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51.
Research into national innovation systems (NISs) has received extensive academic and policy attention, and is especially relevant with latecomer countries seeking to innovate in challenging industrial environments. In playing catch up with their early industrializing counterparts, methods of learning take on increased importance in determining industrial success for latecomers. The wind turbine technology innovation system is one that is highly dependent on both the extent of the national learning processes and the strength of the national social-institutional setting. This research investigates the case of Taiwan, a country which has embarked on a program to build its national innovative capacity in wind turbine technologies with specific emphasis on Taiwan’s social sector. Within this system, the spotlight will be on four types of learning processes that interplay during wind turbine development: learning by searching, learning by doing, learning by using, and learning by interacting. Through a case study of the emergence of Taiwan’s burgeoning large-scale wind power technology initiatives, the paper aims to add to the understanding on how methods of learning impact upon the success of innovation systems. The findings show that the industry’s future prospects are constrained because of the limited learning by interacting processes between turbine component producers, turbine owners, and researchers and because of weaknesses in the institutional framework. This research also recognizes the importance that culture has on dominant forms of learning.  相似文献   
52.

This paper seeks to understand why climate information is produced differently from country to country. To do this, we critically examined and compared the social and scientific values that shaped the production of three national climate scenarios in the Netherlands, Switzerland and the UK. A comparative analysis of documentary materials and expert interviews linked to the climate scenarios was performed. Our findings reveal a new typology of use-inspired research in climate science for decision-making: (i) innovators, where the advancement of science is the main objective; (ii) consolidators, where knowledge exchanges and networks are prioritised; and (iii) collaborators, where the needs of users are put first and foremost. These different values over what constitutes ‘good’ science for decision-making are mirrored in the way users were involved in the production process: (i) elicitation, where scientists have privileged decision-making power; (ii) representation, where multiple organisations mediate on behalf of individual users; and (iii) participation, where a multitude of users interact with scientists in an equal partnership. These differences help explain why climate knowledge gains its credibility and legitimacy differently even when the information itself might not be judged as salient and usable. If the push to deliberately co-produce climate knowledge is not sensitive to the national civic epistemology at play in each country, scientist–user interactions may fail to deliver more ‘usable’ climate information.

  相似文献   
53.
When characterizing environmental radioactivity, whether in the soil or within concrete building structures undergoing remediation or decommissioning, it is highly desirable to know the radionuclide depth distribution. This is typically modeled using continuous analytical expressions, whose forms are believed to best represent the true source distributions. In situ gamma ray spectroscopic measurements are combined with these models to fully describe the source. Currently, the choice of analytical expressions is based upon prior experimental core sampling results at similar locations, any known site history, or radionuclide transport models. This paper presents a method, employing multiple in situ measurements at a single site, for determining the analytical form that best represents the true depth distribution present. The measurements can be made using a variety of geometries, each of which has a different sensitivity variation with source spatial distribution. Using non-linear least squares numerical optimization methods, the results can be fit to a collection of analytical models and the parameters of each model determined. The analytical expression that results in the fit with the lowest residual is selected as the most accurate representation. A cursory examination is made of the effects of measurement errors on the method.  相似文献   
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The “filter model” has been developed to explain the biologic effects of radiation and chemicals. We have examined nearly 300 sets of dose response data, of which 50 are presented here. Responses (induced by radiation and chemicals) which have been examined include in vitro survival studies on animal and plant tissues, induction of cellular aberrations and time to tumor or death. Similar data from in vivo studies has also been examined. All of the data appear to fit the model R = a lnD + b(lnD)2 + c, where R is the response, a and b are parameters fitted by regression to a particular set of data, and c is the response at zero (or lowest) dose. By writing this model in exponential form, it can be seen that the response R results from multistage filtering (by net amounts a and b) of the initial dose, D. The threshold is obtained from this model as the point, D?T, at which the second derivative becomes zero. This is given by D?T = exp(1 ? a2b) when a and b are oppositelt signed.  相似文献   
56.
Various suggested definitions of the term “traceability” are discussed from the standpoint of proposed adoption and use of the concept by the International Organization of Legal Metrology.  相似文献   
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A technique is described for measuring pressure within the amniotic cavity and within fetal vessels and/or body compartments. Two saline-filled catheters were connected at one end to needles inserted during indicated invasive procedures and at the other to silicon strain gauge transducers. In 36 pregnancies with normal liquor volume, stable intra-amniotic pressure (IAP, range 1–14 mmHg) increased with gestation (r=0·48, p<0·01). In pregnancies complicated by severe oligohydramnios, IAP was ≤ 1 mm Hg and rose to normal levels with saline amnioinfusion. Raised IAP (range 17–26 mm Hg), found in pregnancies with gross polyhydramnios, fell with drainage of amniotic fluid. Subtraction manometry was used to determine supra-amniotic pressure within the intervillus space, umbilical vein, umbilical artery, abdominal and thoracic cavities, and the urinary tract in normal and/or pathological fetuses. Low intravesical and intrapelvicalyceal pressures (median 6·5, range 2–10 mmHg) were noted in fetuses with obstructive uropathies. Intrauterine subtraction manometry appears to be a useful tool in the understanding of fetal pathophysiology and may be of clinical benefit in the therapeutic drainage and infusion of amniotic fluid and in the assessment of certain fetal disease states.  相似文献   
59.
The blood feeding vampire bats emerged from New World leaf-nosed bats that fed on fruit and insects. Plasminogen activator, a serine protease that regulates blood coagulation, is known to be expressed in the saliva of Desmodus rotundus (common vampire bat) and is thought to be a key enzyme for the emergence of blood feeding in vampire bats. To better understand the evolution of this biological function, we studied the plasminogen activator (PA) genes from all vampire bat species in light of their feeding transition to bird and subsequently mammalian blood. We include the rare species Diphylla ecaudata and Diaemus youngi, where plasminogen activator had not previously been studied and demonstrate that PA gene duplication observed in Desmodus is not essential to the vampire phenotype, but relates to the emergence of predominant mammalian blood feeding in this species. Plasminogen activator has evolved through gene duplication, domain loss, and sequence evolution leading to change in fibrin-specificity and susceptibility to plasminogen activator inhibitor-1. Before undertaking this study, only the four plasminogen activator isoforms from Desmodus were known. The evolution of vampire bat plasminogen activators can now be linked phylogenetically to the transition in feeding behavior among vampire bat species from bird to mammalian blood. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
60.
How best to optimize the biodiversity gain from agri-environment schemes (AES) has recently been identified as a key policy-relevant question. Here, the effects of two features of lowland agricultural landscapes on the abundance and diversity of larger moths are contrasted. Although both features bring about positive effects, hedgerow trees have a larger impact than 6 m wide grassy field margins. Whilst AES payments are given to create and maintain grass margins, no financial reward is currently offered for the retention of hedgerow trees. Furthermore, it was only in areas where the amount of land under AES was experimentally increased, by targeting farmers, that the presence of hedgerow trees resulted in a substantially higher abundance (+60%) and diversity (+38%) of moths. Thus, by using larger moths as bio-indicators of landscape-scale quality, it is demonstrated that improvements to the cost-effectiveness of AES could be achieved, firstly, by providing more appropriate financial rewards to farmers for different landscape features, and secondly, through landscape-scale targeting of farmers to encourage participation in AES.  相似文献   
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