Open-loop and feedback-controlled mouse cursor movements in linear paths

Path length (A), path width (W) and movement direction (θ) are identified as the main factors affecting visually-controlled movement times in linear paths. Effects of A and W are well described by Drury's ( 1971 . Movements with lateral constraint. Ergonomics, l4 (2), 293-305.) model in which movement time is linearly related to the ratio of A/W. At low A/W values, departure from linearity has been identified but not investigated in detail. Data are presented for both open-loop and feedback-controlled movements in linear paths at 0, 60 and 150° movement directions. Movement amplitude and path width were varied over a wide range to determine the effects of A and (A/W) on movement time. Movements were found to be made ballistically or in open-loop mode when the ratio (A/W) was less than about 8 to 10 and the movement times were linearly related to √A for all angles of movement. Feedback-controlled movements followed Drury's law; ballistic movements had movement speed linear with √A. PRACTITIONER SUMMARY: Many tasks require manoeuvring equipment or devices through a path of limited width. These movements can be made with or without feedback control, depending on the path constraints. The conditions for the two forms of movement are determined in this research.     

Data reduction algorithm based on principle of distributional equivalence for fault diagnosis

Historical data based fault diagnosis methods exploit two key strengths of multivariate statistical approaches, viz.: (i) data compression ability, and (ii) discriminatory ability. It has been shown that correspondence analysis (CA) is superior to principal components analysis (PCA) on both these counts (Detroja, Gudi, Patwardhan, & Roy, 2006a), and hence is more suited for the task of fault detection and isolation (FDI). In this paper, we propose a CA based methodology for fault diagnosis that can facilitate significant data reduction as well as better discrimination. The proposed methodology is based on the principle of distributional equivalence (PDE). The PDE is a property unique to the CA algorithm and can be very useful in analyzing large datasets. The principle, when applied to historical data sets for FDI, can significantly reduce the data matrix size without significantly affecting the discriminatory ability of the CA algorithm. This can significantly reduce computational load during statistical model building. The data reduction ability of the proposed methodology is demonstrated using a simulation case study involving benchmark quadruple tank laboratory process. The proposed methodology when applied to experimental data obtained from the quadruple tank process also demonstrated data reduction capabilities of the principle of distributional equivalence. The above aspect has also been validated for large-scale data sets using the benchmark Tennessee Eastman process simulation case study.     

Stem Cell Models for Cancer Therapy

Metastatic progression of female breast and colon cancer represents a major cause of mortality in women. Spontaneous/acquired resistance to conventional and targeted chemo-endocrine therapy is associated with the emergence of drug-resistant tumor-initiating cancer stem cell populations. The cancer-initiating premalignant stem cells exhibit activation of select cancer cell signaling pathways and undergo epithelial–mesenchymal transition, leading to the evolution of a metastatic phenotype. The development of reliable cancer stem cell models provides valuable experimental approaches to identify novel testable therapeutic alternatives for therapy-resistant cancer. Drug-resistant stem cell models for molecular subtypes of clinical breast cancer and for genetically predisposed colon cancer are developed by selecting epithelial cells that survive in the presence of cytostatic concentrations of relevant therapeutic agents. These putative stem cells are characterized by the expression status of select cellular and molecular stem cell markers. The stem cell models are utilized as experimental approaches to examine the stem-cell-targeted growth inhibitory efficacy of naturally occurring dietary phytochemicals. The present review provides a systematic discussion on (i) conceptual and experimental aspects relevant to the chemo-endocrine therapy of breast and colon cancer, (ii) molecular/cellular aspects of cancer stem cells and (iii) potential stem-cell-targeting lead compounds as testable alternatives against the progression of therapy-resistant breast and colon cancer.     

