Mobile Module Research Articles

Suspended 2D Material Biosensor for Reliable Sensing

TMDs such as MoS2 is playing an important role in the field of FETs, photodetectors, thin film transistors and efficient biosensors because of their direct band-gap, high mobility, and biocompatibility. Despite these strengths, the performance and reliability of such atomic layer are easily influenced by supporting substrate. Interaction between the supporting substrate and MoS2 implies that interface control is vital for performance of devices consisting of monolayer MoS2. In particular, the Silicon dioxide (SiO2) supporting substrate has an uneven morphology and is chemically active because of trapped environmental gases, unknown functional groups, chemical adsorbates, and charges. Thus, adding another layer of MoS2 on the top of SiO2 cannot contribute charge transport clearly, which leads to the unreliable function of every single device. To solve the interface problem, suspended 2D layer devices have been reported by wet etching silicon di oxide underneath the monolayer. Freestanding MoS2 has shown 10 times greater back gate electronic mobility than the supporting on the SiO2 substrate, which is ~0.9 cm2/Vs [1]. However, the existing SiO2 requires hazardous chemical etchants such as hydrofluoric acid (HF), which is difficult to handle and affects the 2D film structure and purity [2]. Secondly, freestanding MoS2 sags between the two electrodes because of the high spacing (~ 2 µm), which makes it impossible to coat another layer such as hafnium oxide (HfO2) and antibodies on top of monolayer. Therefore, this structure impedes making top gate FET biosensors, which allows for only back gating. However, back gate mobility is far lesser than the top gate mobility which hinders making a highly sensitive FET-based biosensor because the sensitivity of a sensor depends on its mobility [3]. Moreover, when linkers/antibodies are directly attached to the bare channel, the transduction mechanism is the combination of the electrostatic gating, direct charge transfer and mobility modulation. Therefore, it is desirable to eliminate the density of defects by covering the bare channel material with insulating material and then functionalizing linkers and antibodies on the top of the insulator [3, 4]. In this work, CVD grown MoS2 channel material is transferred on self-assembled photolithographically patterned nano-gaps to achieve suspension and is covered with HfO2 to eliminate the direct functionalization of channel material. These nano-gap arrays provide mechanical strength to the monolayer and do not allow the supporting substrate to touch after coating another thin insulating layer as well as linkers/antibodies. HfO2 can be easily functionalized by linkers (Benzene 1, 4 dithiols) and antibodies (E-coli antibodies) to bring variation to the suspended 2D material by targeting a charged biomolecule (E-coli). In addition, termination of the supporting substrate leads to increments of electron mobility which are directly proportional to the sensitivity of the FET biosensor. The proposed FET biosensor has the capability to detect one molecule because of its single atomic layer as a channel material, its scalability due to the involvement of optical photolithography, and its fast response because of higher mobility. References Jin, T., et al., Suspended single-layer MoS2 devices. Journal of Applied Physics, 2013. 114(16): p. 164509.Zhang, F., et al., Etchant-free transfer of 2D nanostructures. Nanotechnology, 2017. 29(2): p. 025602.Sarkar, D., et al., MoS2 field-effect transistor for next-generation label-free biosensors. ACS nano, 2014. 8(4): p. 3992-4003.Kalantar-zadeh, K. and J.Z. Ou, Biosensors based on two-dimensional MoS2. ACS Sensors, 2015. 1(1): p. 5-16.

An Adaptive Mobile Health System to Support Self-Management for Persons With Chronic Conditions and Disabilities: Usability and Feasibility Studies.

