• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.26 no.3
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• pp.220-237
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• 2021

Since the functional importance of marine phytoplankton was firstly advocated from early 1880s massive data on the species composition and abundance were produced by classical microscopic observation and the advanced auto-imaging technologies. Recently, pigment composition resulted from direct chemical analysis of phytoplankton samples or indirect remote sensing could be used for the group-specific quantification, which leads us to more diversified data production methods and for more improved spatiotemporal accessibilities to the target data-gathering points. In quite a few cases of many long-term marine ecosystem monitoring programs the phytoplankton species composition and abundance was included as a basic monitoring item. The phytoplankton data could be utilized as a crucial evidence for the long-term change in phytoplankton community structure and ecological functioning at the monitoring stations. Usability of the phytoplankton data sometimes is restricted by the differences in data producers throughout the whole monitoring period. Methods for sample treatments, analyses, and species identification of the phytoplankton species could be inconsistent among the different data producers and the monitoring years. In-depth study to determine the precise quantitative values of the phytoplankton species composition and abundance might be begun by Victor Hensen in late 1880s. International discussion on the quality assurance of the marine phytoplankton data began in 1969 by the SCOR Working Group 33 of ICSU. Final report of the Working group in 1974 (UNESCO Technical Papers in Marine Science 18) was later revised and published as the UNESCO Monographs on oceanographic methodology 6. The BEQUALM project, the former body of IPI (International Phytoplankton Intercomparison) for marine phytoplankton data QA/QC under ISO standard, was initiated in late 1990. The IPI is promoting international collaboration for all the participating countries to apply the QA/QC standard established from the 20 years long experience and practices. In Korea, however, such a QA/QC standard for marine phytoplankton species composition and abundance data is not well established by law, whereas that for marine chemical data from measurements and analysis has been already set up and managed. The first priority might be to establish a QA/QC standard system for species composition and abundance data of marine phytoplankton, then to be extended to other functional groups at the higher consumer level of marine food webs.

• Korean Journal of Environmental Biology
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• v.41 no.3
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• pp.325-334
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• 2023

The invasive red swamp crayfish, Procambarus clarkii, is native to south-central United States and northeastern Mexico. Recently, it has been being spreading in the wild in South Korea. However, its primary sources, introduction routes, establishment, and expansion in South Korea remain unclear. Here, we analyzed genetic diversity and population genetic structures of its domestic natural populations during early invasion, commercial stock from local aquaria (a suspected introduction source), and original United States population using mitochondrial COI gene sequences for 267 individuals and eight microsatellite markers for 158 individuals. Natural and commercial populations of P. clarkii showed reduced genetic diversity (e.g., haplotype diversity and allelic richness). The highest genetic diversity was observed in one original source population based on both genetic markers. Despite a large number of individuals in commercial aquaria, we detected remarkably low genetic diversity and only three haplotypes among 226 individuals, suggesting an inbred population likely originating from a small founder group. Additionally, the low genetic diversity in the natural population indicates a small effective population size during early establishment of P. clarkii in South Korea. Interestingly, genetic differentiation between natural populations and the United States population was lower than that between natural populations and aquarium populations. This suggests that various genetic types from the United States likely have entered different domestic aquariums, leading to distinct natural populations through separate pathways. Results of our study will provide an insight on the level of genetic divergence and population differentiation during the initial stage of invasion of non-indigenous species into new environments.

• Journal of Korean Society of Transportation
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• v.22 no.7 s.78
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• pp.119-129
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• 2004

This paper is designed to report the results of development and validation procedures in relation to the Freeway Incident Management System (FIMS) prototype development as part of Intelligent Transportation Systems Research and Development program. The central core of the FIMS is an integration of the component parts and the modular, but the integrated system for freeway management. The whole approach has been component-orientated, with a secondary emphasis being placed on the traffic characteristics at the sites. The first action taken during the development process was the selection of the required data for each components within the existing infrastructure of Korean freeway system. After through review and analysis of vehicle detection data, the pilot site led to the utilization of different technologies in relation to the specific needs and character of the implementation. This meant that the existing system was tested in a different configuration at different sections of freeway, thereby increasing the validity and scope of the overall findings. The incident detection module has been performed according to predefined system validation specifications. The system validation specifications have identified two component data collection and analysis patterns which were outlined in the validation specifications; the on-line and off-line testing procedural frameworks. The off-line testing was achieved using asynchronous analysis, commonly in conjunction with simulation of device input data to take full advantage of the opportunity to test and calibrate the incident detection algorithms focused on APID, DES, DELOS and McMaster. The simulation was done with the use of synchronous analysis, thereby providing a means for testing the incident detection module.