TIO2/Nanoclay nanocomposite for phenol degradation in sonophotocatalytic reactor

A TiO₂–nanoclay nanocomposite was used as a photocatalyst for the degradation of phenol in presence of acoustic cavitation. TiO₂–nanoclay nanocomposite was synthesised in benzyl alcohol medium wherein TiO₂ nanoparticles were formed between the nanoclay platelets. The synthesised product was characterised by using FTIR, XRD and TEM techniques. TEM image shows that TiO₂–nanoclay nanocomposite particles were in the range of 30–40 nm. XRD gram confirms the formation of nanocomposite of TiO₂ nanoclay. The effect of cavitation and TiO₂–nanoclay nanocomposite photocatalyst on phenol removal was investigated. The effects of various parameters such as nanocomposite loading, initial concentration, etc., have been studied. On comparing the results obtained with that of nanocomposite without UV, it was found for an initial concentration of 500 mg/L of phenol, the TiO₂–nanoclay nanocomposite exhibited higher percentage of pollutant removal (59%) and for nanoclay it was 47%. © 2011 Canadian Society for Chemical Engineering     

A double-filter-structure based COMPASS/INS deep integrated navigation system implementation and tracking performance evaluation

Beidou or COMPASS is a Chinese GNSS(global navigation satellite system).Like the GPS receiver,the COMPASS receiver also faces the challenge of choosing an optimal bandwidth to satisfy both anti-jamming capability and dynamics adaptation simultaneously.GPS/INS(inertial navigation system)deep integrated navigation system has solved this problem by fusing GPS baseband signal and INS information in a deeply coupled mode.In this study,a COMPASS B3 frequency is considered and a traditional federated GPS/INS deep integration model is used to derive a single-filter-structure based COMPASS/INS deep integration model.Besides,a double-filter-structure based COMPASS/INS deep integration model is proposed.The simulation results show a better carrier tracking performance,especially a better dynamics adaptation.The impact of IMU errors and vehicle’s dynamics on carrier tracking performance of the double-filter-structure based COMPASS/INS deep integrated navigation system are evaluated in simulated and field environments.Simulation and field test results are in accordance with the theory analysis.     

Detecting localized homogeneous anomalies over spatio-temporal data

The last decade has witnessed an unprecedented growth in availability of data having spatio-temporal characteristics. Given the scale and richness of such data, finding spatio-temporal patterns that demonstrate significantly different behavior from their neighbors could be of interest for various application scenarios such as—weather modeling, analyzing spread of disease outbreaks, monitoring traffic congestions, and so on. In this paper, we propose an automated approach of exploring and discovering such anomalous patterns irrespective of the underlying domain from which the data is recovered. Our approach differs significantly from traditional methods of spatial outlier detection, and employs two phases—(i) discovering homogeneous regions, and (ii) evaluating these regions as anomalies based on their statistical difference from a generalized neighborhood. We evaluate the quality of our approach and distinguish it from existing techniques via an extensive experimental evaluation.     

Adaptive encoding of zoomable video streams based on user access pattern

Zoomable video allows users to selectively zoom and pan into regions of interest within the video for viewing at higher resolutions. Such interaction requires dynamic cropping of RoIs on the source video. We have previously explored two different ways of encoding and transmitting video to support dynamic RoI cropping: (i) Monolithic streaming uses a standard video encoder to encode the video. When an RoI is requested, the bits belonging to the RoI along with other bits required to decode the RoIs (due to encoding dependencies) are transmitted. (ii) Tile streaming divides regions in the standard video into rectangular tiles that are encoded independently. The tiles that intersect with a requested RoI are transmitted. In this paper, we consider how the bandwidth needed to transmit the RoIs can be reduced by carefully encoding the source video for each of the two encoding schemes. The goal is to support bandwidth efficient compressed domain RoI cropping in the context of virtual zoom and pan by tuning encoder parameters. Our key idea is to exploit user access patterns to the RoIs, and encode different regions of the video with different encoding parameters based on the popularity of the region. We show that our encoding method can reduce the expected bandwidth by up to 43% in the test video sequence which we have used.     

