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21.
The purpose of this study was to perform a systematic and comprehensive comparison between the recommended weights of lift (RWL) from the revised NIOSH lifting equation, and the specific biomechanical, psychophysical and physiological criteria that were stated to be used in the equation's development. A composite acceptable load (CAL) table was developed for the 216 conditions presented in the female lifting table of Snook and Ciriello (1991). Each CAL value was calculated to correspond to the most conservative load of the three design criteria. The RWLs caused lumbar compression forces close to the biomechanical limit of 3400 N for lifts below knuckle height, but resulted in compression forces that are much lower at higher lifting heights. At moderate lifting frequencies, the average RWL would be acceptable to more than 95% of female workers according to the psychophysical criterion. At the highest frequencies, the RWL was found to be an average of 63% of the CAL values based on the integration of the psychophysical and physiological criteria. It is recommended that ergonomists acknowledge the very conservative nature of the revised NIOSH lifting equation when using it to evaluate occupational lifting tasks. 相似文献
22.
Victoria J. Hodge Rajesh Krishnan Jim Austin John Polak Tom Jackson 《Neural computing & applications》2014,25(7-8):1639-1655
This paper introduces a binary neural network-based prediction algorithm incorporating both spatial and temporal characteristics into the prediction process. The algorithm is used to predict short-term traffic flow by combining information from multiple traffic sensors (spatial lag) and time series prediction (temporal lag). It extends previously developed Advanced Uncertain Reasoning Architecture (AURA) k-nearest neighbour (k-NN) techniques. Our task was to produce a fast and accurate traffic flow predictor. The AURA k-NN predictor is comparable to other machine learning techniques with respect to recall accuracy but is able to train and predict rapidly. We incorporated consistency evaluations to determine whether the AURA k-NN has an ideal algorithmic configuration or an ideal data configuration or whether the settings needed to be varied for each data set. The results agree with previous research in that settings must be bespoke for each data set. This configuration process requires rapid and scalable learning to allow the predictor to be set-up for new data. The fast processing abilities of the AURA k-NN ensure this combinatorial optimisation will be computationally feasible for real-world applications. We intend to use the predictor to proactively manage traffic by predicting traffic volumes to anticipate traffic network problems. 相似文献
23.
Xiang Jim; Sha Yuhua; Prasad Lata; Delbaere Louis T.J. 《Protein engineering, design & selection : PEDS》1996,9(6):539-543
Structural analysis derived from the crystallographic studyof the chimeric B72.3 antibody illustrated some major atomicinteractions between complementarity determining region (CDR)residues. For example, hydrogen bonds are formed between H35/H95,L50/H97, H53/H55 and H96/L96 respectively. These CDR residuesmay play important roles in the B72.3TAG72 (antibody-antigen)interaction either by direct interaction with the TAG72 antigenor by maintaining a CDR loop conformation through atomic interactionsbetween CDR residues. In order to confirm these assumptions,we altered these CDR residues by site-directed mutagenesis anddetermined binding affinities of these mutant chimeric antibodiesfor the TAG72 antigen in a solid-phase radioimmunoassay. Wefound that H55, H95, H97 and L96 are important CDR residuesfor the B72.3TAG72 interaction. Single amino acid substitutionsof aspartic acid and serine by alanine at H55 of CDR2 and atH95 of CDR3 respectively and of tyrosine by phenylalanine atH97 and L96 of CDR3, significantly reduced the binding affinityfor the TAG72 antigen by 20-, 8-, 16- and 45-fold respectively.Therefore, this study reveals some of the requirements for maintainingthe integrity of the B72.3 antibody combining sites. 相似文献
24.
Jim M. Ridlehuber 《Journal of the American Oil Chemists' Society》1977,54(6):a477-a480
Conventional methods of cottonseed preparation are reviewed and described, including seed cleaning, saw delinting, dehulling,
conditioning, and flaking. The use of screw presses for prepress conditioning ahead of solvent extraction is discussed as
compared to conditioning for direct solvent extraction. Newer methods and proposed alternate methods of cottonseed preparation
are discussed including: abrasive delinting, acid delinting by gas and liquid acid, and the decorticating of undelinted seed.
The effect of cracking rolls, moisture addition, moist cooking and flaking on gossypol gland rupture, the binding of gossypol
to protein, and the effect of these processing or preparation variables on the residual oil in the extracted meal and on the
oil quality are discussed. 相似文献
25.
