• Title/Summary/Keyword: Ec

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Variation of OC and EC in PM2.5 at Mt. Taehwa (태화산 PM2.5 OC와 EC의 변화 특성)

  • Ham, Jeeyoung;Lee, Meehye;Kim, Hyun Seok;Park, Hyunju;Cho, Gangnam;Park, Jungmin
    • Journal of Korean Society for Atmospheric Environment
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    • v.32 no.1
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    • pp.21-31
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    • 2016
  • Organic carbon (OC) and elemental carbon (EC) in $PM_{2.5}$ were measured with Sunset OC/EC Field Analyzer at Taehwa Research Forest (TRF) near Seoul metropolitan area from May 2013 to April 2014. During the study period, the mean concentrations of OC and EC were $5.0{\pm}3.2{\mu}gC/m^3$ and $1.7{\pm}1.0{\mu}gC/m^3$, respectively. They showed clear seasonality reaching their maximum in winter ($6.5{\mu}gC/m^3$ and $1.9{\mu}gC/m^3$) and minimum in wet summer ($2.5{\mu}gC/m^3$ and $1.4{\mu}gC/m^3$). While OC showed greater seasonal variation, the diurnal variation was more noticeable for EC through all seasons with a clear maximum in the morning, which reveals the influence of vehicle emissions. In contrast, OC exhibited a broad second peak in the afternoon during May~June, when biological activities were the highest. Using the morning peaks of EC and OC, primary OC/EC ratio was assessed, which was assumed to be anthropogenic origin. It was the greatest in winter followed by spring and the lowest in wet summer. The seasonal difference in primary OC/EC ratio implies the influence of non-local sources of OC at the Mt. Taehwa.

Chemical Control of the Pine Gall Midges (Thecodiplosis japonensis Uchida et Inouye) VII. Improvement of the Trunk Implantation Methods of Systemic Insecticides (솔잎혹파리의 약제방제에 관한 연구 VII. 침투성 살충제의 수간주입방법 개선에 관한 연구)

  • Choi Seung-Yoon;Park Hyung-Man;Chung Bu-Ken
    • Korean journal of applied entomology
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    • v.21 no.4 s.53
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    • pp.191-194
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    • 1982
  • Using the two different trunk-implantation methods, the systemic insecticides omethoate $(Folimat^{(R)}\;50\;EC)$, vamidothion $(Kilval^{(R)}\;40\;EC)$, methamidophos $(Tamaron^{(R)}\;60\;SL)$, phosphamidon $(Dimecron^{(R)}\;50\;EC)$, monocrorotophos $(Nuvacron^{(R)}\;24\;EC)$, dimethoate $(Rogor^{(R)}\;50\;EC)$, and phosalone$(Rubitox^{(R)})$ were evaluated for the control of the pine gall midges(Thecodiplosis japonensis Uchida et Inouye). Except phosalone, all the insecticides tested in this experiment were very effective for the suppression of the gall incidence by the insects. There was no significant difference in effectiveness between the conventional drilling and improved Mauget methods, and trunk-implantation of the insecticides by the improved Mauget method seemed to be much more feasible in practical view points of the labor cost saving the recovery of the holes drilled.

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The Characteristics of Groundwater Quality in the Youngsan and Sumjin River Basins Using Geostatistical Methods (지구통계 기법을 이용한 영산강.섬진강 유역의 지하수 수질특성 연구)

  • 정상용;심병완;김규범;강동환;박희영
    • Journal of the Korean Society of Groundwater Environment
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    • v.7 no.3
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    • pp.125-132
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    • 2000
  • pH, EC and TDS are basic components in the investigation of groundwater quality, and are very important to the preliminary assessment of groundwater quality. These three chemical components investigated at the Youngsan and Sumjin river basins in 1998 suggest that the groundwater quality is generally good in these basins. Linear regression analysis shows that TDS versus EC has an linear correlation, but EC versus pH, and TDS versus pH have nearly no correlation. The relation of TDS and EC is 1.0 mg/1=1.52 $mu\textrm{S}$/cm, and it is the quality of natural water. In geostatistical analysis. three kinds of data are stationary random functions and they have exponential variograms. According to the isopleth maps of the groundwater quality, the groundwater quality of the Youngsan river basin is more contaminated than that of the Sumjin river basin. The isopleth maps of TDS and EC show very similar patterns because of the strong correlation between TDS and EC. The minimum and maximum values of the groundwater quality data are not reflected on the isopleth maps because kriging produces smooth distributions with minimum estimation variances.

