Inherent Mismatch Research Articles

2359 - Pareto Optimality for Assessing Multimodal Transportation Accessibility: Balancing Equity and Efficiency When Sitting Interventions

Background Travel time as a proxy for spatial accessibility in health care location-allocation studies can be particularly relevant when spatially concentrated population have a repeating pattern of infections, or a shorter return interval for services. This travel time based accessibility study focuses on a population identified as having repeat sexually transmitted infections. This population has been shown to be strongly associated with low socioeconomic status, which often corresponds to substantive reliance on public transit. Public health intervention studies barely consider transit when quantifying accessibility. Moreover, common frameworks used in these studies mostly focus on efficient allocation of services and usually disregard equity issues. Methods This study proposes a Pareto optimality approach to recommend locations that are multimodal accessible and allow equitable and efficient access to services. A simulated at-risk population, drawn from known core areas of repeat sexually transmitted infections in Kalamazoo County, Michigan, is examined. A raster-based drive time and a transit time model were developed using ArcGIS. Bi-objective optimization models were then developed to balance efficiency (by minimizing average travel time of the cohort) and equity (by minimizing variations of travel time from all simulated households). Results This raster-based cost optimization approach successfully identifies potential locations that are efficiently and equitably accessible using different transportation modes. A range of alternative solutions (Pareto frontiers) spatially and statistically enable decision makers to select from multiple locations and assess acceptable limits to travel for a given population. In our example, choosing a location, T2 over T1 means reducing the average travel time by 2.19 minutes by conceding only 11.94% increase in standard deviation of travel time. Additionally, T2 reduces the average travel time by 8.91 minutes and standard deviation by 3.7 minutes when comparing to existing facility location. In general, the spatial area bounded by the minimum average and minimum standard deviation location for a frontier line would represent the constraints to intervention location. The area then becomes a usable metric to measure transit versus private vehicle accessibility. Conclusions Improving spatial access to health facilities is important in reducing the prevalence of disease. Therefore, multimodal accessibility should be emphasized in future intervention placement research. The analysis of individual's travel time from distinct households to facility locations helps to address the inherent mismatch between current statistical methods that require detection of significant densities and the reality of individuals located on a street network or constrained by a particular transportation modality.

Monolithic Airflow Detection Chip With Automatic DC Offset Calibration

A monolithic airflow detection chip is proposed for respiration rate monitoring, and it integrates MEMS sensors with their CMOS signal processing circuits into a single chip. In fact, one major issue of integrating resistive MEMS sensors with CMOS circuits is how to deal with the dc offset caused by the inherent resistance mismatches in the sensors. In this paper, an airflow detection chip with automatic dc offset calibration is proposed. Moreover, there are two MEMS cantilever-based sensors, metal-covered and metal-free, in the proposed chip. The metal-covered sensor was designed for validating the MEMS simulation results of CoventorWare, while the metal-free sensor has a higher sensitivity and better performance. According to the measured results, the pressure sensitivity of the metal-covered sensor is $1.3\times 10^{5}~\mu \text{m}^{3}$ /mN, which is in the same order with the CoventorWare simulation result, and the sensitivity of the metal-free sensor is $3.2\times 10^{5}~\mu \text{m}^{3}$ /mN. As to the fully built-in CMOS signal processing circuits, the system bandwidth is 0.5–4 Hz, and the input dc offset can be attenuated by a factor of 10 dB. The proposed chip was designed using a 0.35- $\mu \text{m}$ CMOS/MEMS 2P4M mixed-signal polycide process, and the chip area is $1.80\times2.35$ mm2.

Obsolete Ideologies for the Knowledge Based Creative Economy: Essential Next Steps for Innovative Classroom Practices

There is an inherent mismatch between the prevailing individualistic narrative implicit within the 20th century education gospel of higher skills equals better jobs equals a better economy, and the realities of the emerging knowledge based creative economy where precarious, part-time labour persists and outsourcing of employment globally is compounded. Before broad implementation of innovative approaches within classrooms can be realized, underlying ideologies that have shaped and continue to shape education systems and policy must be surfaced and challenged, taking seriously the shifting employment landscape and social context in the enigmatic digital era.

