• 한국표면공학회지
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• 제36권4호
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• pp.307-316
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• 2003

Salt spray, CASS(copper accelerated acetic salt spray) and EC(electrolytic corrosion) tests were performed in order to evaluate the corrosion resistance of plated Ni and Ni-Cr layers on Fe substrate. Compared with the conventional methods such as salt spray and CASS, the electrochemical method such as EC test may be beneficial in terms of test time span and quantitative accuracy. Furthermore, EC test can also become the alternative method to evaluate the resistance to corrosion of coatings by measuring the corrosion potentials of the coated layers in the electrolyte during the off-time of EC cycles. Compared with the corrosion potentials of pure iron, nickel, chromium, those potentials of coated layers can be used to anticipate the extent of corrosion. Results showed that in terms of the test time span, EC test gave 14 times and 21 times faster results than the salt spray test in cases of $5\mu\textrm{m}$ Ni and $20\mu\textrm{m}$ Ni plated layers, respectively. In addition, EC test also offered the shorter test time span than CASS test in cases of $5 \mu\textrm{m}$ Ni + $0.5\mu\textrm{m}$ Cr, and $20\mu\textrm{m}$ Ni + $0.5\mu\textrm{m}$ Cr on Fe substrate by 78 times and 182 times, respectively. Therefore, EC test can be regarded as the better method to evaluate the resistance to corrosion of coated layers than the conventional methods such as salt spray and CASS.

• 한국식품영양과학회지
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• 제29권3호
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• pp.543-548
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• 2000

EC-2B와 EC-2C 획분은 정향(Eugenia caryophyllata)의 알칼리 추출물로부터 에탄올 침전, cetavlon 처리 및 한외여과를 거쳐 분획하였다. EC-2B 획분은 APTT에서 항응고 활성을 가지는 반면, EC-2C 획분은 APTT와 TT 모두에서 항응고 활성을 가지고 있으며 EC-2B와 EC-2C에서 모두 혈소판 응집억제능을 관찰할 수 있었다. EC-2B와 EC-2C 획분의 경구투여에서 두 획분 모두 독성이 없었으며 EC-2B 획문은 1,000 mg/kg (mouse, intravenours)에서도 독성이 없었으나, EC-2C 획분은 LD50 322 mg/kg 정도의 독성을 가지고 있었다. 두 획분의 in vivo 성에서의 항응고 활성을 60% 생존율을 갖는 dose로 표시한 결과 EC-2B는 131 mg/kgdlsep 비해 EC-2C는 58 mg/kg로 활성의 차이가 in vitro에서 보다 크게 나타났다. 이 두획분을 sulfation시킨 후 활성의 변화를 ex vivo를 통해 확인한 결과 두 획분 모두 활성이 증가하였으며 특히 EC-2B 획분의 활성이 급격히 증가하였다.

• Corrosion Science and Technology
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• 제12권1호
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• pp.56-64
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• 2013

An Eectrolytic Corrosion(EC) test method was evaluated by the comparison with Copper Accelerated Acetic Salt Spray(CASS) and Neutral Salt Spray(SS) tests. Those methods were applied in order to evaluate corrosion resistance of Ni-Cr plated and Zn-plated Fe substrates. The correlations between results obtained by different test methods were investigated. Results showed that the electrochemical method such as the EC test method was superior to the conventional methods such as CASS and SS, in terms of the quantitative accuracy and the test-time span. Furthermore, the EC test method provided the useful means to estimate the initiation of corrosion of each layer by monitoring the rest potentials of the coated layers such as Ni, Cr, and Zn on Fe substrate. With regard to test time spans, the EC test provided the 78 times and 182 times faster results than the CASS test in cases of $Fe+5{\mu}m$ $Ni+0.5{\mu}m$ Cr and $Fe+20{\mu}m$ $Ni+0.5{\mu}m$ Cr respectively, while the EC test was 85 times faster results than the Salt Spray test in the case of $Fe+20g/m^2$ Zn. Therefore, the EC test can be the better method to evaluate the resistance to corrosion of coated layers than the conventional methods such as the SS test and the CASS.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2003년도 추계공동학술대회
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• pp.109-131
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• 2003

