• Journal of Broadcast Engineering
• /
• v.19 no.3
• /
• pp.342-354
• /
• 2014

This paper deals with digital watermarking methods to protect ownership of image with targeting the ultra-high multi-view or free-view image service in which an arbitrary viewpoint image should be rendered at the user side. The main purpose of it is not to propose a superior method to the previous methods but to show how difficult to construct a watermarking scheme to overcome the viewpoint translation attack. Therefore we target the images with various attacks including viewpoint translation. This paper first shows how high the error rate of the extracted watermark data from viewpoint-translated image by basic schemes of the method using 2DDCT(2D discrete cosine transform) and the one using 2DDWT(2D discrete wavelet transform), which are for 2D image. Because the difficulty in watermarking for the viewpoint-translated image comes from the fact that we don't know the translated viewpoint, we propose a scheme to find the translated viewpoint, which uses the image and the corresponding depth information at the original viewpoint. This method is used to construct the two non-blind watermarking methods to be proposed. They are used to show that recovery of the viewpoint affect a great deal of the error rate of the extracted watermark. Also by comparing the performances of the proposed methods and the previous ones, we show that the proposed ones are better in invisibility and robustness, even if they are non-blind.

• Journal of Korean Society for Geospatial Information Science
• /
• v.7 no.2 s.14
• /
• pp.123-132
• /
• 1999

With the rapid increases of the amount of data and computing, the parallelization of the computing algorithm becomes necessary more than ever. However the parallelization had been conducted mostly in a super-computer until the rod 1990s, it was not for the general users due to the high price, the complexity of usage, and etc. A new concept for the parallel processing has been emerged in the form of K-clustering form the late 1990s, it becomes an excellent alternative for the applications need high computer power with a relative low cost although the installation and the usage are still difficult to the general users. The mapping algorithms (cut, join, resizing, warping, conversion from raster to vector and vice versa, etc) in GIS are well suited for the parallelization due to the characteristics of the data structure. If those algorithms are manipulated using PC-clustering, the result will be satisfiable in terms of cost and performance since they are processed in real flu with a low cos4 In this paper the tools and the libraries for the parallel processing and PC-clustering we introduced and how those tools and libraries are applied to mapping algorithms in GIS are showed. Parallel programs are developed for the mapping algorithms and the result of the experiments shows that the performance in most algorithms increases almost linearly according to the number of node.

• Smart Media Journal
• /
• v.1 no.3
• /
• pp.36-42
• /
• 2012

Recently, the smart applications, such as smart phone and smart TV, become a hot issue in IT consumer markets. In particular, the smart TV provides 3D video services, hence efficient coding methods for 3D video data are required. Three-dimensional (3D) video involves stereoscopic or multi-view images to provide depth experience through 3D display systems. Binocular cues are perceived by rendering proper viewpoint images obtained at slightly different view angles. Since the number of viewpoints of the multi-view video is limited, 3D display devices should generate arbitrary viewpoint images using available adjacent view images. In this paper, after we explain a view synthesis method briefly, we propose a new algorithm to compensate view synthesis errors around object boundaries. We describe a 3D warping technique exploiting the depth map for viewpoint shifting and a hole filling method using multi-view images. Then, we propose an algorithm to remove boundary noises that are generated due to mismatches of object edges in the color and depth images. The proposed method reduces annoying boundary noises near object edges by replacing erroneous textures with alternative textures from the other reference image. Using the proposed method, we can generate perceptually inproved images for 3D video systems.

• The Korean Journal of Quaternary Research
• /
• v.3 no.1
• /
• pp.17-34
• /
• 1989

The distribution characteristics of incised meander river are analysed concerning topography, geology, stream order and altitude. Additionally geomorphological development of the Korean peninsular is considered with incised meander. The main findings are as follows: 1. The incised meander is intensively distributed on the west and north slope of T'aebak and Sobaek mountain range, but sparsely distributed on the opposite slopes. 2. Geologically, the occurrence rate of incised meander is high orderly as follows: Joseon supergroup, Pyeongan supergroup, Daedong supergroup metamorphic rock, Gyeongsang supergroup, and granite. The incised meander is developed well on the following conditions: hard rocks against weathering, stratified structure, geologic arrange across the river channel and contacting zone of geological formations. 3. The higher stream orders are, the higher occurrence of incised meander is. 4. Comparing the altitude of present river bed with the summit level of restored map, it is supposed that the incised meander rivers have been dissected about 300-500m down ward. 5. Considering the distribution characteristic of incised meander, it is suggested that not only T'aebak mountain range but Sobaek mountain range is the axis of asymmetrical up-warping in the Korean peninsular. 6. Considering the distribution characteristic of incised meander on the restored map and the stream order, it seems that present incised meander channel was inherited from antecedent meander river that had flowed on High and Middle level erosion surface. But the channel pattern has been modified.

