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검색결과 : 82
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1

관광경영학회 관광경영연구 제19권 제5호 통권 67호 2015.11 pp.177-194

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The aim of this study is to analyze the effect of passengers’ perceived value on online customer satisfaction, trust and loyalty of Low-cost airlines, by conducting a survey on passengers who had experienced Low Cost Carriers in international and/or domestic flights. The result of factor analysis suggested 3 categories of perceived value-functional value, emotional value, and social value. Test of hypotheses supported the significant relationships among the variables. Findings indicated that perceived value has significant effects on the satisfaction and trust on airline, which, in turn, enhances customer loyalty. In particular, the effect of functional value was significant to both international and domestic flights, implying that providing a reasonable airfare is the most important. In addition, emotional value had a significant and direct effect on trust in international flights, indicating that emotional exchange and homey services are critical to increasing trust on the airline. Based on the study’s findings, Low-cost airlines are recommended to establish differentiated and customer-oriented marketing strategies to attract loyal customers as well as provide reasonable airfare and homey services so as to meet the expectations of customers and their perceived value for respective routes.

5,200원

2

관광경영학회 관광경영연구 제10권 제2호 통권 27호 2006.06 pp.47-71

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6,300원

3

한국호텔리조트학회 호텔리조트연구 제16권 제1호 2017.02 pp.137-150

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The objective of this study is to examine the relationship of Airline employee's supervisor trust and innovative behavior related the two type of leadership – transformational leadership and servant leadership. This study used a self-administered questionnaire to airline ground staffs from two national carriers and a total of 255 questionnaires were used for analysis. The results show that both leaderships have effect on employee's supervisor trust. However servant leadership has stronger effect toward supervisors than transformational leadership. It means the changing times are encouraging the leader to take care of their staffs sincerely rather than reign over their team. Furthermore it was found that employee's supervisor trust and innovative behavior were related positively. Therefore airline team managers or supervisors need both transformational and servant leadership in order to secure trust from their subordinate or colleague. The trust will derive employee's innovative behavior and consequently it will enhance their business performance.

4,600원

4

한국호텔리조트학회 호텔리조트연구 제15권 제3호 2016.08 pp.291-306

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The purpose of this study was to identify the effects of overseas travel experience on traveller’s pleasure and further traveller’s pleasure to post-purchase behavior, and the survey was questioned to the tourist who visited Western Europe. The survey was carried out to 220 travellers who have experienced high quality Western Europe tour, and 212 valid samples among them were used for analysis. The result of the factor analysis showed four factors regarding overseas travel experience, which were entertainment experience, esthetic experience, education experience and escape experience. And one factor for pleasure and two factors of satisfaction and loyalty for post-purchase behavior. According to hypothesis test result, the esthetic experience had the strongest influence on traveller’s pleasure. The escape and entertainment experiences were the next most influence on pleasure. But education experience did not influence on pleasure. The study showed that the pleasure of experience had positive impact on satisfaction and loyalty. In conclusion, the various experience of travel abroad increased traveller’s pleasure and proved as a factor to increase the satisfaction and loyalty.

