A Signed Array Multiplier with Bypassing Logic

A low power digital signed array multiplier based on a 2-dimensional (2-D) bypassing technique is proposed in this work. When the horizontally (row) or the vertically (column) operand is zero, the corresponding bypassing cells skip redundant signal transitions to avoid unnecessary calculation to reduce power dissipation. An 8×8 signed multiplier using the 2-D bypassing technique is implemented on silicon using a standard 0.18 μm CMOS process to verify power reduction performance. The power-delay product of the proposed 8×8 signed array multiplier is measured to be 31.74 pJ at 166 MHz, which is significantly reduced in comparison with prior works.     

Retracted: A study of a B2C supporting interface design system for the elderly

People are now living longer because of advances in medical science, resulting in the percentage of the elderly in the population increasing year by year. These older individuals cannot move about like youngsters do. Internet shopping could become one of the most important shopping channels for them. According to related domestic and foreign survey results, this is confirmed by the increased percentage of elderly Internet shoppers. A lot of consumers, however, are still not satisfied with their Internet shopping experiences. Many have had the experience of giving up before completing the purchasing procedure. The key factors included in such procedures are rather complex, and user interfaces are not necessarily well‐designed. Nowadays, most websites are still designed for the convenience of the seller instead of the consumers. Often consumers find that their interfaces are complex and hard to use and that they require a high mental workload. Based on the behavioral model of older Internet consumers and difficulties they have encountered, and after exploring the information provided by shopping websites and evaluating the status of their current interface design, this study proposes an example of a supporting interface design system (SIDS) for the elderly. The effects of the SIDS are verified experimentally. A total of 12 subjects participated in the experiment. The results showed that the SIDS could successfully reduce the time spent by the elderly subjects on inputting data during the shopping process and the number of repetitions and the time spent on searching for, examining, and comparing products. Furthermore, it was also helpful to reduce the mental workload caused by Internet shopping. © 2012 Wiley Periodicals, Inc.     

Threshold jumping and wrap-around scan techniques toward efficient tag identification in high density RFID systems

With the emergence of wireless RFID technologies, the problem of Anti-Collision has been arousing attention and instigated researchers to propose different heuristic algorithms for advancing RFID systems operated in more efficient manner. However, there still have challenges on enhancing the system throughput and stability due to the underlying technologies had faced different limitation in system performance when network density is high. In this paper, we present a Threshold Jumping (TJ) and a Wrap-Around Scan (WAS) techniques, which are query tree based approaches, aiming to coordinate simultaneous communications in high density RFID environments, to speedup tag identification, to increase the overall read rate and to improve system throughput in large-scale RFID systems. The main idea of the Threshold Jumping is to limit the number of collisions. When the number of collisions exceeds a predefined threshold, it reveals that tag density in RF field is too high. To avoid unnecessary enquiry messages, the prefix matching will be moved to next level of the query tree, alleviating the collision problems. The method of setting frequency bound indeed improves the efficiency in high density and randomly deployed RFID systems. However, in irregular or imbalanced RFID networks, inefficient situation may happen. The problem is that the prefix matching is performed in single direction level-order scheme, which may cause an imbalance query tree on which the right sub-tree always not been examined if the identification process goes to next level before scan the right sub-tree due to threshold jumping. By scanning the query tree from right to left in alternative levels, i.e., wrap-around, this flaw cold be ameliorated. To evaluate the performance of proposed techniques, we have implemented the TJ and the WAS method along with the query tree protocol. The simulation results show that the proposed techniques provide superior performance in high density environments. It is shown that the TJ and WAS are effective in terms of increasing system throughput and minimizing identification delay.     

Microbioreactor designed for integration with piezoelectric transducers for cellular diagnostics

This article reports a perfusion-based microbioreactor that can be integrated with a thin-film piezoelectric transducer array for rapid disease diagnosis, such as identifications of cancer cells and infection induced cell abnormality. By using the gap between suspended transducers as the high-aspect ratio barriers to establish high flow resistance into the culture chamber, we have verified that diffusion dominated the main transport mechanisms in the culture chamber. The fluid flow was successfully suppressed under 0.03, 0.3, and 3.0 μl/min volume flow rates, and a very low shear flow region was achieved on the transducer surfaces. This design offers minimal influences of mechanical forces on cellular detection and cells cultured on the surface of transducers. Finite element simulation showed that the shear stress on transducer surface could be maintained lower than milli-Pascal range. Detailed design, simulation results and experimental verifications of the microbioreactor are discussed.     

