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Possible crater-based pingos, paleolakes and periglacial landscapes in the high latitudes of Utopia Planitia, Mars
THE INFLUENCE OF FOLIAR FERTILIZATION WITH HUMIC ACIDS ON THE PRODUCTION OF WHITE CABBAGE
The main purpose of the study was to test the effect of some fertilizers based on humic acids on autumn cabbage,Bucharest F1 in the ecological conditions of the South-West of Romania. The foliar products applied were formulated and obtained by ICPA Bucharest. The biological material was represented by the Bucharest F1 hybrid. The experience included three variants: V1-untreated, V2-foliar fertilization with Deceneu and V3 foliar fertilization with Humifert Plus. In order to achieve the proposed objectives, biometric determinations have been carried out on the eatable organs: height and diameter of the head, the shape index and the degree of stuffi,but also the quantity and quality of the cabbage production. Application of fertilizers led to increased production at the fertilized variants, significant differences were at the variant with the Deceneu product, 132.5 kg/ha and a good accumulation of ascorbic acid, 35.78 mg/100g fresh matter, when applying Humifert Plu
Setting up a PDPA system for measurements in a Diesel spray
Abstract.
A PDPA system was set up, optimised and used to measure the time resolved characteristics of the droplets inside a spray produced by a common-rail diesel fuel injection system. Some preliminary tests are performed with gas flows to optimise the optical set-up. Parametric studies are performed to gain an understanding of the particle density limits of the system, and their dependence on PDPA system parameters. Then the diesel spray produced by a single-hole injector is measured, with the fuel pressure ranging from 500 to 1300 bar, gas density in the test chamber ranging from ambient conditions to 40 kg/m3. Fuel and gas temperature were 25ÂșC. Beam waist size is reduced to the minimum value allowed by the optical stand-off of the spray enclosure. Receiver lens focal length is similarly reduced. Receiver slit width, which is found to have a dramatic effect on the detection of droplets during the injection period, was tested in the range from 100um to 25um. Tests performed with two different slit heights are tested, respectively 1mm and 50 ÎŒm, show that this parameter has minimal effect on performance. PMT voltage (gain) is held to a moderately low value between 400 and 500 volt and the laser power between 400 and 800 mW in the green line. Optimum burst threshold is found to obtain the best quality data regardless of background level, which varies greatly in high-density pulsed sprays
Degree spectra for transcendence in fields
We show that for both the unary relation of transcendence and the finitary
relation of algebraic independence on a field, the degree spectra of these
relations may consist of any single computably enumerable Turing degree, or of
those c.e. degrees above an arbitrary fixed degree. In other
cases, these spectra may be characterized by the ability to enumerate an
arbitrary set. This is the first proof that a computable field can
fail to have a computable copy with a computable transcendence basis
Possible polyphase periglaciation and glaciation adjacent to the Moreux impact-crater, Mars
International audienceThe cyclicity and temporal succession of glacial-periglacial periods or epochs are keynotes of cold-climate geology on Earth. Relatively recent work within the Mars community has begun to dissect the mid- to higher-latitudinal terrain of Mars for analogical evidence of similar cold-climate cyclicity and succession.Here, we carry on with this work by focusing on the terrain immediately to the north of the Moreux impact-crater (40â44° N, 43â47° E). The crater is located in northern Arabia Terra, to the south of Protonilus Mensae. It lies astride of and postdates Mars' crustal-dichotomy. The latter is a global geological-boundary that separates the ancient southern-highlands from the relatively younger northern-lowland plains.Using cross-cutting relationships, relative stratigraphy and crater-size frequency distributions (CSFDs) we identify three glacial and two periglacial periods that are temporally intertwined and differentiated by a suite of features unique to each of these periods. For example, we report and discuss clusters of pingo-like mounds amidst ridge and trough terrain or âbrain terrainâ. On Earth, the former are the work of freeze-thaw cycling; on Mars, the latter are thought to be glacial remnants. In turn, the brain terrain is underlain by small-sized polygons possibly formed by thermal contraction cracking and with margins underlain by degraded ice-wedges. Age estimates derived of CSFDs suggest that the polygonised terrain could as much as ~100 Ma, whereas the brain terrain and pingo-like mounds are thought to be ~1â~10 Ma. Possible terminal-moraines that intercept brain-terrain fragments point to an even more recent period of glaciation.If the CSFD age-estimates are valid, then the polygons that underlie the brain terrain and incise the basin floors of our study zone could be an order of magnitude older than most of the age estimates associated with polygonised terrain at other locations on Mars. The fact that there are two distinct periods of polygonization and periglacial activity with a wide offset of time within one relatively small study zone also highlights the extent to which the freeze-thaw cycling of water might be rooted as iteratively and as deeply in Mars' geological history as is its glaciation
Understanding the strategic implications of the weaponization of Artificial Intelligence
