In this study, the antimicrobial, antioxidant activities and α-glucosidase inhibitory activities of Amphidinium carterae ethanol extract (AE) was evaluated for using as a functional food ingredient. Chlorella ethanol extract (CE) was used to the comparison as a control. Anticancer activities of the AE and CE were analyzed by HepG2 and HT-29 human cancer cell. The AE showed antimicrobial activities for all tested bacterial strains. Whereas, CE showed antimicrobial activities for several tested bacterial strains only. The CE showed higher total phenolics contents, DPPH and ABTS radical-scavenging activities (47.36 mg/g, 22.42% and 28.58%, respectively) than those of AE (8.88 mg/g, 20.16% and 17.69%, respectively). AE showed anti-diabetic effect on α-glucosidase inhibitory activity with dose-dependantly manner. The cell viability of AE (125 μg/mL) on HepG2 and HT-29 human cancer cells were 38.12% and 11.27%, respectively. It was demonstrated that ethanol was efficient solvent for extracting functional components from A. carterae. These results indicated that AE can be described as a good candidate for using as a functional food ingredient.

수은 및 수은화합물의 배출로부터 국민의 건강 및 환경을 보호하기 위하여 국제수은협약(Minamata Convention on Mercury)이 채택되었다. 수은은 체내 비교적 미량이 노출되어도 생물체에 강한 독성을 나타낸다. 또한 수은으로 오염된 폐기물을 처리 및 처분하는 과정에서 수은이 환경으로 유출될 가능성이 존재하여 배출 규제 강화 및 관리에 관심이 집중되고 있다. 공정에서 배출되는 액상 수은 폐기물에는 용해된 수은 및 수은화합물과 고형물 형태의 것이 함유되어 있다. 따라서 폐기물의 특성에 적합한 수은의 제어가 필요하다. 본 연구에서는 국내 산업시설에서 공정부산물로 발생하는 액상 수은 폐기물을 처리하기 위하여, 총 ６단으로 구성된 흡착설비를 구축하였다. 1~2단계는 각각 10㎛, 5㎛입경의 섬유 필터(MICRO Filter)를 사용하였다. HgCl2는 타 수은화합물에 비하여 수용성이 크고 폐수에 잔류할 가능성이 높다. 따라서 3~5단계는 Cl2제거 효과가 있는 활성탄 필터(CTO Filter)를 사용하였다. 액상 수은 폐기물의 처리 용량을 평가하기 위해 시료의 투입 유량 60 L/hr, 90 L/hr 및 150 L/hr로 달리하여 실험을 진행하였다. MICRO 필터 및 활성탄 필터(CTO Filter)의 수은 제거 효율은 최종단계에서 각 유량별로 96%, 92%, 86%으로 확인되었다. 액상 폐기물 시료에서 수은 화합물을 제거하는데 사용된 필터의 수은 함유 농도를 분석한 결과, 30.3~61.8 mg-Hg/kg으로 분석되었다. 액상 폐기물 수은 제거를 위하여 사용된 필터는 수은 오염 폐기물로써 적정 처리가 필요하다. 시료에 함유된 수은 화합물의 특성에 적합한 필터의 개발 및 사용된 필터의 적정 처리 방법에 대한 연구가 필요하다.

Aeration with low energy micro-bubble generation and UV/H2O2 processes was introduced to verify the possibility of oxidation treatment for acid mine drainage. During 10 hours of aeration with micro-bubbles, Fe and As concentrations were decreased to 18.1 and 61.8%, respectively, while Cu, Cd, Al were kept at influent concentrations. Other heavy metals such as Mn, Cr, Pb, Zn, and Ni concentrations fluctuated due to the repetition of oxidation and release. Twenty days of aeration indicated the oxidation possibility for Cu, Cd, and Al. With the employment of UV/H2O2 processes, more than 77% of Cu and Fe removed, whereas slightly more than 30% of Cd and Al removed.

This paper presents the development of a 3D printer based piezo-driven vertical micro-positioning stage. The stage consists of two flexure bridge structures which amplify and transfer the horizontal motion of the piezo-element into vertical motion of the end-effector. The stage is fabricated with ABS material using a precision 3D printer. This enables a one-body design eliminating the need for assembly, and significantly increases the freedom in design while shortening fabrication time. The design of the stage was optimized using response surface analysis method. Experimental results are presented which demonstrate 100nm stepping in the vertical out-of-plane direction. The results demonstrate the future possibilities of applying 3D printers and ABS material in fabricating linear driven motion stages.

