Improvement In Figure Of Merit Research Articles

Investigations of 4H‐SiC trench MOSFET with integrated high‐K deep trench and gate dielectric

AbstractThis paper proposes and investigates a novel 4H‐SiC trench MOSFET (TMOS) with integrated high‐K deep trench and gate dielectric (INHK‐TMOS). The integrated high‐K (INHK) consists of a high‐K gate dielectric and an extended high‐K deep trench dielectric in the drift region. Firstly, the high‐K gate dielectric together with the metal‐forming high‐K metal gate structure, which increases the gate oxide capacitance (COX), reduces the threshold voltage (VTH) and the specific on‐resistance (Ron,sp). Secondly, the extended high‐K deep trench dielectric not only modulates the electric field in the drift region by introducing a new electric field peak at the bottom of the high‐K deep trench dielectric, thereby enhancing the breakdown voltage (BV), but also improves the doping concentration (ND) of the drift region by the assist depletion effect of the high‐K dielectric, further optimizing the forward conduction characteristics. Simulation results demonstrate that when compared to the conventional TMOS, the INHK‐TMOS using HfO2 exhibits a 52.6% reduction in VTH, a 52.1% reduction in Ron,sp, a 20.3% increasement in BV and a 202.3% improvement in figure of merit.

Raman effect and unusual transport properties of Co-doped Mn2FeAl Heusler alloy

Semiconducting materials with a distinctive blend of high electrical and low thermal conductivity are required for efficient thermoelectric devices. In this aspect, Heusler alloys are potential candidates for thermoelectric materials. It has been observed that Co doping in Mn2FeAl enhances the electrical conductivity as well as reduces the thermal conductivity of the system leading to an improvement in figure of merit. The Seebeck coefficient suggested the p-type behavior over the whole temperature range, followed by a maximum at 150 K. Additionally, the electronic properties of the suggest that the observed Raman mode is due to the electronic excitations in the system. Interestingly, this system shows a decoupling between the Seebeck coefficient and electrical conductivity, suggesting the promising potential of as a thermoelectric material and offering valuable insights into its electronic properties.

Performance analysis of heterostructure-based topological nanophotonic sensor

In this manuscript, a heterostructure-based topological nanophotonic structure is proposed for improved sensing performance. The topological effect is realized by connecting two dissimilar one-dimensional photonic crystal structures having overlapped photonic bandgaps. The structural parameters are optimized to regulate and alter the dispersion characteristics, which results in the opposite Zak phases. This demonstrates a robust topologsical interface state excitation at a 1737 nm operating wavelength. Further, a topological cavity structure having resonance mode at 1659 nm is formed by replacing the interface layers with a defect layer. The mode excitation is confirmed by analyzing the electric field confinement at the interface. The sensing capability of the structure is analytically evaluated by infiltrating different analytes within the cavity. The analytical results demonstrate the device’s average sensitivity of around 774 nm/Refractive index unit (RIU) along with an average high Q-factor and figure of merit of around 5.2 × 104 and 2.6234 × 104 RIU−1, respectively. Because of the higher interface mode field confinement, the proposed structure exhibits a 92% higher sensitivity, 98% improved Quality factor, 206% improvement in figure of merit, and 86% higher interface field confinement than conventional Fabry–Perot resonator structures. Thus, the proposed topological cavity structure shows its broad sensing ability (Refractive Index: 1.3–1.6) along with a low-cost, simple fabrication and characterization process, promoting the development of highly sensitive planner nanophotonic devices.

Application of Leading-Edge Tubercles on Rotor Blades

This study explores the effects of leading-edge tubercles applied to a canonical rotor blade in an effort to improve aerodynamic performance of a rotor in hover, without sacrificing forward flight performance. Various tubercle shapes and configurations were analyzed using computational fluid dynamic simulations using Euler and Reynolds-averaged Navier–Stoke equations. Improvements in figure of merit up to 3% were found over the baseline rotor for specific tubercle configurations when operating at pitch angles between 2 and 11 deg and tip Mach numbers between 0.6 and 0.83. An increase in thrust coefficients and reduction in power coefficients over the baseline rotor were both attributed to alteration of flow behavior in different regions of the rotor blade when leading-edge tubercles were applied.

