• Title/Summary/Keyword: green development

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Semi-analytical Numerical Analysis of the Core-size and Electric-field Intensity Dependency of the Light Emission Wavelength of CdSe/ZnS Quantum Dots

  • Lee, Honyeon
    • Journal of the Semiconductor & Display Technology
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    • v.20 no.3
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    • pp.11-17
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    • 2021
  • I performed a semi-analytical numerical analysis of the effects of core size and electric field intensity on the light emission wavelength of CdSe/ZnS quantum dots (QDs). The analysis used a quantum mechanical approach; I solved the Schrödinger equation describing the electron-hole pairs of QDs. The numerical solutions are described using a basis set composed of the eigenstates of the Schrödinger equation; they are thus equivalent to analytical solutions. This semi-analytical numerical method made it simple and reliable to evaluate the dependency of QD characteristics on the QD core size and electric field intensity. As the QD core diameter changed from 9.9 to 2.5 nm, the light emission wavelength of CdSe core-only QDs varied from 262.9 to 643.8 nm, and that of CdSe/ZnS core/shell QDs from 279.9 to 697.2 nm. On application of an electric field of 8 × 105 V/cm, the emission wavelengths of green-emitting CdSe and CdSe/ZnS QDs increased by 7.7 and 3.8 nm, respectively. This semi-analytical numerical analysis will aid the choice of QD size and material, and promote the development of improved QD light-emitting devices.

Gender Differences in Influence of Socio-demographic Characteristics on Mode Choice in India

  • SAIGAL, Taru;VAISH, Arun Kr.;RAO, N.V.M.
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.1
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    • pp.531-542
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    • 2021
  • The study aims to investigate differences between men and women in influence of various socio-demographic factors on choice of mode of transport. For this purpose, a binary logit model of choice probabilities is implemented on survey data of a developing country city. Results indicate women's choice of travel mode to be more environment-friendly than that of men. Well-educated, working and middle-aged individuals appear to be the most likely to choosing more-polluting modes of transport for frequent travelling purposes. Individuals in the sample who are the least socioeconomically well off are found the most likely to be promising for the environment. The findings of this study suggest the future transportation policies toward development of existing infrastructure of greener modes of transportation in the city such as, public transportation services and pedestrian lanes, so as to manage the rising issues of degrading environmental quality. The study highlights how the consideration and inclusion of socio-demographic factors is crucial for policy recommendation regarding curtailing the environmental damages contributed by transportation sector. Because mobility crucially affects all other indicators of empowerment, and women are the ones using green modes extensively, the city's transportation system should be so developed which gives their safety and security due importance.

Analysis of the Types of External Wall and Roof Structure Layer Composition of CLT Building (CLT 건축물의 외벽 및 지붕 구조체 레이어 구성 유형 분석)

  • Yoo, Dong-Wan;Lee, Tae-Goo
    • Journal of the Korean Institute of Rural Architecture
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    • v.22 no.4
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    • pp.71-78
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    • 2020
  • Today, the whole world is going through a big chaos due to the COVID-19, but paradoxically, the emergence of COVID-19 has been leading to the need for sustainable development, such as Green New Deal that can improve global warming and carbon emissions, and the need for sustainable architecture is growing bigger and bigger in the architectural field as well. The level of CLT buildings in Korea is at a very rudimentary stage, while CLT buildings remedying existing wooden buildings are getting the spotlight among European countries for sustainable architecture. This study was conducted to categorize structure layer compositions of overseas CLT buildings and analyze architectural techniques and materials applied by collecting and analyzing information about CLT structure layer compositions of overseas CLT building-related institutions, companies and cases. When classifying structure layer compositions of foreign CLT buildings depending on the roles of layers. it was revealed that exterior wall structure layers were combined and organized within a sequence of external finishing, ventilation, waterproof, board, external insulation, airtightness, structure, airtightness, interior insulation, interior finishing, sloped roof structure layers were external finishing, ventilation, waterproof, board, external insulation, airtightness, structure, airtightness, interior insulation, interior finishing, flat roof structure layers were external finishing, ventilation, waterproof, planking wood, external insulation, waterproof, external insulation, airtightness, structure, airtightness, interior insulation, interior finishing.