Dynamic mismatch losses of grid-connected PV-battery systems in residential buildings

Battery energy storage devices coupled with photovoltaic (PV) systems have to react to the fluctuating nature of the PV output and electrical demand in residential buildings. However, the charging and discharging power cannot be adjusted to the power fluctuations without any time delay so that an inherent temporal mismatch between the battery power and the residual power (PV output minus load) occurs under dynamic conditions. This paper presents a simulation study analyzing the response time-induced mismatch losses of grid-connected PV-battery systems. Firstly, the response time issue is analyzed theoretically to reveal how the energy flows between the household and the grid are changed due to the delayed battery response. Then, measurements are presented to show the dynamic behavior of two different PV-battery systems. The experimental results reveal settling times of up to 7 s to reach the steady state after an abrupt step change in the load demand. Thirdly, simulations of an AC-coupled PV-battery system are carried out with a time step size of 1 s. A sensitivity analysis is conducted to identify the impact of the dynamic response on the annual amount of energy exchanged with the grid. It is found that longer response times are accomplished by an increase in the grid feed-in and grid supply as well. Consequently, a slow-reacting battery system diminishes the economic benefit for the owner of the PV-battery system. In order to improve the transparency from the end-customeŕs point of view, response time-related specifications should be stated in the data sheets of the products in the future.

Air and its Sonographic Appearance: Understanding the Artifacts

BackgroundAlthough air has traditionally been considered a barrier to sonographic imaging, when encountered in unusual settings it can serve as an important indicator of various pathologic states as well. Clinician recognition and thorough understanding of the characteristic pattern of artifacts generated by air are critical for making a number of important diagnoses. Case SeriesWe present five emergency department cases in which air was visualized in a pathologic location. Pneumothorax, pneumoperitoneum, necrotizing fasciitis, or Fournier's gangrene, and subcutaneous emphysema and pneumomediastinum, can be rapidly and easily identified on ultrasound by the presence of air artifacts. The relevant sonographic findings are described and discussed in this article. Why Should an Emergency Physician Be Aware of This?Due to its inherent impedance mismatch with other human tissues, air has a characteristic appearance on ultrasound that includes irregular hyperechoic structures, “dirty shadowing,” A-lines, and decreased visualization of deeper structures. Knowledge of the sonographic appearance of air artifacts can assist the physician in making a diagnosis, selecting appropriate additional imaging, and enlisting specialist consultation.

Electron transfer dynamics in fuel producing photosystems

An often overlooked aspect of solar fuel production is the inherent mismatch between bulk charge carrier lifetimes and rates of charge transfer reactions. Considering water oxidation, interfacial charge transfer occurs on the millisecond to second timescales while bulk charge carrier lifetimes of metal oxides are typically in the fast picosecond–nanosecond regime. For charge transfer to efficiently compete with charge recombination, strategies that substantially increase the charge carrier lifetime need to be applied. In this chapter, we discuss the magnitude of the kinetic mismatch, overview common effective charge separation strategies that address this mismatch and highlight recent developments in our understanding of these processes. We also touch upon recent advances in determining the chemical nature of key reaction intermediates.

The arc of Mass Spectrometry Exchange Formats is long, but it bends toward HDF5.

The evolution of data exchange in Mass Spectrometry spans decades and has ranged from human‐readable text files representing individual scans or collections thereof (McDonald et al., 2004) through the official standard XML‐based (Harold, Means, & Udemadu, 2005) data interchange standard (Deutsch, 2012), to increasingly compressed (Teleman et al., 2014) variants of this standard sometimes requiring purely binary adjunct files (Römpp et al., 2011). While the desire to maintain even partial human readability is understandable, the inherent mismatch between XML's textual and irregular format relative to the numeric and highly regular nature of actual spectral data, along with the explosive growth in dataset scales and the resulting need for efficient (binary and indexed) access has led to a phenomenon referred to as “technical drift” (Davis, 2013). While the drift is being continuously corrected using adjunct formats, compression schemes, and programs (Röst et al., 2015), we propose that the future of Mass Spectrometry Exchange Formats lies in the continued reliance and development of the PSI‐MS (Mayer et al., 2014) controlled vocabulary, along with an expedited shift to an alternative, thriving and well‐supported ecosystem for scientific data‐exchange, storage, and access in binary form, namely that of HDF5 (Koranne, 2011). Indeed, pioneering efforts to leverage this universal, binary, and hierarchical data‐format have already been published (Wilhelm et al., 2012; Rübel et al., 2013) though they have under‐utilized self‐description, a key property shared by HDF5 and XML. We demonstrate that a straightforward usage of plain (“vanilla”) HDF5 yields immediate returns including, but not limited to, highly efficient data access, platform independent data viewers, a variety of libraries (Collette, 2014) for data retrieval and manipulation in many programming languages and remote data access through comprehensive RESTful data‐servers. © 2016 The Authors. Mass Spectrometry Reviews published by Wiley Periodicals, Inc. Mass Spec Rev 36:668–673, 2017

