The purpose of this study was to evaluate the effects of different Hydraulic Retention Times (HRTs) on the contaminant removal efficiency using Aerobic Granular Sludge (AGS). A laboratory-scale experiment was performed using a sequencing batch reactor, and the Chemical Oxygen Demand (COD), nitrogen, orthophosphate removal efficiency, AGS/MLSS ratio, and precipitability in accordance with the HRT were evaluated. As a result, the COD removal efficiency was not significantly different with the reduction in HRT, and at a HRT of 6 h, the removal rate was slightly increased owing to the increase in organic loading rate. The nitrogen removal efficiency was improved by injection of influent division at a HRT of 6 h. As the HRT decreased, the MLSS and AGS tended to increase, and the sludge volume index finally decreased to 50 mL/g. In addition, the size of the AGS gradually increased to about 1.0 mm. Therefore, the control of HRT provides favorable conditions for the stable formation of AGS, and is expected to improve the contaminant removal efficiency with the selection of a proper operation strategy.
The purpose of this study was to evaluate the effect of high-salinity wastewater on the microbial activity of Aerobic Granule Sludge (AGS). Laboratory-scale experiments were performed using a sequencing batch reactor, and the Chemical Oxygen Demand (COD), nitrogen removal efficiency, sludge precipitability, and microbial activity were evaluated under various salinity injection. The COD removal efficiency was found to decrease gradually to 3.0% salinity injection, and it tended to recover slightly from 4.0%. The specific nitrification rate was 0.043 0.139 mg NH4 +-N/mg MLVSS·day. The specific denitrification rate was 0.069 0.108 mg NO3 --N/mg MLVSS·day. The sludge volume index (SVI30) ultimately decreased to 46 mL/g. The specific oxygen uptake rate decreased from an initial value 120.3 to a final value 70.7 mg O2/g MLVSS·hr. Therefore, salinity injection affects the activity of AGS, causing degradation of the COD and nitrogen removal efficiency. It can be used as an indicator to objectively determine the effect of salinity on microbial activity.
The purpose of this study is to biological treatment of high salinity wastewater using Aerobic Granular Sludge (AGS). In laboratory scale’s experiments research was performed using a sequencing batch reactor, and evaluation of the denitrification reaction in accordance with the injection condition of salinity concentration, surface properties of microorganisms, and sludge precipitability was performed. The results showed that the salinity concentration increased up to 1.5%, and there was no significant difference in the nitrogen removal efficiency; however, it showed a tendency to decrease gradually from 2.0% onward. The specific denitrification rate (SDNR) was 0.052 0.134 mg NO3 --N/mg MLVSS (mixed liquor volatile suspended solid)·day. The MLVSS/MLSS (mixed liquor suspended solid) ratio decreased to 76.2%, and sludge volume index (SVI30) was finally lowered to 57 mL/g. Using an optical microscope, it was also observed that the initial size of the sludge was 0.2 mm, and finally it was formed to 0.8-1.0 mm. Therefore, salinity injection provides favorable conditions for the formation of an AGS, and it was possible to maintain stable granular sludge during long-term operation of the biological treatment system.
본 연구는 2009년 시범사업으로 시작된 대체교사 지원사업 제도를 진단하고 향후 방향을 모색하기 위한 기초연구로 3개시 어린이집 원장 221명, 교사 590명, 총 811명을 대상으로 원장과 교사의 배경별 대체교사 지원사업 이용여부, 대체교사 지원사업에 대한 원장과 교사의 인식, 대체교사 지원사업 이용 경험이 있는 원장과 교사의 인식, 대체교사 지원사업을 이용해보지 않은 원장과 교사의 대체교사 지원사업 이용 실태와 인식을 조사하였다. 연구결과, 원장과 특히 교사를 대상으로 대체교사 지원사업에 대한 적극적 안내가 필요하며, 대체교사 지원 수요에 비하여 대체교사 지원이 부족한 것으로 나타나 대체교사 인력확충이 필요한 것으로 판단된다. 또한 보육교사의 자유로운 연차사용 환경조성과 이에 대한 사회적 인식의 변화와 제도적 뒷받침이 필요함을 알 수 있다.
