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Utility mining considers high-utility itemsets as useful by combining item quantities and item benefits. Its mining results do not, however, include the quantity information such as large amounts or small amounts. Fuzzy utility mining is thus proposed to fuzzify the results of utility mining and obtain linguistic high-utility itemsets. However, fuzzy utility measurement is not fair to evaluate itemsets because the fuzzy utility value of an itemset in a transaction may be higher than those of its subsets. In the past, we defined the fuzzy average utility mining to solve the above problem and proposed a two-phase method to solve the fuzzy average-utility mining problem and find high fuzzy average-utility itemsets. However, its execution is slow. In this paper, an efficient algorithm is proposed, which uses a tree structure to solve fuzzy average-utility mining. The proposed tree-structure method is compared with the previous two-phase approach. Experimental evaluation shows that the efficiency of the proposed method is better than that of the two-phase algorithm in execution time and numbers of candidates.

We present the first space flight use of the electrostatically actuated Next Generation MicroShutter Array systems (NGMSA) as multiple celestial object selectors developed for NASA space telescope missions at the NASA Goddard Space Flight Center. The NGMSA assembly was installed in the Next Generation Far-ultraviolet Off Rowland-circle Telescope for Imaging and Spectroscopy (NG-FORTIS) and successfully launched recently from the White Sands Missile Range in October 2019. We started to investigate this electrostatic NGMSA technology at the late stages of James Webb Space Telescope (JWST) in 2009 to strategically align with requirements of larger field of view for future telescopes in space. The NGMSA in NG-FORTIS is a 128 X 64 programable 2-D addressing microfabricated shutter array while the current NGMSA system under development is a 736 X 384 large format. The new microshutter array (MSA) features several unique designs aiming at performance improvements: electrostatic actuation, thinned microshutters, better electrical wall insulation and anti-stiction surface coating. To ensure reliable operation in the space environment, NGMSA systems have passed a series of critical environment tests including acoustic, random vibration, life cycle of operation, thermal cycling, and optical contrast tests. The successful launch of the NG-FORTIS sounding rocket equipped with NGMSA demonstrates our NGMSA technology have achieved the highest NASA Technical Readiness Level 9 for sounding rocket space applications.

We present here an insulator based dielectrophoresis (iDEP) chip capable of single cell trapping and encapsulation with high efficiency. The proposed microfluidic chip can be easily tuned for trapping various size of cells. This microfluidic device is fabricated using a technique called lift off polydimethyl siloxane (PDMS). The fabrication technique eliminates the difficulty in handling a thin membrane with a large number of holes. The device also has advantage of generating droplets of very small volume. We have demonstrated the working of chip using THP1 cells. We have achieved efficiency of 90% for single cell encapsulation.

Burst packet loss problem is a common phenomenon over wired and wireless networks. Forward error correction (FEC) mechanism generally aims to recover the lost packets during transmission, but the performance of FEC degrades in the presence of burst packet loss. The traditional FEC interleaving mechanism sequentially encodes FEC packets and reorders the packet transmission sequence in such a way that the burst loss effect can be mitigated with the cost of increased delay. This paper presents a novel FEC interleaving mechanism to reduce the long interleaving delay while maintaining the performance enhancement provided by the interleaving technique. Specifically, the proposed mechanism, namely interleaving-coding-sequential-transmission (ICST) FEC, rearranges the sequence of FEC coding in an interleaved manner, and transmits packets sequentially in accordance with their generation order in the application.

This paper demonstrates the design of a radio frequency (RF) class A power amplifiers for WiMAX application using TSMC 0.18µm CMOS technology. A novel two-stage cascode common-source amplifier and a load-pull output matched power amplifier are designed for the WiMAX application of 2.5GHz transmitting frequency. The designed power amplifier exhibits 19.8dBm of 1-dB compression point, 24.1dBm of output power, 35% power-added-efficiency (PAE), and 23.3dB of power gain under 3.3V and 1.8V supply voltages. The power consumption is about 827.34mW. A small chip size of 0.81×0.65 mm2 is achieved with all matching networks.

The fully scalable motion model (SMM) is proposed for scalable video codec by taking advantage of motion information scalability. In previous work, SMM has been improved to support hierarchical B frame and bidirectional or multidirectional motion estimation. It yields better results comparing to method using unidirectional motion estimation. However, the process of bidirectional or multidirectional rate distortion optimization motion estimation is very complex and is the most time-consuming task in the encoding process. We present several algorithms to reduce its complexity and show corresponding simulation to compare their performance.

Motion scalability is designed to improve the coding efficiency of a scalable video coding framework, especially in the medium to low range of decoding bit rates or spatial resolutions. In order to fully benefit from the superiority of motion scalability, a rate-distortion optimized bitstream extractor, which determines the optimal motion quality layer for each decoding scenario, is required. In this paper, the determination process first starts off with a brute force searching algorithm. Although guaranteed by the optimal performance within the search domain, it has high computational complexity. Two properties, i.e. the monotonically non-decreasing property and the unimodal property, are then derived to accurately describe the rate-distortion behavior of motion scalability. Based on these two properties, modified searching algorithms are proposed to reduce the complexity by a factor up to 5.

