Hierarchical congregated ant system for bottom-up VLSI placements

A new perturbation method, called Hierarchical-Congregated Ant System (H-CAS) has been proposed to perform the variable-order bottom-up placement for VLSI. H-CAS exploits the concept of ant colonies, where each ant will generate the perturbation based on differences in dimensions of the VLSI modules in hard modules floorplanning and differences in area of the VLSI modules in soft modules floorplanning. In this paper, it is mathematically proved that the area-based two-dimensional cost function for hard modules floorplanning problem can be reduced to the difference-based one dimensional cost function which avoids local optima problems. Lack of global view is a major drawback in the conventional bottom-up hierarchy, and hence, ants in the H-CAS are made to introduce global information at every level of bottom-up hierarchy. A new relative whitespace formula for bottom-up hierarchy is derived mathematically and the H-CAS embeds it in its unique update formula. The ants in H-CAS are able to communicate among themselves and update the pheromone trails when they reach the destination. Then, the ants will congregate, share their experiences and construct a new pheromone trails that belong to this newly constructed group. The congregation of at least two ants and/or ant consortiums would lead to reduction in subsequent search space and complexity. H-CAS gives the best-so-far near optimal solutions and yields low standard deviations of areas involving 9–600 blocks based on Microelectronics Center of North Carolina (MCNC) and Giga scale Systems Research Center (GSRC) benchmarks. The results obtained establish that H-CAS is a high performance placer in respect of scaling, convergence, precision, stability, and reliability. The above claims are based on the comparisons with the other floorplanning algorithms as depicted graphically.     

Critical review on conventional spectroscopic α-amylase activity detection methods: merits,demerits, and future prospects

α-Amylase is an endoenzyme that catalyses the hydrolysis of internal α-l,4 glycosidic linkages in polysaccharides to produce maltose, maltotriose, and α-limit dextrins. It is widely used in the laboratorial and industrial workflow for several applications. There are several methods utilizing different techniques and substrates to assess α-amylase activity, among which the spectroscopic methods have found widespread applicability due to their ease of use and cost-effectiveness. Depending upon the reaction principle, these assays are classified into four groups: reducing sugar, enzymatic, chromogenic, and amyloclastic methods. Despite the presence of numerous methods, there is no general reliable method to assess α-amylase activity. Each method is shown to have its own merits and demerits. Many improvements have been made to make the available methods more accurate, reliable, and easy. This communication briefly discusses the basic reaction mechanisms and critically reviews the advantages and shortcomings associated with each method. Further recommendations are made for future development. © 2020 Society of Chemical Industry     

Voltammetric Method for Manganese Analysis in Indian Traditional Leafy Vegetables and Medicinal Plants Collected Around Tirupati Town, a Famous Pilgrim Center in India: The Catalytic Hydrogen Wave (CHW) Technique

Cost-effective, rapid, sensitive, and novel catalytic hydrogen wave technique (CHW) was developed for the analysis of manganese(II) in NH₄Cl–NH₄OH medium at pH 6.2 and produced catalytic hydrogen waves at −0.60 and −0.56 V Vs SCE with ammonium piperidine dithiocarbamate and ammonium morpholine dithiocarbamate, respectively, in various leafy vegetables and medicinal plants collected around Tirupati, Chittoor District, Andhra Pradesh which is one the famous pilgrim centers in India. Different optimal parameters like effect of pH, supporting electrolyte (NH₄Cl–NH₄OH) concentration, ligand and metal ion concentrations, and effect of adverse ions on peak height were studied to improve the sensitivity, selectivity, and detection limits CHW technique. This technique was compared in terms of Student t test and variance ratio f test with differential pulse polarography (DPP) method. The technique was applied for the analysis of manganese(II) in leafy vegetables and medicinal plants. The results obtained are in good agreement with DPP.     

