• Korean Journal of Heritage: History & Science
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• v.50 no.4
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• pp.122-147
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• 2017

The Jungsandong sites are distributed across quartz and mica schist formations in Precambrian, and weathering layers include large amounts of non-plastic minerals such as mica, quartz, felspar, amphibole, chlorite and so on, which form the ground of the site. Neolithic pottery from Jungsandong exhibits various brown colors, and black core is developed along the inner part for some samples, and sharp comb-pattern and hand pressure marks can be observed. Their non-plastic particles have various composition, size distribution, sorting and roundness, so they are classified into four types by their characteristic mineral compositions. I-type (feldspar pottery) is including feldspar as the pain component or mica and quartz. II-type (mica pottery) is the combination of chloritized mica, talc, tremolite and diopside. III-type (talc pottery) is with a very small amount of quartz and mica. IV-type (asbestos pottery) is containing tremolite and a very small amount of talc. The inner and outer colors of Jungsandong pottery are somewhat heterogeneous. I-type pottery group shows differences in red and yellow degree, depending on the content of feldspar, and is similar to III-type pottery. II-type is similar to IV-type, because its red degree is somewhat high. The soil of the site is higher in red and yellow degree than pottery from it. The magnetic susceptibility has very wide range of 0.088 to 7.360(${\times}10^{-3}$ SI unit), but is differentiated according to minerals, main components in each type. The ranges of bulk density and absorption ratio of pottery seem to be 1.6 to 1.7 and 13.1 to 26.0%, respectively. Each type of pottery shows distinct section difference, as porosity and absorption ratio increase in the order as follows: I-type (organic matter fixed sample) < III-type and IV-type < I-type < II-type (including IV-type of IJP-15). The reason is that differences in physical property occur according to kind and size of non-plastic particles. Although Jungsandong pottery consists of mixtures of various materials, the site pottery has a geological condition on which all mineral composition of Jungsandong pottery can be provided. There, it is thought that raw materials can be supplied from weathered zone of quartz and mica schist, around the site. However, different constituent minerals, size and rock fragments are shown, suggesting the possibility that there can be more raw material pits. Thus, it is estimated that there may be difference in clay and weathering degree.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.1
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• pp.45-52
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• 2019

This experiment was carried out to study the change of productivity and feed value in different types of hilly pasture. The pasture utilized in the experiment was placed on the experimental farm of Pyeongchang Campus of Seoul National University. Forage production type(FP; Orchardgrass 18 + Tall Fescue 12 + Timothy 5 + White clover 5 kg/ha) and Public farm type(PF: Orchardgrass 12 + Tall Fescue 18 + Timothy 5 + White clover 5 kg/ha) pasture were established in September 3, 2014 and utilized (cutting or grazing) four times every year. Growth characteristics, yield and forage quality were investigated for two years. Plant height of grasses was the highest in the $1^{st}$ cutting and legumes was in the $2^{nd}$ cutting. Dry matter (DM) content was highest at every the $1^{st}$ cut grasses significantly lower at the $2^{nd}$ harvest (p<0.05). However, there was no significant difference in the $2^{nd}$, $3^{rd}$ and $4^{th}$ harvest in 2016. In the botanical composition change, the portion of legume was gradually increased after pasture establishment and the ratio of weed and bare land was higher at $2^{nd}$ and $3^{rd}$ cutting, but it was decreased at $4^{th}$ harvest. There was no significant difference in 2016 of fresh yield between two farm types (p>0.05). The yield of dry matter showed similar trend of fresh yield and forage production type was higher than that of public farm type (p<0.05). The forage intake by livestock was 1,452 kg/ha in 2015 and 1,743 kg/ha in 2016. Pasture utilization ratio of public farm type pasture was highest in the $3^{rd}$ grazing time. Forage quality of pasture in relation to management type had not significant difference, but there was difference in harvest times. Crude protein (CP) was the lowest in the $1^{st}$ harvest and total digestible nutrient (TDN) was highest in the $1^{st}$ harvest and lowest in the $4^{th}$ harvest. Based on the above results, it is found that the establishment of pasture suitable for farm's situation is important for set up of Korean model of hilly pasture. Although the forage production type is superior on forage productivity, it is recommended that the results will be provided as basic data for management of public farm type in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.1
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• pp.40-47
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• 2019