4,900원

5

재활용폐자원 매입세액공제제도 개선방안

한국상업교육학회 상업교육연구 제30권 제3호 2016.06 pp.91-111

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부가가치세법상 매입세액공제 제도는 우리나라의 현행 부가가치세제의 근간을 이루는 중요한 요소이다. 현행 재활용폐자원 등의 매입에 관한 매입세액공제제도는 판매자가 정상적인 부가가치세를 거래징수할 수 있는 자가 아니기에 매입세액을 공제받을 여지가 없음에도 정책적 목적에 따라 조세특례제한법에 근거하여 한시적으로만 매입세액공제를 허용해주고 있는 실정이다. 이에 따라 이 제도는 예측가능성과 과세형평성 측면에서의 문제가 발생될 가능성이 있다. 본 연구의 목적은 재활용폐자원 등의 매입에 관한 현행 매입세액공제제도를 체계적으로 분석 ․ 검토하고, 개선방안을 제시하는 것이다. 연구 결과, 재활용폐자원 등에 관한 매입세액공제제도가 발전되기 위한 개선방향으로 첫째, 주된 사업여부 조건 완화를 통한 적용대상 사업자 확대, 둘째, 현재 일부 열거항목에 대해서만 적용되는 적용대상 품목의 확대, 셋째, 미등록사업자인 거래 상대방의 총공급가액 확인의무 완화, 그리고 마지막으로 재활용폐자원 매입세액공제율 환원 등이 제시되었다. 본 연구는 관련 분야의 기존 연구들과 달리 이론적 배경 및 최근의 판례를 함께 검토하여 관련 문제점 및 개선방안을 제시한 연구로써, 재활용폐자원 매입세액 공제제도의 발전 방안을 모색하기 위해 필요한 논의의 기초자료를 제공함으로써 관련 분야의 연구에 공헌할 것으로 기대된다.
The purpose of this study is to examine the Deemed Input Tax Deduction System on Recycling of Scrapped Materials, and to suggest improvements. For this purpose, we described prior literature review and we examined various researches to provide understanding of the Deemed Input Tax Deduction on Recycling of Scrapped Materials. The Deemed Input Tax Deduction on Recycling of Scrapped Materials has been continued in the uncertain legal grounds. The tax authority has temporarily allowed to the Deemed Input Tax Deduction system on Recycling of Scrapped Materials. But these allowance include the claims to the contrary with regard to the Deemed Input Tax Deductionon Recycling of Scrapped Materials. This study was an analytical review of a legal precedent about the Deemed Input Tax Deduction on Recycling of Scrapped Materials, and to suggest improvements. The basic propositions of development direction of the Deemed Input Tax Deduction system on Recycling of Scrapped Materials are as follows. First, Expansion of the Covered subjects, Second, Expansion of the Covered items, Third, (Unregistered operators counterparty’s) Mitigation of the Ensure obligation to the supply value, And finally, Restoration of the deemed Input Tax Deduction rate and so on. This study analytically assessed the controversy of the Deemed Input Tax Deduction on Recycling of Scrapped Materials. This study contributes in that it provides a basis for the discussions required in order to seek development plans related the Deemed Input Tax Deduction on Recycling of Scrapped Materials.

5,700원

6

여행사 종사원의 고객지향성 증진 방안 연구

한국호텔리조트학회 호텔리조트연구 제14권 제2호 2015.05 pp.219-233

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This study aims to suggest the improvement measures of customer orientation for travel agents’ employee through implementation of internal marketing in order to improve customer service. Through various previous studies, internal marketing is composed 4 factors – reward system, empowerment, education & training and internal communication, and customer orientation is composed 2 factors – enjoyment and needs in this study on the basis of Brown et al.'s study (2002), even though previous customer orientation researches have been studied single level factor. So this study can examine more detailed relation of effects on composed factors of customer orientation by internal marketing implementation. The result of empirical analysis on hypothesis shows that reward system and education & training made positive effect on enjoyment factor, and reward system, education & training and internal communication had positive effect on needs factor of customer orientation. Finally internal marketing implementation was found to influence differences effect on particular composed factors.

4,800원

7

관광경영학회 관광경영연구 제15권 제4호 통권 49호 2011.12 pp.287-307

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This study tried to verify the influence how the customization affect on customer loyalty and repurchase intention, these are essential factors for the customers to evaluate service in experience to the hotel industry. Also, the practical analysis has been done by customers who had ever used hotel restaurants located in Seoul to cross-check how the customer trust affect mediating effects on the relationships between customization and customer loyalty and repurchase intention. The results of the practical analysis discovered that the customization and the customer trust make influence on customer loyalty and repurchase intention. And the Customer Trust affect mediating effects on the relationships between customization and customer loyalty, repurchase intention. The ultimate results of this study brings up the new direction in ways the training of the hotel employees and customer relationship marketing in management of the hotel restaurants.

