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A Comparative Study of Physiological Activity and Ingredient Analysis of Glycyrrhiza uralensis Fischer Stems and Leaves Cultivated with Different Wavelength of LED Lights (LED광원에 따른 감초 지상부의 생리활성 및 성분 평가)

  • Bang, Keuk Soo;Chang, Young Nam;Jin, Jong Sik;Park, Sang A;Lim, Jae Soo;Park, Jeong Sub;Kim, Jong Sung;Lee, Jeong Ho
    • Korean Journal of Plant Resources
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    • v.28 no.1
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    • pp.126-134
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    • 2015
  • Glycyrrhiza uralensis Fischer is one of the most commonly used herbs. Recently, the stem and leave of the plant have been interested in physiological activities because the aerial parts have been thrown away. Finding out cultivation method of Glycyrrhiza uralensis Fischer to improve chemical ingredients and biological activities has been tried these days. In this study, different wavelengths of light emitting diode (LED) were used for a cultivation of Glycyrrhiza uralensis Fischer. Antioxidant activities and inhibitory effect on mutagenecity of samples were evaluated. The stem and leave cultivated under blue light (BL-0) showed the strongest antioxidant activities of $3.02{\pm}0.13{\mu}g/ml$ ($EC_{50}$) and $2.18{\pm}0.18{\mu}g/ml$ ($EC_{50}$) in DPPH and ABTS radical scavenging test, respectively. Total phenolic content of BL-0 was $2.93{\pm}0.11g/100g$, the highest value between cultivation conditions. However, antioxidant activities of the stem and leave cultivated under red light were the weakest between samples. All of the stem and leave used in this study showed inhibitory effect on mutagenecity of 1-nitropyrene. BL-0 showed stronger inhibitory effects on mutagenicity of Trp-P-1, Trp-P-2, and AFB1 than samples cultivated under other conditions. Only on mutagenecity of 2-aminoanthracene, the stem and leave cultivated at 1 m apart from red light (RL-1) showed the strongest inhibitory effect. These results indicate that blue LED might be the most effective condition for improvement of physiological activities for the aerial parts of Glycyrrhiza uralensis Fischer in cultivation. The components were identified with GC/MS. Cytidine was detected only in RL-1 at 25 min of retention time and 2-bromotrimethylene glycol was detected only in BL-0 at 37 min.

Study on the Relationship between Utilization of Nutrients in the Rumen and Rumen Microorganisms by Dietary Energy and Protein Source (에너지와 단백질(蛋白質) 공급원(供給源)에 의(依)한 반추위내(反芻胃內) 영양소(營養素) 이용성(利用性) 및 반추위미생물(反芻胃微生物)에 관(關)한 연구(硏究))

  • Chee, Sul Ha;Lee, Sang Cheol;Jeong, Ha Yeon
    • Korean Journal of Agricultural Science
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    • v.23 no.2
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    • pp.188-205
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    • 1996
  • This study was conducted to examine the effects of dietary energy and protein sources on the rumen microbial population of sheep. The results obtained were summarized as the follows; 1. Ruminal pH was highest in sheep fed the diet rapidly degraded in the rumen(F-F) as a energy (barley plus beet pulp) and protein source (rapeseed meal), and lowest in the diet (F-S) of rapidly degradable energy source plus slowly degradable protein source (corn gluten meal + cotton seed meal) without affecting by postfeeding time. 2. Ruminal ammonia concentration was higher in corn (slowly degradable) for energy source and rapeseed meal (rapidly degradable) for protein source (S-F) than others, and abruptly increased at 1 hr after feeding regardless of treatments. 3. Concentration of ruminal total volatile fatty acid, acetate and propionate were highest in F-S and peaked at 1 hr after feeding firstly and formed second peak at 9hrs, respectively. 4. Digestibilities of the proximates and ADF were not affected by treatment but NDF was highest in F- F. 5. Nitrogen retention was highest in S-F and lowest in F-F and F-S. 6. Digestibility and metabolizability of energy, contents of OCP, TDN, DE and ME were not affected by treatment.

