• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.161-169
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• 1992

Studies were conducted to examine the effects of single or combined treatment of uniconazole [(E)-1-(4-chlorophenyl)-4, 4-dimethyl 2(1, 2,-4-triazol-1-yl)-1-penten-3-ol)] and silver thiosulfate (STS) on reducing ozone injury to snap beans (Phaseolus vulgaris L. 'Strike'). Two weeks after seeding, plants were given a soil drench of uniconazole(XE-1019) solution at concentrations of 0.001, 0.005 and 0.025 mg/pot, and then two days prior to ozone fumigation, 0.3 and 0.6 mM STS containing 0.01% Tween-20 were also sprayed. Uniconazole was effective in providing protection against ozone injury through increase activities of free radical scavengers such as superoxide dismutase (SOD) and peroxidase (POD) as well as the increase of chlorophyll content and stomatal resistance resulted from plant growth retardation. The phytoprotective effects of STS seemed to be related to its properly of blocking the ethylene action and increasing activities of SOD and POD. Even at low concentrations, a combined treatment with uniconazole drench, STS spray significantly reduced ozone injury compared to single application.

• Journal of Science and Technology Studies
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• v.14 no.2
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• pp.85-125
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• 2014

This paper explores what we call 'the problem of undone social science' by examining the lack of interests in the social, ethical, and legal issues of synthetic biology among social scientists in Korea. This new field of science, which has emerged in the twenty-first century with the promise of solving future problems of energy, food, and disease in the world, has also created a considerable degree of anxiety over the issues of bioethics, biosafety, and biosecurity. From its beginning, therefore, researchers of synthetic biology in Europe and the U.S. have sought to engage social scientists in their projects. Yet scientists and social scientists in Korea have shown no sign of working together to deal with both potential benefits and risks of synthetic biology. Why this silence? What strategic moves would be needed to overcome the structural barrier for their collaboration? Surveying the diverse methodologies developed during and after ELSI (ethical, legal, social implications) experiments, this paper aims to provide three suggestions that might make possible mutually profitable and continuously stimulating dialogues between the two worlds of science and social science: first, institutionalize the ELSI studies on any newly emerging science and technology of concern; second, explore diverse post-ELSI methodologies experimented elsewhere and develop ones that might be applicable best to the Korean situation; and third and perhaps most important, create an intellectual space and a lawful protection for social scientists to exercise their research freedom at the reasonable level and receive a fair review by their peers, not solely by funding agencies and scientific organizations.

• Journal of the Korean Chemical Society
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• v.47 no.1
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• pp.79-86
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• 2003

Misconceptions of students for a Voltaic cell were studied and their contents described in the high school chemistry II textbooks were analyzed. This study shows that students have many misconceptions and a few of chemistry textbooks contain some false description in a Voltaic cell. In the most textbooks, the reasons why the measured cell voltage of a Voltaic cell is near 1.1 V at the initial stage and then it decreases with time are not explained clearly. The emf of a Voltaic cell at a standard state is 0.76 V but in some textbooks it is described as 1.1 V of a Daniel cell. Even after learning the Voltaic cell or performing the experiment of textbooks, most students still have some misconceptions. These may be due to at least two following facts: the first is that the measured cell voltage of a Voltaic cell at the initial stage is very similar to that of a Daniel cell. The second is that the most experiment of a Voltaic cell is not performed under the condition of a standard state. Therefore, we have suggested a model of the modified experimental setup of a Voltaic cell that could reduce misconceptions of students.

• Journal of Service Research and Studies
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• v.10 no.3
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• pp.1-22
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• 2020

This study was conducted to derive the new manager model in service economy era. It was logically explained that the modern economic society is different from the existing economic society, the modern organization that is the subject of management is different from the existing organization, and the tasks required by management are different from the existing tasks. It suggested the managerial model required for new managers. According to the proposed manager's model, the tasks required of new managers and essential qualities as managers to perform the tasks were presented. It suggested the role model that managers with required qualities should play. The role of a manager who becomes one with customers, the role of a manager who controls even his irrationality, the role of a manager who combines discernment and indiscriminateness, a flexible leadership role that combines charisma and tenderness, an administrator role that embraces regulations and non-regulations, and vision and non-vision. We derived the role of a manager who manages management, and a manager role model that utilizes both competition and non-competition. The managers engage in two opposing roles and perform management activities in a spiral dialectical cycle that develops while resolving the contradictions of each role. The method of embracing the two opposing parties internally and externally and the dialectical management execution process according to the change of the space-time axis were presented by borrowing the models of The Book of Change. Future research needs an empirical analytical study on this new Model. There is a need for studies that expand this study and develop it into a practical model and verify it in an analytical way.

