• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.197-204
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• 1989

To evaluate the effect of soil improvement on the chemical properties and corn silage yield, this experiment was carried out in the newly-reclaimed sloped land. Corn (Suwon 19) was cultivated under the six different treatments including integrated improvement plot at Songjeong loam, 20 percent slope, from 1985 to 1987 and various soil chemical properties and silage yield were investigated. pH of topsoil was above 5.0 except for control and phosphate plot, but lime and integrated improvement plots were above 5.0 in subsoil. The contents of organic matter of topsoil were above 2.0% except control and subsoiling plot. Except control, the range of cation exchange capacity was 7.4-7.8 me/100g in topsoil, 7.0-7.7 me/100g in subsoil. Soil bacteria density of root zone was the highest in integrated improvement than the other treatments, and it was higher at the harvesting stage than the heading stage. Mean density of microorganism was $61.3{\times}10^5$ in bacteria, $21.5{\times}10^4$ in fungi and actinomycetes was B/F ratio was 28.5 and B/A ratio was 2.9. Vertical root distribution of total and 10cm depth below was more in the integrated improvement and subsoi ling plot than the other plots. Total nitrogen (T-N) content was higher in integrated improvement plot, and phosphate content of leaves was higher in compost and integrated improvement plot, but stem and grain were not different. Potassium content of the plant was higher in integra ted improvement plot. Correlation between dry matter yield and T-N was more significant than the other elements. And the contents of phosphate, calcium and magnesium were significant at 5%, but potassium was not.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.3
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• pp.153-170
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• 1977

Considering the ways for the possible improvement of soil test for upland crops, various methods for the evaluation of K supplying power and testing of available soil K were reviewed in terms of theoretical principles and practical usefulness of the each method. The review was also made on the characteristics of upland crops in K requirement and on the chemical properties of major korean upland and lowland rice soils in terms of K availability. Following is the few remarks drawn from the review. 1. Quite large number of methods have been known for the evaluation of K supplying power and testing for available soil K. In nature, they can be divided into two categories; capacity-based methods and intensity-based methcds. The capacity-based methods usually measure the exchangeable and some portion of nonexchangeable K, while the intensity-based methods suggest to consider the ractivity ratios of major cations in soil solution and the energy requirement for the replacement of exchangeable soil K into soil solution. 2. As methodology for extraction of interested part of soil K, chemical extraction, electrodialysis and ion exchange methods have been known. Among these, chemical extract ion is favorable because of its simplicity. However, recently suggested Electro-Ultra-Filtration method seems to merit further study for wider use for not only K but also other nutrient availability of soils. 3. The intensity-based methods, although they are more theoretical, because of their complexity, in methods may not be adapted for practical soil tests. 4. The exchangeable K which is rather simple to measure and which well reflects the status of K reserve as nonexchangeable and is immediate pool of water soluble K may be good, if not best, criterion of soil K availability to plant in common soil testing. 5. Because there are evidences that the abundance of available K alone may not be good inclication for availability of K to plant, it is recommendable to interprete the exchangeable K data as percent saturation of exchangeable K to total C. E. C. of soil for the recommend ation of K fertilizer based on soil tests. 6. Some pot and field trial results showed the trends that percent potassium saturation to total C. E. C. better serve as the parameter for K fertilizer recommendation.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.983-991
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• 2012

These days, agricultural products cultivated in facilities occupy the highest percentage of agricultural output price. Specifically cucumbers have been one of the crops that farmers prefer to growing, because their prices were high. However, cucumber crop is sensitive to the soil and environments and it requires the exact crop management. In order to establish cultivation techniques for cucumbers, the current situation of cucumber cultivation was surveyed from ten cucumber farmlands; five farmlands of cucumber cultivation in forcing and five of semi-forcing practicing systems, respectably. The soil conditions were alluvial or valley in soil topology, moderately or poorly drainage in soil drainage classes, coarse loamy in soil texture family. Soil was managed with deep plowing combined with application of basal fertilizers such as compost, rice straw, oil cake, wood chip and chemical fertilizer. The whole soil was prepared in uniformly with rotary. Three major nutrients ($N-P_2O_5-K_2O$)of basal application were 815-464-529 kg $ha^{-1}$ in forcing and 197-135-151 kg $ha^{-1}$ in semi-forcing cultivation. Top dressing of fertilizer was supplied in fertigation system of macro and micro elements in 2~3 day interval with water irrigation. The average yields of cucumbers were $168t\;ha^{-1}$ with 381,000 thousand won $ha^{-1}$ in average gross profit (AGP) in forcing cultivation and $115t\;ha^{-1}$ with 177,000 thousand won $ha^{-1}$ in AGP in semi-forcing cultivation. Cucumber production during the winter season was considered to increase the gross profit because cucumber price tends to stay in high level during this time. The accumulation of soil chemicals like EC, available $P_2O_5$ and exchangeable cations could be controlled by rice straw application. The rice straw application increased soil temperature during the winter season, in exchange of soil air, and in extension of plant roots. In addition, the rice straw application somewhat affected decrease of salts accumulation.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.4
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• pp.358-383
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• 2015