Bank Capital Structure and Financial Innovation: Antagonists or Two Sides of the Same Coin?

This article examines the challenges to banking capital regulation posed by ongoing financial innovation through regulatory capital arbitrage (RCA). On the one hand, such practice undermines the quality of regulatory capital, eroding prudential capital standards, but most importantly it creates a distortion in the regulatory capital ratio measures, which prevents investors and regulators from identifying the bank’s real underlying risks. Opportunities for RCA arise as a consequence of the inherent mismatch of accounting goals, corporate law, and prudential regulation—all interacting with the notion of capital for banks. On the other hand, financial innovation is the result of banks’ risk-management policies. In order to reduce the cost of capital and compliance, banks engage in derivatives, structured finance, and hybrid instruments, thus altering the risk/return of their cash flow and the information released to the market for disclosure. In a way, regulation is the solution but also part of the problem. Implementing too severe rules for capital and disclosure, as well as fair value measurement for financial reporting purposes, may result in strengthening regulatory capital standards and limiting the opportunities for arbitrage at the expense of constraining banks’ risk-management policies. To validate this hypothesis, the article examines three problematic areas for capital micro-prudential regulation: hybrid instruments and structured finance, assets valuation and provisioning, and disclosure. The analysis is integrated with an assessment of the same issues from the perspective of macro-prudential regulation. In relation to these areas, the article discusses the regulator’s approach and regulatory strategies implemented. Macro-prudential regulation is essential to reduce RCA. Basel III has created regulation based on a multiple metric system supported by a strengthened risk-weight capital ratio and a comprehensive legal framework for supervisor and resolution. While these legal frameworks provide constraints that mutually reinforce prudent behaviour, it is important to point out that the regulation has to be functional for the market under examination in order to strike the right balance between regulatory flexibility and robust, enforceable standards.

A Practical Method for High‐Resolution Embedded Liquid Surfaces

AbstractCombining high‐resolution level set surface tracking with lower resolution physics is an inexpensive method for achieving highly detailed liquid animations. Unfortunately, the inherent resolution mismatch introduces several types of disturbing visual artifacts. We identify the primary sources of these artifacts and present simple, efficient, and practical solutions to address them. First, we propose an unconditionally stable filtering method that selectively removes sub‐grid surface artifacts not seen by the fluid physics, while preserving fine detail in dynamic splashing regions. It provides comparable results to recent error‐correction techniques at lower cost, without substepping, and with better scaling behavior. Second, we show how a modified narrow‐band scheme can ensure accurate free surface boundary conditions in the presence of large resolution mismatches. Our scheme preserves the efficiency of the narrow‐band methodology, while eliminating objectionable stairstep artifacts observed in prior work. Third, we demonstrate that the use of linear interpolation of velocity during advection of the high‐resolution level set surface is responsible for visible grid‐aligned kinks; we therefore advocate higher‐order velocity interpolation, and show that it dramatically reduces this artifact. While these three contributions are orthogonal, our results demonstrate that taken together they efficiently address the dominant sources of visual artifacts arising with high‐resolution embedded liquid surfaces; the proposed approach offers improved visual quality, a straightforward implementation, and substantially greater scalability than competing methods.

Lattice Mismatch Dominant Yet Mechanically Tunable Thermal Conductivity in Bilayer Heterostructures.