Artificial Intelligence (AI) is expected to have a revolutionary impact across societies and to create economic displacement and disruption in security and defense. Yet the impact of AI on national security and military affairs has received relatively scant attention. The existing policy-focused literature has concentrated mainly on the technological, ethical or legal limitations of deploying AI and on the risks associated with it. This paper seeks to contribute to the debate by outlining the strategic implications of the weaponization of AI for international security. It explores how and in what ways AI is currently being utilized in the defense sector to enhance offensive and defensive military technologies and operations and assesses the ways in which the incorporation of AI into military platforms will affect war fighting and strategic decision-making. The paper is in four sections. Section one develops a typology of military AI that forms a foundation for the rest of the paper. The second section examines the uses of AI in cyberspace and the relationships between âcyber weaponsâ and AI capabilities. The third section examines how the embeddedness of AI-based capabilities across the land, air, naval and space domains may affect combined arms operations. The final section distills the main strategic implications of weaponized AI, which include the speed of decision-making and action as well as enhanced domain situational awareness
Analyzing program analyses
We want to prove that a static analysis of a given program is complete, namely, no imprecision arises when asking some query on the program behavior in the concrete (i.e., for its concrete semantics) or in the abstract (i.e., for its abstract interpretation). Completeness proofs are therefore useful to assign confidence to alarms raised by static analyses. We introduce the completeness class of an abstraction as the set of all programs for which the abstraction is complete. Our first result shows that for any nontrivial abstraction, its completeness class is not recursively enumerable. We then introduce a stratified deductive system a2A to prove the completeness of program analyses over an abstract domain A. We prove the soundness of the deductive system. We observe that the only sources of incompleteness are assignments and Boolean tests \u2014 unlikely a common belief in static analysis, joins do not induce incompleteness. The first layer of this proof system is generic, abstraction-agnostic, and it deals with the standard constructs for program composition, that is, sequential composition, branching and guarded iteration. The second layer is instead abstraction-specific: the designer of an abstract domain A provides conditions for completeness in A of assignments and Boolean tests which have to be checked by a suitable static analysis or assumed in the completeness proof as hypotheses. We instantiate the second layer of this proof system first with a generic nonrelational abstraction in order to provide a sound rule for the completeness of assignments. Orthogonally, we instantiate it to the numerical abstract domains of Intervals and Octagons, providing necessary and sufficient conditions for the completeness of their Boolean tests and of assignments for Octagons
Clastic patterned ground in Lomonosov crater, Mars: examining fracture controlled formation mechanisms
The area surrounding Lomonosov crater on Mars has a high density of seemingly organised boulder patterns. These form seemingly sorted polygons and stripes within kilometre scale blockfields, patches of boulder strewn ground which are common across the Martian high latitudes. Several hypotheses have been suggested to explain the formation of clastic patterned ground on Mars. It has been proposed that these structures could have formed through freeze-thaw sorting, or conversely by the interaction of boulders with underlying fracture polygons.
In this investigation a series of sites were examined to evaluate whether boulder patterns appear to be controlled by the distribution of underlying fractures and test the fracture control hypotheses for their formation. It was decided to focus on this suite of mechanisms as they are characterised by a clear morphological relationship, namely the presence of an underlying fracture network which can easily be evaluated over a large area.
It was found that in the majority of examples at these sites did not exhibit fracture control. Although fractures were present at many sites there were very few sites where the fracture network appeared to be controlling the boulder distribution. In general these were not the sites with the best examples of organization, suggesting that the fracture control mechanisms are not the dominant geomorphic process organising the boulders in this area
THE EFFECT OF ORGANIC FERTILIZATION ON FRUIT PRODUCTION AND QUALITY OF TOMATOES GROWN IN THE SOLAR
The purpose of this study was to observe the effect of organic fertilization on the production and quality of tomato fruits grown in early culture in the solar. The influence of this fertilizer was followed in 2017 in a tomato crop in southwestern Romania (AlmÄj-Dolj). The Reyana hybrid was studied which was foliarly fertilized with the organic product Folicist in the doses of 0.5 l/ha, 1.0 l/ha and 1.5 l/ha. The parameters traced were: production, humidity, soluble dry substance, titratable acidity, vitamin C content, total polyphenols and carotenes as well as fruit pH. The highest yield of 12.76 t/ha was obtained at a dose of 1.0 l/ha and also at the same dose were recorded the best quality parameters of the fruit, such as: S.D.S. was 4.7 oBx, humidity of 90.3%, titre acidity of 1.33 mg/NaOH/100g f.m., vitamin C of 24.3 mg/100g f.m., total polyphenols 66.4 mg/100g f.m., total carotenes 51.3 mg/100g f.m. and pH 4.49.ĂÂ These results show that an adequate fertilization of plants with nutrients substances is crucial to achieving high yields and good-tasting fruits.Ă
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