• International Journal of Industrial Entomology and Biomaterials
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• v.28 no.2
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• pp.58-65
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• 2014

Bumblebees are important pollinators of crops and wildflowers. Bumblebees generally produce one generation per year. One of the key stages for year-round rearing of bumblebees is breaking diapause. To evaluate the effects of a combination method of $CO_2$-narcosis and cold treatment to break the diapause of B. ignitus and B. terrestris queens, we determined whether this method affected their ability to establish a colony after the diapause break. The diapause treatment regimes that were utilized were $CO_2$ ($CO_2$-narcosis), CT-1M (cold treatment at $5^{\circ}C$ for 1 mo), CT-1M-$CO_2$ ($CO_2$-narcosis after cold treatment for 1 mo), CT-2M-$CO_2$ ($CO_2$-narcosis after cold treatment for 2 mo), CT-2M (cold treatment for 2 mo), CT-2.5M-$CO_2$ ($CO_2$-narcosis after cold treatment for 2.5 mo) and CT-2.5M (cold treatment at $5^{\circ}C$ for 2.5 mo). In view of the effects on the colony developmental characteristics of B. ignitus queens, the most favorable diapause treatment was CT-1M-$CO_2$. A combination method of $CO_2$-narcosis and cold temperature treatment yielded better results than that of single $CO_2$-narcosis or cold temperature treatment on the colony development of diapause-broken B. ignitus queens. In the case of B. terrestris queens, we concluded that a combination method of $CO_2$ and cold temperature treatment yielded better results than that of a single cold-temperature (up to 2 mo) treatment. In conclusion, the findings of the present study indicated that the combined application of $CO_2$ and cold temperature was a favorable method for the colony development of diapause-broken B. ignitus and B. terrestris queens compared with only $CO_2$-narcosis or cold temperature treatments. A combination method of $CO_2$ and cold treatment reduced the side effect of $CO_2$-narcosis and shortened the duration of cold treatment by at least 1 mo.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.9
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• pp.389-400
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• 2020

A construction project is a designed product made up of labors, materials, and installations in the project positioned on the ground and may include the underground and ground section, and the section in water or on the water surface. It is a civil, industrial, transport, agricultural and rural development, infrastructure, or some other. A key phase in the life cycle of these construction projects is the implementation when building products are made directly with workers, equipment, materials, and managers. If there is a lack of management experience, information, and problem-solving solutions to tackle the risks faced by contractors, especially foreign ones, will fail in controlling the project's cost. This study was conducted with investigations, discussions, and evaluation of the factors that lead to cost overruns in the construction projects of international contractors in Vietnam. The principal component analysis (PCA) showed that those factors that influence cost overruns these construction projects fall into five general groups, including factors related to (i) the owners, (ii) the foreign contractors, (iii) the subcontractors and suppliers, (iv) state management, and (v) the project itself. Besides, the study proposes solutions to limit cost overruns in construction projects and improve the profitability of international contractors in Vietnam.

• Journal of Electrochemical Science and Technology
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• v.14 no.1
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• pp.1-14
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• 2023

The overuse of pesticides in agricultural sectors exposes people to food contamination. Pesticides are toxic to humans and can have both acute and chronic health effects. To protect food consumers from the adverse effects of pesticides, a rapid monitoring system of the residues is in dire need. Molecularly imprinted polymer (MIP) on a screen-printed electrode (SPE) is a leading and promising electrochemical sensing approach for the detection of several residues including pesticides. Despite the huge development in analytical instrumentation developed for contaminant detection in recent years such as HPLC and GC/MS, these conventional techniques are time-consuming and labor-intensive. Additionally, the imprinted SPE detection system offers a simple portable setup where all electrodes are integrated into a single strip, and a more affordable approach compared to MIP attached to traditional rod electrodes. Recently, numerous reviews have been published on the production and sensing applications of MIPs however, the research field lacks reviews on the use of MIPs on electrochemical sensors utilizing the SPE technology. This paper presents a distinguished overview of the MIP technique used on bare and modified SPEs for the detection of pesticides from four recent publications which are malathion, chlorpyrifos, paraoxon and cyhexatin. Different molecular imprint routes were used to prepare these biomimetic sensors including solution polymerization, thermal polymerization, and electropolymerization. The unique characteristics of each MIP-modified SPE are discussed and the comparison among the findings of the papers is critically reviewed.

