• Title/Summary/Keyword: time dependence

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A Study on the User's Response to the Flight Action in 3D Game -Focused on 3D MMORPG Aion- (3D 게임에서 '비행' 행위에 대한 사용자의 반응 연구 -3D MMORPG Aion을 중심으로-)

  • Bae, Kyoung-Mi;Kim, Kyu-Jung;Kim, Inseop
    • Journal of Korea Game Society
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    • v.12 no.6
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    • pp.33-46
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    • 2012
  • This research aimed to analyze the way of how flying movement system and background graphic in MMORPG, which provides movement system, influences on users' psychological behavior in order to enhance user's participation and the completion level of 3D game. This research also analyzed the difference between the user's response to the flying movement and other movement structure in game such as things to board, summons, portal, chase, and etc. With this comparative analysis, this study could clarify the characteristics of the user's desire to fly according to the virtual world' topography in game, the necessity of flying movement for fast movement, the dependence of user on flying system, the immersion according to behavior in process of flying, and expression level of virtual world, and etc. The survey through the case research of MMORPG Aion selected for this research showed flying movement system can have suitable quality by applying users' playing time and absorption in flight process, users' impulse following game level, and users' need to fly as a convenience of flying properly.

Improved Preservation and Shelf-life Extension of Fish Cake by Modified Atmosphere Packaging (변형기체포장에 의한 어묵의 저장성 향상 및 유통기한 연장)

  • Park, Su Yeon;An, Duck Soon;Kang, Jun Soo;Lee, Dong Sun
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.23 no.2
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    • pp.75-81
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    • 2017
  • Modified atmosphere packaging (MAP) of vacuum, 60% $N_2/40%$ $CO_2$, 100% $N_2$ and 100% $CO_2$ were examined to preserve fried fish cakes and extend their shelf life. When product packages in air were stored at 5, 10, and $15^{\circ}C$ with measurement in quality attributes, aerobic bacterial growth was found to be primary quality factor to determine the shelf life of the product. Huang's model was adopted to obtain the parameters for use in shelf life determination for a variety of packaging and storage conditions. Temperature dependence expressed in Arrhenius equation showed activation energies of 139.4 and 41.8 kJ/mol for inverse of lag time and growth rate of the microbial spoilage, respectively. MAP of 100% $CO_2$ could double the product shelf life at $10^{\circ}C$ compared to air package. High $CO_2$ concentration MAP at low temperature was found to be effective to prolong the shelf life.

Synthesis and Lubricant Properties of Estolides based on Fatty Acid (지방산 기반 에스토라이드 합성 및 윤활특성)

  • Son, Jeong-Mae;Yoo, Seunghyun;Lee, Sangjun;Shin, Jihoon;Chung, Kunwo;Yang, Youngdo;Kim, Young-Wun
    • Tribology and Lubricants
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    • v.30 no.5
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    • pp.256-264
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    • 2014
  • Enhancing the value of fine chemicals based on biomass resources is an important objective for addressing environmental and other concerns such as demand for renewable or green products, as well as from the political perspective to reduce dependence on fossil feedstock associated with the use of petroleum-based products. Based on these considerations, we studied the synthesis of estolide using waste plant-based oil materials and their application as lubricants and pour point depressants. Five estolides were prepared by varying molar ratio of palmitic acid (PA) to oleic acid (OA) using a reaction time of 48 h. The estolides were characterized by size exclusion chromatography (SEC) and nuclear magnetic resonance (NMR). The isolated yields were in the range of 57-78 % and purity was 93-97%, showing iodine values of 18.2-37.8, total acid numbers (TANs) of 75.6-94.2 mg KOH/g and estolide numbers (ENs) of 1.2-1.8. Increasing the ratio of OA to PA in the synthesis decreased the kinematic viscosity and clouding point of the estolides. Four ball wear test of the estolides as a base oil demonstrated that the wear scar diameter (WSD) of the estolides was significantly lower (0.320-0.495 mm) than the WSD of general base oils such as 150N and Yubase (0.735 and 0.810 mm, respectively), indicating better wear resistance of the estolides. However, the lubricant property was found to be independent of the amount of OA in the estolides. These new materials are prospective candidates for application as a lubricant base oil.

