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The term structure of KTB (Korea Treasury Bond) is empirically implemented and forecasted by the extended 2-factor CIR model. Pearson and Sun model. MLE is applied to estimate parameters. Using KTB prices forecasted by the model, strategies of trading and hedge between KTB, KTF (Korea Treasury Futures) are established. In this article we can see that Pearson and Sun model appropriately explains the term structure of KTB but does not fit forecasting KTB prices. However, the model well forecasts the direction of interest rate moving up or down. Through such a forecast‘ profit via trading KTB and KTF can be realized.

Places Korean chaebols (i.e. family‐owned conglomerates) in the context of organizational theory, characterizes them as leveraged controlling minority structure firms and discusses the behavioural consequences of this. Examines their long term performance in terms of diversification/changinb business environment, aggressive investment drive and the effects of management by one man. Considers the necessary conditions for efficient corporate governance and relates them to various Korean reforms, e.g. to protect minority shareholders. Summarizes the findings of the study and briefly considers their implications.

The purpose of this paper is to investigate the impact of different dimensions of corporate governance practices such as board characteristics, ownership structure, corporate disclosure and CEO education on the operating performance of Russian banks before, during and after financial crises. Based on the findings, it proposes some policy measures for improved governance practices to protect banks from future financial crisis or economic downturns.

The study comprises data from the largest publicly traded Russian banks listed on the Russian Stock Exchange RST for the period. Operating performance data were collected from financial statements, while corporate governance mechanisms were collected from annual reports available on the banks’ websites. Because panel data were used, the panel regression model was used to control unobserved time-constant heterogeneity.

The findings revealed a positive impact of corporate governance on bank performance before and after the financial crisis. The financial crisis enforced Russian banks to improve their corporate governance practices, resulting in better operating performance after the crisis. Surprisingly, the results for the during-crisis period show that better governance did not yield higher operating performance in Russian banks.

This is one of the first studies to provide empirical results regarding the relationship between corporate governance practices and bank performance in Russia across different financial crisis periods. The findings revealed the uniqueness of corporate governance scenarios of Russia which could provide important guidelines for other transition economies and emerging markets.

The purpose of this paper is to carry out an in-depth analysis of heat dissipation performance by natural convection phenomenon inside light-emitting diode (LED) lamps containing hot pin-fins because of its significant industrial applications.

The problem is assimilated to heat transfer inside air-filled rectangular cavity with various governing parameters appraised in ranges interesting engineering application and scientific research. The lattice Boltzmann method is used to predict the dynamic and thermal behaviors. Effects of monitoring parameters such as Rayleigh number Ra (10³-10⁶), fin length (0-0.25) and its position, pin-fins number (1-8), the tilting-angle (0-180°) and cavity aspect ratio Ar (0.25-4) are carried out.

The rising behaviors of the dynamic and thermal structures and heat transfer rate (Nu), the heatlines distribution and the irreversibility rate are appraised. It was found that the flow is constantly two contra-rotating symmetric cells. The heat transfer is almost doubled by increasing Ra. A lack of cooling performance was identified between Ar = 0.5 and 0.75. The inclination 45° is the most appropriate cooling case. At constant Ra, the maximum stream-function and the global entropy generation remain almost unchanged by increasing the pin number from 1 to 8 and the entropy generation is of thermal origin for low Ra, so that the fluid friction irreversibility becomes dominant for Ra larger than 10⁵.

Improvements may include three-dimensional complex geometries, accounting for thermal radiation, high unit power and turbulence modelling. Such factors effects will be conducted in the future.

The cooling performance/heat dissipation in LED lamps is a key manufacturing factors, which determines the lifetime of the electronic components. The best design and installation give the opportunity to increase further the product shelf-life.

Both cooling performance, irreversibility rate and enclosure configuration (aspect ratio and inclination) are taken into account. This cooling scheme will give a superior operating mode of the hot components in an era where energy harvesting, storage and consumption is met with considerable attention in the worldwide.

This research examines the linkage between commitment (organizational and job), motivation (intrinsic and extrinsic), and work outcomes (effort and propensity to leave) using the Korean sample. With its focus on the relative impact of loyalty‐based commitment and incentive‐based motivation on work outcome behavior, this study highlights Confucian culture and expectancy theory. Using survey data, support was found for all the hypotheses except the paths from job involvement to effort. In particular, organizational commitment was found to have the highest influence on effort and propensity to leave, presenting empirical support for the eminence of loyalty as a motivational tool in a collectivistic work culture. Managerial implications and future research are discussed.

The purpose of this paper is to investigate the thermal behaviors of high power LED packages to enhance the thermal performances of low temperature co‐fired ceramic chip on board (LTCC‐COB) package. Thermal analysis demonstrated an improved LTCC‐COB package design that is comparable to a metal lead frame package with low thermal resistance.

The LED device developed in this study is a LTCC package mounted directly on the metal PCB. A numerical simulation was performed to investigate the thermal characteristics of the LED module using the finite volume method, which is embedded in commercial software (Fluent V.6.3). Thermal resistance and temperature measurement validate the simulated results.

The effect of the thickness of the die attach material on the thermal resistance was dominant due to low thermal conductivity, and the junction temperature decreased significantly with slight increases in thermal conductivity, especially when the value was less than 5 W/mK. The results reveal that the thermal resistance of MCPCB is about 49 per cent‐58 per cent of the junction to board thermal resistance. The thermal model results showed good agreement with experimental results.

The developed model overcomes the large thermal resistance of a conventional LTCC package for high power LED module. The extensive results have demonstrated an improved thermal design, optimal dimensions of each component and boundary conditions for high power LTCC‐COB type package.