BackgroundPersons with chronic conditions and disabilities (PwCCDs) are vulnerable to secondary complications. Many of these secondary complications are preventable with proactive self-management and proper support. To enhance PwCCDs' self-management skills and conveniently receive desired support, we have developed a mobile health (mHealth) system called iMHere. In 2 previous clinical trials, iMHere was successfully used to improve health outcomes of adult participants with spina bifida and spinal cord injury. To further expand use of iMHere among people with various types of disabilities and chronic diseases, the system needs to be more adaptive to address 3 unique challenges: 1) PwCCDs have very diverse needs with regards to self-management support, 2) PwCCDs’ self-management needs may change over time, and 3) it is a challenge to keep PwCCDs engaged and interested in long-term self-management.ObjectiveThe aim of this study was to develop an adaptive mHealth system capable of supporting long-term self-management and adapting to the various needs and conditions of PwCCDs.MethodsA scalable and adaptive architecture was designed and implemented for the new version, iMHere 2.0. In this scalable architecture, a set of mobile app modules was created to provide various types of self-management support to PwCCDs with the ability to add more as needed. The adaptive architecture empowers PwCCDs with personally relevant app modules and allows clinicians to adapt these modules in response to PwCCDs’ evolving needs and conditions over time. Persuasive technologies, social support, and personalization features were integrated into iMHere 2.0 to engage and motivate PwCCDs and support long-term usage. Two initial studies were performed to evaluate the usability and feasibility of the iMHere 2.0 system.ResultsThe iMHere 2.0 system consists of cross-platform client and caregiver apps, a Web-based clinician portal, and a secure 2-way communication protocol for providing interactions among these 3 front-end components, all supported by a back-end server. The client and caregiver apps have 12 adaptive app modules to support various types of self-management tasks. The adaptive architecture makes it possible for PwCCDs to receive personalized app modules relevant to their conditions with or without support from various types of caregivers. The personalization and persuasive technologies in the architecture can be used to engage PwCCDs for long-term usage of the iMHere 2.0 system. Participants of the usability study were satisfied with the iMHere 2.0 client app. The feasibility evaluation revealed several practical issues to consider when implementing the system on a large scale.ConclusionsWe developed an adaptive mHealth system as a novel method to support diverse needs in self-management for PwCCDs that can dynamically change over time. The usability of the client app is high, and it was feasible for PwCCDs to use in supporting personalized and evolving self-care needs.

Electronic structure, carrier mobility and strain modulation of CH (SiH, GeH) nanoribbons

Using first-principles calculations coupled with deformation potential (DP) theory, we have systematically studied the band structure, carrier mobility and strain modulation of monolayer graphane (CH), silicane (SiH) and germanane (GeH) nanoribbons. It is found that all the CH (SiH, GeH) nanoribbons are semiconductor with a wide range of band gap. The carrier mobility results show that the armchair germanane nanoribbon (AGeNR) has the characteristic of p -type semiconductor in electrical conduction because its hole mobility is larger than the electron mobility. While the graphane nanoribbon (CNR) behaves as n-type semiconductor in electrical conduction. Compared to AGeNR and CNR, the mobilities of other nanoribbons are much smaller. Moreover, the band structure and carrier mobility of AGeNR and CNR can be effectively tuned by strain. There are different state competing for the valence band maximum (VBM). When the strain exceeds certain value, the VBM is transited to a new band-edge state accompanied with a large increase of hole mobility. The new band-edge state has smaller DP constant because its bond character makes it less sensitive to strain, and thus resulting in higher hole mobility.

Monitoring Structural Transitions in RNA Polymerase using Single Molecule FRET

Structural transitions in protein machines play a central role in their function. Such motions can be studied in great detail and in real-time using the method of single-molecule FRET (smFRET); however, the use of smFRET in visualizing protein motions has been limited by a lack of strategies for site-specific labeling of mobile protein modules. To address this challenge, we have developed methods for site-specific introduction of fluorescent probes into proteins such as the bacterial RNA polymerase (RNAP); the methods are highly selective and combine unnatural-amino-acid mutagenesis and bio-orthogonal labeling. We combine this breakthrough with smFRET on surface-immobilized molecules and look at conformational change of a large structural domain in the RNAP, “β clamp”. For the first time, we show directly that the clamp is highly dynamic, visiting three conformations. We also show that some antibiotics that target RNAP function by locking clamp into specific conformations; further, we discovered that a major stress-response factor (ppGpp) functions by modulating clamp dynamics. We then employed a similar strategy to a more difficult target, a less than 45 amino acid motif, “trigger loop” (TL), which is very close to the active center of RNAP. We succeeded in producing a fully functional TL-labeled RNAP and used smFRET to show directly that binding of correct NTP at the active site induces TL closure and that the TL ensures substrate specificity. Finally, we show using a real-time assay that TL opens and closes in each nucleotide addition cycle. Our strategies are general and provide insight into functioning of large multi-subunit protein machines.