This study was aimed at determining the changes in heavy metal removal efficiency at different acid concentrations in a micro-nanobubble soil washing system and pickling process that is used to dispose of heavy metals. For this purpose, the initial and final heavy metal concentrations were measured to calculate the heavy metal removal efficiency 5, 10, 20, 30, 60, and 120 min into the experiment. Soil contaminated by heavy metals and extracted from 0~15 cm below the surface of a vehicle junkyard in the city of U was used in the experiment. The extracted soil was air-dried for 24 h, after which a No. 10 (2 mm) was used as a filter to remove large particles and other substances from the soil as well as to even out the samples. As for the operating conditions, the air inflow rate in the micro-nano bubble soil washing system was fixed at 2 L/min,; with the concentration of hydrogen peroxide being adjusted to 5%, 10%, or 15%. The treatment lasted 120 min. The results showed that when the concentration of hydrogen peroxide was 5%, the efficiency of Zn removal was 27.4%, whereas those of Ni and Pb were 28.7% and 22.8%, respectively. When the concentration of hydrogen peroxide was 10%, the efficiency of Zn removal was 38.7%, whereas those of Ni and Pb were 42.6% and 28.6%, respectively. When the concentration of hydrogen peroxide was 15%, the efficiency of Zn removal was 49.7%, whereas those of Ni and Pb were 57.1% and 42.6%, respectively. Therefore, the efficiency of removal of all three heavy metals was the highest when the hydrogen peroxide concentration was 15%.

Background : Ginseng rain cover farming is expanding around Jinan county and Jangsu country of North Jeolla Province. Some farmers doing ginseng rain cover farming have suffered from difficulties due to hot weather damages. However, it is a situation that the study on mitigation techniques for high temperature damage do not exist with ginseng rain cover farming. Methods and Results : The test covering work was firstly done on April 28th for heat block film+90% black light blocking net, blue double sided film, and PE film+75% black light blocking net and when it comes to second treatment, 30% and 40% shading were implemented for heat block film group and blue double sided film group respectively and 75% black light blocking net was installed on PE film+75% shading group. When it comes to micro-climate measurement in rain cover facility, temperature, humidity and light intensity were measured during the growing period of ginseng. The results are as follows. Regarding the light transmittance (per PAR, 10 am in clear day) in facility with 1st covering, light block film covered group (LBF), blue double sided film group (BDF) and PE film group have 12.9±1.8%, has 11.6±1.0% and 27.1±1.1% respectively and after 2nd covering, in LBF groups, 30% blocking, 40% blcoking and no blocking have 10.6±1.3%, 8.2±0.9% and 12.9±1.8% and in BDF groups, 30% blocking, 40% blcoking and no blocking have 9.4±0.8%, 7.9±0.7% and 11.6±1.0 respectively and PE film group has 10.6±0.7%. Relative humidity also showed the same trend as temperature. The average monthly amount of light and maximum light intensity were lower in 30% and 40% light blocking groups of LBF and BDF and a little higher in no light blocking group compared to PE film group. The degree of high temperature damage was 1 in no LBF of BDF, but no LBF of LBF was so bad like 3. However, there was no high temperature damage in the test groups of blocking films or BDF with 30% and 40% light blocked light screens. Regarding root weight, all secondly treated groups of LBF group and BDF group were lighter compared to 4.36g of PE film group and especially, prism sheetof no light blocking group has 2.5g and BDF of of no light blocking group has 3.21g. 30 % and 40% light blocking groups of LBF group and BDF group were light with 3.20~4.07g. Conclusion : Regarding the analysis result on micro-climate in facility with different cover materials for 2 years old ginseng in ginseng rain cover farming of Gyeonggi Province, the covering method suitable for high temperature damage mitigation in ginseng rain cover farming was that 1st covering was done by PE film+75% black light blocking net and then 75% black light blocking net is additionally covered at a time when outside temperatures reaches 30℃.

