The DQE of an electron image recording system

Author(s):  
K.-H. Herrmann ◽  
D. Krahl ◽  
H.-P Rust

The high detection quantum efficiency (DQE) is the main requirement for an imagerecording system used in electron microscopy of radiation-sensitive specimens. An electronic TV system of the type shown in Fig. 1 fulfills these conditions and can be used for either analog or digital image storage and processing [1], Several sources of noise may reduce the DQE, and therefore a careful selection of various elements is imperative.The noise of target and of video amplifier can be neglected when the converter stages produce sufficient target electrons per incident primary electron. The required gain depends on the type of the tube and also on the type of the signal processing chosen. For EBS tubes, for example, it exceeds 10. The ideal case, in which all impinging electrons create uniform charge peaks at the target, is not obtainable for several reasons, and these will be discussed as they relate to a system with a scintillator, fiber-optic and photo-cathode combination as the first stage.

Author(s):  
K.-H. Herrmann ◽  
W. D. Rau ◽  
R. Sikeler

Quantitative recording of electron patterns and their rapid conversion into digital information is an outstanding goal which the photoplate fails to solve satisfactorily. For a long time, LLL-TV cameras have been used for EM adjustment but due to their inferior pixel number they were never a real alternative to the photoplate. This situation has changed with the availability of scientific grade slow-scan charged coupled devices (CCD) with pixel numbers exceeding 106, photometric accuracy and, by Peltier cooling, both excellent storage and noise figures previously inaccessible in image detection technology. Again the electron image is converted into a photon image fed to the CCD by some light optical transfer link. Subsequently, some technical solutions are discussed using the detection quantum efficiency (DQE), resolution, pixel number and exposure range as figures of merit.A key quantity is the number of electron-hole pairs released in the CCD sensor by a single primary electron (PE) which can be estimated from the energy deposit ΔE in the scintillator,


Author(s):  
Gerd Nufer ◽  

Guerrilla marketing is the selection of atypical and non-dogmatic marketing activities that aim to achieve the greatest possible impact – in the ideal case with a comparable minimum investment. Guerrilla marketing has developed into a basic strategy overarching the marketing mix, a basic marketing policy attitude for market development that goes off the beaten track to consciously seek new, unconventional, previously disregarded, possibly even frown-upon possibilities for the deployment of tools. Digital marketing tools such as social media provide new ways and promising opportunities for innovative guerrilla marketing. This article provides an overview of innovative digital guerrilla marketing. It describes and structures guerrilla marketing in a novel form and shows illustrating examples as well as developmental trends.


Author(s):  
R. A. Crowther

The reconstruction of a three-dimensional image of a specimen from a set of electron micrographs reduces, under certain assumptions about the imaging process in the microscope, to the mathematical problem of reconstructing a density distribution from a set of its plane projections.In the absence of noise we can formulate a purely geometrical criterion, which, for a general object, fixes the resolution attainable from a given finite number of views in terms of the size of the object. For simplicity we take the ideal case of projections collected by a series of m equally spaced tilts about a single axis.


2021 ◽  
Vol 13 (15) ◽  
pp. 8247
Author(s):  
Dimitrios N. Vlachostergios ◽  
Christos Noulas ◽  
Anastasia Kargiotidou ◽  
Dimitrios Baxevanos ◽  
Evangelia Tigka ◽  
...  

Lentil is a versatile and profitable pulse crop with high nutritional food and feed values. The objectives of the study were to determine suitable locations for high yield and quality in terms of production and/or breeding, and to identify promising genotypes. For this reason, five lentil genotypes were evaluated in a multi-location network consisting of ten diverse sites for two consecutive growing seasons, for seed yield (SY), other agronomic traits, crude protein (CP), cooking time (CT) and crude protein yield (CPY). A significant diversification and specialization of the locations was identified with regards to SY, CP, CT and CPY. Different locations showed optimal values for each trait. Locations E4 and E3, followed by E10, were “ideal” for SY; locations E1, E3 and E7 were ideal for high CP; and the “ideal” locations for CT were E3 and E5, followed by E2. Therefore, the scope of the cultivation determined the optimum locations for lentil cultivation. The GGE-biplot analysis revealed different discriminating abilities and representativeness among the locations for the identification of the most productive and stable genotypes. Location E3 (Orestiada, Region of Thrace) was recognized as being optimal for lentil breeding, as it was the “ideal” or close to “ideal” for the selection of superior genotypes for SY, CP, CT and CPY. Adaptable genotypes (cv. Dimitra, Samos) showed a high SY along with excellent values for CP, CT and CPY, and are suggested either for cultivation in many regions or to be exploited in breeding programs.


