• 제목/요약/키워드: Attention Concentration

검색결과 628건 처리시간 0.029초

하수역학 구축을 위한 시료 전처리 기술과 신속검출기술 (Pretreatment and Rapid Detection Methods for Wastewater-Based Epidemiology)

  • 이재엽;이복진;제스민아터;안창혁;김일호
    • 한국물환경학회지
    • /
    • 제39권1호
    • /
    • pp.102-110
    • /
    • 2023
  • Wastewater Based Epidemiology (WBE) provides useful information not only on the use of illegal drugs in the community, but also on the presence of hygiene and health products and infectious pathogens in sewage facilities. As a consequence of the SARS-CoV-19 virus epidemic in 2019, monitoring the status of the infection is of utmost importance. SARS-CoV-19 was also detected in sewage, and the number and trend of infections in the community suggest that the application of the WBE system would be useful and appropriate. This study introduces a pre-treatment concentration method including viruses in sewage samples. A total of seven methods which were subdivided into methods for adsorption-extraction, ultra-filtration, PEG precipitation, and ultra-centrifugation, and the results for analyzing the recovery rates were included. Meanwhile, it is necessary to pay attention to rapid detection technologies which analyze infectious pathogens at the site of sewage facilities. These can include ELISA, FTIR, SERS, and biosensor based on the detection principle, and the characteristics, advantages, and disadvantages of each were summarized herein. If rapid detection technologies and accurate quantitative analyses are further developed, the use of sewage mechanics in response to pandemic viruses is expected to expand further.

Zigbee 통신을 활용한 산업현장의 스마트 안전관리 시스템 (Smart Safety Management System of Industrial Site using Zigbee Communication)

  • 민지현;정가영;하현동;황인태;김남호
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국정보통신학회 2022년도 춘계학술대회
    • /
    • pp.546-549
    • /
    • 2022
  • 최근 산업 현장에서 발생하는 사고의 증가를 막기 위해 4차 산업 시대의 다양한 혁신 기술을 건축 행정에 접목하여 산업 현장 안전 관리의 효율성을 높이는 안전 관리 고도화 작업을 추진하고 있다. 이에 따라 산업 현장에서 발생하는 위험을 선제적으로 예방하고 실시간으로 관리하는 지능형 모니터링을 이용한 스마트 안전 관리 시스템이 주목받고 있다. 스마트 안전 관리 시스템은 곳곳에 위치된 센서를 통해 현장의 소음, 가스 농도, 미세먼지 농도, 건축 자재의 품질, 건축물의 기울기 그리고 RFID를 활용한 근무자의 출입 여부와 같은 요소를 실시간으로 원격 모니터링할 수 있는 시스템을 사용자에게 제공한다. 본 논문에서는 라즈베리파이를 이용하여 스마트 안전 관리 시스템을 위한 다양한 데이터를 지그비 통신으로 수집 및 모니터링하는 방법을 제시한다.

  • PDF

CORPORATE GOVERNANCE PRACTICE OF TAIWAN LISTED CONSTRUCTION COMPANIES AND ITS CORRELATION WITH INDUSTRIAL FEATURES

  • Hui-Yu Chou
    • 국제학술발표논문집
    • /
    • The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
    • /
    • pp.413-419
    • /
    • 2011
  • Corporate governance is a system articulating the division of responsibilities among different company members, and defining the running rules and procedures for making decisions on corporate affairs. The separation of ownership and management in modern enterprises brings agency problems to the company shareholders, and it is wildly believed that good practice on corporate governance is essential to prevent managers from taking actions by which profiteering their own benefits but compromising the interests of shareholders. This research investigates the level of companies' compliance with the corporate governance codes to find whether significant differences in corporate governance practice exist between the listed construction companies and the national leading companies in Taiwan. Further exploration focuses on the correlation between the compliance level and the industrial features. The investigation finds that: (1)Construction companies display lower levels of corporate governance compliance; (2)Construction companies display lower levels of structural board independence and respect for stakeholders; (3)Compliance levels of construction companies are correlated with the number of employees and the ownership concentration; (4)Compliance levels of the whole sample companies are correlated with the factors representing firm size, such as turnover, capital and number of employees, but are independent of profitability as well as stock price volatility. The above empirical evidence characterizes the features of corporate governance in Taiwan listed construction companies, including: (1)Large companies lurking high risk of agency problems have more willingness to conduct corporate governance and meanwhile can afford higher costs for the conduction, so that their compliance level would be higher than smaller companies; (2)Construction companies in Taiwan have higher ownership concentration, on account of the industrial tradition of family business, and therefore pay less attention to the compliance with structural board independence and respect for stakeholders. However, the conclusions indicate that further studies are essential to clarify whether the above disparities would lead to a negative cycle of corporate governance practice in construction industry. The benefits of corporate governance should unfold more evidently to convince construction companies for improving their investment environment and stimulating their healthy growth.

