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1.
Knowledge and action rest upon a background of shared expectations. ‘Technology’ refers to a particular background of expectations. Key words are: efficiency, productivity, utility, order, control, and objectivity. If, however, such expectations are carried too far, the behavior of mere functionaries becomes established: one becomes preoccupied with the completion of assignments with no time or inclination for the asking of troublesome questions. This paper examines one of the consequences of such behavior. A model is presented illustrating how organizational systems selectively distort assessments. Within such systems, favorable information is more likely to survive and thus a distorting tendency emerges. Such systemic distortions do not require individual fraud or deceit; the ‘normal’ behaviors of functionaries suffice. We claim that these functionary practices arise from taking the technological expectations too far. Examples are presented. Suggestions on avoiding functionary behavior and systemic distortions are discussed. We suggest that greater emphasis be given to the notion of ‘citizen engineers’.  相似文献   

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By heating mixtures of H3BO3, TiCl4, and NbCl5 with urea in 1:6 molar ratios in the 900–1000 °C range, nanoparticles of BN, TiN, and NbN have been obtained, respectively. The nanoparticles are crystalline and have been characterized by electron microscopy and other techniques. By carrying out the urea reaction over Au islands deposited on Si substrates, nanowires of TiN could be obtained.  相似文献   

3.
Infrared optical constants collected from the literature are tabulated. The data for the noble metals and Al, Pb, and W can be reasonably fit using the Drude model. It is shown that -epsilon1(omega) = epsilon2(omega) approximately omega(2)(p)/(2omega(2)(tau)) at the damping frequency omega = omega(tau). Also -epsilon1(omega(tau)) approximately - (1/2) epsilon1(0), where the plasma frequency is omega(p).  相似文献   

4.
Adam   《Technology in Society》2008,30(3-4):423
Perhaps no three countries have benefited from the globalization of science and technology (S&T) more than India, China, and the United States. All three have leveraged the growing internationalization of innovation to offset weaknesses in their own national innovation systems. Still, globalization raises critical questions of autonomy, security, and equality, and in turn the political struggle over these three issues shapes the pace and scope of the globalization of S&T. Significant deterioration on any one of these criterion could lead to substantially less support among policy makers and the public for the globally networked system of innovation that appears to be emerging.  相似文献   

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The concepts of connectivity, localization, and frustration are explored in relation to glass formation in amorphous materials. First, the concept of eigenclusters to geometrically characterize correlations in amorphous materials is introduced, and discussed in detail for both the Ising ferromagnet and Ising spin glass models. Second, a new, glass-forming percolation model that contains frustration as the essential ingredient, and exhibits two percolation transitions, is discussed. This new model gives new insights into frustrated systems, and applications to the Ising spin glass model and other glass-forming systems are discussed. In particular, we propose the possibility that the occurrence of a percolation-type transition at temperatures above the glass transition temperature may be a general feature of glass-forming systems. The important role of computer simulations in probing the mechanism of glass formation is emphasized.  相似文献   

7.
Abstract

Photographic images are capable of providing both creator and viewer with a highly aesthetic, intellectually stimulating, emotionally charged, ineffable experience. However, that potential may be very limited. The quality of the relationship starts with the intent and attention of photographer and viewer respectively, where both must be able to draw on similar referents, similar emotional responses, and similar aesthetic assumptions about interpretation. To the degree that parties in the communication process share similar intentions in understanding images, I submit that images can be transcendental equivalents.  相似文献   

8.
We construct in dimension two a mirror that reflects collimated rays into a set of directions that amplify the image and an optical lens so that collimated rays are refracted into a set of directions with a prescribed magnification factor. The profiles of these optical surfaces are given by explicit formulas involving the Legendre transformation.  相似文献   

9.
When Ronald Reagan first came to power two years ago, many Americans believed that his administration would bring about dramatic and fundamental changes in American politics. In this paper, the author contends that although it is still too early to fully assess the effects of "Reaganism" on the country in general, it is not too early to evaluate the results in terms of the altered relationships between government, business, and society. The author goes on to say that the 1982 congressional election results already show that the American people are fast becoming disillusioned with the Reagan administration. In conclusion, the author maintains that only when the U.S. chooses a visionary leader who is capable of defining--or redefining--"progress." will American politics undergo a real revolutionary change.  相似文献   