Bayesian decision theory for support vector machines: Imbalance measurement and feature optimization

Classification approaches usually present the poor generalization performance with an apparent class imbalance problem. Surely, a measures of the quality of the possible models reflected the remaining uncertainty in the class imbalance on learning. The purpose of our learning method is to lead an attractive pragmatic expansion scheme of the Bayesian approach to assess how well it is aligned with the class imbalance problem. Thus, we propose a method with a model assessment of the interplay between various classification decisions using probability, corresponding decision costs, and quadratic program of optimal margin classifier called: Bayesian Support Vector Machines (BSVMs) learning strategy. In the framework, we did modify in the objects and conditions of primal problem to reproduce an appropriate learning rule for an observation sample. The experiments on several existing data sets showed that BSVMs may appropriately capture the true relationship between the inputs and outputs by experimental evidence.     

A thin multi-ring negative liquid crystal lens enabled by high-�� dielectric material

This study is dedicated to design an liquid crystal (LC) negative lens with unequal width electrodes, which is made for a camera lens and with the aim to replace conventional negative lenses. The structure of the LC negative lens is symmetric for producing a symmetrical electric field. The unequal widths are adopted and determined inversely proportional to the slopes of the desired applied voltages at varied radial positions. There are four ring electrodes in the lens and the associated with applied different voltages. In addition, the performance of the designed LC lens is verified by the software DIMOS.2D. The special structure and the material are used to realize the designed LC lens. Moreover, a new fabrication process in the wafer level to bury bus lines is developed in order to smooth the generated electric field distribution. In addition, a high-?? dielectric layer is coated between the electrodes and the LC layer for minimizing required applied voltage. Finally, differential effects of the LC lens structure with high-?? and without high-?? are discussed based on simulation results.     

External stimulus-responsive biomaterials designed for the culture and differentiation of ES,iPS, and adult stem cells

The physical and chemical characteristics of biomaterial surface and hydrogels can be altered by external stimuli, such as light irradiation, temperature changes, pH shifts, shear stress forces, electrical forces, and the addition of small chemical molecules. Such external stimulus-responsive biomaterials represent promising candidates that have been developed for the culture and differentiation of embryonic stem (ES) cells, induced pluripotent stem (iPS) cells, and adult stem cells. Biomaterials that are designed to respond in a reversible manner to specific external signals can be formed on micropatterned or non-micropatterned surface, in hydrogels, or on microcarriers. Stem cells and the cells differentiated from them into specific tissue lineages can be cultured and/or differentiated on dishes with immobilized external stimulus-responsive polymers. Cells can be detached from these dishes without using an enzymatic digestion method or a mechanical method when the appropriate external stimulus is generated on the surface. This review discusses the polymers and polymeric designs employed to produce surface and hydrogels for stem cell culture, differentiation, and/or cell detachment using various external stimuli.     

High Cytoplasmic Expression of Krüppel-like Factor 4 Is an Independent Prognostic Factor of Better Survival in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality in the world. Hepatocarcinogenesis is complex, with an extraordinary molecular heterogeneity. Krüppel-like factor 4 (KLF4) plays an important role in cell proliferation and differentiation, and it can function as a tumor suppressor or an oncoprotein, depending on tissue type. The role of KLF4 in HCC remains controversial. The aim of this study was to explore the clinical significance of KLF4 expression in HCC. The study included 205 patients with surgical resection. We performed immunostaining for KLF4 and Ki-67 to investigate the correlations of the clinicopathological parameters of HCC and to examine the proliferative index. KLF4 staining was observed in the cytoplasm of non-tumorous hepatocytes and tumor cells. We subdivided the immunohistological staining results for KLF4 into low expression (Staining 0 and 1+) and high expression (Staining 2+ and 3+) subgroups. The expression of KLF4 was significantly correlated with tumor differentiation (p = 0.001). The Ki-67 proliferative index was significantly lower in well-differentiated HCCs (0.781% ± 1.02% vs. 2.16% ± 3.14%, p = 0.012), but not significantly different between low-KLF4 expression and high-KLF4 expression (1.87% ± 2.93% vs. 2.51% ± 3.28%, p = 0.32). Kaplan–Meier analysis showed that a high expression of KLF4 was significantly correlated with a longer disease-specific survival (p = 0.019). Univariate and multivariate analyses showed that high KLF4 expression was an independent predictor of a better disease-specific survival (p = 0.017; hazard ratio = 0.398; 95% confidence interval: 0.19–0.85). High cytoplasmic expression of KLF4 was associated with better disease-specific survival and was an independently favorable prognostic factor in hepatocellular carcinoma. These promising results suggest that KLF4 may play an anti-oncogenic role in hepatocarcinogenesis.