• Journal of Mechanical Science and Technology
• /
• v.15 no.2
• /
• pp.248-258
• /
• 2001

The main mode of heat transfer of combustion gases at high temperature is thermal radiation of the participating gases, which are mainly carbon dioxide and water vapor. Therefore, the information of the emissivities of carbon dioxide and water vapor would be very important in the thermal performance analysis of a furnace. In this study, an exponential model for the emissivities of carbon dioxide and water vapor is derived as a function of the product of the partial pressure and characteristic length and a polynomial of reciprocal of temperature. Error analysis of the calculated values from the present model is performed for the temperature ranges of 555.6∼2777.8K and the partial-pressure-length product ranges of 0.09144∼609.6 cm-atm. For carbon dioxide, the difference between the values from the present model and the Hottels chart is less than 2.5% using a polynomial in 1/T of degree of 4. For water vapor, the model can predict the emissivity within 2.5% difference using a polynomial in 1/T of degree of 3.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.53
• /
• pp.265-288
• /
• 2012

Trade in service, which deals with intangible product, is distinguished from trade of goods for tangible product. The current multilateral service trade is based on GATS which includes MFN, securing the predictability as well as transparency of related service rules, specific commitment basis market access national treatment. Recently the WTO service disputes are increasing according to the frequent filing complaints against the regulation of service trade in China. The rules of GATS are not as strict as those of GATT. The commitment schedules, which were materialized between members, gets binding effect through the obligatory provisions of GATS. The GATS is inseparable relation with the Appendix of finance, of telecommunication, and of air transport, with the schedules of commitment of member states, and with the reference paper to the 4th protocol. GATS article XIV which is the general exception of GATS has a similar structure of GATT article XX. Based on the possibility of filing to the WTO, there is a need to examine whether the whole rules, regulation, and policy international trade in service of Korea perfectly macthed with the GATS. Korea with poor resources should take up the more positive attitude for the opening of international service market. According to the reciprocal aspects of concession, if Korea doesn't open a service market, the other WTO member country wouldn't allow Korea to access the their market as well as national treatment.

• East Asian mathematical journal
• /
• v.32 no.4
• /
• pp.565-587
• /
• 2016

The purpose of this study was to analyze the understanding of the meaning of fraction division and fraction division algorithm of elementary mathematical gifted students through the process of problem posing and solving activities. For this goal, students were asked to pose more than two real-world problems with respect to the fraction division of ${\frac{3}{4}}{\div}{\frac{2}{3}}$, and to explain the validity of the operation ${\frac{3}{4}}{\div}{\frac{2}{3}}={\frac{3}{4}}{\times}{\frac{3}{2}}$ in the process of solving the posed problems. As the results, although the gifted students posed more word problems in the 'inverse of multiplication' and 'inverse of a cartesian product' situations compared to the general students and pre-service elementary teachers in the previous researches, most of them also preferred to understanding the meaning of fractional division in the 'measurement division' situation. Handling the fractional division by converting it into the division of natural numbers through reduction to a common denominator in the 'measurement division', they showed the poor understanding of the meaning of multiplication by the reciprocal of divisor in the fraction division algorithm. So we suggest following: First, instruction on fraction division based on various problem situations is necessary. Second, eliciting fractional division algorithm in partitive division situation is strongly recommended for helping students understand the meaning of the reciprocal of divisor. Third, it is necessary to incorporate real-world problem posing tasks into elementary mathematics classroom for fostering mathematical creativity as well as problem solving ability.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.7
• /
• pp.1221-1225
• /
• 2007

A ${\beta}$-ionone-resistant mutant strain isolated from the red yeast Xanthophyllomyces dendrorhous KCTC 7704 was used for batch and continuous fermentation kinetic studies with glucose media in a 2.5-1 jar fermentor at $22^{\circ}C$ and pH 4.5. The kinetic pattern of growth and carotenoid concentration in the batch fermentations exhibited a so-called mixed-growth-associated product formation, possibly due to the fact that the content of intracellular carotenoids depends on the degree of physical maturation toward adulthood. To determine the maximum specific growth rate constant (${\mu}_m$) and Monod constant ($K_s$) for the mutant, glucose-limited continuous culture studies were performed at different dilution rates within a range of $0.02-0.10\;h^{-1}$. A reciprocal plot of the steady-state data (viz., reciprocal of glucose concentration versus residence time) obtained from continuous culture experiments was used to estimate a ${\mu}_m$ of $0.15\;h^{-1}$ and $k_s$ of 1.19 g/l. The carotenoid content related to the residence time appeared to assume a typical form of saturation kinetics. The maximum carotenoid content ($X_m$) for the mutant was estimated to be $1.04\;{\mu}g/mg$ dry cell weight, and the Lee constant ($k_m$), which was tentatively defined in this work, was found to be 3.0 h.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.7 no.1
• /
• pp.125-134
• /
• 2012

