• Title/Summary/Keyword: Time gap

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An Exploratory Study on Measuring Brand Image from a Network Perspective (네트워크 관점에서 바라본 브랜드 이미지 측정에 대한 탐색적 연구)

  • Jung, Sangyoon;Chang, Jung Ah;Rho, Sangkyu
    • The Journal of Society for e-Business Studies
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    • v.25 no.4
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    • pp.33-60
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    • 2020
  • Along with the rapid advance in internet technologies, ubiquitous mobile device usage has enabled consumers to access real-time information and increased interaction with others through various social media. Consumers can now get information more easily when making purchase decisions, and these changes are affecting the brand landscape. In a digitally connected world, brand image is not communicated to the consumers one-sidedly. Rather, with consumers' growing influence, it is a result of co-creation where consumers have an active role in building brand image. This explains a reality where people no longer purchase products just because they know the brand or because it is a famous brand. However, there has been little discussion on the matter, and many practitioners still rely on the traditional measures of brand indicators. The goal of this research is to present the limitations of traditional definition and measurement of brand and brand image, and propose a more direct and adequate measure that reflects the nature of a connected world. Inspired by the proverb, "A man is known by the company he keeps," the proposed measurement offers insight to the position of brand (or brand image) through co-purchased product networks. This paper suggests a framework of network analysis that clusters brands of cosmetics by the frequency of other products purchased together. This is done by analyzing product networks of a brand extracted from actual purchase data on Amazon.com. This is a more direct approach, compared to past measures where consumers' intention or cognitive aspects are examined through survey. The practical implication is that our research attempts to close the gap between brand indicators and actual purchase behavior. From a theoretical standpoint, this paper extends the traditional conceptualization of brand image to a network perspective that reflects the nature of a digitally connected society.

Diurnal Changes of Leaf Water Potential in Cuttings (삽수(挿穗)의 Leaf Water Potential의 변화(變化))

  • Hong, Sung Cheon
    • Journal of Korean Society of Forest Science
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    • v.38 no.1
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    • pp.27-32
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    • 1978
  • The diurnal pattern of leaf water potential in cuttings by Dye Method was as follows: 1. Diurnal pattern of leaf water potential (${\psi}_l$) in Viburnum Awabuki K. Koch and Daphne odora Thunb. was shown the pattern of the curves without mutual relation with soil classes when soil water potential (${\psi}_s$) was 0 bar. When ${\psi}_s$ was above -0.01 bar, the cuttings in the loamy sand (L.S.) was shown by the maximum values than that in sandy clay (S.C.) by about -1 bar gap (Fig. 1). 2. The diurnal changes of ${\psi}_l$ was shown the most high from two to eight O'clock in the morning, the maximum value was -3 bars when ${\psi}_s$ was above -0.01 to -0.02 bar, and was -4 bars below -0.03 bar. The diurnal the lowest values of ${\psi}_l$ showed -20 to -22 bars from one to two O'clock in the afternoon. In the fifteenth day after cutting V.A., the staying time in the diurnal maximum values of ${\psi}_l$ is about half in comparison with it in the fifth day. The curves of recovery of water stress (Fig. 1), the former reached to the diurnal maximum values -1 to -2 bars lately every hours comparing with it of the latter. The general diurnal pattern of ${\psi}_l$ was most clearly related to change with air temperature and the relative humitidy. 3. Comparing the treatment block by IAA 50 ppm with controlled block in fifteenth day after V.A. cuttings, in case of treatment reached to maximum values -2 to -3 bars lately as shown Fig. 2., and also staying times was only half in comparison with controlled block. 4. The cuttings 4 leafs was much rootings than 2 leafs in V.A. (Table. 1), and the former reached maximum value -2 to -3 bars lately every hours comparing with the latter. 5. In case of Buxus microphylla var. Koreana as shown Fig. 3., comparing the pattern curves of in the cuttings 8 leafs with 4 leafs, the former reached to maximum values -2 to -3 bars lately in comparison with the latter, but reffering to the amount of rooting (Table. 2), the former is less than the latter.

