positive region
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2021 ◽  
Author(s):  
Yingjie Zhu ◽  
Bin Yang

Abstract Hierarchical structured data are very common for data mining and other tasks in real-life world. How to select the optimal scale combination from a multi-scale decision table is critical for subsequent tasks. At present, the models for calculating the optimal scale combination mainly include lattice model, complement model and stepwise optimal scale selection model, which are mainly based on consistent multi-scale decision tables. The optimal scale selection model for inconsistent multi-scale decision tables has not been given. Based on this, firstly, this paper introduces the concept of complement and lattice model proposed by Li and Hu. Secondly, based on the concept of positive region consistency of inconsistent multi-scale decision tables, the paper proposes complement model and lattice model based on positive region consistent and gives the algorithm. Finally, some numerical experiments are employed to verify that the model has the same properties in processing inconsistent multi-scale decision tables as the complement model and lattice model in processing consistent multi-scale decision tables. And for the consistent multi-scale decision table, the same results can be obtained by using the model based on positive region consistent. However, the lattice model based on positive region consistent is more time-consuming and costly. The model proposed in this paper provides a new theoretical method for the optimal scale combination selection of the inconsistent multi-scale decision table.


2021 ◽  
Author(s):  
Heather S. Bruce ◽  
Nipam H. Patel

SummaryUnderstanding how novel structures arise is a central question in evolution. The carapace of the waterflea Daphnia is a bivalved “cape” of exoskeleton that has been proposed to be one of many novel arthropod structures that arose through repeated co-option of genes that also pattern insect wings1–3. To determine whether the Daphnia carapace is a novel structure, we compare the expression of pannier, araucan, and vestigial between Daphnia, Parhyale, and Tribolium. Our results suggest that the Daphnia carapace did not arise by co-option, but instead derives from an ancestral exite (lateral lobe) that emerges from a proximal leg segment that was incorporated into the Daphnia body wall. The Daphnia carapace therefore appears to be homologous to the Parhyale tergal plate and the insect wing4. Remarkably, the vestigial-positive region that gives rise to the Daphnia carapace appears to be present in Parhyale5 and Tribolium as a small, inconspicuous protrusion. Similarly, the vestigial-positive developmental fields that form tergal plates in Parhyale appear to be present in Daphnia, even though Daphnia does not form tergal plates. Thus, rather than a novel structure resulting from gene co-option, the Daphnia carapace appears to have arisen from a shared, ancestral developmental field that persists in a cryptic state in other arthropod lineages. Cryptic persistence of unrecognized serially homologous developmental fields may thus be a general solution for the origin of novel structures. Our simple molecular triangulation strategy, which does not require functional studies, can illuminate the homologies of long-debated structures on the legs and body wall of arthropods.


2021 ◽  
pp. 107253
Author(s):  
Xiaojun Xie ◽  
Xingjian Gu ◽  
Yanbin Li ◽  
Zhiwei Ji

Author(s):  
Iskandar B. Khakimov ◽  
Firuz A. Rakhimov ◽  
Izatullo N. Ganiev ◽  
Ziyodullo R. Obidov

The article presents the results of the study of the oxidation kinetics and the anodic behavior of the zinc-aluminum alloy Zn22Al, doped with nickel, in various corrosive environments. The kinetic and energy parameters of the process of high-temperature oxidation of alloys are determined. It is shown that the process of high-temperature oxidation of samples of Zn22Al-Ni alloys is characterized by a monotonic decrease in the true oxidation rate and an increase in the effective activation energy at the content of the alloying component in the initial Zn0.5Al alloy up to 0.5 wt.%. It was found that nickel additives within the studied concentration (0.01-0.5 wt.% ) slightly increases the oxidability of the base alloy Zn22Al at temperatures of 523, 573 and 623 K. It is shown that the dependence of the corrosion potential of zinc-aluminum alloys on the nickel content in them is of the same type, i.e. the additives of the alloying component contribute to the displacement of the corrosion potential in the region of positive values. The influence of the aggressiveness of the corrosive medium on the anodic behavior of alloys when comparing concentrated electrolytes with the increasing concentration of chloride ions in the sodium chloride solution is established. It is determined that the potentials of pitting formation and repassivation of the initial alloys shift to a more positive region with an increase in the nickel concentration in the alloys. The greatest shift of these potentials to the positive region is observed when alloying alloys containing small nickel additives. It is shown that the corrosion products of the studied alloys consist of a mixture of protective oxide films Al2O3, ZnO, NiO, Al2O3·ZnO and Al2O3·Ni2O3. It was found that the alloying of zinc-aluminum alloys with nickel (in the range of 0.01–0.05 wt.%) reduces the corrosion rate of the base alloy by 2-3 times. The proposed alloy compositions can be used as an anode coating for corrosion protection of steel products and structures.


Author(s):  
Chengfeng Long ◽  
Xingxin Liu ◽  
Yakun Yang ◽  
Tao Zhang ◽  
Siqiao Tan ◽  
...  

AbstractConsidering the issue with respect to the high data redundancy and high cost of information collection in wireless sensor nodes, this paper proposes a data fusion method based on belief structure to reduce attribution in multi-granulation rough set. By introducing belief structure, attribute reduction is carried out for multi-granulation rough sets. From the view of granular computing, this paper studies the evidential characteristics of incomplete multi-granulation ordered information systems. On this basis, the positive region reduction, belief reduction and plausibility reduction are put forward in incomplete multi-granulation ordered information system and analyze the consistency in the same level and transitivity in different levels. The positive region reduction and belief reduction are equivalent, and the positive region reduction and belief reduction are unnecessary and sufficient conditional plausibility reduction in the same level, if the cover structure order of different levels are the same the corresponding equivalent positive region reduction. The algorithm proposed in this paper not only performs three reductions, but also reduces the time complexity largely. The above study fuses the node data which reduces the amount of data that needs to be transmitted and effectively improves the information processing efficiency.


