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51.
Muhammet Usak Milan Kubiatko Muhammad Salman Shabbir Olesya Viktorovna Dudnik Kittisak Jermsittiparsert Lila Rajabion 《International Journal of Communication Systems》2020,33(2)
Today, the Internet of Things (IoT) becomes a heterogeneous and highly distributed structure which can respond to the daily needs of people and different organizations. With the fast development of IT‐based technologies such as IoT and cloud computing, low‐cost health services and their support, efficient supervision of the centralized management, and monitoring of public health can be realized. Therefore, there has been increasing attention in the integration of IoT and health care both in academic and the business world. However, while the health care service industry fully holds the welfares of information systems for its personnel and patients, there is a need for an improved understanding of the issues and opportunities related to IoT‐based health care systems. But, as far as we know, the detailed review and deep discussion in this field are very rare. Hence, in this paper, we presented a literature review on the IoT‐based health care services from papers published until 2018. Moreover, the drawbacks and benefits of the reviewed mechanisms have been discussed, and the main challenges of these mechanisms are highlighted for developing more efficient IoT techniques over health care services in the future. The results of this paper will be valuable for both practitioners and academicians, and it can provide visions into future research areas in this domain. By providing comparative information and analyzing the current developments in this area, this paper will directly support academics and working professionals for better knowing the progress in IoT mechanisms. As a general result, we found that IoT could help the governments to improve health services in society and commercial interactions. 相似文献
52.
Synthesis and field bioassay of some analogs of sex pheromone of citrus mealybug,Planococcus citri (Risso) 总被引:1,自引:0,他引:1
Ezra Dunkelblum Yair Ben-Dov Zeev Goldschmidt Joel L. Wolk Lila Somekh 《Journal of chemical ecology》1987,13(4):863-871
A series of structural analogs of (s+)-cis-(1R)-3-isopropenyl-2,2-dimethylcyclobutanemethanol acetate, sex pheromone of the citrus mealybug,Planococcus citri (Risso), was synthesized. The analogs were tested in a field bioassay in order to determine the structure-activity relationships of the pheromone. All changes in structure reduced the activity of the test compounds, to various degrees. The most active analog tested was the homolog (+)-cis-(1R)-3-isopropenyl-2,2-dimethylcyclobutaneethanol acetate (IV), whose activity, at a higher dosage, was comparable to that of the pheromone. The alcohol (+)-cis-(1R)-3-isopropenyl-2,2-dimethylcyclobutanemethanol was tested in mixtures with the pheromone and found to be neither an inhibitor nor a Synergist. The results show that all functional groups of the pheromone molecule are essential for optimal biological activity.Homoptera: Coccoidea: Pseudococcidae.Contribution from the Agricultural Research Organization (ARO), The Volcani Center, Bet Dagan, Israel, No. 1667-E, 1986 series.Levi Eshkol Postdoctoral Fellow, 1984–1986. 相似文献
53.
Alejandro Osorio-Forero Najma Cherrad Lila Banterle Laura M. J. Fernandez Anita Lüthi 《International journal of molecular sciences》2022,23(9)
For decades, numerous seminal studies have built our understanding of the locus coeruleus (LC), the vertebrate brain’s principal noradrenergic system. Containing a numerically small but broadly efferent cell population, the LC provides brain-wide noradrenergic modulation that optimizes network function in the context of attentive and flexible interaction with the sensory environment. This review turns attention to the LC’s roles during sleep. We show that these roles go beyond down-scaled versions of the ones in wakefulness. Novel dynamic assessments of noradrenaline signaling and LC activity uncover a rich diversity of activity patterns that establish the LC as an integral portion of sleep regulation and function. The LC could be involved in beneficial functions for the sleeping brain, and even minute alterations in its functionality may prove quintessential in sleep disorders. 相似文献
54.
Eliseo Sarmiento Maria Vaz Pinto Rafael H. Villarreal 《Applicable Algebra in Engineering, Communication and Computing》2011,22(4):249-264
Let X be a subset of a projective space, over a finite field K, which is parameterized by the monomials arising from the edges of a clutter. Let I(X) be the vanishing ideal of X. It is shown that I(X) is a complete intersection if and only if X is a projective torus. In this case we determine the minimum distance of any parameterized linear code arising from X. 相似文献
55.