• Korean Journal of Organic Agriculture
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• v.9 no.4
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• pp.95-111
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• 2001

To carry out the Integrated Fruit Production(IFP), researches on cover crops as well the Integrated Pest Management(IPM) and the Integrated Nutrition Management(INM) should be very important. These concepts are neither clear nor connective till now. The researches on cover crops in Europe and USA are being kept within the category of IFP. Main researches on fruit trees for sustainable agriculture in Italy are new variety creation, development of growing techniques, pest and disease control, and cover crops management, etc. It is necessary of fruit industry in Korea to maintain good quality and taco-friendly fruit production. For this goal, we need international cooperation with highly developed countries in Europe. In first step, we should enlarge research areas and analyze results obtained to get farmers understood the concept of cover crop growing, Furthermore, we make researches more profoundly on cover crops growing considering tree age, mixing rates among cover crops, seeding and cutting time for cover crops, and so on. Researchers, specialists of agricultural extensions, and farmers should concentrate their opinions and conduct IFP together. The IFP should go on systematically and reach finally to get certificates internationally by the International Organization for Biological and integrated Control of Noxious Animals and Plants(IOBC) to enhance selling and exporting fruits.

• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.124-132
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• 2019

BACKGROUND: Silver grass (Miscanthus sinensis) No. 1 was developed for production of bio-ethanol, and for the purpose the silver grass growing sector was established in Geumgang basin, Iksan, Jeonbuk, in 2011. However, the other application potentials except for using as the bio-energy resources should be considered because of the drop in international oil prices. Therefore, there is the necessity of a scientific basis to use the silver grass instead of rice straw as the organic matter source that is used for improvement of soil quality in the plastic film house. METHODS AND RESULTS: The silver grass was applied at 5, 10, 15 and 20 Mg/ha and tilled before the watermelon was planted in the plastic film-house. The control plot was treated with 10 Mg/ha with rice straw, and watermelons have been cultivated for 3 years(2017~2019). Soil aggregation, soil chemistry, and the growth characteristics were investigated, when the watermelon was harvested every year. Soil aggregation levels at the 2nd and 3rd year of watermelon harvest were similar from the plot applied with the silver grass at 5 Mg/ha and the control plot, and increased in the silver grass treated plots with more than 10 Mg/ha. However, there was no statistically significant difference between the plots. The nitrogen mineralization of silver grass in the control plot tended to be similar to the 5 Mg/ha plot, but the silver grass treated plots with over 10 Mg/ha showed low nitrogen mineralization. Soil EC on harvest stage was proportional to the applied mass of the silver grass, but pH was in inverse with the applied mass. Soil organic matter content, available phosphate, and exchangeable cations increased with the continued use of silver grass. Watermelon weight found to be the best on more than 15 Mg/ha of silver grass, and the sugar content was highest when 10 Mg/ha was treated. CONCLUSION: The use of the silver grass at 10 Mg/ha annually as the organic source was effective in replacing rice straw while growing fruits and vegetables on the plastic film house.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.31-31
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• 2023