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Anti-nociceptive and anti-inflammatory activities of the essential oil isolated from Cupressus arizonica Greene fruits

  • Fakhri, Sajad;Jafarian, Safoora;Majnooni, Mohammad Bagher;Farzaei, Mohammad Hosein;Mohammadi-Noori, Ehsan;Khan, Haroon
    • The Korean Journal of Pain
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    • v.35 no.1
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    • pp.33-42
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    • 2022
  • Background: Cupressus arizonica Greene is a coniferous tree with great importance in fragrance and pharmaceutical industries. Essential oils from C. arizonica (EC) have shown potential antioxidant, and anti-microbial activities. This study aimed at investigating the anti-nociceptive and anti-inflammatory effects/mechanisms of EC. Methods: The EC was evaluated for anti-nociceptive and anti-inflammatory activities on male Wistar rats using a formalin test and carrageenan-induced paw edema, respectively. Also, we pre-treated some of the animals with naloxone and flumazenil in the formalin test to find out the possible contributions of opioid and benzodiazepine receptors to EC anti-nociceptive effects. Finally, gas chromatography/mass spectrometry (GC/MS) analysis was used to identify the EC's constituents. Results: EC in intraperitoneal doses of 0.5 and 1 g/kg significantly decrease the nociceptive responses in both early and late phases of the formalin test. From a mechanistic point of view, flumazenil administration 20 minutes before the most effective dose of EC (1 g/kg) showed a meaningful reduction in the associated anti-nociceptive responses during the early and late phases of the formalin test. Naloxone also reduced the anti-nociceptive role of EC in the late phase. Furthermore, EC at the doses of 1, 0.5, and 0.25 g/kg significantly reduced paw edema from 0.5 hours after carrageenan injection to 4 hours. GC/MS analysis showed that isolated EC is a monoterpene-rich oil with the major presence of α-pinene (71.92%), myrcene (6.37%), δ-3-carene (4.68%), β-pinene (3.71%), and limonene (3.34%). Conclusions: EC showed potent anti-nociceptive and anti-inflammatory activities with the relative involvement of opioid and benzodiazepine receptors.

Relationship to the superficial radial nerve and anatomic variations of the first extensor compartment in Thai population: a basis for successful de Quervain tenosynovitis treatment

  • Krittameth Pasiphol;Sithiporn Agthong;Napatpong Thamrongskulsiri;Sirikorn Dokthien;Thanasil Huanmanop;Tanat Tabtieng;Vilai Chentanez
    • Anatomy and Cell Biology
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    • v.57 no.2
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    • pp.246-255
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    • 2024
  • Knowledge of the superficial radial nerve (SRN) relationship and anatomic variations of the first extensor compartment (1st EC) will contribute to a better outcome of de Quervain tenosynovitis treatment. We dissected 87 embalmed cadaveric wrists to determine the relationship of the SRN, the 1st EC length, distance from the proximal and distal 1st EC borders to radial styloid process (RSP), abductor pollicis longus (APL) and extensor pollicis brevis (EPB) tendon slip numbers, and the presence of septum. Our results revealed SRN crossing over the 1st EC in 59.5%. The lateral branch of the superficial radial nerve to the 1st EC midline in most cases (61.9%) except for one specimen, where lateral antebrachial cutaneous nerve was the closest. Distances from proximal and distal 1st EC borders to the RSP were 19.7±4.1 mm and 7.6±1.8 mm, respectively. Extensor retinaculum (ER) width over 1st EC (1st EC length) was 14.8±3.2 mm. Complete and incomplete septa were found in 17.2%, and 42.5%, respectively. The most frequent APL tendon slip number in the compartment was two in overall 47 specimens (54.0%). Almost all compartments (85 specimens; 97.7%) contained one EPB tendon slip. We detected bilateral EPB absence in one cadaver. Moreover, we recorded a tendon slip from extensor pollicis longus traveling into 1st EC bilaterally in one cadaver and observed the EPB muscle belly extension into 1st EC in 9 wrists. Awareness of 1st EC anatomic variations would be essential for successful surgical and nonsurgical outcomes.

