This paper presents a multi-bit continuous-time sigma-delta (ΣΔ) audio ADC employing 3-level unit-elements with 1 st -order mismatch shaping. An input common-mode (CM) stabilization circuit is used to accommodate a 7 V common-mode voltage range when DC coupled. The converter uses a tuning technique which allows a wide range of clock speed, RC variation while mitigates the inter-symbol interference and clock jitter sensitivity issues in the feedback current steering DAC. The ADC achieves 111 dB A-weighted SNR, -98 dB THD+N in the 22 kHz bandwidth, while consumes a total of 2.4 mW from a 3.3 V supply, and occupies ~0.5 mm 2 in a 0.18 um CMOS process.

There are many recommendation systems available to provide users with personalized services. Among them, the most frequently used in electronic commerce is 'collaborative filtering', which is a technique that provides a process of filtering customer information for the preparation of profiles and making recommendations of products that are expected to be preferred by other users, based on such information profiles. Collaborative filtering systems, however, have in their nature both technical issues such as sparsity, scalability, and transparency, as well as security issues in the collection of the information that becomes the basis for preparation of the profiles. In this paper, we suggest a movie recommendation system, based on the selection of optimal personal propensity variables and the utilization of a secure collaborating filtering system, in order to provide a solution to such sparsity and scalability issues. At the same time, we adopt 'push attack' principles to deal with the security vulnerability of collaborative filtering systems. Furthermore, we assess the system's applicability by using the open database MovieLens, and present a personal propensity framework for improvement in the performance of recommender systems. We successfully come up with a movie recommendation system through the selection of optimal personalization factors and the embodiment of a safe collaborative filtering system

Process technologies such as Personal Software ProcessSM (PSP) and Team Software ProcessSM (TSP) provide a good foundation for Six Sigma applications in business. Business approaches using Six Sigma provide methods for process improvement and analysis to achieve the goals of the PSP/TSP. This article discusses a framework with which software engineers and project managers can quantitatively manage software projects for improving the processes by applying Six Sigma in conjunction with PSP/TSP. Sejun Kim, BISTel

Hierarchical clustering is an important and powerful but computationally extensive operation. Its complexity motivates the exploration of highly parallel approaches such as Adaptive Resonance Theory (ART). Although ART has been implemented on GPU processors, this paper presents the first hierarchical ART GPU implementation we are aware of. Each ART layer is distributed in the GPU's multiprocessors and is trained simultaneously. The experimental results show that for deep trees, the GPU's performance advantage is significant.

Automotive and consumer multi-channel 24 b audio systems have demanded low-cost digital-to-analog converters (DACs) which offer wide dynamic range, high linearity, small die size, and low power consumption such that the system can be housed in a small low-cost plastic package. Several 120 dB SNR audio ΔΣ DACs have been reported using either switched-capacitor or continuous-time techniques. This paper presents a continuous time (CT) area optimized multibit DAC which achieves 120dB SNR and 100dB THD+N at 21.5mW/chan nel. This performance is achieved by using a new 3-level rotational data shuffling scheme which achieves small area and low digital activity at low signal level, and by applying low-power low-noise analog techniques.

$ZnGa_2O_4$ powder were prepared by combustion method and $Mn^{2+}$ ions, a green luminescence activator, and $Cr^{3+}$ ions, a red luminescence activator were separately doped into $ZnGa_2O_4$. The characteristics of the synthesized nano powder were investigated by means of X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and photoluminescence (PL). The various $ZnGa_2O_4$ peaks, with the (311) main peak, appeared at all sintering temperature XRD patterns. The PL specctrums of $ZnGa_2O_4$ powder showed main peak of 425 nm, and maximum intensity at the sintering temperature of $1200^{\circ}C$. SEM images shown that nano sized particles(about 200 nm) were of spherical shape. The characteristics of $ZnGa_2O_4$ containing 0.004 mol $Mn^{2+}$(505 nm, green) and $ZnGa_2O_4$ containg 0.002 mol $Cr^{3+}$ (696 nm, red) were shown to be the best.

Prior coverage-based test case prioritization techniques aim to increase fault detection rates by ordering the test cases according to some coverage criteria. However, in practice, since detected faults are typically removed, test cases that already covered the previously executed areas might not perform well as expected, irrespective of their coverage. In this case, the ordering of test cases based on coverage information might not be effective. In this paper, we introduce a new test case prioritization technique that considers both coverage and historical fault information by incorporating fault localization technique. Using the historical fault detection information of test cases, our approach adjusts the priorities of fault-found test cases while maintaining test cases with high coverage in high priority. Our approach can reduce the total cost of executing entire test suite(s) and enables to detect faults earlier in a testing process by improving the testing effectiveness compared to the prior coverage-based techniques.

This paper investigates an adaptive practice on software reliability in frequent requirement modifications. According to the conventional software development processes, software requirements are specified and locked at the early stage of software life cycle. As a project progresses, the requirements can be added and modified to reflect customers needs. However, it can be an obstacle to activities for software reliability engineered process if they are changed frequently. Software is developed in accordance with the requirements. If the frequency of software requirement modifications is high, the software is liable to be error-prone. It also makes the software reliability estimation activities reconfigurable. Therefore, we propose an adaptive approach to estimate software reliability which is based on IEEE Std. 1633. We show why the adaptive approach is necessary when software requirements are changed frequently through a case study.

For this study, terbium-doped yttrium aluminum garnet (YAG:Tb) phosphor powders were prepared via the combustion process using the 1:1 ratio of metal ions to reagents. The characteristics of the synthesized nano powder were investigated by means of X-ray diffraction (XRD), scanning electron microscope (SEM), and photoluminescence. Single-phase cubic YAG:Tb crystalline powder was obtained at 800 °C by directly crystallizing it from amorphous materials, as determined by XRD techniques. There were no intermediate phases such as yttrium aluminum perovskite (YAlO3) and yttrium aluminum monoclinic (Y4Al2O9) observed in the sintering process. The SEM image showed that the resulting YAG:Tb powders had uniform sizes and good homogeneity. With the increase in the sintering temperature, the grain size increased. The photoluminescence spectra of the YAG:Tb nanoparticles were investigated to determine the energy level of electron transition related to luminescence processes. There were three peaks in the excited spectrum, and the major one was a broad band of around 274 nm. Also, the YAG:Tb nanoparticles showed two emission peaks in the range of 450 × 500 and 525 × 560 nm, respectively, and had maximum intensity at 545 nm.

MT reliability of MANOS cell was examined from cell array. Lots of retention tail bits occurred even at RT. The fail cells were classified as the manner of q-loss. Defective cell lost abundant charge at early stage, while the q-loss rate of worse cell was faster and lasted in a certain period. Si-cluster in our nitride was supposed to make the worse cell, and this cell redeemed its retention capability by reducing shallow trap in Si-rich nitride.

In this study, nanocrystalline zinc gallate (ZnGa2O4) phosphors were prepared by a precipitation method using aqueous ammonia as the precipitant. This method enabled the low temperature formation of phosphors with spherical shape. The samples were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and cathodoluminescence (CL). The highest diffraction intensity was observed for the sample with a metal ion concentration of 0.1 mol/dm(3). The sample with this metal ion concentration had nanocrystalline ZnGa2O4 phosphor with an average size of about 80 nm. The emission spectra of ZnGa2O4 showed a broad self-activated blue emission band spanning over in the wide range of 300-600 nm with a peak wavelength of about 420 nm; this band showed a maximum intensity at a metal ion concentration of 0.1 mol/dm(3).