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41.
Embodied conversational agents (ECAs) are computer-generated, human-like characters that interact with human users in face-to-face conversations. ECA is a powerful tool for representing cultural differences and is suitable for interactive training or edutainment systems. This article presents preliminary results from the development of a culture-adaptive virtual tour guide agent for serving Japanese, Croatian, and general Western users by displaying appropriate verbal and non-verbal behaviors. It is being implemented in Generic ECA Framework, a modular framework for developing ECAs. Dividing the ECA functions into reusable and loosely coupled modules minimizes the effort required to implement additional behavior and facilitates incremental scale up of the system.  相似文献   
42.
BACKGROUND: Bioethanol is mostly produced from starchy parts of the corn grain kernel leaving significant amounts of valuable by‐products such as dried distillers' grains with solubles (DDGS) which can be used as a substitute for traditional feedstuff. The suitability of six maize hybrids from Serbia was investigated for bioethanol and DDGS production. The correlation between physical and chemical characteristics of the grain, bioethanol yield and quality of the corresponding DDGS was assessed. RESULTS: All hybrids had very different chemical composition and physical characteristics which could allow various applications. The highest bioethanol yield (94.5% of theoretical) and volumetric productivity (2.01 g l?1 h?1) were obtained with hybrid ZP 434 and the lowest with ZP 611k. Regarding chemical composition, all DDGS samples manifested good properties as feed components. Their protein content was higher compared to the kernel. In addition, the samples showed high digestibility and high mineral content, especially of calcium and phosphorus. CONCLUSION: A hybrid ZP 434 was selected as the most promising bioethanol producer. This property is attributed to the highest level of soft endosperm which is more susceptible to starch‐hydrolysing enzymes. A high yield potential per hectare makes it the best candidate for commercial bioethanol production. © 2012 Society of Chemical Industry  相似文献   
43.
We have compared the results of estimations of the total number of protein-coding genes in the Saccharomyces cerevisiae genome, which have been obtained by many laboratories since the yeast genome sequence was published in 1996. We propose that there are 5300-5400 genes in the genome. This makes the first estimation of the number of intronless ORFs longer than 100 codons, based on the features of the set of genes with phenotypes known in 1997 to be correct. This estimation assumed that the set of the first 2300 genes with known phenotypes was representative for the whole set of protein-coding genes in the genome. The same method used in this paper for the approximation of the total number of protein-coding sequences among more than 40 000 ORFs longer than 20 codons gives a result that is only slightly higher. This suggests that there are still some non-coding ORFs in the databases and a few dozen small ORFs, not yet annotated, which probably code for proteins.  相似文献   
44.
A versatile wavelet domain noise filtration technique for medical imaging   总被引:18,自引:0,他引:18  
In this paper, we propose a robust wavelet domain method for noise filtering in medical images. The proposed method adapts itself to various types of image noise as well as to the preference of the medical expert; a single parameter can be used to balance the preservation of (expert-dependent) relevant details against the degree of noise reduction. The algorithm exploits generally valid knowledge about the correlation of significant image features across the resolution scales to perform a preliminary coefficient classification. This preliminary coefficient classification is used to empirically estimate the statistical distributions of the coefficients that represent useful image features on the one hand and mainly noise on the other. The adaptation to the spatial context in the image is achieved by using a wavelet domain indicator of the local spatial activity. The proposed method is of low complexity, both in its implementation and execution time. The results demonstrate its usefulness for noise suppression in medical ultrasound and magnetic resonance imaging. In these applications, the proposed method clearly outperforms single-resolution spatially adaptive algorithms, in terms of quantitative performance measures as well as in terms of visual quality of the images.  相似文献   
45.
We present a methodology for managing outsourcing projects from the vendor's perspective, designed to maximize the value to both the vendor and its clients. The methodology is applicable across the outsourcing lifecycle, providing the capability to select and target new clients, manage the existing client portfolio and quantify the realized benefits to the client resulting from the outsourcing agreement. Specifically, we develop a statistical analysis framework to model client behavior at each stage of the outsourcing lifecycle, including: (1) a predictive model and tool for white space client targeting and selection—opportunity identification (2) a model and tool for client risk assessment and project portfolio management—client tracking, and (3) a systematic analysis of outsourcing results, impact analysis, to gain insights into potential benefits of IT outsourcing as a part of a successful management strategy. Our analysis is formulated in a logistic regression framework, modified to allow for non-linear input–output relationships, auxiliary variables, and small sample sizes. We provide examples to illustrate how the methodology has been successfully implemented for targeting, tracking, and assessing outsourcing clients within IBM global services division.Scope and purposeThe predominant literature on IT outsourcing often examines various aspects of vendor–client relationship, strategies for successful outsourcing from the client perspective, and key sources of risk to the client, generally ignoring the risk to the vendor. However, in the rapidly changing market, a significant share of risks and responsibilities falls on vendor, as outsourcing contracts are often renegotiated, providers replaced, or services brought back in house. With the transformation of outsourcing engagements, the risk on the vendor's side has increased substantially, driving the vendor's financial and business performance and eventually impacting the value delivery to the client. As a result, only well-ran vendor firms with robust processes and tools that allow identification and active management of risk at all stages of the outsourcing lifecycle are able to deliver value to the client. This paper presents a framework and methodology for managing a portfolio of outsourcing projects from the vendor's perspective, throughout the entire outsourcing lifecycle. We address three key stages of the outsourcing process: (1) opportunity identification and qualification (i.e. selection of the most likely new clients), (2) client portfolio risk management during engagement and delivery, and (3) quantification of benefits to the client throughout the life of the deal.  相似文献   
46.