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Bioactive Materials and Biological Activity in the Extracts of Leaf, Stem Mixture and Root from Angelica gigas Nakai (참당귀 잎, 줄기혼합물과 뿌리 추출물의 생리활성물질 및 그 활성작용)

  • Heo, Jin-Sun;Cha, Jae-Young;Kim, Hyun-Woo;Ahn, Hee-Young;Eom, Kyung-Eun;Heo, Su-Jin;Cho, Young-Su
    • Journal of Life Science
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    • v.20 no.5
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    • pp.750-759
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    • 2010
  • The bioactive materials (phenolic compounds, flavonoids, minerals, decursin and decursinol angelate) and biological activities (DPPH [$\alpha,\alpha$'-diphenyl-$\beta$-picrylhydrazyl] free radical scavenging capability, reducing power, and tyrosinase activity) in the extracts of leaf, stem mixture (AGLS), and root (AGR) from Angelica gigas Nakai were examined by using water, hot water and ethanol solvent. The highest extract yield (21.89%) was found in the water extract of AGR. The highest concentrations of phenolic compounds and flavonoids in the ethanol extracts of AGLS and AGR were 14.99% and 14.79%. Major minerals of AGLS and AGR were K, Mg, Fe, Na and Ca. Decursin and decursinol angelate were the major ingredients of Angelica gigas, detected at 18.71 and 18.89 min of retention time by HPLC analysis, respectively. The highest concentrations of decursin and decursinol angelate in the Angelica gigas ethanol extract were found in root ($41.7\;{\mu}g/g$) and leaf ($34.04\;{\mu}g/g$). The highest free radical scavenging activity was found in the hot water extracts of AGLS and AGR, and its activity was stronger in all extracts of AGLS than AGR. The highest reducing power was found in the ethanol extracts of AGLS and AGR and this was dependent on the sample concentration. The hot water extracts of AGLS and AGR revealed the highest inhibition activity on tyrosinase. Overall, these results may provide the basic data needed to understand the biological activities of bioactive materials derived from Angelica gigas.

Phosphorous Removal in a Free Water Surface Wetland Constructed on the Gwangju Stream Floodplain (광주천 고수부지에 조성한 자유수면인공습지의 인 제거)

  • Yang, Hong-Mo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.1
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    • pp.100-109
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    • 2012
  • Removal rates of $PO_4-P$ and TP in a free water surface wetland system were investigated. The system was established in 2008 on a floodplain in the middle reach of the Gwangju Stream flowing through Gwangju City. Its dimensions were 46 meters in length and 5 meters in width. Two year old Typha angustifloria L. growing in pots were planted on half of the area and Zizania latifolia Turcz on the other half in 2008. Stream water was funneled into the wetlands by gravity flow, and its effluent was discharged back into the stream. The influent volume was controlled by valves and water depth was adjusted by wires. Volume and water quality of inflow and outflow were analyzed from January to December in 2010. Inflow into the system averaged approximately $710m^3/day$ and hydraulic residence time was about 1.5 hours. Average influent and effluent $PO_4-P$ concentration were 0.144 and 0.103mg/L, respectively, and $PO_4-P$ abatement amounted to 28.6%. Influent and effluent TP concentration averaged 0.333 and 0.262mg/L, respectively, and TP retention reached to 20.7%.$PO_4-P$ removal rate(%) during plant growing season(31.448) was significantly high(p<0.001) when compared with that during plant non-growing season(25.829). TP abatement rate(%) during plant growing season(27.230) was also significantly high(p<0.001) when compared with that of the non-growing season(14.856). Major phosphorous removals in the system resulted from adsorption of phosphorous in the litter-soil layers; sedimentation of particulate phosphorous and Ca, Al, Fe bounded phosphates; and absorption of phosphorous by emergent plants. The adsorption and sedimentation occurred throughout the year, however, the absorption took place during plant growing season. This resulted in higher removals of $PO_4-P$ and TP during plant growing season.

Characteristics of Si Floating Gate Nonvolatile Memory Based on Schottky Barrier Tunneling Transistor (쇼트키 장벽 관통 트랜지스터 구조를 적용한 실리콘 나노점 부유 게이트 비휘발성 메모리 특성)

