The use of the homomorphic filter technique is described in order to enhance the contrast in the mammographic images, which is adopted to the dyadic wavelet transform. The proposed method has employed the nonlinear enhancement in homomorphic filtering as well as denoising method in the wavelet domains. Experimental results show that the homomorphic filtering method improves the contrast in breast tumor images such that the contrast improvement index is increased by two fold compared to the conventional wavelet-based enhancement technique.

This paper presents a method for detection of calcification, which is an important early sign of breast cancer in mammograms. Since information of calcifications is located in inhomogeneous background and noises, it is hard to be detected. This method uses wavelet packet transform (WPT) for elimination of the background image related to low frequency components. However, very high frequency signals of noises exist with the calcifications and make it hard to suppress them. Since calcification location can be represented as vertical, horizontal, and diagonal edges in time-frequency domain, the edges in spatial domain can be utilized as a filter for noise suppression. Then the image from inverse transform will contain only required information. A free-response operating characteristic (FROC) curve is used to evaluate a performance of proposed method by applying it to thirty images of calcifications. The results show 82.19 percent true positive detection rate at the cost of 6.73 false positive per image.

Confocal laser scanning microscope (CLSM) is capable of delivering a high axial resolution, and with this instrument even thin layers of cells can be imaged in good quality. Therefore, intracellular uptake and distribution properties of photosensitizer zinc coproporphyrin III tetrasodium salt (Zn CP-III) in human lung small cell carcinoma (Ms-1) were examined by using CLSM. In particular, the uptake of Zn CP-III in cytoplasm, plasma membrane, and nucleus was individually evaluated for the first time from fluorescence images obtained by CLSM. The results show that the Zn CP-III content in three cellular areas correlates with extracellular Zn CP-III concentration and time of incubation with Zn CP-III. Furthermore, it was found that the cytoplasmic fluorescence was approximately two times higher than that in the nucleus under all uptake conditions. In addition, cellular accumulation of Zn CP-III was compared with photodynamic cytotoxicity. The photocytotoxicity was to a great extent dependent on the uptake of the photosensitizer. The damaged site of Ms-1 cells induced by photodynamic therapy was plasma membrane. However, the content of Zn CP-III accumulated in cytoplasm was the highest among the three areas, implying that, besides the direct damage on plasma membrane, an oxidative damage to cellular component arose from the cytoplasmic Zn CP-III may also play an important role in photocytotoxicity. The quantitative information obtained in this study will be useful for further investigation of the photocytotoxicity as well as the uptake mechanism of photosensitizer.

This study attempts to demonstrate that activated leukocytes are involved in vascular shut down effect (VSD) in photodynamic therapy (PDT). Hydrogen peroxide (H2O2), a reactive oxygen specie (ROS) that is found in monocytes, was visualized under a confocal laser scanning microscope, and ROS formation was quantified by fluorescence image analysis. The fluorescence intensity was expressed as a gray level graded from 0 to 255. Only the fluorescence derived from monocytes that had ZnCP-III incorporated and were irradiated with an HeNe laser caused increases in the fluorescence distribution over time, while no change of distribution was observed in three other conditions (only Zn CP-III added, only HeNe laser irradiation, or non-treated). The result indicates that the photochemical reaction induced by excitation of a photosensitizer, and ROS was derived from the reaction-stimulated monocytes. The activated monocytes generated ROS themselves and H2O2 was visualized by the DCFH fluorescence method. In conclusion, the result clearly shows that activated monocytes are involved in the VSD effect.

There were researches that measured effort required to understand and adapt components based on the complexity of the component, which is some general criterion related to the intrinsic quality of the component to be adapted and understood. They, however, don't consider significance of the measurement attributes and user must decide reusability of similar components for himself. Therefore, in this paper, we propose a new method that can measure the DOR (Degree Of Reusability) of the components by considering the significance of the measurement attributes. We calculates the relative significance of them by using rough set and integrate the significance with the measurement value by using Sugeno's fuzzy integral. Lastly, we apply our method to the source code components and show through statistical technique that it can be used as the ordinal and ratio scale.

Tree canopies contain various scattering elements such as leaves, branches and trunks, which contribute to complex backscattering, depending on frequency and polarization. In this paper, we propose to use the polarimetric correlation coefficient for classifying trees, forests, and vegetations. The polarimetric correlation coefficient can be derived by the elements of Sinclair scattering matrix. Since the scattering matrix can be defined in any polarization basis, we examined the coefficient in the linear HV, circular LR, and optimum polarization bases. First, the change of correlation coefficient inside trees along the range direction is examined using small trees in a laboratory. The wider the range, the better the index. The coefficient defined in the LR polarization basis showed the largest change within tree canopy, which also contribute to retrieve scattering mechanism. Second, this index for discrimination is applied to polarimetric SAR data sets (San Francisco and Briatia area) acquired by AIRSAR and SIR-C/X-SAR. It is shown that polarimetric correlation coefficient in the LR basis best serves to distinguish tree types.