Hybrid Monte Carlo methods for Geant4-based nuclear well logging implementation

Monte Carlo method is one of most common numerical methods used in nuclear well logging simulations, but it can be very time-consuming when faced with deep penetration problems.In practice, hybrid Monte Carlo or partially deterministic methods are widely used to improve the conventional Monte Carlo computation efficiency. This work aims to apply one of the state-of-the-art hybrid methods, CADIS and FW-CADIS, to enhance the performance of current nuclear well logging simulation process. This is achieved by implementing CADIS and FW-CADIS method into a framework based on the open-source Monte Carlo code Geant4. Two representative nuclear logging tools designed for field production are selected to verify the performance of the hybrid Monte Carlo Geant4 framework. We evaluate the enhancement by calculating the Figure of Merit (FOM) from the variance of total detector flux. The results show that the simulation efficiency can be improved by using CADIS and FW-CADIS method. The maximum improvement of FOM is 1444 times in the gamma density tool and 159 times in the neutron porosity tool.

Comparison of metal oxide and composite phase change material based nanofluids as coolants in mini channel heat sink

Present work focuses on heat transfer and pressure drop studies of Al2O3 based nanofluids and nanoencapsulated composite phase change material (NECPCM) based nanofluids in mini channel heat sink. Composite PCM was prepared by homogeneously mixing paraffin wax and petroleum jelly. The encapsulation of composite PCM in polystyrene shells was done by mini emulsion polymerization and various characterizations were done to study phase change behaviour. The concentration of NECPCM and Al2O3 nanofluids was fixed based on zeta potential measurements. Experiments were conducted in mini channel integrated with a heat sink, consisting of 13 rectangular channels and hydraulic diameter of 2.6 mm. Maximum heat transfer enhancement of 28% was obtained for NECPCM nanofluid against 10% enhancement for Al2O3 nanofluid. Higher pressure drop was observed for Al2O3 nanofluid as compared to NECPCM nanofluids, especially at higher flow rates. Maximum improvement in figure of merit (FOM) obtained for NECPCM nanofluid and Al2O3 nanofluid was 24% and 5% respectively, as compared to DI water. The experimental results show that there exists an optimum flow rate for NECPCM based nanofluids to achieve maximum FOM, which depends on length of the channel and residence time of particles.

Figure of merit enhancement of Ti3C2Tx-graphene based long-range surface plasmon sensor at telecommunication wavelength

In this work, the long-range surface plasmon resonance (LRSPR) sensor based on dielectric Ti3C2Tx-graphene layers is demonstrated. Here, MXene (Ti3C2Tx) is used as a metal for strong surface plasmon’s generation at 1550 nm excitation wavelength. Graphene is used to attach the biomolecules having carbon–carbon structure with pi stacking interactions. The detection accuracy (DA) and figure of merit (FoM) for the proposed LRSPR sensor is theoretically investigated at telecommunication wavelength. The highest FoM of (559.64 RIU−1) is obtained at 3100 nm dielectric thickness and 14 nm Ti3C2Tx thickness of the proposed sensor. The maximum improvement in FoM is 273% to the traditional LRSPR sensors. Propagation depths are also evaluated for Au-graphene and proposed LRSPR sensor at 14 and 27 nm thicknesses of Ti3C2Tx We believe that the Ti3C2Tx can be used in place of metals for strong plasmon generation in future sensor designs at telecommunication wavelengths.

Experimental investigation of tip anhedral effects on the aerodynamics of a model helicopter rotor in hover

This study experimentally investigates the effects of tip anhedral on the rotor aerodynamic performance and the tip vortex characteristics in hovering flight. A five-bladed scaled helicopter rotor with blades that have either rectangular (baseline) or anhedral tip geometries was used as the experimental model. Thrust and torque measurements were performed at the tip Mach numbers (Mtip) of 0.3 and 0.4 at five different pitch angles. In addition, flow field measurements via phase-locked particle image velocimetry technique were conducted at Mtip = 0.4 for a selected pitch angle. Thrust and torque measurements reveal that the anhedral tip configuration reaches a maximum Figure of Merit (FOM) value of 0.67 yielding approximately 5% FOM improvement when compared to the rectangular blade at Mtip = 0.3. It is observed that the tip anhedral changes the tip vortex trajectory by increasing the radial contraction of the wake and decreasing the average axial convection speed in the range of the wake age considered in this study. The meandering amplitude of the tip vortex increases abruptly after the passage of the proceeding blade in both cases yet a greater increase is observed in the anhedral tip configuration. Moreover, the axial convection of the previously shed tip vortices in the downstream direction is significantly slowed down during the course of the blade passage such that they reside close to the rotor disc in the anhedral case. The resultant proximity of the tip vortices to the blade with anhedral tip configuration promotes the induced flow in the radially inwards direction, which probably attenuates the strength of the newly forming tip vortex. Accordingly, the maximum tangential velocity and circulation of the tip vortex are reduced by 20% and 13%, respectively, when compared to the rectangular blade case. The reduced tip-vortex circulation is consistent with the increased FOM value. A good agreement was found with the Vatistas vortex model using n=3 for the rectangular blade and n=2.2 for the blade with tip anhedral.