5,700원

8

관광경영학회 관광경영연구 제7권 제3호 통권 19호 2003.10 pp.167-192

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6,400원

9

광주 지역에서 aethalometer 측정 블랙 카본 입자의 질량흡수단면 평가

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.34 No.5 2018 pp.727-734

협약을 통해 무료로 제공되는 자료로, 원문이용 방식은 연계기관의 정책을 따르고 있습니다.

In this study, real-time absorption coefficients of carbonaceous species in $PM_{2.5}$ was observed using a dual-spot 7-wavelength Aethalometer between November 1, 2016 and December 31, 2017 at an urban site of Gwangju. In addition, 24-hr integrated $PM_{2.5}$ samples were simultaneously collected at the same site and analyzed for organic carbon and elemental carbon (OC and EC) using the thermal-optical transmittance protocol. A main objective of this study was to estimate mass absorption cross section (MAC) values of black carbon (BC) particles at the study site using the linear regression between aethalometer-based absorption coefficient and filter-based EC concentration. BC particles observed at 880 nm is mainly emitted from combustion of fossil fuels, and their concentration is typically reported as equivalent BC concentration (eBC). eBC concentration calculated using MAC value of $7.77m^2/g$ at wavelength of 880 nm, which was proposed by a manufacturer, ranged from 0.3 to $7.4{\mu}g/m^3$ with an average value of $1.9{\pm}1.2{\mu}g/m^3$, accounting for 7.3% (1.5~20.9%) of $PM_{2.5}$. The relationship between aerosol absorption coefficients at 880 nm and EC concentrations provided BC MAC value of $15.2m^2/g$, ranging from 11.4 to $16.2m^2/g$. The eBC concentrations calculated using the estimated MAC of $15.2m^2/g$ were significantly lower than those reported originally from aethalometer, and ranged from 0.2 to $3.8{\mu}g/m^3$, with an average of $1.0{\pm}0.6{\mu}g/m^3$, accounting for 3.7% of $PM_{2.5}$ (0.8~10.7%). Result from this study suggests that if the MAC value recommended by the manufacturer is applied to calculate the equivalent BC concentration and radiative forcing due to BC absorption, they would result in significant errors, implying investigation of an unique MAC value of BC particles at a study site.

10

대기 정체와 수용성 에어로졸 입자의 질량크기분포의 관계

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.34 No.3 2018 pp.418-429

협약을 통해 무료로 제공되는 자료로, 원문이용 방식은 연계기관의 정책을 따르고 있습니다.

Measurements of 24-hr size-segregated ambient particles were made at an urban site of Gwangju under high pressure conditions occurred in the Korean Peninsula late in March 2018. The aim of this study was to understand the effect of air stagnation on mass size distributions and formation pathways of water-soluble organic and inorganic components. During the study period, the $NO_3{^-}$, $SO_4{^{2-}}$, $NH_4{^+}$, water-soluble organic carbon (WSOC), and humic-like substances(HULIS) exhibited mostly bi-modal size distributions peaking at 1.0 and $6.2{\mu}m$, with predominant droplet modes. In particular, outstanding droplet mode size distributions were observed on March 25 when a severe haze occurred due to stable air conditions and long range transport of aerosol particles from northeastern regions of China. Air stagnation conditions and high relative humidity during the study period resulted in accumulation of primary aerosol particles from local emission sources and enhanced formation of secondary ionic and organic aerosols through aqueous-phase oxidations of $SO_2$, $NO_2$, $NH_3$, and volatile organic compounds, leading to their dominant droplet mode size distributions at particle size of $1.0{\mu}m$. From the size distribution of $K^+$ in accumulation mode, it can be inferred that in addition to the secondary organic aerosol formations, accumulation mode WSOC and HULIS could be partly attributed to biomass burning emissions.

11

대기오염집중측정소별 2013~2015년 사이의 PM2.5 화학적 특성 차이 및 유발인자 조사

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.34 No.1 2018 pp.16-37

협약을 통해 무료로 제공되는 자료로, 원문이용 방식은 연계기관의 정책을 따르고 있습니다.