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A Numerical and Experimental Study for Fry-drying of Various Sludge (슬러지 유중 건조에 대한 전산 해석 및 실험적 연구)

  • Shin, Mi-Soo;Kim, Hey-Suk;Kim, Byeong-Gap;Hwang, Min-Jeong;Jang, Dong-Soon;Ohm, Tae-In
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.4
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    • pp.341-348
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    • 2010
  • The basic principle of fry drying process of sludge lies in the rapid pressure change of sludge material caused by the change of temperature between oil and moisture due to the difference of specific heat. Therefore, the rapid increase of pressure in drying sludge induces the efficient moisture escape through sludge pores toward heating oil media. The object of this study is to carry out a systematic investigation of the influence of various parameters associated with the sludge fry drying processes on the drying efficiency. To this end, a series of parametric experimental investigation has been made together with the numerical calculation in order to obtain typical drying curves as function of important parameters such as drying temperature, sludge diameter, oil type and sludge type. In the aspect of frying temperature, especially it is found that the operation higher than $140^{\circ}C$ was favorable in drying efficiency regardless of type of waste oil employed in this study. The same result was also noted consistently in the investigation of numerical calculation, that is, in that the sludge particle drying was efficiently made over $140^{\circ}C$ irrespective of the change of particle diameter. As expected, in general, the decrease of diameter in sludge was found efficient both experiment and numerical calculation in drying due to the increased surface area per unit volume. In the investigation of oil type and property, the effect of the viscosity of waste oil was found to be more influential in drying performance. In particular, when the oil with high viscosity, a visible time delay was noticed in moisture evaporation especially in the early stage of drying. However, the effect of high viscosity decreased significantly over the temperature of $140^{\circ}C$. There was no visible difference observed in the study of sludge type but the sewage sludge with a slightly better efficiency. The numerical study is considered to be a quite useful tool to assist in experiment with more detailed empirical modeling as further work.

Development of a High Heat Load Test Facility KoHLT-1 for a Testing of Nuclear Fusion Reactor Components (핵융합로부품 시험을 위한 고열부하 시험시설 KoHLT-1 구축)

  • Bae, Young-Dug;Kim, Suk-Kwon;Lee, Dong-Won;Shin, Hee-Yun;Hong, Bong-Guen
    • Journal of the Korean Vacuum Society
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    • v.18 no.4
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    • pp.318-330
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    • 2009
  • A high heat flux test facility using a graphite heating panel was constructed and is presently in operation at Korea Atomic Energy Research Institute, which is called KoHLT-1. Its major purpose is to carry out a thermal cycle test to verify the integrity of a HIP (hot isostatic pressing) bonded Be mockups which were fabricated for developing HIP joining technology to bond different metals, i.e., Be-to-CuCrZr and CuCrZr-to-SS316L, for the ITER (International Thermonuclear Experimental Reactor) first wall. The KoHLT-1 consists of a graphite heating panel, a box-type test chamber with water-cooling jackets, an electrical DC power supply, a water-cooling system, an evacuation system, an He gas system, and some diagnostics, which are equipped in an authorized laboratory with a special ventilation system for the Be treatment. The graphite heater is placed between two mockups, and the gap distance between the heater and the mockup is adjusted to $2{\sim}3\;mm$. We designed and fabricated several graphite heating panels to have various heating areas depending on the tested mockups, and to have the electrical resistances of $0.2{\sim}0.5$ ohms during high temperature operation. The heater is connected to an electrical DC power supply of 100 V/400 A. The heat flux is easily controlled by the pre-programmed control system which consists of a personal computer and a multi function module. The heat fluxes on the two mockups are deduced from the flow rate and the coolant inlet/out temperatures by a calorimetric method. We have carried out the thermal cycle tests of various Be mockups, and the reliability of the KoHLT-1 for long time operation at a high heat flux was verified, and its broad applicability is promising.

Effects of Salt and Soysauce Condiment on Lipid Oxidation in Broiled Mackerel (Scomber japonicus) (소금과 간장 양념이 고등어 구이의 지질산화 안정성에 미치는 영향)