Significant Reduction in Thermal Conductivity and Improved Thermopower of Electron‐Doped Ba1–xLaxTiO3 with Nanostructured Rectangular Pores

AbstractElectron‐doped BaTiO3 is a less studied n‐type metal oxide thermoelectric material. In this work, the electrical conductivity of BaTiO3 samples has been improved by introducing La to yield an n‐type Ba1–xLaxTiO3 semiconducting material. Density functional theory calculations show that the optimal electron‐doping occurs at x = 0.2, and this is also confirmed experimentally. To improve the thermoelectric properties further, nanostructured cuboidal pores are introduced into the bulk Ba1–xLaxTiO3 using F127 surfactant micelles for a chemical templating process, followed by spark plasma sintering. Interestingly, transmission electron microscopy images and X‐ray powder diffraction analysis confirms that our fabricated samples are cubic BaTiO3 perovskite phase with the nanostructured rectangular‐prism pores of >4 nm. Scanning electron microscopy images show that all the samples have similar grain boundaries and uniform La doping, which suggests that the large reduction in the lattice thermal conductivity in the F127‐treated samples arises primarily from the pore distribution, which introduces anisotropic phonon scattering within the unique nanoarchitecture. The sample with 20 at% La doping and nanopores also shows a thermopower that is doubled compared to the related sample without porosity. Together with the lattice thermal conductivity, enables a significant improvement in figure of merit, zT compared to the other samples.

Fermi level tuning in modified Bi2Te3 system for thermoelectric applications.

The techniques of size reduction and defect engineering have attracted great interest as an effective strategy for developing new and modified thermoelectric materials with high performance. Here, we investigated the thermoelectric properties of the Bi2Te3 system modified by Fermi level tuning through the methods of nanostructuring and doping. Band structure modification and Fermi level shift contribute to the better thermoelectric performance of the material. A minimum thermal conductivity of 0.72 W K−1 was obtained at 440 K with a reduction of 50% as compared to the pristine sample. The improved transport properties along with considerably reduced thermal conductivity result in a two-fold improved figure of merit of 0.295 at 420 K for the nanostructured sample Bi0.4Sb1.6Te3 over pristine Bi2Te3.

Graphitic carbon nitride-bismuth antimony telluride nanocomposites: A potential material for thermoelectric applications

Modified forms of Bi2Te3 system attracts immense importance in thermoelectric generation by providing a green and clean technology for converting low-grade waste heat into electrical energy. Herein, we have explored the potential of a new material graphitic carbon nitride (g-C3N4) for tuning the thermoelectric properties of Bi0·4Sb1·6Te3. The electronic and lattice transport properties of Bi0·4Sb1·6Te3 are effectively decoupled through nanostructuring, modification of carrier concentration through defect engineering and embedding g-C3N4 nanostructures in the bulk material which leads to the synergetic optimization of power factor and suppressed thermal conductivity due to all-scale hierarchical architecture. All the Bi0·4Sb1·6Te3/g-C3N4 nanocomposites exhibit reduction in thermal conductivity and we obtained an ultra-low thermal conductivity of 0.33 W/mK for Bi0·4Sb1·6Te3 nanocomposite with 1% g-C3N4. The simultaneous optimization of electrical and lattice transport properties leads to a marked improvement in figure of merit from 0.295 for pristine Bi0·4Sb1·6Te3 to a peak value of 1.09 for Bi0·4Sb1·6Te3 with 0.50% g-C3N4.

