• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.30 no.2
• /
• pp.41-46
• /
• 2020

The characteristics of the residual stress on the types of the substrate was investigated with adjusting the V/III ratio during GaN growth via the HVPE method. GaN single crystal layers were grown on a sapphire substrate and a GaN template under the conditions of V/III ratio 5, 10, and 15, respectively. During GaN growth, multiple hexagonal pits in GaN single crystal were differently revealed in accordance with growth condition and substrate type, and their distribution and depth were measured via optical microscopy(OM) and white light interferometry(WLI). As a result, it was confirmed that the distribution area and depth of hexagonal pit tended to increase as the V/III ratio increased. Moreover, it was found that the residual stress in GaN single crystal decreased as the distribution area and depth of the pit increased through measuring micro Raman spectrophotometer. In the case of GaN growth according to substrate type, the GaN on GaN template showed lower residual stress than the GaN grown on sapphire substrate.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.4
• /
• pp.573-581
• /
• 2006

This experiment was conducted to determine the effects of supplemental methionine, lysine, choline, and sulfur on laying performance, metabolic parameters, and egg quality of hens fed diets containing sorghum (Sorghum vulgare) during the peak laying period. Lohman layers (n = 144), 30-wk of age as 6 replicate cages of 4 hens, were allocated randomly to receive basal diets containing either 22% corn (B) or 22% sorghum (BS) and diets BS plus 0.57% methionine, 0.66% lysine, 0.47% choline, or 0.05% sulfur for 98 d. Feed intake (FI) and egg production (EP) were recorded daily, egg weight (EW) was measured bi-weekly, and body weight (BW) was measured monthly. A sample of 12 eggs from each experimental group was collected every month to evaluate egg quality. At the end of the experiment, blood samples were collected for metabolite concentrations. Data were analyzed using one-way ANOVA as repeated measures and significant differences between the experimental groups were assessed using Duncan's Multiple Range test. Partial replacement of corn with sorghum in the basal diet did not affect BW, EP, and FCR but increased FI by 5.7% and EW by 2.4%. The effects of additives on laying performance were variable. Except for serum total protein (STP) concentration, other metabolic parameters were not affected by partial replacement of corn with sorghum in the basal diet. Hens fed diet BS had lower SPT concentration than hens fed diet B. Except for methionine supplementation, other supplements ameliorated depression in STP concentration. The additives did not affect other metabolic parameters. Egg quality responses to the experimental diets were also variable. Partial replacement of corn with sorghum in the basal diet did not affect eggshell characteristics (both thickness and stiffness), whereas it had variable effects on inner egg quality parameters (increased yolk index, depressed yolk color, and unaltered albumen index and Haugh unit). In conclusion, laying hen diets could include low-tannin sorghum (0.26%) up to 22% without necessitating extra supplements to overcome compromised performance.

• Korean Journal of Remote Sensing
• /
• v.33 no.5_2
• /
• pp.741-750
• /
• 2017

The objective of this study was to estimate corn and soybean yield in Illinois and Iowa in USA using satellite and meteorological data. MODIS products for NDVI were downloaded from a NASA website. Each layer was processed to convert projection and extract layers for NDVI. Relations of NDVI from 2002 to 2012 with corn and soybean yield were investigated to find informative days for rice yield estimation. Weather data for the county of study state duration from 2002 to 2012 to correlate crop yield. Multiple regression models based on MODIS NDVI and rainfall were made to estimate corn and soybean yields in study site. Corn yields estimated for 2013 were $10.17ton\;ha^{-1}$ in Illinois, $10.21ton\;ha^{-1}$ in Iowa and soybean yields estimated were $3.11ton\;ha^{-1}$ in Illinois, $2.58ton\;ha^{-1}$ in Iowa, respectively. Corn and Soybean yield distributions in 2013 were mapped to show spatial variability of crop yields of the Illinois and Iowa state.