• Journal of Nutrition and Health
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• v.49 no.3
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• pp.179-188
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• 2016

Purpose: This cross-sectional study aimed to document the dietary behaviors, dietary changes, and health status of female marriage immigrants residing in Gwangju, Korea. Methods: The survey included 92 female immigrants attending Korean language class at a multi-cultural family support center. General characteristics, health status, anthropometric data, dietary behaviors, and dietary changes were collected. Results: Mean age of subjects was 31.3 years, and home countries of subjects were Vietnam (50.0%), China (26.0%), Philippines (12.0%), and others (12.0%). Frequently reported chronic diseases were digestive diseases (13.2%), anemia (12.1%), and neuropsychiatry disorder (8.9%). Seventeen percent of the subjects was obese ($BMI{\geq}25kg/m^2$). Dietary score by Mini Dietary Assessment was 3.45 out of 5 points. Dietary scores for dairy foods, meat/fish/egg/bean intake, meal regularity, and food variety were low, and those for fried foods and high fat meat intake were also low. Thirty-three percent of subjects answered that they have changed their diet and increased their consumption of fruits and vegetables after immigration. Length of residence in Korea was positively associated with BMI and waist circumference. Length of residence tends to be positively associated with dietary changes and obesity as well as inversely associated with disease prevalence. Conclusion: The study shows that length of residence is inversely related to disease prevalence. However, this association is thought to be due to the relatively short period of residence in Korea and thus the transitional phase to adapting to dietary practices. As the length of residence increases, disease patterns related to obesity are subject to change. Healthy dietary behaviors and adaptation to dietary practices in Korea in female marriage immigrants will not only benefit individuals but also their families and social structure. Therefore, varied, long-term, and target-specific studies on female marriage immigrants are highly needed.

• KDI Journal of Economic Policy
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• v.31 no.1
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• pp.239-276
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• 2009

The paper investigates the possible relationship between earnings prediction by security analysts and special ownership ties that link security companies those analysts belong to and firms under analysis. "Security analysts" are known best for their role as information producers in stock markets where imperfect information is prevalent and transaction costs are high. In such a market, changes in the fundamental value of a company are not spontaneously reflected in the stock price, and the security analysts actively produce and distribute the relevant information crucial for the price mechanism to operate efficiently. Therefore, securing the fairness and accuracy of information they provide is very important for efficiencyof resource allocation as well as protection of investors who are excluded from the special relationship. Evidence of systematic distortion of information by the special tie naturally calls for regulatory intervention, if found. However, one cannot presuppose the existence of distorted information based on the common ownership between the appraiser and the appraisee. Reputation effect is especially cherished by security firms and among analysts as indispensable intangible asset in the industry, and the incentive to maintain good reputation by providing accurate earnings prediction may overweigh the incentive to offer favorable rating or stock recommendation for the firms that are affiliated by common ownership. This study shares the theme of existing literature concerning the effect of conflict of interests on the accuracy of analyst's predictions. This study, however, focuses on the potential conflict of interest situation that may originate from the Korea-specific ownership structure of large conglomerates. Utilizing an extensive database of analysts' reports provided by WiseFn(R) in Korea, we perform empirical analysis of potential relationship between earnings prediction and common ownership. We first analyzed the prediction bias index which tells how optimistic or friendly the analyst's prediction is compared to the realized earnings. It is shown that there exists no statistically significant relationship between the prediction bias and common ownership. This is a rather surprising result since it is observed that the frequency of positive prediction bias is higher with such ownership tie. Next, we analyzed the prediction accuracy index which shows how accurate the analyst's prediction is compared to the realized earnings regardless of its sign. It is also concluded that there is no significant association between the accuracy ofearnings prediction and special relationship. We interpret the results implying that market discipline based on reputation effect is working in Korean stock market in the sense that security companies do not seem to be influenced by an incentive to offer distorted information on affiliated firms. While many of the existing studies confirm the relationship between the ability of the analystand the accuracy of the analyst's prediction, these factors cannot be controlled in the above analysis due to the lack of relevant data. As an indirect way to examine the possibility that such relationship might have distorted the result, we perform an additional but identical analysis based on a sub-sample consisting only of reports by best analysts. The result also confirms the earlier conclusion that the common ownership structure does not affect the accuracy and bias of earnings prediction by the analyst.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.380-390
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• 2010