In bacteria, the DsbA oxidoreductase is a crucial factor responsible for the introduction of disulfide bonds to extracytoplasmic proteins, which include important virulence factors. A lack of proper disulfide bonds frequently leads to instability and/or loss of protein function; therefore, improper disulfide bonding may lead to avirulent phenotypes. The importance of the DsbA function in phytopathogens has not been extensively studied yet. Dickeya solani is a bacterium from the Soft Rot Pectobacteriaceae family which is responsible for very high economic losses mainly in potato. In this work, we constructed a D. solani dsbA mutant and demonstrated that a lack of DsbA caused a loss of virulence. The mutant bacteria showed lower activities of secreted virulence determinants and were unable to develop disease symptoms in a potato plant. The SWATH-MS-based proteomic analysis revealed that the dsbA mutation led to multifaceted effects in the D. solani cells, including not only lower levels of secreted virulence factors, but also the induction of stress responses. Finally, the outer membrane barrier seemed to be disturbed by the mutation. Our results clearly demonstrate that the function played by the DsbA oxidoreductase is crucial for D. solani virulence, and a lack of DsbA significantly disturbs cellular physiology.  相似文献   
47.
This paper presents the results of studies of wall effects in commercial soap-based greases LT4-S2 and HUTPLEX EP-2, thickened with, respectively, lithium 12-hydroxystearate and overbased calcium sulfonate. The studies were conducted in the presence of five different materials: copper alloy C11000, bronze B476, EPDM rubber and PTFE and PU thermoplastics. The influence of the energy state of the surface layer of the adsorbents and temperature (ranging from ?20 to 60 °C) on the intensity of wall effects was investigated. Changes in the structural viscosity and shear stress in the boundary layer area in the greases and the soap-based thickener’s ability to adsorb on the surfaces of the adsorbents were determined by evaluating the rheological parameter plateau modulus.  相似文献   
48.
49.
A series of solution‐processable and strongly visible‐light absorbing polyplatinynes containing oligothienyl–fluorene ring hybrids were synthesized and characterized. These rigid‐rod organometallic materials are soluble in polar organic solvents and show intense absorptions in the visible spectral region, rendering them excellent candidates for bulk heterojunction polymer solar cells. The photovoltaic behavior depends significantly on the number of thienyl rings along the polymer chain, and some of these polymer solar cells show high power conversion efficiencies (PCEs) of up to 2.9% and a peak external quantum efficiency to 83% under AM1.5 simulated solar illumination. The effect of oligothienyl chain length on improving the polymer solar cell efficiency and on their optical and charge transport properties is elucidated in detail. At the same blend ratio of 1:5, the light‐harvesting capability and PCE increase markedly with increasing number of thienyl rings. The power dependencies of the solar cell parameters (including the short‐circuit current density, open‐circuit voltage, fill‐factor, and PCE) were also examined. The present work opens up an attractive avenue to developing conjugated metallopolymers with broad and strong solar energy absorptions and tunable solar cell efficiency and supports the potential of metalated conjugated polymers for efficient power generation.  相似文献   
50.
Three types of mesoporous molecular sieves (silicate MCM-41, niobosilicate NbMCM-41, and aluminosilicate AlMCM-41) were impregnated with alkali metal acetates. The textural stability of the samples was estimated on the basis of XRD measurements and nitrogen adsorption/desorption methods. The acidic–basic properties of the obtained materials were tested in the cyclization of acetonylacetone and studied by FTIR spectroscopy after adsorption of methylacetylene (propyne) and pyridine. Two types of chemical reactions between mesoporous matrix and alkali metal salt/oxide were observed: the reaction between alkali metal salt and silica/silicate and the reaction between basic oxide and silanol groups or Na+ cations. In the first one the alkali metal silicate formation decreases from Li to Cs species and leads to the destruction of the material. The second reaction places alkali metal cations in extra framework positions, which increases from Li to Cs species and is only observed in the case of AlMCM-41 and NbMCM-41 materials. As a result of the second reaction Lewis acidity is generated. The average effect of these two interactions leads to the volcanic curve for basicity of M/AlMCM-41 and M/NbMCM-41 with the maximum for K-samples. In contrast, basicity of M/MCM-41 systematically increases from Li to Cs form since the second type of interaction does not occur for these samples.  相似文献   
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