• Title/Summary/Keyword: atmosphere model

Search Result 1,187, Processing Time 0.025 seconds

A Study on Catalytic Pyrolysis of Polypropylene with Ni/sand (Ni/sand를 이용한 폴리프로필렌 촉매 열분해 연구)

  • Kim, Soo Hyun;Lee, Roosse;Sohn, Jung Min
    • Clean Technology
    • /
    • v.27 no.3
    • /
    • pp.232-239
    • /
    • 2021
  • In order to develop a novel system named "thermal medium and gas circulation type pyrolysis system," this study was conducted to obtain basic data for process simulation before performing the pyrolysis experiment. Polypropylene (PP) was chosen as model material in the basic pyrolysis experiment instead of waste plastic and fluidized sand (hereinafter referred to as "sand"), and it was used as a heat transfer material in the "thermal medium and gas circulation type pyrolysis system." Ni was impregnated as an active catalyst on the sand to promote catalytic pyrolysis. The basic physical properties of PP were analyzed using a thermogravimetric analyzer, and pyrolysis was performed at 600 ℃ in an N2 atmosphere to produce liquid oil. The distribution of the carbon number of the liquid oil generated through the catalytic pyrolysis reaction was analyzed using GC/MS. We investigated the effects of varying the pyrolysis space velocity and catalyst amount on the yield of liquid oil and the carbon number distribution of the liquid oil. Using Ni/sand, the yield of liquid oil was increased except with the pyrolysis condition of 10 wt% Ni/sand at a space velocity of 30,000 h-1, and the composition of C6 ~ C12 hydrocarbons increased. With increases in the space velocity, higher yields of liquid oil were obtained, but the composition of C6 ~ C12 hydrocarbons was reduced. With 1 wt% Ni/sand, the oil yield obtained was greater than that obtained with 10 wt% Ni/sand. In summary, when 1 wt% Ni/sand was used at a space velocity of 10,000 h-1, the oil yield was 60.99 wt% and the composition of C6 ~ C12 hydrocarbons was highest at 42.06 area%.

Evaluation of Sensitivity and Retrieval Possibility of Land Surface Temperature in the Mid-infrared Wavelength through Radiative Transfer Simulation (복사전달모의를 통한 중적외 파장역의 민감도 분석 및 지표면온도 산출 가능성 평가)

  • Choi, Youn-Young;Suh, Myoung-Seok;Cha, DongHwan;Seo, DooChun
    • Korean Journal of Remote Sensing
    • /
    • v.38 no.6_1
    • /
    • pp.1423-1444
    • /
    • 2022
  • In this study, the sensitivity of the mid-infrared radiance to atmospheric and surface factors was analyzed using the radiative transfer model, MODerate resolution atmospheric TRANsmission (MODTRAN6)'s simulation data. The possibility of retrieving the land surface temperature (LST) using only the mid-infrared bands at night was evaluated. Based on the sensitivity results, the LST retrieval algorithm that reflects various factors for night was developed, and the level of the LST retrieval algorithm was evaluated using reference LST and observed LST. Sensitivity experiments were conducted on the atmospheric profiles, carbon dioxide, ozone, diurnal variation of LST, land surface emissivity (LSE), and satellite viewing zenith angle (VZA), which mainly affect satellite remote sensing. To evaluate the possibility of using split-window method, the mid-infrared wavelength was divided into two bands based on the transmissivity. Regardless of the band, the top of atmosphere (TOA) temperature is most affected by atmospheric profile, and is affected in order of LSE, diurnal variation of LST, and satellite VZA. In all experiments, band 1, which corresponds to the atmospheric window, has lower sensitivity, whereas band 2, which includes ozone and water vapor absorption, has higher sensitivity. The evaluation results for the LST retrieval algorithm using prescribed LST showed that the correlation coefficient (CC), the bias and the root mean squared error (RMSE) is 0.999, 0.023K and 0.437K, respectively. Also, the validation with 26 in-situ observation data in 2021 showed that the CC, bias and RMSE is 0.993, 1.875K and 2.079K, respectively. The results of this study suggest that the LST can be retrieved using different characteristics of the two bands of mid-infrared to the atmospheric and surface conditions at night. Therefore, it is necessary to retrieve the LST using satellite data equipped with sensors in the mid-infrared bands.

