검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 27

        1.
        2024.07 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Photocatalytically splitting water into hydrogen upon semiconductors has tremendous potential for alleviating environmental and energy crisis issues. There is increasing attention on improving solar light utilization and engineering photogenerated charge transfer of TiO2 photocatalyst because it has advantages of low cost, non-toxicity, and high chemical stability. Herein, oxygen vacancies and cocatalysts (Cu and MoS2) were simultaneously introduced into TiO2 nanoparticles from protonic titanate by a one-pot solvothermal method. The composition and structure characterization confirmed that the pristine TiO2 nanoparticle was rich in oxygen vacancies. The photocatalytic performances of the composites were evaluated by solar-tohydrogen evolution test. The results revealed that both Cu-TiO2 and MoS2- TiO2 could improve the photocatalytic hydrogen evolution ability. Among them, 0.8% Cu-TiO2 showed the best hydrogen evolution rate of 7245.01 μmol·g−1·h−1, which was 3.57 and 1.34 times of 1.25% MoS2- TiO2 (2726.22 μmol·g−1·h−1) and pristine TiO2 material (2028.46 μmol·g−1·h−1), respectively. These two kinds of composites also had good stability for hydrogen evolution. Combined with the results of photocurrent density and electrochemical impedance spectra, the incorporation of oxygen vacancies and cocatalysts (Cu and MoS2) could not only enhance the light-harvesting of TiO2 but also improve the separation and transfer capabilities of light-induced charge carriers, thus promoting water splitting to hydrogen.
        4,600원
        2.
        2024.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To reduce production cost and inhibit the aggregation of graphene, graphene oxide and copper nitrate solution were used as raw materials in the paper. Cu particles were introduced to the graphene nanosheets by in-situ chemical reduction method in the hydrazine hydrate and sodium hydroxide solution, and the copper matrix composite reinforced with Cu-doped graphene nanosheets were fabricated by powder metallurgy. The synthesized Cu-doped graphene was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The relative density, hardness, electrical conductivity and tensile strength of the copper matrix composite reinforced with Cudoped graphene were measured as well. The results show that copper ions and graphene oxide can be effectively reduced by hydrazine hydrate simultaneously. Most of oxygen functional groups on the Cu-doped graphene sheets can be removed dramatically, and Cu-doped graphene inhibit the graphene aggregation effectively. Within the experimental range, the copper matrix composites have good comprehensive properties with 0.5 wt% Cu-doped graphene. The tensile strength and hardness are 221 MPa and 81.6 HV, respectively, corresponding to an increase of 23% and 59% compared to that of pure Cu, and the electrical conductivity reaches up to 93.96% IACS. However, excessive addition of Cu-doped graphene is not beneficial for the improvement on the hardness and electrical conductivity of copper matrix composite.
        4,200원
        3.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Graphene exhibits high carrier mobility and concentration as well as other remarkable properties. Among them, the thermal behaviors of phonon modes play important roles in the application of optical and electronic devices. Here, A–A stacked graphene were proved well by Raman investigation on G and 2D modes. Temperature-dependent Raman scattering measurements on graphene with various number of layers on different substrates were conducted in the temperature range of 80–460 K. The first-order temperature coefficient of single layer graphene (SLG) on SiO2/ Si substrate is obviously smaller than that on Cu foil, indicating that the substrate effect attributes a great impact on graphene phonon temperature dependence. The first-order temperature coefficients of multilayer graphene linearly decrease as the number of layers increases, attributed to the reduction of substrate effect in phonon behaviors, rather than to the anharmonic phonon–phonon (ph–ph) coupling or thermal expansion.
        4,000원
        4.