In this study, difference in chemical composition of $PM_{2.5}$ observed between the year 2013 and 2015 at six air quality intensive monitoring stations (Bangryenogdo (BR), Seoul (SL), Daejeon (DJ), Gwangju (GJ), Ulsan (US), and Jeju (JJ)) was investigated and the possible factors causing their difference were also discussed. $PM_{2.5}$, organic and elemental carbon (OC and EC), and water-soluble ionic species concentrations were observed on a hourly basis in the six stations. The difference in chemical composition by regions was examined based on emissions of gaseous criteria pollutants (CO, $SO_2$, and $NO_2$), meteorological parameters (wind speed, temperature, and relative humidity), and origins and transport pathways of air masses. For the years 2013 and 2014, annual average $PM_{2.5}$ was in the order of SL ($${\sim_=}DJ$$)>GJ>BR>US>JJ, but the highest concentration in 2015 was found at DJ, following by GJ ($${\sim_=}SJ$$)>BR>US>JJ. Similar patterns were found in $SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$. Lower $PM_{2.5}$ at SL than at DJ and GJ was resulted from low concentrations of secondary ionic species. Annual average concentrations of OC and EC by regions had no big difference among the years, but their patterns were distinct from the $PM_{2.5}$, $SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$ concentrations by regions. 4-day air mass backward trajectory calculations indicated that in the event of daily average $PM_{2.5}$ exceeding the monthly average values, >70% of the air masses reaching the all stations were coming from northeastern Chinese polluted regions, indicating the long-range transportation (LTP) was an important contributor to $PM_{2.5}$ and its chemical composition at the stations. Lower concentrations of secondary ionic species and $PM_{2.5}$ at SL in 2015 than those at DJ and GJ sites were due to the decrease in impact by LTP from polluted Chinese regions, rather than the difference in local emissions of criteria gas pollutants ($SO_2$, $NO_2$, and $NH_3$) among the SL, DJ, and GJ sites. The difference in annual average $SO{_4}^{2-}$ by regions was resulted from combination of the difference in local $SO_2$ emissions and chemical conversion of $SO_2$ to $SO{_4}^{2-}$, and LTP from China. However, the $SO{_4}^{2-}$ at the sites were more influenced by LTP than the formation by chemical transformation of locally emitted $SO_2$. The $NO_3{^-}$ increase was closely associated with the increase in local emissions of nitrogen oxides at four urban sites except for the BR and JJ, as well as the LTP with a small contribution. Among the meterological parameters (wind speed, temperature, and relative humidity), the ambient temperature was most important factor to control the variation of $PM_{2.5}$ and its major chemical components concentrations. In other words, as the average temperature increases, the $PM_{2.5}$, OC, EC, and $NO_3{^-}$ concentrations showed a decreasing tendency, especially with a prominent feature in $NO_3{^-}$. Results from a case study that examined the $PM_{2.5}$ and its major chemical data observed between February 19 and March 2, 2014 at the all stations suggest that ambient $SO{_4}^{2-}$ and $NO_3{^-}$ concentrations are not necessarily proportional to the concentrations of their precursor emissions because the rates at which they form and their gas/particle partitioning may be controlled by factors (e.g., long range transportation) other than the concentration of the precursor gases.

12

겨울 및 여름철 백령도와 서울에서 측정한 PM2.5 오염 특성

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.34 No.1 2018 pp.38-55

협약을 통해 무료로 제공되는 자료로, 원문이용 방식은 연계기관의 정책을 따르고 있습니다.