Multistage bayesian autonomy for high‐precision operation in a large field

This paper presents a generalized multistage bayesian framework to enable an autonomous robot to complete high‐precision operations on a static target in a large field. The proposed framework consists of two multistage approaches, capable of dealing with the complexity of high‐precision operation in a large field to detect and localize the target. In the multistage localization, locations of the robot and the target are estimated sequentially when the target is far away from the robot, whereas these locations are estimated simultaneously when the target is close. A level of confidence (LOC) for each detection criterion of a sensor and the associated probability of detection (POD) of the sensor are defined to make the target detectable with different LOCs at varying distances. Differential entropies of the robot and target are used as a precision metric for evaluating the performance of the proposed approach. The proposed multistage observation and localization approaches were applied to scenarios using an unmanned ground vehicle (UGV) and an unmanned aerial vehicle (UAV). Results with the UGV in simulated environments and then real environments show the effectiveness of the proposed approaches to real‐world problems. A successful demonstration using the UAV is also presented.     

An improved tri-reforming based methanol production process for enhanced CO2 valorization

The consistent rise of CO₂ concentration in the atmosphere is known to be significantly detrimental to the environment. Thus, mitigating CO₂ has become an urgent necessity. Current methods involving CO₂ mitigation can be broadly divided into two major categories which involve (i) CO₂ capture and sequestration (CCS) and (ii) CO₂ capture and valorization. Since, production of fuels/chemicals is an added feature along with mitigation in CO₂ valorization based methods, they could be economically favorable. An energy intensive CO₂ capture step is a common drawback of most CO₂ valorization methods that aim to mitigate CO₂ from major CO₂ emission sources (such as industrial flue gases). In this paper we employ and analyze a relatively new process called tri-reforming [1,2] which was developed to directly convert power plant based flue gases to synthesis gas, while avoiding the capture step. This paper is presented as an improvement over a tri-reforming coupled methanol production process as developed by Zhang et al. [3]. The process in Zhang et al. [3] involves utilizing tri-reforming process using flue gas and methane to produce synthesis gas which is then converted to methanol in the next step. The main contributions of this paper to the tri-reforming coupled methanol production process are: (i) proposition of a high pressure tri-reforming step to limit capital costs of the process (ii) establishment of steam input coupled with water separation step as a process improvement whose impact is shown to further amplify at higher tri-reformer pressures. The paper evaluates the process in terms of the profit generating and CO₂ valorization potential of the process as reflected by two parameters, gross margin (GM) and NPCV (net percentage of CO₂ valorized) respectively. In the proposed approach, higher pressures were utilized in the tri-reforming process to ensure economic feasibility of the process by limiting the reactor volume. The process improvements for the flowsheet containing the steam input combined with water separation (SWS) step over the one without these steps (termed as WSWS) are demonstrated in terms of an increase in GM/NPCV values at various pressures. The results indicate substantial improvements in GM and NPCV values (especially at higher tri-reformer pressures) ranging from 24.30 to 84.96% and 28.80–78.44% respectively in SWS cases over WSWS cases at various pressures. The simulations have been carried out in Aspen Plus V8.4 and are optimized using sensitivity analysis.     

Study of physicochemical properties of flutamide-loaded Ocimum basilicum microspheres with ex vivo mucoadhesion and in vitro drug release

Drug which shows extensive first pass effect is difficult task that, needs to be solved by formulators in the pharmaceutical science. The low oral bioavailability (49%) of flutamide may be due to poor wettability, low aqueous solubility and extensive first pass effect. The aim of present investigation was to prepare flutamide loaded microspheres and incorporate it into suppositories for rectal delivery to avoid first pass effect and enhance residence time. Flutamide loaded mucoadhesive microspheres of Ocimum Basilicum mucilage (OBM) were prepared using spray drying and characterized by percent production yield, encapsulation efficiency, particle size, zeta potential, polydispersity index, DSC, SEM, XRPD, in vitro drug release and stability studies. Moreover, ex vivo mucoadhesion was investigated using falling liquid film technique to determine the adhesion of microspheres to sheep rectal mucosa. The microspheres had nearly spherical shape and size about 2.53?μm. The encapsulation efficiency and mucoadhesion of optimized formulation MBF10 were found to be 69.6?±?2.3% and 89.01?±?2.18%, respectively. Percent CDR of optimized flutamide loaded mucoadhesive microspheres was found to be 88.7?±?1.3 at 7?h. In conclusion, OBM microparticles based suppository could be used to deliver drug through rectal delivery.