This study was conducted to investigate the effect of planting density on plant growth, yield, and quality in the sweet sorghum cultivar 'Chorong' (Sorghum bicolor (L.) Moench). Plants were cultivated at densities of 16.7, 11.1, 8.3, 6.7, and $5.6plants{\cdot}m^{-2}$. Factors related to yield and yield components were analyzed using correlation and multivariate analyses. There was no significant difference among plant densities in stem length from 20 to 110 days after sowing. But the stem diameter was thin, and a decrease in number of tillers occurred more rapidly as planting density increased. At harvest, juice and sugar yield were higher at densities of 16.7 (42.9, $4.16Mg{\cdot}ha^{-1}$, respectively) and 11.1 (37.1, $3.73Mg{\cdot}ha^{-1}$) $plants{\cdot}m^{-2}$ than at 8.3 (30.5, $2.96Mg{\cdot}ha^{-1}$), 6.7 (26.6, $2.41Mg{\cdot}ha^{-1}$), and 5.6 (24.7, $2.22Mg{\cdot}ha^{-1}$) $plants{\cdot}m^{-2}$. The soluble solids and total sugar contents were not different among treatments, but relatively high values were observed at the density of 11.1 and $8.3plants{\cdot}m^{-2}$. As plant density was increased from 5.6 to $11.1plants{\cdot}m^{-2}$, the lodging index (1 = no, 9 = lodging) increased rapidly from 2.00 to 6.33. To determine the optimal planting density, the number of typhoons and topographical characteristics should be considered. Correlation and principal components analyses revealed that plant density exhibited a positive relationship with fresh stem yield ($r=0.62^{**}$), dry stem yield ($r=0.58^{**}$), juice ($r=0.63^{**}$), and sugar yield ($r=0.66^{**}$), but a negative with stem diameter ($r=-0.65^{**}$). The yield factors were not statistically related to stem height, diameter, and number of nodes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.4
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• pp.322-330
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• 2018

The correlation between the nutritional composition of soybeans and whole soymilk palatability was investigated using nine soybean cultivars (Teagwangkong, Daewonkong, Saedanback, Jinpung, Daechan, Miso, Cheongmiin, Cheongja 3, and Socheongja). Physicochemical analysis of soybeans, showed that the protein and lipid contents were 37.7-46.0 and 15.2-20.9%, respectively. Unsaturated fatty acids were 81.1-84.8% of total fatty acids, of which linoleic acids was 49.7-56.8%. Total tocopherol was $243.5-361.3{\mu}g/g$ of extract, of which ${\gamma}$-tocopherol was $67.14-86.49{\mu}g/g$. Total isoflavone contents varied within cultivars from $495.4-1,443.8{\mu}g/g$ of extract. Daidzin and genistin were 252.1-556.0 and $241.8-730.7{\mu}g/g$, respectively, which were major isoflavones in soybeans. For the sensory evaluation, whole soymilk was made from nine soybean cultivars and 20 panels investigate its palatability. The Daechan cultivar had the highest (9.1), and Cheongmiin the lowest (5.6), overall palatability score. Interestingly, sensory results were strongly correlated with linoleic acid (0.746) and stearic acid (-0.716) content. In summary, the fatty acid composition of soybeans is the key factor in determining the palatability of whole soymilk. This study could be applied to determine the suitability of cultivars for soybean products, including whole soymilk.

• Journal of Dairy Science and Biotechnology
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• v.37 no.2
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• pp.115-128
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• 2019

Lactic acid bacteria obtained from traditional Kimchi were selected on the basis of their caseinolytic activity and lactose usability and examined for availability as a starter in probiotic activity. Thirty-two strains were selected as lactic acid producing bacteria in BCP agar, and two strains (KC23 and KF26) with more than 90% resistance for both acid and bile salts were selected. The two strains were identified as L. plantarum (KC23) and L. paracasei (KF26) by API 50 CHL system and 16S rRNA sequence analysis. L. plantarum (KC23) was finally selected based on its biochemical characteristics for lactose and raffinose usability. Free tyrosine content increased rapidly in 10% skimmed milk medium, from $24.1{\mu}g/mL$ after 8 h to $43.9{\mu}g/mL$ after 16 h. Additionally, the caseinolytic clear zone of 12 mm of L. plantarum (KC23) was greater than the 9 mm zone of commercial L. acidophilus CSLA. The bacterium exhibited mesophilic growth and yielded $8.9{\times}10^8CFU/mL$ when incubated at $37^{\circ}C$ for 12 h at pH 4.25. Moreover, L. plantarum KC23 exhibited antibacterial activity as it formed a clear zone of 8-13 mm for the 5 pathogens. Adherent activity was 2.23 fold higher than that of LGG. The acidity of 10% skimmed milk fermented for 12 h was 0.74%.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.3
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• pp.49-61
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• 2019