The concerns for entrepreneurship education has increased significantly in decades. Government asking to university to teach the entrepreneurship on the undergraduate and graduate level. Existing graduate-level entrepreneurship program is not enough for the reciprocal relationship among the subjects. This study review the university's entrepreneurship program in the domestic and abroad. We suggest the process and algorithm based education program which is The Technology Entrepreneurship and Commercialization.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.1513-1518
• /
• 1996

A force reflecting hand controller can be used to provide more realistic information to the operator of a teleoperation system such as kinesthetic feedback from a slave robot. In this paper, a new design concept of a force reflecting 6-DOF hand controller utilizing the kinematic structure of a Stewart Platform is presented. Based on the optimal design technique of a Stewart Platform, a force reflecting hand controller has been designed and constructed to verify the technical feasibility of proposed design concept. In order to provide an operator with kinesthetic feedback information, a force mapping algorithm based on a reciprocal product of screws has been introduced. Finally, the technical feasibility of the design concept has been demonstrated through some of experimental results of the device under virtual environment on a real-time graphic system.

• Journal of Korean Society for Quality Management
• /
• v.34 no.3
• /
• pp.19-30
• /
• 2006

For highly reliable products, it is difficult to assess the lifetime of the products with traditional life tests. Accordingly, a recent approach is to observe the performance degradation of product during the test rather than regular failure time. This study compares performances of three methods(i.e. the approximation, analytical and numerical methods) to estimate the parameters and quantiles of the lifetime when the time-to-failure distribution follows Weibull and lognormal distributions under a random coefficient degradation rate model. Numerical experiments are also conducted to investigate the effects of model error such as measurements in a random coefficient model.

• Journal of Applied Reliability
• /
• v.2 no.2
• /
• pp.63-83
• /
• 2002

Degradation data can provide more reliability information than traditional failure-time data, especially products with few or no failures. This paper is concerned with a method of estimating lifetime distribution from field data with supplementary information on degradation data and covariates. When a distribution of degradation rate obtained by follow-up study for a portion of products that survive after-warranty follows a reciprocal-Weibull or lognormal distribution. A time-to-failure distribution of the product follows Weibull or lognormal distribution, respectively. A method of estimating lifetime parameters for this kind of data and their asymptotic properties are studied. Effects of after-warranty report probability, follow-up rate, and proportion of degradation data on pseudo maximum likelihood estimators of these parameters are investigated.

• Journal of KSNVE
• /
• v.9 no.5
• /
• pp.984-990
• /
• 1999

This paper presents the geometrical methodology to decouple the vibration modes of an elastically supported single rigid body in three-dimensional space. It is shown that the vibration modes can be decoupled by placing the center of elasticity at suitable locations and thereby yielding the plane(s) of symmetry for the given stiffness matrix. The developed methodology has been applied to the actuator supported by the 4-wire suspensions in optical discs, which has one plane of symmetry. For this numerical example, the axes of vibrations have been computed and illustrated with the natural frequencies. The forced response at the objective lens is represented and its geometrical interpretation has been explained as the mutual moment between the axis of vibration and the applied wrench times the line coordinates of the axis of vibration.

• Asian Journal of Innovation and Policy
• /
• v.12 no.3
• /
• pp.383-400
• /
• 2023

This research focuses on examining the mobilization of Public Procurement for Innovation (PPI) in South Korea as a case study in technology innovation. By using the lens of policy mobility and qualitative research methodologies, it emphasizes the circulation of PPI is an outcome of an assemblage of multiple actors who are responsible for the introduction of PPI. The Public Procurement Service in South Korea has actively sought to understand and adopt the concept of PPI from developed countries. This initiative has been localized under the umbrella of 'innovative technology and product.' Throughout the mobilization, a cadre of technocrats, the Innovation Procurement Competence Center plays a pivotal role, and particularly encourages Small and Medium Enterprises to bolster their export capabilities, resulting in a reciprocal circulation of policies and programs from South Korea to foreign countries as well as within intra-urban area. Consequently, the above findings, revealing the nuanced evolution of policy mobility in local contexts, hold practical significance as they provide valuable insights and lessons for urban studies.