• Korean Journal of Ecology and Environment
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• v.51 no.2
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• pp.149-159
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• 2018

Twenty-nine wetlands (20 river type and 9 lake type wetlands) in Gyeongsangnam-do were investigated to understand the characteristics of fish assemblages by the wetland type and to suggest management strategies. As a result, $10.3{\pm}4.8$ species were collected from river type wetlands on average (${\pm}SD$) and $9.1{\pm}4.1$ species from lake type wetlands. Thus, there was no significant difference in the number of species between them (Mann-Whitney U test, P>0.05). However, the species that constitute the fish assemblage showed statistically significant differences between the two wetland types (PERMANOVA, Pseudo-F=2.9555, P=0.007). Furthermore, the species that contribute the most to each type of fish assemblage were Zacco koreanus (river type, 28.51%) and Lepomis macrochirus (lake type, 23.21%), respectively (SIMPER). The results of the NMDS analysis using the fish assemblage by place classified the species into three groups (river type, lake type, and others). The current wetland management is only focused on endangered species, but this study shows a difference in fish assemblage by wetland type. Therefore, a management system based information on endemic species, exotic species and major contribution species should be provided. Furthermore, the classification of some types of wetlands based on the present topography was found to be ambiguous, and wetland classification using living creatures can be used as a complementary method. This study has limitations because only two types of wetlands were analyzed. Therefore, a detailed management method that can represent every type of wetland should be prepared through the research of all types of wetlands in the future.

• Journal of Food Hygiene and Safety
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• v.33 no.1
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• pp.1-11
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• 2018

It is ten years since the Good Agricultural Practices (GAP) certification system was implemented in Korea, and the government aims to acquire GAP certification up to 25% of the total agricultural areas by 2022. As of the end of 2017, 6.3% of the total cultivated area and 8.1% of the total farm households were certified, which is slower than expected. The purpose of this study was to investigate the causes of the GAP accreditation through the surveys and on site inspections of the GAP certified farmers and to propose the development plans according to the problems analysis of the current system in order to expand the GAP certification. Certified farmers recognized the need for agricultural safety and hygiene, but there were a lot of nonconformities regarding practical practices. This is due to the ambiguity of the certification standards and the wrong ways in the training method for the producers. GAP certification is slow to expand to farmers and low consumer awareness is considered a structural problem of GAP certification system, and improvement measures are needed accordingly. It is necessary to convert the state-led GAP certification system into a state-led private certification system. It is necessary for the government to focus on policy, research and follow-up management. In addition, it is necessary to establish a separate organization in the form of a contribution organization for the certification, education, and public relations. In addition, long-term plan must be established and systematically carried out. It is necessary to integrate too many certification agencies compared to the farming scale of Korea, and it is necessary to realize the application fee for realizing the financial independence of the certification body and correct certification work. In addition, inspector qualification standards should be strengthened and training system should be improved to nurture high quality inspectors. Simplified certification standards based on statutes need to be subdivided into practical action plans. In order to improve the GAP certification system, it is necessary to have a discussion through a committee composed of specialists from industry and academia, and it will be possible to contribute to the safety of the food of the people through the production of safe by drawing concrete development plans.

• Korean Journal of Cognitive Science
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• v.28 no.4
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• pp.315-328
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• 2017

Even though assessment using information and communication technology will most likely lead the future of educational assessment, there is little domestic research on this topic. Computerized assessment will not only cut costs but also measure students' performance in ways not possible before. In this context, this study introduces a tool which can overcome the problems of multiple choice tests, which are most widely used type of assessment in current Korean educational setting. Multiple-choice tests, in which options are presented with the questions, are efficient in that grading can be automated; however, they allow for students who don't know the answer, to find the correct answer from the options. Park(2005) has developed a modified multiple-choice testing system (CMMT) using the interactivity of computers, that presents questions first, and options later for a short time when the student requests for them. The present study was conducted to find out if penalizing wrong answers could lower the possibility of students choosing an answer among the options when they don't know the correct answer. 116 students were tested with the directions that they will be penalized for wrong answers, but not for no response. There were 4 experimental conditions: 2 conditions of high or low percentage of penalizing, each in traditional multiple-choice or CMMT format. The results were analyzed using a two-way ANOVA for the number of no response, the test score and self-report score. Analysis showed that the number of no response was significantly higher for the CMMT format and that test scores were significantly lower when the penalizing percentage was high. The possibility of applying CMMT format tests while penalizing wrong answers in actual testing settings was addressed. In addition, the need for further research in the cognitive sciences to develop computerized assessment tools, was discussed.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.1025-1038
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• 2010

