gebhart/patrepeval huggingface dataset:
Evaluation of human-robot arm movement imitation (2011)

Robot skill learning by imitation is an intuitive approach to learn robot skills from the observation of human behaviors. However, due to the discrepancy of mechanism between humans and robots such as the type of joint and the number of degree of freedom (DOF), a robot may not be able to imitate a human's movements faithfully. For a robot arm, the major problem is caused by the lack of a degree of freedom in the shoulder compared to a human arm. In this paper, we develop a similarity metric to evaluate how faithfully a robot arm imitates a human's arm movements. This metric is derived by utilizing the sequence-independent joint angle representation for both human and robot arms because it represents their postures more directly than the sequence-dependent Euler joint angle representation. In addition, the derived metric is formulated with the spatial relationship between human and robot arm postures instead of the Frobenius norm of the difference matrix between human and robot transformation matrices. To investigate the joint angles of the sequence-independent joint angle representation for a human arm, we adopt the particle-swarm optimization (PSO) to numerically derive them from human demonstration data. Computer simulations and experimental work were conducted to validate the proposed approach on a robot arm with two degrees of freedom in the shoulder and a DOF in the elbow.
Preparation and characterization of poly(ethylene oxide)/lithium montmorillonite composites (2012)

Poly(ethylene oxide)/lithium montmorillonite (PEO/L iMMT) composites were prepared by mixing and ultrasonication PEO and LiMMT in water. Characterization of PEO/LiMMT composites was performed by differential scanning c(DSC), Fourier transform infrared spectroscopy (FT-IR) and non-isothermal th ermogravimetry (TGA). DSC and TGA reveal that higher loadings of LiMMT significantly influence the crystallinity, melting temperatures and thermal stability of PEO, respecti vely. Glass transition temperatures of PEO do not change with addition of LiMMT. FT-IR ana lysis shows that the helical structure of PEO chains is distorted in PEO/LiMMT composites. Changes of activation energy in composites compared to pure PEO indicate possible c hanges in the mechanism of the nonisothermal degradation of PEO due to addition of Li MMT.
Aroma‐active compounds of Beijing roast duck (2009)

Abstract The aroma‐active compounds of Beijing roast duck were investigated by using aroma extract dilution analysis (AEDA), dynamic headspace dilution analysis (DHDA), gas chromatography–olfactometry–mass spectrometry (GC–O–MS) and odour activity values (OAVs; ratio of concentration to odour threshold). The following volatile components are the predominant odorants of Beijing roast duck: 3‐methylbutanal, hexanal, dimethyl trisulphide, methional, 2‐methylbutanal, octanal, heptanal, 2‐methyl‐3‐furanthiol, 2‐furfurylthiol, 2‐ethyl‐3,5‐dimethylpyrazine, ( E , E )‐2,4‐nonadienal, 1‐octen‐3‐ol, nonanal, decanal, ( E )‐2‐decenal, ( E , E )‐2,4‐decadienal, ( E )‐2‐nonenal, ( E , Z )‐2,6‐nonadienal, ( E , E )‐2,4‐octadienal (fatty, fried), etc. Due to abundant flavour precursors of Beijing crammed duck (raw material of Beijing roast duck), such as amino acids, esters, vitamins and carbohydrates, and the special process (e.g. roasting, drying, etc.), the identified compounds above were likely derived from different kinds of reactions, such as degradation of fatty acids and amino acids, Maillard/Strecker and other associated reactions, which were considered to account for the typical aroma of Beijing roast duck. Copyright © 2009 John Wiley & Sons, Ltd.
Early Events in the Pathogenesis of Avian Salmonellosis (1999)

Salmonellae are gastrointestinal pathogens of man and animals. However, strains that are host-specific avian pathogens are often avirulent in mammals, and those which are nonspecific are commensal in poultry. The objective of this study was to determine whether host specificity was exhibited by bacterial abilities to invade epithelial cells or resist leukocyte killing. In this study, leukocytes isolated from humans and chickens were used to kill Salmonella in vitro. Both Salmonella pullorum, an avian-specific serotype, and Salmonella typhimurium, a broad-host-range serotype, were sensitive to killing by polymorphonuclear leukocytes isolated from both species. Both serotypes replicated in cells of the MQ-NCSU avian-macrophage cell line. In contrast, S. pullorum was noninvasive for cultured epithelial Henle 407, chick kidney, chick ovary, and budgerigar abdominal tumor cells. In the bird challenge, however, S. typhimurium rapidly caused inflammation of the intestinal mucosa, but S. pullorum preferentially targeted the bursa of Fabricius prior to eliciting intestinal inflammation. Salmonella serotypes which cause typhoid fever in mice have been shown to target the gut-associated lymphoid tissue. Observations from this study show that S. pullorum initiated a route of infection in chicks comparable to the route it takes in cases of enteric fever.
Plaque Assay for Titration of Bovine Enteric Coronavirus (1981)