Tristram Shandy: A Sentimental Journey Riding a Hobbyhorse

  • Lee, Hye-Soo
    • English & American cultural studies
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    • v.10 no.2
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    • pp.209-230
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    • 2010
  • This paper reads Tristram Shandy around the issue of hobbyhorse, Sterne's main contribution to novelistic techniques as well as his insightful understanding of the modern condition. First, Sterne represents his characters according to the principle of hobbyhorse, declaring "I will draw my uncle Toby's character from his HOBBY-HORSE." Gradually distancing himself from the Juvenalian satiric mode as well as Henry Fielding's grand narrative and Samuel Richardson's psychological realism, as is seen in the early episode of Yorick's death, Sterne suggests that the best way to represent his characters lies in describing their hobbyhorses. Sterne's foregrounding of hobbyhorse is linked with his embrace of madness as part of the modern identity. He accepts that hobbyhorse-riding, a quirky and mad habit of mind or behavior, is indispensable for some people, like Uncle Toby, to survive and get along with their otherwise unbearable lives. Uncle Toby's hobbyhorse of waging mock battles in the bowling green saves him from the perplexing real world of language and sexuality, while the fictionality of his hobbyhorsical world is exposed by Widow Wadman. Since a hobbyhorse is by definition a world of private pleasure and eccentricity, sentimentalism comes along to bridge the two virtually incommensurable hobbyhorsical world in place of linguistic communication. Yet if Tristram Shandy fully stages sentimentalism, a cardinal part of hobbyhorse riding, it also offers an awareness of it, which is a significant development in the cult of sentimentalism in the eighteenth century. Tristram Shandy performs a version of sentimental journey where each character rides his hobbyhorse and the reader is invited to ride his/her own hobbyhorse.

A Study on the Effect of Satisfaction with R&D Projects on R&D Performance Satisfaction -For SMEs in Jeollanamdo-

  • Choi, Hong Wan;Kang, Min Jung
    • International Journal of Internet, Broadcasting and Communication
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    • v.13 no.1
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    • pp.11-19
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    • 2021
  • The purpose of this study is to check whether the satisfaction of the R&D (Research & Development) project directly affects the R&D performance, and to find out whether the satisfaction with regional connectivity and the satisfaction with the R&D operation management significantly mediate the relationship that the satisfaction with the R&D project has on the R&D performance. In order to verify the research hypothesis on this, a total of 51 companies located in Jeollanam-do that actually conducted R&D research projects were surveyed and analyzed. In order to conduct an empirical study based on the collected questionnaire, a survey questionnaire related to the variables of the study model was composed based on a sample of 51 questionnaires. We used the SPSS program to verify the hypotheses in this study, and the hypotheses were verified by analyzing the validity, reliability, correlation, and deflection. As a result, there was a positive (+) significant relationship between R&D project satisfaction and R&D performance. In addition, it was found that the relationship between R&D project satisfaction and R&D performance was significantly mediated by the satisfaction with R&D regional connectivity and satisfaction with R&D project operation management.

Effect of Oxidation Behavior of (Nd,Dy)-Fe-B Magnet on Heavy Rare Earth Extraction Process

  • Park, Sangmin;Nam, Sun-Woo;Lee, Sang-Hoon;Song, Myung-Suk;Kim, Taek-Soo
    • Journal of Powder Materials
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    • v.28 no.2
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    • pp.91-96
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    • 2021
  • Rare earth magnets with excellent magnetic properties are indispensable in the electric device, wind turbine, and e-mobility industries. The demand for the development of eco-friendly recycling techniques has increased to realize sustainable green technology, and the supply of rare earth resources, which are critical for the production of permanent magnets, are limited. Liquid metal extraction (LME), which is a type of pyrometallurgical recycling, is known to selectively extract the metal forms of rare earth elements. Although several studies have been carried out on the formation of intermetallic compounds and oxides, the effect of oxide formation on the extraction efficiency in the LME process remains unknown. In this study, microstructural and phase analyses are conducted to confirm the oxidation behavior of magnets pulverized by a jaw crusher. The LME process is performed with pulverized scrap, and extraction percentages are calculated to confirm the effect of the oxide phases on the extraction of Dy during the reaction. During the L ME process, Nd is completely extracted after 6 h, while Dy remains as Dy2Fe17 and Dy-oxide. Because the decomposition rate of Dy2Fe17 is faster than the reduction rate of Dy-oxide, the importance of controlling Dy-oxide on Dy extraction is confirmed.