  • Son, Dae-Ho;Kim, Eun-Kyeom;Kim, Jeong-Ho;Lee, Kyung-Su;Yim, Tae-Kyung;An, Seung-Man;Won, Sung-Hwan;Sok, Jung-Hyun;Hong, Wan-Shick;Kim, Tae-You;Jang, Moon-Gyu;Park, Kyoung-Wan
    • Journal of the Korean Vacuum Society
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    • v.18 no.4
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    • pp.302-309
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    • 2009
  • We fabricated a Si nano floating gate memory with Schottky barrier tunneling transistor structure. The device was consisted of Schottky barriers of Er-silicide at source/drain and Si nanoclusters in the gate stack formed by LPCVD-digital gas feeding method. Transistor operations due to the Schottky barrier tunneling were observed under small gate bias < 2V. The nonvolatile memory properties were investigated by measuring the threshold voltage shift along the gate bias voltage and time. We obtained the 10/50 mseconds for write/erase times and the memory window of $\sim5V$ under ${\pm}20\;V$ write/erase voltages. However, the memory window decreased to 0.4V after 104seconds, which was attributed to the Er-related defects in the tunneling oxide layer. Good write/erase endurance was maintained until $10^3$ write/erase times. However, the threshold voltages moved upward, and the memory window became small after more write/erase operations. Defects in the LPCVD control oxide were discussed for the endurance results. The experimental results point to the possibility of a Si nano floating gate memory with Schottky barrier tunneling transistor structure for Si nanoscale nonvolatile memory device.

Analysis of Quality and Processing Suitability of Mixed Seeding and Flour Blending between Wheat Varieties (밀 품종 혼파와 밀가루 혼합에 따른 품질 및 가공적성 분석)

  • Kim, Kyeong-Min;Kim, Kyeong-Hoon;Kang, Chon-Sick;Jeong, Han young;Choi, Chang-Hyun;Park, Jinhee;Son, Jae-Han;Yang, Jinwoo;Kim, Young-Jin;Park, Tae-Il;Kweon, Meera
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.64 no.3
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    • pp.225-233
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    • 2019
  • This study was conduct to investigate the effect of mixed seed sowing and flour blending on the uniformity of flour quality of Korean domestic wheat. Two wheat varieties (Keumkang and Baegjoong) were selected for sowing mixed seeds, and their growth characteristics and flour quality were analyzed. Quality of flour blending with the same varieties was also evaluated. The ratios for mixed seed sowing and flour blending were from 0 to 100% with a 10% increase of interval for each treatment. On increasing the portion of Baegjoong in mixed seed sowing, the heading time was a little delayed, however, yield increased. The results of the flour quality showed lower damaged starch content and sodium carbonate SRC (solvent retention capacity) value for Keumkang than for Baegjoong. Protein quantity by protein content and quality by SDSS (Sodium Dodecyle Sulfate-Sedimentation) volume, lactic acid SRC, and mixograph pattern of Keumkang were superior to those of Baegjoong. Compared with mixed seed sowing, overall quality characteristics of flours with different ratios showed predictable and proportional change by flour blending. This demonstrated the successful application of flour blending, compared with mixed seed sowing, for improving the uniformity of flour quality.

The Records and Archives Administrative Reform in China in 1930s (1930년대 중국 문서당안 행정개혁론의 이해)