  • Ryu, Seung-Hee;Lee, Young-Soon;Moon, Gap-Soon
    • Korean Journal of Food Science and Technology
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    • v.34 no.6
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    • pp.1030-1035
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    • 2002
  • Despite health benefits derived from fish oil, polyunsaturated fatty acids (PUFAs) contained in fish oil are susceptible to lipid oxidation. To determine the optimum condition for maintaining good quality cooked fish during storage, mackerels were broiled with salt or soysauce condiments, and the lipid oxidation during 12 days of storage at refrigerated condition was measured. Peroxide value of broiled mackerel group with salt significantly increased after immediate cooking and maintained higher value throughout the storage period compare to the soysauce-added group, but showed similar value to the control group. Conjugated diene content in the soysauce-group was lower than the control and salt-added groups. Malondialdehyde content of broiled mackerel increased twofold and showed similar values in soysauce-added and the control groups during storage, whereas increased in the salt-added group significantly. Fatty acid compositions of the three mackerel groups changed after cooking, whereas that of the control group was almost stable during storage. In comparison with raw mackerel, the ratio of PUFA and saturated fatty acids decreased significantly, and the content of n-3 family fatty acid decreased from 25.53 to 20.63% in salted broiled mackerel. Soysauce group showed no reduction of PUFA with increasing storage time and showed the highest ratio of n-3/n-6 among the three groups at 10 days storage. Results reveal soysauce condiment protects against lipid peroxidation of broiled mackerel. Maillard reaction products (MRPs) found in soysauce might be responsible for the inhibitory effect and is a good condiment for extending storage life of cooked fish containing high amount of PUFA.

A Study on Perception Change in Bicycle users' Outdoor Activity by Particulate Matter: Based on the Social Network Analysis (미세먼지로 인한 자전거 이용객의 야외활동 인식변화에 관한 연구: 사회네트워크분석을 중심으로)

  • Kim, Bomi;Lee, Dong Kun
    • Journal of Environmental Impact Assessment
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    • v.28 no.5
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    • pp.440-456
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    • 2019
  • The controversy of the risk perception related to particulate matters becomes significant. Therefore, in order to understand the nature of the particulate matters, we gathered articles and comments in on-line community related to bicycling which is affected by exposure of the particulate matters. As a result, firstly, the government - led particulate matter policy was strengthened and segmented every period, butthe risk perception related to particulate matters in the bicycle community has become active and serious. Second, as a result of analyzing the perception change of outdoor activities related to particulate matters, bicycle users in community showed a tendency of outdoor activity depending on the degree of particulate matters ratherthan the weather. In addition, the level of the risk perception related to particulate matters has been moved from fears of serious threat in daily life and health, combined with the disregard of domestic particulate matter levels or mask performance. Ultimately, these risk perception related to particulate matters have led some of the bicycling that were mainly enjoyed outdoors to the indoor space. However, in comparison with outdoor bicycling enjoyed by various factors such as scenery, people, and weather, the monotonous indoor bicycling was converted into another type of indoor exercise such as fitness and yoga. In summary, it was derived from mistrust of excessive information or policy provided by the government or local governments. It is considered that environmental policy should be implemented after discussion of risk communication that can reduce the gap between public anxiety and concern so as to cope with the risk perception related to particulate matters. Therefore,this study should be provided as an academic basis for the effective communication direction when decision makers establish the policy related to particulate matters.