• Korean Journal of Soil Science and Fertilizer
• /
• v.17 no.1
• /
• pp.77-81
• /
• 1984

Paddy soil samples were collected from the plow layers of 19 soil series distributed in Yeongnam district to determine the relationship between soil urease activity and other soil characteristics. The results obtained were summarized as follows: 1. Simple correlation analyses showed that the urease activity was positively related with available $P_2O_5(r=.844^{**})$, potassium activity ratio($r=0.762^{**}$), available $SiO_2(r=.580^{**})$ and $SiO_2$/O.M ratio($r=0.591^{**}$). 2. Among soil chemical properties which had positive linear correlations with soil urease activity, the content of available $P_2O_5$ in soil had the highest contribution to the multiple regression equation of soil urease activity. 3. The activity of soil urease was especially lower in sandy texture than in clayey paddy soils, and a tendency was observed that the heavier soil textures the higher activity of soil urease. 4. Relatively well drained soils had the higher activity of soil urease while the soils in "poorly drained" had remarkably lower activity of soil urease. 5. The soils in higher classes of paddy soil equitability group had higher activities of soil urease.

• Journal of Korea Multimedia Society
• /
• v.12 no.7
• /
• pp.903-912
• /
• 2009

There are still many difficulties in developing techniques for modifying or transforming the flickering of motion capture data or in modifying motion capture data in such a way that suits the animation timing sheet. There is a problem in the existing method of modifying motion capture data. It requires almost same time as in the key frame animation work by a very skilled animator or even more time in modifying. It is believed that this kind of problem can be a basis for a more effective problem-solving method through creating the key animation data node and direct blend layer and replacement layer nodes. This study presents a new method which enables to modify animation data in a nonlinear way without modifying the existing animation data by creating an animation layer node for a direct connection to the animation node. 'Maya' API will be utilized in order to realize this method and the research range will be limited to 'Maya' 3D software which is generally used in motion picture and animation films. According to the results of this study, the new method is much more intuitive than the nonlinear one and does not require the preceding working of making animation clips. In addition, it has enabled to modify flickering and to extract key frames, and due to the compatibility with other programs, it has been possible to modify motion capture data by creating a direct layer node. Finally, in this study, the existing method of modifying animation will be examined, compared and analyzed.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.19 no.3
• /
• pp.16-28
• /
• 2016

Advancing geo-spatial web technologies and their applications require compatible and interoperable heterogeneous browsers and platforms. Reduction of common or supporting components for web-based system development is also necessary. If properly understood and applied, OGC-based standards can be utilized as effective solutions for these problems. Thus, OGC standards are central to the design and development of web-based geo-spatial systems, and are particularly applicable to web services, which contain data processing modules. However, the application for OGC WPS 2.0 is at an early stage as compared with other OGC standards; thus, this study describes a test implementation of a web-based geo-spatial processing system with OGC WPS 2.0 focused on asynchronous processing functionality. While a binary thresholding algorithm was tested in this system, further experiments with other processing modules can be performed on requests for many types of processing from multiple users. The client system of the implemented product was based on open sources such as jQuery and OpenLayers, and server-side running on Spring framework also used various types of open sources such as ZOO project, and GeoServer. The results of geo-spatial image processing by this system implies further applicability and extensibility of OGC WPS 2.0 on user interfaces for practical applications.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.25 no.2
• /
• pp.76-93
• /
• 2013

The hydrodynamics in the Youngsan River Estuary has changed due to coastal developments such as the estuary dam and two tidal barriers. As the freshwater discharge is artificially controlled, the circulation pattern is different from those of natural estuaries and the river-born sediment supply is restricted. 3D numerical modeling system EFDC was applied to investigate the sediment transport pattern and budget in summer with river floods. The real-time driving forces and the fluvial sediment discharges from the watershed modeling were assigned for the simulation period. The size classes of sand, silt and clay were adopted based on the grain-size distribution of bottom sediments. The modeling results were calibrated and validated with the observed tides, tidal currents and suspended sediment concentrations. The suspended sediments are transported to the offshore at surface layer, whereas upstream toward the dam at mid- and bottom layers in August 2011. The characteristic estuarine circulation induced by the freshwater discharge from the dam, causes the deposition of silt-sized sediments on the whole and the sustained suspension of clay-sized sediments.