Purpose - Considering the importance of housing needs to real estate market, domestic studies on real estate prices from the perspective of demand are basically based on macro-data, but relatively few are associated with micro-data of urban real estate demand. We try to find a reliable relation of elasticity of demand and commercial housing market. Research design, data, and methodology - In this paper, we have derived housing demand theoretic method and have utilized micro-data of residential family housing survey of downtown area in Kunming City in October, 2015 to estimate income elasticity and price elasticity of housing demand respectively and make a comparative analysis. Results - The results indicate that income elasticity and price elasticity of families with owner-occupied housing are both larger than those of families with rental housing. Income elasticity of housing demand of urban residential families in Kunming is far below the foreign average and eastern coastal cities level, however, the corresponding price elasticity is far higher. Conclusions - We suggest that housing affordability of urban families in western China are constrained by the level of economic development, and the current housing price level has exceeded the economic affordability and psychological expectation of ordinary residents. Furthermore, noticing the great rigidity of housing demand, the expansion space of housing market for improvement and for commodity is limited.

Small and micro cultural enterprises make tremendous contributions to the development as well as the growth of China’s cultural industry. Creative talents who is playing a significant role are the sources of the rise, development and prosperity of enterprises. It is useful to develop a series of special strategies to motivate the creative talents on the premise that we analyzed the current situation of small and micro enterprises, the characteristics and demand factors of the creative talents. At present, there exist some problems in the small and micro enterprises about incentive, such as inferfect human resource management, low overall wage level and depressed business environment and so on. In order to solve the above problems, we ought to stick to the principles: combining the material and mental incentives, short-term and long-term incentives as well as individual and team motivation. We can complete the system of incentives by means of human resource outsourcing, create suitable environment for creative talents, enhance cultural and intrinsic incentives and so on intending to improve the incentive level of creative talents in small and micro enterprises.

The mechanism of micro-bubble generation with a pump is not clarified yet, so the design of water treatment systems with a micro-bubble generating pump is based on trial and error methods. This study tried to explain clearly quantitative relationships of experimental micro-bubble concentration (Cair) of continuous operation tests with a micro-bubble generating pump and theoretical air solubility. Operation parameters for the tests were discharge pressure (Pg), water (Qw0) and air (q0) flow rates, orifice diameter (DO), and retention time (t). The experimental micro-bubble concentrations (Cair) at 4.8 atm of discharge pressure (Pg) were in the range of 21.04 to 25.29 mL/L. When the retention time (t) by changing the pipe line length (LP) increased from 1.22 to 6.77s, the experimental micro-bubble concentrations (Cair) increased from 25.86 to 30.78 mL air/L water linearly. The dissolved and dispersed micro-bubble concentrations (Cair) are approximately 4 times more than the theoretical air solubility.

Background : Ginseng is a semi-shade plant which prefers cool temperature and mild lighting, and artificially installed shading facility is required from preventing photo-oxidation occurrence when ginseng is exposed to direct sunlight. High temperature damages are commonly noticed due to recent global warming although more farmers are using aluminum foil and blue light-proof screen instead of 4-layered polyethylene shade net (blue 3 + black 1) to prevent the rise in temperature and influx of rainwater, there are insufficient research conducted. Methods and Results : In mid-March, 2015, we have installed steel A type shading facility after transplanting 2-year-old domestic variety ginseng in 7 lines, 10 rows per 3.3㎡. We have prevented the excessive influx of direct light by fixing 4-layered shade net, aluminum foil and blue light-proof screen as shading materials on facilities and adding 2-layered black polyethylene shade net. During July and August with high temperature, light transmission rates have shown varying according to shading materials used: blue light-proof screen (8.4%) > aluminum foil (5.9%) > 4-layered shade net (3.3%). In case of the highest temperature reached, the order followed blue light-proof screen (42.3℃) > 4-layered shade net (40.8℃) > aluminum foil (38.3℃), and in case of average temperature it followed blue light-proof screen (48.7%) > 4-layered shade net (37.6%) > aluminum foil (33.2%). Although there were no difference about leaf area among the shading materials, ginseng leaf grown in aluminum foil has lower chlorophyll content than the other two treatment plot because of photooxidation by light damage. The 3-yr-old ginseng root weight harvested in end of October increased as follows light-proof screen (14.4g) > 4-layered shade net (11.9g) > aluminum foil (9.8g). Conclusion : Aluminum foil showed greater influx of light but lower temperature than 4-layered shade net due to its materialistic character. However the front side of foil can reflect light and cause photo-oxidation of rear-planted ginseng leaves, so it is a need for improvement. In case of blue light-proof screen, although it had higher inside temperature, the root weight of ginseng was the heaviest because of less influx of light and destruction of chlorophyll.

