• Title/Summary/Keyword: major elements

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Novel solvothermal approach to hydrophilic nanoparticles of late transition elements and its evaluation by nanoparticle tracking analysis

  • Dutilleul, Marion Collart;Seisenbaeva, Gulaim A.;Kessler, Vadim G.
    • Advances in nano research
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    • v.2 no.2
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    • pp.77-88
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    • 2014
  • Solvothermal treatment of late transition metal acetylacetonates in a novel medium composed either of pure acetophenone or acetophenone mixtures with amino alcohols offers a general approach to uniform hydrophilic metal nanoparticles with high crystallinity and low degree of aggregation. Both pure metal and mixed-metal particles can be accesses by this approach. The produced materials have been characterized by SEM-EDS, TEM, FTIR in the solid state and by Nanoparticle Tracking Analysis in solutions. The chemical mechanisms of the reactions producing nanoparticles has been followed by NMR. Carrying out the process in pure acetophenone produces palladium metal, copper metal with minor impurity of $Cu_2O$, and NiO. The synthesis starting from the mixtures of Pd and Ni acetylacetonates with up to 20 mol% of Pd, renders in minor yield the palladium-based metal alloy along with nickel oxide as the major phase. Even the synthesis starting from a mixed solution of $Cu(acac)_2$ and $Ni(acac)_2$ produces oxides as major products. The situation is improved when aminoalcohols such as 2-aminoethanol or 2-dimethylamino propanol are added to the synthesis medium. The particles in this case contain metallic elements and pairs of individual metals (not metal alloys) when produced from mixed precursor solutions in this case.

Geochemical Characteristics of Surface Sediments in the Keum River Estuary Adjacent to Coastal Area (금강하구 표층퇴적물의 지화학적 특성에 관한 연구)

  • Seo, Man-Seok;Park, Young-Seog
    • Journal of Fisheries and Marine Sciences Education
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    • v.19 no.1
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    • pp.1-7
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    • 2007
  • The purpose of this study was to investigate geochemical characteristics of surface sediments in the Keum river estuary adjacent to coastal area. For this study we collected the 21 surface sediments samples. Mean size of surface samples was $3.24{\sim}6.65{\phi}$ on inner estuary and was $2.15{\sim}3.42{\phi}$ on outside estuary. Surface samples were composed of silt on inner estuary and were composed of sand which was more larger than $4{\phi}$ on outside estuary. Most major elements except CaO, $Na_2O$ showed good relationships between variation of contents and grain size. Contents of $Al_2O_3$, $Fe_2O_3$, MgO, $K_2O$, $TiO_2$, $P_2O_5$ and $M_nO$ were increased predominately owing to the variation of mean size of surface samples. Contents of Co, Cr, Cu, Li, Sr, Zn, La, Ce, Pb, Rb, Nd have a good relationships with grain size but Ba, Th, Sm have not. All of major and minor elements contents except $K_2O$ and Ba were less than world mean contents of shallow surface sediments but apprehend a high pollution possibility on silt sediments in the estuaries.

A Qualitative Study on Factors Related to Job Stress for Fashion Corporation Employees: Focusing on Fashion Manufacturing Companies (패션 기업 근무자들의 직무 스트레스 유발 요인에 관한 질적 연구: 패션제조업체를 중심으로)

  • Rhee, YoungJu
    • Human Ecology Research
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    • v.53 no.4
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    • pp.463-473
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    • 2015
  • The fashion industry has distinctive characteristics. It is important to understand the specific working environment and unique problems at fashion corporations in order enhance employee efficiency. However, studies on job stress for fashion employees remain limited. This study used qualitative research to examine major job stress factors for fashion company workers. In-depth interviews were conducted on 6 respondents who work in various departments at fashion manufacturing companies. We identified task-related factors and structural factors as the two major job stress factors. Task-related factors consisted of 4 elements (necessity of massive knowledge, overtime outside work, tight schedules, and organizational tasks); structural factors consisted of 3 elements (burden of sales outcome, formal relationships, and anxiety of salary retirement). The results indicated that respondents consistently tried to gain knowledge about the latest trends and field experiences that caused mental and physical exhaustion due to the necessity of working late. Designers and workers in the sales department were constantly evaluated by their sales results compared to other workers that caused high levels of stress. Respondents answered that building relationships was an important factor in the fashion industry and sometimes felt that building formal relationships was more important than the ability to do work.