This research was conducted to investigate the consciousness of demander on National Forest Management System and to seek for solution to activate it by measuring the variables such as the extent of goal achievement on the system, the extent of importance on function of national forest, benefit for participation of the system, and the extent of importance on the system as well as the extent of demander recognition and intention of participation on the system like, Cooperative Forest Program and People's Forest Program. The target of this investigation is to categorize consumers of National Forest Management System (NFMS) into four types such as environmental organization that do not participate in the system, environmental organization that participate in the team, company to publish a white paper on environmental and local government. As a result, the intention of participation was showed in C Type (62.7%), among fields that respondents interested in participation were tree planting and forest tending (56.2%). However, the rest of the participants were reluctant participate in the NFMS due to more benefit (72.2%) of corporate social responsibility from other fields than those from the field utilizing forestry. If only, diverse facilities related to national forest and active supporting policy are provided by Korea Forest Service, social participation using forest resources would be considered. Although 61% among A Type recognized NFMS in advance, the prime reason for not utilizing are the problems with reserving place for participates in and the inconvenience to participate in on-site. Type D shows slightly high interest in People's Forest Program (3.69). Also, it shows high interest in Forest Recreation (4.15) and Forest Reports (3.90). Particularly, it indicates that GyeongGi-Do and GangWon-Do local government prefers Forest Experience, and Cheolla, ChungCheong and GyeongSang local government prefer Forest Reports. Based on the above study, we finally suggest that legal alignment of the system, and the provision of incentive for inducement of voluntary participation by Corporate Social Responsibility (CSR), and establishment of new exclusive nongovernmental organization be able to operate the system as the solution to activate NFMS in terms of the consumer.

• Journal of the Mineralogical Society of Korea
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• v.32 no.1
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• pp.51-61
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• 2019

Clay minerals, a major component of mud volcano (MV) sediments, are expected to provide important information for characterizing mud volcano formation mechanisms, but clay minerals have rarely been studied. The purpose of this study is to investigate the characteristics of 420 MV and surrounding marine sediments. Clay minerals and grain size were analyzed for 8 box cores from 420 MV and Mackenzie Trough. The relative proportions of the four major clay minerals in the Mackenzie Trough are almost constant in the order of illite, chlorite, kaolinite, and smectite, regardless of the distance from the Mackenzie River. However, the grain size tends to become fining as they move away from the Mackenzie River. Comparing the clay mineral characteristics of river (Colville River, Kuparuk River, Sagavanirktok River, Canning River, Mackenzie River) sediments entering the Beaufort Sea in order to determine the origin of the Mackenzie Trough and 420 MV sediments, the sediments of the Mackenzie Trough are characterized mainly by the Mackenzie River with a low ratio of smectite/illite and a high ratio of kaolinite/chlorite. In 420 MV sediments, the contents of clay minerals decrease in the order of illite, kaolinite, chlorite, and smectite, and the grain size with depth is almost constant. The content of smectite and coarse sediments is about two times higher than the reference core. No river with higher kaolinite content than chlorite exists in the Beaufort Sea, and the ratio of smectite/illite to kaolinite/chlorite is different from the reference core such as the ratio of the Mackenzie River. Compared to the reference core, the high contents of coarse sediments and the constant grain size with depth might be attributed to the ejection by MV. The reference core is interpreted as originating from Mackenzie River, and sediment of 420 MV is interpreted as originating from eruption of MV.