High-performance RF Switch in 0.13 μm RF SOI process

A high-performance single-pole single-throw (SPST) RF switch for mobile phone RF front-end modules (FEMs) was designed and characterized in a 0.13 μm partially depleted silicon-on-insulator (PD SOI) process. In this paper, the traditional series-shunt configuration design was improved by introducing a suitably large DC bias resistor and leakage-preventing PMOS, together with the floating body technique. The performance of the RF switch is greatly improved. Furthermore, a new Ron × Coff testing method is also proposed. The size of this SPST RF switch is 0.2 mm2. This switch can be widely used for present 4G and forthcoming 5G mobile phone FEMs.

Demand side management in smart grid: A laboratory-based educational perspective

Demand side management is an important operational aspect of smart grid focusing on cost and efficiency optimisation by load management and control. With growing power demand and shortage of energy resources, it is necessary to educate people on the benefits of demand side management. In the present Electrical Engineering curriculum, demand side management is also being taught as a core topic in power system courses. Hands-on laboratory sessional in demand side management will definitely assist the students in their understanding of the working principles and implementation challenges of demand side management. In this paper, a small-scale laboratory prototype demand side management system has been implemented and is being used in power system laboratory work for Electrical Engineering students at IIT Bhubaneswar (India). In this demand side management prototype system, a Central Energy Management Unit, interfaced with all load/energy control units at each customer end, is used for centralised load scheduling control. A data-entry circuit is used at each customer end for prior transmission of load scheduling request. For wireless data communication among various units, a Global System for Mobile communication is adopted. The laboratory setup consists of few loads, ARDUINO microcontrollers, relay modules, current sensors, MATLAB interface (at Central Energy Management Unit end) and Global System for Mobile communication modules. The learning performance/efficiency of the students has been evaluated by the students’ responses to a questionnaire before and after the experiment being conducted by them and it has been found to be noteworthy highlighting the educative efficacy of the well-designed experiment on demand side management.

Modulation of the electroosmotic mobility using polyelectrolyte multilayer coatings for protein analysis by capillary electrophoresis

Successive multiple ionic-polymer layers (SMIL) coatings have been often used in capillary electrophoresis due to their simplicity to implement and regenerate. However, the performances of the separation are strongly dependent on the nature of the polyelectrolyte partners used to build the SMIL coating. In this work, we investigate new couples of polyelectrolytes that were not tested before: namely, polybrene (PB), quaternized diethylaminoethyl dextran (DEAEDq) and ε-poly(lysine) (ε-PLL), as polycations, in combination with poly(acrylic acid), dextran sulfate, poly(styrenesulfonate), poly(methacrylic acid) and poly(l-lysine citramide), as polyanions. Systematic study of intra- and inter-capillaries repeatabilities/reproducibilities was performed based on the determination of migration time, separation efficiency and electroosmotic mobility. Interestingly, the electroosmotic flow was found to vary with the nature of the polycation on a broad range of electroosmotic mobility decreasing in magnitude in the order of PB>ε-PLL > DEAEDq, whatever the polyanion associated. Application of the coatings to the separation of proteins is illustrated in a 0.5 M acetic acid BGE, including CE-MS separation of ribonuclease B-glycoforms of the same mass (positional or structural isomers).

Standardization of building technology on demand via robotic

Although the basic installation arrangement and sequence within Technical Building Equipment, based on generation, distribution and transfer of energy quantities, has remained virtually unchanged for some time, this essentially grid-connected world of installations could soon change significantly for different reasons. This feasibility study presents an almost disruptive approach, based on mobile multifunctional, chargeable and unchargeable PCM-TGA robot technology, which should be able to perform room conditioning (esp. heating, room air quality) as well as room monitoring in at least two rooms via a mobile module. Charging takes place at a plug and play transfer station, e.g. via a decentralized heat pump system integrated in the brickwork. First, the authors show the transdisciplinary reasons, which are essentially socio-politically evidence-based, for the need for additive technological development. Then, both the overall system that consists of a decentralized plug-and-play heat pump transfer station integrated in the brickwork and a mobile robotized heat distribution system, which is not tied to a pipe system, are explained. Based on an exemplary floor plan, living areas will then be shown that require permanent conditioning as well as those that can have discontinuous conditioning via the robot. Feasibility is demonstrated by means of building simulation of the load profiles, leading to appropriate storage dimensioning using a suitable phase change material. Here the authors refer to their extensive theoretical and experimental knowledge in handling dynamic PCMs when creating a prototype. Finally, the technological approach undergoes a critical assessment.