        2020.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In aluminum electrolysis, sodium penetration into carbon cathodes is considered as the main cause of cell failure and efficiency loss, but the detailed mechanism is still not definitely clear. Since the macroscopic properties of material depend on the microscopic structures, a large-scale atomistic model of anthracite cathodes was constructed to represent several important structural characteristics. Combined with Monte Carlo and molecular dynamics simulations, the adsorption and diffusion behaviors of sodium were investigated, respectively. The results suggest that sodium adsorption mainly occurs in the larger micro-pores with the range of 10–19 Å, while it accords well with to type-I Langmuir adsorption model. The sodium is found to be preferentially adsorbed in arch-like structures with 5- or 7-membered rings or around heteroatom, especially oxygen. Moreover, the movements of sodium through carbon matrix mainly depend on the continuous diffusive motion while most sodium particles tend to be trapped in voids with small mobility. The calculated transport diffusion coefficient is equal to 6.132 × 10− 10 m2/ s, which is in outstanding agreement with experimental results. This fundamental research would contribute to the understanding of sodium penetration mechanism and the optimization of cathode industry in the future.
        4,200원
        5.
        2020.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Carbonaceous materials are considered as potential adsorbents for organic dyes due to their unique structures which provide high aspect ratios, hydrophobic property, large efficient surface area, and easy surface modification. In this work, graphene nanoribbons (GNRs) were prepared by atomic hydrogen-induced treatment of single-walled carbon nanotube (SWCNTs), which inspire the idea of cutting and unzipping the SWCNTs carpets with the modified in molecules prevent because of the unfolding of the side-walls. The unfolded spaces and uniform vertical arrangement not only enhance the active surface area, but also promote the electrostatic and π–π interactions between dyes and GNRs. The improved adsorption capacity of GNRs beyond original SWCNTs can be determined by the adsorption kinetics and isotherm, which are evaluated through adsorption batch experiments of the typical cationic methylene blue (MB) and anionic orange II (OII) dye, respectively. It is shown that the adsorption kinetics follow a pseudo second-order model while the adsorption isotherm could be determined by Langmuir model. The results reveal that the maximum adsorption capacities of GNRs for MB and OII are 280 and 265 mg/g, respectively. The GNRs present the highly efficient, cost effective, and environmental friendly properties for the commercial applications of wastewater treatment.
        4,000원
        6.
        2018.11 KCI 등재 구독 인증기관·개인회원 무료
        The legacies of Tokyo Trial have been overlooked and questioned partly because prosecuting aggression was allegedly a violation of the principle of legality. This essay argues that the trial should not be overlooked for this reason because the legality debate at the trial provides insights into the interplay between the principle of legality and sources of international criminal law. Besides the majority judgment, some minority opinions could shed light on the nature of the Tokyo Charter by distinguishing between jurisdiction and applicable law and link the issue to the legality challenge. Although the Tokyo Charter was formally different from the Nuremberg Charter, both of them are substantive in nature so that the tribunals were allowed not to address the legality challenge. In addition, prosecuting aggression was arguably not a violation of the principle of legality because this principle, at that time, did not bind ex post facto legislation against international crimes committed during World War II.
        7.
        2018.07 구독 인증기관·개인회원 무료
        The restaurant industry is more engaged in innovation now. Many entrepreneurs realized that the restaurant sector faces major challenging market environments: changing needs of customers, high competition, low barriers to entry, high labor costs, and innovation technology. The market orientation drives business learning about customers. Engaged customers can assist firms to improve performance by getting involved with the firm’s product innovation. Innovation could help restaurants to improve the products and service quality, cut costs, increase sales and profits; it is the basic condition for the survival of restaurant entrepreneurs. However, studies about how the innovation affects restaurant performance were still limited to describe the overview of products innovation process (Ivkov et al., 2016). Resource-based theory takes the internal resources and capabilities of a firm as valuable sources of competitive advantage. How to combine internal resources and quickly respond to market needs to create performance of innovation entrepreneurship that still unclear and worth exploring in depth discussion. Based on the above, This study personal interview with twelve restaurant entrepreneur, government experts and scholars reveal how absorptive capacity could strengthen the link between positional advantage and innovation for entrepreneurship restaurants with the influence of customer engagement. The positional advantages can make enterprise differentiate with their competitors, that including entrepreneurial orientation, human capital and market orientation (Jogaratnam,2017). The experts believe that innovation entrepreneurs need to adopt an open mind, seek new opportunities in the catering market, acquire or develop new technologies and launching new products / services in the market, using high returns and high risk strategies in search of success in market. Training and educating team members are effective way to improve their innovation entrepreneurship.