• KIPS Transactions on Computer and Communication Systems
• /
• v.2 no.9
• /
• pp.381-392
• /
• 2013

During the last decade, the multitude of advances attained in terminal computers, along with the introduction of mobile hand-held devices, and the deployment of high speed networks have led to a recent surge of interest in Quality of Service (QoS) for video applications. The main difficulty is that mobile devices experience disparate channel conditions, which results in different rates and patterns of packet loss. One way of making more efficient use of network resources in video services over wireless channels with heterogeneous characteristics to heterogeneous types of mobile device is to use a scalable video coding (SVC). An SVC divides a video stream into a base layer and a single or multiple enhancement layers. We have to ensure that the base layer of the video stream is successfully received and decoded by the subscribers, because it provides the basis for the subsequent decoding of the enhancement layer(s). At the same time, a system should be designed so that the enhancement layer(s) can be successfully decoded by as many users as possible, so that the average QoS is as high as possible. To accommodate these characteristics, we propose an efficient transmission scheme which incorporates SVC-aware dual-channel repetition to improve the perceived quality of services. We repeat the base-layer data over two channels, with different characteristics, to exploit transmission diversity. On the other hand, those channels are utilized to increase the data rate of enhancement layer data. This arrangement reduces service disruption under poor channel conditions by protecting the data that is more important to video decoding. Simulations show that our scheme safeguards the important packets and improves perceived video quality at a mobile device.

• The magazine of the Korean Society for Advanced Composite Structures
• /
• v.5 no.2
• /
• pp.26-31
• /
• 2014

This invention is purposed to provide an innovative solution for the inside of roof structures, which is cultural assets. The Asian old houses generally have several layered roofs on top of the structures. If a fire has started inside of the roof, it is hard to be extinguished before eliminating all the upper layers of the roof. This invention provides pre constructed embedded pipes, which is flammable and easy to be dissolved by the fire. The material of pipe is composed of rubbers, of which the combustion point is so low that the extinguishing of initial fire is possible without additional fire service. The inside of pipe is filled with halon gas. If the filled gas is consumed after ignited by fire, additional fire extinguishing water is supplied. If the flexible pipes are totally combusted by a big fire, the sprinkler at the end of inflexible pipe will work continuously, which is located between flexible and inflexible pipes. The extinguishing pipe network is suggested as dividing whole roof as multiple sections for a swift fire extinguishing in case of intentional or natural fire attack to our invaluable cultural assets.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.1
• /
• pp.114-123
• /
• 2018

This paper concerns a design and learning method of softmax function neural networks based on K-means clustering. The partial discharge data Information is preliminarily processed through simulation using an Epoxy Mica Coupling sensor and an internal Phase Resolved Partial Discharge Analysis algorithm. The obtained information is processed according to the characteristics of the pattern using a Motor Insulation Monitoring System program. At this time, the processed data are total 4 types that void discharge, corona discharge, surface discharge and slot discharge. The partial discharge data with high dimensional input variables are secondarily processed by principal component analysis method and reduced with keeping the characteristics of pattern as low dimensional input variables. And therefore, the pattern classifier processing speed exhibits improved effects. In addition, in the process of extracting the partial discharge data through the MIMS program, the magnitude of amplitude is divided into the maximum value and the average value, and two pattern characteristics are set and compared and analyzed. In the first half of the proposed partial discharge pattern classifier, the input and hidden layers are classified by using the K-means clustering method and the output of the hidden layer is obtained. In the latter part, the cross entropy error function is used for parameter learning between the hidden layer and the output layer. The final output layer is output as a normalized probability value between 0 and 1 using the softmax function. The advantage of using the softmax function is that it allows access and application of multiple class problems and stochastic interpretation. First of all, there is an advantage that one output value affects the remaining output value and its accompanying learning is accelerated. Also, to solve the overfitting problem, L2-normalization is applied. To prove the superiority of the proposed pattern classifier, we compare and analyze the classification rate with conventional radial basis function neural networks.