Variation of Chemical Composition and Relative migration of major Elements in the Weathering of Jeon-Ju granite and Rang-San granite (전북(全北) 전주지역(全州地域) 화강암(花崗岩) 및 낭산지역(郎山地域) 화강암(花崗岩)의 풍화(風化)에 따른 화학조성(化學組成)의 변화(變化)와 주요원소(主要元素)의 상대적이동(相對的移動))

  • Nam, Ki Sang
    • Economic and Environmental Geology
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    • v.8 no.4
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    • pp.211-221
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    • 1975
  • Weathering of granites has a geochemical role of great significance, because of their abundance and because of chemical instability near the surface of the earth, which is more pronounced than in most other rocks. On the other hand the granites are tectonically fragile and "react" to deformation with marked facility, giving rise to a whole gamut of deformed rocks. Therefore, the writer has studied on the weathering of granitic rocks at of Iri city and Jeonju city Jeollabukdo, Korea, The fresh and weathered rocks were used as material for the investigation. The results obtained by chemical analysis and observation are as follows. 1) The order of mobility in major elements was Ca, Na and K$H_2O$ was observed clearly and late stages of weathering processes. 3) The early stage of weathering is commenced by physical weathering and followed by chemical weathering. 4) The ratio of FeO/. $Fe_2O_3$, FeO/MgO, and $SiO_2/Al_2O_3 $ decreased uniformly from early to late stage of weathering processes. 5) It was proved that weathering potential of granite was larger than that of basaltic rocks.

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A Study on the Trend of an Avionics System Architecture Development for UAV (무인기 항공전자 체계의 아키텍처 개발 동향연구)

  • Kim, Sung Woo;Sim, Jae Ick;Lee, Wang Gug;Lee, Woo Jin;Won, Dae Yeon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.4
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    • pp.436-447
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    • 2014
  • The major elements of avionics system architecture are requirements, Real Time Operating System, message communication, memory, and data format etc. Herein describes a state-of-the-art development trend for the avionics system architecture, system requirements and data bus among the major elements of avionics system. While, domestic technology has been tried to Integrated Modular Avionics(IMA) system based on the Avionics Full Duplex Switched Ethernet(AFDX) technology during Light Attack Helicopter(LAH) project in Korea, but not yet proved as the product case in Full Scale Development Phase. The avionics system architecture considering the domestic inexperience of the IMA system architecture are suggested for the Next-generation Corps Unmanned Aircraft System.

A Study on Safety Guideline of Level 4 Automated Driving Vehicles (레벨 4 자율주행자동차의 제작 안전 가이드라인에 대한 고찰)

  • Lee, Gwang Goo;Woo, Hyungu
    • Journal of Auto-vehicle Safety Association
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    • v.13 no.3
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    • pp.86-94
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    • 2021
  • Since automated driving system (ADS) has great potential to innovate various fields of automobile and mobility industries, major countries are establishing safety standards for autonomous vehicles to support technology development. However, in order to prevent technology development from being hampered by the safety standards for technologies still under development, safety guidelines are applied until the technologies are mature. For example, the safety 'guideline' for level 4 ADS was published in December 2020 by the Ministry of Land, Infrastructure and Transport of Korea, while the safety 'standards' for level 3 ADS was promulgated in December 2019. In this study, the domestic safety guideline for level 4 ADS is analyzed with the guidelines of major advanced countries in terms of safety elements. As it takes a lot of time before the safety standards of level 4 ADS is introduced, it is expected that the safety guideline will be updated several times. As necessary considerations when updating the safety guideline, industry acceptance, harmonization between safety elements, validation methods of system performance, and the user options are discussed.

The Transmedia Storytelling Strategies of (<마인크래프트: 스토리 모드>의 트랜스미디어 스토리텔링 전략)

  • Jeon, Gyongran;Kim, Young-Chul
    • Journal of Korea Game Society
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    • v.21 no.2
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    • pp.55-66
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    • 2021
  • The research studies how features of games can be utilized and converted into storytelling elements by analyzing specific transmedia storytelling cases. For the research, was selected for subjects of analysis. From the analysis conducted, first, how game can be expanded and transformed into interactive animations was observed. Also, use of representative elements of the original game, concepts and basic settings in was seen. And lastly, implementation of transmedia storytelling strategies that constitute narratives based on character creation and connection between spaces was also observed.