• Journal of Korean Society of Steel Construction
• /
• v.15 no.3
• /
• pp.231-239
• /
• 2003

Many box girder bridges have been constructed during the past several decades due to their large bending and torsional rigidities as well as aesthetic considerations. However, box girders have shortcoming in that the cross section distorts under an eccentric loading and warps out of the section plane. Therefore, in order to reduce distortional stresses such as distortional warping and transverse bending normal stresses, diaphragms were generally installed in the box girders. Shapes of the diaphragms in steel-box-girder bridges constructed up to date were solid-plate, frame, and truss types. The objectives of this study using parametric study were to evaluate the appropriate stiffness ratio of intermediate diaphragms and then to propose the effective spacing and numbers of intermediate diaphragms based on the evaluated stiffness ratio. Target bridges for this study were straight continuous span bridges with a single-cell steel box section. The parameters for the parametric study were the shape of box section, the span numbers, the equivalent span length, the stiffness of intermediate diaphragms, and the spacing of intermediate diaphragms. From the results of the parametric study, the effective spacing and numbers as well as the stiffness ratio of the intermediate diaphragms will be presented.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.02a
• /
• pp.241-241
• /
• 2012

Semiconductor industry has been taking the advantage of improvements in process technology in order to maintain reduced device geometries and stringent performance specifications. This results in semiconductor manufacturing processes became hundreds in sequence, it is continuously expected to be increased. This may in turn reduce the yield. With a large amount of investment at stake, this motivates tighter process control and fault diagnosis. The continuous improvement in semiconductor industry demands advancements in process control and monitoring to the same degree. Any fault in the process must be detected and classified with a high degree of precision, and it is desired to be diagnosed if possible. The detected abnormality in the system is then classified to locate the source of the variation. The performance of a fault detection system is directly reflected in the yield. Therefore a highly capable fault detection system is always desirable. In this research, time series modeling of the data from an etch equipment has been investigated for the ultimate purpose of fault diagnosis. The tool data consisted of number of different parameters each being recorded at fixed time points. As the data had been collected for a number of runs, it was not synchronized due to variable delays and offsets in data acquisition system and networks. The data was then synchronized using a variant of Dynamic Time Warping (DTW) algorithm. The AutoRegressive Integrated Moving Average (ARIMA) model was then applied on the synchronized data. The ARIMA model combines both the Autoregressive model and the Moving Average model to relate the present value of the time series to its past values. As the new values of parameters are received from the equipment, the model uses them and the previous ones to provide predictions of one step ahead for each parameter. The statistical comparison of these predictions with the actual values, gives us the each parameter's probability of fault, at each time point and (once a run gets finished) for each run. This work will be extended by applying a suitable probability generating function and combining the probabilities of different parameters using Dempster-Shafer Theory (DST). DST provides a way to combine evidence that is available from different sources and gives a joint degree of belief in a hypothesis. This will give us a combined belief of fault in the process with a high precision.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.02a
• /
• pp.433-433
• /
• 2012