Focaal ◽  
2010 ◽  
Vol 2010 (57) ◽  
pp. 79-94 ◽  
Author(s):  
Janet McLaughlin

This article analyzes the ideology and practice of multi-unit competition that pervades neoliberal subjectivities and produces the “ideal” flexible worker within contemporary global capitalism. It demonstrates how state and capitalist interests converge to influence the selection of the ideal transnational migrant worker, how prospective migrants adapt to these expectations, and the consequences of such enactments, particularly for migrants, but also for the societies in which they live and work. Multiple levels of actors—employers, state bureaucrats, and migrants themselves—collude in producing the flexible, subaltern citizen, which includes constructions and relations of class, race, gender, and nationality/citizenship. The case study focuses on Mexican and Jamaican participants in Canada's Seasonal Agricultural Workers Program, a managed migration program that legally employs circular migrant farmworkers from Mexico and several English-speaking Caribbean countries in Canadian agriculture.


The selection of hospital sites is one of the most important choice a decision maker has to take so as to resist the pandemic. The decision may considerably affect the outbreak transmission in terms of efficiency , budget, etc. The main targeted objective of this study is to find the ideal location where to set up a hospital in the willaya of Oran Alg. For this reason, we have used a geographic information system coupled to the multi-criteria analysis method AHP in order to evaluate diverse criteria of physiological positioning , environmental and economical. Another objective of this study is to evaluate the advanced techniques of the automatic learning . the method of the random forest (RF) for the patterning of the hospital site selection in the willaya of Oran. The result of our study may be useful to decision makers to know the suitability of the sites as it provides a high level of confidence and consequently accelerate the power to control the COVID19 pandemic.


2020 ◽  
Vol 1 (2) ◽  
pp. 142
Author(s):  
Dasarius Gulo

In the process of selecting Indonesian Workers (TKI) based on quality at PT. Adila Prezkifarindo Duta is classified as still manual, where there is not yet a system for selecting quality migrant workers so it requires a long time for its assessment and the selection process is less effective. To support decision making in the selection of qualified Indonesian Workers (TKI) to make it easier by using a decision support system. One method used in the selection of qualified Indonesian Workers is the Profile Matching method. The profile matching method is a decision-making mechanism by assuming that there is an ideal level of predictor variables that must be met by applicants, rather than the minimum level that must be met or passed. In the profile matching process a process will be compared between individual competencies into standard competencies so that different competencies can be identified (also called Gap). The smaller the gap produced, the greater the weight value. In matching this profile, the selected TKI candidates are Indonesian Workers who are closest to the ideal profile of a qualified TKI.


2007 ◽  
Vol 15 (3) ◽  
pp. 346-353 ◽  
Author(s):  
P Patrizio ◽  
E Fragouli ◽  
V Bianchi ◽  
A Borini ◽  
D Wells

2001 ◽  
Vol 24 (4) ◽  
pp. 629-640 ◽  
Author(s):  
Joshua B. Tenenbaum ◽  
Thomas L. Griffiths

Shepard has argued that a universal law should govern generalization across different domains of perception and cognition, as well as across organisms from different species or even different planets. Starting with some basic assumptions about natural kinds, he derived an exponential decay function as the form of the universal generalization gradient, which accords strikingly well with a wide range of empirical data. However, his original formulation applied only to the ideal case of generalization from a single encountered stimulus to a single novel stimulus, and for stimuli that can be represented as points in a continuous metric psychological space. Here we recast Shepard's theory in a more general Bayesian framework and show how this naturally extends his approach to the more realistic situation of generalizing from multiple consequential stimuli with arbitrary representational structure. Our framework also subsumes a version of Tversky's set-theoretic model of similarity, which is conventionally thought of as the primary alternative to Shepard's continuous metric space model of similarity and generalization. This unification allows us not only to draw deep parallels between the set-theoretic and spatial approaches, but also to significantly advance the explanatory power of set-theoretic models.


Author(s):  
Levy O’Flynn.

Referendums are now common in ‘conflict societies’—societies where a widespread and concerted campaign of violence between groups recently occurred, is occurring, or is liable to occur. In the ideal case, a peace referendum can secure consent for a new formal peace settlement among warring groups and provide the settlement with a popular mandate. In practice, however, settlements, once attained, may struggle to endure. Some may collapse entirely. Against this background we introduced what we call the ‘Deliberative Peace Referendum’, or ‘DPR’. A DPR is a purpose-designed deliberative referendum held under conditions of conflict. As this chapter recognizes, designing a referendum to be more deliberative is a challenge under any circumstances. It may be hardest of all amid armed intercommunal conflict.


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