10.
Atherosclerosis, particularly coronary atherosclerosis, is accelerated in renal failure, as originally postulated by Belding Scribner. But in contrast to previous opinion, myocardial infarction from coronary heart disease is not the single major cause of cardiac death in dialyzed patients, the most common causes being sudden death and cardiac failure. Apart from coronary heart disease, the following cardiomyopathic features are prevalent and explain a large part of the excess cardiac risk: cardiomyocyte dropout, left ventricular hypertrophy, cardiac interstitial fibrosis, microangiopathy with arteriolar thickening, and capillary deficit as well as reduced ischemia tolerance. Recently, cardiovascular risk factors related to abnormal mineral metabolism, particularly phosphate and vitamin D, have gained unanticipated importance. Controlled evidence has become available concerning intervention with ACE inhibitors, angiotensin receptor blockers, β‐blockers, and statins in dialyzed patients. It is imperative that apart from the “classical” cardiovascular risk factors that do not exhaustively explain the excessive cardiovascular risk in dialyzed patients, novel pathomechanisms are considered and investigated; potential examples include depression, sleep abnormalities, etc. The above arguments do not negate the fact that today's modalities of renal replacement therapy are poor substitutes for the normal kidney's function so that as a result alternative strategies, e.g., daily dialysis, may also dramatically improve cardiovascular risk.  相似文献   

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This review compiles various nanostructures fabricated by a distinct “dry autoclaving” approach, where the chemical reactions are carried out without solvents; above the dissociation temperature of the chemical precursor(s) at elevated temperature in a closed reactor. The diversity to fabricate carbides (SiC, Mo2C, WC), oxides (VOx‐C, ZnO, Eu2O3, Fe3O4, MoO2), hexaborides (LaB6, CeB6, NdB6, SmB6, EuB6, GdB6), nitrides (TiN, NbN, TaN), phosphides (PtP2, WP), sulfides (ZnS, FeS/C, SnS/C, WS2, WS2/C), and selenides (Zn1‐xMnxSe/C, Cd1‐xMnxSe/C), with various shapes and sizes is accounted with plausible applications. This unique single‐step, solvent‐free synthetic process opens up a new route in the growing nanomaterials science; owing to its considerable advantages on the existing approaches.  相似文献   

13.
This paper is concerned mainly with the problem of the origin of highT c .s-Wave vs.d-wave pairing, the isotope effect, and the strong coupling of the carriers to low-frequency optical phonon modes are discussed. This latter strong coupling is sufficient to provide highT c .The work of VZK was sponsored by the U.S. Office of Naval Research Contract No. N00014-92-F0006.  相似文献   

14.
In this study, the effects of Pb, Nb, La, and Y replacements were investigated on Bi-based superconducting materials. In preparing the samples, we used a method called solid-state reaction method. The patterns of the X-ray diffraction of all samples indicated presence of Bi-2212 and Bi-2223 phases. The results obtained from XRD revealed that with increase of the melting point of substation elements, the Bi-2223 phase decreased while the Bi-2212 phase and impurity phases of samples grew. From the electrical resistivity measurements using the four-probe method, it was found that sample A with Pb and sample B with La replacements had the maximum and minimum critical temperatures of 111.4 and 81.6 K, respectively. Based on hysteresis loop (M–H) measurement using Bean’s model, estimation of critical current density (Jc) showed that sample A with Pb and sample B with La substitution had the maximum and minimum values respectively. These results may be due to the melting point of these elements with values of 888, 1512, 2315, and 2425 °C for PbO, Nb2O5, La2O3, and Y2O3, respectively. These elements were replaced by Bi2O3 with a melting point of 817 ° C. Further, the samples were prepared at the temperature of 845 °C. It seems at this temperature, these elements not only dissolve within the main matrix and participate in the formation of the Bi-2212 phase during the sintering process but they also participate in the development of the variety of the impurity phases as confirmed by XRD results.  相似文献   

15.
Charles Townes is renowned as the inventor of the maser and for his work on molecular spectroscopy and astronomy. Engineering has been an important element of his career, which illustrates how fruitful a combination of scientific and engineering knowledge can be. The author describes the life and work of Townes and how he developed microwave spectroscopy and the maser, and his interest in astronomy  相似文献   

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沃伦·巴菲特有两句话引用率很高,一句是"在别人贪婪时恐惧,在别人恐惧时贪婪",另一句是"只有在退潮的时候,你才知道谁在裸泳".人们之所以常提,并乐此不疲,大抵是认定这两句话能概括巴菲特价值投资的思想要义.事实是这样的吗?  相似文献   

20.
Accidents, mileage, and the exaggeration of risk   总被引:4,自引:2,他引:2  
The usual interpretation of accidents per mile as a measure of risk exaggerates the apparent risk of low-mileage groups--for example, teenagers and the elderly. The assumption of a linear proportional relationship between mileage and accidents is shown not to fit obtained data. Neither would it be expected to fit hypothetical data derived from a "standard driver" or a group of equally competent drivers driving different numbers of miles. People driving low mileages tend to accumulate much of their mileage on congested city streets with two-way traffic and no restriction of access, while high-mileage drivers typically accumulate most of those miles on freeways or other divided multilane highways with limited access. Because the driving task is simpler, the accident rate per mile is much lower on freeways, and beyond a certain point, a person driving half as many miles as another would be expected to have considerably more than half as many accidents. This and other considerations lead to the suggestion that an induced exposure approach would be a more valid method of correcting accident rates for mileage.  相似文献   

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