• Economic and Environmental Geology
• /
• 제54권5호
• /
• pp.535-547
• /
• 2021

Aggregate is an essential construction material, and the demand is increasing every year. Aggregate has different properties in each region, and it is difficult to supply it over long distances due to its quantity and weight. For the stabilization of aggregate supply and demand, regional aggregate resource surveys have been conducted since 1993 in Korea. In this study, an aggregate resource survey was conducted in Goyang City to understand the characteristics of aggregate distribution as part of the annual regional aggregate resource survey in 2020. Goyang City has a high mountainous area to the east, and the southwestern part shows a topography where a wide flatland develops. It has 18 small streams originated from the eastern mountainuos area and 1 large stream Han River. The drilling data shows that thickness of the Quaternary deposits tend to deepen toward the south. The aggregate reserves are relatively abundant, the depth of the aggregates are relatively deep. Changes in the depth of the Quaternary deposits and the amount of aggregate in Goyang are seems to be closely related to the activities of the Han River rather than the sedimentation characteristics from the upstream to the downstream of the small streams. This characteristics show a similar tendency to the distribution of aggregates in adjacent regions to the west coast in Korea. Therefore, the regions that close to west coast have a high probability of aggregate reserves around relatively large-scale streams flowing into the west coast.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• 제66권3호
• /
• pp.210-219
• /
• 2021

In recent years, air temperature has been increasing rapidly compared to the 1980s because of global warming. This increase in temperature reduces the yield and quality of rice; therefore, measures are needed to prevent such effects and ensure food security. The early maturing type (EMT) of rice is mainly cultivated in the central northern mid-mountainous area (CNMA). This study was conducted to shift the transplanting date of EMT and to examine the adaptability of the mid-maturing type (MMT) or mid-late maturing type (MLMT) in the Jecheon region of the CNMA to address global warming. The air temperature increased by 0.7-0.9℃ in the 2010s, compared to that in the 1980s, and was similar to other decades during the ripening period. Over the past 35 years, considering rice quality, the heading date of the Odae variety has arrived sooner by approximately 10 days, the ripened grain ratio has increased by more than 10%, and the thousand grain weight; however, the mean temperature at 40 days after heading has increased by more than 2℃. The late marginal heading date in the Jecheon region was determined as August 11 based on the accumulated temperature of 880℃ and August 15 based on 840℃ for 40 days after heading. According to different transplanting dates, milled rice yield per 10 a was the highest at 567 kg with June 10 in EMT, 595 kg with June 10 in MMT, and 572 kg with May 30 in MLMT. Considering the late marginal heading date, rice yield, and quality, the optimum transplanting date was June 15 in EMT, June 5 in MMT, and May 30 in MLMT in the Jecheon region of CNMA. Owing to global warming, MMT and MLMT are expected to be reliably cultivated in the CNMA.

• Journal of the Korean Applied Science and Technology
• /
• 제38권4호
• /
• pp.951-962
• /
• 2021

The purpose of this study was to analyze the effects of smart machine circulation exercise on body composition, lung function, blood lipid and insulin resistance in obesity middle-aged women among 40-60 years by dividing them into a smart machine circulation exercise group(n=8), and control group(n=6). The smart machine circulation exercise program included 55-minutes sessions thrice each week at the following intensities: The strength of aerobic exercise is applied to smart machines by linking the smart machine with the POLAR T31; the 1-4 week is 40-50%HRR, 5-8 week is 50-60%HRR, and 9-10 week is 60-70%HRR. The strength of the resistance exercise was tested using a smart machine based on the constant velocity motion, and then, using the 1-RM data value, applied 40% 1-RM for 1-4 weeks, 60% 1-RM for 5-8 weeks, and 80% 1-RM for 9-10 week. As a results, body composition indicated that weight, BMI, %BF, WHR had a significant interaction effect. Lung function indicated that FVC levels significantly changes in the exercise group and the between groups difference in changes at 10week was significant. Also, FVC and FEV₁ significantly showed interaction effect. TC, TG and HDL-C levels significantly changes in smart machine circulation exercise group and the between-group difference in changes after 10 weeks was significant. TC, TG and HDL-C significantly showed interaction effect. Insulin resistance demonstrated that Insulin, Glucose and HOMA-IR levels significantly showed difference over 10 weeks between group. Therefore, the 10 weeks smart machine circulation exercise positively effects on the body composition, lung function, blood lipids, and insulin resistance in obesity middle-aged women and this smart machine circulation exercise can improve their obesity and prevent obesity.