Mung bean(Vigna radiata (L.) R. Wilczek var. radiata) is a legume that originated in India. It is the third most cultivated legume in Korea after soybean and adzuki bean. Recently, the use of mung bean seeds and sprouts in trendy foods such as rice noodles and Chinese-style stir-fry is expanding thereby increasing its demand. Subsequently, improvement of mung bean varieties is also being actively conducted. In this study, the important agricultural characteristics of 324 mung bean germplasm were recorded and statistically investigated. Seeds of the mung bean germplasm were cultivated at an experimental field located in the National Agrobiodiversity Center (Jeonju, Korea) and 10 quantitative agricultural traits were investigated. Basic statistics, correlation analysis, and principal component analysis were then performed. The results showed significant variations of the quantitative traits among the germplasms (p < 0.05). The days to flowering, maturity, and growth were in the ranges of 31~80, 22~72, and 57~110 days with means of 45, 47, and 92 days, respectively. The highest frequency (f = 192) was for lodging score with 11~50%, while simultaneous maturity (f = 182) was below 50%. Other quantitative traits related to yield including the number of seeds per pod (CV = 10.9%), number of pods per plant (CV = 41.2%), and one-hundred seeds weight (CV = 36.6%) also showed significant variations. Correlation analysis showed positive correlations between the days to maturity and one-hundred seeds weight (r = 0.41) and the days to growth and simultaneous maturity (r = 0.39). In contrast, one-hundred seeds weight was negatively correlated to the number of pods per plant (r = -0.41) and the days to flowering (r = -0.29). Similarly, the days to growth and the number of pods per plant had a negative association with each other (r = -0.29). The principal component analysis revealed the number of days to maturity as the most influential variable along the first principal component (23.7%). In general, this study revealed wide variations in quantitative traits among the studied mung bean germplasm, which could provide several options for cultivar development.

• Journal of Industrial Convergence
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• v.17 no.2
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• pp.9-14
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• 2019

This study was carried out to investigate how the basic plan of the Saemangeum development project that has been developed by the government since 1991 has been changed and to present a new development strategy by analyzing the future value and tourism resource value of Saemangeum development. The research methodology is based on the in - depth analysis methodology of the time series research materials and press releases published by the Saemangeum Development Administration, which oversees the development of Saemangeum. The government announced a plan to significantly reduce agricultural land and increase the proportion of non-agricultural land to 70% in order to create a multifunctional complex. After that, the government revised the basic plan of Saemangeum in 2014 and changed the plan to tailor the investment demand in order to cultivate investment demand, and introduced the special economic cooperation system for global economic cooperation. Therefore, the purpose of this paper is to analyze the process of Saemangeum development to date and to evaluate the value of Saemangeum development as a tourism resource, centered on the Master Plan of the Saemangeum Development Project changed by the government. Based on the results of this analysis, I would like to present the vision of Saemangeum tourism development considering Saemangeum 's environment and characteristics of the surrounding scenery by referring to trends and similar cases of international tourism.

• Korean Journal of Environmental Agriculture
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• v.38 no.1
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• pp.23-33
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• 2019

BACKGROUND: The golden apple snail(GAS, Pomacea canaliculata Lamarck) is an invasive freshwater snail. It has occurred 34 years since the introduction of the GAS to the Korea. The GASs have been used recently for weed control in wet rice cultivation. The GASs'adaptability to the environment of GAS has been improved and the GASs devour the young stage of the crops as well as weeds. METHODS AND RESULTS: We surveyed the survival area of the snails throughout the country during the winter seasons from 2000 to 2017 and crop damage due to GASs in 2017. Local maximum, minimum, and average air temperatures were monitored daily. The surveyed regions for the survival of the GASs in winters were Gangjin, Goheung, Shinan, Haenam, Gimhae, Haman, Busan, Jeju, and Seogwipo. The survival durations at low temperatures were 12 hours at $-5^{\circ}C$, 1 day at $-3^{\circ}C$, 2 days at $-1^{\circ}C$, 10 days at $0^{\circ}C$, and over 30 days at $3^{\circ}C$. The eggs of GASs were not able to overwinter. The overwintering condition of the GAS needed a water depth of 10-20 cm with well formed mud. Crop damages caused by the overwintering GASs occurred in rice and water dropwort. CONCLUSION: The overwintering GAS was first identified in Haenam, South Korea 2000 after introduction of the GAS. The overwintering area of GAS expanded to the mid-southern parts of Korea. We propose that it has not yet become a pest to rice or any other crop.