Resistance to ACCase Inhibitor Cyhalofop-butyl in Echinochloa oryzicola Collected in Gyeongsangnam-do Province of Korea (ACCase 저해 제초제 cyhalofop-butyl에 대한 경남지방 수집종 피의 저항성)

  • Won, Jong Chan;Won, Ok Jae;Ha, Jun;Im, Il-Bin;Kang, Kwang Sik;Pyon, Jong Yeong;Park, Kee Woong;Lee, Jeung Joo
    • Weed & Turfgrass Science
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    • v.7 no.2
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    • pp.166-169
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    • 2018
  • Repeated use of ACCase inhibiting herbicides for a long time has resulted in increases of resistant Echinochloa oryzicola populations in paddy fields in middle west area of Korea. This study aims to investigate current status of herbicide resistant E. oryzicola in Gyeongsangnam-do, in which there is less information about herbicide resistance. For resistance frequency and dose-response study, seeds from 100 individual plants of E. oryzicola in Gyeongsangnam-do were collected and tested with cyhalofop-butyl. Seven percent of plants from Gyeongsangnam-do was resistant at a recommended rate of cyhalofop-butyl. $GR_{50}$ values (herbicide rates required to reduce plant growth 50%) for one representative resistant populations and five susceptible populations were $738g\;a.i.\;ha^{-1}$ and 66-234 (average 147)$g\;a.i.\;ha^{-1}$, respectively, indicating average 5 times difference in resistance. Although lower rate of frequency of herbicide resistance in Gyeongsangnam-do than in Jeollabuk-do, increases of herbicide resistance are expected in this area because of increases of direct seeded rice fields and increases of dependence on a specific herbicide. Therefore, it is necessary to monitor herbicide resistance regularly and conduct integrated herbicide resistance management in this area.

Smartphone Usage Experience of College students (대학생들의 스마트폰 사용 경험)

  • Kim, Jungae;Cho, Eui-young
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.3
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    • pp.187-201
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    • 2016
  • The purpose of this study was to analyze the smart phone usage experience structure for college students. The phenomenology approach was used by conducting 4 times in-depth interviews with the 7 college students age between 20~23. Collected Data was analyzed by Giorgi's phenomenological method. There were 4 general structure descriptions and 28 themes. General structure descriptions were 'Dependence on smart phone', 'Phenomenon of smart phone usage', 'Results of smart phone usage' and 'Relationship between stress and smart phone'. Themes consisted of 'Ambivalence', 'Positive feelings for smart phones', 'Separation anxiety', 'Negative feelings for smart phones'. 'Dependent feelings for smart phones', 'A sense of unity with smart phones', 'Helpful for my life', 'Deeply involved with my life', 'Useful tool in my life', 'Study, communication, relaxation and health care', 'Maintain personal relationship', 'The most important thing in my life', 'Shallow relationship stress', 'Interference with personal relationship', 'Forming a negative relationship', 'Invasion of privacy', 'Forming a Incorrect relationship', 'Unwanted participation', 'No effort to improve relationship', 'Poor concentration', 'Interference with academic study', 'Study assistance', 'Limited help for study in depth', 'Shelter from the stress', 'Amplification of the stress', 'Obsessive focus', 'Feel separation for the reality' and 'Waste of time'. Smart phone usage make college students dependent on smart phones and had negative influence on both personal relationship and academic results. Usage of smart phone also amplified stress. Therefore we need fundamental principles on usage of smart phone and propose to build cultural etiquette that provides reasonable way to use smartphone.

Synthesis of ZnS : Cu nano-crystals and structural and optical properties (ZnS : Cu nano 업자의 합성 및 구조적.광학적 특성)