• Journal of The Korean Association For Science Education
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• v.25 no.7
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• pp.736-745
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• 2005

The purpose of this paper was to develop and execute self-appraisal test items on secondary science teachers. Test items included 6 sub-fields-subject knowledge, teaching strategies, teaching skills, assessment, laboratory management, and professional development - and 77 items. Using these test items, science teachers were able to evaluate their ability as prescribed by a 5-point Likert scale. Furthermore, teachers were able to comprehend fields showing their highest and lowest scores among the 6 sub-fields. They could then place special attention on the lowest field insuring self-growth as a science teacher. Self-appraisal test items were developed by analyzing related references on teacher evaluation criteria and standards. 220 subjects composed the sample on which these test items were executed. The results of this study were as follows. First, content validity of the test items was 80.8%. The range of sub-field reliabilities was .76 - .86 and the reliability coefficient of the entire test was .95. The range of correlation coefficient between each subfield was .54 - .69 and that of subfields and entire test was .54 - .79. The correlation coefficient between professional development and the whole test was .79, the highest coefficient observed. Second, significant difference was found according to teaching experience. More experienced teachers had higher scores in all 6 sub-fields (p<.05). In addition, a significant difference according to gender was observed in subject knowledge and laboratory management (p<.05); male teachers had higher scores than female teachers. Also, the higher the level of experience, the higher the scores for subject knowledge (p<.05). Lastly, the teacher's major did not result in any significant differences.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.919-924
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• 2005

This study was carried out to estimate the effects of parity, milking time, milking interval and days in milk(DIM) on variation in milk yield between consecutive milkings(am to pm to am), morning and evening milk yield and its components, somatic cell counts(SCS), milking duration, milk flow rate and peak milk flow in Holstein dairy cattle. Records from one hundred and twenty two heads of Holstein cattle at National Livestock Research Institute, Korea were used for this study from July 1 to August 8, 2005. The experimental herd had average 1.6$\pm$0.9 parities, 199.8$\pm$109.1 DIM and 12.26$\pm$4.06kg milk yields at each milking. Milking yield, percent milk fat and SNF, milking duration and average milk flow were significantly varied by parity, milking time and DIM. Percent milk protein and lactose were varied by parity and DIM, however SCS and average milk flow were affected by parity and milking time. Milking interval significantly affected the consecutive, morning and evening milk yield and average milk flow. However, MUN was not affected by parity, milking time, DIM and milking interval. Milk yield was decreased with increasing parity. Milk yield in the morning was higher than that of in the evening. Milk yield between consecutive milking was not affected by parity, however, affected by milking time. Percent milk Fat, SNF and SCS were higher at in evening milk than those of in morning milk. Milk protein, lactose, SNF, SCS, milking duration and peak milk flow rate were influenced by parity. This study suggested that milk yield variation between consecutive milking, milking flow rate, and milking duration could be important traits for enhancing Holstein cattle productivity however, and more study is needed to estimate genetic parameters for such traits.

• Journal of Korean Society of Forest Science
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• v.106 no.3
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• pp.288-299
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• 2017

This study was conducted to find out the influence of drought stress on physiological responses of Synurus deltoides. Drought stress was induced by withholding water for 25 days. Leaf water potentials were decreased of both predawn (${\Psi}_{pd}$) and mid-day (${\Psi}_{mid}$) with increasing drought stress, but water saturation dificit (WSD) was 7 times increased. ${\Psi}_{pd}-{\Psi}_{mid}$ showed the significant difference of 0.22~0.18 MPa in stressed before 10 days, and nonsignificant as treatment time became longer. A strong reduction of stomatal conductance ($gH_2O$) and stomatal transpiration rate (E) were observed after 15 days of drought stress Significant reductions of net apparent quantum yield (${\Phi}$) and maximum photosynthesis rate ($Pn_{max}$) were observed after 20 days of drought stress; However, water use efficiency (WUE) was shown the opposite trend. This implies that decrease of photosynthesis rate may be due to an inability to regulate water and $CO_2$ exchanged through the stomata. From JIP analysis, flux ratios (${\Psi}_O$ and ${\Phi}_{EO}$) and performance index on absorption basis ($PI_{ABS}$) were dramatically decreased withholding water after 15 days, which reflects the relative reduction of photosystem II activity. The leaf of S. deltoides showed osmotic adjustment of -0.35 MPa at full turgor and -0.40 MPa at zero turgor, and also cell-wall elastic adjustment of 9.4 MPa, indicating that S. deltoides tolerate drought stress through osmotic adjustment and cell-wall elastic adjustment. The degree of change in water relations parameters such as Vo/DW, Vt/DW decreased with increasing drought stress. This result showed that S. deltoides was exhibited a strong reduction of photosynthetic activity to approximately -0.93 MPa of predawn leaf water potential, and both of osmotic adjustment and cell-wall elastic adjustment in drought stress condition appears to be an important adaptation for restoration in this species.