Hourly measurements of $PM_{2.5}$ mass, organic and elemental carbon (OC and EC), and water-soluble ionic species were made at the air quality intensive monitoring stations in Baengryeongdo (BR) and Seoul (SL) during the winter (December 01~31, 2013) and summer (July 10~23, 2014) periods, to investigate the increase of $PM_{2.5}$ and secondary ionic species and the reasons leading to their increase during the two seasons. During winter, $PM_{2.5}$ and its major chemical species concentrations were higher at SL than at BR. Contribution of organic mass to $PM_{2.5}$ was approximately 1.7 times higher at BR than at SL, but the $NO_3{^-}$ contribution was two times higher at SL. Total concentration of secondary ionic species ($SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$) at BR and SL sites accounted for 29.1 and 40.1% of $PM_{2.5}$, respectively. However, during summer, no significant difference in chemical composition of $PM_{2.5}$ was found between the two sites with the exception of $SO{_4}^{2-}$. Total concentration of the secondary ionic species constituted on average 43.9% of $PM_{2.5}$ at BR and 53.0% at SL. A noticeable difference in chemical composition between the two sites during summer was attributed to $SO{_4}^{2-}$, with approximately twofold concentration and 10% higher contribution in SL. Low wind speed and high relative humidity were important factors in secondary formation of water-soluble ionic species during winter at SL, resulting in $PM_{2.5}$ increase. While the secondary formation during summer was attributed to strong photochemical processes in daytime and high relative humidity in nighttime hours. The increase of $PM_{2.5}$ and its secondary ionic species during the winter haze pollution period at SL was mainly caused either by long-range transport (LTP) from the eastern Chinese regions, or by local pollution. However, the increased $SO{_4}^{2-}$ and $NO_3{^-}$ during summer at SL were mainly caused by LTP, photochemical processes in daytime hours, and heterogeneous processes in nighttime hours.

13

다파장 Dual-spot Aethalometer를 이용한 갈색탄소의 광흡수계수 평가

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.34 No.2 2018 pp.207-222

협약을 통해 무료로 제공되는 자료로, 원문이용 방식은 연계기관의 정책을 따르고 있습니다.

In this study, light absorption of carbonaceous species in $PM_{2.5}$ was investigated using a dual-spot 7-wavelength Aethalometer(model AE33) with 1-min time interval between January 01 and September 30, 2017 at an urban site of Gwangju. During the study period, two Asian dust (AD) events occurred in April (AD I) and May (AD II), respectively, during which light absorption in total suspended particles was observed. Black carbon (BC) was the dominant light absorbing aerosol component at all wavelengths over the study period. Light absorption coefficients by aerosol particles were found to have 2.7~3.3 times higher at 370 nm than at 880 nm. This would be attributed to light absorbing organic aerosols, which is called brown carbon (BrC), as well as BC as absorbing agents of aerosol particles. Monthly average absorption ${{\AA}}ngstr{\ddot{o}}m$ exponent ($AAE_{370-950nm}$) calculated over wavelength range of 370~950 nm ranged from 1.10 to 1.35, which was lower than the $AAE_{370-520nm}$ values ranging from 1.19~1.68 that was enhanced due to the presence of BrC. The estimated $AAE_{370-660nm}$ of BrC ranged from 2.2 to 7.5 with an average of 4.22, which was fairly consistent to the values reported by previous studies. The BrC absorption at 370 nm contributed 10.4~28.4% to the total aerosol absorption, with higher contribution in winter and spring and lower in summer. Average $PM_{10}$ and $PM_{2.5}$ concentrations were $108{\pm}36$ and $24{\pm}14{\mu}g/m^3$ during AD I, respectively, and $164{\pm}66$ and $43{\pm}26{\mu}g/m^3$ during AD II, respectively, implying the greater contribution of local pollution and/or regional pollution to $PM_{2.5}$ during the AD II. BC concentration and aerosol light absorption at 370 nm were relatively high in AD II, compared to those in AD I. Strong spectral dependence of aerosol light absorption was clearly found during the two AD events. $AAE_{370-660nm}$ of both light absorbing organic aerosols and dust particles during the AD I and II was $4.8{\pm}0.5$ and $6.2{\pm}0.7$, respectively. Higher AAE value during the AD II could be attributed to mixed enhanced urban pollution and dust aerosols. Absorption contribution by the light absorbing organic and dust aerosols estimated at 370 nm to the total light absorption was approximately 19% before and after the AD events, but it increased to 32.9~35.0% during the AD events. In conclusion, results from this study support enhancement of the aerosol light absorption due to Asian dust particles observed at the site.