Insulation systems for extreme conditions

Abstract The article devoted to the questions of developing effective insulation sheath for extreme temperature conditions. In terms of resistance to low and alternating temperatures, tensile strength and water absorption, polyethylene foam insulating shells are quite applicable to insulation systems. The article contains the experience of usage of seamless polyethylene shells in stationary and mobile residential modules operated in the Arctic region and in insulation systems based on the principle of “thermal blanket” for preservation of snow used at ski resorts, when stored snow is covered with rolled polyethylene foam with a mechanical connection of sheets with a subsequent awning coating.

PMMA-Coated Capacitive Type Soil Moisture Sensor: Design, Fabrication, and Testing

This paper describes the fringing electric field modeling and performance of four different shaped poly methyl methacrylate-coated capacitive sensors for soil moisture measurement. Experiments are carried out in the laboratory by placing the sensor inside the soil. The analytical solution for such fringing field system is difficult to obtain, so COMSOL Multiphysics software is used for modeling the capacitive sensor surrounded by the soil. Experimental data are compared with the software simulated value. Statistical root-mean-square error (RMSE) and percentage of normalized RMSE for polynomial fit are studied for the sensitivity and performance analysis. Effect of external temperature on the performance of the sensor is also discussed. The proposed signal conditioning circuit is implemented in printed circuit board to measure the output voltage with respect to capacitance change. Obtained results are transmitted through a global system for mobile communication module for remote observation of soil moisture. The thermogravimetric method is used for voltage to soil moisture calibration, and based on the experimental data, results are analyzed further. A review of some relevant fringing field capacitive sensors and their instrumentation system reported in past 7-8 years are studied for comparison with the proposed sensor system.

An Edge-Based Architecture to Support Efficient Applications for Healthcare Industry 4.0

Edge computing paradigm has attracted many interests in the last few years as a valid alternative to the standard cloud-based approaches to reduce the interaction timing and the huge amount of data coming from Internet of Things (IoT) devices toward the Internet. In the next future, Edge-based approaches will be essential to support time-dependent applications in the Industry 4.0 context; thus, the paper proposes BodyEdge , a novel architecture well suited for human-centric applications, in the context of the emerging healthcare industry. It consists of a tiny mobile client module and a performing edge gateway supporting multiradio and multitechnology communication to collect and locally process data coming from different scenarios; moreover, it also exploits the facilities made available from both private and public cloud platforms to guarantee a high flexibility, robustness, and adaptive service level. The advantages of the designed software platform have been evaluated in terms of reduced transmitted data and processing time through a real implementation on different hardware platforms. The conducted study also highlighted the network conditions (data load and processing delay) in which BodyEdge is a valid and inexpensive solution for healthcare application scenarios.

SVS-JOIN: Efficient Spatial Visual Similarity Join for Geo-Multimedia

In the big data era, massive amount of multimedia data with geo-tags has been generated and collected by smart devices equipped with mobile communications module and position sensor module. This trend has put forward higher request on large-scale geo-multimedia retrieval. Spatial similarity join is one of the significant problems in the area of spatial database. Previous works focused on spatial textual document search problem, rather than geo-multimedia retrieval. In this paper, we investigate a novel geo-multimedia retrieval paradigm named spatial visual similarity join (SVS-JOIN for short), which aims to search similar geo-image pairs in both aspects of geo-location and visual content. Firstly, the definition of SVS-JOIN is proposed and then we present the geographical similarity and visual similarity measurement. Inspired by the approach for textual similarity join, we develop an algorithm named SVS-JOIN $_{B}$ by combining the PPJOIN algorithm and visual similarity. Besides, an extension of it named SVS-JOIN $_{G}$ is developed, which utilizes spatial grid strategy to improve the search efficiency. To further speed up the search, a novel approach called SVS-JOIN $_{Q}$ is carefully designed, in which a quadtree and a global inverted index are employed. Comprehensive experiments are conducted on two geo-image datasets and the results demonstrate that our solution can address the SVS-JOIN problem effectively and efficiently.