The concept of 'carbon footprint' has been developed as a means of quantifying the specific emissions of the greenhouse gases (GHGs) that cause global warming. Although there are still neither clear definitions of the term nor rules for units or the scope of its estimation, it is broadly accepted that the carbon footprint is the total amount of GHGs, expressed as $CO_2$ equivalents, emitted into the atmosphere directly or indirectly at all processes of the production by an individual or organization. According to the ISO/TS 14067, the carbon footprint of a product is calculated by multiplying the units of activity of processes that emit GHGs by emission factor of the processes, and by summing them up. Based on this, 'carbon labelling' system has been implemented in various ways over the world to provide consumers the opportunities of comparison and choice, and to encourage voluntary activities of producers to reduce GHG emissions. In the agricultural sector, as a judgment basis to help purchaser with ethical consumption, 'low-carbon agricultural and livestock products certification' system is expected to have more utilization value. In this process, the 'cradle to gate' approach (which excludes stages for usage and disposal) is mainly used to set the boundaries of the life cycle assessment for agricultural products. The estimation of carbon footprint for the entire agricultural and forestry sector should take both removals and emissions into account in the "National Greenhouse Gas Inventory Report". The carbon accumulation in the biomass of perennial trees in cropland should be considered also to reduce the total GHG emissions. In order to accomplish this, tower-based flux measurements can be used, which provide a direct quantification of $CO_2$ exchange during the entire life cycle. Carbon footprint information can be combined with other indicators to develop more holistic assessment indicators for sustainable agricultural and forestry ecosystems.

• Analytical Science and Technology
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• v.7 no.2
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• pp.213-224
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• 1994

Several isotopomers of cyclooctanone were prepared by selective deuterium substitution. Intrinsic isotope effects on $^{13}C$ NMR chemical shifts of these isotopomers were investigated systematically at low temperature. These istope effects were discussed in relation to the preferred boat-chair conformation of cyclooctanone. Deuterium isotope effects on NMR chemical shifts have been known for a long time. Especially in a conformationally mobile molecule, isotope perturbation could affect NMR signals through a combination of isotope effects on equilibria and intrinsic effects. The distinction between intrinsic and nonintrinsic effects is quite difficult at ambient temperature due to involvement of both equilibrium and intrinsic isotope effects. However if equilibria between possible conformers of cyclooctanone are slowed down enough on the NMR time scale by lowering temperature, it should be possible to measure intrinsic isotope shifts from the separated signals at low temperature. $^{13}C$ NMR has been successfully utilized in the study on molecular conformation in solution when one deals with stable conformers or molecules were rapid interconversion occurs at ambient temperature. The study of dynamic processes in general requires analysis of spectra at several temperature. Anet et al. did $^1H$ NMR study of cyclooctanone at low temperature to freeze out a stable conformation, but were not able initially to deduce which conformation was stable because of the complexity of alkyl region in the $^1H$ NMR spectrum. They also reported the $^1H$ and $^{13}C$ NMR spectra of the $C_9-C_{16}$ cycloalkanones with changing temperature from $-80^{\circ}C$ to $-170^{\circ}C$, but they did not report a variable temperature $^{13}C$ NMR study of cyclooctanone. For the analysis of the intrinsic isotope effect with relation to cylooctanone conformation, $^{13}C$ NMR spectra are obtained in the present work at low temperatures (up to $-150^{\circ}C$) in order to find the chemical shifts at the temperature at which the dynamic process can be "frozen-out" on the NMR time scale and cyclooctanone can be observed as a stable conformation. Both the ring inversion and pseudorotational processes must be "frozen-out" in order to see separate resonances for all eight carbons in cyclooctanone. In contrast to $^1H$ spectra, slowing down just the ring inversion process has no apparent effects on the $^{13}C$ spectra because exchange of environments within the pairs of methylene carbons can still occur by the pseudorotational process. Several isotopomers of cyclooctanone were prepared by selective deuterium substitution (fig. 1) : complete deuterium labeling at C-2 and C-8 positions gave cyclooctanone-2, 2, 8, $8-D_4$ : complete labeling at C-2 and C-7 positions afforded the 2, 2, 7, $7-D_4$ isotopomer : di-deuteration at C-3 gave the 3, $3-D_2$ isotopomer : mono-deuteration provided cyclooctanone-2-D, 4-D and 5-D isotopomers : and partial deuteration on the C-2 and C-8 position, with a chiral and difunctional case catalyst, gave the trans-2, $8-D_2$ isotopomer. These isotopomer were investigated systematically in relation with cyclooctanone conformation and intrinsic isotope effects on $^{13}C$ NMR chemical shifts at low temperature. The determination of the intrinsic effects could help in the analysis of the more complex effects at higher temperature. For quantitative analysis of intrinsic isotope effects, the $^{13}C$ NMR spectrum has been obtained for a mixture of the labeled and unlabeled compounds because the signal separations are very small.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.4 no.1
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• pp.31-41
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• 1971

