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41.
Fawzi Daoud 《Personal and Ubiquitous Computing》1998,2(3):200-211
Electronic commerce is just beginning to be realisable. A number of technological, sociological and economic developments will be required before a large-scale roll out of electronic commerce can be expected. An architectural framework should be defined and needs to incorporate the semantics of contracting and negotiation based on knowledge technology. Electronic commerce has recently increased the demand for personalisation capabilities dramatically. This would imply the use of user-adaptive agents. Because electronic commerce is intrinsically interactive with virtual catalogues, this framework should make such interaction possible. This framework is centred around the Cyber e-Broker concept based on knowledge-based agents. Electronic commerce involves parties that may belong to different domains or administrations with different ontologies. This framework should enable manipulation of such information and enable conversion between ontologies. The e-broker ensures the correct negotiation protocols, and enforces the constraints and contracts, but also interacts with the virtual catalogues. 相似文献
42.
Antifungal activity of five different essential oils in vapour phase for the control of Colletotrichum gloeosporioides and Lasiodiplodia theobromae in vitro and on mango
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Anand Babu Perumal Periyar Selvam Sellamuthu Reshma B. Nambiar Emmanuel Rotimi Sadiku 《International Journal of Food Science & Technology》2016,51(2):411-418
Mango fruit has high commercial value; however, major postharvest losses are encountered throughout the supply chain due to postharvest diseases. These results lead to the search for natural fungicide for postharvest diseases control. The antifungal effects of five essential oils (thyme, clove, cinnamon, anise and vitex) were assessed by disc volatilisation method. Thyme oil vapours at 5 μL per Petriplate, and clove and cinnamon oil at 8 μL per Petriplate showed 100% growth inhibition of mango pathogens in vitro. GC/MS analysis of essential oil showed thymol (23.88), o‐cymol (23.88) and terpinolene (23.88) as the major constituents of thyme oil. Clove and cinnamon oils contain 3‐allyl‐2‐methoxyphenol (37.42%) and benzofuran 3‐methyl (17.97%), respectively. Thyme oil as a fumigant at 66.7 μL L?1 showed a significant (P < 0.05) inhibition on postharvest pathogens of mango fruits stored at 25 °C for 6 days. Results of our study suggest the possibility of using thyme oil as an alternate natural fungicide to manage postharvest diseases in mango. 相似文献
43.
《International Journal of Hydrogen Energy》2021,46(57):29529-29540
This study presents research results on electricity production from waste activated sludge using MFCs during stabilization process. Different MFC configurations equipped with various electrodes were used. Voltage measurements were continuously done during 35 days of MFC operation. Experimental results showed that bioelectricity generation was linked to volatile solids (VS) and protein reductions as a fraction of extracellular polymeric substances (EPS). Double chamber MFC reactor equipped with graphite electrodes had better power and current densities as 312.98 mW/m2 and 39.07 μA/cm2 while single chamber MFC equipped with titanium electrodes revealed better power and current densities as 97.60 mW/m2 and 17.63 μA/cm2, respectively. Molecular results indicated that power outputs of MFCs effected by diverse microbial communities in anode biofilms. Although organic matter degradation is reported as 35%–55% VS reduction for digesters, this research provided a promising approach for sludge stabilization with enhanced degrading of organic matters up to 75% by using MFCs. 相似文献
44.
Facing increasing open innovation trends, Portuguese enterprises are considering the related processes and impacts. Thus, this work aims to identify the sectors whose enterprises most engage in open innovation (such as cooperation on this issue) and which sources/agents are most used. This is analyzed by sector and type of innovation as an interesting way of differentiation for better open innovation strategy delineation. Using the data from the Community Innovation Survey (CIS-2012), it first appraises the nature of the innovation process, either cooperative or firm-based, as the starting level of analysis. Then, it differentiates the results by sector illustrating which cooperation sources/agents are most used (scope) and relative intensity of use (scale). This is important to assess levels of openness and related factors. Results show that main innovating sectors in Portugal are of three types: research-based, knowledge-based and service-based. They reveal an increasing focus on knowledge and services, trends that have been leading to more active openness towards innovation. For instance, health and construction are increasing their openness for innovating and internationalizing processes. However, Portuguese innovation is still more firm-based (in-house) than cooperation-based, especially concerning new products' launching. This work and future analyzes around it can contribute to encourage the open innovation strategy in more sectors of the economy as an easy and effective way to cope with rapid trends and changes. 相似文献
45.