C. Escobar M. Villarreal J. C. Caicedo W. Aperador P. Prieto 《Journal of Materials Engineering and Performance》2014,23(11):3963-3974
Mechanical and tribological evolution on 4140 steel surfaces coated with hafnium nitride/vanadium nitride [HfN/VN] n multilayer systems deposited in various bilayer periods (Λ) via magnetron sputtering has been exhaustively studied in this work. The coatings were characterized in terms of structural, chemical, morphological, mechanical, and tribological properties by x-ray diffraction (XRD), x-ray photo electron spectroscopy (XPS), atomic force microscopy, scanning and transmission electron microscopy, nanoindentation, pin-on-disk, and scratch tests. Moreover, the failure mode mechanisms were observed via scanning electron microscopy. The XRD results showed preferential growth in the face-centered cubic (111) crystal structure for [HfN/VN] n multilayered coatings. The best enhancement of the mechanical behavior was obtained when the bilayer period (Λ) 15 nm (n = 80), yielding the highest hardness (37 GPa), and elastic modulus (351 GPa). The values for the hardness and elastic modulus were 1.48 and 1.32 times greater than the coating with n = 1, respectively, as well the lowest friction coefficient (~0.15) and the highest critical load (72 N). These results indicated significant enhancements in mechanical, tribological, and adhesion properties, compared to HfN/VN multilayered systems with bilayer period (Λ) of 1200 nm (n = 1). This hardness and toughness enhancement in the multilayered coatings could be attributed to the different mechanisms that produce the layer formation with nanometric thickness due to the number of interfaces acting as obstacles for crack deflection and dissipation of crack energy. Due to the emergent characteristics of the synthesized multilayered, the developed adaptive coating could be considered as higher ordered tool machining systems, capable of sustaining extreme operating conditions for industrial applications. 相似文献
56.
1IntroductionAcommonrequirementofcompaniesfromtheirmaintenanceprogramsistohavethemaximumavailabilityoftheirproductionprocesses.ManufacturersnowhavediagnosticequipmentthatenablesthemtOmonitortheirpreductionprocessesatalltimes.Maintenanceplanning,there... 相似文献
57.
Miguel Angel Cárdenas Rosestela Perera Norky Villarreal Carmen Rosales José María Pastor 《应用聚合物科学杂志》2007,106(4):2298-2312
Binary blends of metallocene polyethylenes with polyethylenes and polypropylene were made in a co‐rotating twin‐screw extruder. A stretching process was carried out afterwards in the melt state at the extruder's exit to study the effect of the induced orientation on their thermal and tensile properties. Capillary rheometry was performed to the neat polymers to determine the viscosity ratios of the blend components as a function of the shear rate. SEM and Micro‐Raman analyses were done to study the morphology of the stretched and nonstretched blends. As expected, an increase in the modulus and tensile stress was obtained through blending. Additionally, the elastomeric behavior of the metallocene polyethylene (mPE) sample is observed in all blends and it was not lost through blending. Nevertheless, all blends without stretching exhibited a negative deviation of the linear additivity rule of blending. The stretching of the blends made with metallocene polyethylenes as matrices and other types of PEs as dispersed phase did not improve the tensile properties, although some differences in the dispersed phases were found by DSC, and microfibrils could be seen in the drawn mPE/HDPE blend. However, blending with PP produced an improvement in the modulus and tensile stress of the drawn samples in comparison to their undrawn counterpart. The tensile stresses of PP blends are more sensitive to the drawing process than the modulus, which can be attributed to the appearance of large fibril fractions during this process. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
58.
Natalia M Villarreal Claudia A Bustamante Pedro M Civello Gustavo A Martínez 《Journal of the science of food and agriculture》2010,90(4):683-689
BACKGROUND: Strawberry is a soft fruit, considered as non‐climacteric, being auxins the main hormones that regulate the ripening process. The role of ethylene in strawberry ripening is currently unclear and several studies have considered a revision of the possible role of this hormone. RESULTS: Strawberry fruit were harvested at the white stage and treated with ethephon, an ethylene‐releasing reagent, or 1‐methylcyclopropene (1‐MCP), a competitive inhibitor of ethylene action. The effects of the treatments on fruit quality parameters and on the activity of enzymes related to anthocyanin synthesis and cell wall degradation were evaluated. Some aspects of ripening were accelerated (anthocyanin accumulation, total sugar content and increment of phenylalanine ammonia‐lyase (PAL; EC 4.3.1.24) and β‐galactosidase (EC 3.2.1.23) activities), while others were repressed (chlorophyll levels and increment of endo‐1,4‐β‐glucanase (EC 3.2.1.4) and β‐xylosidase (EC 3.2.1.37) activities) or unchanged (reducing sugar content, pH, titratable acidity and α‐L ‐arabinofuranosidase (EC 3.2.1.55) activity) by ethylene. 1‐MCP treatment caused the opposite effect. However, its effects were more pronounced, particularly in anthocyanin accumulation, phenolics, PAL and polygalacturonase (EC 3.2.1.15 and EC 3.2.1.67) activities. CONCLUSION: These observations probably indicate that strawberry produces low levels of ethylene that are sufficient to regulate some ripening aspects. Copyright © 2010 Society of Chemical Industry 相似文献
59.
Abdel-Basset Mohamed Hessin Abdel-Naser Abdel-Fatah Lila 《Neural computing & applications》2018,29(2):345-361
Nature-inspired metaheuristic algorithms are considered as the most effective techniques for solving various optimization problems. This paper provides a briefly review of the key features of the cuckoo-inspired metaheuristics: cuckoo search (CS) and cuckoo optimization algorithm (COA). In addition, it discusses some of their important and emerging studies, investigates their applications in several fields, and finally clarifies the differences between both algorithms so as to remove confusion between them.
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