14

광주 지역에서 2015년 10월에 발생한 PM2.5 고농도 사례 특성 분석

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.34 No.4 2018 pp.567-587

협약을 통해 무료로 제공되는 자료로, 원문이용 방식은 연계기관의 정책을 따르고 있습니다.

A severe haze event occurred in October 2015 in Gwangju, Korea. In this study, the driving chemical species and the formation mechanisms of $PM_{2.5}$ pollution were investigated to better understand the haze event. Hourly concentrations of $PM_{2.5}$, organic and elemental carbon, water-soluble ions, and elemental constituents were measured at the air quality intensive monitoring station in Gwangju. The haze event occurred was attributed to a significant contribution (72.3%) of secondary inorganic species concentration to the $PM_{2.5}$, along with the contribution of organic aerosols that were strongly attributed to traffic emissions over the study site. MODIS images, weather charts, and air mass backward trajectories supported the significant impact of long-range transportation (LTP) of aerosol particles from northeastern China on haze formation over Gwangju in October 2015. The driving factor for the haze formation was stagnant atmospheric flows around the Korean peninsula, and high relative humidity (RH) promoted the haze formation at the site. Under the high RH conditions, $SO{_4}^{2-}$ and $NO_3{^-}$ were mainly produced through the heterogenous aqueous-phase reactions of $SO_2$ and $NO_2$, respectively. Moreover, hourly $O_3$ concentration during the study period was highly elevated, with hourly peaks ranging from 79 to 95ppb, suggesting that photochemical reaction was a possible formation process of secondary aerosols. Over the $PM_{2.5}$ pollution, behavior and formation of secondary ionic species varied with the difference in the impact of LTP. Prior to October 19 when the influence of LTP was low, increasing rate in $NO_3{^-}$ was greater than that in $NO_2$, but both $SO_2$ and $SO{_4}^{2-}$ had similar increasing rates. While, after October 20 when the impact of haze by LTP was significant, $SO{_4}^{2-}$ and $NO_3{^-}$ concentrations increased significantly more than their gaseous precursors, but with greater increasing rate of $NO_3{^-}$. These results suggest the enhanced secondary transformation of $SO_2$ and $NO_2$ during the haze event. Overall, the result from the study suggests that control of anthropogenic combustion sources including vehicle emissions is needed to reduce the high levels of nitrogen oxide and $NO_3{^-}$ and the high $PM_{2.5}$ pollution occurred over fall season in Gwangju.

15

Isocratic 조건하에서 HPLC를 이용한 산업시설 배출가스 중 포름 알데하이드 분석

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.34 No.4 2018 pp.616-624

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In this study, a previous DNPH (2,4-dinitrophenylhydrazine) coupled with high performance liquid chromatography (HPLC) method to measure the concentration of formaldehyde in ambient and source environments has been improved. To improve the disadvantage of the previous HPLC method, an appropriate composition ratio of mobile phase (water: acetonitrile (ACN)) was determined and an isocratic analysis was conducted. Furthermore, limit of detection (LOD), limit of quantitation(LOQ), accuracy, and precision were investigated to verify the reliability of the analytical conditions determined. Finally, samples of exhaust gases from five different industrial facilities were applied to HPLC analytial method proposed to determine their formaldehyde concentrations. The appropriate composition ratio of the mobile phase under the isocratic condition was a mixture of water(40%) and ACN(60%). As the volume fraction of the organic solvent ACN increases, retention time of the formaldehyde peak was reduced. Detection time of formaldehyde peak determined using the proposed isocratic method was reduced from 7 minutes(previous HPLC method) to approximately 3 minutes. LOD, LOQ, accuracy, and precision of the formaldehyde determined using standard solutions were 0.787 ppm, 2.507 ppm, 93.1%, and 0.33%, respectively, all of which are within their recommended ranges. Average concentrations of the formaldehyde in five exhaust gases ranged from 0.054 ppm to 1.159 ppm. The lowest concentration (0.054 ppm) was found at samples from waste gas incinerator in a bisphenol-A manufacturing plant. The highest was observed at samples from the absorption process in manufacturing facilities of chemicals including formaldehyde and hexamine. The analytical time of the formaldehyde in ambient air can be shortened by using the isocratic analytical method under appropriate mobile phase conditions.