• Journal of Bio-Environment Control
• /
• 제30권4호
• /
• pp.263-270
• /
• 2021

This experiment was carried out to determine the effect of CaCl₂ foliar spraying on the inhibition of blossom-end rot (BER) in hot summer paprika (Capsicum annum L. 'Special') cultivation. The effect of CaCl₂ application was examined by the foliar application based on different fruit size, frequency, and spraying time. Also, it was investigated the occurrence and alleviation effect of BER symptom. Foliar application of CaCl₂ (Ca 0.4%) was conducted by treating a fruit and leaf at 4 to 9 nodes above the crown flowers of each plant with 350 mL per week from June 3 to July 1. When the CaCl₂ was sprayed at 7-day intervals for 4 weeks, the Ca content was the lowest in the fruit harvested with BER symptom in 11 to 20 mm of fruit width (FW). Four different regions in both BER symptom and normal fruits showed significant differences of Ca content, the highest was in pedicel, followed by stem-end, middle, and blossom-end. The Ca content increased sharply in normal paprika with 31-40 mm FW, in which Ca content was 78% higher than that of BER. Ca content in the middle and blossom-end of paprika over 21 mm in FW ranged 19.8% to 28.8% in normal fruits and 15.7% to 18.5% in BER, respectively. The incidence of BER increased rapidly by more than 60% in fruits with 31-40 mm FW. While there was no difference in fruit weight among the FW treatment, marketable yield rate was highest in the 21-30 mm FW, and the sugar content was high in the 11-30mm FW. When CaCl₂ was applied three times for 7 days to a paprika having a 21- 30 mm FW, the cell wall-bound (CWB) Ca content was the highest and the rate of BER was lowest with 6.3%. After 10 days of CaCl₂ foliar spray treatment, the CWB Ca content of paprika increased by 2.9 to 3.5 times compared to the control in all treatments. At 7 days after the CaCl₂ foliar spraying once a day at varying spraying time, the leaf burn observed from 9:30 a.m. to 17:00 p.m. and the proline content increased as the spraying time was delayed. Therefore, the CaCl₂ foliar spraying method for reducing of BER occurrence during paprika summer cultivation seems to be appropriate to spray 2-3 times at intervals of 3 days and before 8 a.m. at the time when the FW is 21-30 mm.

• Korean Journal of Ichthyology
• /
• 제32권4호
• /
• pp.210-221
• /
• 2020

Since the introduction of Israeli carp into Korea for farming in 1973, there are no breeding studies on developing Korea Israeli carp (domestic) so far. This study performed gene-based cross-breeding studies to restore genetic diversity of lowered Israeli carp through continuous inbreeding, and for rapid growth and better scales. This study produced four cross-breeding groups (F1) using Koean Israeli carp and Chinese Songpu mirror carp for the improvement of growth and scale of Israeli carp in Korea. And mating scheme for breeding groups was set in consideration of the morphological analysis and genetic distance of broodstock. In addition, this study used microsatellite markers and genotype data to analyze genetic diversity and parentage analysis. As a result, the average N_A and H_E values of Korean select broodstock are 8.3 and 0.743, and F1 is 13.0 and 0.764. This study shows that the genetic diversity of F1 has been recovered over Korean Israeli carp through breeding between Korean Israeli carp and Chinese Songpu mirror carp. Common Israeli carp in Korea reached 1.7 kg in 17 months, and improved Israeli carp reached to 2.2 kg. The KC (Korea×China, KC) group was 2.52 and broodstock group was 3.15. F1 showed lower scale score (0.63) than broodstock. The improved carp (F1; CK, KC) had 20% better scales than the parent group (F0), which improved 27% in weight and 25% in scales compared to common Israeli carp. The Israeli carp developed by the genetics-based breeding grew quicker and had improved genetic diversity and fewer scales, which will be of great value for Korean Israeli aquaculture industry due to good marketability.