《Expert systems with applications》2014,41(15):6688-6700
This paper presents a control system, based on artificial intelligence technologies, that implements multiple intelligences. This system aims to support and improve automatic telecontrol of solar power plants, by either automatically triggering actuators or dynamically giving recommendations to human operators. For this purpose, the development of a MultiAgent System is combined with a variety of inference systems, such as Expert Systems, Neural Networks, and Bayesian Networks. This diversity of intelligent technologies is shown to result in an efficient way to mimic the reasoning process in human operators. 相似文献
46.
在传统石灰中和处理法的基础上,提出了酸法难浸废水用“石灰石-石灰两步中和-沉渣循环”的流程进行处理。废水先与廉价的石灰石接触反应,使废水中的强酸中和并使铁、铝等金属离子在较低pH值下形成氢氧化物,再用石灰乳进一步中和到要求的pH。生成的沉淀物(沉渣)在过程中不断循环。该方法与一次石灰中和法相比,试剂费用节省1/3,沉渣生成量(以体积计)减少2/3,并且沉渣的过滤和沉降性能也有所改善。本工作还对沉渣减容与改性的机理进行了研究探讨。 相似文献
47.
The stickiness of sludge during the drying process is an effect of its adhesion and cohesion. Furthermore, the adhesion and cohesion characteristics of sludge are comprehensive results of sludge components and their correlation with moisture. This work presents a simple method to test the adhesion and cohesion characteristics of sludge during the drying process based on the Jenike shear test. The results show that the most significant sludge adhesion and cohesion emerges at a moisture content of approximately 45 to 70% and 30 to 60%, respectively, and at a heating temperature of 120°C. An increase of the heating temperature to 200°C only brings a small movement to the sticky range location. The possible reasons for sludge adhesion and cohesion are discussed based on the results of sludge component analysis. The contributions of mineral materials with tiny particle sizes and metal salts to the adhesion and cohesion are discussed in this study because the contribution of organic matter has been widely demonstrated. The adhesion and cohesion nature of sludge exhibits a large effect on its drying characteristics. A remarkable fluctuation of both the drying rate and stirring power, located between the first and second falling rate period, is observed when the adhesion force of sludge reaches the maximum. When the sludge cohesion force decreases to approximately 3800 N/m2, sludge bulks are broken with the stirring of paddles. 相似文献
48.
49.
T. M. T. Gasi L. A. V. Amaral C. E. M. Pacheco A. G. Filho A. D. Garcia Jr. S. M. M. Vieira 《臭氧:科学与工程》1991,13(2):179-193
Ozonation can improve the effluent characteristics of UASB (upflow anaerobic sludge blanket) reactors treating domestic sewage, by removing organic matter, solids, surfactants, color and microorganisms. In Brazil, part of the effluent of a 120 msup3; UASB reactor, fed with screened domestic sewage at an hydraulic retention time of 7 hours, was post-treated in a two-column ozonation system of 300 liters total volume. With a contact time of 50 minutes and ozone application dosage of 16.7 mg/L, the following removals were obtained at the ozonation step: 51‰ BOD, 56‰COD, 76‰ TSS, 62‰ color, and 91‰ surfactants. Pathogens and indicator organisms were inactivated to over 99.9‰. Ozonation completely destroyed Salmonella, protozoa cysts and helminth eggs and larvae. 相似文献
50.
The cationic organic polymers used to enhance thickening and dewatering processes are potential sources of strong odors. These polymers vary in chemical structure, and some may be more susceptible to biotic or abiotic degradation than others. The product organic amines will be volatilized most noticeably at high pH, as in lime addition. These possibilities were examined using several structural types of polymers combined with anaerobically digested sludge. Two commonly used polymers gave significant production of trimethylamine (TMA), which was released upon lime addition. Their structures were correlated with reactions that yield TMA. An initial ester hydrolysis step appears to be biologically mediated, but subsequent steps can occur due to alkaline conditions. An alternative cationic polymer structure did not generate TMA but required a much higher dose to effect sufficient conditioning of the sludge. The acrylamide-based polymers were shown to be the predominant source of TMA in limed sludges. 相似文献