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도시지역 PM2.5의 HULIS 화학 특성 및 발생 과정 조사

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.31 No.3 2015 pp.239-254

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Little information on HUmic-Like Substances (HULIS) in ambient particulate matter has been reported yet in Korea. HULIS makes up a significant fraction of the water-soluble organic mass in the atmospheric aerosols and influence their water uptake properties. In this study 24-hr $PM_{2.5}$ samples were collected between December 2013 and October 2014 at an urban site in Gwangju and analyzed for organic carbon (OC), elemental carbon (EC), water-soluble OC (WSOC), HULIS, and ionic species, to investigate possible sources and formation processes of HULIS. HULIS was separated using solid phase extraction method and quantified by total organic carbon analyzer. During the study period, HULIS concentration ranged from 0.19 to $5.65{\mu}gC/m^3$ with an average of $1.83{\pm}1.22{\mu}gC/m^3$, accounting for on average 45% of the WSOC (12~ 73%), with higher in cold season than in warm season. Strong correlation of WSOC with HULIS ($R^2=0.91$) indicates their similar chemical characteristics. On the basis of the relationships between HULIS and a variety of chemical species (EC, $K^+$, $NO_3{^-}$, $SO_4{^{2-}}$, and oxalate), it was postulated that HULIS observed during summer and winter were likely attributed to secondary formation and primary emissions from biomass burning (BB) and traffics. Stronger correlation of HULIS with $K^+$, which is a BB tracer, in winter ($R^2=0.81$) than in summer ($R^2=0.66$), suggests more significant contribution of BB emissions in winter to the observed HULIS. It is interesting to note that BB emissions may also have an influence on the HULIS in summer, but further study using levoglucosan that is a unique organic marker of BB emissions is required during summer. Higher correlation between HULIS and oxalate, which is mainly formed through cloud processing and/or photochemical oxidation processes, was found in the summer ($R^2=0.76$) than in the winter ($R^2=0.63$), reflecting a high fraction of secondary organic aerosol in the summer.

17

광주지역 PM2.5의 고농도 오염현상 조사

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.31 No.3 2015 pp.269-286

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24-hr integrated $PM_{2.5}$ measurements were performed between December 2013 and October 2014 at an urban site in Gwangju and the collected samples were analyzed for organic carbon (OC), elemental carbon (EC), ionic species, and elemental species. Objectives of this study were to identify $PM_{2.5}$ pollution episodes, to characterize their chemical components, and to examine their probable origins. Over the course of the study period, average $PM_{2.5}$ concentration was $37.7{\pm}23.6$ $(6.0{\sim}121.5){\mu}g/m^3$. Concentrations of secondary ionic species; $NH_4{^+}$, $NO_3{^-}$, and $SO_4{^{2-}}$ was on average $5.54{\mu}g/m^3$ (0.28~ 20.86), $7.60{\mu}g/m^3$ (0.45~ 33.53), and $9.05{\mu}g/m^3$ (0.50~ 34.98), accounting for 13.7% (4.6~ 22.7), 18.6% (2.9~ 44.8), and 22.9% (4.9~ 55.1) of the $PM_{2.5}$ concentration, respectively. Average OC and EC concentrations were $5.22{\mu}g/m^3$ and $1.54{\mu}g/m^3$, taking possession of 4.6 and 22.2% (as organic mass) of the $PM_{2.5}$, respectively. Frequencies at which 24-hr averaged $PM_{2.5}$ exceeded a 24-hr averaged Korean $PM_{2.5}$ standard of $50{\mu}g/m^3$ (termed as an "episode" in this study) were 30, accounting for 21.3% of total 141 measurements. These pollution episodes were mostly associated with haze phenomenon and weak surface wind speed. It is suggested that secondary formation of aerosol was one important formation mechanism of the episodes. The episodes were associated with enhancements of organic mass, $NO_3{^-}$ and $SO_4{^{2-}}$ in winter, of $NO_3{^-}$ and $SO_4{^{2-}}$ in spring, and of $SO_4{^{2-}}$ in summer. Potential source contribution function results indicate also that $PM_{2.5}$ episodes were likely attributed to local and regional haze pollution transported from northeastern China in winter, to atmospheric processing of local emissions rather than long-range transport of air pollutants in spring, and to the $SO_4{^{2-}}$ driven by photochemistry of $SO_2$ in summer.