        8.
        2018.07 구독 인증기관·개인회원 무료
        As Internet use has increased, customers have become more active at sharing their travel opinions through social media regarding their experiences with service organizations. Social media has become a ubiquitous tool that enables customers to share their travel experiences. In particular, members of Generation Y are more likely to be active on social media and more likely to share their experiences online. Understanding Generation Y’s online customer engagement preferences on different social media platforms may help to enhance brand loyalty. Customer engagement (CE) has been attracting the attention of both practitioners and academics because it may help to enhance both brand loyalty and purchase decisions. Social media platforms have become a significant communication tool for both customers and service providers, creating an opportunity to engage with customers. Interacting with active customers on the right social media platform can increase direct bookings, building brand loyalty. Therefore, the purpose of this research is to examine Generation Y’s brand loyalty preferences through its members’ engagement with social media. The results of this research will expand understanding of Generation Y customers’ online engagement through social media. This research may also suggest how hotels are able to utilize social media platforms in order to encourage online engagement with Generation Y by building brand loyalty.
        9.
        2018.02 구독 인증기관 무료, 개인회원 유료
        In recent years, China initiated Big Data strategies and put forward a series of legislative proposals with regard to the regulation and utilization of Big Data technology. However, academics have not reached consensus to fundamental questions such as data ownership and protection approaches yet. The intrinsic contradiction lies in the difference of values between Big Data which emphasizes “open and sharing” and intellectual property law that protects monopoly interests. This article seeks to conceptualize Big Data in a dynamic approach with an aim to frame the dialogue for further discussion. Through analyzing whether current intellectual property laws in China serve a solid base for promoting the development of big data technology, it proposes that, in order to address regulatory impracticality of Big Data, certain statutory amendments are necessary. However, regarding the revolutionized proposition of creating a “database right” or alleging “Big Data as an object of intellectual property law,” this research recommends a modest and restrained approach.
        6,400원
        10.
        2016.07 구독 인증기관·개인회원 무료
        Scholars have described compulsive behaviour as “hyperstimulation, sometimes unintentional and repeated overindulgence despite negative consequences, deception and self-neglect” (Hartston 2012). Compulsive buying behaviour has become an addiction amongst many consumers and it has fuelled the growth of the retail market since the 1990’s (Neuner, Raab and Reisch 2005; Koran et al. 2006). The higher spending power of the middle-class consumer has led to a greater demand of luxury branded products so that consumers can attain a higher level of social class within the society. This study will explore the impact of emotional factors (self-esteem, FOMO, brand prestige, and brand consciousness) and rationale factors (product quality, price consciousness and sale proneness) on compulsive buyer’s purchase intention. This is the first study to explore the impact of emotional and rationale factors on compulsive buying behaviour in the luxury branded product category. The results show that young consumers with high compulsive buying tendencies are more heavily influenced by emotional factors. Therefore, retailers could target young consumers by focusing on brand prestige and the brand name.
        11.
        2015.12 구독 인증기관 무료, 개인회원 유료
        The antioxidant capacities, total phenolic contents (TPC), and total quercetin contents (TQC) of a red (Chenjujuck), a yellow (Sunpower), and a white (Grasier) onion cultivar were determined in this study. Onion was separated into edible portion and dry skin. In the case of edible portion, the yellow onion had the highest antioxidant activity, followed by the red onion. The white onion showed neither antioxidant activity nor quercetin compounds. On the other hand, the dry skin of the red onion showed higher antioxidant activity than yellow onion skin. The white onion skin had slight antioxidant activity, low TPC, and no quercetin compounds. In addition, the flavonoid compounds of the edible portion and dry skins of these colored onions were analyzed by UFLC(ultra-fast liquid chromatography). The major compounds were quercetin 3,4-diglucoside and quercetin 4- glucoside in yellow and red onion edible portion, whereas the major compounds in yellow and red onion skins were quercetin 4- glucoside, quercetin, and quercetin 3,4-diglucoside.
        4,000원
        12.
