An apparatus for the instantaneous measurement of the relative light intensity

1968 ◽  
Vol 11 ◽  
Author(s):  
G. Vyncke ◽  
R. Goossens

An  apparatus for the instantaneous measurement of the relative light intensity  was constructed by Brechtel (1962). An analogical apparatus was built, from  the same point of view, but on another principle. Namely two selenium  photo-cells, connected in opposition, produce anti-currents in a closed  circuit. The differential current is compensated or reduced to zero by a  linear potentiometer.     The position of this potentiometer can be related to a value for the  relative ratio between the light intensity above and below the forest canopy.  The neutral density filters, which are necessary for the used photo-cells,  can enlarge the reading scale, if they are chosen judiciously.     Some positive measurements were done in a forest stand. Generally the  apparatus will give good results and will be easily used for the  characterization of light condition in forest stands.

2020 ◽  
Vol 4 (2) ◽  
pp. 118-129
Author(s):  
Asti Gumartifa ◽  
◽  
Indah Windra Dwie Agustiani

Gaining English language learning effectively has been discussed all years long. Similarly, Learners have various troubles outcomes in the learning process. Creating a joyful and comfortable situation must be considered by learners. Thus, the implementation of effective learning strategies is certainly necessary for English learners. This descriptive study has two purposes: first, to introduce the classification and characterization of learning strategies such as; memory, cognitive, metacognitive, compensation, social, and affective strategies that are used by learners in the classroom and second, it provides some questionnaires item based on Strategy of Inventory for Language Learning (SILL) version 5.0 that can be used to examine the frequency of students’ learning strategies in the learning process. The summary of this study explains and discusses the researchers’ point of view on the impact of learning outcomes by learning strategies used. Finally, utilizing appropriate learning strategies are certainly beneficial for both teachers and learners to achieve the learning target effectively.


2005 ◽  
Vol 156 (12) ◽  
pp. 481-486 ◽  
Author(s):  
Jurij Diaci ◽  
Lahorka Kozjek

The objective of our research was to examine the effect of canopy shading on beech sapling architecture in the oldgrowth silver fir-beech forests of Pecka and Rajhenavski Rog. In August 2003 we sampled one plot (352 m2) in a large gap in Pecka, which was a result of a strong windstorm in 1983, and eight small gaps (26–78 m2) with similar sapling heights (3.8–8 m). A ground view of each gap was drawn including the characteristics of gap border trees and the density of separate sapling layers was recorded. The height and diameter were measured for each sapling, as well as the following quality characteristics on selected dominant saplings: width of the crown,number of larger branches and knots (>1/3 DBH), intensity of stem bending, deviation from vertical growth, number of terminal shoots, and the type of damage. The results show a negative effect of high canopy shading (estimated relative light intensity was below 5%) on the architectural quality of saplings. A lower overall density of saplings, greater intensity of bending and deviation from vertical growth, a shorter stem length without branches, a larger number of saplings with two terminal shoots, and a larger number of damaged saplings were observed in small gaps.


Keyword(s):  

The article discusses a sequence of activities to identify a crime as jointly committed. The requirements to the algorithm of such activities are formulated. Programme-based and targeted methods applied by the authors allowed detecting a range of stages of the algorithm. The first four stages aim at defining mandatory elements of a crime allowing to characterize it as a jointly committed action. The rest of the stages focus on identifying a type of criminal complicity. In the article, each stage is described. It is emphasized that in each stage there is a special objective. At the same time, all these stages, taken together, constitute a separate module of the program of criminal characterization of an action. From the authors’ point of view, algorithms are necessary not only for detection of crimes and their criminal characterization, but also for answering the question on existence of criminal complicity in each case. Also the authors give their opinions on interpretation of criminal complicity as a legal category. In particular, it is emphasized that not all of crimes merely committed with participation of two or more persons should be understood as jointly committed. It is joint participation that makes a crime jointly committed. Various forms of criminal complicity and types of co-offenders are considered in the article as well. In various crimes, criminal complicity manifests itself differently. Therefore the proposed algorithm can be applied only after identification a specific article of the Russian Criminal Code stipulating the responsibility for the crime committed.


Fractals ◽  
2020 ◽  
Vol 28 (02) ◽  
pp. 2050050
Author(s):  
V. E. ARCE-GUEVARA ◽  
M. O. MENDEZ ◽  
J. S. MURGUÍA ◽  
A. ALBA ◽  
H. GONZÁLEZ-AGUILAR ◽  
...  