이 연구는 초급 한국어 학습자를 대상으로 울타리어 사용과 학습자들의 화용능력의 상관관계를 알아보고 한국어 교육에서의 울타리어 교육의 필요성을 확인하였다. 화용능력의 한 요소라고 할 수 있는 울타리어와 관련하여 초급 한국어 학습자들의 실제 교실 담화를 대상으로 사용 양상을 분석하였다. 분석 결과를 보면 화용능력이 낮은 초급 학습자들은 울타리어 사용 역시 매우 제한적임을 알 수 있었 다. 울타리어를 사용하지 않아도 의미전달은 가능하지만 의미의 왜곡을 초래하는 등의 화용적인 문제가 될 수 있다는 점에서 상대적으로 어휘력이 풍부하지 못한 초급 한국어 학습자들에게 울타리어 교육은 학습자들의 화용능력을 발달시키는 중요한 요소라고 볼 수 있다.
This study was conducted to evaluate roughage to concentrate ratio on the changes of productivity and metabolic profiling in milk. Six lactating Holstein cows were divided into two groups, T1 group was fed low-concentrate diet (Italian ryegrass to concentrate ratio = 8:2) and T2 group was fed high-concentrate diet (Italian ryegrass to concentrate ratio = 2:8). Milk samples were collected and its components and metabolites were analyzed by 1H-NMR (Nuclear magnetic resonance). The result of milk components such as milk fat, milk protein, solids-not-fat, lactose and somatic cell count were not significantly different between two groups. In carbohydrate metabolites, trehalose and xylose were significantly higher (P<0.05) in T1 group, however lactose was not significantly different between two groups. In amino acid metabolites, glycine was the highest concentration however, there was no signifi-cant difference observed between two groups. Urea and methionine were significantly higher (P<0.05) in the T2 group. In lipid metabolites, carnitine, choline and O-acetylcarnitine there were no significant difference observed between the two groups. In benzoic acid metabolites, tartrate was significantly higher (P<0.05) in T2 group. In organic acid metabolites, acetate was significantly higher (P<0.05) in T1 group and fumarate was significantly higher (P<0.05) in T2 group. In the other metabolites, 3-methylxanthine was only significantly higher (P<0.05) in T2 group and riboflavin was only significantly higher (P<0.05) in T1 group. As a result, milk components were not significantly different between two groups. However, metabolites concentration in the milk was significantly different depends on roughage to concentrate ratio.
The this study was carried out to investigate the growth characteristics of wild-simulated ginseng by direct seeding and transplanting cultivation for develop standard cultivation techniques of wild-simulated ginseng. Bonghwa experimental field were confirm to be suitable location environment for cultivation of wild-simulated ginseng. As a result of this study, the germination rate of wild-simulated ginseng was significantly highest when seed size was over 6.5 ㎜ in the spot seeding cultivation. In the case of transplanting, survival rate was significantly increased when the diameter of root was over 10 ㎜, planting distance was 7 ㎝, and the thickness of soil covering was less then 2 ㎝. The result of growth characteristics of wild-simulated ginseng by cultivation type, growth of stem in spot seeding cultivation was showed significantly increased when seed size over 6 ㎜, seeding number was 3 grains, and the seeding distance was less then 5 ㎝. Strip seeding cultivation was showed significantly increased in stem and root growth when seeding distance was 30 ㎝ grains and quantity of seeding was less then 23 g. In the case of transplanting cultivation, it’s was showed significantly increased in stem growth when diameter of root was over then 10 ㎜ and direction of rhizome was top and bottom. The results of this study was that to clearly establish the techniques of cultivation of managements and it’s will be suggest contribute to the industrial activation of wild-simulated ginseng.
This research aims to detect delamination-like damage from asphalt-concrete interface using contactless ultrasonic technique. FEM simulation and experiments demonstrate that surface waves and S mode are strongly present when there is delamination-like damage. It is believed that the measurement of S mode by non-contact ultrasonic system will allow one to determine the existence of delamination-like damage from bridge decks.
본 연구는 금 정광에 함유된 비소(As) 및 비스무스(Bi)와 같은 페널티 원소(penalty elements)를 제거하기 위한 목적으로 마이크로웨이브-질산침출을 이용하였다. 또한, 금 정광 시료로부터 금 함량을 증가시키고자 하였다. 침출조건은 페널티 원소의 제거를 향상시키기 위해 질산농도, 침출시간 그리고 고액비를 변화하였다. 실험결과 고체-잔류물에서 시료무게 감소율, 비소와 비스무스의 제거율 그리고 금 함량은 질산농도와 침출시간이 증가할수록 그리고 고액비가 감소할수록 증가하였다. 최대 비소와 비스무스 제거율 및 금 함량이 얻어지는 침출조건은 질산용액의 농도 6 M, 침출시간 5분이었다. 이 때, 고체-잔류물 시료의 무게 감소는 87 %, 비소 제거율은 98.23 %, 비스무스는 거의 제거(100 %)되었고 금 함량은 81.36 g/t에서 487.32 g/t으로 증가하였다. 고체-잔류물을 XRD로 분석한 결과, 질산농도가 증가할수록 황철석 피크들은 사라지고 반면에, 원소 황의 피크들이 증가하였다.