We suggest the method to recover the 3D shape of an object by using a color image scanner which has three light sources. The photometric stereo is traditional to recover the surface normals of objects using multiple light sources. In this method, it usually assumes distant light sources to make the optical models simple. But the light sources in the image scanner are so close to an object that the illuminant intensity varies with the distance from the light source, therefore these light sources should be modeled as the linear light sources. In this method, by using these models and two step algorithm; the initial estimation by the iterating computation and the optimization by the non-linear least square method, not only the surface normal but also the absolute distance from the light source to the surface can be estimated. By using this method, we can recover the 3D shape more precisely. In the experimental results, the 3D shape of real objects can be recovered and the effectiveness of the proposed method is shown.

This paper investigates the interference suppression effect from much higher rate dedicated physical channels (DPCHs) of a parallel-type coherent multistage interference canceller (COMSIC) with iterative channel estimation (ICE) by laboratory experiments in the transmit-power-controlled W-CDMA reverse link. The experimental results elucidate that when two interfering DPCHs exist with the spreading factor (SF) of 8 and with the ratio of the target signal energy per bit-to-interference power spectrum density ratio (Eb/I0) of fast transmit power control, ΔEb/I0, of -6 dB (which corresponds to 64 simultaneous DPCHs with SF = 64, i.e., the same symbol rate as the desired DPCH), the implemented COMSIC receiver with ICE exhibits a significant decrease in the required transmit signal energy per bit-to-background noise power spectrum density ratio (Eb/N0) at the average bit error rate (BER) of 10-3 (while the matched filter (MF)-based Rake receiver could not realize the average BER of 10-3 due to severe multiple access interference (MAI)). It is also found that the achieved BER performance at the average BER of 10-3 of the COMSIC receiver with the A/D converter quantization of 8 bits in the laboratory experiments is degraded by approximately 1.0 dB and 4.0 dB compared to the computer simulation results, when ΔEb/I0=-6 dB and -9 dB, respectively, due to the quantization error of the desired signal and path search error for the Rake combiner. Finally, we show that the required transmit Eb/N0 at the average BER of 10-3 of the third-stage COMSIC with ICE is decreased by approximately 0.3 and 0.5 dB compared to that of COMSIC with decision-feedback type channel estimation (DFCE) with and without antenna diversity reception, respectively.

As LSIs are two-dimensional structures, the number of external pins increases at a lower rate than the corresponding increase in the number of gates on the LSI. Therefore, the number of flip-flops on a scan path increases as the density of gates on LSIs rises, resulting in longer test application times. In this paper, three novel DFT strategies aimed at reducing test application time are proposed. DFT strategy 1 is a full scan design method with test point insertion, DFT strategy 2 is a partial scan design method, and DFT strategy 3 is a partial scan design method with test point insertion. Experimental results show that these DFT strategies reduced the test application times by 45% to 82% compared with conventional full scan design methods.

In this letter, we focus on achieving the reconfiguration of a multi-rate interference cancellation (IC) scheme via a software radio implementation. In the proposed multi-rate IC scheme, the estimates of each user signal are updated every cancellation stage with more clean signal, which are used in the next stage to yield more reliable estimates.

Electric beam scanning reflector antennas provide beam scanning and pattern control, and can create narrow beams efficiently. However, they are not popular because the beam control circuit is large and difficult to realize. This paper proposes a new BFN configuration for cluster feeding of highly functional scanning antenna. The Enhanced PAttern Control nonswiTch (EPACT) BFN simplifies the beam control circuit and its control algorithm by using a fast Fourier transform (FFT) circuit, phase shifters, and a power divider. Furthermore, this paper proposes a design technique that uses modules to implement the FFT circuit and a method that optimizes amplifier placement to improve antenna efficiency. The design technique facilitates the manufacture of large-scale FFT circuits. The optimized amplifier location improves the antenna efficiency by eliminating the partial concentration of signal power.

Most of the current research is focused on the row-column scanning keyboard interface for English letter and number input. At the present time, there are insufficient methods to control the computer mouse effectively. In this study, a categorized row-column scanning computer interface is developed to improve the conventional single key-in row-column scanning method. The beneficial developments include: speed enhancement by categorizing radicals of keyboard, input control of mouse, and multiple selection of input methods such as surface electromyographic (SEMG) control, breath pressure sensibility control with puff, force sensibility control, infrared sensibility control and single key-in control. Meanwhile, an enhancement software package is developed to increase the row-column scanning keyboard capabilities and to upgrade the completeness of the computer mouse for the disabled persons to control the operation of data entry and the associated implementation better.

We present a scalable parallel rasterizer based on our interleaved scanline rasterization. The sorting overhead of a conventional scanline-based parallel rendering approach has been studied and removed by implementing a scanline assignment hardware. All advantages of the scanline-based parallel rendering are kept such that a good scalability and a small memory usage are achieved. Our architecture is evaluated precisely by a discrete event-based simulation, and the rendering performance and utilization are shown for a various number of rasterizers. The simulation results show more than 8 Mtriangles/s of performance with 64 rasterization engines running at 10 MHz.