A multi-stage low-noise amplifier (LNA) with LC-tank load to extend the bandwidth is designed for ultra-wideband (UWB) wireless receiver. The design consists of three LC-tank cascode amplifier and one output buffer and is implemented in 0.18um RF CMOS process. The trade off on noise figure and chip area in low-noise amplifier design is discussed. The two LNA (LC and Res) gives 14.5 dB gain; 7.2 GHz and 7.0 GHz 3 dB bandwidth (3.1-10.3 GHz and 3.1- 10.1 GHz) while consuming 22.8 mW and 23.8 mW through a 1.5 V supply. Over the 3.1 GHz - 10.3 GHz and 3.1 GHz- 10.1 GHz frequency band, a minimum noise figure of 2.6 dB and 6.3 dB and input return loss lower than -8.8 dB and - 6.8 dB have been achieved.

A current reused low-noise amplifier (LNA) with gain compensated to extend the bandwidth which is designed for ultra-wideband (UWB) wireless receiver. The design consists of two cascode common-source amplifier and an output buffer which is implemented in 0.18 um RF CMOS process. The LNA gives 13.1 dB gain; 9.1 GHz 3 dB bandwidth (3.1-12.2 GHz) while consuming 13.9 mW through a 1.8 V supply. Over the 3.1 GHz - 10.6 GHz frequency band, a minimum noise figure of 2.7 dB and input return loss lower than -8.7 dB have been achieved.

In this paper a CMOS dual-wideband low-noise amplifier (LNA) is designed for ultra-wideband (UWB) wireless receiver radio system. The design consists of a wideband input impedance matching network, two stage cascode amplifiers with shunt-peaked load, two 2nd-order notch filters and an output buffer for measurement purpose. It is simulated in TSMC 0.18 mum standard RF CMOS process. The LNA gives 13.1 dB maximum power gain between 3.0 GHz-4.9 GHz and 15.5 dB maximum power gain between 6.2 GHz-10.2 GHz while consuming 21.9 mW through a 1.8 V supply. Over the 3.1 GHz-4.9 GHz frequency band and the 6.2 GHz-10.2 GHz, a minimum noise figure is 2.5 dB and 2.8 dB. Input return loss lower than -6.4dB in all bandwidth have been achieved.

Motion information scalability is an important requirement for a fully scalable video codec, especially for decoding scenarios of low bit rate or small image size. So far, several scalable coding techniques on motion information have been proposed, including progressive motion vector precision coding and motion vector field layered coding. However, it is still vague on the required functionalities of motion scalability and how it collaborates flawlessly with other scalabilities, such as spatial, temporal, and quality, in a scalable video codec. In this paper, we first define the functionalities required for motion scalability. Based on these requirements, a fully scalable motion model is proposed along with tailored encoding techniques to minimize the coding overhead of scalability. Moreover, the associated rate distortion optimized motion estimation algorithm will be provided to achieve better efficiency throughout various decoding scenarios. Simulation results will be presented to verify the superiorities of proposed scalable motion model over nonscalable ones.

This paper presents a common gate low-power low noise amplifier (LNA) for DS-UWB low-band and MB-OFDM group-A ultra-wideband radio system. The LNA is designed and implemented in 0.18 mum RF CMOS process. Simulation results show that power gain of 15.4 dB, input and output matching lower than -10.6 dB and -13.3 dB, and a minimum NF of 3.8 dB can be achieved, while the power consumption is only 3.24 mW through 1.8 V power supply

We propose a motion vector field (MVF) scaling algorithm which includes both up-sampling and down-sampling operations. Through this model, it is possible to obtain all the MVF information required for different spatial resolutions in scalable video coding (SVC) efficiently from a pre-specified spatial layer. There's no need to go through all the computationally intensive motion estimation (ME) operations in order to gather those information. This scheme, of course, saves a huge amount of computational power since ME and rate distortion optimization (RDO) typically are the most time consuming tasks in a generic video codec. In video broadcasting application, the proposed algorithm could provide even better coding efficiency than conventional methods in the rate distortion sense.

Most of the existing methods designed to implement fractional interpolation and decimation are limited by rational scaling factors such as L/M, where L and M are positive integers. The general procedure is usually done with up-sampling by L first, and then followed by down-sampling by M. This scheme, however, requires two steps to fulfill and is not capable in dealing with irrational scaling factors, which can not be represented by L/M. In this paper, we propose a new method to solve the above two difficulties by a single step. Furthermore, a perfect reconstruction filter bank is derived using this new method and the experimental results are presented.

In this paper, we propose a new method to realize an irrational scaling of a 2D digital signal/image. This method is suitable for any scaling matrices with real entries, including irrational numbers. Based on this algorithm, a new structure of a 2D four-channel non-uniform perfect reconstruction filter bank is derived. Through the proposed structure, it is now possible to segment the 2D frequency components of a 2D digital signal/image arbitrarily through a careful design of the scaling matrix while still preserving the PR property. Therefore, we can find many applications such as image compression and communication using this structure. The experimental results are presented at the end of this paper.

An efficient method for computing a length-N Discrete Cosine Transform (DCT) from three consecutive length-N/3 DCTs is proposed. This method differs from previous ones in that it reduces considerable 31-38% arithmetic operations and uses only length-N/3 DCTs instead of length-N DCTs. We also find its great applications in fractional scaling of a block DCT-based image by the factor of 1/2/sup /spl alpha//3/sup /spl beta//. This would be very useful in high-definition television (HDTV) standard, whose display size is usually 16:9. The comparison with conventional methods is provided.