Fluorescence-kinetic four-way data generation and modeling for abacavir determination in water samples

The aim of this study was to develop a fluorescence-detection based analytical methodology consisting in the photolysis of abacavir induced by UV irradiation to determine the concentration of the analyte in complex samples. Initially, with the goal of maximizing the fluorescence signal, the optimal experimental conditions were determined by means of design of experiments using the response surface methodology. Once these conditions were established, two types of data were generated: excitation-emission fluorescence matrices acquired after UV irradiation of the analyte (second-order data), and excitation-emission fluorescence matrices recorded at different irradiation times (third-order data), which were processed using both multivariate curve resolution by alternating least squares (MCR-ALS) and parallel factor analysis (PARAFAC) algorithms. These strategies were carried out with the objective of assessing the chemometric advantages in terms of predictive ability by increasing the order of the data, and improvement in figures of merit, such as sensitivity and limits of detection and quantitation. Finally, test samples, containing the analyte and potential interferences, and water samples were evaluated. This study allowed the development of a simple and sensitive methodology for the determination of abacavir in water samples, and showed similar predictive ability between both algorithms. The analytical figures of merit displayed limits of detection and quantitation of 3–5 µg L−1 and 11–14 µg L−1, respectively. The main advantages of third-order data with respect to second-order data were associated with improvements in selectivity and precision.

High-${Q}$ Variable Pitch Spiral Inductors for Increased Inductance Density and Figure-of-Merit

Layout-optimized inductors with gradually varying width and spaced (tapered) spirals are well known for their higher quality factor ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${Q}$ </tex-math></inline-formula> ) characteristics. For the first time, the significance of tapered inductors in achieving higher inductance ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${L}$ </tex-math></inline-formula> ) density is brought out in this article. Instead of having a constant spiral pitch (width + space), gradually reducing pitch with increased turns is shown to significantly benefit <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${L}$ </tex-math></inline-formula> density without compromising on <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${Q}$ </tex-math></inline-formula> . Following this approach, inductor figure-of-merit (FOM) is shown to increase with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${L}$ </tex-math></inline-formula> density using variable pitch spirals while it is reduced in other spiral configurations. It is also revealed that for fixed inner and outer diameters, significant FOM improvement can be achieved only through increased <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${L}$ </tex-math></inline-formula> density and not through higher <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${Q}$ </tex-math></inline-formula> . Moreover, the proposed approach is shown to have improved inductor FOM across substrate resistivities and metal thickness values. Prototype-tapered inductors (shown in <xref ref-type="fig" rid="fig1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Fig. 1</xref> ) designed using the proposed approach are fabricated using 0.35- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> BiCMOS technology. Measurements (which are in good agreement with electromagnetic (EM) simulations) show higher <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${L}$ </tex-math></inline-formula> values of 6.6 nH with a high- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${Q}$ </tex-math></inline-formula> of 23 usable at 3.8 GHz, thereby achieving a very high FOM of 4.3. <fig id="fig1" orientation="portrait" position="float" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><label>Fig. 1.</label><caption> Chip images of prototype variable width and constant spacing inductors. (a) D1. (b) D2. </caption> <graphic orientation="portrait" position="float" xlink:href="sunda1ab-2937671.eps"/> </fig>

Workfunction engineered stepped gate SJ UMOS with reduced specific resistance for high speed applications

In this paper, trench superjunction MOS (SJ UMOS) utilizing workfunction engineered stepped gate for performance enhancement is proposed. N+ polysilicon (Φm = 4.17 eV) layer in between two P+ polysilicon (Φm = 5.25 eV) layer connected by a metal gate is incorporated in the proposed device. Additionally, gate oxide thickness is increased in steps from source to drain resulting in enhanced gate-source capacitance and reduced gate-drain capacitance. The electrical behavior of conventional and proposed device is investigated using 2D numerical simulations. The results indicate 19.5% reduction in specific resistance without degrading the breakdown voltage. Further, the proposed structure also exhibits 28.9% reduction in specific gate to drain charge, 30.5% increment in gate to source charge and 54% reduction in switching delay. In addition to this, Baliga’s figure of merit (BFOM) along with other technology figure of merit (FOM) has also been evaluated, demonstrating a 26% increment in BFOM. The significant improvement in FOM is attributed to reduced specific resistance and gate to drain charge of the proposed structure. Additionally, the impact of temperature on device performance is also evaluated and no degradation in the device parameters is observed.