As the requirement in patterning geometry continuously shrinks down, the termination of etch process at the exact time became crucial for the success in nano patterning technology. By virtue of real-time optical emission spectroscopy (OES), etch end point detection (EPD) technique continuously develops; however, it also faced with difficulty in low open ratio etching, typically in self aligned contact (SAC) and one cylinder contact (OCS), because of very small amount of optical emission from by-product gas species in the bulk plasma glow discharge. In developing etching process, one may observe that coupon test is being performed. It consumes costs and time for preparing the patterned sample wafers every test in priority, so the coupon wafer test instead of the whole patterned wafer is beneficial for testing and developing etch process condition. We also can observe that etch open area is varied with the number of coupons on a dummy wafer. However, this can be a misleading in OES study. If the coupon wafer test are monitored using OES, we can conjecture the endpoint by experienced method, but considering by data, the materials for residual area by being etched open area are needed to consider. In this research, we compare and analysis the OES data for coupon wafer test results for monitoring about the conditions that the areas except the patterns on the coupon wafers for real-time process monitoring. In this research, we compared two cases, first one is etching the coupon wafers attached on the carrier wafer that is covered by the photoresist, and other case is etching the coupon wafers on the chuck. For comparing the emission intensity, we chose the four chemical species (SiF2, N2, CO, CN), and for comparing the etched profile, measured by scanning electron microscope (SEM). In addition, we adopted the Dynamic Time Warping (DTW) algorithm for analyzing the chose OES data patterns, and analysis the covariance and coefficient for statistical method. After the result, coupon wafers are over-etched for without carrier wafer groups, while with carrier wafer groups are under-etched. And the CN emission intensity has significant difference compare with OES raw data. Based on these results, it necessary to reasonable analysis of the OES data to adopt the pre-data processing and algorithms, and the result will influence the reliability for relation of coupon wafer test and whole wafer test.

• Journal of Conservation Science
• /
• v.34 no.5
• /
• pp.379-385
• /
• 2018

This study examined the condition of degraded plastic artifacts and conducted materials assessments for conservation treatment. The properties and bond characteristics of five types of adhesives(EVA, PVAc, Cyanoacrylate) were evaluated to select the adhesive most suitable for conservation treatment. The degradation of plastic artifacts caused cracks, peelings, and surface warping. According to the FT-IR analysis, the synthetic resin used in the artifact was estimated to EVA type. The properties of the adhesives were evaluated through acidity, and hardness measurements. The results showed that acidity varies with the type of adhesive, and that the hardness of PVAc was higher than those of EVA. On comparing the bond characteristics of the samples after artificial degradation, it was found that PVAc and Cyanoacrylate increased the chromaticity and hardness of the samples, while EVA was the most stable with relatively little change. Thus, EVA was confirmed to be the most suitable materials for conservation treatment of degraded plastic artifacts. In this study, as the experiment of treatment materials based on actual artifact, it is expected that it could be used a basis research for conservation treatment of plastic artifacts.

• Applied Chemistry for Engineering
• /
• v.17 no.6
• /
• pp.604-608
• /
• 2006

Polymer composites for measuring the radioactive contamination are prepared by coating ZnS(Ag) powders as a scintillator on polysulfone base layer. The composites consist of the active layer for a scintillation reaction with radioactive wastes and the transparent support layer for transmittance of light photons emitted by scintillation in the active layer. The binding of the active layer, including ZnS(Ag), on the support layer is proceeded via coating with polysulfone as a binder, without any extra adhesive. The coating was obtained by either casting via a Doctor Blade as applicator or screen printing. The prepared composites feature a monolithic structure, resulting in the complete adhesion between two layers. The composite prepared by the casting technique using an applicator holds a good detection efficiency in measuring the alpha radionuclide, but its structure becomes fragile because of warping in morphology. On the contrary, the composite prepared by the screen printing shows a good detection capacity as well as a good stability in a mechanical shape.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.13 no.1
• /
• pp.35-43
• /
• 2009

Two types of piloti-type high-rise RC building structures having irregularity in the lower two stories were selected as prototypes, and nonlinear time history analysis was performed using OpenSees to verify the analysis technique and to investigate the seismic capacity of those buildings. One of the buildings studied had a symmetrical moment-resisting frame (BF), while the other had an infilled shear wall in only one of the exterior frames (ESW). A fiber model, consisting of concrete and reinforcing bar represented from the stress-strain relationship, was adapted and used to simulate the nonlinearity of members, and MVLEM (Multi Vertical Linear Element Model) was used to simulate the behavior of the wall. The analytical results simulate the behavior of piloti-type high-rise RC building structures well, including the stiffness and yield force of piloti stories, the rocking behavior of the upper structure and the variation of the axial stiffness of the column due to variation in loading condition. However, MVLEM has a limitation in simulating the abrupt increasing lateral stiffness of a wall, due to the torsional mode behavior of the building. The design force obtained from a nonlinear time history analysis was shown to be about $20{\sim}30%$ smaller than that obtained in the experiment. For this reason, further research is required to match the analytical results with real structures, in order to use nonlinear time history analysis in designing a piloti-type high-rise RC building.