• Journal of Distribution Science
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• v.8 no.3
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• pp.17-26
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• 2010

Recently concerns have been raised due to the unbalanced supply of crops: the price of crops has been unstable and at one point the price went up so high that the word Agflation(agriculture+ inflation) was coined. Korea, in particular, is a small-sized country and needs to secure the stable supply of crops by investing in the produce importation at a national level. Investment in foreign produce importation is becoming more important as a measure for sufficient supply of crops, limited supply of domestic crops, weakened farming conditions worldwide, as well as recent changes in the use of crops due to the development of bio-fuels, influence of carbon emission on crops, the price increase in crops, and influx of foreign hot money. However, there are many problems with investing in foreign produce importation: lack of support from the government; lack of farming information and technology; difficulty in securing the capital; no immediate pay-off from the investment and insufficient management. Although foreign produce is originally more price-competitive than domestic produce, it loses its competiveness in the process of importation (due to high tariffs) and poor distribution system, which makes it difficult to sell in Korea. Therefore, investment in foreign produce importation is being questioned for feasibility; to make it possible, foreign produce must maintain the price-competitiveness. Especially, harvest of agricultural products depends on natural and geographical conditions of each country and those products have indigenous properties, so distribution system according to import and export of agricultural products should be treated more carefully than that of other industries. Distribution costs are differentiated into each item and include cost of sorting and wrapping, cost of wrapping materials, cost of domestic transport, cost of international transport and cost of clearing customs for import and export. So transporting and storing agricultural products generates considerable costs compared with other products. Also, due to upgrade of dietary life, needs for stability, taste and visible quality toward food including agricultural products are being raised and wrong way of storage causes decomposition of food and loss of freshness, making the storage more difficult than that in room temperature, so storage and transport in distribution of agricultural products needs specialty. In addition, because lack of specialty in distribution and circulation such as storage and wrapping does not solve limit factors in distance, the distribution and circulation has been limited to a form of import and export within short-distant region. Therefore, need for distribution out-sourcing which can satisfy specialty in managing distribution and circulation and it is needed to establish more effective distribution system. However, existing distribution system of agricultural products is exposed to various problems including problems in distribution channel, making distribution and strategy for distribution and those problems are as follows. First, in case of investment in overseas agricultural industry, stable supply of the products is difficult because areas of production are dispersed widely and influenced by outer factors due to including overseas distribution channels. Also, at the aspect of quality, standardization of products is difficult, distribution system is quite complicated and unreasonable due to long distribution channels according to international trade and financial and institutional support is not enough. Especially, there are quite a lot of ineffective factors including multi level distribution process, dramatic gap between production cost and customer's cost, lack of physical distribution facilities and difficulties in storage and transport due to lack of wrapping containers. Besides, because import and export of agricultural products has been manages under the company's own distribution according to transaction contract between manufacturers and exporting company, efficiency is low due to excessive investment in fixed costs and lack of specialty in dealing with agricultural products causes fall of value of products, showing the limit to lose price-competitiveness. Especially, because lack of specialty in distribution and circulation such as storage and wrapping does not solve limit factors in distance, the distribution and circulation has been limited to a form of import and export within short-distant region. Therefore, need for distribution out-sourcing which can satisfy specialty in managing distribution and circulation and it is needed to establish more effective distribution system. Second, among tangible and intangible services which promote the efficiency of the whole distribution, a function building distribution environment which includes distribution information, system for standard and inspection, distribution finance, system for diversification of risks, education and training, distribution administration and tax system is wanted. In general, such a function building distribution environment is difficult to be changed and supplement innovatively because its effect compared with investment does not appear immediately despite of its necessity. Especially, in case of distribution of agricultural products, as a function of collecting and distributing is performed individually through various channels, the importance of distribution information and standardization is getting more focus due to the problem of repetition of work and lack of specialty. Also, efficient