• Korean Journal of Breeding Science
• /
• 제49권4호
• /
• pp.420-427
• /
• 2017

'Pungwonmi', a new sweetpotato variety, was developed for table use by Bioenergy Crop Research Institute, National Institute of Crop Science (NICS), RDA in 2014. This variety was derived from the cross between 'Benisatsuma' and 'Luby3074' in 2006. The seedling and line selections were performed from 2007 to 2009, and preliminary and advanced yield trials were carried out from 2010 to 2011. The regional yield trials were conducted at five locations from 2012 to 2014, and it was named as 'Pungwonmi'. This variety has cordate leaf shape, and its leaves, stems, nodes, and petioles are green. Storage root of 'Pungwonmi' has an elliptical shape, red skin, and light orange flesh. 'Pungwonmi' was moderately resistant to fusarium wilt, and resistant to root-knot nematode. Dry matter content was 31.2%, and texture of steamed storage root was intermediate. Total sugar content of raw and steamed storage roots of 'Pungwonmi' was higher than that of 'Yulmi'. ${\beta}$-carotene content of 'Pungwonmi' was 9.1 mg/100g DW. Yield of marketable storage root over 50 g of 'Pungwonmi' was 24.3 MT/ha under the early season culture, which was 46% higher than that of 'Yulmi'. The number of marketable storage roots per plant was 2.8 and the average weight of marketable storage root was 156 g under the optimal and late season culture. Marketable storage root yield of 'Pungwonmi' was 24.1 MT/ha under the optimum and late season culture, which was 26% higher than that of 'Yulmi'. (Registration No. 6428).

• Korean Journal of Breeding Science
• /
• 제42권6호
• /
• pp.679-683
• /
• 2010

'Yeonjami' is a new sweetpotato variety developed for table use by Bioenergy Crop Research Center, National Institute of Crop Science (NICS), RDA in 2008. This variety was selected from the cross between 'Ayamurasakki' and 'Poly Cross' in 2000, and seedling and line selections were practiced from 2001 to 2003. Preliminary and advanced yield trials were carried out from 2004 to 2005. The regional yield trials were conducted at six locations from 2006 to 2008. 'Yeonjami' has cordate leaf, green vine and petiole, long elliptic storage root, purple skin and light purple flesh color of storage root. The average yield of storage root was 25.9 ton/ha in the regional yield trials, which was 15% higher than that of 'Sinjami' variety. Number of storage roots over 50 gram per plant was 2.9, and the average weight of one storage root was 153 gram. This variety was partly-resistant to Fusarium wilt and nematode. In addition, steamed 'Yeonjami' has higher polyphenol contents as 139.6 mg/100 g and higher biological activities as, which may improve the bioactivity in human.

• Journal of the Korean Electrochemical Society
• /
• 제22권1호
• /
• pp.36-42
• /
• 2019