Study of n-ZnO/p-Si (100) thin film heterojunctions by pulsed laser deposition without buffer layer

ZnO/Si heterojunctions were fabricated by growing ZnO thin films on p-type Si (100) substrate by pulsed laser deposition without buffer layers. The crystallinity of the heterojunction was analyzed by high resolution X-ray diffraction and atomic force microscopy. The optical quality of the film was analyzed by room temperature (RT) photoluminescence measurements. The high intense band to band emission confirmed the high quality of the ZnO thin films on Si. The electrical properties of the junction were studied by temperature dependent current-voltage measurements and RT capacitance-voltage (C-V) analysis. The charge carrier concentration and the barrier height (BH) were calculated, to be 5.6 × 10¹⁹ cm^− 3 and 0.6 eV respectively from the C-V plot. The BH and ideality factor, calculated using the thermionic emission (TE) model, were found to be highly temperature dependent. We observed a much lower value in Richardson constant, 5.19 × 10^− 7 A/cm² K² than the theoretical value (32 A/cm² K²) for ZnO. This analysis revealed the existence of a Gaussian distribution (GD) with a standard deviation of σ² = 0.035 V. By implementing the GD to the TE, the values of BH and Richardson constant were obtained as 1.3 eV and 39.97 A/cm² K² respectively from the modified Richardson plot. The obtained Richardson constant value is close to the theoretical value for n-ZnO. These high quality heterojunctions can be used for solar cell applications.     

Effect of orally administered betel leaf (Piper betle Linn.) on digestive enzymes of pancreas and intestinal mucosa and on bile production in rats

The influence of two varieties of betel leaf (Piper betle Linn.) namely, the pungent Mysore and non-pungent Ambadi, was examined on digestive enzymes of pancreas and intestinal mucosa and on bile secretion in experimental rats. The betel leaves were administered orally at two doses which were either comparable to human consumption level or 5 times this. The results indicated that while these betel leaves do not influence bile secretion and composition, they have a significant stimulatory influence on pancreatic lipase activity. Besides, the Ambadi variety of betel leaf has a positive stimulatory influence on intestinal digestive enzymes, especially lipase, amylase and disaccharidases. A slight lowering in the activity of these intestinal enzymes was seen when Mysore variety of betel leaf was administered, and this variety also had a negative effect on pancreatic amylase. Further, both the betel leaf varieties have shown decreasing influence on pancreatic trypsin and chymotrypsin activities.     

Synthesis and characterization of TS-48, a titanium containing silica analog of ZSM-48

Crystalline titanium containing silica analog of ZSM-48 (TS-48) samples were synthesized using soluble peroxytitanate, fumed silica and diamino octane. All samples were characterized using a variety of techniques including XRD, IR, AAS, SEM, UV-Vis, XANES and catalytic testing in hydroxylation of phenol. Data suggest that titanium in these materials is linked to the framework. However, it was impossible to incorporate more than about 2 wt% Ti in the zeolite lattice. TS-48 samples prepared by this method had no activity for hydroxylation of phenol in the presence of hydrogen peroxide. The lack of activity of this material even though it showed all of the regular characteristics of other catalytically active titanium silicalites (i.e., TS-1 and TS-2) could be due either to diffusional limitations or to subtle differences in titanium environment.     

Preparation and properties of in‐situ polymerized polyurethane/stearate intercalated layer double hydroxide nanocomposites

The present work deals with the effect of stearate intercalated layered double hydroxide (St‐LDH) loadings on the morphological, mechanical, thermal, adhesive and flame retardant properties of polyurethane (PU)/St‐LDH nanocomposites prepared by the in situ polymerization method. X‐ray diffraction and transmission electron microscopy studies confirmed that exfoliation takes place at 3 wt% loading followed by intercalation at higher filler loadings in the PU matrix. The exfoliated structure has been further verified by atomic force microscopy. The measurements of stress‐strain, thermogravimetric analysis, dynamic mechanical analysis, lap shear strength and peel strength analysis showed that the nanocomposites containing 3 wt% St‐LDH exhibit excellent improvement in tensile strength (ca 175%) and log storage modulus (ca 14%), while PU/St‐LDH (5 wt%) possesses optimum improvement in glass transition temperature (ca 6 °C), lap shear strength (200%) and peel strength (130%) over neat PU. In addition, the gradual improvements in limiting oxygen index value with St‐LDH loading indicated the higher effectiveness in providing better barrier properties as well as better flame retardant behavior. Copyright © 2012 Society of Chemical Industry     