An Empirical Research for the Critical Factors on International Market Entry in Electronic Commerce Industry (전자상거래 산업의 해외 진출 결정요인에 관한 실증적 연구)

  • 김정욱;홍성태;이동일
    • Journal of Korean Society for Quality Management
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    • v.29 no.3
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    • pp.18-38
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    • 2001
  • This paper attempts to identify variables which affect Korean electronic commerce(EC) venture's strategies for the international market entry decision making. Especially in the perspective of quality management perspective, it is highly relevant question which factors are critical when the industry has high technology driven characteristics such as EC, product quality related factors or environmental factors. Technology competence, operational competence, local marketing competence, psychological barriers, domestic competition level, and local infrastructure level are included to generate the explaining model for international market entry decision. The result is that the higher technology competence and local marketing competence are the significant factors. The higher the perception in these factors, the higher the intention to enter the international market in EC industry. These factors play a pivotal role in determining to go abroad the foreign EC market. Our finding implies that the subjective confidence on quality of EC solution(technology competence) and venture's capability of maintaining it(local marketing competence) are the important factors, when EC ventures make the decisions to enter the foreign markets.

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A Study on Korean Aviation and Tourism Policy in Relation to the EC and NAFTA Integration (EC 및 NAFTA 통합(統合)에 대비(對備)한 한국(韓國)의 항공관광산업정책(航空觀光産業政策) 연구(硏究))

  • Hong, Soon-Kil
    • The Korean Journal of Air & Space Law and Policy
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    • v.7
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    • pp.17-53
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    • 1995
  • The paper analyzes the impact of EC and NAFTA integration upon Korea and other 3rd countries and studies policies how to react against them particularly in the field of aviation and tourism industry. Chapter 2 introduces the contents of each step and process of EC integration in the field of aviation and tourism industry. Chapter 3 analyzes the contents of integration and cooperation of NAFTA in the field of aviation and tourism industry. Chapter 4 studies the regulation or deregulation policy of EC and NAFTA toward the industry of non-EC and non-NAFTA area. Chapter 5 surveys and analyzes about the policies and strategies of Japan, ASEAN and the 3rd countries. Finally, Chapter 6 analyzes the impact on Korean aviation and tourism industry and proposes some suggestions on the future policy of Korea independently or in association with the neighboring countries such as Japan and China against the integration of EC and NAFTA.

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Factors Influencing Business to Business Electronic Commerce (기업간 전자상거래 도입 결정요인)

  • 송윤희
    • The Journal of the Korea Contents Association
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    • v.2 no.3
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    • pp.41-58
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    • 2002
  • The purpose of this study was to examine the influence Of external environmental context, organizational context, and technical context on adoption and diffusion of B2B EC using innovation framework In this study, factors distinguishing non-adoption companies of B2B EC from adoption companies of B2B EC were customer-supplier power, perceived benefits, top management support, organizational strategy and organizational characteristics. The results of this research weight various B2B EC adoption factors in terms of their strategic importance.

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Rule-Based Cooperation of Distributed EC Systems

  • Lee, Dong-Woo
    • International Journal of Contents
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    • v.5 no.3
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    • pp.79-85
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    • 2009
  • Emergent requests or urgent information among enterprises require their intimate collaboration in B2B EC (electronic commerce). This paper analyzes the needs of intimate cooperation of distributed EC systems in terms of business contracts and presents an active rule-based methodology of close cooperation among EC systems and an active rule component to support it. Since the rule component provides high level rule patterns and event-based immediate processing, system administrators and programmers can easily program and maintain intimate cooperation of distributed EC systems independently to the application logic. The proposed active rule component facilitates HTTP protocol. Its prototype is implemented in B2B EC environment and evaluated using basic trigger facility of a commercial DBMS.

Propagation of Engineering Changes for Supporting Consistent Product Data View (일관된 제품자료관점을 지원하는 설계변경 전달에 관한 연구)

  • 도남철
    • Korean Journal of Computational Design and Engineering
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    • v.8 no.2
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    • pp.90-100
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    • 2003
  • Engineering change (EC) objects are the data structure and related operations that can support applications for EC procedures or processes. Their functionalities include controlling management data, specifying related product structure, and archiving a history of product structure changes for EC management. In this paper we introduce a systematic approach to support the propagation of changes between different product structure views using the history of structure changes in EC objects. The change propagations supported by EC objects enable designers to maintain the consistency of multiple product structure views for engineering, manufacturing or even customer support applications. This paper also includes EC examples and experimental implementations for the proposed EC objects.