  • PDF

Residual characteristics and safety assessments of prochloraz and its metabolites in Aster yomena using QuEChERS and LC-MS/MS

  • Hyeon-Jin Lim;Young-Shin Kim;Chi-Hwan Lim
    • 농업과학연구
    • /
    • 제51권2호
    • /
    • pp.205-216
    • /
    • 2024
  • Although Aster yomena has recently attracted attention for its potential anti-cancer, antimicrobial, and immune-boosting effects, there are concerns about residual pesticides because they are consumed in salad-like forms. This study investigated residual characteristics and human dietary risks of the imidazole fungicide prochloraz applied to the herbal medicine Aster yomena with different spray frequency and timing. Residual analysis of prochloraz and its three main metabolites (BTS44595, BTS44596, and 2,4,6-trichlorophenol) in Aster yomena samples was performed using the QuEChERS method and LC-MS/MS. Mean recovery rates of the fungicide and its metabolites were satisfactory in the range of 80.1 ± 1.2% to 108.2 ± 3.8%. The residual concentration of the fungicide calculated as the sum of prochloraz and its metabolites was the highest (4.14 mg·kg-1) in the Aster yomena sample applied three times at weekly intervals with the fungicide until immediately before harvest. The fungicide residue concentration in the Aster yomena was below the method-limit of quantification (MLOQ) when it was applied twice at the interval of 9 day until 21 days before harvest. The theoretical maximum daily intake of prochloraz, calculated based on the daily intake of Aster yomena, mean adult body weight, and the highest residue level analyzed in the this study, was safe at < 80% of the acceptable daily intake of the fungicide (0.01 mg-1·kg·bw-1·day). In conclusion, the triple application method with prochloraz at weekly intervals until the harvest day is recommended to produce safe Aster yomena from the fungicide residues and risks to humans.

Effect of Temporary Loading of Nonylphenol on a Summer Planktonic Community in a Eutrophic Pond

  • Baek, Seung-Ho;Katano, Toshiya;Han, Myung-Soo
    • 생태와환경
    • /
    • 제41권4호
    • /
    • pp.519-529
    • /
    • 2008
  • Recent studies reveal one of the representative endocrine disrupters of nonylphenol affects on the composition of a planktonic community. Since nonylphenol is sometimes discharged into eutrophic waters, we monitored planktonic community composition of a eutrophic pond after receiving nonylphenol when cyanobacterium Microcystis aeruginosa mainly dominated. The experiment was carried out two times using small-scale microcosms in a laboratory. In both two experiments, ciliate abundances significantly decreased when nonylphenol was added. On the seventh day, the ciliate abundances in $10{\mu}g\;L^{-1}$ added treatments decreased by 36.9% in the first experiment and 33.6% in the second, when compared to the control. The response of other planktonic groups was less obvious to nonylphenol addition. In particular, in the first experiment, Chl. b/Chl. $\alpha$ and Chl. c/Chl. $\alpha$ significantly increased with the addition of nonylphenol, while total Chl. $\alpha$ concentration did not change. Indeed, bacillariophyceae and chlorophyceae abundances tended to increase with nonylphenol dosing. From these results, we tentatively hypothesized that nonylphenolloading positively affects on abundances of edible phytoplankton such as Scenedesmus spp. and diatoms by releasing from grazing pressure due to decrease in ciliate abundances. The present study emphasizes that the indirect effect of endocrine disrupters should be paid more attention when freshwater resources are polluted by them.

다공성 PLGA 마이크로입자 제조법의 최적화 연구 (Preparation of Highly Porous Poly(d,l-lactic-co-glycolic acid) (PLGA) Microspheres)

  • 박홍일;김현욱;이은성;이강춘;윤유석
    • Journal of Pharmaceutical Investigation
    • /
    • 제39권3호
    • /
    • pp.167-171
    • /
    • 2009
  • Poly(lactic-co-glycolic acid) (PLGA) microspheres have been a useful tool as a controlled drug delivery system for peptides and proteins. Recently, porous microspheres have gained great attention as inhalation drug delivery system due to their low aerodynamic densities. Here, we report highly porous PLGA microspheres, which were prepared by using a single o/w emulsification/solvent evaporation method. Two types of porogen, i.e., (i) extractable Pluronic F127 and (ii) gas foaming salt of ammonium bicarbonate, were used to induce pores on the surface of PLGA microspheres. The respective preparation conditions on dp/cp ratio and porogen concentration were determined by the previous preliminary experiments, and other preparation factors were further optimized on the basis of PLGA Mw and porogen type. The morphological features examined by scanning electron microscope (SEM) show these porous microspheres have highly porous surface structure with a diameter range of 20${\sim}$30 ${\mu}$m. These highly porous PLGA microspheres, which have much lower density, would be a practical aerosol system for pulmonary drug delivery.