We analyzed the micro-meteorological characteristics during typical steam fog over the Gumi Reservoir of Nakdong river with the field observation data for recent 2 year(1 April 2013~31 March 2015) collected by the national institute of meteorological research, KMA. Steam fog occur when the cold drainage flows over the warm water surface. As the sensible and latent heat from water are provided to the air, the instability of lower atmosphere is increased. The resultant vertical mixing of warm, moist air near water surface and cold air aloft causes the formation of status cloud. The convection strengthened by radiative cooling of the upper part of the stratus causes the fog to propagate downward. Also, the temperature at the lowest atmosphere is increased rapidly and the inversion near surface disappear by these processes when the fog forms. The increase of wind speed is observed because the downward transportation of momentum is caused by vertical mixing.

전기화재의 주된 원인은 단락, 과부하·과전류, 누전 및 접촉 불량 사고로 크게 구분되고, 전기화재는 상기의 1차적인 원인보다는 이들 사고에서 동반되는 전기아크(electric arc)에 의한 주변 가연물질로 확대되는 2차적인 영향에 의한 화재가 대부분이다. 본 논문에서는 저압배선계통을 이용하는 가정이나 산업현장에서 주로 발생하는 전기화재의 주요 원인인 아크 사고를 감지하지 못하는 기존 과부하겸용 누전차단기(RCD)의 문제점을 해결하기 위하여, 첨단 마이크로프로세서를 이용한 고속 고정밀의 아크 펄스 사고 감지용 마이크로프로세서 제어기를 제안한다. 또한 아크 펄스 사고 시뮬레이터를 이용한 실측 특성분석을 통하여 그 성능을 입증하고자 한다. 제안한 마이크로프로세서 제어기는 구조와 제어알고리즘 기법이 간단하여 소형·경량으로 설계 및 제작이 가능하고, 이에 따른 제작비용 감소와 설치 방법이 간단한 장점을 가진다.

콘크리트의 배합에 있어서 포졸란 물질의 사용은 수화된 시멘트내의 칼슘 실리케이트 수화물을 증가시키고 미세 공극을 채워줌으로써 콘크리트의 투수성을 감소시킨다. 또한 콘크리트 내의 전체 염기량을 낮추어 알카리 골재반응에 의한 균열의 방지에도 효과가 있다. 본 연구에서는 포졸란 물질 중 반응성이 가장 우수한 나노실리카를 사용한 콘크리트 시멘트의 미세구조를 나노압입을 이용하여 분석할 것이다. 물질 표면의 경도를 측정하여 물질의 강도 및 강성을 파악하는 방법은 금속에 대하여 100여년간 수행되어 왔다. 콘크리트의 강도를 파악하는데 있어서도 슈미트 햄머를 이용하여 콘크리트의 표면경도를 측정하고 강도와 연관 짓는 방법이 널리 사용되고 있다. 나노압입 실험은 이러한 이론적인 배경을 바탕으로 나노 스케일의 압입 시험기를 사용하여 시멘트 페이스트를 구성하고 있는 미세구조의 기계적 특성을 파악하는 방법이다. 향후 콘크리트의 동결융해 실험, 알카리 골재 반응, 프리스트레스 강선과의 접착력 실험과 연계하여 균열에 대한 높은 내구성을 요구하는 콘크리트의 제작에 최적화된 나노실리카의 배합비를 산출하기 위한 기초연구로 사용될 것이다.

2014년 국내에서 발생한 리조트 붕괴사고와 환풍구 붕괴 사고는 대형 인명 피해를 가져왔으며, 이로 인해 구조물 상시 안전점검의 필요성이 더욱 부각되었다. 특히, 강 구조물의 연결부는 파괴에 취약하므로 더욱 철저한 안전 관리가 필요하다. 사용 중 구조물의 안전을 보장하기 위하여 구조물 부재와 연결부의 응력상태를 파악해야 하지만, 기존의 비파괴 검사방법으로는 부재의 사용 중 응력상태를 파악하기 어렵다. 강재의 압입실험으로 강재의 응력상태를 파악할 수 있으며, 나노스케일의 압입실험은 마이크로 단위의 흔적만을 남기므로 비파괴 검사의 방법으로 사용될 수 있을 것이다. 본 연구에서는 용접모재(Weld Metal, WM), 열영향부(Heat Affected Zone, HAZ), 모재(Base Metal, BM)로 구성된 용접 연결부의 미세구조의 구성성분비를 나노압입을 사용하여 측정하는 방법을 제안하였다. 광학현미경을 이용하여 분석된 미세구조 구성성분비와 결과를 비교하였고, 제안된 방법이 유효함을 확인하였다. 향후 연구결과를 바탕으로 구조용강재 용접연결부의 응력상태에 따른 미세구조 특성 변화를 파악할 수 있을 것이고, 용접 연결부의 건전성을 판단하는 진단기술로 확장될 수 있을 것이다.