In this work, the scaling behavior of the sleep process is evaluated by using detrended fluctuation analysis based on wavelets. The analysis is carried out from arrivals of short and recurrent cortical events called A-phases, which in turn build up the Cyclic Alternating Pattern phenomenon, and are classified in three types: A1, A2 and A3. In this study, 61 sleep recordings corresponding to healthy, nocturnal frontal lobe epilepsy patients and sleep-state misperception subjects, were analyzed. From the A-phase annotations, the onsets were extracted and a binary sequence with one second resolution was generated. An item in the sequence has a value of one if an A-phase onset occurs in the corresponding window, and a value of zero otherwise. In addition, we consider other different temporal resolutions from 2[Formula: see text]s to 256[Formula: see text]s. Furthermore, the same analysis was carried out for sequences obtained from the different types of A-phases and their combinations. The results of the numerical analysis showed a relationship between the time resolutions and the scaling exponents; specifically, for higher time resolutions a white noise behavior is observed, whereas for lower time resolutions a behavior towards to [Formula: see text]-noise is exhibited. Statistical differences among groups were observed by applying various wavelet functions from the Daubechies family and choosing the appropriate sequence of A-phase onsets. This scaling analysis allows the characterization of the free-scale dynamic of the sleep process that is specific for each sleep condition. The scaling exponent could be useful as a diagnosis parameter in clinics when sleep macrostructure does not offer enough information.


Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1550
Author(s):  
Dominic Greiffenberg ◽  
Marie Andrä ◽  
Rebecca Barten ◽  
Anna Bergamaschi ◽  
Martin Brückner ◽  
...  

Chromium compensated GaAs or GaAs:Cr sensors provided by the Tomsk State University (Russia) were characterized using the low noise, charge integrating readout chip JUNGFRAU with a pixel pitch of 75 × 75 µm2 regarding its application as an X-ray detector at synchrotrons sources or FELs. Sensor properties such as dark current, resistivity, noise performance, spectral resolution capability and charge transport properties were measured and compared with results from a previous batch of GaAs:Cr sensors which were produced from wafers obtained from a different supplier. The properties of the sample from the later batch of sensors from 2017 show a resistivity of 1.69 × 109 Ω/cm, which is 47% higher compared to the previous batch from 2016. Moreover, its noise performance is 14% lower with a value of (101.65 ± 0.04) e− ENC and the resolution of a monochromatic 60 keV photo peak is significantly improved by 38% to a FWHM of 4.3%. Likely, this is due to improvements in charge collection, lower noise, and more homogeneous effective pixel size. In a previous work, a hole lifetime of 1.4 ns for GaAs:Cr sensors was determined for the sensors of the 2016 sensor batch, explaining the so-called “crater effect” which describes the occurrence of negative signals in the pixels around a pixel with a photon hit due to the missing hole contribution to the overall signal causing an incomplete signal induction. In this publication, the “crater effect” is further elaborated by measuring GaAs:Cr sensors using the sensors from 2017. The hole lifetime of these sensors was 2.5 ns. A focused photon beam was used to illuminate well defined positions along the pixels in order to corroborate the findings from the previous work and to further characterize the consequences of the “crater effect” on the detector operation.


Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1304
Author(s):  
Francisco Espínola ◽  
Alfonso M. Vidal ◽  
Juan M. Espínola ◽  
Manuel Moya

Wild olive trees have important potential, but, to date, the oil from wild olives has not been studied significantly, especially from an analytical point of view. In Spain, the wild olive tree is called “Acebuche” and its fruit “Acebuchina”. The objective of this work is to optimize the olive oil production process from the Acebuchina cultivar and characterize the oil, which could be marketed as healthy and functional food. A Box–Behnken experimental design with five central points was used, along with the Response Surface Methodology to obtain a mathematical experimental model. The oils from the Acebuchina cultivar meet the requirements for human consumption and have a good balance of fatty acids. In addition, the oils are rich in antioxidants and volatile compounds. The highest extraction yield, 12.0 g oil/100 g paste, was obtained at 90.0 min and the highest yield of phenolic compounds, 870.0 mg/kg, was achieved at 40.0 °C, and 90.0 min; but the maximum content of volatile compounds, 26.9 mg/kg, was obtained at 20 °C and 30.0 min. The oil yield is lower than that of commercial cultivars, but the contents of volatile and phenolic compounds is higher.