Swine manure has been recognized as a organic sources for composting and many research was conducted to efficiently utilize and treat. This study was to evaluate a feasibility for producing swine manure compost under various treatment with mixture of swine manure and saw dust. Treatments were designed as follows; non aerated composting pile(REF), aerated composting pile of $100L/m^3$(EXP1), and aerated composting pile of $150L/m^3$(EXP2). The total days of fermentation were 28 days and each samples were collected at every 7 days from starting of composting. Temperature sensors were installed under 30~40cm from the surface of composting pile. Inner temperature in composting piles of EXP1 and EXP2 was rapidly increased to $67{\sim}75^{\circ}C$ within 1~2 days. The elevated temperatures found during the thermophilic phase are essential for rapid degradation of organic materials. While swine manure composted, moisture content, total nitrogen, EC of EXP1, EXP2 in sample at 28 days were lower than those of REF. But, pH and organic matter of EXP1, EXP2 in sample at 28 days were higher than those of REF. After finishing fermentation experiment, maturity was evaluated with germination test. Calculated germination index(GI) at REF, EXP1 and EXP2 were 23.49, 68.50 and 51.81, respectively. The values of germination index were higher at EXP1 and EXP2 which is aerated composting piles than REF which is non aerated composting pile. According to the results, composting process by aerated static pile compost had significant effect on the reduction of required period for composting. Supplying adequate amount of air to compost swine manure will greatly reduce composting period.

• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.166-172
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• 2019

BACKGROUND: Increase in the ratio of small berries in blueberry production decreases the farmers' profits due to weakening market competitiveness and lowering harvest efficiency. One of the reasons for increased small berries is over fruit-load. For improving productivity and competitiveness of blueberry in Korea, hand-thinning can be applied to increase fruit quality before the developing adequate chemical thinning methods. This study was conducted to investigate the proper timing and methods for floral buds thinning in rabbiteye blueberry. METHODS AND RESULTS: Eight years old bushes of rabbiteye bluberries 'Brightwell' as a primary cultivar and 'Powderblue' as a pollinizer were used for this study. Fruit size distribution by leaf-to-fruit ratio was investigated by counting the number of leaves and fruits in canes of 127 'Brightwell' plants whose fruit set varied. Fifty percent of flowers/floral buds were removed in four different floral buds stages such as bud swell, late pink bud, full bloom, and petal fall, and the consumed time for thinning and fruit characteristics were recorded to investigate the effect and proper timing of floral buds thinning. Fruit weight and soluble solids content tended to increase in proportion to leaf-to-fruit ratio and the production of the number of fruits less than 13 mm in diameter decreased when leaf-to-fruit ratio was more than 2.5. Manual floral buds thinning by hands was fastest in full bloom stage and slowest in bud swelling stage. In all cultivars, fruit size was significantly smaller in non-thinning treatment than thinning, and there was, however, no significant difference in total fruit yield. The number of fruits less than 13 mm in diameter increased in both cultivars as floral buds thinning was delayed. Consumed time for picking 90% berries out of total berries per bush was shortest in full bloom stage thinning in 'Brightwell' and bud swelling, full bloom thinning in 'Powderblue'. These were 25 and 20 days faster than no thinning, respectively. CONCLUSION: Although the effect of floral buds thinning varied depending on the cultivars, our results confirmed that floral buds thinning was effective for the early intensive harvesting and the increase of the large fruit ratio and the harvesting productivity. Also, in order to increase thinning efficiency, it is recommended to remove the flower buds before the full bloom stage.

• The Korean Journal of Archival Studies
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• no.30
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• pp.3-55
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• 2011

