1,073 research outputs found
Stabilizing Stochastic Predictive Control under Bernoulli Dropouts
This article presents tractable and recursively feasible optimization-based
controllers for stochastic linear systems with bounded controls. The stochastic
noise in the plant is assumed to be additive, zero mean and fourth moment
bounded, and the control values transmitted over an erasure channel. Three
different transmission protocols are proposed having different requirements on
the storage and computational facilities available at the actuator. We optimize
a suitable stochastic cost function accounting for the effects of both the
stochastic noise and the packet dropouts over affine saturated disturbance
feedback policies. The proposed controllers ensure mean square boundedness of
the states in closed-loop for all positive values of control bounds and any
non-zero probability of successful transmission over a noisy control channel
Paclitaxel delivery by micro/nano encapsulation using layer-by-layer assembly
A novel formulation of paclitaxel (PTX) has been developed by providing multilayer assembly over drug loaded porous CaCO3 microparticles (CaCO3 MP) using combination of biocompatible and biodegradable polyelectrolytes (PE’s). PTX was encapsulated into the nanopores of preformed CaCO3 MP prepared by the co-precipitation method. Infrared (IR) and X-ray diffraction (XRD) provides evidences that PTX has been encapsulated into nanopores of CaCO3 MP and not crystallized on the surface. PTX loaded CaCO3 MP (CaCO3-PTX) was found to be highly stabilized against thermal decomposition as evinced by thermo gravimetric analysis (TGA) indicating decomposition at 600°C and 250°C for CaCO3-PTX and PTX respectively. The multilayer assembly over CaCO3-PTX was effectuated by alternate deposition of protamine sulfate (PRM) and sodium alginate (SA) using LBL technique followed by subsequent core removal [PTX- (PRM/SA)5]. The pay load efficiency of PTX in this system was found to be 78.98±2.14%. The developed system was further evaluated for surface morphology, size and size distribution, surface charge, core removal and layer-by-layer growth due to sequential adsorption of PE’s. The release data of PTX-(PRM/SA)5 was comparable with marketed formulation of PTX (PTX-M) and CaCO3-PTX when performed in simulated intestinal fluid (SIF pH=7.4). The release profile of PTX-(PRM/SA)5 indicates that PEs based multilayer matrix is capable to provide barrier to PTX release as it has been found to follow first order matrix diffusion kinetics with 64±4.8% release within 24 hrs. The t50% of PTX-M, CaCO3-PTX and PTX-(PRM/SA)5 was found to be 70, 90 and 480 minutes respectively. This alternative delivery system of PTX disguised in the form of LBL assembly could have immense application for the treatment of metastasized mammary glands vis-à-vis existing formulation of PTX which is by and large criticized for having certain toxic excipients to be given parentrally. Moreover, the proposed system provides ample of opportunity to modify the surface for targeted application of PTX.

Output feedback stable stochastic predictive control with hard control constraints
We present a stochastic predictive controller for discrete time linear time
invariant systems under incomplete state information. Our approach is based on
a suitable choice of control policies, stability constraints, and employment of
a Kalman filter to estimate the states of the system from incomplete and
corrupt observations. We demonstrate that this approach yields a
computationally tractable problem that should be solved online periodically,
and that the resulting closed loop system is mean-square bounded for any
positive bound on the control actions. Our results allow one to tackle the
largest class of linear time invariant systems known to be amenable to
stochastic stabilization under bounded control actions via output feedback
stochastic predictive control
QudCom: Towards Quantum Compilation for Qudit Systems
Qudit-based quantum computation offers unique advantages over qubit-based
systems in terms of noise mitigation capabilities as well as algorithmic
complexity improvements. However, the software ecosystem for multi-state
quantum systems is severely limited. In this paper, we highlight a quantum
workflow for describing and compiling qudit systems. We investigate the design
and implementation of a quantum compiler for qudit systems. We also explore
several key theoretical properties of qudit computing as well as efficient
optimization techniques. Finally, we provide demonstrations using physical
quantum computers as well as simulations of the proposed quantum toolchain
Security of Electrical, Optical and Wireless On-Chip Interconnects: A Survey
The advancement of manufacturing technologies has enabled the integration of
more intellectual property (IP) cores on the same system-on-chip (SoC).