management of distribution is quite difficult due to lack of professionals in distribution, so support to professional education is needed. Third, though effort to keep self-sufficiency ratio of staple food, rice is regarded as important at the government level, level of dependency on overseas of others crops is high. Therefore, plan for stable securing food resources aside from staple food is also necessary. Especially, governmental organizations of agricultural products distribution in Korea are production-centered and have unreasonable structure whose function at the aspect of distribution and consumption is quite insufficient. And development of new distribution channels which can deal with changes in distribution environment and they do not achieve actual results of strategy for distribution due to non-positive strategy for price distribution. That is, it implies the possibility that base for supply will become vulnerable because it does not mediate appropriate interests on total distribution channels such as manufacturers, wholesale dealers and vendors by emphasizing consumer protection excessively in the distribution of agricultural products. Therefore, this study examined fundamental concept and actual situation for our investment to overseas agriculture, drew necessities, considerations, problems, etc. of overseas agricultural investment and suggested improvements at the level of distribution for price competitiveness of agricultural products cultivated in overseas under five aspects; government's indirect support, distribution's modernization and distribution information function's strengthening, government's political support for distribution facility, transportation route, load and unloading works' improvement, price competitiveness' securing, professional manpower's cultivation by education and training, etc. Here are some suggestions for foreign produce importation. First, the government should conduct a survey on the current distribution channels and analyze the situation to establish a measure for long-term development plans. By providing each agricultural area with a guideline for planning appropriate production of crops, the government can help farmers be ready for importation, and prevent them from producing same crops all at the same time. Government can sign an MOU with the foreign government and promote the importation so that the development of agricultural resources can be stable and steady. Second, the government can establish a strategy for an effective distribution system by providing farmers and agriculture-related workers with the distribution information such as price, production, demand, market structure and location, feature of each crop, and etc. In order for such distribution system to become feasible, the government needs to reconstruct the current distribution system, designate a public organization for providing distribution information and set the criteria for level of produce quality, trade units, and package units. Third, the government should provide financial support and a policy to seek an efficient distribution channel for foreign produce to be delivered fresh: the government should expand distribution facilities (for selecting, packaging, storing, and processing) and transportation vehicles while modernizing old facilities. There should be another policy to improve the efficiency of unloading, and to lower the cost of distribution. Fourth, it is necessary to enact a new law covering exceptional cases for importing produce in order to maintain the price competitiveness; currently the high tariffs is keeping the imported produce from being distributed domestically. However, the new adjustment should be made carefully within the WTO regulations since it can create a problem from giving preferential tariffs. The government can also simplify the distribution channels in order to reduce the cost in the distribution process. Fifth, the government should educate distributors to raise the efficiency and to modernize the distribution system. It is necessary to develop human resources by educating people regarding the foreign agricultural environment, the produce quality, management skills, and by introducing some successful cases in advanced countries.

• Journal of the Korean Society of International Agriculture
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• v.30 no.4
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• pp.357-369
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• 2018

The Korean common bean (Phaseolus vulgaris L.) has been receiving increased attention as a functional food. The objective of this study was to reveal the phytochemicals genetic variation and antioxidant activity of 209 Korean common bean landraces. Antioxidant activity was evaluated with the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate), ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), ferric reducing antioxidant power (FRAP), and superoxide dismutase (SOD) assay. Antioxidant activities among common bean accessions showed wide variation. Four flavonoids (kaempferol, myricetin, quercetin, and naringenin) of the 209 Korean common bean landraces were measured using HPLC. Among them, kaempferol had the highest phytochemicals compared to the other three flavonoids. Using the relative antioxidant capacity index (RACI), it was found out that the IT104587 had the highest antioxidant activity. Meanwhile, in clustering analysis, the Korean common bean landraces were classified into three clusters. Among them, cluster II contained 64 landraces with higher antioxidant activities and phytochemicals than the other clusters, except DPPH. The results could provide information on the valuable Korean common bean landraces for the development of new common bean varieties.