  • Lee, Won-Kyu
    • The Korean Journal of Archival Studies
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    • no.10
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    • pp.276-322
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    • 2004
  • Historical interest in China in 1930s has been mostly focused on political characteristic of the National Government(國民政府) which was established by the KMT(中國國民黨) as a result of national unification. It is certain that China had a chance to construct a modern country by the establishment of the very unified revolutionary government. But, it was the time of expanding national crises that threatened the existence of the country such as the Manchurian Incident and the Chinese-Japanese War as well as the chaos of the domestic situation, too. So it has a good reason to examine the characteristic and pattern of the response of the political powers of those days. But, as shown in the recent studies, the manifestation method of political power by the revolutionary regime catches our attention through the understanding of internal operating system. Though this writing started from the fact that the Nationalist Government executed the administrative reform which aimed at "administrative efficiency" in the middle of 1930s, but it put stress on the seriousness of the problem and its solution rather than political background or results. "Committee on Administrative Efficiency(行政效率委員會)", the center of administrative reform movement which was established in 1934, examined the plan to execute the reform through legislation by the Executive Council(行政院) on the basis of the results of relevant studies. They claimed that the construction of a modern country should be performed by not political revolution anymore but by gradual improvement and daily reform, and that the operation of the government should become modern, scientific and efficient. There were many fields of administrative reform subjects, but especially, the field of records and archives adminstration(文書檔案行政) was studied intensively from the initial stage because that subject had already been discussed intensively. They recognized that records and archives were the basic tool of work performance and general activity but an inefficient field in spite of many input staff members, and most of all, archival reform bring about less conflicts than the fields of finance, organization and personnel. When it comes to the field of records adminstration, the key subjects that records should be written simply, the process of record treatment should be clear and the delay of that should be prevented were already presented in a records administrative meeting in 1922. That is, the unified law about record management was not established, so each government organization followed a conventional custom or performed independent improvement. It was through the other records administrative workshop of the Nationalist Government in 1933 when the new trend was appeared as the unified system improvement. They decided to unify the format of official records, to use marker and section, to unify the registration of receipt records and dispatch records and to strengthen the examination of records treatment. But, the method of records treatment was not unified yet, so the key point of records administrative reform was to establish a unified and standard record management system for preventing repetition by simplifying the treatment procedure and for intensive treatment by exclusive organizations. From the foundation of the Republic of China to 1930s, there was not big change in the field of archives administration, and archives management methods were prescribed differently even in the same section as well as same department. Therefore, the point at issue was to centralize scattered management systems that were performed in each section, to establish unified standard about filing and retention period allowance and to improve searching system through classification and proper number allowance. Especially, the problem was that each number system and classification system bring about different result due to dual operation of record registration and archives registration, and that strict management through mutual contrast, searching and application are impossible. Besides, various problems such as filing tools, arrangement method, preservation facilities & equipment, lending service and use method were raised also. In the process this study for the system improvement of records and archives management, they recognized that records and archives are the identical thing and reached to create a successive management method of records and archives called "Records and Archives Chain Management Method(文書檔案連鎖法)" as a potential alternative. Several principles that records and archives management should be performed unitedly in each organization by the general record recipient section and the general archives section under the principle of task centralization, a consistent classification system should be used by classification method decided in advance according to organizational constitution and work functions and an identical number system should be used in the process of record management stage and archive management stage by using a card-type register were established. Though, this "Records and Archives Chain Management Method" was developed to the stage of test application in several organizations, but it was not adopted as a regular system and discontinued. That was because the administrative reform of the Nationalist Government was discontinued by the outbreak of the Chinese-Japanese War. Even though the administrative reform in the middle of 1930s didn't produce practical results but merely an experimentation, it was verified that the reform against tradition and custom conducted by the Nationalist Government that aimed for the construction of a modern country was not only a field of politics, but on the other hand, the weak basis of the government operation became the obstacle to the realization of the political power of the revolutionary regime. Though the subject of records and archives administrative reform was postponed to the future, it should be understood that the consciousness of modern records and archives administration and overall studies began through this examination of administrative reform.

Analysis of Heat Transfer Characteristics on Multi-layer Insulating Curtains Coated with Silica Aerogel (실리카 에어로겔이 흡착된 다겹보온커튼의 전열 특성 분석)

  • Jin, Byung-Ok;Kim, Hyung-Kweon;Ryou, Young-Sun;Lee, Tae-Seok;Kim, Young-Hwa;Oh, Sung-Sik;Kang, Geum-Choon
    • Journal of Bio-Environment Control
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    • v.28 no.3
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    • pp.273-278
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    • 2019
  • The multi-layer insulating curtains used in the experiment was produced in six combinations using non-woven fabric containing aerogel and compared and analyzed by measuring heat flux and heat perfusion rates due to weight, thickness and temperature changes. Using silica aerogel, which have recently been noted as new material insulation, this study tries to produce a new combination of multi-layer insulating curtains that can complement the shortcomings of the multi-layer insulating curtains currently in use and maintain and improve its warmth, and analyze the thermal properties. The heat flux means the amount of heat passing per unit time per unit area, and the higher the value, the more heat passing through the multi-layer insulating curtain, and it can be judged that the heat retention is low. The weight and thickness of multi-layer insulation curtains were found to be highly correlated with thermal insulation. In particular, insulation curtains combined with aerogel meltblown non-woven fabric had relatively higher thermal insulation than insulation curtains with the same number of insulation materials. However, the aerogel meltblown non-woven fabric is weak in light resistance and durability, and there is a problem that the production process and aerogel are scattering. In order to solve this problems, the combination of expanded aerogel non-woven fabric and hollow fiber non-woven fabric, which are relatively simple manufacturing processes and excellent warmth, are suitable for use in real farms.