Scalable and high throughput on-chip communication architecture has become a
vital component in today's SoCs. Diverse technologies such as electrical,
wireless, optical, and hybrid are available for on-chip communication with
different architectures supporting them. Security of the on-chip communication
is crucial because exploiting any vulnerability would be a goldmine for an
attacker. In this survey, we provide a comprehensive review of threat models,
attacks, and countermeasures over diverse on-chip communication technologies as
well as sophisticated architectures.Comment: 41 pages, 24 figures, 4 table
State Preparation on Quantum Computers via Quantum Steering
One of the major components for realizing quantum computers is the ability to
initialize the computer to a known fiducial state, also known as state
preparation. We demonstrate a state preparation method via measurement-induced
steering on contemporary, digital quantum computers. By delegating ancilla
qubits and systems qubits, the system state is prepared by repeatedly
performing the following steps: (1) executing a designated system-ancilla
entangling circuit, (2) measuring the ancilla qubits, and (3) re-initializing
ancilla qubits to known states through active reset. While the ancilla qubits
are measured and reinitialized to known states, the system qubits are steered
from arbitrary initial states to desired final states. We show results of the
method by preparing arbitrary qubit states and qutrit (three-level) states. We
also demonstrate that the state convergence can be accelerated by utilizing the
readouts of the ancilla qubits to guide the protocol in an active manner. This
protocol serves as a nontrivial example that incorporates and characterizes
essential operations such as qubit reuse (qubit reset), entangling circuits,
and measurement. These operations are not only vital for near-term noisy
intermediate-scale quantum (NISQ) applications but are also crucial for
realizing future error-correcting codes
DESIGN, SYNTHESIS AND ANTIFUNGAL EVALUATION OF NOVEL SUBSTITUTED 1, 3, 4-OXADIAZOLES, AND 1, 3, 4-THIADIAZOLES
Objective: The purpose of this research is to evaluate the antifungal activity of synthesized conjugates of thiophene with 1, 3, 4-oxadiazoles and 1, 3, 4-thiadiazoles using in vitro methods.Methods: The series of (IVa-e) and (Va-e) compounds were synthesized from thiosemicarbazide (IIIa-e) series by treating with iodine-sodium hydroxide mixture and by phosphoric acid cyclization respectively. Thiosemicarbazides (IIIa-e) were prepared by the reaction of 2–amino-4, 5, 6, 7-tetrahydro-benzo[b]thiophene-3-carbohydrazide (II) with substituted isothiocyanates. Carbohydrazide (II) was synthesized by the reaction of hydrazine hydrate with ethyl 2–amino-4, 5, 6, 7-tetrahydrobenzeno[b]thiophene-3-carboxylate (I), which was prepared by one pot synthesis method. Finally, the synthesized compound series was characterized by physicochemical and spectral data (IR, NMR and Mass) and evaluated for in vitro antifungal activity against Candida albicans and Aspergillus niger using disc diffusion method. The percentage inhibition was calculated with reference to the standard drug.Results: The structures of the synthesized conjugates of thiophene with 1, 3, 4-oxadiazoles and 1, 3, 4–thiadiazoles were confirmed by IR, NMR, and Mass spectroscopic techniques. The results of bioassay were indicated that some synthesized compounds IVd, IVe, Vd, and Ve exhibited moderate antifungal activities against Candida albicans and Aspergillus niger; whereas compounds IVb, IVc, Vb, and Vc showed prominent antifungal activities when compared to standard drug, Fluconazole. Conclusion: Present study demonstrates the synthesis of conjugates of thiophene with 1, 3, 4-oxadiazoles and 1, 3, 4–thiadiazoles. These compounds were evaluated for in vitro antifungal activity against Candida albicans and Aspergillus niger using disc diffusion method. The compounds IVd, IVe, Vd, and Ve exhibited moderate antifungal activities, whereas compounds IVb, IVc, Vb, and Vc showed prominent antifungal activities. Â
Designing and Training of Lightweight Neural Networks on Edge Devices using Early Halting in Knowledge Distillation
Automated feature extraction capability and significant performance of Deep
Neural Networks (DNN) make them suitable for Internet of Things (IoT)
applications. However, deploying DNN on edge devices becomes prohibitive due to
the colossal computation, energy, and storage requirements. This paper presents
a novel approach for designing and training lightweight DNN using large-size
DNN. The approach considers the available storage, processing speed, and
maximum allowable processing time to execute the task on edge devices. We
present a knowledge distillation based training procedure to train the
lightweight DNN to achieve adequate accuracy. During the training of
lightweight DNN, we introduce a novel early halting technique, which preserves
network resources; thus, speedups the training procedure. Finally, we present
the empirically and real-world evaluations to verify the effectiveness of the
proposed approach under different constraints using various edge devices.Comment: 13 pages, 7 figures, 11 table
A study of toxicity and differential gene expression in murine liver following exposure to anti-malarial drugs: amodiaquine and sulphadoxine-pyrimethamine
BACKGROUND: Amodiaquine (AQ) along with sulphadoxine-pyrimethamine (SP) offers effective and cheaper treatment against chloroquine-resistant falciparum malaria in many parts of sub-Saharan Africa. Considering the previous history of hepatitis, agranulocytosis and neutrocytopenia associated with AQ monotherapy, it becomes imperative to study the toxicity of co-administration of AQ and SP. In this study, toxicity and resulting global differential gene expression was analyzed following exposure to these drugs in experimental Swiss mice. METHODS: The conventional markers of toxicity in serum, oxidative stress parameters in tissue homogenates, histology of liver and alterations in global transcriptomic expression were evaluated to study the toxic effects of AQ and SP in isolation and in combination. RESULTS: The combination therapy of AQ and SP results in more pronounced hepatotoxicity as revealed by elevated level of serum ALT, AST with respect to their individual drug exposure regimen. Furthermore, alterations in the activity of major antioxidant enzymes (glutathione peroxidase, superoxide dismutase, catalase, glutathione reductase), indicating the development of oxidative stress, was more significant in AQ+SP combination therapy. cDNA microarray results too showed considerably more perturbed gene expression following combination therapy of AQ and SP as compared to their individual drug treatment. Moreover, a set of genes were identified whose expression pattern can be further investigated for identifying a good biomarker for potential anti-malarial hepatotoxicity. CONCLUSION: These observations clearly indicate AQ+SP combination therapy is hepatotoxic in experimental Swiss mice. Microarray results provide a considerable number of potential biomarkers of anti-malarial drug toxicity. These findings hence will be useful for future drug toxicity studies, albeit implications of this study in clinical conditions need to be monitored with cautions
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