and undergraduate physical chemistry laboratory, to show the effect of micellar catalysis on rate of the reaction. The reaction is conducted both with and without SDS to observe the rate enhancement in the presence of surfactant. To show surfactant catalysis a plot between k and [SDS] is plotted. As surfactant catalysis is observed even before the critical micelle concentration of SDS, this pre-micellar catalysis can be understood in the light of positive co-operativity. The value of positive cooperative index (n) has been found to be 2.37. Further, dependence of the reaction rate on substrate and oxidant concentrations is also discussed. The reaction follows pseudo-first-order kinetics. The overall reaction is second order, with first-order dependence on both glycine and permanganate concentrations. The theory of surfactant catalysis is also discussed. With the conditions specified in the experiment, total reaction times are in 3~4 hours lab session, thus allowing several data sets to be acquired in a single laboratory period. Preparation of solutions and procedure is also given in detail.

Shipowner's Lost Profit and Its Claim resulted from Delay in Redelivery under Time Charter (정기용선계약에서 반선지연에 의한 선주의 상실수익과 손해배상청구)

  • Han, Nak-Hyun;Jung, Jun-Sik
    • Journal of Korea Port Economic Association
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    • v.23 no.3
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    • pp.29-51
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    • 2007
  • The purpose of this study aims to explore shipowner's lost profit and its claim resulted from delay in redelivery under time charter with the Achilleas case. In this case, the charterers submitted that there was an established prima facie measure of damages in cases of late delivery, namely the difference between the market rate and the charter-party rate for the period from the time when the vessel should have been delivered until the time of her actual redelivery. An award for lost profit in respect of a subsequent charter could only be made under the second limb because the charterers had not been told, at or before the making of the addendum, that the owners were going to enter into a subsequent fixture and that it was critical that redelivery take place on time. However, the owners said their losses that was a not unlikely consequence of the charterers' breach. There was no special rule that the first limb could only lead to damages calculated by taking the difference between the market and the charter-party rate for the overrun. To award damages in the Achilleas case on the basis of the difference between the market and the charter rate for the overrun would compensate the owners for only a fraction of the true loss caused by the breach.

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Ecological Studies on Pal'tang River-Reservoir System in Korea. 4. Dynamics on Inorganic nutrients, POM and Phytoplankton Succession in the Lower Stream Kyungan (팔당호의 생태학적 연구 4. 경안천 하류의 영양염 및 입자태 유기물 거동과 식물플랑크톤의 천이)

  • Hong, Sung-Su;Auh, Yun-Yeol;Han, : Myung-Soo
    • Korean Journal of Ecology and Environment
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    • v.35 no.1 s.97
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    • pp.1-9
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    • 2002
  • In order to understand the relationship between succession of phytoplankton community structure and inorganic nutrients and particulate organic matters, a one station in Kyungan stream in Korea during the dry season was chosen. Water samplings were carried out once a week from 18 August to 13 November 1993. The DIN concentration distributed always abundantly, however, phosphate and silicate gradually reduced during the period. Phytoplankton community had a peak chlorophyll a concentration of $90.6\;{\mu}g/l$ in late summer (21 August 1993) and a second peak of $29.7\;{\mu}g/l$ in autumn (2 October 1993). After then late autumn was characterined by relatively low chlorophyll a concentration of $15{\sim}16\;{\mu}g/l$. Seasonal fluctuation of chlorophyll a concentrations were correlated with measured POC and PON concentrations: phytoplankton blooming may be a major factor controlling POC and PON concentrations in this ecosystem. Phosphate plays an most important role as a limiting factor of phytoplankton growth. However, when Si/P ratio low, silicate may be a more critical limiting factor than phosphate. Shifts of P-limitation to Si- limitation the succession of dominant phytoplankton can in duce: diatom to cyanobacteria such as Anabaena, Microcystis and Oscillatoria.

Effect of Some Variation Factors on Dissipation of Tebuconazole in Grape (포도 중 Tebuconazole의 잔류성에 미치는 몇 가지 변동요인의 영향)

  • Han, Seong-Soo;Lo, Seog-Cho;Ma, Sang-Yong
    • Korean Journal of Environmental Agriculture
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    • v.23 no.3
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    • pp.142-147
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    • 2004
  • Dissipation pattern of tebuconazole was evaluated by establishing application methods of the fungicide, paper-bagging of grape during growth and washing of grape after harvest. Application times increased from three to five resulted in high levels of residues in grape. Tebuconazole in grapes was present in different residual patterns with periods after final treatment ranging from 7 to 25 days. Significant differences in the residual patterns were also found when tebuconazole was treated during three different application periods, possibly due to meteorological condition and/or grape growth during each period. At the range from 2.5 g to 7.5 g of grape granules, residues were higher in small-sized grape than in big-sized grape and were mostly distributed on the peel of the grapes. Paper-bagging was a critical factor for reducing the fungicide residue on the peel. flesh of bagged and no-bagged grape had very low level of residues, 0.01 mg/kg and 0.05 mg/kg, respectively. Residues on grape was effectively eliminated with the washing methods suggested, a consecutive sinking-washing system Using of detergent solution during washing showed maximum residue reduction from grape. The washing methods showed effective action on the removal of lower content providing complete elimination, or almost, of the residues.