Analysis of Changes in Tree Height-Diameter Allometry for Major Tree Species in South Korea (우리나라 주요 수종의 수고-직경 상대생장 변화 분석)

  • Moonil Kim;Taejin Park;Youngjin Ko;Go-Mi Choi;Soonchul Son;Yejun Kang;Jaehee Yoo;Minkyeong Kim;Hyeonji Park;Woo-Kyun Lee
    • Journal of Korean Society of Forest Science
    • /
    • v.112 no.1
    • /
    • pp.71-82
    • /
    • 2023
  • Forest biomass is used as a representative indicator of forest size, maturity, and productivity. Therefore, quantitative evaluation is important for management and harvest as well as the evaluation of ecosystem functions and services including CO2 absorption. The allometric equation is a widely used method for estimating the value of each component through the relative growth rate of plants. Recently, studies indicated that the relative growth of trees is changing because of the increased CO2 concentration in the atmosphere and the resulting climate change, raising the need to review the previously developed relative growth models and coefficients. In this study, the height-diameter at breast height (DBH) relationships of four major tree species in Korea [(Pinus densiflora (PD), Larix kaempferi (LK), Quercus variabilis (QV), and Quercus mongolica (QM)] were analyzed using the 5th-7th National Forest Inventory (NFI) data. Furthermore, these results were compared with the present yield table from the National Institute for Forest Science. This analysis revealed that the expected height for the same DBH increased as the NFI progressed. For example, in model analysis, the expected heights for PD, LK, QV, and QM for DBH of 25 cm were 12.48, 19.17, 14.47, and 13.19 m, respectively, in the 5th NFI data. In the 7th NFI data, these values were estimated as 13.61 (+9.1%), 21.58 (+12.7%), 15.76 (+8.9%), and 13.93 m (+5.6%), respectively. These results indicate that the major tree species in South Korean forests currently are more vigorous in height growth than in diameter growth when compared to the height-DBH development trends by tree species identified through past survey data.

A qualitative study on the process of maintaining the 'eating alone'(honbob) lifestyle (직장인의 '혼밥' 유지 과정에 대한 질적 연구)

  • Hye Jin Kwon;Younga Ju
    • Korean Journal of Culture and Social Issue
    • /
    • v.24 no.4
    • /
    • pp.657-689
    • /
    • 2018
  • The purpose of this study is to develop a substantive theory on 'eating alone'(honbob)and the process of maintaining the lifestyle of eating alone for the need of a non-judgmental understanding on the new 'honbob' lifestyle. Data were collected through in-depth interviews with 10 male and female workers in Seoul and Gyeonggi-do, who voluntarily eat alone over 70% of their meals per week with the minimum duration of 5 years. Data analysis was performed using grounded theory proposed by Strauss & Corbin (1998) in the qualitative research method. As a result, a paradigm model on the process of maintaining 'honbob' was derived. Based on categorical analysis, the causal condition was 'not trying to tune' and the central phenomenon was 'following the desire to set efficiency as the top priority. Contextual conditions were 'the atmosphere of fierce competition', 'weakening of organizational culture', 'diffusion of individualistic culture'. The intervening conditions were 'personal trait and emotional experience', 'job characteristics of less organization culture'. The action/interaction strategies were 'accepting internal conflicts', 'acting in autonomy', 'finding relationship through media', and 'distancing from superficial relationship'. The consequences were 'enjoying time for self-exploration', 'valuing self-care', 'becoming a epicurean conventionalist', and 'becoming aware of the need for balance'. The core category has been shown as 'self-oriented in accordance to priority of efficiency and being able to appreciate the importance of social group'. The Such phenomenon passes through four different stages - first, the stage of weighing time efficiency while beginning hon-bob; second, the stage of conflict when one feels nervous and not free from others' view; third, the stage of adjustment to justify his/her 'hon-bob'; and the final stage of balance to perceive the importance of social group while going on 'honbob'. The study had the aim of increasing the understanding and acceptance of the new 'honbob' lifestyle through an in-depth exploration of office worker's 'honbob' experience and the process of maintaining 'honbob' so the society can better accept it and, further, to embrace co-existence of various cultures.

A Study on the Effects of Lifestyle and Self-Expression Desire on Vegan Cosmetics Purchase Intention: Focusing on the Mediating Effect of Social Value (라이프스타일 유형과 자기표현욕구가 비건화장품 구매의도에미치는 영향에 관한 연구: 사회적가치의 매개효과 중심으로)