Author(s):  
Heather Bruce

Understanding how novel structures arise is a central question in evolution. The carapace of the waterflea Daphnia is a bivalved “cape” of exoskeleton that surrounds the animal, and has been proposed to be one of many novel structures that arose through repeated co-option of genes that also pattern insect wings. To determine whether the Daphnia carapace is a novel structure, the expression of pannier, the Iroquois gene aurucan, and vestigial are compared between Daphnia, Parhyale, and Tribolium. The results suggest that the Daphnia carapace did not arise by cooption, but instead represents an elongated ancestral exite (lateral lobe or plate) that emerges from a proximal leg segment that was incorporated into the Daphnia body wall. The Daphnia carapace therefore appears to be homologous to the Parhyale tergal plate and the insect wing. In addition, the vg-positive region that gives rise to the Daphnia carapace also appears to be present in Parhyale and Tribolium, which do not form a carapace. Thus, rather than a novel structure resulting from gene co-option, the carapace appears to have arisen from an ancient, conserved developmental field that persists in a cryptic state in other arthropod lineages, but in Daphnia became elaborated into the carapace. Cryptic persistence of serially homologous developmental fields may thus be a general solution for the origin of many novel structures.


Author(s):  
Heather Bruce

Understanding how novel structures arise is a central question in evolution. The carapace of the waterflea Daphnia is a bivalved “cape” of exoskeleton that surrounds the animal, and has been proposed to be one of many novel structures that arose through repeated co-option of genes that also pattern insect wings. To determine whether the Daphnia carapace is a novel structure, the expression of pannier, the Iroquois gene aurucan, and vestigial are compared between Daphnia, Parhyale, and Tribolium. The results suggest that the Daphnia carapace did not arise by cooption, but instead represents an elongated ancestral exite (lateral lobe or plate) that emerges from a proximal leg segment that was incorporated into the Daphnia body wall. The Daphnia carapace therefore appears to be homologous to the Parhyale tergal plate and the insect wing. In addition, the vg-positive region that gives rise to the Daphnia carapace also appears to be present in Parhyale and Tribolium, which do not form a carapace. Thus, rather than a novel structure resulting from gene co-option, the carapace appears to have arisen from an ancient, conserved developmental field that persists in a cryptic state in other arthropod lineages, but in Daphnia became elaborated into the carapace. Cryptic persistence of serially homologous developmental fields may thus be a general solution for the origin of many novel structures.


2020 ◽  
Author(s):  
Chenfeng Long ◽  
Xinxing Liu ◽  
Yakun Yang ◽  
Tao Zhang ◽  
Siqiao Tan ◽  
...  

Abstract Considering the issue with respect to the high data redundancy and high cost of information collection in wireless sensor nodes, this paper proposes a data fusion method based on belief structure to reduce attribution in multi-granulation rough set. By introducing belief structure, attribute reduction is carried out for multi-granulation rough sets. From the view of granular computing, this paper studies the evidential characteristics of incomplete multi-granulation ordered information systems. On this basis, the positive region reduction, belief reduction and plausibility reduction are put forward in incomplete multi-granulation order information system, and analyze the consistency in the same level and transitivity in different levels. The positive region reduction and belief reduction are equivalent, and the positive region reduction and belief reduction is unnecessary and sufficient conditional plausibility reduction in the same level; if the cover structure order of different levels are the same, the corresponding equivalent positive region reduction. The algorithm proposed in this paper not only performs three reductions, but also reduces the time complexity largely. The above study fuses the node data which reduces the amount of data that needs to be transmitted and effectively improves the information processing efficiency.


Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4495
Author(s):  
Steve Scheiner

Several cyano groups are added to an alkane, alkene, and alkyne group so as to construct a Lewis acid molecule with a positive region of electrostatic potential in the area adjoining these substituents. Although each individual cyano group produces only a weak π-hole, when two or more such groups are properly situated, they can pool their π-holes into one much more intense positive region that is located midway between them. A NH3 base is attracted to this site, where it forms a strong noncovalent bond to the Lewis acid, amounting to as much as 13.6 kcal/mol. The precise nature of the bonding varies a bit from one complex to the next but typically contains a tetrel bond to the C atoms of the cyano groups or the C atoms of the linkage connecting the C≡N substituents. The placement of the cyano groups on a cyclic system like cyclopropane or cyclobutane has a mild weakening effect upon the binding. Although F is comparable to C≡N in terms of electron-withdrawing power, the replacement of cyano by F substituents substantially weakens the binding with NH3.


Symmetry ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1189 ◽  
Author(s):  
Linzi Yin ◽  
Zhaohui Jiang

Attribute reduction is one of the challenging problems in rough set theory. To accomplish an efficient reduction algorithm, this paper analyzes the shortcomings of the traditional methods based on attribute significance, and suggests a novel reduction way where the traditional attribute significance calculation is replaced by a special core attribute calculation. A decision table called the positive region sort ascending decision table (PR-SADT) is defined to optimize some key steps of the novel reduction method, including the special core attribute calculation, positive region calculation, etc. On this basis, a fast reduction algorithm is presented to obtain a complete positive region reduct. Experimental tests demonstrate that the novel reduction algorithm achieves obviously high computational efficiency.


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