Energy consumption of block-cutting machines represents a major cost item in the processing of travertines and other natural stones. Therefore, determining the optimum sawing conditions for a particular stone is of ma...Energy consumption of block-cutting machines represents a major cost item in the processing of travertines and other natural stones. Therefore, determining the optimum sawing conditions for a particular stone is of major importance in the natural stone-processing industry. An experimental study was carried out utilizing a fully instrumented block-cutter to investigate the sawing performances of five different types of travertine blocks during cutting with a circular diamond saw. The sawing tests were performed in the down-cutting mode. Performance measurements were determined by measuring the cutting speed and energy consumption. Then, specific energy was determined. The one main cutting parameter, cutting speed, was varied in the investigation of optimum cutting performance. Furthermore, some physico-mechanical properties of file travertine blocks were determined in the laboratory. As a result, it is found that the energy consumption （specific energy） of block cutting machines is highly affected by cutting speed. It is determined that specific energy value usually decreases when cutting speed increases. When the cutting speed is higher than the determined value, the diamond saw can become stuck in the travertine block; this situation can be a problem for the block-cutting machine. As a result, the optimum cutting speed obtained for the travertine mines examined is approximately 1.5-2.0 m/min.展开更多
＂We Are the Furrow of His Brow＂ is the graffiti altered from ＂Beware of the Furrow of His Brow＂ or ＂The Furrow of His Brow＂ on the hood of an oven in a separated black town Ruby. Young people of Ruby change the ...＂We Are the Furrow of His Brow＂ is the graffiti altered from ＂Beware of the Furrow of His Brow＂ or ＂The Furrow of His Brow＂ on the hood of an oven in a separated black town Ruby. Young people of Ruby change the words because they feel regretted contriving to shoot an assumed guilty woman living in the nearby convent. However, whether the woman Consolata and the other four women at the convent are dead remains mysterious. There are some descriptions of magics in Paradise in which the most magical abilities are Connie＇s ＂bat vision＂ and ＂stepping in＂. This paper demonstrates the ways that Morrison manifests magic realism in Paradise including multiple narrative timelines, ambiguous writing, reconstituted marginal figures and naturally blended reality. Primarily in thefour ways Morrison presents how she utilizes magic realism genre to depict the changeable world penetrating through the appearance.展开更多
The round-tailed homed lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modest...The round-tailed homed lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modestum and its dependence on stones by placing a lizard in one of two microhabitats （uniform sand or sand with surface rocks approximately the same size as lizards）. An observer who knew which microhabitat contained the lizard was asked to locate the lizard visually. Latency to detec- tion was longer and probability of no detection within 60 s was higher for lizards on rock background than on bare sand. In arenas where lizards could choose to occupy rock or bare sand, much higher proportions selected rocky backgrounds throughout the day; at night all lizards slept among stones. A unique posture gives P modestum a rounded appearance similar to many natural stones. Lizards occasionally adopted the posture, but none did so in response to a nearby experimenter. Stimuli that elicit the posture are unknown. That P. modestum is better camouflaged among rocks than on bare sand and prefers to occupy rocky areas suggests that special resemblance to rocks （masquerade） enhances camouflage attributable to coloration and immobility.展开更多
文摘Energy consumption of block-cutting machines represents a major cost item in the processing of travertines and other natural stones. Therefore, determining the optimum sawing conditions for a particular stone is of major importance in the natural stone-processing industry. An experimental study was carried out utilizing a fully instrumented block-cutter to investigate the sawing performances of five different types of travertine blocks during cutting with a circular diamond saw. The sawing tests were performed in the down-cutting mode. Performance measurements were determined by measuring the cutting speed and energy consumption. Then, specific energy was determined. The one main cutting parameter, cutting speed, was varied in the investigation of optimum cutting performance. Furthermore, some physico-mechanical properties of file travertine blocks were determined in the laboratory. As a result, it is found that the energy consumption （specific energy） of block cutting machines is highly affected by cutting speed. It is determined that specific energy value usually decreases when cutting speed increases. When the cutting speed is higher than the determined value, the diamond saw can become stuck in the travertine block; this situation can be a problem for the block-cutting machine. As a result, the optimum cutting speed obtained for the travertine mines examined is approximately 1.5-2.0 m/min.
文摘＂We Are the Furrow of His Brow＂ is the graffiti altered from ＂Beware of the Furrow of His Brow＂ or ＂The Furrow of His Brow＂ on the hood of an oven in a separated black town Ruby. Young people of Ruby change the words because they feel regretted contriving to shoot an assumed guilty woman living in the nearby convent. However, whether the woman Consolata and the other four women at the convent are dead remains mysterious. There are some descriptions of magics in Paradise in which the most magical abilities are Connie＇s ＂bat vision＂ and ＂stepping in＂. This paper demonstrates the ways that Morrison manifests magic realism in Paradise including multiple narrative timelines, ambiguous writing, reconstituted marginal figures and naturally blended reality. Primarily in thefour ways Morrison presents how she utilizes magic realism genre to depict the changeable world penetrating through the appearance.
文摘The round-tailed homed lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modestum and its dependence on stones by placing a lizard in one of two microhabitats （uniform sand or sand with surface rocks approximately the same size as lizards）. An observer who knew which microhabitat contained the lizard was asked to locate the lizard visually. Latency to detec- tion was longer and probability of no detection within 60 s was higher for lizards on rock background than on bare sand. In arenas where lizards could choose to occupy rock or bare sand, much higher proportions selected rocky backgrounds throughout the day; at night all lizards slept among stones. A unique posture gives P modestum a rounded appearance similar to many natural stones. Lizards occasionally adopted the posture, but none did so in response to a nearby experimenter. Stimuli that elicit the posture are unknown. That P. modestum is better camouflaged among rocks than on bare sand and prefers to occupy rocky areas suggests that special resemblance to rocks （masquerade） enhances camouflage attributable to coloration and immobility.