Access Control, Fire Prevention and Surveillance Security System

This system is designed to detect intruders, gas leakages as well as to serve as a surveillance system. This work focuses on the development of a reliable access control and fire prevention system synergized with surveillance system. In developing the system, Passive Infrared (PIR) sensors, gas sensor, buzzer, Global System Mobile (GSM) module, Liquid Crystal Display (LCD) and RGB Light Emitting Diode (LED) were connected to an Arduino Mega microcontroller. Fingerprint module and keypad were connected to Arduino Nano for access control. For the surveillance system, a 3D camera was connected to the PC to view the screen of the LCD and surroundings of a building with the aid of a Yaw am, Many Cam, Mirror OP and Google Remote Desktop (RDP). In addition, the system also contains Light Dependent Resistor (LDR) which turns ON in the dark and OFF when there is light. The performance evaluation of the system was carried out through the rate of access allowed correctly and access denied incorrectly, accuracy as well as the precision. The result showed 71.8% efficiency for positive access allowed rate and 28.2% false access denied rate. The practical application of this system is that it can be adopted at home and industrial environment as an efficient means of controlling intruders, fire-outbreak as well as serving as a surveillance system.

Synergistic modulation of mobility and thermal conductivity in (Bi,Sb)2Te3 towards high thermoelectric performance

Two-step sintering efficiently enhances zT by tuning the microstructure in a wide range from atomic defects to micrometer second phase.

Development of Modular Cable-Driven Parallel Robotic Systems

Task-oriented modular design and safety monitoring are demonstrated to be outstanding challenges for robots in practical application. In order to obtain better flexibility and better obstacles avoidance capability, design and analysis of a modular cable-driven parallel robot (MCDPR) are presented in this paper, which can be reconfigured to several configurations in engineering applications by changing the number of the mobile modules and the connection mode of the end effector. With regard to the motion control and safety monitoring system, the design and implementation of hardware and software are presented. An experimental prototype for the MCDPR is developed, followed by a brief illustration of the connection mode between the end effector and cables, and the installation of monitoring nodes. The performance of the MCDPR is discussed experimentally, including real-time pose monitoring and obstacle avoidance. The results verify the feasibility and efficiency of kinematics model and obstacle avoidance method, and the results also indicate that the designed motion control and safety monitoring system can realize trajectory tracking control, real-time safety monitoring, and obstacle avoidance for the MCDPR.

Mathematical Model of the Controlled Object when Regulating the Working Volume of the Manipulator Pump

This paper describes the constructed mathematical model of the controlled object of the automated system for controlling the displacement volume of the manipulator pump. The change in pump displacement volume is performed in order to save energy by minimizing the fluid drain through the overflow valve. The use of the considered manipulator is intended in the process of automated supply of blanks to the working area of a press used in forging and hot stamping processes. The reactive forces acting on the moving parts of the mobility modules from the fixed parts of the manipulator are determined. Conversion of the useful power of the pump into the useful power of hydraulic motors is performed. This takes into account the losses using efficiency. An equation describing the mathematical model of the controlled object is obtained. This equation is represented in relative variables. The derivation of this equation and the determination of the reactive forces are made on the basis of the assumption that all transport degrees of freedom are translational. This limitation is caused by the peculiarities of the working area of the press used in technological processes of forging and hot forming of blanks. The working zone is a deep horizontal tunnel, the movement of the working object in which is possible only with translational degrees of freedom.

DCas9-mediated Nanoelectrokinetic Direct Detection of Target Gene for Liquid Biopsy.