Challenges to the Export-Led Growth Strategy in the Digital and Global Era: An Empirical Investigation of South Korea's Experience

  • LEE, Jung Wan
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.6
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    • pp.253-265
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    • 2022
  • This paper examines South Korea's past developmental experience and its current strategy and policy initiatives to overcome global and domestic challenges and sustain economic growth in the twenty-first century, the digital and global era, to explain how the country became a high-income economy. The findings of this research highlight the following three factors: First, the most significant factor in rapid industrialization was the adoption of an outward-looking strategy, with the help of a highly skilled workforce and the development of high-tech manufacturing and services sectors, which was supported by the government plans. Second, the high R&D intensity helped South Korea become a global leader in information and communication technologies, which has emerged from a top-down innovation system that promotes close collaboration between government, industry, and the academic community. Third, according to the recently released Global Entrepreneurship Index, South Korea tops the region in entrepreneurship environment. Among the list of criteria, South Korea dominates in the ease of starting a business and enforcing contracts. They all play a significant role in encouraging investment, production, communication, and, eventually, economic growth. Finally, this paper suggests forward-looking developments promoting transformation and diversification into high-tech manufacturing and digital and green technologies.

Development of Monthly Hydrological Cycle Assessment System Using Dynamic Water Balance Model Based on Budyko Framework (Budyko 프레임워크 기반 동적 물수지 모형을 활용한 월 단위 물순환 평가체계 개발)

  • Kim, Kyeung;Hwang, Soonho;Jun, Sang-Min;Lee, Hyunji;Kim, Sinae;Kang, Moon Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.64 no.2
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    • pp.71-83
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    • 2022
  • In this study, an indicator and assessment system for evaluating the monthly hydrological cycle was prepared using simple factors such as the landuse status of the watershed and topographic characteristics to the dynamic water balance model (DWBM) based on the Budyko framework. The parameters a1 of DWBM are introduced as hydrologic cycle indicators. An indicator estimation regression model was developed using watershed characteristics data for the introduced indicator, and an assessment system was prepared through K-means cluster analysis. The hydrological cycle assessment system developed in this study can assess the hydrological cycle with simple data such as land use, CN, and watershed slope, so it can quickly assess changes in hydrological cycle factors in the past and present. Because of this advantage is expected that the developed assessment system can predict changes in the hydrological cycle and use an auxiliary tool for policymaking.

A Basic Research on the Streetscape in Rural Town Around Large Cities - Focused on 10 Small Towns near Gwangju Metropolitan City - (대도시 주변 면소재지 중심가로 경관분석을 위한 기초 연구 - 광주광역시 인근 10개 소재지를 중심으로 -)

  • Kim, Young Tae;Cho, Tong Buhm
    • Journal of Korean Society of Rural Planning
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    • v.28 no.2
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    • pp.11-20
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    • 2022
  • As a portal to rural town, Myeon near large cities is expected to represent image of the rural area. But, the landscape are changing rapidly due to development pressure and to the expansion of the transportation network. For visitors and transit traffic, Recognizing that the characteristics of the streetscape is an important task for the vitalization of the rural district. In particular, it was found that the visual quantity of the central street in the location of the town was closely related to the preference of the streetscape, and the visual quantity of trees and the visual quantity of the building showed an inverse relationship of + and - respectively. Since this is not a simple ratio of the sky to the building, but a relative factor, the possibility of landscape improvement can be improved through management of public facilities or green spaces and maintenance of open spaces or gaps between buildings. It seems that it is necessary to secure separate means for the management of the architectural landscape, such as the establishment of a special landscape plan or establishment of ordinances.

Economic Analysis Study on the R&D Effect of Performance Improvement of the Tri-generation Fuel Cell System (연료전지 삼중열병합 시스템의 성능개선 R&D 효과에 대한 경제성 분석 연구)

  • Ahn, Jong-Deuk;Lee, Kwan-Young;Seo, Seok-Ho
    • New & Renewable Energy
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    • v.18 no.2
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    • pp.26-39
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    • 2022
  • Considering the recent substantial increase in national research and development (R&D) budgets in the energy sector there has been increased Interest in the effectiveness of government R&D investments. We conducted a case study to calculate the allowable scale and effectiveness of R&D investment by calculating the direct performance improvement effect resulting from R&D investment as an economic value. Using conditions that existed prior to R&D investments as a reference, five cases in which performance improved due to R&D investments were compared and analyzed. The government's financial investment is increasing rapidly in line with the establishment of the national hydrogen roadmap. R&D is needed to enhance the current low technology readiness level of hydrogen fuel cells compared to solar and wind energy fields. Therefore, an R&D project to improve the performance of the fuel cell system was selected as this case study's subject. Using the results in this study, the allowable level of investment in the task unit of national R&D projects could be calculated. Moreover, it is advisable to provide a standard for rational decision making for new R&D investments since it is possible to determine investment priorities among a large number of candidates.