The plaquing ability of two isolates of bovine enteric coronavirus (BECV) was studied in HRT18 (human rectal adenocarcinoma) cell monolayers. Both isolates were able to induce plaque formation within 2 to 3 days; plaques appeared as round opalescent areas which remained colourless after neutral red or crystal violet staining. A good correlation was found between the titres as determined either by counting the plaques that were visible to the naked eye before and after neutral red staining, or by enumerating fluorescence or haemadsorption foci.
Diesel Engine Exhaust Emissions Modelling Using Artificial Neural Networks (1999)

<div class="htmlview paragraph">This work deals with Diesel engine exhaust emissions modelling. Although, the combustion process in internal combustion engine is very complex, the formation of products can then be predicted in order to control automotive polluting emissions.</div> <div class="htmlview paragraph">Firstly, we have defined a neural network structure based on the determination of time delays, input and output orders, and finally number of hidden layer neurons.</div> <div class="htmlview paragraph">Secondly, the proposed model has been applied on Diesel engine process. An Artificial neural networks (ANN) describing the prediction of exhaust emissions through its parameters is given</div>
On the implementation of software-only videoconferencing codec on PC (2002)

Intensive recent progress in computer technologies has stimulated new solutions for transmission of audio and video information in digital form, The transmission of digital video and audio signals through channels of restricted capacity, such as switched public telephone lines, mobile radio systems, local computer networks, Internet and satellite telecommunications attract a constantly growing interest. The bit rate in such lines available for transmission of audio and video information is limited dependent upon particular application in the range from 30 to 512 Kbit/s. In spite of the low bit rate digital coding itself requires significant computational resources and implies severe limitations on the performance of the real-time encoder. It should be also taken into account that for channels with low bit rate a codec must implement compression algorithms allowing us to achieve a large compression ratio and acceptable quality. Necessary compression ratios can be achieved only by means of intraframe coding as well as interframe motion compensation.
Nonsphericity of Bearing Geometry and Lubrication in Hip Joint Implants (2009)

A general elastohydrodynamic lubrication model was developed to consider the nonsphericity of the bearing geometry in hip joint implants, both under the steady and transient conditions. The articulation between the femoral head and the acetabular cup was represented by a nominal ball-in-socket configuration. The nonsphericity was introduced on the acetabular cup and femoral head bearing surfaces in the form of an ellipsoidal surface represented by variations of the radii of curvature given by the three semi-axis lengths of the ellipsoid with regard to a nominal spherical surface. An appropriate spherical coordinate system and solution domain discretization were used to facilitate the numerical simulations. Both the equivalent discrete spherical convolution model and the corresponding spherical fast Fourier transform technique were used to evaluate the elastic deformation of either the spherical or nonspherical bearing surfaces. A fixed-tracked method was also developed to simulate the complex morphology introduced by moving the interface of the nonspherical bearing surfaces. The general methodology for the nonspherical bearing was first applied to investigate the steady-state elastohydrodynamic lubrication of an ellipsoidal cup articulating against a spherical head in a typical metal-on-metal hip joint implant. Subsequently, the problem of an ellipsoidal head articulating against a spherical cup was considered under the transient conditions. The significance of nonsphericity of bearing geometry in hip joint implants due to manufacturing, designing, and wear was discussed. The results obtained showed that the effect of a nonspherical bearing surface geometry on elastohydrodynamic lubrication was dependent on the orientation, the magnitude, and the deviation direction of the nonsphericity. A well-controlled nonsphericity was seen to be beneficial for improving the lubrication.
Generation of silicon nanoparticles via femtosecond laser ablation in vacuum (2004)

We demonstrate that femtosecond laser ablation of silicon targets in vacuum is a viable route to the generation and deposition of nanoparticles with radii of ≈5–10 nm. The nanoparticles dynamics during expansion has been analyzed through their structureless continuum optical emission, while atoms and ions, also present in the plume, have been identified by their characteristic emission lines. Atomic force microscopy analysis of the material deposited at room temperature has allowed the characterization of the nanoparticles size distribution. Taking into account the emissivity of small particles we show that the continuum emission is a blackbody-like radiation from the nanoparticles. Our results suggest that nanoclusters are generated as a result of relaxation processes of the extreme material state reached by the irradiated target surface, in agreement with recently published theoretical studies.
Novel method for the synthesis of isomerically pure vinyl halides from alkynes via the hydroalumination reaction (1967)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNovel method for the synthesis of isomerically pure vinyl halides from alkynes via the hydroalumination reactionGeorge. Zweifel and Charles C. WhitneyCite this: J. Am. Chem. Soc. 1967, 89, 11, 2753–2754Publication Date (Print):May 1, 1967Publication History Published online1 May 2002Published inissue 1 May 1967https://pubs.acs.org/doi/10.1021/ja00987a054https://doi.org/10.1021/ja00987a054research-articleACS PublicationsRequest reuse permissionsArticle Views1618Altmetric-Citations157LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
A Distributed Security Mechanism for Resource-Constrained IoT Devices (2016)