  • Kim, Jung-In;Chul-Moo Heo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.18 no.5
    • /
    • pp.217-240
    • /
    • 2023
  • For a while, Functional cosmetics, Cosmeceutical cosmetics, and Derma cosmetics have gained trust and become popular due to the consumers' strong interest in ingredients & efficacy. It's remarkable that Clean or Vegan brands are growing fast because they are emphasizing on different values from the other cosmetic brands. It's needed to attempt to analyze the influence relationship between consumer lifestyle and social value in these changes, and to find out whether the consumption of vegan cosmetics is related to satisfying the need for self-expression in a social atmosphere where ESG is emphasized on. This study analyzed the effect of lifestyle types and self-expression needs on the purchase intention of vegan cosmetics by mediating social values for cosmetics consumers. Lifestyle types were classified into appearance-oriented, health-oriented, and fashion-oriented. For empirical analysis, 321 questionnaires collected from cosmetics consumers living across the country were used. SPSS v26.0 and PROCESS macro v4.2 were used to analyze based on a single mediating model as a single mediator. As a result of the analysis, first, lifestyle types and self-expression needs, excluding appearance-oriented types, were found to have a positive (+) effect on social values. Second, it was found that social value had a positive (+) significant effect on the purchase intention of vegan cosmetics. Third, appearance-oriented, health-oriented, trend-seeking lifestyle types and self-expression needs were all found to have a positive (+) effect on the purchase intention of vegan cosmetics. Fourth, social values were found to mediate lifestyle types, self-expression needs, and purchase intentions, except for appearance-oriented types. Appearance-oriented consumers do not directly affect social values but affect purchase intentions, suggesting that appearance-oriented consumers may not be significantly affected by product-related social values. In a comparison of the relative influence size using standardization coefficients, self-expression needs had the greatest impact on the purchase intention of vegan cosmetics when mediating social values, and health-oriented ones had the least impact. The academic implications of this study include contributing to consumer behavior research by providing insights, mediation mechanisms, and consideration of the niche consumer sector, and directing further research into the cosmetics industry beyond forming marketing strategies and sustainable business practices.

  • PDF

Application and Analysis of Ocean Remote-Sensing Reflectance Quality Assurance Algorithm for GOCI-II (천리안해양위성 2호(GOCI-II) 원격반사도 품질 검증 시스템 적용 및 결과)

  • Sujung Bae;Eunkyung Lee;Jianwei Wei;Kyeong-sang Lee;Minsang Kim;Jong-kuk Choi;Jae Hyun Ahn
    • Korean Journal of Remote Sensing
    • /
    • v.39 no.6_2
    • /
    • pp.1565-1576
    • /
    • 2023
  • An atmospheric correction algorithm based on the radiative transfer model is required to obtain remote-sensing reflectance (Rrs) from the Geostationary Ocean Color Imager-II (GOCI-II) observed at the top-of-atmosphere. This Rrs derived from the atmospheric correction is utilized to estimate various marine environmental parameters such as chlorophyll-a concentration, total suspended materials concentration, and absorption of dissolved organic matter. Therefore, an atmospheric correction is a fundamental algorithm as it significantly impacts the reliability of all other color products. However, in clear waters, for example, atmospheric path radiance exceeds more than ten times higher than the water-leaving radiance in the blue wavelengths. This implies atmospheric correction is a highly error-sensitive process with a 1% error in estimating atmospheric radiance in the atmospheric correction process can cause more than 10% errors. Therefore, the quality assessment of Rrs after the atmospheric correction is essential for ensuring reliable ocean environment analysis using ocean color satellite data. In this study, a Quality Assurance (QA) algorithm based on in-situ Rrs data, which has been archived into a database using Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Bio-optical Archive and Storage System (SeaBASS), was applied and modified to consider the different spectral characteristics of GOCI-II. This method is officially employed in the National Oceanic and Atmospheric Administration (NOAA)'s ocean color satellite data processing system. It provides quality analysis scores for Rrs ranging from 0 to 1 and classifies the water types into 23 categories. When the QA algorithm is applied to the initial phase of GOCI-II data with less calibration, it shows the highest frequency at a relatively low score of 0.625. However, when the algorithm is applied to the improved GOCI-II atmospheric correction results with updated calibrations, it shows the highest frequency at a higher score of 0.875 compared to the previous results. The water types analysis using the QA algorithm indicated that parts of the East Sea, South Sea, and the Northwest Pacific Ocean are primarily characterized as relatively clear case-I waters, while the coastal areas of the Yellow Sea and the East China Sea are mainly classified as highly turbid case-II waters. We expect that the QA algorithm will support GOCI-II users in terms of not only statistically identifying Rrs resulted with significant errors but also more reliable calibration with quality assured data. The algorithm will be included in the level-2 flag data provided with GOCI-II atmospheric correction.

