• Journal of ILASS-Korea
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• v.27 no.1
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• pp.1-10
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• 2022

In this study, an experimental investigation on the effects of the pressure ratio on the wall-impingement spray characteristics of nitrogen gas using a compressed natural gas (CNG) injector was conducted. The transient development of the impingement spray was recorded by a high speed camera with Z-type Schlieren visualization method. The spray behavior under various pressure ratio conditions were analyzed. The experimental results showed that the pressure ratio has positive effect on the development of spray wall-impingement. The effects of the above factor were evaluated in a constant volume chamber at atmospheric conditions. The data from test showed that, with the increase of the pressure ratio, the spray tip penetration (STP) quickly increases before the impingement and gradually increases after the impingement. Additionally, the spray velocity first increases and then sharply decreases on regardless of the injection pressure level. As the spray spreading angle increases, spray area and volume increases rapidly with the increase in STP at the beginning of injection, and finally entered a stable range, has a great correlation with the increase of pressure ratios.

• The Korean Journal of Pesticide Science
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• v.13 no.2
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• pp.111-116
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• 2009

Juvenile hormone (JH) is an insect hormone mediating immature metamorphosis and adult reproduction. It also mediates immune responses to suppress hemocyte behavior, which is, however, activated by ecdysteroid. This study investigated an effect of a commercial pyriproxyfen (a JH agonist) formulation on a cellular immune response of the diamondback moth, Plutella xylostella, and analysed its mixture with Bacillus thuringiensis (Bt) in insecticidal potency. The commercial pyriproxyfen formulation significantly suppressed hemocyte-spreading behavior at low doses as did in pyriproxyfen technical grade. When the commercial pyriproxyfen formulation was mixed with Bt, Bt toxicity was significantly increased against P. xylostella larvae in laboratory. The mixture effect was then confirmed in field cultivating cabbage infested with P. xylostella larvae. The mixture showed a significantly enhanced mortality and reduced effective lethal time, compared to only Bt treatment.

• Fire Science and Engineering
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• v.15 no.2
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• pp.59-79
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• 2001

The paper proposes alternatives for fire safety in architectural planning through heat-smoke distribution related to openings so that we decrease casualty and property loss by fire and lay a great emphasis on building high-rise apartments with consideration of fire safety in Korea. An analysis program(HFA-Heat Fluid Analysis) is built to perform simultaneously numerical analysis and experimental analysis on rooms, units and buildings. In consequence, on the first, fire prevention methods are required to be set up related to openings for design rooms since the flow of heat and smoke is influenced by the type of openings in high-rise apartments. Second, the numerical analysis showed that different planning types cause to show differences in the spreading time of heat and smoke to design the units of high-rise apartments. On the third, each unit building showed different fire behavior depending on openings by numerical analysis and small scaled experiment on heat and smoke flow.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.179-188
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• 2010

The concern of Software Product Line(SPL) engineering is spreading widely because the program or product developers are able to satisfy the customer's demands quickly and give a way to handle maintenance efficiently. SPL is a reuse paradigm that reuse common parts and adopts variable parts optionally to form a differentiated product by analyzing domains. Purposes of this paper are to design an architecture which has a dynamic reconfiguration function and to develop basic components which are the basic unit of reconfiguration to raise the reuse level of the guided weapon system using the SPL. Initially we design an architecture and define basic components for developing a dynamic reconfigurable components based on SPL. Then we develop the composer for physical components and behavior components referenced by behavior models of OneSAF.

• The Journal of the Convergence on Culture Technology
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• v.10 no.2
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• pp.11-16
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• 2024

Recently, the health-pleasure trend, which means enjoying health care through exercise or diet and certifying it on SNS is spreading to the MZ generation. This study examined the effect of personality traits on SNS upload behavior and subjective well-being related to health care. As a result, 1) parallel comparison and narcissism had a positive effect on the SNS upload attitude and intention, and the downward comparison had a negative effect on both SNS upload variable. Self-esteem had a positive effect only on the attitude of uploading SNS. Next, 2) self-esteem had a positive effect on both subjective well-being, while narcissism had a negative effect on stress, and parallel comparisons had a positive effect on life satisfaction. In other words, it was confirmed that comparisons with similar people had a positive effect on SNS upload behavior and their subjective well-being, while health care for self-show or recognition of others had a negative effect on their subjective well-being. The results of this study should be actively reflected not only for the marketing market but also for a media and cultural environment in which the MZ generation can lead a healthy life.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.4
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• pp.303-315
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• 2020

The development of ICT is spreading various contents to enhance health care and management efficiency through convergence between mobile and healthcare, but it indicates consumer acceptance and imbalance of mobile healthcare, and there is a lack of empirical research on functions and acceptability required according to consumer behavior and characteristics. This study sought to understand whether users were aware of and how to address the risks associated with smartphone use, and to conduct research on the acceptability and function and price of healthcare applications. For the purpose of the study, the data prepared in depth 1:1 survey for those who participated in and attended the 'BIO 2018 in Boston' exhibition was used for the actual analysis. The collected sample data included frequency analysis, technical statistical analysis, speech only correlation, chi square test, one-way analysis, and accuracy test. As a result, the more you realize the wrong attitude, the higher the awareness of risk and willingness to take action to solve problems. Second, it is necessary to increase satisfaction with the functions of healthcare apps, as well as to utilize health care and healthcare apps. Third, focus should be placed on systems or functional implementations centered on user behavior changes. Fourth, it is necessary to develop services that can enhance visual motivation. This study is meaningful in that it identifies a variety of consumer characteristics and provides directions for development of functions, and can be used as a basis for providing efficient healthcare applications in the future.