Temporal and spatial variations in surface ozone concentrations in Busan were investigated by using observation data from urban air quality sites during 2001-2016. The annual ozone concentrations showed a significant increasing trend of +0.40 ppb yr-1 in this period, with a more rapid increase of +0.81 ppb yr-1 since 2010. For the monthly analysis, the increase in ozone concentration was the greatest in August (+0.68 ppb yr-1). These ozone trends were due mainly to rising temperature (+0.05℃ yr-1) and weak decreasing precipitation (-6.42 mm yr-1). However, the extreme weather events (heat wave, localized heavy rain, etc.) lead to an increase in short-term variability of ozone since 2010. The relatively low ozone concentrations in the downtown area were caused by high NOx emissions from mobile sources. The increases in ozone concentrations were observed at most of the air quality monitoring sites due to the reductions in anthropogenic emissions of NOx during 2001-2015. However, in the southern coastal area, lower rates of increase in ozone concentrations were observed by –0.10~0.25 ppb yr-1 due to the significant NOx emitted by ships in the Busan port and Busan new port.
본 연구는 전라남도 여수시 돌산읍에 위치하는 돌산도의 관속식물상을 조사하고 분포가 확인된 주요 식물에 대해 논의하였다. 현지조사는 2017년부터 2018년까지 총 15회에 걸쳐 수행되었으며, 이에 대한 증거표본은 국립수목원 산림생물표본관(KH)에 소장하였다. 분포가 확인된 관속식물은 113과 338속 517종 1아종 49변종 3품종 총 570분류군이다. 이중 한국특산식물은 개족도리풀 등 18분류군을 확인되었으며, 환경부지정 식물구계학적특정식물종은 V-I등급으로 총 90분류군이 조사되었다. 희귀식물은 위기종(EN)인 백양꽃 1분류군을 포함하여 총 4분류군이며, 적색목록에 속하는 관속식물은 취약종(VU) 갯취 등 총 8분류군이다.
Background: Camellia sinensis L.(CS) is a perennial evergreen species of plant whose leaves are used to produce tea. In this plant species, the parts used are the leaves, sub-branch parts are thrown out.
Methods and Results: Ethanol extract of sub-branch parts was used for isolation of major compounds by column chromatography. Structures were identified as caffeine (1), (-)-epicatechin (2) and (-)-epicatechin gallate (3) by interpretation of spectroscopic analysis, including 1H- and 13C-NMR. High-performance liquid chromatography (HPLC) method was used to compare the quantitative level of marker compounds in various extraction solvents of sub-branch parts of CS. The content of caffeine, (-)-epicatechin, and (-)- epicatechin gallate in 30% ethanol extract showed higher value with 3.28 ± 0.57 ㎎/g, 5.53 ± 0.88 ㎎/g, and 1.29 ± 0.24 ㎎/g, respectively.
Conclusions: These results indicated that not only leaves parts but also sub-branch, could be a good source for the functional material and pharmaceutical industry.
Background: Cnidium officinale Makino and Ligusticum chuanxiong Hort. are important medicinal crops in Korea. However, there is insufficient information on the identification of thrips, which attack these plants. Until now, one species of thrips has been recorded as a main pest.
Methods and Results: To identify the thrips emerging in C. officinale Makino and L. chuanxiong Hort., these plants were independently cultivated in two local areas. Thirty individuals of each plant species were selected randomly and surveyed for the presence of thrips. After confirming the existence of thrips, 100 thrips individuals were collected from each crop using the beating method. To identify thrips species, we performed PCR-restriction fragment length polymorphism (RFLP)-based analysis using ITS2 primer sets. Six thrips species were identified: western flower thrips (Frankliniella occidentalis), flower thrips (F. intonsa), onion thrips (Thrips tabaci), chrysanthemum thrips (T. nigropilosus), chilli thrips (Scirtothrips dorsalis), and grass thrips (Anaphothrips obscurus). The proportion of these species differed between the host plant species.