  • 이종원;이상욱;조성룡;김선태;박인용;최용대
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.12 no.3
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    • pp.138-143
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    • 2002
  • In this study, ZnS: Cu nano-crystals are synthesized by solution synthesis technique (SST). The structural properties such as crystal structure and particle morphology, and the optical properties such as light absorption/transmittance, energy bandgap, and photoluminescence (PL) excitation/emission are investigated. In an attempt to realize the Cu-doping easiness, the synthesis temperature (~$80^{\circ}C$) is applied to the synthesis bath, and the thiourea is used as sulfur precursor, unlike other general chemical synthesis route. Both undoped ZnS and ZnS : Cu nano-crystals have the cubic crystal structure and have the spherical particle shape. The position of light absorption edge is ~305 nm, indicating the occurrence of quantum size effect. The PL emission intensity and line-width are maximum and minimum, respectively, for Cu-doping concentration 0.03M. In particular, the dependence of PL intensity and line-width on the Cu-doping concentration for ZnS : Cu nano-crystals synthesized by SST is reported for the first time in this study. Experimental results of the absorption edge and the PL excitation show that the main emission peak of ZnS : Cu nano-crystals (~510 nm) in this study is due to the radiative recombination center in the energy bandgap induced by Cu dopant.

Dental Practitioners Self Reported Performance of Tobacco Cessation Counseling Interventions: A Cross Sectional Study

  • Parakh, Abhinav;Megalamanegowdru, Jayachandra;Agrawal, Rohit;Hathiwala, Siddhi;Chandrakar, Mayank;Tiwari, Ram;Veeranna, Thippeswamy
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.6141-6145
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    • 2013
  • Background: The objective of the study was to determine the knowledge, attitude and behaviors of the practicing dentists regarding tobacco cessation counseling (TCC) in Chhattisgarh state and also the barriers that prevent them from doing so. Materials and Methods: The study was conducted among dental practitioners of Raipur district, Chhattisgarh state (India). The sampling frame was registration with the State Dental Council and practicing in Raipur district. A questionnaire was personally administered and the practitioners were given explanations regarding how to complete it. Only descriptive statistics were calculated (SPSS version 16 for Windows). Results: Based on the responding dentists' self reports, 76% were not confident in TCC, 48% did not assume TCC to be their responsibility, 17% considered that it might have a negative impact on their clinical practice, whereas 24% considered it might take away precious time from their practice, 25% considered TCC by dentists to be effective to a considerable extent and 80% considered TCC activities are not effective due to lack of formal training, 69% considered dental clinics as an appropriate place for TCC but 82% thought there must be separate TCC centre and 100% of the dentists wanted TCC training to be a part of practice and that it should be included in dental curriculum. Some 95% of them were of the view that tobacco products should be banned in India and 86% responded that health professionals must refrain from tobacco habits so to act as role models for society. Conclusions: Dental professionals must expand their armamentarium to include TCC strategies in their clinical practice. The dental institutions should include TCC in the curriculum and the dental professionals at the primary and the community health care level should also be trained in TCC to treat tobacco dependence.

Energy Density Control for the Global Attenuation of Broadband Noise Fields (광대역 잡음의 전역 감쇠를 위한 에너지 밀도 제어)

  • Park, Young-Cheol;Yun, Jeong-Hyeon;Youn, Dae-Hee;Cha, Il-Whan
    • The Journal of the Acoustical Society of Korea
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    • v.15 no.2
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    • pp.21-32
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    • 1996
  • The performance of the energy density control algorithm for controlling a broadband noise is evaluated in a one-dimensional enclosure. To avoid noncausality problem of a control filter, which often happens in a frequency domain optimization, analyses presented in this paper are undertaken in the time domain. This approach provides the form of the causally constrained optimal controller. Numerical results are presented to predict the performance of the active noise control system, and indicate that imp개ved global attenuation of the broadband noise can be achieved by minimizing the energy density, rather than the squared pressure. It is shown that minimizing the energy density at a single location yields global attenuation results that are comparable to minimizing the potential energy. Furthermore, unlike the squared pressure control, the energy density control does not demonstrate any dependence on the error sensor location for this one-dimensional field. A practical implementation of the energy-based control algorithm is presented. Results show that the energy density control can be implemented using the two sensor technique with a tolerable margin of performance degradation.

