• Title/Summary/Keyword: EC Education

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EC or TDS as a Water Pollution Criteria in Water Education Program (물환경 체험 및 탐구 활동에서 수질오염지표로서 전기전도도(EC) 혹은 총용존고형물질(TDS)의 활용에 대한 고찰)

  • Ahn, Samyoung
    • Journal of Environmental Science International
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    • v.31 no.4
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    • pp.341-356
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    • 2022
  • Electrical Conductivity (EC) or Total Dissolved Solids (TDS) has been often used to evaluate the water quality in some water education program for children and youth. This study attempted to find out whether EC (or TDS) can be used as a water pollution criteria in water education program. To clarify it, we used the water analysis data of July 2019 and January 2020 from Water Environment Information System. Data from 332 points in Han-river were used to investigate correlation between the parameters, such as BOD, COD, TN, TP vs EC. Correlation(r) for all data of BOD vs. EC was 0.347 for July 2019 and 0.483 for January 2020. No correlation was observed for BOD Ia and BOD Ib for July 2019 (r=-0.041, -0.030, respectively) and BOD Ia for January 2020 (r=0.041). Better correlation for all data of COD vs. EC was obtained (r=0.543 for July 2019 and r=0.610 for January 2020). However, no correlation was observed for COD Ia for January 2020. High vlaue of EC or TDS does not always mean water pollution, especially for clean water environment. Thus, EC (or TDS) alone can not be used as a water pollution criteria.

The Level of EC Utilization and its Impact on Firm Performance in SMEs

  • Jun, Byoung-Ho
    • Journal of Information Technology Applications and Management
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    • v.15 no.3
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    • pp.127-152
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    • 2008
  • This study sought to explore how SMEs are utilizing EC. Drawing on existing research on IT and EC related field, this study presented the framework of EC utilization level and analyzed its affecting factors in the point of organizational perspectives; strategy and competency. The impact of EC utilization on firm performance was also examined by employing BSC. Structural equation model was applied to test the relationships among the theoretical constructs with data from 171 SMEs. The results showed that the rate of EC utilization in SMEs is growing quite rapidly. However, manufacturing related firms still remain at a lower level compared to service related firms. As for the two affecting factors of EC utilization level, it was found that the level of EC utilization appeared to be driven not by strategy but by competency. This result implicates that EC utilization in SMEs doesn't reach to strategic purpose yet, while it is dependent on firm's competency. As far as the impact of EC utilization on firm performance, the study showed that the level of EC utilization has significant relationship with all perspectives performance indicators of BSC. This study can provide the managers with current EC utilization pattern and the guidelines as to where to put the efforts in the EC utilization and how to get an effective EC utilization strategy in the future.

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Electrochemical dehalogenation of disinfection by-products and iodine-containing contrast media: A review

  • Korshin, Gregory;Yan, Mingquan
    • Environmental Engineering Research
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    • v.23 no.4
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    • pp.345-353
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    • 2018
  • This paper summarizes results of research on the electrochemical (EC) degradation of disinfection by-products (DBPs) and iodine-containing contrast media (ICMs), with the focus on EC reductive dehalogenation. The efficiency of EC dehalogenation of DBPs increases with the number of halogen atoms in an individual DBP species. EC reductive cleavage of bromine from parent DBPs is faster than that of chlorine. EC data and quantum chemical modeling indicate that the EC reduction of iodine-containing DBPs (I-DBPs) is characterized by the formation of active iodine that reacts with the organic substrate. The occurrence of ICMs has attracted attention due to their association with the generation of I-DBPs. Indirect EC oxidation of ICMs using anodes that produce reactive oxygen species can result in a complete degradation of these compounds yet I-DBPs are formed in the process. Reductive EC deiodination of ICMs is rapid and its overall rate is diffusion-controlled yet I-DBPs are also produced in this reaction. Further progress in practically feasible EC methods to remove DBPs, ICMs and other trace-level organic contaminants requires the development of novel electrocatalytic materials, elimination of mass transfer limitations via innovative design of 3D electrodes and EC reactors, and further progress in the understanding of intrinsic mechanisms of EC reactions of DBPs and TrOC at EC interfaces.

Sperm-Associated Antigen 9 is a Promising marker for Early Diagnosis of Endometrial Cancer