Heterostructures that are assembled by interfacing two-dimensional (2D) materials offer a unique platform for the emerging devices with unprecedented functions. The attractive functions in heterostructures that are usually absent and beyond the single layer 2D materials are largely affected by the inherent lattice mismatch between layers. Using nonequilibrium molecular dynamics simulations, we show that the phonon thermal transport in the graphene-MoS2 bilayer heterostructure is reduced by the lattice mismatch, and the reduction can be mitigated well by an external tension, weakening the effect of inherent mismatch-induced strain on thermal conductivity. Mechanical analysis in each layered component indicates that the external tension will alleviate the lattice mismatch-induced deformation. The phonon spectra are also softened by the applied tension with a significant shift of frequency from high to low modes. A universal theory is proposed to quantitatively predict the role of the lattice mismatch in thermal conductivity of various bilayer heterostructures and shows good agreement with simulations.

Bank Capital Structure and Financial Innovation: Antagonists or Two Sides of the Same Coin?

This article examines the challenges to banking capital regulation posed by ongoing financial innovation through regulatory capital arbitrage. On the one hand, such practice undermines the quality of regulatory capital, eroding prudential capital standards, but most importantly it creates a distortion in the regulatory capital ratio measures, which prevents investors and regulators from identifying the bank’s real underlying risks. Opportunities for regulatory capital arbitrage arise as a consequence of the inherent mismatch of accounting goals, corporate law and prudential regulation – all interacting with the notion of capital for banks. On the other hand, financial innovation is the result of banks’ risk-management policies. In order to reduce the cost of capital and compliance banks engage in derivatives, structured finance and hybrid instruments, altering the risk/return of their cash flow and the information released to the market for disclosure. In a way, regulation is the solution but also part of the problem. For this reason, new regulation strategies for banks need to be implemented. Systemic risk and balance-sheet risk need to be tackled respectively with macro- and micro-prudential regulation. This would involve an international harmonization of the accounting standards and individualised capital adequacy requirements for banks. The regulation has to be functional for the market under examination. The regulator should therefore consider the adoption of prudential filters to make static variables such as accounting rules, which are normally focused on evaluation, more dynamic to give banks some financial flexibility in their risk-management policies.

SRAM-Based Unique Chip Identifier Techniques

Integrated circuit (IC) identification using unclonable digital fingerprints facilitates the authentication of ICs, device tracking, and cryptographic functions. In this paper, we present two hardware methods exploiting the inherent process-induced mismatch of SRAM cells. The proposed circuits improve upon those previously published by reducing the number of bits that vary from trial to trial, and can be used at times other than just IC power-up. The proposed circuits and methods are compared with the previous power-up approach using the experimental results from a 90-nm test chip. The required SRAM array periphery circuit changes allow the use of standard foundry SRAM cells and do not impact the memory access time.

The Silicon:Colloidal Quantum Dot Heterojunction.

A heterojunction between crystalline silicon and colloidal quantum dots (CQDs) is realized. A special interface modification is developed to overcome an inherent energetic band mismatch between the two semiconductors, and realize the efficient collection of infrared photocarriers generated in the CQD film. This junction is used to produce a sensitive near infrared photodetector.

Viability in delivering oral health promotion activities within the Health Promoting Schools Initiative in KwaZulu-Natal

Background. The Health Promoting Schools Initiative can provide a platform to explore integration of oral health promotion activities within the broader context of healthcare delivery. Objectives. To understand the contextualised delivery of oral health service provision within Health Promoting Schools, to conduct a situational analysis of existing services provided at these schools and to review current health and education policies. Methods. The explorative study design used a mixed methods approach. Twenty-three schools of a total sample of 154 were selected using multistage cluster sampling. Data collection comprised policy reviews, a self-administered questionnaire, a data capture sheet and an interview schedule. The study was approved by the Humanities and Social Sciences Research Ethics Committee of the University of KwaZulu-Natal (HSS/0509/013D). Results. Although policies included statements on oral health promotion, this was not translated into practice at school level. Barriers and challenges identified for successful implementation of an oral health promotion programme included lack of funds, human resources, knowledge and ownership, as well as high workloads and time constraints. Conclusion. Current delivery of oral health promotion services within the Health Promoting Schools Initiative will not reap the desired oral health outcomes owing to the inherent mismatch between policy planning and implementation. More research needs to be conducted to address opportunities and challenges facing educators and other oral healthcare providers working in the school environment.