The objective of this work was to treat complex mal-odor of food waste with micro-bubbles from enhanced wet scrubber system, where the pilot plant was operated. Micro bubbles from the enhanced reactor of venturi scrubber were successfully generated through the air atomizing process with high velocity more than 60 m/sec and played an important role in the removal of mal-odor. Mal-odor was effectively changed into the micro-bubble and treated with washing chemicals together. Through establishing two series connection of the reactors, 85.2 % removal efficiency of complex mal-odor was obtained in case of average 940 times of input air. 0.35 kg/hr of sulfuric acid, 0.188 kg/hr of sodium hydroxide and 0.043 kg/hr of hypochlorite were injected for chemical washing.

In recent years, a rapid growth in the population and urbanization led to an increasing industrial growth. The inadequate treated-wasted water from industry and various non-point sources causes significant negative effects on the stream water. For past few decades, extensive researches have been performed on water purification process. The purpose of this study is to investigate mechanical performance and water purification properties of porous concrete by using effective microorganisms through the site assessment test. The mechanical performance evaluation results showed that the increase void ration caused an decrease in the strength. The optimal mix rate was found to be 15% void rate From the site assessment, it was evaluated that the porous concrete improved the quality of the water and the purification ratios are 34.1 for SS, 14.6% for BOD, 34.9% for COD, 11.4% for T-N, and 12.6% for T-P. The porous concrete and the related purification technique can reduce the non-point pollution sources flowing into the river.

The goal of this study was to evaluate micro-bubble concentration (Cair) in water by air/water ratio (A/W ratio) with a micro-bubble generating pump. The estimation of micro-bubble concentration is based on the balance of inlet/outlet air and water flow rate. On net A/W ratio to be generated micro-bubble, we found that the obtained the Cair are shown as a function of discharge pressure (Pg) of the micro-bubble generating pump. The correlation of the Cair and the Pg(Cair =3.261Pg-1.754) was adequately described by the least square methods with a high correlation coefficient (r = 0.9459) and calculated values fit the experimental data quite well. The Cair was lower than theoretical dissolved air concentration (Caq) calculated by Henry’s law. The Cair for being operated the micro-bubble generating pump was 6.75 – 39.53 mL/L, however, we found that the optimum of the Cair to generate micro-bubble was the range from 10 to 12 mL/L.

A rapid and simple method for the quantitative determination of volatile fatty acids (VFAs; propionic acid, n-butyric acid, i-valeric acid and n-valeric acid) and indoles (phenol, p-cresol, 4-ethyl phenol, indole and skatole) in pig slurry and dog excrement using solid-phase micro-extraction (SPME) coupled to gas chromatography was evaluated. 50/30 ㎛ DVB/CAR/PDMS (Divinylbenzene/Carboxen/Polydimethylsiloxane) fiber was used to extract the target compounds in aqueous media. Sample amount and adsorption time was standardized for the routine analysis. Detection limits were from 0.11 to 0.15 ㎍/L for VFAs and from 0.12 to 0.28 ㎍/L for indoles and the correlations observed (R2) were 0.975～1.000. This method was applied to the pig slurry, fertilizer, compost and dog excrement. In nearly all cases, the indoles were detected in concentrations of higher than their limits of detection (DOLs). But the VFAs in swine manure were below their DOLs.

This research investigated the effects of adding micro fibers on the direct tensile behavior of ultra-high-performance hybrid-fiber-reinforced concrete (UHPHFRC) at high strain rates. Macro fiber was long smooth fiber (LS, Df=0.3mm, Lf=30mm) and micro fiber was short smooth fiber (SS, Df=0.2mm, Lf=13mm). The volume content of macro fibers was 1.0% and the volume content of micro fibers varied between 0.0 and 1.0%. The addition of micro fibers clearly increased the tensile strength of UHPHFRCs even at high strain rates.

In this paper, ultrasonic velocity(UV) test through OPC and Slag concrete is conducted considering porosity under compressive and tensile loading conditions. The test results show that up to 50% of compressive loading condition, UV a little increases and remarkably drops at peak load, however it fluctuates under the tensile loading condition because of the number of increase micro cracks in concrete specimens.