The-state-of-the-art bio- and nanotechnology have opened up an avenue to noninvasive liquid biopsy for identifying diseases from biomolecules in bloodstream, especially DNA. In this work, we combined sequence-specific-labeling scheme using mutated clustered regularly interspaced short palindromic repeats associated protein 9 without endonuclease activity (CRISPR/dCas9) and ion concentration polarization (ICP) phenomenon as a mechanism to selectively preconcentrate targeted DNA molecules for rapid and direct detection. Theoretical analysis on ICP phenomenon figured out a critical mobility, elucidating two distinguishable concentrating behaviors near a nanojunction, a stacking and a propagating behavior. Through the modulation of the critical mobility to shift those behaviors, the C-C chemokine receptor type 5 ( CCR5) sequences were optically detected without PCR amplification. Conclusively, the proposed dCas9-mediated genetic detection methodology based on ICP would provide rapid and accurate micro/nanofluidic platform of liquid biopsies for disease diagnostics.

Efficient region of visual interests search for geo-multimedia data

With the proliferation of online social networking services and mobile smart devices equipped with mobile communications module and position sensor module, massive amount of multimedia data has been collected, stored and shared. This trend has put forward higher request on massive multimedia data retrieval. In this paper, we investigate a novel spatial query named region of visual interests query (RoVIQ), which aims to search users containing geographical information and visual words. Three baseline methods are presented to introduce how to exploit existing techniques to address this problem. Then we propose the definition of this query and related notions at the first time. To improve the performance of query, we propose a novel spatial indexing structure called quadtree based inverted visual index which is a combination of quadtree, inverted index and visual words. Based on it, we design a efficient search algorithm named region of visual interests search to support RoVIQ. Experimental evaluations on real geo-image datasets demonstrate that our solution outperforms state-of-the-art method.

Research on the design of the independent-combinatorial mobile disaster emergency unit in the cold area

Through the study the existing problems of emergency medical space in severe cold region, and the existing mobile emergency medical space is based on two types of operation modes independent and combined, a mobile emergency medical space system with independent and combined operating mode is constructed.This study adopts the method of modular design, the overall functionality of a mobile emergency medical space, modules functions and components function separately, make the type of component used in a variety of modules, different modules constitute multiple system.In the domain of the sustainable design for mobile disaster response space, the goal is to make effective use of medical resources, improve rescue efficiency and improve treatment environment.

Predictability of Clinical Knowledge Through Mobile App-based Simulation for the Treatment of Pediatric Septic Arthritis: A Pilot Study.

Recently the American Board of Orthopaedic Surgery and the Accreditation Council of Graduate Medical Education have identified the treatment of septic arthritis of the hip in children as a milestone skill for all US orthopaedic residents. The purpose of this study was to test correlation between clinical knowledge and examination score on a mobile app-based training module for the treatment of pediatric septic hip arthritis. A 4-part simulation model on surgical decision-making associated with the treatment of pediatric septic arthritis was developed through expert consensus. Orthopaedic trainees participating in the "Top Gun" program of the 2015 and 2016 International Pediatric Orthopaedic Symposiums were recruited to participate in this pilot study. Trainees completed a presimulation quiz on their knowledge of diagnosis, arthrocentesis, and surgical irrigation and debridement on a pediatric patient presenting with septic arthritis of the hip. Trainees then completed the 4-part simulation on the mobile app. Pearson correlation analysis was used to assess the relationship between the quiz and the simulation. A total of 53 orthopaedic residents and fellows participated in the simulation. Median quiz score was 87 points [interquartile range (IQR), 81 to 94] before the intervention and 100 points (IQR, 94 to 100) postintervention. The median simulation test score was 89 (IQR, 81 to 92) which demonstrated a positive correlation with the postintervention quiz (r=0.44, P<0.001). The preintervention metrics demonstrated a positive correlation with postintervention metrics (r=0.53, P<0.001). This study revealed a statistically significant positive correlation between the mobile app simulation and the clinical knowledge of the participants, as well as the ability to improve knowledge about a procedure during the testing period. These findings support the ability for the mobile app to test clinical knowledge. In the current environment of decreased work hours and patient exposure for orthopaedic trainees, mobile app-based simulation has the potential to safely aid in assessment of orthopaedic residents and fellows.