• Culinary science and hospitality research
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• v.23 no.2
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• pp.104-116
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• 2017

The purpose of this study was to conduct an empirical survey on consumer perception and consumption behavior in relation to local food and eco-friendly food. The survey was conducted using 266 consumers who have heard about or purchased local foods and eco-friendly foods centering on Seoul and Gyeonggi-do, and statistical analysis was carried out using SPSS (Version 23.0) to generate descriptive statistical values such as frequency and percentage and implement a Chi-square test. The results showed that consumers purchased local food in large shopping malls, supermarkets, and local food stores, whereas eco-friendly food were usually bought in large shopping malls, supermarkets, and eco-friendly food specialty stores. For local food, consumers bought fruits the most, followed by vegetables, whereas for eco-friendly food, consumers purchased vegetables the most, followed by fruits. The top reason for purchasing local food was its "fresh and high quality," whereas the top reason for buying eco-friendly food was "safety from pesticides and additives." According to results of the Chi-square test, women, unmarried people and younger people turned out to have more experiences in purchasing local foods and eco-friendly foods compared to men, married people and older people, respectively. Although local and eco-friendly food were completely different concepts, results of the study show that consumers were not able to make a clear distinction between the two. Consumer education, therefore, should involve defining the two types of food and spreading awareness on local and organic food to help them made the right choices when buying food.

• The Journal of Fisheries Business Administration
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• v.18 no.1
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• pp.37-57
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• 1987

This article discussed the characteristics of several Pareto-optimal incentive contracts between owner and labor, more specifically, four situations: reporting output jointly observable by labor ana owner; reporting both output and effort; incorporating other endogenous elements (like capital) that affect the production process and Pareto-optimal fee schedules; and ascertaining the effects of private pre-decision information private- decision information, and per-contact informational asymmetries. Also presented were several extensions of the basic contractual model, and the different components of agency costs associated with labor-owner contractual relations. In a single-period model, the agency problem exists because the uncertainty prevents the owner from using the cash flow to determine unambiguously the labor's action. Holmstrom(1979) suggests that "when the same situation repeats itself over time, the effects of uncertainty tend to be reduced and dystunctional behavior is more accurately revealed, thus alleviating the problem of moral hazard. " Under these conditions, if the labor selects the first-best level of effect in each period, the cash flow will be independent and identically distributed over time. As the number of periods increases, the variance of the labows average output, if he selects the first-best level of effort in each period, gets smaller. Note that for this diversification effect to occur, it is necessary that the owner evaluate the labor's effort over the entire history of his employment, rather than evaluate each period's performance separately. Radner(1980) and Rubinstein and Yaari(1980) consider the extreme case in which there are an infinite number of observations. They show that the owner can eventually detect and systematic shirking on the part of the labor by comparing the labor's average output with what would be expected if the labor had been selecting the first-best level of effort in each period. In a dynamic model with incentive problems we have demonstrated that the labor's second-period compensation will depend on his first-period performance. This allows the owner to diversify away some of the uncertainty surrounding the labor's actions. In addition, this allows the owner to smooth the labor's income over time by spreading the risk of the first-period outcome over both periods. At least some unexplored avenves in this area invite future accounting research: situations where owner has different incompatible objectives and negotiates a contract with labor; circumstances in which owner deals with multiple objectives and negotiates contracts with several labors simultaneously; the value of costly accounting information systems and communication in establishing, Pareto-optimal incentive contracts, and the value and effects of inside information, Thorough theoretical or empirical research on each of these topics not only would increase our knowledge about the role and significance of accounting information but could also provide explanations of the inherent differences among various organizations and in their economic behavior. behavior.

• Journal of Information Management
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• v.43 no.3
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• pp.61-78
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• 2012

Internet is widely spreading in everyday life and it makes easy to find and share information on the Internet. Many of Internet users are copying and distributing copyrighted materials freely on the Internet without recognizing that it is unethical and illegal behavior. The rate of Internet piracy is constantly increasing even though the regulation and punishment for piracy behavior are to be strict. However, there is a lack of study about the relationship between the punishment and education for intenet piracy on users' attitude and intention toward piracy on the Internet. The purpose of this study is therefore to find out the effect of the level of punishment for internet piracy on users' attitude and intention. This study also examines the moderating effect of piracy education on the relationship between punishment and piracy intention. The study shows that the punishment is directly associated with the attitude but not associated with the piracy intention. The piracy education has a significant effect on the relationship between punishment and intention. The result of this study could bring up the issue of intellectual property protection on the Intenet and suggest an importance of piracy education to educators, managers and internet users.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.3
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• pp.123-129
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• 2018

Ink-jet printing technology with ceramic ink of the four digital primary colors (cyan, magenta, yellow, and black; CMYK) can provide stable coloration even in the high-temperature firing process. Ceramic ink-jet printing can be widely applied in construction and ceramic industries due to the advantages of accurate and fast printing process of digital images for various products. Generally, organic solvent with proper viscosity and surface tension has been used in digital ink-jet printing process. However, the needs of ceramic ink without VOCs emission is increasing. In the present study, eco-friendly ceramic ink was synthesized by combining alumino boro-silicate glass frit and $CoAl_2O_4$ inorganic pigment based on an aqueous solvent that does not generate VOCs. The rheological properties and dispersion stability of aqueous ceramic ink were optimized. Jetting behavior and printing characteristics of the ceramic ink were also investigated in detail. As a result, the formulated aqueous ceramic complex ink showed a suitable jetting behavior without satellite drop by adjusting viscosity and surface tension. The ceramic ink can be printed on glass substrate with minimized spreading phenomena duo to high contact angle.