A macroporous Sn thick film as a high capacity negative electrode for a lithium ion secondary battery was prepared by using a chemical etching method using nitric acid for a Sn film having a thickness of $52{\mu}m$. The porous Sn thick film greatly reduced the over-voltage for the alloying reaction with lithium by the increased reaction area. At the same time. The porous structure of active Sn film plays a part in the buffer and reduces the damage by the volume change during cycles. Since the porous Sn thick film electrode does not require the use of the binder and the conductive carbon black, it has substantially larger energy density. As the concentration of nitric acid in etching solution increased, the degree of the etching increased. The etching of the Sn film effectively proceeded with nitric acid of 3 M concentration or more. The porous Sn film could not be recovered because the most of Sn was eluted within 60 seconds by the rapid etching rate in the 5 M nitric acid. In the case of etching with 4 M nitric acid for 60 seconds, the appropriate porous Sn film was formed with 48.9% of weight loss and 40.3% of thickness change during chemical acid etching process. As the degree of etching of Sn film increased, the electrochemical activity and the reversible capacity for the lithium storage of the Sn film electrode were increased. The highest reversible specific capacity of 650 mAh/g was achieved at the etching condition with 4 M nitric acid. The porous Sn film electrode showed better cycle performance than the conventional electrode using a Sn powder.

• Korean Journal of Environmental Agriculture
• /
• 제38권3호
• /
• pp.166-172
• /
• 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.

• Journal of Astronomy and Space Sciences
• /
• 제36권1호
• /
• pp.21-33
• /
• 2019

This paper focuses on the interpretation of radiation fluxes from active galactic nuclei. The advantage of positron annihilation spectroscopy over other methods of spectral diagnostics of active galactic nuclei (therefore AGN) is demonstrated. A relationship between regular and random components in both bolometric and spectral composition of fluxes of quanta and particles generated in AGN is found. We consider their diffuse component separately and also detect radiative feedback after the passage of high-velocity cosmic rays and hard quanta through gas-and-dust aggregates surrounding massive black holes in AGN. The motion of relativistic positrons and electrons in such complex systems produces secondary radiation throughout the whole investigated region of active galactic nuclei in form of cylinder with radius R= 400-1000 pc and height H=200-400 pc, thus causing their visible luminescence across all spectral bands. We obtain radiation and electron energy distribution functions depending on the spatial distribution of the investigated bulk of matter in AGN. Radiation luminescence of the non-central part of AGN is a response to the effects of particles and quanta falling from its center created by atoms, molecules and dust of its diffuse component. The cross-sections for the single-photon annihilation of positrons of different energies with atoms in these active galactic nuclei are determined. For the first time we use the data on the change in chemical composition due to spallation reactions induced by high-energy particles. We establish or define more accurately how the energies of the incident positron, emitted ${\gamma}-quantum$ and recoiling nucleus correlate with the atomic number and weight of the target nucleus. For light elements, we provide detailed tables of all indicated parameters. A new criterion is proposed, based on the use of the ratio of the fluxes of ${\gamma}-quanta$ formed in one- and two-photon annihilation of positrons in a diffuse medium. It is concluded that, as is the case in young supernova remnants, the two-photon annihilation tends to occur in solid-state grains as a result of active loss of kinetic energy of positrons due to ionisation down to thermal energy of free electrons. The single-photon annihilation of positrons manifests itself in the gas component of active galactic nuclei. Such annihilation occurs as interaction between positrons and K-shell electrons; hence, it is suitable for identification of the chemical state of substances comprising the gas component of the investigated media. Specific physical media producing high fluxes of positrons are discussed; it allowed a significant reduction in the number of reaction channels generating positrons. We estimate the brightness distribution in the ${\gamma}-ray$ spectra of the gas-and-dust media through which positron fluxes travel with the energy range similar to that recorded by the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) research module. Based on the results of our calculations, we analyse the reasons for such a high power of positrons to penetrate through gas-and-dust aggregates. The energy loss of positrons by ionisation is compared to the production of secondary positrons by high-energy cosmic rays in order to determine the depth of their penetration into gas-and-dust aggregations clustered in active galactic nuclei. The relationship between the energy of ${\gamma}-quanta$ emitted upon the single-photon annihilation and the energy of incident electrons is established. The obtained cross sections for positron interactions with bound electrons of the diffuse component of the non-central, peripheral AGN regions allowed us to obtain new spectroscopic characteristics of the atoms involved in single-photon annihilation.