This Study intends to find the impact of industry type on the relationship between Electronic Commerce(EC) implementation and performance. For this purpose, empirical study of domestic small and medium enterprises(SMEs) is carried out to test the relationship between EC implementation and EC performance and the moderating effect of industry type on the relationship between them. Previous empirical studies on EC mostly focused on the adoption of EC by business firms, and also have been carried out with the data from big enterprises. More often than not, the results obtained from the large business firms are used to provide the guidelines for SMEs. SMEs are, however, different from large business firms in many aspects, and need to be studied on their own. Empirical test shows that there are differences between manufacturing industry and service industry in utilizing EC and in achieving EC performance. The results of data analysis indicate that the industry type of SMEs is moderating the relationship between EC implementation variables(EC type, EC strategy, EC formality and EC character) and EC performance variables(EC utilization, EC satisfaction and EC usefulness).

• The Korean Journal of Pain
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• 제35권1호
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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.

• 한국정보기술응용학회:학술대회논문집
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• 한국정보기술응용학회 2005년도 6th 2005 International Conference on Computers, Communications and System
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• pp.357-360
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• 2005

Domestic enterprises are surveyed and analyzed to find the empirical relationship between environmental characteristics and electronic commerce(EC) performance. Dynamism, hostility and heterogeneity are selected as environmental characteristics. EC performance is articulated as EC utilization, EC satisfaction and EC usefulness. Empirical test presents that dynamism has a statistically significant relationship with EC performance except EC usefulness, but hostility and heterogeneity have no statistically significant relationship with EC performance. The impact of industry type on environmental characteristics and EC performance is also tested.

• 대한환경공학회지
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• 제34권12호
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• pp.828-834
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• 2012

본 연구는 발광박테리아(Vibrio fischeri)를 생물종으로 이용하는 생태독성 검출장치의 개발을 목적으로 수행되었다. 시험용으로 제작된 생태독성 검출장치(Test jig)를 이용하여 6가 크롬, 아연, 납, 카드뮴, 구리, 수은 등 6종의 중금속류에 대한 독성 검출특성을 검토하였다. 결과적으로, 검토된 Test jig로 각 중금속류의 농도에 따라 발광박테리아의 상대적인 발광값(Relative Luminescence Unit, RLU)이 일정하게 감소하는 검출특성을 얻을 수 있었다. 타 중금속류와 달리, 납과 수은은 저농도에서 일정한 감소경향을 갖는 RLU가 얻어졌으나, 수은의 경우는 0.13 mg/L에서 0.25 mg/L로 농도를 증가시켰을 때, RLU의 감소가 급격히 진행되는 것으로 나타났다. $EC_{50}$ 산출 결과, 6가 크롬, 아연, 납, 카드뮴 등은 노출 후 시간이 경과함에 따라 $EC_{50}$이 점차적으로 감소하였다. 반면, 구리와 수은의 경우에는 $EC_{50}$이 노출 이후 시간경과에 따라 크게 변동이 없는 나타났다. 한편, Reference device와의 비교를 통해 Test jig의 독성검출 정확도를 확인한 결과, 두 장치의 $EC_{50}$값에 큰 차이가 없는 것으로 나타났으며, 또한, 기존 문헌에 제시된 $EC_{50}$값들과도 거의 유사한 수준인 것으로 확인되었다. 결과적으로, Test jig의 중금속류에 대한 생태독성 검출 장치로써의 적용가능성을 확인할 수 있었으며, 본 실험에서 얻어진 중금속류에 대한 발광박테리아의 독성 검출값들은 실시간 생태독성 모니터링 장치 개발을 위한 기초자료로 활용될 수 있을 것으로 판단된다.