Conclusions: Six thrips species were major pests of two medicinal crops. Integrated pest management is required to control these thrips species, and will enhance the yield and quality of C. officinale and L. chuanxiong.
본 연구는 세라믹 압출법을 이용하여 납석기반 세라믹 반응매질을 제조하였다. 납석의 광물학적 특성은 XRD, XRF, DSC-TGA 및 제타전위분석을 실시하였으며, 납석기반의 세라믹 반응매질은 다양한 소성온도범위(500~1,300 ℃)에서 수행하였다. 소성온도가 증가할수록 반응매질의 강도는 증가 하였으나, 비표면적은 감소된다. 온도변화에 따른 납석의 무게손실과 구조변화를 XRD, DSC-TGA 및 SEM 분석을 통해 확인하였으며, 엽납석은 소성온도 1,000 ℃에서 pyrophyllite dehydroxylate로 전이되며, 1,300 ℃에서 뮬라이트와 크리스토발라이트로 상변화가 발생된다. 본 연구를 통해 납석은 투수성반응벽체 적용을 위한 반응매질로서 세라믹 지지체 역할을 수행할 수 있을 것으로 판단된다.
This paper deals with the paddle type end of arm tool for rescue robot instead of rescue worker in dangerous environments such as fire, earthquake, national disaster and defense. It is equipped at the dual arm manipulator of the rescue robot to safely lift up an injured person. It consists of the paddle for lifting person, sensors for detecting insertion of person onto the paddle, sensor for measuring the tilting angle of the paddle, and mechanical compliance part for preventing incidental injuries. The electronics is comprised of the DAQ module to acquire the sensors data, the control module to treat the sensors data and to manage the errors, and the communication module to transmit the sensors data. After optimally designing the mechanical and electronical parts, we successfully made the paddle type end of arm tool and evaluated its performance by using specially designed jigs. The developed paddle type end of arm tool is going to be applied to the rescue robot for performance verification through field testing.
This study was conducted to investigate for the natural methane emission inhibitor as a feed additive no adversely effect on rumen fermentation. Five different Control (Wheat barn (0.05 g), MRA(Methane Reduction Additive)-1 (Allium fistulosum L. (0.05 g)), MRA-2 (Sodium Lauryl Sulfate (0.025 g) +Wheat barn (0.025 g) mixed), MRA-3 (Sodium Dodecyl Sulfate (0.025 g) + Wheat barn (0.025 g) mixed), and MRA-4 (Allium fistulosum L. (0.02 g) + Tannic acid (0.02 g) + Wheat barn (0.01 g) mixed) contents were used to perform 3, 6, 9, 12, 24 and 48 h incubation for in vitro fermentation. Ruminal pH values were ranged within normal ruminal microbial fermentation. Dry matter digestibility was not significantly different across the treatments during the whole fermentation time. Also, the result of microbial growth had no adversely effect on during the whole fermentation time. At 24 h, methane emission was significantly lower (P<0.05) than all treatments except to MRA-1. Especially, MRA-4 carbon dioxide emission was significantly lower (P<0.05) than control at 9, 24 and 48 h incubation. In addition MRA-4 propionate concentration was significantly higher (P<0.05) than control at 24 h incubation. The result of RT-PCR Ciliate-associated methanogens were significantly lower (P<0.05) at MRA-1, MRA-3 and MRA-4 than control at 24 h incubation. Based on the present results, MRA-4 could be suggestible methane emission inhibitor as a natural feed additive.
Waste management in Jeju Province, Korea, has recently emerged as an urgent problem. The increasing waste discharge requires more landfills but, since it is an island, the available land is restricted. Accordingly, an efficient waste management urgently requires environmentally sustainable policies. In this article, the waste discharge characteristics (such as the amount of waste, its composition, etc.) of Jeju Province have been compared with those in the rest of Korea. The current industrial waste management of two cities on the Island, Jeju City and Seogwipo City, has been also analyzed to suggest policies for an efficient management. The local government’s endeavor to enhance environmental awareness of the community has been known to reduce the private cost of policy compliance, and have individuals recognize the results of their policy compliance. Policies to achieve the above are then proposed.