Morphology ◽  
2021 ◽  
Author(s):  
Rossella Varvara ◽  
Gabriella Lapesa ◽  
Sebastian Padó

AbstractWe present the results of a large-scale corpus-based comparison of two German event nominalization patterns: deverbal nouns in -ung (e.g., die Evaluierung, ‘the evaluation’) and nominal infinitives (e.g., das Evaluieren, ‘the evaluating’). Among the many available event nominalization patterns for German, we selected these two because they are both highly productive and challenging from the semantic point of view. Both patterns are known to keep a tight relation with the event denoted by the base verb, but with different nuances. Our study targets a better understanding of the differences in their semantic import.The key notion of our comparison is that of semantic transparency, and we propose a usage-based characterization of the relationship between derived nominals and their bases. Using methods from distributional semantics, we bring to bear two concrete measures of transparency which highlight different nuances: the first one, cosine, detects nominalizations which are semantically similar to their bases; the second one, distributional inclusion, detects nominalizations which are used in a subset of the contexts of the base verb. We find that only the inclusion measure helps in characterizing the difference between the two types of nominalizations, in relation with the traditionally considered variable of relative frequency (Hay, 2001). Finally, the distributional analysis allows us to frame our comparison in the broader coordinates of the inflection vs. derivation cline.


Author(s):  
Nilkanth Laxman Pal ◽  
Ambika Sumeet Juwarkar ◽  
Sanjaya Viswamitra

Abstract Background Encephaloceles refer to the herniation of intracranial contents through the defect in the dura and calvarium. This article aims to equip the radiologists with all the necessary information to approach a case of encephalocele in a systematic manner and report in an organized format. Thus reduce the reporting time without overlooking any detail. Main text An extensive literature review was performed searching through the standard textbooks and electronic databases to obtain thorough information on the various encephaloceles particularly from a radiological point of view. The author’s observations were also incorporated in the review. Among the available imaging modalities, magnetic resonance imaging is the most versatile and considered the imaging modality of choice because of superior anatomic resolution in the characterization of central nervous system malformation. This study provides the reporting radiologist with a methodical guide to approach a case of encephalocele discussing the imaging protocol, relevant anatomy, classification, associated abnormalities, and imaging prognostic factors. Conclusion Encephalocele has always been a subject of predicament for radiologists. Understanding the relevant terminologies, anatomy, imaging protocols, classification, associated malformations/anomalies, and imaging prognostic factors will help to methodically approach each case and provide a systematic and comprehensive report.


1968 ◽  
Vol 1 (8) ◽  
pp. T.129-T.132 ◽  
Author(s):  
F. M. Toates

The reciprocal interaction between the accommodation and pupil control systems of the human eye is examined from a theoretical point of view. The system, which is responsible for maintaining pupil diameter at a value which is a compromise between conflicting requirements, is represented by a control model, and is considered in terms of the concept of a performance index.


MRS Advances ◽  
2019 ◽  
Vol 4 (64) ◽  
pp. 3579-3585
Author(s):  
Guillermo M. González Guerra ◽  
Alejandro Alatorre-Ordaz ◽  
Gerardo González Garcia ◽  
Jesus S. Jaime-Ferrer

ABSTRACTThis work presents the synthesis and characterization of a pearylated polysiloxane material (PAP) from a polycondensation reaction, followed by functionalization with HClSO3 by an electrophilic substitution reaction. According to the characterization techniques applied, a sulfonated pearylated polysiloxane was also obtained, (SPAP). The purpose of this sulfonated material is to obtain an ionomer able to be applied in hydrogen fuel cells of the proton exchange membrane kind (PEMFC). The reaction to produce the polysiloxane precursor was carried out with the commercial reagents: PhSiCl3, Ph2SiCl2 and Ph3SiCl in anhydrous THF at 75 °C and the SPAP material was obtained by sulfonation of the precursor with chlorosulfonic acid. PAP and SPAP were characterized by 1H, NMR for liquids, 29Si NMR for solids, IR-ATR, SEM, and cyclic voltammetry. The NMR 29Si spectra show that PAP and PAPS contain crosslinking regions due to PhSiCl3, growing chain zones due to Ph2SiCl2 and polymer termination zones due to Ph3SiCl, obtaining a mixture of siloxanes. The analysis by cyclic voltammetry indicates that by integrating the area under the curve of the adsorption peaks of H2, a value of 0.062 mC/cm2 is obtained, a value close to the commercial ionomer of Nafion®.


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