Data Analytics of an Information System Based on a Markov Decision Process and a Partially Observable Markov Decision Process

Data analytics of an information system is conducted based on a Markov decision process(MDP)and a partially observable Markov decision process(POMDP)in this paper.Data analytics over a finite planning horizon and an infinite planning horizon for a discounted MDP is performed,respectively.Value iteration(VI),policy iteration(PI),and Q-learning are utilized in the data analytics for a discounted MDP over an infinite planning horizon to evaluate the validity of the MDP model.The optimal policy to minimize the total expected cost of states of the information system is obtained based on the MDP.In the analytics for a discounted POMDP over an infinite planning horizon of the information system,the effects of various parameters on the total expected cost of the information system are studied.

H_∞ Synchronization of Chaotic Systems via Delayed Feedback Control

The H∞ synchronization problem for a class of delayed chaotic systems with external disturbance is investigated. A novel delayed feedback controller is established under which the chaotic master and slave systems are synchronized with a guaranteed H∞ performance. Based on the Lyapunov stability theory, a delay-dependent condition is derived and formulated in the form of linear matrix inequality （LMI）. A numerical simulation is also presented to validate the effectiveness of the developed theoretical results.

D-S Evidence Theory Based Trust Ant Colony Routing in WSN

This paper proposes a trust ant colony routing algorithm by introducing a node trust evaluation model based on the D-S evidence theory into the ant colony routing protocol to improve the security of wireless sensor networks. To reduce the influence of conflict evidences caused by malicious nods, the consistent intensity is introduced to preprocess conflict evidences before using the D-S combination rule to improve the reliability of the D-S based trust evaluation. The nodes with high trust values will be selected as the routing nodes to insure the routing security, and the trust values are used as heuristic functions of the ant colony routing algorithm. The simulation tests are conducted by using the network simulator NS2 to observe the outcomes of performance metrics of packets loss rate and average end-to-end delay etc. to indirectly evaluate the security issue under the attack of inside malicious nodes. The simulation results show that the proposed trust routing algorithm can efficiently resist malicious attacks in terms of keeping performances of the average end-to-end delay, the throughtput and the routing packet overhead under attacking from malicious nodes.

Freestanding region-responsive bilayer for functional packaging of ingestible devices

Ingestible capsules have the potential to become an attractive alternative to traditional means of treating and detecting gastrointestinal(GI)disease.As device complexity increases,so too does the demand for more effective capsule packaging technologies to elegantly target specific GI locations.While pH-responsive coatings have been traditionally used for the passive targeting of specific GI regions,their application is limited due to the geometric restrictions imposed by standard coating methods.Dip,pan,and spray coating methods only enable the protection of microscale unsupported openings against the harsh GI environment.However,some emerging technologies have millimeter-scale components for performing functions such as sensing and drug delivery.To this end,we present the freestanding region-responsive bilayer(FRRB),a packaging technology for ingestible capsules that can be readily applied for various functional ingestible capsule components.The bilayer is composed of rigid polyethylene glycol(PEG)under a flexible pH-responsive Eudragit®FL 30 D 55,which protects the contents of the capsule until it arrives in the targeted intestinal environment.The FRRB can be fabricated in a multitude of shapes that facilitate various functional packaging mechanisms,some of which are demonstrated here.In this paper,we characterize and validate the use of this technology in a simulated intestinal environment,confirming that the FRRB can be tuned for small intestinal release.We also show a case example where the FRRB is used to protect and expose a thermomechanical actuator for targeted drug delivery.

A Historical Perspective on Development of Systems Engineering Discipline:A Review and Analysis

Since its inception,Systems Engineering(SE)has developed as a distinctive discipline,and there has been significant progress in this field in the past two decades.Compared to other engineering disciplines,SE is not affirmed by a set of underlying fundamental propositions,instead it has emerged as a set of best practices to deal with intricacies stemming from the stochastic nature of engineering complex systems and addressing their problems.Since the existing methodologies and paradigms(dominant patterns of thought and concepts)of SE are very diverse and somewhat fragmented.This appears to create some confusion regarding the design,deployment,operation,and application of SE.The purpose of this paper is 1)to delineate the development of SE from 1926-2017 based on insights derived from a histogram analysis,2)to discuss the different paradigms and school of thoughts related to SE,3)to derive a set of fundamental attributes of SE using advanced coding techniques and analysis,and 4)to present a newly developed instrument that could assess the performance of systems engineers.More than Two hundred and fifty different sources have been reviewed in this research in order to demonstrate the development trajectory of the SE discipline based on the frequency of publication.

3D-Printed electrochemical sensor-integrated transwell systems

This work presents a 3D-printed,modular,electrochemical sensor-integrated transwell system for monitoring cellular and molecular events in situ without sample extraction or microfluidics-assisted downstream omics.Simple additive manufacturing techniques such as 3D printing,shadow masking,and molding are used to fabricate this modular system,which is autoclavable,biocompatible,and designed to operate following standard operating protocols(SOPs)of cellular biology.Integral to the platform is a flexible porous membrane,which is used as a cell culture substrate similarly to a commercial transwell insert.Multimodal electrochemical sensors fabricated on the membrane allow direct access to cells and their products.A pair of gold electrodes on the top side of the membrane measures impedance over the course of cell attachment and growth,characterized by an exponential decrease(~160%at 10Hz)due to an increase in the double layer capacitance from secreted extracellular matrix(ECM)proteins.Cyclic voltammetry(CV)sensor electrodes,fabricated on the bottom side of the membrane,enable sensing of molecular release at the site of cell culture without the need for downstream fluidics.Real-time detection of ferrocene dimethanol injection across the membrane showed a three order-of-magnitude higher signal at the membrane than in the bulk media after reaching equilibrium.This modular sensor-integrated transwell system allows unprecedented direct,real-time,and noninvasive access to physical and biochemical information,which cannot be obtained in a conventional transwell system.

Electrochemical measurement of serotonin by Au-CNT electrodes fabricated on microporous cell culture membranes

Gut–brain axis(GBA)communication relies on serotonin(5-HT)signaling between the gut epithelium and the peripheral nervous system,where 5-HT release patterns from the basolateral(i.e.,bottom)side of the epithelium activate nerve afferents.There have been few quantitative studies of this gut-neuron signaling due to a lack of real-time measurement tools that can access the basolateral gut epithelium.In vitro platforms allow quantitative studies of cultured gut tissue,but they mainly employ offline and endpoint assays that cannot resolve dynamic molecular-release patterns.Here,we present the modification of a microporous cell culture membrane with carbon nanotube-coated gold(Au-CNT)electrodes capable of continuous,label-free,and direct detection of 5-HT at physiological concentrations.Electrochemical characterization of single-walled carbon nanotube(SWCNT)-coated Au electrodes shows increased electroactive surface area,5-HT specificity,sensitivity,and saturation time,which are correlated with the CNT film drop-cast volume.Two microliters of CNT films,with a 10-min saturation time,0.6μA/μM 5-HT sensitivity,and reliable detection within a linear range of 500 nM–10μM 5-HT,can be targeted for high-concentration,high-time-resolution 5-HT monitoring.CNT films(12.5μL)with a 2-h saturation time,4.5μA/μM 5-HT sensitivity,and quantitative detection in the linear range of 100 nM–1μM can target low concentrations with low time resolution.These electrodes achieved continuous detection of dynamic diffusion across the porous membrane,mimicking basolateral 5-HT release from cells,and detection of cell-released 5-HT from separately cultured RIN14B cell supernatant.Electrode-integrated cell culture systems such as this can improve in vitro molecular detection mechanisms and aid in quantitative GBA signaling studies.