• Journal of Korea Water Resources Association
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• v.48 no.2
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• pp.91-103
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• 2015

This paper presents the systematic approach to positively skewed shape of instantaneous unit hydrograph (IUH), that is one of the universal features of hydrologic response function. To this end an analytical expression of statistical moments for IUH is derived within the framework of geomorphologic instantaneous unit hydrograph (GIUH) theory and quantified according to the concept of hydrodynamic, geomorphologic and kinematic heterogeneity. There is a big scale difference between hillslope and channel flow path system. Although the former has the much smaller level of scale its variation coefficient tends to be higher and coefficient of skewness has the different trend than the latter. The shape of IUH is likely to be much more affected by kinematic heterogeneity rather than hydrodynamic heterogeneity and its combined effect with geomorphologic heterogeneity is the major cause of skewing hydrologic response function. Statistical features of hillslope and channel flow path can be transferred into hydrologic response function in the form of dimensionless statistics and their relative importance forms the general shape of hydrologic response function.

• Journal of the HCI Society of Korea
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• v.5 no.1
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• pp.37-43
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• 2010

Twitter has been continuously growing since October, 2006. Especially, not only the users and the number of messages have been increasing but also a new concept in social networking called 'micro blogging' has diffused. Within Korea, service such as 'me2day' has already been introduced and the improvement of internet accessibility within mobile devices is expected to expand the 'micro blogs'. In this point, this research is executed to study the new medium, 'micro blog'. To do so, we collected and analyzed Twitter logs of Korean users. Especially, we were curious about the extreme heavy users using Twitter, despite of the linguistic and cultural barrier of the foreign service. Who they are, why and how they use the 'micro blog'. First, we reviewed the general aspect of followers and messages by collecting a certain number of random samples. Using the Lorenz curve we found out that there was the imbalance within the users and based on this phenomenon we deducted an extreme heavy user group. In order to perform further analysis, log analysis was performed on the extreme heavy users. As the result, the users used multiple mobile and desktop 'Twitter' clients. The usage pattern was similar to that of internet usage time but was used during their "micro" time. The users using 'Twitter' not only to spread messages about important information, special events and emotions, but also as a habitual 'chatting tool' to express ordinary personal chats similar to SMS and IM services. In this research, it is proved that 68% of the total messages were ordinary personal chats. Also, with 24% of the total messages were retweets, we were able to find out that virtually connected 'people' and 'relationships' acted as the dominant trigger of their articulation.

• The Korean Journal of Financial Management
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• v.8 no.2
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• pp.209-255
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• 1991

This paper develops a simple model to explain the reasons why foreign acquirers pay significantly higher premiums for U.S. target firms than do U.S. buyers. We also provide empirical work on the valuation effect of foreign takeovers and the determinants of the wealth gains of U.S. target shareholders involved in foreign takeovers. The results indicate that target wealth gains are significantly higher in foreign takeovers than in domestic takeovers, after controlling for the wealth effects of payment method, acquisition type, tax status, size and time period of bids. This confirms the valuation effect of foreign takeovers. Furthermore, the results of cross-sectional regression analysis show that the variation in U.S. target wealth gains is explained by extra tax benefits stemming from double tax deductions for acquisition-related interest expenses incurred by foreign acquirers. These findings imply that differential taxation across tax jurisdictions is the main source of the valuation effect of foreign takeovers. In addition, we find that there exists a valuation effect of the nationality of the foreign acquirers. Japanese companies pay significantly higher premiums than do non-Japanese acquirers. The finding also indicates that competition among bidders increases the abnormal returns to U.S. target shareholders in foreign takeovers.

• The Journal of Korean Medical History
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• v.12 no.2
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• pp.147-167
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• 1999

