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61.
62.
Spectra from a 0.1-cm(-1) resolution absolutely calibrated emission interferometer installed near Eureka, Northwest Territories, Canada (80°N, 86°W), at the Arctic Stratospheric Observatory are presented. The Michelson-type interferometer has a maximum path difference of 10 cm and uses a liquid-N(2)-cooled HgCdTe detector, which covers the spectral region from 650 to 1250 cm(-1). Spectral intervals containing CO(2), HNO(3), and ozone have been modeled with a line-by-line radiative-transfer code and column amounts retrieved for the latter two constituents. The instrument and initial measurements are described. 相似文献
63.
DA Stoyanovosky R Goldman SS Jonnalagadda BW Day HG Claycamp VE Kagan 《Canadian Metallurgical Quarterly》1996,330(1):3-11
Rapidly growing knowledge about the nature and behaviour of breast cancer has led to many treatment modalities. Consequently, the possibilities of individualizing the treatment of breast cancer increase. The major tool for the determination of an optimal treatment plan is the estimation of the extent of the disease: in other words, staging. As a consequence, together with the expected result of the treatment, the stage of the disease gives information on the prognosis of the patient. Current staging systems insufficiently describe the clinically important features of breast cancer with respect to management and outcome: local and regional extent, invasiveness, aggressiveness, the state of dissemination, and the effectiveness of different treatment modalities. For staging of the local and regional extent, histology plays a prominent role and should be incorporated in future staging systems. Histological workup therefore needs standardisation. Histological parameters as tumour size, grade, nodal status, and vascular invasion are also the most important prognostic factors. Many so-called biological prognostic factors are related to the invasiveness and aggressiveness (metastatic potential) of the tumour, and therefore to the prognosis of the patient. However, these factors do not necessarily predict the effectiveness of certain systemic treatments. Only if the biological foundation of a prognostic factor is completely clarified can treatment be based on this knowledge, and the factor will become a predictor for the treatment effect. Many "biological" prognostic factors do not fulfil this main criterion and are therefore not useful for clinical decision making. A clinically useful staging system covers three primary aims: (1) to guide locoregional treatment, (2) to prognosticate the chance of survival, and (3) to indicate who needs what kind of adjuvant treatment. For the conception of a new staging system the following steps should be taken: standardization of all aspects of histology, identification of regional nodal involvement, and validation of prognostic factors with respect to their predictive value to treatment outcome. 相似文献
64.
Developing the ability to recognize a landmark from a visual image of a robot's current location is a fundamental problem in robotics. We consider the problem of PAC-learning the concept class of geometric patterns where the target geometric pattern is a configuration ofk points on the real line. Each instance is a configuration ofn points on the real line, where it is labeled according to whether or not it visually resembles the target pattern. To capture the notion of visual resemblance we use the Hausdorff metric. Informally, two geometric patternsP andQ resemble each other under the Hausdorff metric if every point on one pattern is close to some point on the other pattern. We relate the concept class of geometric patterns to the landmark matching problem and then present a polynomial-time algorithm that PAC-learns the class of one-dimensional geometric patterns. We also present some experimental results on how our algorithm performs. 相似文献
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66.
Meir Kalech Sarit Kraus Gal A. Kaminka Claudia V. Goldman 《Autonomous Agents and Multi-Agent Systems》2011,22(1):151-182
Voting is an essential mechanism that allows multiple agents to reach a joint decision. The joint decision, representing a
function over the preferences of all agents, is the winner among all possible (candidate) decisions. To compute the winning
candidate, previous work has typically assumed that voters send their complete set of preferences for computation, and in
fact this has been shown to be required in the worst case. However, in practice, it may be infeasible for all agents to send
a complete set of preferences due to communication limitations and willingness to keep as much information private as possible.
The goal of this paper is to empirically evaluate algorithms to reduce communication on various sets of experiments. Accordingly,
we propose an iterative algorithm that allows the agents to send only part of their preferences, incrementally. Experiments
with simulated and real-world data show that this algorithm results in an average of 35% savings in communications, while
guaranteeing that the actual winning candidate is revealed. A second algorithm applies a greedy heuristic to save up to 90%
of communications. While this heuristic algorithm cannot guarantee that a true winning candidate is found, we show that in
practice, close approximations are obtained. 相似文献
67.
We provide a technique to detect the singularities of rational planar curves and to compute the correct order of each singularity including the infinitely near singularities without resorting to blow ups. Our approach employs the given parametrization of the curve and uses a μ-basis for the parametrization to construct two planar algebraic curves whose intersection points correspond to the parameters of the singularities including infinitely near singularities with proper multiplicity. This approach extends Abhyankar's method of t-resultants from planar polynomial curves to rational planar curves. We also derive the classical result that for a rational planar curve of degree n the sum of all the singularities with proper multiplicity is (n−1)(n−2)/2. Examples are provided to flesh out our results. 相似文献
68.
Theo Lynn Lisa van der Werff Graham Hunt Philip Healy 《Journal of Computer Information Systems》2016,56(3):185-193
The purpose of this research is to identify the potential information components of an online, real-time trust label, which is proposed as a communication mechanism to encourage trust in cloud service providers and cloud computing products. An online Delphi process was used with 28 cloud computing experts (including vendors, software providers, and legal and business representatives). The proposed label contains 81 information components, covering the cloud service provider (e.g. physical location, legal jurisdiction), the cloud service itself (e.g. data location, security, backup, certification), and a historical service-level summary (e.g. uptime data, support response times). The potential benefits of such a label to encourage trustworthiness perceptions and trust behaviors in the cloud computing environment are explored. Limitations of the study are highlighted, and further research studies are suggested to test the concept of the label and to refine the components of the label itself. 相似文献
69.
70.
Training and learning at work is important as employees competence has to meet organisational requirements for flexibility. This study examines conditions and obstacles in integrating a web-based course at work in order to enhance employees level of competence. Employees view of working condition, competence and how they learn at work is also of importance. A selection of 35 people was made at a company which is part of a large business. The design was quantitative with complementary qualitative data. The employees had a positive attitude towards work despite increasing difficulties in work tasks and an increasing workload, which was the greatest barrier of integrating the web-based course at work. Competence development involved a certain degree of stress, but was outweighed by the fact that it was stimulating and led to the work feeling easier. To manage work, knowledge was obtained primarily by colleagues and company courses. 相似文献