Carrot ($Daucus$ $carota$ L. var. $sativa$) is one of the most widely used crops in the world. Moreover it is an important crop because of its high content of ${\beta}$-carotene, well-known as the precursor of vitamin A carotenoid. However, seed-hair which is generated in epidermal cell of seeds inhibits absorption and germination. For that reason, carrot seeds are commercialized after mechanical hair removal process. To overcome such cumbersome weaknesses, new breeding program for developing hairless-seed carrot cultivar has been needed. Therefore, in this study, cDNA libraries from seeds of short-hair seed phenotype CT-ATR615 OP 666-13line and hairy seed CT-ATR615 OP-CK1-9 line were constructed and expression patterns related to generation of seed-hair were analyzed by comparison of EST sequences. Differential EST sequence results between two lines were classified into FunCat functional categories based on the results of BlastX search. Higher expression quantities belonging to metabolic category were shown on short-hair seed line than hairy-seed one. Differential expression quantities between those two lines in the protein folding and stabilization, subcellular localization categories were supposed to contribute variously on the generation of seed-hair. We confirmed 50 and 59 SSR sites, and 2 SNP sites by analyzing EST sequences in two lines; thereafter, we designed SNP and SSR primer sets from these EST sequence information as a molecular marker. These markers are thought to be used in research of molecular markers for classification of carrot family and related to various traits, as well as seed-hair characteristic.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.229-234
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• 2012

Disinfecting contaminated swine manure with FMD (Foot-and-Mouth Disease) and pathogenic viruses is very important for maintaining sanitized environment. However, very few research reported on this subject, especially post-disinfection to utilize the wastes as a renewable resource. This research is carried out to obtain basic information for chemical treatment in FMD SOP (Standard Operating Procedure, Korea) of contaminated swine manure. Using lime, sodium hydroxide, citric acid and hydrochloric acid, described in FMD SOP, the effects of chemical treatments on livestock manure were compared in this paper. Four combinations of alkali-acid treatments and four kinds of acid-alkali combinations were tested to find out the effective method. Total coliform bacteria in contaminated swine manure, $1.6{\times}10^4$ CFU/100 ml, decreased to the range of 1/1000~1/100 in all treatments. Some specific disinfectants increases BOD (Biochemical Oxygen Demand) and EC(Electric Conductivity), especially, alkaline treatments increases ammonia level than acid treatments. These findings suggest that the treatment methods should be considered as an important environmental factor in post-disinfection of contaminated animal manure with pathogenic microorganisms.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.4
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• pp.180-195
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• 2011

A balanced trophic model for Sinjido marine ecosystem was constructed using ECOPATH model and data obtained 1994 in the region. The model integrates available information on biomass and food spectrum, and analyses ecosystem properties, dynamics of the main species populations and the key trophic pathways of the system, and then compares these results with those of other marine environments. The model comprises 17 groups of benthic algae, phytoplankton, zooplankton, gastropoda, polychaeta, bivalvia, echinodermata, crustacean, cephalopoda, goby, flatfish, rays and skates, croaker, blenny, conger, flatheads, and detritus. The model shows trophic levels of 1.0~4.0 from primary producers and detritus to top predator as flathead group. The model estimates total biomass(B) of 0.1 $kgWW/m^2$, total net primary production(PP) of 1.6 $kgWW/m^2/yr$, total system throughput(TST) of 3.4 $kgWW/m^2/yr$ and TST's components of consumption 7%, exports 43%, respiratory flows 4% and flows into detritus 46%. The model also calculates PP/TR of 0.012, PP/B of 0.015, omnivory index(OI) of 0.12, Fin's cycling index(FCI) of 0.7%, Fin's mean path length(MPL) of2.11, ascendancy(A) of 4.1 $kgWW/m^2/yr$ bits, development capacity(C) of 8.2 $kgWW/m^2/yr$ bits and A/C of 51%. In particular this study focuses the analysis of mixed trophic impacts and describes the indirect impact of a groupb upon another through mediating one based on 4 types. A large proportion of total export in TST means higher exchange rate in the study region than in semi enclosed basins, which seems by strong tidal currents along the channels between islands, called Sinjido, Choyakdo and Saengildo. Among ecosystem theory and cycling indices, B, TST, PP/TR, FCI, MPL and OI are shown low, indicating the system is not fully mature according to Odum's theory. Additionally, high A/C reveals the maximum capacity of the region is small. To sum up, the study region has high exports of trophic flow and low capacity to develop, and reaches a development stage in the moment. This is a pilot research applied to the Sinjido in terms of trophic flow and food web system such that it may be helpful for comparison and management of the ecosystem in the future.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.172-179
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• 2017

The purpose of this study is to analyze the current original habitat and to conserve the narrow-mouthed toad populations. For this study, we used 240 pitfall traps (30 cm height ${\times}$ 20 cm width) to catch the narrow-mouthed toads that inhabit in Myeongji-dong, Gangseo-gu, in Busan metropolitan city from August 2, 2013 to November 7, 2013. We measured the environmental characteristics (soil composition factors, soil moisture, Humidity, soil temperature) for the seven habitat patterns of narrow-mouthed toads based on vegetation types. Main habitats of narrow mouthed toads were flat grassland where grass and false acacia grew and there was wetland all over the place. When analyzing habitats that main habitats of narrow-mouthed toads prefer after selecting representative seven vegetation, it was found that the most narrow-mouthed toads were caught in amur silver grass colony while the least narrow-mouthed toads were caught in bare land. Totally, we caught 846 narrow-mouthed toads over 68 times, and released them into the newly constructed habitat after injection VIE-tag. It seems that the reason for which the least narrow mouthed toads were caught in bare land is that bare land is not suitable for narrow mouthed toads to protect themselves from strong sunlight and to hide themselves from natural enemy. We found that temperature had the greatest influence on activities of narrow mouthed toads and at temperature of less than $15.6^{\circ}C$. We also found that the activities of narrow mouthed toads were remarkably low and then temperature was below $15.6^{\circ}C$. It meant that narrow mouthed toads seemed to go into hibernation. From this research, we could find the prefer habitat after analyzing habitats for the narrow-mouthed toads and could suggest for construction for the better habitat of narrow-mouthed toads.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.720-725
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• 2013