Field survey studies undertaken in Nigeria, Korea, China and India explored the way inner‐age satisfaction is experienced in those culturally diverse societies. Chronologically 20 to 59 year old respondents’ inner‐age satisfaction was gauged as the average difference between feel, look, do, and interest cognitive (self‐perceived) and desired (ideal) inner‐age dimensions. Analyses of covariance (with chronological age factored out) across the four nations showed Nigeria to differ significantly in terms of inner‐age satisfaction from each Asian population, contrary to the Asian societies where no differences were found across samples (except between Korea and India where inner‐age satisfaction differed at a p .05). High levels of satisfaction with inner‐age (coming about when cognitive and desired ages are equal) commonly transpired: 31.4 per cent of Indian, 36.9 per cent of Nigerian, 44.3 per cent of Chinese, and 44.9 per cent of Korean respondents. Age dissatisfaction in an elder direction (ideal age older than self‐perceived age) was atypical and happened most often among Nigerian (23.4 per cent) and least among Korean subjects (10.7 per cent). In contrast, wishing for a younger innerage was a commonplace phenomenon in India (50.6 per cent of the sample), as well as in China where it occurred the least (36.6 per cent). The study’s findings imply the universal nature of the way human beings (irrespective of culture) perceive and feel about inner‐age, as well as the potential of an inner‐age satisfaction psychographic as a relevant consumer behavior segmentation trait for marketing planners of age‐sensitive products and services who seek to standardize their global branding and distribution.

The purpose of this paper is to study the effect of the electropolishing time of stencil manufacturing parameters and solder‐mask definition methods of PCB pad design parameters on the performance of solder paste stencil printing process for the assembly of 01005 chip components.

During the study, two types of stencils were manufactured for the evaluations: electroformed stencils and electropolished laser‐cut stencils. The electroformed stencils were manufactured using the standard electroforming process and their use in the paste printing process was compared against the use of an electropolished laser‐cut stencil. The electropolishing performance of the laser‐cut stencil was evaluated twice at the following intervals: 100 s and 200 s. The performance of the laser‐cut stencil was also evaluated without electropolishing. An optimized process was established after the polished stencil apertures of the laser‐cut stencil were inspected. The performance evaluations were made by visually inspecting the quality of the post‐surface finishing for the aperture wall and the quality of that post‐surface finishing was further checked using a scanning electron microscope. A test board was used in a series of designed experiments to evaluate the solder paste printing process.

The results demonstrated that the length of the electropolishing time had a significant effect on the small stencil's aperture quality and the solder paste's stencil printing performance. In this study, the most effective electropolishing time was 100 s for a stencil thickness of 0.08 mm. The deposited solder paste thickness was significantly better for the enhanced laser‐cut stencil with electropolishing compared to the conventional electroformed stencils. In this printing‐focused work, print paste thickness measurements were also found to vary across different solder‐mask definition methods of printed circuit board pad designs with no change in the size of the stencil aperture. The highest paste value transfer consistently occurred with solder‐mask‐defined pads, when an electropolished laser‐cut stencil was used.

Due to important improvements in the quality of the electropolished laser‐cut stencil, and based on the results of this experiment, the electropolished laser‐cut stencil is strongly recommended for the solder paste printing of fine‐pitch and miniature components, especially in comparison to the typical laser‐cut stencil. The advantages of implementing a 01005 chip component mass production assembly process include excellent solder paste release, increased solder volume, good manufacture‐ability, fast turnaround time, and greater cost saving opportunities.

To propose a solution procedure to minimize/eliminate tombstoning defects in small chip components with different micro via‐in pad designs for high density module assembly.

Four different micro via‐in pad designs were compared (via‐hole diameter): ultra small via‐in pads (10 μm), small via‐in pads (20 μm) and large via‐in pads (60 μm), as well as designs with no via‐in pads and capped via‐in pads. Two process variables were also evaluated for the goal of achieving a high‐yield assembly solution in micro via‐in pad and lead‐free solder conditions. Potential factors such as the preheat conditions of the reflow profile and stencil aperture size, which might affect tombstoning in components with micro via‐in pads, were investigated.

The results indicated that the micro via‐in pad design significantly increased the tombstoning; thus, tombstoning did not occur in components with both no via‐in pads and capped via‐in pads. Capped via‐in pads exhibited the best results in preventing tombstoning and provided a wide process window for the selection of process parameters. The results showed that tombstoning was found to decrease with both increasing stencil opening ratio and use of reflow profile with long‐preheat condition.

The paper's findings provide certain process guidelines for high density module assemblies with via‐in pad design. The strategy is to prevent tombstoning by adopting capped via‐in pad design if possible when employing micro via‐in pad technology.

The purpose of this paper is to propose that the three‐dimensional information of obstacles should be identified to allow unmanned aerial vehicles (UAVs) to detect and avoid obstacles existing in their flight path.

First, the approximate outline of obstacles was detected using multi‐scale‐oriented patches (MOPS). At the same time, the spatial coordinates of feature points that exist in the internal outline of the obstacles were calculated through the scale‐invariant feature transform (SIFT) algorithm. Finally, the results from MOPS and the results from the SIFT algorithm were merged to show the three‐dimensional information of the obstacles.

As the method proposed in this paper reconstructs only the approximate outline of obstacles, a quick calculation can be done. Moreover, as the outline information is combined through SIFT feature points, detailed three‐dimensional information pertaining to the obstacles can be obtained.

The proposed approach can be used efficiently in GPS‐denied environments such as certain indoor environments.

For the autonomous flight of small UAVs having a payload limit, this paper suggests a means of forming three‐dimensional information about obstacles with images obtained from a monocular camera.