• 농약과학회지
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• 제16권4호
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• pp.376-382
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• 2012

식물추출물 함유(마늘추출액, 잔톡실럼오일, 레몬그라스오일 30%) 유제의 물벼룩급성독성 결과 마늘추출액 함유 30% 유제의 $EC_{50}$은 $3.3mg\;L^{-1}$로 EPA 기준으로 보통독성정도이었고, 레몬그라스오일, 잔톡실럼(Zanthoxylum)오일 함유 30% 유제의 $EC_{50}$는 $10mg\;L^{-1}$ 이상으로 저독성이었다. 송사리급성독성 시험의 경우, 마늘추출액 함유 30% 유제의 $LC_{50}$ 값이 $3.0mg\;L^{-1}$으로 나타났으며 나머지 두 유제는 모두 $10mg\;L^{-1}$ 이상으로 확인되었다. 꿀벌급성독성시험은 접촉과 섭식 시험으로 나누어서 실시하였고, 접촉독성의 경우 모두 100 a.i ${\mu}g\;bee^{-1}$ 이상으로 확인되었다. 섭식독성의 경우 마늘추출액 함유 30% 유제의 $LD_{50}$ 값이 44.3 a.i ${\mu}g\;bee^{-1}$ 이었으며 잔톡실럼(Zanthoxylum)오일과 레몬그라스오일 함유 30% 유제의 경우 $LD_{50}$ 값이 100 a.i ${\mu}g\;bee^{-1}$ 이상으로 나타나 독성이 낮은 것으로 판단되었다. 지렁이급성독성시험의 경우, 마늘추출액, 잔톡실럼(Zanthoxylum)오일, 레몬그라스오일 함유 30% 유제의 $LC_{50}$ 값이 각각 267, 592, $430mg\;kg^{-1}$ 로 나타났는데 이는 제품살포물량을 확정한 뒤 환경추정농도를 이용한 위해성평가를 통해 안전성을 확보한다면 친환경 농자재로서 활용이 가능할 것으로 판단하였다.

• 한국공작기계학회논문집
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• 제14권3호
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• pp.116-121
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• 2005

The objective of this paper is to compare the site-to-site variability of ISO 10844 pass by the noise test sites. In order to investigate the site-to-site variance of test surfaces, European commercial tires are tested at seven different test sites. Three Korea test sites and four Europe test sites are selected. The pass by noise test is done according to a 2001/43/EC regulation. Although the ISO surface has a very specific track composition, it does not reduce the variation of pass by noise measurements over the surface of test sites. This paper shows that the test results of pass by noise level are different depending on the test sites. The correlation obtained in this work is able to predict the pass by noise level for certain test site using the data measured from another test site. The prediction value is range with an error within 1dB(A).

• KSBB Journal
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• 제15권3호
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• pp.299-306
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• 2000

발광미생물 (luminescent bacteria)인 P. phosphoreum을 이용한 수계의 환경독성물질로 지정된 ethane, benzene, phenol류에 chlorine이 치환된 l47~의 독성강도를 생체발광의 50%저하시키 는 독성농도인 ECso값을 통한 생물학적 정량을 하였을 때 phenol) benzene) ethane 의 순서로 독성깅도가 높게 산출되 어졌으며, 특히 지환된 chlo괴ne의 수가 증가할수록 독성강도가 강하다는 것을 알 수 있었다. 또한 산출된 ECso값을 이용허여 독성물질들의 물려화학적 parameter특성인 octan이(water 분할계 수 (log P), 용해도 (log S) 및 solvatochromic parameter의 떤관쟁 을 QSAR 모탤링하였으며 실힘을 통하지 않고, 독성의 독성강도 를 예측할 수 있는 회기식을 다음과 같이 산출하였다. $log EC_{50} =2.48 + 0.914 log S(n=9 R2=85.5% RE=0.378) log EC_{50}=0.35 - 4.48 Vi/100 + 2.84 \pi^* +9.46{\beta}m-4.48am (n =14 R2=98.2% RE=0.012) log EC_{50} =2.64 -1.66 log P(n=5, R2=98.8% RE=0.16) log EC_{50}=3.44 -1.09 log P(n=9 R2= 80.8% Re=0.207)$. QSAR 모델은 QSAR 검증식을 통하여 확인된 다중회기식을 이용함으로 실험하지 않은 독성물 질이 갖는 물리화학적인 특성을 대입하여 log Eeso값을 예측할 수 있으므로 경제적, 시간적으로 이익을 얻을 수 있는 모델이다.