18

챔버 내 발생 입자를 이용한 CPC 수농도 비교 평가

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.30 No.6 2014 pp.619-630

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Two butanol-based Condensation Particle Counters (CPC 3022, CPC 3025), three water-based CPCs (CPC3781, CPC3785${\times}$2), a Gardner Counter, a Fast Mobility Particle Sizer (FMPS), and an Aerosol Electrometer (AE) were deployed to measure the number concentrations from atomized aerosol under six different conditions. Comparisons of particle number concentrations measured by the CPCs, FMPS, and AE were conducted to evaluate the performance of the each CPCs using laboratory generated artificial particles such as NaCl, succinic acid ($C_4H_6O_4$), and particles generated by propane torch & heat gun in the chamber. Good correlation between the CPC3025 and FMPS was observed for the total particle number concentrations in the size range 15 nm to 90 nm. In addition, this paper suggests that photometric mode in water-based CPC3785 could not be used as quantitative of number concentrations for CPC3785.

19

제주도 고산지역 탄소 성분의 특성 분석 - 유기탄소의 열광학적 특성 및 유기성분 중심으로

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.29 No.6 2013 pp.722-733

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Ground-based measurements were conducted from August 25 to September 8 of 2011 for understanding characteristics of carbonaceous aerosols measured at Gosan. Chemical components and their sources were discussed by analysis of organic compounds with identification of primary and secondary products in particulate matter. Thus, organic carbon (OC) and elemental carbon (EC) based on the carbonaceous thermal distribution (CTD), which provides detailed carbon signature characteristics relative to analytical temperature, was used to improve the carbon fractionation of the analytical method. In addition, organic compounds by gas chromatography technique with the backward trajectories were discussed for characteristics of carbonaceous aerosols. Different air-masses were classified related to the OC thermal signatures and the organic molecular markers such as aromatic acids and PAHs. We concluded that the aging process was influenced by the long-range transport from East Sea area.

20

산성화 과정이 황사입자 내 금속성분의 용해도에 미치는 영향: 실험실 연구결과

[Kisti 연계] 한국대기환경학회 한국대기환경학회지 Vol.29 No.1 2013 pp.64-73

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Because some particulate matter emission sources may inherently produce soluble species, or some soluble species may be produced during atmospheric transport, it is important to understand the origin of a particles's solubility when water-soluble tracers are used in source apportionment studies. Laboratory experiments were performed on three types of soils (Mongolia grassland, Mongolia desert, and Korean rural soils), to study the impact of acidification by nitric acid vapor on the solubility of metals in the soils. To achieve this goal, concentrations of water-soluble metals (Na, Mg, Al, K, Ca, Mn, and Fe) in the soils measured before and after acidification. Contributions of concentrations of water-soluble metal species before and after acidification attack to their total concentrations varied little with soil type. Concentrations of water-soluble Mg, Al, K, Ca, Mn, and Fe from the soils after interaction with nitric acid vapor increased, with significant increases in soluble Ca and Mn for all soil types suggesting soil acidification enhances the amount of leachable metal species in soil dust. There was little increase in water-soluble Na and K after acidification for each soil type. This experiment demonstrates that quantities of water-soluble metal species in particulate matter are produced under high gaseous nitric acid conditions.

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