Internet of Things (IoT) devices have developed to comprise embedded systems and sensors with the ability to connect, collect, and transmit data over the Internet. Although solutions to secure IoT systems exist, Class-0 IoT devices with insufficient resources to support such solutions are considered a resource constrained in terms of secure communication. This paper provides a distributed security mechanism that targets Class-0 IoT devices. The research goal is to secure the entire data path in two segments, device-to-gateway and gateway-to-server data communications. The main concern in the provided solution is that lighter security operations with minimal resource requirements are performed in the IoT device, while heavier tasks are performed in the gateway side. The proposed mechanism utilizes a symmetric encryption for data objects combined with the native wireless security to offer a layered security technique between the device and the gateway. In the offered solution, the IoT gateways provide additional protection by securing data using Transport Layer Security (TLS). Real-time experimental evaluations have demonstrated the applicability of the proposed mechanism pertaining to the security assurance and the consumed resources of the target Class-0 IoT devices.
Use of reflected light for low data rate upstream signalling in a single mode passive optical network (1990)

The paper assesses the feasibility of using reflected downstream light for upstream signalling in a primarily broadcast passive optical network, to eliminate the need for a light source at each terminal. It shows (for a typical CATV network) that using this technique, and by extracting only 1 dB from light power received at the customer's terminal, a mean upstream signalling rate of around 64 kbits/s from 32 terminals is possible. However, this requires full network synchronisation and modulation at the terminals at 2 Mbaud. In practice, the modulation of the reflected light may be limited to perhaps 1 kbaud if a cheap technology is to be employed. Under these circumstances, the maximum data rate is approximately 550 bits/s and is achieved using subcarrier FDMA. The use of subcarrier FDMA has the added advantage of providing completely asynchronous access from all terminals.
Multichannel System Identification and Detection Using Output Data Techniques (1993)

In multichannel identification and detection (or model-based multichannel detection) problems the parameters of a model are identified from the observed channel process, and the identified model is used to facilitate the detection of a desired signal in the observed process. A model-based multichannel detection algorithm was developed in the context of an innovations- based detection algorithm (IBDA) formulation for surveillance radar system applications. The state space model class was adopted to model the vector channel process because it is more general than the time series model class used in most analyses to date. An IBDA methodology was developed based on an algorithm which uses output data directly and offers computational and performance advantages over alternative techniques. A computer simulation was developed to validate the methodology and the algorithm, and to carry out performance assessments. Simulation results indicate that the algorithm is capable of discriminating between the null hypothesis (clutter plus noise) and the alternative hypothesis (signal plus clutter plus noise). In summary, the applicability of the approach to radar system problems has been established.
Electrodes a few atoms wide made at Caltech (1990)

RETURN TO ISSUEPREVNewsNEXTElectrodes a few atoms wide made at CaltechSTU BORMANCite this: Chem. Eng. News 1990, 68, 48, 8aPublication Date (Print):November 26, 1990Publication History Published online10 November 2010Published inissue 26 November 1990https://pubs.acs.org/doi/10.1021/cen-v068n048.p008ahttps://doi.org/10.1021/cen-v068n048.p008anewsACS PublicationsCopyright © 1990 American Chemical SocietyArticle Views4Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options SUBJECTS:Electrodes,Wires Get e-Alerts
LA FILOSOFÍA POSTESTRUCTURALISTA FEMINISTA: DESARROLLO DE LA IDENTIDAD DE LA ACADÉMICA MEXICANA COMO UNA PRÁCTICA EDUCATIVA DE LA INVESTIGACIÓN. (2011)

a travs de un trabajo de campo que estudiar con profundidad los diferentes factores que intervienen en ello.
Surface ultraviolet radiation (2008)

Abstract One of the main concerns regarding a decrease in stratospheric ozone is the consequential increasein the amount of ultraviolet (UV) radiation that reaches the lower atmosphere and the Earth's surface. Radiationat UV wavelengths where ozone absorbs strongly is detrimental to most biological species, including humanbeings, so a decrease in stratospheric ozone could have a significant impact on the biosphere. This concern hasled to a significant increase in surface UV radiation research over the last two decades since the ratification ofthe Montreal Protocol. Studies include investigations into understanding the complicated absorption and scatteringprocesses involved in the radiative transfer of UV through the atmosphere as well as research on theimpacts of changes in UV radiation. Factors affecting surface UV radiation will be discussed, resources used tostudy surface UV radiation will be described and progress made in our understanding of surface UV radiationover the past two decades will be reviewed.
Adipose conversion of 3T3-L1 cells in a serum-free culture system depends on epidermal growth factor, insulin-like growth factor I, corticosterone, and cyclic AMP. (1990)