산후조리원 내 신생아실의 실내 환경 특성 - 목재가구류에 따른 실내공기질과 조명배치에 따른 조도 특성을 중심으로 - (Indoor Environment of Infant Units in Postnatal Care Center - Focus on Indoor Air Quality by Types of Wooden Furniture and Intensity of Illumination by Arrangement of Lights -)

  • 정소담;김태욱;장슬애;김석환;이상진
    • 한국가구학회지
    • /
    • 제24권1호
    • /
    • pp.33-41
    • /
    • 2013
  • As professional postnatal care systems have been rapidly supplied, there is sharp increase of postnatal care centers without legal regulations for a mother and a infant. For the quick recovery of mothers, newborn infants that have weaker immune systems are being managed in group in the postnatal care centers. Recently, the attention of the postnatal care centers has been growing because the problem of pneumonia which led to result in a casuality in a infant unit was happen. So, this research analyzed the indoor environment of infant unit through measuring formaldehyde, carbon dioxide, intensity of illumination. As a result of the data, infant units showed higher concentration of formaldehyde and carbon dioxide than Indoor Air Quality Control Law. Moreover, infant units was measured higher intensity of illumination than the range of optimum illumination for infants.

  • PDF

Improvement of Electrical Conductivity of Transparent Conductive Single-Walled Carbon Nanotube Films Fabricated by Surfactant Dispersion

  • Lee, Seung-Ho;Kim, Myoung-Su;Goak, Jeung-Choon;Lee, Nae-Sung
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2009년도 추계학술대회 논문집
    • /
    • pp.17-17
    • /
    • 2009
  • Single-walled carbon nanotubes (SWCNTs) have attracted much attention as promising materials for transparent conducting films (TCFs), thanks to their superior electrical conductivity, high mechanical strength, and complete flexibility. The CNT-based TCFs can be used in a variety of application fields as flexible, transparent electrodes, including touch panel screens, flexible electronics, transparent heaters, etc. First of all, this study investigated the effect of a variety of surfactants on the dispersion of SWCNTs in an aqueous solution. Following the optimization of the dispersion by surfactants, flexible TCFs were fabricated by spraying the CNT suspension onto poly(ethylene terephthalate) (PET) substrates. The sheet resistances of the TCFs having different surfactants were investigated with treatment in nitric acid ($HNO_3$) whose concentration and period of treatment time were varied. It seems that the $HNO_3$ removes the surfactants from and is simultaneously doped into the SWCNT network, reducing the contact resistance between CNTs. TCFs were characterized by UV-VIS spectroscopy, thermogravimetric analyzer (TGA), scanning electron microscopy (SEM), and four-point probe.

  • PDF

탄산화가 진행된 기존 RC구조물의 표면보수공법 적용 후 FDM 해석을 이용한 탄산화 진행 예측 연구 (A Study on Predicting Progress Carbonation using FDM Analysis After Carbonated RC Structures Surface Repair)

  • 이형민;이한승;김영관
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2015년도 추계 학술논문 발표대회
    • /
    • pp.13-14
    • /
    • 2015
  • Carbonation is the results of the interaction of carbon dioxide gas in the atmosphere with the alkaline hydroxides in the concrete. in other words, of the hydrates in the cement pastes, the one which reacts with readily is Ca(OH)2, the product of the reaction being CaCO3 and which decreases the alkalinity of concrete. Consequently, RC structure is deteriorated due to steel corrosion in concrete. As the importance of maintenance of reinforced concrete structure recently has emerged, the attention of durability of structure has been increasing. There are many studies about durability decline especially due to the carbonation. In order to study carbonation progress after surface repair of carbonated concrete, each carbonation penetration velocity from different repair materials of concrete structure is compared through the experiment of carbonation accelerating CO2 concentration to 100%. As carbonation infiltration progress is predicted through this study, the counterplan of service life evaluation will be prepared on selection of repair materials of concrete structure.

  • PDF

부드러운 조각을 활용한 의상디자인 연구 -케이트 맥과이어의 작품을 중심으로- (A Study on the Fashion Design Using Soft Sculpture -Centered on Kate MccGwire's Works-)

  • 백진영;박주희
    • 한국의류학회지
    • /
    • 제42권2호
    • /
    • pp.251-268
    • /
    • 2018
  • This study suggests a fashion design using aesthetic characteristics of works by Kate MccGwire, a modern sculptor paying attention to soft sculpture materials such as feathers. In this research on MccGwire works, their internal meanings may be derived as the dualism of familiarity, movement and consciousness. Works also have aesthetic characteristics of overlapping, fluidity and twist. Using such characteristics, 4 one piece dresses and 2 vest dresses were made. Research findings are as follows. First, aesthetic characteristics of MccGwire works could be expanded into expressive areas of silhouettes and details in fashion. Second, visual flow and concentration could be expressed by gradual coloration of feather colors. Third, dart manipulation could be applied naturally by details and curve silhouettes of fashion design. Fourth, touch of feather material could be expressed fully by leaving the edge of garments raw. Fifth, spatiality of fashion could be implemented partially by applying decorative saddle stitching to costume design details. This study explored a potential of soft sculpture occurred during a transitional process of objet pursued by 20th century's avant-garde artists applicable to fashion design ideas that suggested methods for contemporary creative design.