1. 연구 목적 한국의학사(韓國醫學史)의 한 분야인 식품사(食品史) 및 약물사(藥物史)는 미개척분야라 해도 과언은 아닐 정도로 연구 업적이 부족하다. 특히 식물명칭에 대한 정리는 기초학문이지만 방치되어진 것도 부인할 수 없다. 따라서 본고는 식품문화사(食品文化史)를 정리하는 과정중의 일환으로 고추의 어원(語源)을 중심으로 살펴보고자 한다. 이는 식품사(食品史) 연구에 도움이 되는 동시에 체질식이요법을 강조하는 사상의학(四象醫學)의 식품 분류에 대한 학술적 근거를 제시하는 계기로 삼고자 한다. 1493년 콜럼버스에 의해 알려진 고추는 우리 나라에 들어와 천초(川椒)대신 사용됨으로서 현재 중요한 양념이 되었다. 이에 고추의 도입과정과 호칭변화를 살펴봄으로서 현재 사전류에서 잘못 서술되고 있는 것을 시정하고, 고추가 도입된 이래 우리가 어떻게 이해하고 응용하였는 지에 대하여 문헌고찰을 통하여 의학사적(醫學史的) 입장으로 정리하는 것이 본 연구의 목적이다. 2. 연구 방법 "산림경제(山林經濟)"(1715), "임원경제지(林園經濟志)"(1827)같은 농서(農書), "물명고(物名考)"(1830), "오주연문장전산고(五洲衍文長箋散稿)"(1850) 같은 유서(類書), "훈몽자회(訓蒙字會)"(1527), "신증유합(新增類合)"(1574)같은 사전류, "지봉유설(芝峰類說)"(1614), "성호사설(星湖僿說)"(1763)같은 문집류, "흠정수시통고(欽定授時通考)"(1737), "본초강목습유(本草綱目拾遺)"(1765)같은 중국본초서(中國本草書) 등과 국내의서 등 을 통하여 고추에 대한 문헌정리를 시도하였다. 3. 연구 결과 고추가 도입된 이래 남만초(南蠻椒), 남초(南椒), 번초(番椒), 왜초(倭椒), 왜고초(倭苦椒), 왜개자(倭芥子), 고초(苦椒), 랄가(辣茄), 고쵸, 등으로 표기되어 왔다. 하지만 고추가 도입되기 전에 출간된 "구급간이방(救急簡易方)"(1489)에 '초(椒) 고쵸, 죠피'라는 기록이 나온다. 이는 천초(川椒)(초피나무)를 의미하는 '고쵸'로 보아야 한다. 후에 고추가 도입됨에 따라 의미가 변하여 고추를 의미하게 되는데 이를 정리하면 다음과 같다. 첫째, 현존하는 문헌 중 고추에 대한 최고기록인 "지봉유설(芝峰類說)"(1614)에 근거하여 고추(남만초(南蠻椒))는 임진왜란때 일본에서 도입되었다는 것이 정설이었다. 하지만 임진왜란 이전에 일본을 통하여 고추가 도입되었고 이의 개량종을 오히려 임진왜란때 일본으로 전해주었을 가능성이 높다. 둘째, 현재 대부분의 사전류에서 "훈몽자회(訓蒙字會)"(1527)의 '고쵸 쵸(초(椒))'를 고추에 대한 최초의 어원으로 보고 있으나 이는 잘못된 것이다. "훈몽자회(訓蒙字會)"의 '고쵸(초(椒))'는 고추가 아닌 매운 열매의 총칭으로 호초(胡椒), 천초(川椒), 진초(秦椒)를 의미한다. 이는 "구급간이방(救急簡易方)"(1489)의 천초(川椒)를 의미하는 '초(椒) 고쵸'에서도 확인할 수 있다. 셋째, 현재 대부분의 사전류에서 고추의 한문표기가 고초(苦草)로 되어 있으나 고초(苦椒)로 정정되어져야 한다. 초(草)(상성(上聲))와 초(椒)(평성(平聲))는 발음은 같지만 성조(聲調)가 다르며, 또한 "본사(本史)"(1787)에 고초(苦椒)와 고초(苦草)는 서로 다른 식물로 기록되어 있다. 넷째, 고초(苦椒)는 '고쵸'라는 우리말에 맞추어 만든 국자(國字)로 고추가 천초(川椒)와 비슷하지만 맵고 쓰다라는 뜻으로 사용된 것이다. 다섯째, 맵고 뜨거운 성질이 있는 고추는 냉증(冷症)을 유발시킬 수 있는 냉성(冷性)야채를 중화(中和)시키는 작용을 한다. 여섯째, 고추는 소음인 식품의 경향성을 띈 훈채류에 속한다.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.1
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• pp.81-96
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• 2007

Nonlinear shoaling characteristics over surf zone are numerically investigated based on spatially averaged NavierStokes equation. We also test the validity of gradient model for turbulent stresses due to wave breaking using the data acquainted during SUPERTANK LABORATORY DATA COLLECTION PROJECT(Krauss et al., 1992). It turns out that the characteristics length scale of breaking induced current is not negligible, which firmly stands against ever popular gradient model, ${\kappa}-{\varepsilon}$ model, but favors Large Eddy Simulation with finer grid. Based on these observations, we model the residual stress of spatially averaged NavierStokes equation after Lagrangian Dynamic Smagorinsky(Meneveau et al., 1996). We numerically integrate newly proposed wave equations using SPH with Gaussian kernel function. Severely deformed water surface profile, free falling water particle, queuing splash after landing of water particle on the free surface and wave finger due to structured vortex on rear side of wave crest(Narayanaswamy and Dalrymple, 2002) are successfully duplicated in the numerical simulation of wave propagation over uniform slope beach, which so far have been regarded very difficult features to mimic in the computational fluid mechanics.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.1
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• pp.49-54
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• 2003

This study was conducted to evaluate characteristics of particle composition and organic matter distribution for tidal flat sediments in the Saemankeum area. The tidal flat sediments consist of predominantly sand and a little of silt, whereas the content of clay was very low. The analyzed values of particles of tidal flat sediments were in the range of $4.60\~10.90\;{\phi}$ for mean size and $-0.1\~1.75\;{\phi}$ for sorting and $-1.0\~0.92\;{\phi}$ for skewness and $0.27\~6.75\;{\phi}$ for kurtosis. The tidal flat sediments are interpreted as representing significant effect of the environmental change due to the construction of Saemankeum embankment. The ORP was in the range of -133$\~$200 (mean 73) mV. But 24 stations of the total stations showed reduction condition, The concentration of CODs was in the range of 17.54$\~$6,176.3 mg/kg. The ratio of C/S was 0.02$\~$0.45 (mean 0.24). And the Saemankeum tidal flat sediment was a little effected by input organic pollutants from upper site area. Conclusively, conservation of the Saemankeum tidal flat sediment was requested because it is for the growing fishery and low organic matter.