Study on the Relationships Among Perceived Shopping Values, Brand Equity, and Store Loyalty of Korean and Chinese Consumers: A Case of Large Discount Store (한국과 중국 소비자의 쇼핑 경험가치 지각과 브랜드자산 및 점포충성도의 관계에 관한 비교 연구: 대형 할인점을 중심으로)

  • Hwang, Soonho;Oh, Jongchul;Yoon, Sungjoon
    • Asia Marketing Journal
    • /
    • v.14 no.2
    • /
    • pp.209-237
    • /
    • 2012
  • 1. Research Purpose Consumers rely on various clues to evaluate their decision to patronize a retail store, and store brand is one of them (Dodds 1991; Grewal et al. 1998). As consumers find ever increasing variety of contact points connecting them to specific store, the value of experiential shopping as a means of increasing store's brand equity warrants greater attention from scholars of retail management. Retail shopping values are credited for creating not only cognitive experiences like brand knowledge but also emotional experiences such as shopping pleasure and pride (Schmitt 1999). This may be because today's consumers place emphasis on emotional values associated with shopping pleasure, lifestyle brought to life, brand relationship, and store atmosphere more than utilitarian values such as product quality and price. Many previous literature found this to be true (Ahn and Lee 2011; Mathwick et al. 2001). This brings forth important research issues and questions regarding the roles of shopping experiential values and brand equity with regard to consumer's retail patronage choice. However, despite this importance, research on this area remains quite inadequate (Hwang 2010). For this reason, this study aims to verify the relationships among experiential shopping values, retail store brand equity and tries to link that with customer loyalty by surveying large-scale discount store shoppers in Korea and China. 2. Research Contents In order to carry out the research objective, this study conducted comprehensive literature survey on previous literature by discussing major findings and implications with regard to shopping values and retail brand equity and store loyalty. For data collection, researcher employed survey-based research method where data were collected in two major cities of Korea (Seoul) and China (Bejing) and sampling frame was based on patrons of large discount stores in both countries. Specific research questions raised in this study are as follows; RQ1: How do Korean and Chinese consumers differently perceive of shopping values regarding shopping at large-sclae discount stores? RQ2: Are there differences in consumers' emotional consumption propensities? RQ3: Do Korean and Chinese consumers display different perceptions of brand equity towards large-scale discount stores? RQ4: Are there differences in relationships between shopping values and brand equity for Korean and Chinese consumers? For statistical analysis, SPSS17.0, AMOS17.0 and SmartPLS were employed. 3. Research Results The data collected through face-to-face survey conducted in Seoul and Bejing revealed appropriate data validity and reliability as a result of exploratory/confirmatory factor analysis and reliability tests, andh SEM model yielding satisfactory model fitness. The result of the study may be summarized by three main points. First, as a result of testing differences in consumption dispositions, Chinese consumers showed higher scores in aesthetic and symbolic dispositions, whereas Korean consumers scored higher in hedonic disposition. Second, testing on perceptions toward brand equity of large discount stores showed that Korean consumers exhibited more positive perceptions of brand awareness and brand image than Chinese counterparts. Third, the result of exploratory factor analysis on the experiential shopping values revealed different factors for each country. On Korean side, consumer interest value, aesthetic value, and hedonic value were prominent, whereas on Chinese side, hedonic value, aesthetic value, consumer interest value, and service excellence value were found salient. 4. Research Implications While many previous studies on inter-country differences in retailing area mainly focused on cultural dispositions or orientations to explain the differences, this study sets itself apart by specifically targeting individual consumer's shopping values from an experiential viewpoint. The study result provides important theoretical as well as practical implications for large-scale discount store, especially the impotance of fully exploring the linkage between shopping values and brand equity, which has significant influence on loyalty. Therefore, the specific implications deriving from the result shed some important insights upon the consumption values based on shopping experiences and brand equity. The differences found in store shoppers between the two countries may also provide useful insights for Korean and Chinese retailers who plan to expand their operations globally. Related strategic implications derived from this study is the importance of localizing retail strategy which is based on the differences found in experiential shopping values between the two country groups. Especially the finding that Chinese consumers value consumer interest and service excellence, whereas Koreans place importance on hedonic or aesthetic values indicates the need to differentiate the consumer's psychographical profiles when it comes to expanding retail operations globally. Particularly important will be to pursue price-orienated strategy in China in consideration of the high emphasis on consumer interests and service excellence, but to emphasize the symbolic aspects of brand equity in Korea by maximizing the brand equity associated with aesthetic values and hedonic orientations. 5. Recommendations This study focused on generic retail branded discount stores in both countries, thus making it difficult to tease out store-specific strategies based on specific retail brands. Future studies may benefit fro employing actual brand names in survey questionnaire to verify relationship between shopping values and brand-based store strategy. As with other studies of this nature, this study needs to strengthen the result's generalizability by selecting respondents from a wider spectrum of respondents.

  • PDF