Simultaneous optimization of multiple performance characteristics in coagulation-flocculation process for Indian paper industry wastewater

The goal of this study was to optimize the coagulation-flocculation process in wastewater generated from the paper and pulp industry using a grey relational analysis (GRA)-based Taguchi method. Process parameters included types and doses of natural coagulants and coagulant aid, and pH. To track the efficiency of the treatment process, the following responses were chosen for optimization: chemical oxygen demand (COD), total dissolved solids (TDS) and turbidity of wastewater, alone or in combination or all together. Analysis of variance showed that the type and dose of the coagulant aid were the most significant parameters, followed by pH and the dose of the coagulant; the type of coagulant used was found to be insignificant in the coagulation-flocculation process. Optimization of process parameters to achieve lower turbidity and greater removal of COD and TDS was verified in a separate confirmatory experiment, which showed improvements in COD and TDS removal and a decrease in turbidity of 8.2, 6.35 and 26.17%, respectively, with the application of the Taguchi method and GRA.     

User Experience of On-Screen Interaction Techniques: An Experimental Investigation of Clicking,Sliding, Zooming,Hovering, Dragging,and Flipping

From scrolling and clicking to dragging, flipping, sliding, hovering, and zooming, the wide array of interaction techniques has vastly expanded the range of user actions on an interface. Each of these interaction techniques affords a distinct action. But do these techniques differ in their ability to engage users and contribute to their user experience? Furthermore, do they affect how users view the content and how much they learn from it? We address these questions via two between-subjects laboratory experiments. Study 1 (N = 128) investigated the relative effects of six on-screen interaction techniques (click-to-download, drag, mouseover, slide, zoom, and 3D carousel) on users' assessment of—as well as their engagement with—an informational website. The site for each condition was identical in content and design, except for the interaction technique used, so that we could isolate the effects of each technique on various cognitive, attitudinal and behavioral outcomes. Study 2 (N = 127) examined the relative effects of four combinations of interaction techniques (slide+click, slide+mouseover, drag+mouseover, and drag+zoom) on the same dependent variables. Data from Study 1 suggest that although the 3D carousel generates more user action, the slide is better at aiding memory. The zoom-in/out tool was the least favored, whereas the mouseover feature fostered greater engagement among power users. Findings from Study 2, which was conducted with a different content domain, replicated the positive effects of slide and negative effects of drag in influencing user experience. Path analyses, using structural equation modeling, revealed the importance of users' assessment of the interface (perceived levels of natural mapping, intuitiveness, and ease of use), which can have significant consequences for user engagement as well as resulting attitudes and behavioral outcomes. Design insights, theories, and techniques to test and capture user experience are discussed.     

Improved Secure Identification-Based Multilevel Structure of Data Sharing in Cloud Environments

The Cloud Computing Environment (CCE) developed for using the dynamic cloud is the ability of software and services likely to grow with any business. It has transformed the methodology for storing the enterprise data, accessing the data, and Data Sharing (DS). Big data frame a constant way of uploading and sharing the cloud data in a hierarchical architecture with different kinds of separate privileges to access the data. With the requirement of vast volumes of storage area in the CCEs, capturing a secured data access framework is an important issue. This paper proposes an Improved Secure Identification-based Multilevel Structure of Data Sharing (ISIMSDS) to hold the DS of big data in CCEs. The complex file partitioning technique is proposed to verify the access privilege context for sharing data in complex CCEs. An access control Encryption Method (EM) is used to improve the encryption. The Complexity is measured to increase the authentication standard. The active attack is protected using this ISIMSDS methodology. Our proposed ISIMSDS method assists in diminishing the Complexity whenever the user’s population is increasing rapidly. The security analysis proves that the proposed ISIMSDS methodology is more secure against the chosen-PlainText (PT) attack and provides more efficient computation and storage space than the related methods. The performance of the proposed ISIMSDS methodology provides more efficiency in communication costs such as encryption, decryption, and retrieval of the data.