Background: To enhance the taste and physiological characteristics of Lycii fructus (Gugija) extracts, we investigated the changes in the physiological characteristics of Gugija extracts caused by adding white ginseng (WG) and red ginseng (RG)
Methods and Results: Gugija extracts, including 10G10, 10GW-G8 : 2, -G6 : 4, -G4 : 6, -G2 : 8, and -G0 (mixtures made by replacing 0, 20, 40, 60, 80, and 100% of Gugija with WG), as well as 10G10, 10GR-G8 : 2, -G6 : 4, -G4 : 6, -G2 : 8, and -G0 (mixture made by replacing 0, 20, 40, 60, 80, and 100% of Gugija with RG) were extracted with water at 10 times the respective mixture's volume. The antioxidant activities of Gugija extracts were investigated by assessing their 1,1-diphenyl-2-picrydrazyl (DPPH) and 2,2’-azinobis(3ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, ferric reducing antioxidant potential (FRAP) activity, nitrite scavenging activity, and angiotensin converting enzyme (ACE) inhibitory activity. As the amount of WG added increased, the DPPH, and, ABTS radical scavenging activity, and FRAP activity of the Gugija extract decreased. The half maximal inhibitory concentration (IC50) value of 10G10, 10GW-G6 : 4, 10GR-G6 : 4, and 10GR-G0 for DPPH radical scavenging activity were 25.50 ± 1.04, 52.06 ± 1.46, 16.87 ± 1.24, and 9.50 ± 0.16 ㎕/㎖, respectively. On the other hand, the physiological activity of Gugija extract increased with the addition of increasing amounts of RG. However, ACE inhibitory activity was the highest (50.25 ± 2.58%) in the Gugija 10-fold extract without any added RG.
Conclusions: From the above results, we suggest that adding RG to Gugija extracts increase their antioxidant, FRAP, and nitrite scavenging activities.
Background : Polygonati rhizoma is used for medicine using rhizome of Polygonatum sibiricum Redoute belonging to Liliaceae. This study was carried out to select proper chemical for leaf spot disease control of P. sibiricum Redoute.
Methods and Results : In order to select proper chemical for leaf spot disease control of P. sibiricum Redoute, Alternaria sp. was isolated from leave of P. sibiricum Redoute and pathogenicity was verified. Control value was checked after application on leaves for 3 times in 6-years-old field in Geumsan and 5-years-old field in Jaecheon. Chemicals were applied in June and July for 3 times totally without any other chemicals application. At 10 days after final chemical application, 20 plants were checked for infected leaf ratio on 20 leaves placed in middle and upper point of stem. In Geumsan, control value was higher as 88.3% in Pyraclostrobin, 86.1% in Polyoxin B, 84.4% in Pyribencarb, 82.2% in Iminoctadine tris (albesilate). In Jaecheon, control value was higher as 88.1% in Pyraclostrobin, 87.1% in Pyraclostrobin, 86.3% in Pyribencarb, 83.0% in Iminoctadine tris (albesilate).
Conclusion : The result of this study on chemical selection for leaf spot disease control of P. sibiricum Redoute was as follows. Pyraclostrobin, Polyoxin B, Pyribencarb, and Iminoctadine tris (albesilate) showed excellent control value with over 80% and no damages. Above chemicals were considered excellent as chemicals for leaf spot disease in P. sibiricum Redoute.
Background : Insect pests damages are increasing on the field of Lycium chinense under organic farming management and especially, pest damage of Gelechiidae (Ilseopsis parki Povolny) is serious. Currently, various organic farming materials are registered, but insecticidal activity against Gelechiidae was not verified. Therefore, this experiment was carried out to screening for effective organic farming materials showing insecticidal activity in Gelechiidae.
Methods and Results : Screening for effective organic farming materials (OFM) showing insecticidal activity in Gelechiidae, we screening OFMs through in vitro testing Among them, OFMs showing insecticidal activity were first selected through field test. In the field test method, OFMs was sprayed at the time of moth occurrence, after 5 days of treatment, insecticidal activity was investigated as a result, a total of five OFMs were selected through the in vitro test and the Sophora japonica and three plant extracts showed the best control effect at 81.7%. in 2017. In 2018, the 2017 selected OFM and 4 kinds of new OFMs were field tested. The field test was performed in the same method as before. As a result, 2 kinds of OFMs made of Sophora japonica and three plant extracts extract and Sophora flavescens extract showed high control value of 87.3% and 88.3%, respectively. In contrast one organic agricultural material showed a chemical injury. To determine the timing of control, the extract was treated before and after topping and pretreatment of topping showed better control value by 80%.
Conclusion : Insecticidal activity against Gelechiidae was not effective in all tested OFMs, but the 2 OFMs showed a high control value of over 80%. In this study, we selected 2 materials out of 9 OFMs against Gelechiidae, and It was effective to treat OFM before topping.