A design of linear-phased IIR Nyquist filters

This paper discusses a new method of designing linear-phased IIR Nyquist filters with zero intersymbol interference. The filters designed by this method possess linear-phase characteristics and are lower in order than other Nyquist filters designed by existing methods. Expressions are derived for zero-phased IIR Nyquist filters and efficient design methods are examined for them. The opted design method is based on an iteration process, and in each iteration step a modified version of the Remez exchange algorithm is used. In addition, the implementation of the designed zero-phased IIR filters is considered. Finally, the proposed design method is demonstrated through various design examples     

A 5.6-mW 1-Gb/s/pair pulsed signaling transceiver for a fully AC coupled bus

This paper describes a low-power synchronous pulsed signaling scheme on a fully AC coupled multidrop bus for board-level chip-to-chip communications. The proposed differential pulsed signaling transceiver achieves a data rate of 1 Gb/s/pair over a 10-cm FR4 printed circuit board, which dissipates only 2.9 mW (2.9 pJ/bit) for the driver and channel termination and 2.7 mW for the receiver pre-amplifier at 500 MHz. The fully AC coupled multipoint bus topology with high signal integrity is proposed that minimizes the effect of inter-symbol interference (ISI) and achieves a 3 dB corner frequency of 3.2 GHz for an 8-drop PCB trace. The prototype transceiver chip is implemented in a 0.10-/spl mu/m 1.8-V CMOS DRAM technology and packaged in a WBGA. It occupies an active area of 330/spl times/85 /spl mu/m/sup 2/.     

Effective representation using ICA for face recognition robust to local distortion and partial occlusion

The performance of face recognition methods using subspace projection is directly related to the characteristics of their basis images, especially in the cases of local distortion or partial occlusion. In order for a subspace projection method to be robust to local distortion and partial occlusion, the basis images generated by the method should exhibit a part-based local representation. We propose an effective part-based local representation method named locally salient ICA (LS-ICA) method for face recognition that is robust to local distortion and partial occlusion. The LS-ICA method only employs locally salient information from important facial parts in order to maximize the benefit of applying the idea of "recognition by parts". It creates part-based local basis images by imposing additional localization constraint in the process of computing ICA architecture I basis images. We have contrasted the LS-ICA method with other part-based representations such as LNMF (localized nonnegative matrix factorization) and LFA (local feature analysis). Experimental results show that the LS-ICA method performs better than PCA, ICA architecture I, ICA architecture 11, LFA, and LNMF methods, especially in the cases of partial occlusions and local distortions.     

Direct Synthesis of a Self‐Assembled WSe2/MoS2 Heterostructure Array and its Optoelectrical Properties

Functional van der Waals heterojunctions of transition metal dichalcogenides are emerging as a potential candidate for the basis of next‐generation logic devices and optoelectronics. However, the complexity of synthesis processes so far has delayed the successful integration of the heterostructure device array within a large scale, which is necessary for practical applications. Here, a direct synthesis method is introduced to fabricate an array of self‐assembled WSe₂/MoS₂ heterostructures through facile solution‐based directional precipitation. By manipulating the internal convection flow (i.e., Marangoni flow) of the solution, the WSe₂ wires are selectively stacked over the MoS₂ wires at a specific angle, which enables the formation of parallel‐ and cross‐aligned heterostructures. The realized WSe₂/MoS₂‐based p–n heterojunction shows not only high rectification (ideality factor: 1.18) but also promising optoelectrical properties with a high responsivity of 5.39 A W^?1 and response speed of 16 µs. As a feasible application, a WSe₂/MoS₂‐based photodiode array (10 × 10) is demonstrated, which proves that the photosensing system can detect the position and intensity of an external light source. The solution‐based growth of hierarchical structures with various alignments could offer a method for the further development of large‐area electronic and optoelectronic applications.     

Life cycle environmental loads and economic efficiencies of apartment buildings built with plaster board drywall

Due to the ease of remodeling apartment buildings, as well as the increased lifespans and performances required of apartment buildings, the demand for new plaster board drywall materials with outstanding flexibility is growing, and the importance of assessing the associated environmental load is increasing. This study evaluates the CO₂ generated during the life cycle of a building (LCCO₂) and its economic efficiency to assess the environmental loads and costs of buildings that use plaster board drywall.A typical concrete bearing wall structure for an apartment building was defined as case 1, and comparisons were performed with alternative samples (cases 2, 3, and 4) containing different ratios of plaster board drywall on top of case 1. The structural safety of each sample building was considered along with the legal incentives according to the use of variable type wall. In addition, life cycle assessments of both CO₂ and economic efficiency were conducted according to stage, including the construction stage, operation/maintenance stage, and demolition/waste stage. Data including quantity of construction material, amount of energy usage, repair rate, and repair period (all of which are required during each stage of assessment) were utilized for the assessment of both CO₂ and economic efficiency.As a result, in flat-type structures, the CO₂ reduction rates of cases 2, 3, and 4 compared to case 1 were 1.0%, 4.5%, and 5.4%, respectively. In the assessment of cost, the reduction rates compared to case 1 were −0.01%, 5.8%, and 6.0%, respectively. Also, in the tower-type structure, the CO₂ reduction rates of cases 2, 3, and 4 compared to case 1 were 1.3%, 4.9%, and 5.5%, respectively. In cost assessment, the reduction rates compared to case 1 were −1.1%, 3.3%, and 3.5%, respectively.     