(Invited) Vertical Tunnel FETs Using III-V Nanowire/Si Heterojunctions

A main goal of future electronic circuits is lower huge power consumption of LSIs while enhancing the chip performance. The Si-CMOS technologies are expected to change their gate-architecture, channel material, and transport mechanism to overcome the apparently-paradoxical demands which is owing to the inherent issues in miniaturization of Si MOSFETs. Enhanced short-channel effect and leakage current is emerged problem in further scaling of the transistor size. To avoid these issues, the gate structure have already changed into fin architecture [1] and will shifted to gate-all-around (GAA) [2] or surrounding-gate structure [3]. As for channel materials, III-V and Ge are promising alternative channels [4,5] because of higher carrier mobility and low electron/hole effective mass achieving higher ON-state current under lower bias. Since these materials tend to exhibit slightly high leakage current due to tunneling leakage, multi-gate architecture for these channel would necessary for decreasing leakage current. Furthermore, the inherent mobility mismatch between the III-V and Ge will be bottleneck in device-integration scheme to match current density. In near future, the III-V channel has no other choice except for vertical channel architecture to avoid the issue. In this regard, a co-integration technique of vertical III-V channel with p-channel Ge will be required for Si-CMOS. Final target is beating physical limit of conventional MOSFET especially subthreshold slope (SS) due to carrier thermal diffusion (SS = 2.3 k BT/q = 60 mV/dec). This limitation will stop further scaling of the power consumption even if a multi-gate architecture and III-V/Ge channel are applied. The steep-slope transistors such as tunnel FETs (TFETs) and impact ionization FETs [6] have therefore been proposed to overcome the limitation and to reduce supply voltage to sub-0.5 V in future LSI. These distinct features should be mutually addressed as extended CMOS technologies. In this regard, the selective-area epitaxy of III-Vs on Si will play an important role as integration technique of vertical III-V channels on Si and Ge, and the excellent III-V/Si heterojunction can assist to connect these challenges smoothly. In this paper, we review recent advances in direct integration of vertical III-V nanowire (NW)-channel on Si and FET application such as vertical III-V NW surrounding-gate transistors (SGTs) and tunneling FET (TFETs) using III-V NW/Si heterojunctions. In addition to the high-performance vertical FET application using the III-V nanowire-channel on Si, the III-V/Si heterojunction, which is formed underneath the small footprint of the III-V nanowire, is a promising junction for the use of steep-SS switches because this heterojunction shows preudo-staggered Type-II band discontinuity in the case of the n-III-V nanowire/p+ -Si heterojunctions. Under the reverse bias condition, a large Zener current depending on the carrier concentration of p-Si occurs, indicating that this current is modulated by the gate bias. Once the Fermi level is laid in the valence band in p-Si with a high carrier concentration, band-to-band tunneling appears under the forward bias. In case of a vertical steep-SS switch using the III-V nanowire/Si heterojunction, controlling the series resistance is important to achieve a steeper SS (< 60 mV/dec) because the SS is the function of VG and VDS [7]. This means a large electrical field should be induced at the heterojunction or channel region under a lower VG and VDS. In this regard, reducing the diameter of the heterojunction to avoid the trap-assisted tunneling process via defect level and forming an intrinsic layer are important for obtaining steep SS property. The device using an InAs nanowire (30 nm in diameter)/Si heterojunction demonstrated a steep SS (minimum SS = 12 mV/dec) at room temperature [7, 8]. [1]. I. Ferain et al., Nature 479 (2011) 310. [2]. J. J. Gu et al., IEEE IEDM Tech. Dig. 769 (2011). [3]. H. Takato et al., IEEE TED 38 (1991) 573. [4]. J. A. del Alamo, Nature 479 (2011) 317. [5]. H. Riel et al., MRS Bulletin 39 (2014) 668. [6]. A. M. Ionescu et al., Nature 479 (2011) 329. [7]. K. Tomioka et al., VLSI Symp. Tech. Dig. (2012) 47 [8]. K. Tomioka et al., Nano Lett. 13 (2013) 5822.

An electro-optic directed decoder based on two cascaded microring resonators

We demonstrate a directed optical decoder device consisting of two cascaded microring resonators, which are both modulated through the plasma dispersion effect. The inherent resonance wavelength mismatch between two microring resonators caused by fabrication errors is compensated for by using microheaters that are fabricated on top of the microring resonators. Two electrical signals generated by pulse pattern generators are used to modulate the PIN diodes that are embedded in the device, and the results are presented by optical signals detected at the four output ports of the device. The working wavelength and driving voltages of two MRRs are measured and analyzed by the static response spectra of the device. Dynamic experimental results show that the decoding operation is achieved at a speed of 100 Mbps.