The present study was directed to define the degradation pattern of the nucleotides and their related compounds in the muscle of anchovy during drying. Three kinds of samples, fresh, sun dried and boiled-and-dried anchovy, were prepared and the contents of nucleotides and related compounds of samples were determined by ion exchange chromatography. The results obtained are summarized as follows: Almost all of ATP disappeared in both muscle of sun dried and boiled-and-dried anchovy, although the initial content of ATP in fresh muscle was very low ($1.8{\mu}moles/g$, dry basis). But the remainning amount of ADP was considerably high while the other nucleotide almost entirely disappeared. This suggested that the residual ADP is responsible to the 'bound nucleotide' of myofibrils. In general, AMP content was comparatively lower than that of other nucleotides. Among three samples, the boiled-and-dried sample showed relatively higher AMP value than others. The amount of IMP remained in muscle remarkably varied between the boiled-and-dried anchovy and sun dried anchovy, the former's value being sixteen times higher than that of latter. In the contents of inosine and hypoxanthine, the sun dried anchovy marked an exceedingly high value equivalent to 2.7 times of the boiled-and-dried anchovy. In comparison of the ratio of inosine and hypoxanthine, hypoxanthine was accumulating in boiled-and-dried anchovy whereas inosine was in the sun-dried anchovy. Eighty three percent of total nucleotides in the fresh anchovy retained in the boiled-and-dried anchovy and IMP ratio in total nucleotides was $73\%$. On the contrary, the sun dried anchovy showed barely $10\%$ of retention rate and IMP ratio was only $38\%$. Considered from the flavor quality of dried anchovy, so far as concerned IMP content, it may be said that the boiled-and-drying method is more favorable process for dried product of anchovy than the sun-drying method.

• Journal of Korea Technology Innovation Society
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• v.10 no.2
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• pp.284-309
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• 2007

Technology transfer (TT) consortium is an affiliation of two or more public research institutions (PRIs) that participate in a common technology transfer activity or pool their resources together, with the objective of facilitating technology transfer. Based on empirical analysis of five regional TT consortia (2002-2006) operating in Korea, this paper suggests their effectiveness by employing a TT performance index (TTPI) and identifies possible characteristics involved, such as motivations, facilitators, barriers, and challenges. TTPI devised in the paper is a new composite TT performance index to measure how much the TT performance of a PH changed in a designated year compared to a base year. All the performance indicators of TTPI are well-structured based on the unique TT process that is prevalent in Korea. Further, TTPI can bring different size and focus of PRIs to the same scale for comparison by double-normalizing. The paper tests the effectiveness of TT consortium for the escalation of TT performances in member PRIs by highlighting the differences of TTPI's between 2005 and 2001. As a result, the paper found that the escalation of TTPI for member PRIs was greater than that for non-member PRIs. As for the characteristics of TT consortia, their respective factors obtained by TT expert survey were computed with proportion tests of differences (Z tests) to compare two perspectives between intramural and extramural groups. One of key findings is that there is general homogeneity in stakeholder perspectives regarding motivations, facilitators, barriers, and challenges. Some notable responses are as follow; the most probable motivation to join TT consortium is to share or exchange TT competences for enhanced performance. Second, the most probable facilitator is professional capability of consortium-hired personnel. Third, the foremost probable barriers to effective TT consortium are frequent change of consortium director and passive participation of member PRIs. Lastly, both publicizing TT consortia and developing performance metrics are the most important for the improvement of TT consortia. The understanding of the characteristics of TT consortia increases the likelihood of accelerated success, because TT consortia path from formation to termination encompasses many concepts, processes, principles, and factors. Finally, an analysis of the survey data combined with expert interview and observation data led the authors to derive five conditions as being critical to viable TT consortia in Korea at early stage of technology transfer systems. These conditions include policy infrastructure, proactive participation, excellent professionals, personal motivation, and teaming mechanisms. It is expected that the Korean evidence is a starting point to develop and refine the theory of TT consortia and for additional studies in other countries.