A culture system for 3T3-L1 preadipocytes based on a serum-free chemically defined medium containing fetuin, transferrin, and pantothenate is described. In this system, adipose conversion depends on the following conditions. 1) In the presence of high insulin concentrations (1 microM), addition of corticosterone together with 1-methyl-3-isobutylxanthine (MIX) for not more than the first 4 days after confluence to the culture medium induces maximal adipose conversion within 12-14 days. MIX may be replaced by forskolin or permeable analogues of cAMP, indicating that its effect is due to elevated cellular cAMP levels. 2) At low insulin concentrations (1 nM), adipose conversion is reduced. Growth hormone or insulin-like growth factor I together with epidermal growth factor have to be present as a medium supplement together with corticosterone and MIX to get maximal adipose conversion. 3) The induction of adipose conversion by corticosterone and MIX in the presence of either high insulin concentrations or insulin-like growth factor I together with epidermal growth factor is accompanied by post-confluent mitoses. Inhibitors of DNA replication markedly reduce adipose conversion. Fibroblast growth factor and platelet-derived growth factor, although acting as potent mitogens on 3T3-L1 cells, do not support adipose conversion induced by corticosterone and MIX.
Recruitment of<i>Drosophila</i>Polycomb-group proteins by Polycomblike, a component of a novel protein complex in larvae (2008)

Polycomb-group (PcG) proteins are highly conserved epigenetic transcriptional repressors that play central roles in numerous examples of developmental gene regulation. Four PcG repressor complexes have been purified from Drosophila embryos: PRC1, PRC2, Pcl-PRC2 and PhoRC. Previous studies described a hierarchical recruitment pathway of PcG proteins at the bxd Polycomb Response Element (PRE) of the Ultrabithorax (Ubx) gene in larval wing imaginal discs. The DNA-binding proteins Pho and/or Phol are required for target site binding by PRC2, which in turn is required for chromosome binding by PRC1. Here, we identify a novel larval complex that contains the PcG protein Polycomblike (Pcl) that is distinct from PRC1 and PRC2 and which is also dependent on Pho and/or Phol for binding to the bxd PRE in wing imaginal discs. RNAi-mediated depletion of Pcl in larvae disrupts chromosome binding by E(z), a core component of PRC2, but Pcl does not require E(z) for chromosome binding. These results place the Pcl complex (PCLC) downstream of Pho and/or Phol and upstream of PRC2 and PRC1 in the recruitment hierarchy.
Genomic Imprinting in Mammals (2014)

Genomic imprinting affects a subset of genes in mammals and results in a monoallelic, parental-specific expression pattern. Most of these genes are located in clusters that are regulated through the use of insulators or long noncoding RNAs (lncRNAs). To distinguish the parental alleles, imprinted genes are epigenetically marked in gametes at imprinting control elements through the use of DNA methylation at the very least. Imprinted gene expression is subsequently conferred through lncRNAs, histone modifications, insulators, and higher-order chromatin structure. Such imprints are maintained after fertilization through these mechanisms despite extensive reprogramming of the mammalian genome. Genomic imprinting is an excellent model for understanding mammalian epigenetic regulation.
Notes on Mexican Snakes (Ophidia) (1957)

Sixteen species of Mexican snakes are discussed. Range extensions are noted for Lampropeltis triangulum annulata, Lampropeltis getulus nigritus, Pituophis catenifer affinis, Toluca lineata lineata, Salvadora intermedia, Trimorpho- don latifascia, Trimorphodon lambda, and Crotalus trigris. An altitudinal record of 5,200 feet is reported for Crotalus basiliscus basiliscus. Additional data are pre- sented on three rare snakes, Lampropeltis getulus nigritus, Trimorphodon tau, and Leptodiera punctata. Crotalus intermedius gloydi is considered a valid subspecies occupying the Oaxacan highlands. The name Salvadora intermedia richardi Smith appears to be based on an individual variant and should be submerged. The authors question the inclusion of Lampropeltis polyzona Cope in the species complex Lamproeltis triangulum and they suggest that Salvadora bairdi and S. lineata are not specifically distinct but rather are geographic races of S. bairdi. In the course of gathering biological and distributional data on Mexican toads of the Genus Tomodactylus during June and July, 1956, the junior author and his wife, Mary, collected several specimens of Mexican snakes. Some of them are of particular interest in that they constitute new distributional records or are of taxonomic importance. All specimens here discussed are deposited in the Texas Cooperative Wildlife collection, Texas A. and M. College.