In-situ high-resolution low energy electron diffraction study of strain relaxation in heteroepitaxy of Bi(111) on Si(001): Interplay of strain state, misfit dislocation array and lattice parameter

The relief of lattice mismatch-induced strain in Bi(111) on Si(001) heteroepitaxial system was investigated in real time as the Bi film relaxes, by means of high resolution low-energy electron diffraction (LEED). The inherent lattice mismatch of 2.5% at room temperature is accommodated through the formation of an ordered misfit dislocation array confined to the interface. The strain fields of the dislocations cause a periodic height undulation of the surface in the sub-Ångström regime, which is observed through spot splitting in LEED. From a simultaneous measurement of the position of the first-order LEED spots, which corresponds to the lattice parameter of the film, and of the separation of satellite spots, which corresponds to the ordering of the dislocation array, the evolution of the strain state during annealing of a 6nm Bi film was determined. The strain is solely relaxed by full edge-type dislocations arranged in the ordered array at the interface. From the remaining strain of ε=0.6% the critical thickness for generation of misfit dislocations under equilibrium conditions can be derived.

Innovation in the Standard of Globalization Sukuk

The purpose of this paper is examination the several of Current Islamic Sukuk models and approaches in Islamic finance. In the aftermath of the financial crisis of 2007–2008, the fundamental stability of the conventional financial system has been seriously questioned. Excessive leveraging, combined with an inherent asset-liability mismatch, exposes institutions to unsupportable risk, and threatens the overall soundness of the financial system. An alternative to the current model is one traditionally advocated by Islam. Islamic finance eliminates debt financing and instead promotes equity or direct asset financing, which allows for risk-sharing instead of risk-shifting. Financial institutions serve their traditional role as intermediaries between savers and investors, but with no debt on their balance sheets, eliminating the potential for excessive risk. The stability of the international financial system would be enhanced if reliance on debt were reduced: the global financial system would rely more heavily on risk-sharing, equity finance, and genuine asset securitization, linking the payoffs of financial securities to the underlying assets that are financed.

Frequency-Agile Multiband Quadrature Sigma-Delta Modulator for Cognitive Radio: Analysis, Design and Digital Post-Processing

A quadrature ΣΔ analog-to-digital converter (ADC) is a promising solution for intermediate frequency digitizing software defined cognitive radio (CR) receivers because of, e.g., multiband capability and power efficiency. However, inherent coefficient mismatches between the in-phase and quadrature rails can severely damage the performance of such receiver by creating mirror-frequency interference (MFI). In this article, a novel frequency-agile and reconfigurable transfer function design, allowing digital post-compensation of the MFI, is proposed. The design is based on a novel closed-form transfer function model for higher-order quadrature ΣΔ modulators (QΣΔMs) under implementation inaccuracies, proposed herein. By doing the compensation in digital domain, it is possible to take into account all error-sources of the receiver chain at once, including, e.g., a quadrature mixer before the ADC. This capability is obtained by preserving the mirror-band signal information and using the noise transfer function of a QΣΔM to remove quantization noise from therein. This is demonstrated in a multiband scenario aimed for CR receivers, where a number of frequency channels can be received and detected in parallel. Practical examples of the transfer function analysis under implementation inaccuracies and the post-compensation performance are given with a two-stage QΣΔM, having stage-orders of four, allowing eighth-order noise shaping.

Self-Assembled DNA Nanopores That Span Lipid Bilayers

DNA nanotechnology excels at rationally designing bottom-up structures that can functionally replicate naturally occurring proteins. Here we describe the design and generation of a stable DNA-based nanopore that structurally mimics the amphiphilic nature of protein pores and inserts into bilayers to support a steady transmembrane flow of ions. The pore carries an outer hydrophobic belt comprised of small chemical alkyl groups which mask the negatively charged oligonucleotide backbone. This modification overcomes the otherwise inherent energetic mismatch to the hydrophobic environment of the membrane. By merging the fields of nanopores and DNA nanotechnology, we expect that the small membrane-spanning DNA pore will help open up the design of entirely new molecular devices for a broad range of applications including sensing, electric circuits, catalysis, and research into nanofluidics and controlled transmembrane transport.