When highly shrinkable materials such as coir dust are major component of root media, the degrees of compaction during container filling of root media severely influences the physical properties of root media. It results in the changes in total porosity (TP), container capacity (CC) and air-filled porosity (AFP). This research was conducted to secure the fundamental information in changes of soil physical properties as influenced by the compaction of root media during container filling. To achieve this, three root media were formulated by blending coir dust (CD) with expanded rice hull (CD + ERH, 8:2, v/v), carbonized rice hull (CD + CRH, 6:4) and ground and raw pine bark (CD + GRPB, 8:2). Based on the optimum bulk density, the amount of root media filled into 6.0, 7.5, 8.5, 10.5 and 12.5 cm were adjusted to 90, 100, 110, 120 and 130% based on the weight of root media. Then the changes in TP, CC, and AFP were measured. Elevation of the packing amount of root media in all sizes of pot resulted in the decrease of TP. But the decrease was more severe in CD + ERH and CD + CRH than those in CD + GRPB. The CC also decreased gradually as the packing amounts were elevated in three root media, but the decreases were severe as the container sizes became larger. The AFP decreased drastically by the elevation of the packing amount of root media in all sizes of pot. The AFP was the highest in CD + CRH medium when pot sizes were smaller than 7 cm, but that was the highest in CD + ERH when the pot sizes were larger than 8.5 cm among the 3 root media tested. In this research, the elevation of packing amount of three root media influenced more severely the AFP rather than CC. This result indicates that the packing amount should be controlled to maintain appropriate level of AFP because AFP rather than CC influence severely crop growth. The results obtained through this study can be used to predict the changes in physical properties of root media as influenced by packing amount in various sizes of pots.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.2
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• pp.107-117
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• 2004

If doubtlessly contributes much to agriculture and rural development. The roles can be summarized as; 1. to activate rural areas and to provide more comfortable and safe rural life with equivalent services to those in urban areas, facilitating distance education, tole-medicine, remote public services, remote entertainment etc. 2. To initiate new agricultural and rural business such as e-commerce, real estate business for satellite officies, rural tourism and virtual corporation of small-scale farms. 3. To support policy-making and evaluation on optimal farm production, disaster management, effective agro-environmental resource management etc., providing tools such as GIS. 4. To improve farm management and farming technologies by efficient farm management, risk management, effective information or knowledge transfer etc., realizing competitive and sustainable farming with safe products. 5. To provide systems and tools to secure food traceability and reliability that has been an emerging issue concerning farm products since serious contamination such as BSE and chicken flu was detected. 6. To take an important and key role for industrialization of farming or lam business enterprise, combining the above roles.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.310-317
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• 2014

This study was conducted to find basic information for the research of morphological dormancy in seeds of two genera (Heloniopsis and Thalictrum) native to Korea. Seeds of Heloniopsis koreana, Heloniopsis tubiflora, Thalictrum rochenbrunianum, Thalictrum uchiyamai, and Thalictrum coreanum were collected, and embryo morphology and seed germination were investigated. All seeds of five species had underdeveloped embryos which occupied about 10-20% of the full seed length at maturity. The seeds of H. koreana and H. tubiflora had rudimentary embryos. The seeds of T. rochenbrunianum, T. uchiyamai, and T. coreanum had intermediate type between rudimentary and linear embryo. The small embryos of all seeds of five species grew to a critical length before radicles emerge from the seeds. At 30 days after sowing, the seeds of H. koreana and H. tubiflora germinated to 22.7% and 40.7%, respectively. On the other hand, the seeds of T. rochenbrunianum, T. uchiyamai, and T. coreanum germinated to 12.5%, 3.3%, and 0%, respectively. If embryo growth and germination in seeds are completed in approximately 30 days, the seed are said to have morphological dormancy (MD). However, if the seeds require > 30 days for germination, they are considered to have morphophysiological dormancy (MPD). Thus, the seeds of H. koreana and H. tubiflora had about 78% and 60% MPD, respectively. On the other hand, the seeds of T. rochenbrunianum, T. uchiyamai, amd T. coreanum had about 87%, 96%, and 100% MPD, respectively. There was a different level of dormancy (MD and MPD) within the same seed population examined. Therefore, germination of the seeds was delayed due to the underdeveloped embryos. This result could contribute to determine morphological seed dormancy and germination mechanism in seeds of the Korean Peninsula.