This paper presents a DFT controller called as a TCU (Test Control Unit), which considerably improves the efficiency of the instruction-based functional test. Internal program/data buses are completely controllable and observable by the TCU during the test cycle. Diverse test modes of the TCU can increase the test efficiency and also provide complete access to program/data memories for functional test.

A simple embedded lossless wavelet-based image coding algorithm called Successive Partition Zero Coder (SPZC), which uses hybrid bit scanning and non-causal adaptive context modelling, is proposed. By successive partition the wavelet coefficients in the spatial-frequency domain, the coefficients are ordered based on their absolute range. The prioritized coefficients are quantized in a successive approximation manner to generate a binary sequence, which is divided into subsources and encoded by arithmetic coder with non-causal adaptive context modelling. This method is suited for progressive image transmission (PIT). Experimental results show that SPZC outperforms other state-of-the-art coders such as SPIHT, CREW and LJPEG, but slightly inferior to ECECOW and CALIC in lossless mode. SPZC is simple in both context modelling and implementation.

In [3], the decision feedback channel estimation (DFCE) for M-ary orthogonal modulation in direct sequence/code division multiple access (DS/CDMA) systems was proposed. However, the performance of the DFCE in the multiuser environment is severely degraded due to multiple access interference (MAI). In this letter, to overcome this problem, we modify the DFCE as multistage configurations using a multistage parallel interference cancellation (PIC) scheme. According to the results of our simulations, the performance of coherent demodulation using the proposed multistage DFCE is significantly improved in comparison with conventional demodulation in [3].

In SDMA, a spatial domain interference canceller applying a multistage processing concept to the MMSE multibeam adaptive array has an attractive feature. Weak power signals strongly interfered can be detected in the succeeded stages after removing other strong power signals which are already detected. This idea can be enhanced to the reference timing estimation required in the MMSE algorithm. In this paper, the spatial domain interference canceller introducing multistage timing estimation is proposed and its performance is evaluated by computer simulations. The results show that the timing estimation performance highly improved.

This paper proposes an automatic system which can perform the entire diagnostic process from the extraction of the liver to the recognition of a tumor. In particular, the proposed technique uses shape information to identify and recognize a lesion adjacent to the border of the liver, which can otherwise be missed. Because such an area is concave like a bay, morphological operations can be used to find the bay. In addition, since the intensity of a lesion can vary greatly according to the patient and the slice taken, a decision on the threshold for extraction is not easy. Accordingly, the proposed method extracts the lesion by means of a Fuzzy c-Means clustering technique, which can determine the threshold regardless of a changing intensity. Furthermore, in order to decrease any erroneous diagnoses, the proposed system performs a 3-D consistency check based on three-dimensional information that a lesion mass cannot appear in a single slice independently. Based on experimental results, these processes produced a high recognition rate above 91%.

Error concealment is an essential part of reliable video communication systems because transmission errors are inevitable even when the coded bitstream is highly protected. The problem of temporal EC can be factored into two parts regarding candidate motion vectors (MVs) employed and the matching criterion to evaluate the fitness of each candidate MV. In order to obtain more faithful EC results, this paper proposes a novel iterative EC algorithm, in which an efficient way to provide candidate MVs and a new fitness measure are presented. The proposed approach for candidate MVs systematically utilizes all the available neighboring MVs by exploiting a well-known spatiotemporal correlation of block MVs. Also, in order to remove the dependency of a damaged block's quality of concealment on the already concealed adjacent blocks, we develope a new matching criterion. The objective of the proposed fitness measure is to minimize the total boundary matching errors induced by the whole corrupted blocks. Simulations performed using an H.263 codec demonstrate a significant improvement on the subjective and objective concealed video qualities, especially when the corrupted area is wider than a single row of coding blocks.

This paper describes a method for classification of hematoxylin and eosin (HE)-stained breast tumor images into benign or malignant using the adaptive searching ability of artificial organisms. Each artificial organism has some attributes, such as, age, internal energy and coordinates. In addition, the artificial organism has a differentiation function for evaluating "malignant" or "benign" tumors and the adaptive behaviors of each artificial organism are evaluated using five kinds of texture features. The texture feature of nuclei regions in normal mammary glands and that of carcinoma regions in malignant tumors are treated as "self" and "non-self," respectively. This model consists of two stages of operations for detecting tumor regions, the learning and searching stages. At the learning stage, the nuclei regions are roughly detected and classified into benign or malignant tumors. At the searching stage, the similarity of each organism's environment is investigated before and after the movement for detecting breast tumor regions precisely. The method developed was applied to 21 cases of test images and the distinction between malignant and benign tumors by the artificial organisms was successful in all cases. The proposed method has the following advantages: the texture feature values for the evaluation of tumor regions at the searching stage are decided automatically during the learning stage in every input image. Evaluation of the environment, whether the target pixel is a malignant tumor or not, is performed based on the angular difference in each texture feature. Therefore, this model can successfully detect tumor regions and classify the type of tumors correctly without affecting a wide variety of breast tumor images, which depends on the tissue condition and the degree of malignancy in each breast tumor case.