Recently, a topic of Archival Science can be said 'paradigm shift'. Therefore, this study aims to establish a relationship between oral record and Archival Science through concept of the archiving 'social memory' related to paradigm shift of Archival Science. In addition, an active role theory by an archivist as main agent of archival oral record management reflecting the characteristics of oral record based on this will be supported. Especially, even if it has already been handled through previous studies, it will be focused on drawing new meaning by applying creative perspective. Main content of this study is as follows. Firstly, discussion will be progressed by establishing the concept of the archiving 'social memory'. This is related to the topic of 'paradigm shift' in the Archival Science. Despite that active research has been conducted among mainly archival researchers overseas, it has not been handled yet in Korea. Therefore, this study aims to determine to organize this part as detail purpose. Secondly, the point will be progressed with a special focus on collecting and planning stages among the stages of records management. A viewpoint of the Archival Science should start from the stage of collecting and planning the previous record of production point of time, and then should be reflected for acknowledging the subsequent stages. Therefore, collecting and planning are the most important, and this is closely connected with a characteristic of oral record which production means collecting. Thirdly, the concept of 'oral record' is established with the viewpoint of the Archival Science. The various documents have been producted through oral interview has been known to many oral history researchers as 'oral source'. It aims to conceptualize them as 'oral record' with the viewpoint of the Archival Science. Fourthly, it is an establishment of meaning why oral history should be handled in the Archival Science. It is necessary to rationalize the purpose and its appropriateness handling oral history in the Archival Science. It should clarify the reason why oral history is important in the Archival Science and what it means. This will help examine the meaning of the recording of 'oral record.' A characteristic of the oral record can be effectively revealed through the recording, and ultimately, it aims to be able to shed new light on the value of oral history and oral record. Finally, it defines the role of archivist in oral history. A point that archivist in oral history is not just an assistant who organizes and preserves oral records collected by researchers will be emphasized and persuaded. In this study, oral history study in the Archival Science which has obtained appropriateness by the theoretical discussion as above should be conducted in a connection with other studies without occupying oral history by the Archival Science and in a direction of the leap of Korean oral history study. If this is possible, it will contribute to development of the Archival Science and of study area expansion, enhancement of the role and potential of archivist, at the same time, eventually it will positively influence on oral history study.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.490-496
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• 2018

"Samkwang1," a japonica rice variety, was developed as a cross between "Samkwang" and F1 of Suwon152 (IT008283), which has a medium maturing and lodging resistance and Samkwang (IT284608), a high quality variety with bacterial blight resistance and mid-late maturing property by the rice breeding team at NICS in 2015. The heading date of "Samkwang1" was August 8 in the middle plain area, which was 2 days early than that of "Hwaseong." "Samkwang1" had a culm length of 77 cm, which was 7 cm shorter than that of "Hwaseong," and it had 128 spikelets per panicle. The viviparous germination rate of "Samkwang1" was 2.1%. "Samkwang1" showed resistance to blast, bacterial blight (K1, K2, and K3 race) and stripe virus, but was susceptible to the K3a race of bacterial blight, dwarf and black streak dwarf viruses, and plant hoppers. The milled rice of this variety exhibits translucent and medium short grains. The cooked rice grains of "Samkwang1" have an excellent palatability index (0.35) and lower protein content (6.2%) than that of "Hwaseong." The characteristics related to grain milling were better than those of "Hwaseong," especially the head rice milling recovery ratio and head rice ratio (94.2%). "Samkwang1" showed 5.62 MT/ha of milled rice productivity at 11 sites under ordinary cultivation conditions (Registration No. 6798).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.2
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• pp.146-154
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• 2021

This study was conducted to determine the degree of reduction in the yield of sweetpotato subjected to different shading treatments according to the growing season of the typical viscous sweetpotato 'Hogammi' and the powdery sweetpotato 'Jinyulmi'. Shading was provided using commercially available shading nets (55% and 75% shading level), and the treatments were applied at the following stages of storage root growth: SFS: the storage root formation stage (planting-50^th day), SSS: the storage root swelling stage (50-90^th day), and SAS: the storage root actively swelling Stage (90-120^th day). The growth characteristics according to shading treatments during each growth period, the number of tubers obtained at harvest, and sugar contents were investigated. For both assessed cultivars, there was no significant difference between the control group and the 55% shading treated group with respect to the maximum quantum yield (Fv/Fm) of photosystem II under different shading treatments, whereas the 75% shading group showed slightly higher values than the control group. In both cultivars, the contents of chlorophyll a and b tended to increase in plants subjected to shading treatments compared with the control plants, particularly that of chlorophyll b. Compared with the control group, the chlorophyll b content of 'Hogammi' subjected to 55% and 75% shading increased by 47% and 41%, respectively, whereas that of 'Jinyulmi' increased by 39% and 34%, respectively. We also detected reductions in the dry weights of the above- and belowground parts of the two varieties in response to shading compared with the control, with the reduction in the dry weight of belowground parts being significant. Furthermore, in both varieties, the T/R rate tended to increase in response to shading treatment. Owing to the lack of sunlight, both cultivars tended to suppress the formation and enlargement of tuber roots. Consequently, post-harvest yield analysis revealed that under shading treatments, both cultivars were characterized by poor tuber root growth according to growing season, with the yield of 'Hogammi' showing a greater reduction compared with that of 'Jinyulmi'. In addition, we found that the higher shading level also significantly reduced yields. Compared with the storage root formation and storage root actively swelling stages, shading treatments during the storage root swelling stage significantly affected yield reduction in both varieties.