  • Baser, Eralp;Togrul, Cihan;Ozgu, Emre;Ayhan, Sevgi;Caglar, Mete;Erkaya, Salim;Gungor, Tayfun
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.12
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    • pp.7635-7638
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    • 2013
  • Background: Sperm-associated antigen 9 (SPAG9) has been recently proposed as a novel biomarker for early diagnosis of several human tumors, including ovarian, cervical and breast cancers. Its clinical value remains to be clarified for endometrial cancer (EC). In this study, we investigated the utility of serum SPAG9 levels in diagnosis of EC and its association with important clinicopathological parameters. Materials and Methods: This cross-sectional study was performed at a tertiary women's referral center in Ankara, Turkey. Preoperative serum samples were collected from patients surgically treated for endometrial cancer between June 2012-April 2013. Similar aged women with a biopsy proven benign endometrium were used as controls. Serum SPAG9 levels were measured with an enzyme-linked immunosorbent assay (ELISA) method and assessed for links with clinicopathological factors. Receiver operating characteristic (ROC) curve analysis was performed to assess power of SPAG9 levels for EC prediction. P values less than 0.05 were considered statistically significant. Results: A total of 63 women with EC and 27 with benign endometrium were included in the study. Mean age in the EC group was $58.7{\pm}1.1$. Median SPAG9 levels in the EC and control groups were 18.3 (range, 12.7-53.8) and 14.1 (range, 4.3-65.3), respectively (p<0.001). A cut-off value of 17 ng/ml for SPAG9 predicted presence of malignant endometrium with 74% sensitivity and 83% specificity [Area under curve (AUC)=0.82, p<0.001]. SPAG9 levels did not demonstrate any significant association with histological type, FIGO stage, tumor grade, size, myometrial invasion, lymphovascular space invasion, cervical involvement, adnexal involvement, peritoneal cytology or lymph node status (all p>0.05). Conclusions: Testing for SPAG9 may be useful for early detection of EC in asymptomatic high-risk women. Its role in post-treatment follow-up and early detection of recurrence should be assessed in future trials.

Fabrication of SnO2-based All-solid-state Transmittance Variation Devices (SnO2 기반 고체상의 투과도 가변 소자 제조)

  • Shin, Dongkyun;Seo, Yuseok;Lee, Jinyoung;Park, Jongwoon
    • Journal of the Semiconductor & Display Technology
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    • v.19 no.3
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    • pp.23-29
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    • 2020
  • Electrochromic (EC) device is an element whose transmittance is changed by electrical energy. Coloring and decoloring states can be easily controlled and thus used in buildings and automobiles for energy saving. There exist several types of EC devices; EC using electrolytes, polymer dispersed liquid crystal (PDLC), and suspended particle device (SPD) using polarized molecules. However, these devices involve solutions such as electrolytes and liquid crystals, limiting their applications in high temperature environments. In this study, we have studied all-solid-state EC device based on Tin(IV) oxide (SnO2). A coloring phase is achieved when electrons are accumulated in the ultraviolet (UV)-treated SnO2 layer, whereas a decoloring mode is obtained when electrons are empty there. The UV treatment of SnO2 layer brings in a number of localized states in the bandgap, which traps electrons near the conduction band. The SnO2-based EC device shows a transmittance of 70.7% in the decoloring mode and 41% in the coloring mode at a voltage of 2.5 V. We have achieved a transmittance change as large as 29.7% at the wavelength of 550 nm. It also exhibits fast and stable driving characteristics, which have been demonstrated by the cyclic experiments of coloration and decoloration. It has also showed the memory effects induced by the insulating layer of titanium dioxide (TiO2) and silicone (Si).

The Design of EC-Business Server to Support the Internet Marketting for small and Medium Enterprises (기계분야 중소기업 마켓팅 지원 EC 서버 설계)

  • Kim, Yong-Ho;Jeon, Chang-Bae;Jeon, Hyeong-Deok
    • 연구논문집
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    • s.28
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    • pp.173-182
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    • 1998
  • We, ICOMM(Information Center Of Machinery & Materials), make efforts to apply the EC to support the Internet Marketing for Small and Medium Enterprises, and at the base of experience are carrying out diffusing the internet minds, applying the CALS, searching the internet information, education for internet and supporting the EC-hosting to count of first importance for 6,000 Manufacturing Industries located in KYOUNGNAM. Traditional Business-to-Business depends on the EDI by using VAN. As the Internet is lively and the Internet users incredibly increasing, the total marketing strategies of Enterprises are cyberized, and Enterprises try finding the new business partner by using Internet technologies, At the base of this Environments, this paper proposes the Internet Marketing Server (that is called EC-Business Server) that consists of the staging server to establish the Mall, the search engine for resembled manufactured goods, and so on. EC-Business Server supports Business-to-Business as in electronic commerce.