Recent research activities on hybrid rocket in Japan

  • Harunori, Nagata
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.04a
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    • pp.1-2
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    • 2011
  • Hybrid rockets have lately attracted attention as a strong candidate of small, low cost, safe and reliable launch vehicles. A significant topic is that the first commercially sponsored space ship, SpaceShipOne vehicle chose a hybrid rocket. The main factors for the choice were safety of operation, system cost, quick turnaround, and thrust termination. In Japan, five universities including Hokkaido University and three private companies organized "Hybrid Rocket Research Group" from 1998 to 2002. Their main purpose was to downsize the cost and scale of rocket experiments. In 2002, UNISEC (University Space Engineering Consortium) and HASTIC (Hokkaido Aerospace Science and Technology Incubation Center) took over the educational and R&D rocket activities respectively and the research group dissolved. In 2008, JAXA/ISAS and eleven universities formed "Hybrid Rocket Research Working Group" as a subcommittee of the Steering Committee for Space Engineering in ISAS. Their goal is to demonstrate technical feasibility of lowcost and high frequency launches of nano/micro satellites into sun-synchronous orbits. Hybrid rockets use a combination of solid and liquid propellants. Usually the fuel is in a solid phase. A serious problem of hybrid rockets is the low regression rate of the solid fuel. In single port hybrids the low regression rate below 1 mm/s causes large L/D exceeding a hundred and small fuel loading ratio falling below 0.3. Multi-port hybrids are a typical solution to solve this problem. However, this solution is not the mainstream in Japan. Another approach is to use high regression rate fuels. For example, a fuel regression rate of 4 mm/s decreases L/D to around 10 and increases the loading ratio to around 0.75. Liquefying fuels such as paraffins are strong candidates for high regression fuels and subject of active research in Japan too. Nakagawa et al. in Tokai University employed EVA (Ethylene Vinyl Acetate) to modify viscosity of paraffin based fuels and investigated the effect of viscosity on regression rates. Wada et al. in Akita University employed LTP (Low melting ThermoPlastic) as another candidate of liquefying fuels and demonstrated high regression rates comparable to paraffin fuels. Hori et al. in JAXA/ISAS employed glycidylazide-poly(ethylene glycol) (GAP-PEG) copolymers as high regression rate fuels and modified the combustion characteristics by changing the PEG mixing ratio. Regression rate improvement by changing internal ballistics is another stream of research. The author proposed a new fuel configuration named "CAMUI" in 1998. CAMUI comes from an abbreviation of "cascaded multistage impinging-jet" meaning the distinctive flow field. A CAMUI type fuel grain consists of several cylindrical fuel blocks with two ports in axial direction. The port alignment shifts 90 degrees with each other to make jets out of ports impinge on the upstream end face of the downstream fuel block, resulting in intense heat transfer to the fuel. Yuasa et al. in Tokyo Metropolitan University employed swirling injection method and improved regression rates more than three times higher. However, regression rate distribution along the axis is not uniform due to the decay of the swirl strength. Aso et al. in Kyushu University employed multi-swirl injection to solve this problem. Combinations of swirling injection and paraffin based fuel have been tried and some results show very high regression rates exceeding ten times of conventional one. High fuel regression rates by new fuel, new internal ballistics, or combination of them require faster fuel-oxidizer mixing to maintain combustion efficiency. Nakagawa et al. succeeded to improve combustion efficiency of a paraffin-based fuel from 77% to 96% by a baffle plate. Another effective approach some researchers are trying is to use an aft-chamber to increase residence time. Better understanding of the new flow fields is necessary to reveal basic mechanisms of regression enhancement. Yuasa et al. visualized the combustion field in a swirling injection type motor. Nakagawa et al. observed boundary layer combustion of wax-based fuels. To understand detailed flow structures in swirling flow type hybrids, Sawada et al. (Tohoku Univ.), Teramoto et al. (Univ. of Tokyo), Shimada et al. (ISAS), and Tsuboi et al. (Kyushu Inst. Tech.) are trying to simulate the flow field numerically. Main challenges are turbulent reaction, stiffness due to low Mach number flow, fuel regression model, and other non-steady phenomena. Oshima et al. in Hokkaido University simulated CAMUI type flow fields and discussed correspondence relation between regression distribution of a burning surface and the vortex structure over the surface.

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Comparative Assessment of Linear Regression and Machine Learning for Analyzing the Spatial Distribution of Ground-level NO2 Concentrations: A Case Study for Seoul, Korea (서울 지역 지상 NO2 농도 공간 분포 분석을 위한 회귀 모델 및 기계학습 기법 비교)

  • Kang, Eunjin;Yoo, Cheolhee;Shin, Yeji;Cho, Dongjin;Im, Jungho
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1739-1756
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    • 2021
  • Atmospheric nitrogen dioxide (NO2) is mainly caused by anthropogenic emissions. It contributes to the formation of secondary pollutants and ozone through chemical reactions, and adversely affects human health. Although ground stations to monitor NO2 concentrations in real time are operated in Korea, they have a limitation that it is difficult to analyze the spatial distribution of NO2 concentrations, especially over the areas with no stations. Therefore, this study conducted a comparative experiment of spatial interpolation of NO2 concentrations based on two linear-regression methods(i.e., multi linear regression (MLR), and regression kriging (RK)), and two machine learning approaches (i.e., random forest (RF), and support vector regression (SVR)) for the year of 2020. Four approaches were compared using leave-one-out-cross validation (LOOCV). The daily LOOCV results showed that MLR, RK, and SVR produced the average daily index of agreement (IOA) of 0.57, which was higher than that of RF (0.50). The average daily normalized root mean square error of RK was 0.9483%, which was slightly lower than those of the other models. MLR, RK and SVR showed similar seasonal distribution patterns, and the dynamic range of the resultant NO2 concentrations from these three models was similar while that from RF was relatively small. The multivariate linear regression approaches are expected to be a promising method for spatial interpolation of ground-level NO2 concentrations and other parameters in urban areas.