The Ecological Values of the Korean Demilitarized Zone(DMZ) and International Natural Protected Areas (비무장지대(DMZ)의 생태적 가치와 국제자연보호지역)

  • Cho, Do-soon
    • Korean Journal of Heritage: History & Science
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    • v.52 no.1
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    • pp.272-287
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    • 2019
  • The Korean Demilitarized Zone (DMZ) was established in 1953 by the Korean War Armistice Agreement. It extends from the estuary of the Imjin River, in the west, to the coast of the East Sea. It is 4 km in width and 148 km in length. However, the ecosystems of the civilian control zone (CCZ) located between the southern border of the DMZ and the civilian control line (CCL) and the CCZ in the estuary of the Han River and the Yellow Sea are similar to those in the DMZ, and, therefore, the ecosystems of the DMZ and the CCZ are collectively known as the "ecosystems of the DMZ and its vicinities." The flora in the DMZ and its vicinities is composed of 1,864 species, which accounts for about 42% of all the vascular plant species on the Korean Peninsula and its affiliated islands. Conducting a detailed survey on the vegetation, flora, and fauna in the DMZ is almost impossible due to the presence of landmines and limitations on the time allowed to be spent in the DMZ. However, to assess the environmental impact of the Munsan-Gaesong railroad reconstruction project, it was possible to undertake a limited vegetation survey within the DMZ in 2001. The vegetation in Jangdan-myeon, in Paju City within the DMZ, was very simple. It was mostly secondary forests dominated by oaks such as Quercus mongolica, Q. acutissima, and Q. variabilis. The other half of the DMZ in Jangdan-myeon was occupied by grassland composed of tall grasses such as Miscanthus sinensis, M. sacchariflorus, and Phragmites japonica. Contrary to the expectation that the DMZ may be covered with pristine mature forests due to more than 60 years of no human interference, the vegetation in the DMZ was composed of simple secondary forests and grasslands formed on former rice paddies and agricultural fields. At present, the only legal protection system planned for the DMZ is the Natural Environment Conservation Act, which ensures that the DMZ would be managed as a nature reserve for only two years following Korean reunification. Therefore, firstly, the DMZ should be designated as a site of domestic legally protected areas such as nature reserve (natural monument), scenic site, national park, etc. In addition, we need to try to designate the DMZ as a UNESCO Biosphere Reserve or as a World Heritage site, or as a Ramsar international wetland for international cooperation. For nomination as a world heritage site, we can emphasize the ecological and landscape value of the wetlands converted from the former rice paddies and the secondary forests maintained by frequent fires initiated by military activities. If the two Koreas unexpectedly reunite without any measures in place for the protection of nature in the DMZ, the conditions prior to the Korean War, such as rice paddies and villages, will return. In order to maintain the current condition of the ecosystems in the DMZ, we have to discuss and prepare for measures including the retention of mines and barbed-wire fences, the construction of roads and railroads in the form of tunnels or bridges, and the maintenance of the current fire regime in the DMZ.

Water Digital Twin for High-tech Electronics Industrial Wastewater Treatment System (II): e-ASM Calibration, Effluent Prediction, Process selection, and Design (첨단 전자산업 폐수처리시설의 Water Digital Twin(II): e-ASM 모델 보정, 수질 예측, 공정 선택과 설계)

  • Heo, SungKu;Jeong, Chanhyeok;Lee, Nahui;Shim, Yerim;Woo, TaeYong;Kim, JeongIn;Yoo, ChangKyoo
    • Clean Technology
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    • v.28 no.1
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    • pp.79-93
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    • 2022
  • In this study, an electronics industrial wastewater activated sludge model (e-ASM) to be used as a Water Digital Twin was calibrated based on real high-tech electronics industrial wastewater treatment measurements from lab-scale and pilot-scale reactors, and examined for its treatment performance, effluent quality prediction, and optimal process selection. For specialized modeling of a high-tech electronics industrial wastewater treatment system, the kinetic parameters of the e-ASM were identified by a sensitivity analysis and calibrated by the multiple response surface method (MRS). The calibrated e-ASM showed a high compatibility of more than 90% with the experimental data from the lab-scale and pilot-scale processes. Four electronics industrial wastewater treatment processes-MLE, A2/O, 4-stage MLE-MBR, and Bardenpo-MBR-were implemented with the proposed Water Digital Twin to compare their removal efficiencies according to various electronics industrial wastewater characteristics. Bardenpo-MBR stably removed more than 90% of the chemical oxygen demand (COD) and showed the highest nitrogen removal efficiency. Furthermore, a high concentration of 1,800 mg L-1 T MAH influent could be 98% removed when the HRT of the Bardenpho-MBR process was more than 3 days. Hence, it is expected that the e-ASM in this study can be used as a Water Digital Twin platform with high compatibility in a variety of situations, including plant optimization, Water AI, and the selection of best available technology (BAT) for a sustainable high-tech electronics industry.