        2015.06 구독 인증기관·개인회원 무료
        Increasing attention has been paid to marketing and consumer behavior of luxury industry but research into value creation network and operational mechanisms is very limited. This study focuses on two aspects of the luxury industry: luxury brand and value chain, to inform a comprehensive understanding of the value creation process for high value added brands. In luxury industry, the key elements that create and deliver value are brand, design and research, production, distribution, and retail. A clear brand identity is found as the first step of this value chain, which influences the choices of all other activities. Luxury goods companies will align all the activities in line with brand identity to deliver consistent tangible and intangible values to end users. Furthermore, a luxury value chain is a holistic network with strong coordination among its elements. A combined approach of case study and secondary data collection is pursued. A sample of 9 luxury companies within 6 selected industries is investigated. Data is qualitatively collected via semi-structured interviews, document analysis, and observations as a triangulation approach for the purpose of ensuring the reliability of the research data. Multiple interviews of the general manager, industrial manager, brand/communication manager, creative director, and store manager are conducted in each company to achieve a broader perspective and also make data triangulation procedures possible. This research contributes to the luxury brands management as well as value chain concept. It discusses the value creation network and operational mechanism from a less explored corporate perspective. It unveils a secretive existence of brand in value generation process and further establishes a model to amplify the relationship between each activity in the value chain. Also, it expands the research of value chain into luxury industry. It argues that a supply leading value chain can also command a premium rather than the customer-centric value chain discussed by most researchers recently. It also provides valuable insights for companies who want to have a high-end market position. It shows that the widely adopted luxury strategy invented mainly by French and Italian companies employs fundamentally different rules from those of fast-moving consumer goods in mass market. In short, a luxury strategy is different in nature, not in level.
        14.
        2013.06 구독 인증기관 무료, 개인회원 유료
        For more than two decades, the intracytoplasmic sperm injection (ICSI) technique has been used as a valuable tool to provide opportunities for studying fertilization, treating human infertility, and producing transgenic animals. Not only in facilitating fertilization but also in propagating mammalian species, ICSI has enhanced the potential of assisted reproductive technologies in human. Polyspermic fertilization has been one of major problems in pig reproduction, but the ICSI helped to solve the problem, and used widely to generate transgenic piglets. Although the ICSI technique is considered to be a very useful tool in assisted reproductive technologies, including generation of transgenic animals, there are some disadvantages using the technique. In this review, we describe the ICSI technique and its application in animal production and human infertility, and discuss advantage and disadvantage of the technique in mammals.
        4,000원
        15.
        2012.06 구독 인증기관·개인회원 무료
        The objective of this study was to investigate the effects of NEAA and leptin supplemented to in vitro culture medium on the developmental competence of porcine embryos after intracytoplasmic sperm injection (ICSI), and to modify the culture condition to improve the quality and the development of ICSI-derived porcine embryos in vitro. After ICSI, the putative zygotes were then cultured in PZM-3 medium with/without NEAA or leptin. The proportion of embryos that developed to the blastocyst stage significantly increased when 1% NEAA (24.62%) was added to the medium compared with 2% NEAA and no NEAA group (17.24% and 20.24%, respectively, p<0.05). The effect of different concentration of leptin (0, 10, 100, 500 ng/ml) was evaluated on the development of porcine ICSI embryos cultured in vitro. In case of blastocyst formation, 100 ng/ml group (27.05%) showed significantly higher rate than 10, 500 ng/ml, and control group (23.45%, 17.99%, and 19.68%, respectively, p<0.05). We also evaluated the effects of different NEAA and leptin treatment time on the development of porcine embryos after ICSI. Among groups of embryos cultured in the presence of NEAA or leptin for whole 7 days (D 1-7), first 4 days (D 1-4), the subsequent 3 days (D 5-7), both NEAA (27.13%, 21.17 %, and 17.56%, respectively, p<0.05) and leptin (25.60%, 20.61%, and 16.53%, respectively, p<0.05) showed that supplementation for whole 7 days significantly increased the blastocyst formation rate compared with the other groups of D1-4 and D5-7. We further evaluated the combination effect of 1% NEAA and 100 ng/ml leptin compared with the effect of each supplementation with 1% NEAA or 100 ng/ml leptin or no supplementation on development of embryos. For blastocyst formation, combination group of NEAA and leptin (24.78%) showed significantly higher rate than other three groups (18.37%, 20.44 %, and 13.27%, respectively, p<0.05). We further evaluated the expression of proapoptosis genes such as BAX and BAK and anti-apoptosis genes, BCL-XL and BCL-2 in blastocysts cultured in the presence of 100 ng/ml leptin. RT-PCR analysis revealed that leptin supplementation significantly decreased the expression of pro-apoptosis genes as well as increased the expression of anti-apoptosis genes. These results of present study demonstrate that NEAA and leptin could improve the in vitro development of ICSI- derived porcine embryos with optimal concentration of each reagent. Furthermore, the optimal culture condition could increase the quality of ICSI-derived embryos in vitro.