• Management & Information Systems Review
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• v.36 no.4
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• pp.117-127
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• 2017

In recent times the size of the world IPO in general has skyrocketed. Specifically, China's financial market development is becoming important as both the size of China's capital market and the number of companies going public are gradually increasing. This has led to a rapid development of venture vapital(VC) institutions in China for the past couple of decades. This study focuses on one of the three markets of China's Shenzhen Stock Exchange-the Growth Enterprise Board((GEB) hereafter, ChiNext). The ChiNext is established in October, 2009 to enable hi-tech or high growth potential technology companies that find it relatively difficult to fulfil the listing requirements of either the Shenzhen Main Board or Small and Medium Size Enterprise Board(SMEB) to go public. This study covers a three-year period(2012/01/-2015/01) and analyze first day initial return of 83 venture capital-backed companies and 53 non-venture capital-backed companies using T-test. Regression analysis is used as to examine the variables affecting IPO's first-day return. The empirical results are four-fold. First, the level of first day return of venture-backed is significantly lower than non venture capital backed support in the Chinese venture capital market. Second, the level of first-day return of listed companies supported by foreign venture capital is significantly higher than that of companies receiving domestic venture capital support. Third, the firms that have a large number of venture capital firms showed a low level of first-day return. Fourth, regression result for the IPO first-day return which is as dependent variable indicates that the venture capital support(VCAP), number of venture capital(VCNum), offering size(Lnsize) and PER all affect have negative effect on the first day initial return. Also, the venture capital type(VCType), turnover ratio and the the firm type(Tech-firms) statistically affect IPO first day return positively. Finally, by shedding more light on the IPO first-day return, this paper provides meaningful information to investors about the Chinese IPO market.

• Journal of the Korean Geotechnical Society
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• v.28 no.5
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• pp.41-54
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• 2012

The weathering process of rocks leads to the reduction of geotechnical bearing capacity. The weathering of granite is frequently used to refer to the degradation of geotechnical property in the design and construction of infra-structure. In this study, the range of values of CIA (chemical index of alteration) and the change of mineral compositions by weathering have been analysed with igneous rock, which covers 45.5% in South Korean territory. Several weathering indices were studied for various rocks found in Korea and significant relationships between different indices were delineated via statistical analysis. The applicability of CIA was found to be the most significant among all weathering indicies. The composition of illite, the secondary weathering residual, generally increases for the felsic rock, and swelling clay material is not included. The weathering of felsic rock will follow a sequential process, starting from bed rock, illite, and chlorite to kaoline. The mafic rock will show weathering process, from bed rock, smectite, and chlorite to kaoline. The intermediate rocks such as andesite and tuff will show similar weathering procedure and the composition of kaoline, chlorite, and smectite tends to increase more than that of illite when the mafic rock is dominated. This means the increase of rock material which has high CEC (cation exchange capacity) during secondary weathering process. However, the characteristics of a specific rock cannot be completely analyzed using merely CIA, since it is exclusively based on chemical composition and corresponding alteration. The CIA can be used to quantify the weathering process in a limited range, and further considerations such as rock composition, strength characteristics will be required to configure the comprehensive weathering impact on any specific region.

• Journal of Aquaculture
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• v.11 no.3
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• pp.391-400
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• 1998

This study was performed to investigate the effects of environmental parameters on the growth of Pacific oyster, Crassostrea gigas at old suspended culturing grounds of Korsung Bay and newly deveoped bottom, culturing grounds of Haenam region located in southern coast of Korea. The Kosung Bay was semiclosed and water exchange occurred through the small mouth and the current speed was very slow as the value of below 0.5kn. Haenam was opened and littoral zone. Current speed of the surroundings of this Bay about to 5.0knand transparency was low with the mean depth of 1.2m by the resuspension of the sediments. Water temperature and salinity regimes were suitable for oysters at those sites, however the mean value of those parameters and seasonal fluctuations was high at Kosung. The mean concentration of dissolved oxygen in survey area was above $5.0mg/\ell$. In Kosung, however, it was decreasing in June and showed the minimum with the concentration of $4.0mg/\ell$ in August at the bottom layer and recovered in September. Eutrophication parameters such as COD were 1.44 mg/l at this location. This mean value was higher than that of the Haenam Bay's $0.96mg/\ell$. The men value of chlorophyll-$\alpha$ at Haenam was two times higher than the other sites. Growth of shell height and meat weight of oysters at Kosung Bay were higher and the fatness was lower compared to thost of Haenam. As a result, absolute growth of oysters was high at Kosung and allometric growth, such as fatness, was good at Haenam. Low water temperature and frequent exposure of oysters to the air during ebb tide may retard the shell growth. On the other hand, relatively high food availability was profitable for the fatness at haenam site.