Factors influencing rumen microbial growth rates and yields: effect of amino acid additions to a purified diet with nitrogen from urea.

Effects of isonitrogenous urea and amino acid additions upon microbial growth in rumen contents from a cow fed a purified diet in which urea was the sole nitrogen source were studied. Incorporation of amino acids into microbial cells, volatile fatty acids, and carbon dioxide was estimated. Rates of microbial growth, volatile fatty acid production, and effects of amino acids upon microbial nitrogen yields were highest right after feeding and decreased with time after feeding. Microbial growth and amounts of amino acids incorporated into microbial cells, volatile fatty acids and carbon dioxide were related closely to quantity of starch remaining in the rumen. High amounts of starch increased microbial protein synthesis from carbon-14 labeled amino acids and reduced amounts of amino acid fermentation. Estimated microbial protein yields per day were 326.0, 444.4, 497.3, and 527.3 g when 0, 15, 30, and 45 mg amino acid nitrogen replaced urea nitrogen during incubation. Respective values for microbial cells per mole estimated adenosine triphosphate were 15.2, 19.2, 21.0, and 24.5. Microbial cell yields per kg carbohydrate digested were 139.0, 189.5, 212.0, and 224.8 g for 0, 15, 30, and 45 mg amino acid nitrogen. Addition of small amounts of amino acids to a diet containing urea as the sole nitrogen source improved considerably rumen microbial protein yields.     

Effects of medium high pressure treatments on protease activity

The ability of Lactobacillus manihotivorans LMG 18010 to produce l(+)-lactic acid from a high concentration of starch by direct fermentation was investigated. To improve the production of lactic acid from a highly concentrated starch, fed-batch cultures were carried out with different feeding strategies to reduce substrate inhibition. The highest lactic acid production was 71.4 g/L, which was obtained by intermittent feeding of concentrated starch media containing nitrogen sources. After 5 days of fermentation, about 87% of the substrate was consumed with a volumetric productivity of 0.6 g/L·h which is 1.8 times higher than that obtained from batch fermentation. This result clearly shows that intermittant feeding of a highly concentrated substrate solution during fermentation is an efficient way of eliminating substrate inhibition.     

A CAWL handler for context-aware composite workflow services

In distributed computing environment,workflow technologies have been continuously developed.Recently,there is an attempt to apply these technologies to context-aware services in ubiquitous computing environment.The middleware,which offers services in such environments,should support the automation services suited for the user using various types of situational information around the user.In this paper,based on context-aware workflow language （CAWL）,we propose a CAWL based composite workflow handler for supporting composite workflow services,which can integrate more than two service flows and handle them.The test results shows that the proposed CAWL handler can provide the user with the composite workflow services to cope with various demands on a basis of a scenario document founded on CAWL.     

Significant Enhancement of the Dielectric Constant through the Doping of CeO2 into HfO2 by Atomic Layer Deposition

Films of CeO₂ were deposited by atomic layer deposition (ALD) using a Ce(mmp)₄ [mmp = 1‐methoxy‐2‐methyl‐2‐propanolate] precursor and H₂O reactant. The growth characteristics and film properties of ALD CeO₂ were investigated. The ALD CeO₂ process produced highly pure, stoichiometric films with polycrystalline cubic phases. Using the ALD CeO₂ process, the effects of Ce doping into an HfO₂ gate dielectric were systematically investigated. Regardless of Ce/(Ce + Hf) composition, all ALD Ce_xHf_1?xO₂ films exhibited constant growth rates of approximately 1.3 Å/cycle, which is essentially identical to the ALD HfO₂ growth rates. After high‐temperature vacuum annealing at 900°C, it was verified, based on X‐ray diffraction and high‐resolution cross‐sectional transmission electron microscopy results, that all samples with various Ce/(Ce + Hf) compositions were transformed from nanocrystalline to stabilized cubic or tetragonal HfO₂ phases. In addition, the dielectric constant of the Ce_xHf_1?xO₂ films significantly increased, depending on the Ce doping content. The maximum dielectric constant value was found to be nearly 39 for the Ce/(Ce + Hf) concentration of ~11%.