        16.
        2006.09 구독 인증기관·개인회원 무료
        Warm compaction powder metallurgy was used to produce a Ti3SiC2 particulate reinforced Cu matrix composite. Fabrication parameters and warm compaction behaviors of Cu powder were studied. Based on the optimized fabrication parameters a Cu-based electrical contact material was prepared. Results showed that in expend of some electrical conductivity, addition of Ti3SiC2 particulate increased the hardness, wear resistivity and anti-friction ability of the sintered Cu-base material.
        17.
        2006.09 구독 인증기관·개인회원 무료
        The introduction of ceramic particulate into metallic powder will unavoidably lower the compressibility and formability of the mixed powder. In this study, warm compaction, which is a simple and low cost technique to produce high density PM parts, was introduced in preparing composite. The aim of this paper is to prepare the warm compacted NbC particulate reinforced Fe-based composite, then study its tribological behavior and application in the valve-guide cup. A 15 wt.% NbC reinforced iron-based composite was prepared. It possesses a relative density of 98%, a tensile strength of 515 MPa, a hardness of HRC 58 and a remarkable tribological behavior.
        18.
        2002.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The surface treatment of C-type isotropic pitch-based carbon fiber was carried out by anodic oxidation in 5 wt% NH4NO3 electrolyte. The changes of fiber surface and carbon fiber/ABS resin composites were characterized by SEM, XPS and mechanical properties test. The oxygen functional groups on the surface, such as hydroxyl (-C-OH), carboxyl (-COOH) groups etc., increased after oxidation. Tensile strength, flexural strength and modulus of carbon fiber/ABS composites were also enhanced. However, the impact strength decreased with the improvement of the surface adhesion between CF and matrix.
        4,000원
        19.
        2023.11 서비스 종료(열람 제한)
        The signing and implementation of RCEP mark the birth of a highly promising free trade zone. This agreement not only promotes the liberalization of regional trade and investment, creating an integrated regional market but also drives regional economic growth, supporting the stability and prosperity of the East Asian economic sphere. Simultaneously, it contributes to global economic recovery.The implementation of RCEP brings new development opportunities to China’s manufacturing industry but also imposes higher standards, stricter rules, and intensified competition. Chinese manufacturing will face more challenges. This article analyzes the opportunities and challenges brought by RCEP to China and proposes policy suggestions to promote the development of China’s manufacturing industry, including strengthening cooperation with RCEP countries, enhancing technological innovation capabilities, and prioritizing the development of the workforce.
        20.
        2019.09 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 중지역 특성, 유리한 자원 및 산업 레이아웃 등에 따라 하이난의 복숭아 정원 공유 농장의 계획 및 설계를 예로 들어 계획의 적용에 대해 연구 분석한다. 연구 분석은 정책 기반, 농촌 활성화 철학, 건설 판매 및 건설 내용과 같은 측면과 연구는 분석 및 요약을 통해 수행하였다. 하이난 도화원 프로젝트는 먼저 국가 산업 정책을 준수하고 산업 통합 및 개발을 촉진한다. 둘째, 1 차 산업과 2 차 산업을 완전히 주도하고, 3차 산업을 보다 강력하고 긍정적으로 만들어 농촌 경제 발전에 도움이 되고, 농민들이 서비스 산업과 가공 산업으로 전환하고, 농촌 재 활성화에 이르게 할 수 있는 결론을 도출하였다.
        1 2