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Synthesis and Characterization of Biodegradable MethoxyPoly(ethylene glycol)-Poly$(\varepsilon-caprolactone-co-L-lactide)$ Block Copolymers (메톡시폴리(에틸렌 글리콜)-폴리(카프로락톤-co-L-락타이드) 공중합체의 합성 및 특성 분석)

  • Hyun Hoon;Cho Young Ho;Jeong Sung Chan;Lee Bong;Kim Moon Suk;Khang Gilson;Lee Hai Bang
    • Polymer(Korea)
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    • v.30 no.1
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    • pp.28-34
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    • 2006
  • A series of methoxypoly(ethylene glycol) $(MPEG)-poly(\varepsilon-co-L-lactide)$ (PCLA) diblock copolymers were synthesized by ring-opening polymerization of a mixture of $\varepsilon-caprolactone$ and L-lactide with different ratios in the presence of $Sn(Oct)_2$. The characterization of MPEG-PCLA diblock copolymers were examined by $^1H-NMR$, GPC, DSC, and XRD. Kinetic study on ring-opening polymerization of monomer mixtures was carried out in various conditions such as a variation with polymerization time, amount of catalyst, and temperature. The highest conversion obtained in 1.2 ratic of initiator venn catalyst at $110\;^{\circ}C$. The biodegradable characterization of MPEG-PCLA diblock copolymers in aqueous solution was carried out by using GPC for $1\~14$ weeks. The biodegradability of MPEG-PCLA diblock copolymers increased as the L-lactide content of diblock copolymers increased. In conclusion, we confirmed the dependence of polymerization rate according to various conditions. In addition, we can control the biodegradability of MPEC-PCLA diblock copolymers by changing the ratio of PCL and PLA block segment.

Impact of Internal Marketing Factors on Technological Innovation and Perceived Service Quality in Telecommunications (내부마케팅 요인이 조직의 기술혁신과 지각된 서비스 품질에 미치는 영향)

  • Jung, Gap-Jin;Hwang, Hee-Joong;Song, In-Am
    • Journal of Distribution Science
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    • v.13 no.6
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    • pp.87-96
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    • 2015
  • Purpose - Several domestic telecommunication companies have made a considerable effort to continuously grow and survive, and they have strived to thrive in the midst of mature market competition. To overcome this challenging situation and to grow continuously, while still meeting customer needs that are becoming more diverse and complicated with the passage of time, extensive support for internal marketing is essential. Without such internal support, companies face serious limitations and market roadblocks. The communication industry is a high-level service industry and a basic communications industry characteristic is its significant dependence on the employees delivering the services. Therefore, entrepreneurs in the information/communications industry, as well as existing competitors, should look to satisfy external customers through critical investment in internal customers (employees). Therefore, it is important for research to examine how internal factors influence technology innovation and service quality, which are the key drivers for companies that are seeking leading market positions. Research design, data, and methodology - The purpose of this study is to analyze the relationship of technology innovation and perceived service quality with the internal marketing factors in the communication industry and to offer suitable and effective internal marketing suggestions. The independent variables of this study are internal communication, education and training, the support of the executives, reward systems, and empowerment. The dependent variables are technology innovation and perceived service quality. Utilizing these, this paper studies the influence of internal marketing factors on technology innovation and perceived service quality. Results - The study results revealed the following. First, the identified internal marketing factors have a positive effect on technology innovation. Among the five internal marketing factors, three had a significant effect on product innovation, empowerment, the support of executives, and education and training, in this order. Second, the internal marketing factors also had a positive effect on the process innovation of technology innovation. The marketing factors, the support of executives, empowerment, internal communication, and education and training, in this order, significantly affect process innovation. Third, technology innovation had a positive effect on perceived service quality. All of the five service quality factors, namely, tangibles, reliability, assurance, responsibility, and empathy, in this order, significantly affect product innovation. Additionally, tangibles, reliability, responsibility, empathy, and assurance, in this order, significantly affect process innovation. Fourth, product and process innovation significantly affect tangibles and reliability in technology innovation. To enhance tangibles and reliability, process innovation should first be enhanced. Fifth, product and process innovation significantly affect responsibility and empathy in technology innovation. To enhance the responsibility and empathy, process innovation should first be enhanced. Sixth, product and process innovation significantly affect assurance in technology innovation. To enhance the assurance, product innovation should first be enhanced. Conclusions - According to the results, a company's internal marketing factors have a positive and significant effect on technology innovation and, further, product and process innovation have a positive and significant effect on the perceived serviced quality.