Work study is an area of construction production rationalization in which with scientific, logical, holistic and system analysis methods of the process we gain optimum in way of work and time of work. Chronometry meth...Work study is an area of construction production rationalization in which with scientific, logical, holistic and system analysis methods of the process we gain optimum in way of work and time of work. Chronometry method is one of the work study methods which is appropriate for recording shorter cyclic processes and is based on statistical sampling theory. Determination of cyclic times and work performances of standard cyclic construction machines （SCCM） is one of key assumptions of dynamic planning of machine work on every construction site. Calculation methods of SCCM work performances arc one of basic research objects in the field of construction organization and technology. Study shows applied chronometry method in work of standard cyclic construction machine. Goal of this study is to accomplish regulation through measured time cycle and compare measured effects with effects obtained with standard methodology of calculating hydraulic excavator practical achievement for gaining regulation in order to determine main reasons which effect work performance on site.展开更多
Accurately measuring inspection time (IT) with computers requires several considerations. They are: 1) Screen redraw period;2) Synchronous and timely image presentation;3) Stimulus duration timing;4) Image scale invar...Accurately measuring inspection time (IT) with computers requires several considerations. They are: 1) Screen redraw period;2) Synchronous and timely image presentation;3) Stimulus duration timing;4) Image scale invariance;5) Stan dardized presentation format (of which image scale invariance is a part). The first consideration dictates a minimum duration available for measuring IT. The second and third are necessary for accurate stimulus duration. The fourth is necessary to provide scale invariant images, that is, images with the same visual angle at a given viewing distance on any computer. And the fifth ensures that participants everywhere respond to the same task. Our computer program em bodies these elements and we make it freely available to any interested party. Data to establish validity and reliability are presented, and normative data on 2518 participants aged 6 to 92 years are available.展开更多
We present an experimental study of the dynamics of shocks generated by the interaction of a double-spot laser in different kinds of targets:simple aluminum foils and foam-aluminum layered targets.The experiment was p...We present an experimental study of the dynamics of shocks generated by the interaction of a double-spot laser in different kinds of targets:simple aluminum foils and foam-aluminum layered targets.The experiment was performed using the Prague PALS iodine laser working at 0.44μm wavelength and irradiance of a few 10^(15)W/cm^(2).Shock breakouts for pure Al and for foam-Al targets have been recorded using time-resolved self-emission diagnostics.Experimental results have been compared with numerical simulations.The shocks originating from two spots move forward and expand radially in the targets,finally colliding in the intermediate region and producing a very strong increase in pressure.This is particularly clear for the case of foam layered targets,where we also observed a delay of shock breakout and a spatial redistribution of the pressure.The influence of the foam layer doped with high-Z(Au)nanoparticles on the shock dynamics was also studied.展开更多
文摘Work study is an area of construction production rationalization in which with scientific, logical, holistic and system analysis methods of the process we gain optimum in way of work and time of work. Chronometry method is one of the work study methods which is appropriate for recording shorter cyclic processes and is based on statistical sampling theory. Determination of cyclic times and work performances of standard cyclic construction machines （SCCM） is one of key assumptions of dynamic planning of machine work on every construction site. Calculation methods of SCCM work performances arc one of basic research objects in the field of construction organization and technology. Study shows applied chronometry method in work of standard cyclic construction machine. Goal of this study is to accomplish regulation through measured time cycle and compare measured effects with effects obtained with standard methodology of calculating hydraulic excavator practical achievement for gaining regulation in order to determine main reasons which effect work performance on site.
文摘Accurately measuring inspection time (IT) with computers requires several considerations. They are: 1) Screen redraw period;2) Synchronous and timely image presentation;3) Stimulus duration timing;4) Image scale invariance;5) Stan dardized presentation format (of which image scale invariance is a part). The first consideration dictates a minimum duration available for measuring IT. The second and third are necessary for accurate stimulus duration. The fourth is necessary to provide scale invariant images, that is, images with the same visual angle at a given viewing distance on any computer. And the fifth ensures that participants everywhere respond to the same task. Our computer program em bodies these elements and we make it freely available to any interested party. Data to establish validity and reliability are presented, and normative data on 2518 participants aged 6 to 92 years are available.
基金funding from the Euratom research and training programme 2014-2018 and 2019-2020 under grant agreement No.633053supported by the European Union under the Laserlab program,by the Competitiveness Program of NRNU MEPh I,Russia,and by the Czech Ministry of Education,Youth and Sports(CMEYS),projects LTT17015 and LM2018114。
文摘We present an experimental study of the dynamics of shocks generated by the interaction of a double-spot laser in different kinds of targets:simple aluminum foils and foam-aluminum layered targets.The experiment was performed using the Prague PALS iodine laser working at 0.44μm wavelength and irradiance of a few 10^(15)W/cm^(2).Shock breakouts for pure Al and for foam-Al targets have been recorded using time-resolved self-emission diagnostics.Experimental results have been compared with numerical simulations.The shocks originating from two spots move forward and expand radially in the targets,finally colliding in the intermediate region and producing a very strong increase in pressure.This is particularly clear for the case of foam layered targets,where we also observed a delay of shock breakout and a spatial redistribution of the pressure.The influence of the foam layer doped with high-Z(Au)nanoparticles on the shock dynamics was also studied.