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The Strategies of Logistics Management for SMEs through CALS/EC (중소기업 물류경영 정보화를 위한 CALS/EC 전략)

  • Kim, Chang-Gyun
    • International Commerce and Information Review
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    • v.1 no.1
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    • pp.179-201
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    • 1999
  • CALS/EC is about doing business electronically. It is based on the electronic processing and transmission of data, including text, sound and video. It encompasses many diverse activities including electronic trading of goods and services, online delivery of digital content, electronic fund transfers, electronic share trading, electronic bills of lading, commercial auctions, collaborative design and engineering, online sourcing, public procuremet, direct consumer marketing, and after-sales service. It involves both products(e.g. consumer goods, specialised medical equipment) and services(e.g. information services, financial and legal services); traditional activities(e.g. healthcare, education) and new activities (e.g. virtual malls). CALS/EC will be emerging to replace and substitute the role of the conventional market. By changing and eliminating some processes of the transactions, the electronic market and the electronic commerce will redistribute the power and hence the benefits of the market activities. Traditional way of doing business may enter into the new electronic market because the role and function of trust and established reputation will be reinforced in the electronic market. The CALS/EC through the Internet has been in the spotlight in the shopping behavior of the consumers. Accordingly Corporates are trying to adapt themselves to those rapidly changing environments being affected by the Internet. Among others, particularly to be noted is the CALS/EC between corporations and consumers whose potential growth can be considered very substantial. This report, focusing on the introduction of CALS/EC for the logistics of SMEs, will allow us to prepare more efficiently for the coming 21st Century. It is obvious that CALS/EC is fast becoming the useful way of exchanging not only information but products in business between firm-to-firm and firm-to-customer.

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Vitellogenin Induction and Histo-metabolic Changes Following Exposure of Cyprinus carpio to Methyl Paraben

  • Barse, A.V.;Chakrabarti, T.;Ghosh, T.K.;Pal, A.K.;Kumar, Neeraj;Raman, R.P.;Jadhao, S.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.12
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    • pp.1557-1565
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    • 2010
  • Methyl paraben (MP), which is used as a preservative in pharmaceutical and cosmetic (shampoo) products, foods and beverages, enters into the aquatic environment and can pose a potential fish health hazard. In this experiment, effects of MP were evaluated in adult male common carp (Cyprinus carpio) by exposing them to fractions (1/$143^{rd}$ to 1/29th) of the $LC_{50}$ dose with every change of water for 28 days. Vitellogenin induction, metabolic enzymes, somatic indices and bioaccumulation were studied at weekly intervals. The $96^{th}$ h $LC_{50}$ of MP in fingerlings was 120 mg/L. Compared to the control, except for increases (p<0.01) in alkaline phosphatase (EC 3.1.3.1), alanine aminotransferase (EC 2.6.1.2) and liver size, there were decreases (p<0.01) in activity of acid phosphatase (EC 3.1.3.2), aspartate aminotransferase (EC 2.6.1.1), and testiculosomatic index following exposure to any dose of MP. Vitellogenin induction was significantly higher (p<0.01) in exposed than unexposed (control) fish. The bioaccumulation of MP in testis, liver, brain, gills and muscle tissues of fish increased significantly (p<0.01) with increase of dose from 0.84 ppm to 1.68 ppm. Dose and duration of exposure (p<0.01) indicated that an exposure period of 1 to 2 weeks was sufficient to cause changes in the quantifiable parameters studied. Fish exposed to 4.2 ppm MP became lethargic after the $26^{th}$ d. Histologically, degeneration, vacuolization and focal necrotic changes in liver and fibrosis-like changes in testicular tissue were noted.

Viologen Based All-in-one Flexible Electrochromic Devices (바이올로진 기반의 일체형 유연 전기변색소자)

  • Park, Bo-Seong;Kim, Hyun-Jeong;Shin, Hyeonho;Park, Seongmin;Lee, Jaeun;Jeon, Sunggun;Nah, Yoon-Chae
    • Korean Journal of Materials Research
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    • v.31 no.3
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    • pp.132-138
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    • 2021
  • Electrochromic devices (ECDs) have been drawing great attention due to their high color contrast, low power consumption, and memory effect, and can be used in smart windows, automatic dimming mirrors, and information display devices. As with other electronic devices such as LEDs (light emitting diodes), solar cells, and transistors, the mechanical flexibility of ECDs is one of the most important issue for their potential applications. In this paper, we report on flexible ECDs (f-ECDs) fabricated using an all-in-one EC gel, which is a mixture of electrolyte and EC material. The f-ECDs are compared with rigid ECDs (r-ECDs) on ITO glass substrate in terms of color contrast, coloration efficiency, and switching speed. It is confirmed that the f-ECDs embedding all-in-one gel show strong blue absorption and have competitive EC performance. Repetitive bending tests show a degradation of electrochromic performance, which must be improved using an optimized device fabrication process.

A Study on Curriculum and an Academic Classification Standard of Electronic Commerce Research (전자상거래학의 학문적 분류기준과 교과과정에 관한 연구)

  • 서순모;이종호
    • The Journal of Society for e-Business Studies
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    • v.8 no.3
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    • pp.143-164
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    • 2003
  • Because of the wide scale in EC area, the use of Electronic Commerce spreads out quickly. This paper proposes the curriculum applied to the department of EC in University reflecting the recent social trend. EC has some relations with the several areas like Computer Science & Engineering, Management and Industrial Engineering etc. after analyzing the domestic curriculums, we propose the propriate curriculums and academic classification standard. Also according to the standard, We want to propose the separate curriculums to three important majors and describe the introduction to each major.

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