Psychology of the self-nature in platform sutra-focused on dynamics in essential and inclusive self-nature (『단경』에 나타난 자성의 심리학 - 본래적 자성과 포괄적 자성의 역동성을 중심으로)

  • Youn, Hee-jo
    • Journal of Korean Philosophical Society
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    • v.146
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    • pp.137-162
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    • 2018
  • Zen Psychology refers to the psychology of Zen Buddhism as a field of Buddhist psychology. This paper examines the psychology of human beings, focusing on the "Platform Sutra" written by Huineng, the founder of Patriarchal Zen, and the southern Zen school. According to the classification of Buddhist psychology, Zen psychology is divided into theory of Zen mind, theory of Zend mind function, and Zen psychotherapy. In theory of Zen mind, Huineng explains the mind based on self-nature, and explains the theory of dharma, theory of humanity, theory of dependent origination, and worldview though self-nature. Every human mind has its own original character of self-nature. When one's own mind with self-nature is revealed, it is the basic mind. When it is covered, it is the mind of common people. Self-nature is characterized by dharma construction, incompetence, non-naming, cleanliness, equality, and self-Buddhahood. In the theory of dharma, dharma is non-dual and is equal. The theory of humanity is divided into two groups according to the sharpness and dullness or capacity of the human being. From theory of dependent origination, you can see the mobility of cover and revealment, enlightment and delusion, sacred and common. In the worldview, the world and phenomena are the functions of self-nature and one's own mind. The theory of Zen mind function deals with wisdom and defilement of common people. The function of wisdom is to know the whole and one at the same time, and is intangible. Defilement of common people is an inner common people that cover the functions of wisdom. In Zen psychotherapy, in order to eliminate the gap between human and dharma, seeing into self-nature is suggested and the goal. In teleology, the goal is to reveal and see the self-nature covered by defilements. As a methodology from cover to revealment, Huineng interprets the traditional methodology as a new interpretation from the viewpoint of the mind, and presents Sammu as its own methodology. Based on the absence of attachment, Huineng proposed a methodology of No-abiding, No-thought and No-form, to gather mind on reality and treat all things equally. Based on this, Huineng proposed a new methodology for dealing with karma through repentance and vows, and a methodology for edification. In view of the Four Noble Truth, it is the phenomenon that self-nature is covered, the cause of defilement and the mind, the aim of seeing the self-nature which is covered, and the way of revealing the covered self-nature is presented. In this sense, the Zen Psychology of Platform Sutra is psychology of self-nature.

Comparison of Educators and Students' Perception of Evaluation Criteria for Admission to Career and Technical High Schools: A Case Study (특성화고등학교 미래인재전형의 평가기준에 대한 교사와 학생의 인식비교 : 서울시교육청 특성화고 사례를 중심으로)

  • Cho, Sung Ran;Lee, Hwa-Yeong;Han, jiyoon;Ye, Cheol-Hae;Shin, Changho
    • (The)Korea Educational Review
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    • v.24 no.1
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    • pp.227-254
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    • 2018
  • This study examines differences in perception between applicants and admissions committee members regarding evaluation criteria for admission to career and technical high schools in Seoul. This investigation, based on "The survey on policy for career and technical high school admissions," seeks to explore and consider the various criteria for selecting and evaluating students. The target populations of the survey were the educators in charge of admission and freshmen in Seoul career and technical high schools. We report three major findings, with the first pertaining to the existing criteria and policies for admission to career and technical high schools. While educators agreed with the intent and reasoning behind the school's competitive spots, they were overall dissatisfied with the selection method and the lack of a requirement for academic transcripts. Matriculated students, in comparison, expressed greater satisfaction with the existing criteria for admission. Secondly, when assessing the importance of various evaluation components in an application, educators viewed the interview and attendance record as the most valuable components of the application, followed by future plans, personal statement, volunteer work, and portfolio, in order of decreasing importance. Students ranked attendance record, interview, personal statement, portfolio, future plans, and volunteer work as most to least important components of their application. Thus, students regarded the personal statement and portfolios as being of higher priority than did the educators. The last major finding pertained to students' rationale for applying and educators' selection criteria. At the time of application, students focused on aptitude and job prospects after graduation, while educators valued personality and competence. In summary, the applicants' viewpoints and actions aligned much more closely with the mission of the Seoul Metropolitan Office of Education than did those of the educators in charge of admission. Thus, in order to establish a consensus between the policy and mission of career and technical high schools, each career and technical high school should clarify the exact criteria for their ideal candidate. There is also a need to bridge the gap in perception between the applicants and educators regarding selection strategy, to establish a harmonized evaluation criteria. These goals are necessary to attract and recruit talented, bright individuals who will meet the demands of today's society.