Alkali swelling characteristics of wood elements (목재 구성세포의 알칼리 팽윤 특성)

  • 황원중;김남훈
    • Journal of Korea Foresty Energy
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    • v.20 no.1
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    • pp.62-72
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    • 2001
  • To elucidate the behaviors of alkali swelllng of woods. the dimensional change in cross section of cell elements of four major Korean woods during alkali swelling were examined by an optical microscory, an imaging analysis method and an X-ray diffrartion During alkali swelling, tracheid diameter of Larix kaempferi wood showed greater swelling property than that of Pinus koraiensis wood, and the cell wall swelled highly over 10% sodium hydroxide solution treatment. The radial diameter of vessel elements in earlywood shrunk, but it swelled slightly in tangential direction. When treated with 5% NaOH, the wall thickness of wood fiber increased about three times over the original one. The thickness of cell wall in all elements and the diameter of wood fiber and tracheid showed almost isotropic shrinkage. The diameter of cell elements during the mercerization process decreased, but cell wall thickness Increased. Crystal transformation of cellulose in wood was not occurred by alkali treatments. but relative crystallinity and crystallite width of the woods increased slightly. Consequently, it was demonstrated that the swelling properties of woods were dependant on wood species, cell elements and alkali concentration.

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A Study on Perceptual Characteristics of Facade Design and Composition Elements of Cafe Space (카페공간의 구성요소와 파사드디자인의 지각특성에 관한 연구)

  • Choi, Gae-Young
    • Korean Institute of Interior Design Journal
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    • v.22 no.4
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    • pp.70-77
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    • 2013
  • This study has analysed the composition elements in a cafe space where visual transfer-elements are filled and the perceptual characteristics of facade designs with the purpose of drawing any important elements to advertisement and their related items for uniqueness of designs. For the analysis of the perception process shown in the consecutive situations of observing and visiting cafes, the cafe facade was grouped and stereotyped for the analysis of perceptual characteristics and significant composition elements for better designing of cafes through survey with representative facades as subjects. The conclusions from this study are the followings. First, for the uniqueness specific to cafes to be integrated into facade, memory was chosen first as the most significant advertisement factor followed by interest as with male and attention as with female. The memory has much to do with furniture and finishing material of Clause (4), Chapter 4.1 and the types having effects on perception of Clause (1) and the atmosphere having effect on that of Clause (2) were found to be major factors to attention and interest. Second, it was found out that women preferred horizontally stable partition and men clearly divided facades. The factor of shape was observed first among the constituents of facade followed by color. There was no difference with 'shape' between men and women and color was found to be a space constituent having a lot of effects on women. Third, the memory of experience from visiting a cafe was very likely to offer the motivation of visiting it again, on which furniture had the most effect followed by finishing material and color. Such elevation elements as facade and logo were found not to have effect on the memory or the re-visit. Any intention of visiting again seemed to be influenced by such comprehensive images as atmosphere rather than by any concrete facade, furniture, or appliance. From the above viewpoint, facade design should have any uniqueness or impressive feature as well as the effect of making passers-by drop in and attracting them into the shop. The analysis of attributes of facade constituents revealed that the abstract images in addition to the configuration of facade had much to do with interest or behavior.

Effects of Network Externality on Perceived Value and Adoption of High-tech Products : Focusing on Convergence Products (네트워크 외부성이 첨단기술제품에 대한 가치와 채택의도에 미치는 영향: 컨버전스제품을 중심으로)

  • Park, Kyung Ja
    • The Journal of Information Systems
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    • v.24 no.4
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    • pp.21-42
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    • 2015
  • Purpose The high-technology market shows characteristics of a highly interdependent network market in both supply-side and demand-side, compared to other markets. Particularly, for convergence products, connectivity with related elements, as well as characteristics of innovation itself, is relatively important to the extent that they combine functions provided by several devices into a single device. Therefore, this study aims to identify whether network externality exists in value and adoption of a convergence product and discover a source of network externality, if any. Design/methodology/approach: Through a preceding research analysis and a literature review, 'social influence' and 'network size' have been drawn as direct network elements. On the other hand, general (comprehensive) concept compatibilities including 'intra-technology compatibility', 'inter-technology compatibility' and 'complementary-technology compatibility' are regarded as indirect network elements. Findings: Major findings are as followed;- First, it is shown that the factors influencing on perceived value of a convergence products are 'social influence' and 'network size' as the direct network elements and 'complementary-compatibility' among indirect network elements. Second, it is also found that 'intra-technology compatibility', 'inter-technology compatibility', 'complementary-compatibility' and 'perceived value' have significant effects on adoption of a convergence product. Particularly, it is known that 'complementary-compatibility' is an important source of network externality as it plays a decisive role in value judgment and has significant effects on perceived value. It is worthwhile to notice that this study comprehensively explains effects of network on high-tech products by structuring comparability as a multi-dimensional concept, as well as direct network elements.