中国加入WTO后,中国洗涤用品行业面临着新的机遇与挑战,中国洗涤用品市场将面临更加激烈的竞争。由于环保的呼声越来越高,中国已开始在部分地区禁磷。中国洗涤用品工业将如何发展,其前景如何,专家的看法又如何,就这些问题本刊专访了有关人士。 相似文献
26.
Jason Crampton Michael Huth Jim Huan-Pu Kuo 《International Journal on Software Tools for Technology Transfer (STTT)》2014,16(1):31-48
Many business processes are modeled as workflows, which often need to comply with business rules, legal requirements, and authorization policies. Workflow satisfiability is the problem of determining whether there exists a workflow instance that realizes the workflow specification while simultaneously complying with such constraints. This problem has already been studied by the computer security community, with the development of algorithms and the study of their worst-case complexity. These solutions are often tailored to a particular workflow model and are, therefore, of little or no use in analyzing different models; their worst-case complexities are likely to be an unreliable judge of their feasibility; and they lack support for other forms of analysis such as the determination of the smallest number of users required to satisfy a workflow specification. We propose model checking of an NP-complete fragment $\mathsf{LTL }(\mathsf{F })$ of propositional linear-time temporal logic as an alternative solution. We report encodings in LTL(F) that can compute a set of solutions (thus deciding satisfiability), compute minimal user bases and a safe bound on the resiliency of satisfiability under the removal of users. These theoretical contributions are validated through detailed experiments whose results attest to the viability of our proposed approach. 相似文献
27.
Antonio G. González Ignacio A. Jiménez Mercedes P. Núñez Angel G. Ravelo Isabel L. Bazzocchi Orlando M. Muñoz Marcelino A. Aguilar 《Journal of chemical ecology》1994,20(4):823-830
Three new dihydro--agarofuran sesquiterpenes from two species ofMaytenus were isolated and their structures were elucidated by means of1H and13C NMR studies. The differences and similarities noted in the chemical content of the dihydro--agarofuran sesquiterpenes from the fourMaytenus species from Chile are in line with the taxonomic characterization of these species; their geographical distribution is also given. 相似文献
28.
Jim D. Earls Jerry E. White Marvin L. Dettloff Marty J. Null 《Journal of Coatings Technology and Research》2004,1(3):243-245
Epoxidized 10-undecenoic acid triglyceride, an experimental seed oil derivative that has a terminal epoxy group on each of
the three acyl glyceride segments, has been found to have good reactivity with amine curatives and allows room temperature
cures to be obtained. Coatings based on epoxidized 10-undercenoic acid triglyceride have also shown excellent UV stability.
As an example, coatings samples placed in a QUVA chamber exhibit no loss in gloss after 3000 hr of a cycled exposure to high
intensity UV lamps and moisture at temperatures of 50–60°C. In comparison, coatings based on standard liquid epoxy resins
(LERs) and commercially available hydrogenated LERs lose gloss due to chalking/decomposition within 200–800 hr.
Presented at the 81 st Annual Meeting of the Federation of Societies for Coatings Technology, November 12–14, 2003, in Philadelphia,
PA. 相似文献
29.
Quintanar-Reséndiz Ana L. Rodríguez-Santos Francisco Pichardo-Méndez Josué L. Delgado-Gutiérrez Guillermo Ramírez Omar Jiménez Vázquez-Medina Rubén 《Multimedia Tools and Applications》2021,80(13):19513-19538
Multimedia Tools and Applications - It is proposed a forensic method for the capture device identification from digital images, which requires two elements: i) a digital image subject to... 相似文献
30.
A monolithic hybrid fuel cell (MHFC) with a novel configuration was proposed in an effort to improve the fuel cell performance during instantaneous power changes. A modified direct methanol fuel cell (DMFC) with a layer of hydrous ruthenium dioxide (RuO2·xH2O) sandwiched between the anode catalyst layer and membrane was used to demonstrate the principle of the MHFC. Experimental results indicate that the RuO2·xH2O layer is equivalent to a resistor-capacitor transmission line and functions similar to a capacitor in parallel with the anode electrode. The improvement in dynamic response of the MHFC was experimentally confirmed under step current change and square current pulse operating. The ionic conductivity of the RuO2·xH2O layer was also obtained. 相似文献