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101.
The effects of the operability of the prototype CRT workstation and room illumination upon observer's performance were studied. In the experiment of reading CT images as a routine daily work at the CRT workstation, the average time required to analyse one CT image under a room illuminance of 100 lux was longer than that on the film viewbox. Prolongation occurred due mainly to the longer time required to retrieve and to arrange images as observers desired, and the limitation to the number of images simultaneously displayed on two CRT monitors. In the ROC studies to detect small pulmonary nodules on CRT images of computed radiography with imaging plate, illuminance around 170 lux showed the best result and a statistically significant difference (P less than 0.05) as compared with that of 480 lux. In addition to the radiologist's visual performance, room illumination must also be taken into consideration as it influences the observer's performance and diagnostic efficiency.  相似文献   
102.
We report here that human immunodeficiency virus type 2 (HIV-2) envelope glycoprotein (gp105), but not HIV-1 gp120, can bind to CD8 molecules as well as to CD4 molecules on human T cells. This phenomenon may lead to differences in the life cycles of HIV-1 and HIV-2, and it may be related to the differences in disease manifestations of HIV-1 and HIV-2 infection, including longer survival of HIV-2-infected patients.  相似文献   
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104.
This paper tackles the main changes that have taken place in the mechanical worldview of simple, self-regulating and intelligent machines, and studies their repercussions at the ethical and organisational level. These views of machines agree with the scientific, human-relations and postmodern proposals in organisation theory, in that they are in fact reflections on human nature which depend on metaphorical devices within which the machine metaphor is central.If we were only to govern our actions by the reflection of the inert world's irrevocable laws in our own consciousness, we would be completely unmoral, or to put it better, amoral; Good and Bad would lack meaning for us... A. Caso A System is an imaginary machine... A. Smith  相似文献   
105.
106.
A new architecture for serial access memory is described that enables a static random access memory (SRAM) to operate in a serial access mode. The design target is to access all memory address serially from any starting address with an access time of less than 10 ns. This can be done by all initializing procedure and three new circuit techniques. The initializing procedure is introduced to start the serial operation at an arbitrary memory address. Three circuit techniques eliminate extra delay time caused by an internal addressing of column lines, sense amplifiers, word lines, and memory cell blocks. This architecture was successfully implemented in a 4-Mb CMOS SRAM using a 0.6 μm CMOS process technology. The measured serial access time was 8 ns at a single power supply voltage of 3.3 V  相似文献   
107.
This paper describes the results of pilot plant testwork on a novel single stage zinc solution purification process using a vibratory reactor. This technique was modified for continuous cadmium cementation. There are distinct advantages to combining an intensely agitated reactor with a high mass of precipitant per unit volume in the form of granular zinc instead of zinc dust, including significant reduction of cementation agent consumption and substantial upgrading of the cadmium cement. This technique has the potential to minimize equipment, reduce plant size, and diminish operating costs.  相似文献   
108.
Toyota electronic modulated air suspension system for the 1986Soarer   总被引:1,自引:0,他引:1  
An electronically controlled air-suspension system is described that uses sensors to detect vehicle speed, throttle position, steering angle, height, and other factors related to vehicle attitude. Its electronic control unit (ECU) drives the actuators to control spring rate, damping force, and height. As a result, the system reduces changes in vehicle attitude such as rolls, dives, squats, etc., and also provides stable maneuverability in high-speed cruising and improved drive characteristics on rough roads. A newly developed single-chip microcomputer is used in the ECU. The actuators for the sporting rate and damping force use DC motors. The system also allows drivers to select preferred suspension characteristics from four modes, and displays on a CRT the suspension status  相似文献   
109.
Pinnipeds (Otariidae, Odobenidae, and Phocidae) in the order Carnivora have one or two types (Hb I and Hb II) of hemoglobin components. These hemoglobins consist of identical beta chains and different alpha chains. We determined the complete amino acid sequences of the hemoglobin beta chain of three species of Otariidae (Australian sea lion, South American sea lion, and northern sea lion) and two species of Phocidae (ringed seal and harp seal) from intact beta chain and chemical cleavage fragments. The sequences are similar to beta chains of the already known sequences of pinnipeds. These sequences were compared with those of other carnivores (Mustelidae, Ursidae, Canidae, and Felidae) and adult human hemoglobin beta chain. Using Artiodactyla (pig) as an outgroup, we find that the tree constructed by means of phylogenetic analysis shows that Odobenidae is closest to Otariidae, and that Otariidae and Odobenidae are closer to Mustelidae than to Phocidae.  相似文献   
110.
Adriamycin hydrochloride was microencapsulated with ethylcellulose by a phase separation method to develop a prolonged release dosage form. Polyisobutylene (PIB) was used as a coacervation-inducing agent to control the particle size and drug release rate of the resultant microcapsules. With increasing the concentration of PIB (1 to 3 %) the average diameter of the microcapsules decreased, due to the fact that the microcapsules were discreted to a single microcapsule. At low concentration of PIB, the resultant microcapsules were agglomerated, which resulted in increasing the size. The microcapsules prepared with PIB 2 % prolonged desirably the drug release from the microcapsules. A little size effects of the microcapsules on the drug release rate was found for the microcapsules with PIB 2 % and 3 %.  相似文献   
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