Sensing self-referenced fiber optic long-range surface plasmon resonance sensor based on electronic coupling between surface plasmon polaritons.

A type of hollow gold nanoparticle (HGNP)-modified fiber optic long-range surface plasmon resonance (LRSPR) sensor with sensing self-reference is proposed and demonstrated. HGNPs have a stronger plasmonic field compared to solid GNPs because of the coupling between the inner and outer walls of HGNPs. The intense near-field electronic coupling between long-range surface plasmon polaritons associated with the LRSPR gold layer and localized surface plasmon polaritons of HGNPs leads to localized electromagnetic-field enhancement and LRSPR response signal amplification. Therefore, the HGNP-modified LRSPR sensor possesses a more excellent sensing property compared with the unmodified LRSPR sensor. The long-range resonance dip in the transmission spectrum is shown to shift in response to ambient refractivity change, and the characteristic absorption peak is fixed, allowing to regard it as a reference to improve detection accuracy of the sensors. The mode-field distribution of the sensors is simulated by using the finite element method, and the simulation results show that the electric-field intensity on the HGNP surface is significantly enhanced compared with that of the gold layer surface of the unmodified LRSPR sensor. 1874.79 nm/RIU improvement in sensitivity, 1.42 times improvement in figure of merit (FOM), and approximately 50% reduction in limit of detection (LOD) are achieved for the refractivity measurement of a low-concentration biological solution with the employment of HGNPs in LRSPR sensing experiments. The HGNP-modified LRSPR sensor proposed in this paper has high detection accuracy and FOM and low LOD, and can realize remote real-time online monitoring. Therefore, it has important research value and broad application prospects in the field of biochemical detection.

A 1-mW Class-AB Amplifier With −101 dB THD+N for High-Fidelity 16 $\Omega$ Headphones in 65-nm CMOS

A low-power class-AB amplifier for high-fidelity headphones is presented. The linearity of a class-AB amplifier strongly depends on the loop gain over the audio band and voltage swing. In this paper, a cascode-driven mesh technique limits the number of high-swing nodes in the output stage, thereby preserving the loop gain of the preceding gain stages. A frequency compensation scheme is proposed that extends the unity-gain bandwidth (UGB) and increases the loop gain at 20 kHz. Combining these two techniques, the amplifier achieves −101.4-dB total harmonic distortion plus noise (THD+N) over the full audio band, the lowest ever reported nonlinearity among sub-milliwatt CMOS class-AB amplifiers. The amplifier delivers 51.2-mW peak power to a $16\Omega \|0.33$ -nF load while consuming 0.97 mW of total static power. It has UGB of 12.3 MHz and SNR of 108 dB. These results are consistent when measured over eight test chips. Compared to the recent prior art, the amplifier exhibits >12 dB better linearity and >14-dB dynamic range. This results in 2.5 $\times $ improvement in figure of merit (FOM = Peak Load Power/(Quiescent Power $\times $ THD+N[%])). It occupies 0.16 mm 2 in a standard 65-nm CMOS.

Voltage-Controlled Ring Oscillator With FOM Improvement by Inductive Loading

A hybrid voltage-controlled oscillator (VCO) architecture based on a ring oscillator with inductive loading is proposed. It exhibits a better phase noise/power figure-of-merit (FOM) than a standard ring VCO while retaining some of its desirable properties. It can be used as a “drop-in” replacement in a ring-VCO-based phase-locked loop to obtain a predictable improvement in FOM. Accurate and concise expressions are provided for predicting the frequency and the FOM improvement. A prototype exhibited 8 dB of FOM improvement with respect to a standard ring VCO, while the error on the theoretical prediction was less than 1 dB when compared to measured data.

Area Efficient Shared Diode Multi-Level Cell SOT-MRAM

This paper proposes a diode-based multi-level cell spin–orbit torque magnetic random-access memory (SOT-MRAM) for high density memory applications. By stacking a shared diode over two in-parallel magnetic tunnel junctions (MTJs) that share a common heavy metal electrode, our proposed cell requires only one silicon-based transistor to access 2 bits. Having just one transistor to access 2 bits results in at least $2\times $ higher density when compared to various designs in the literature. Moreover, utilizing a high-density MRAM process, a $4F^{2}$ effective 1 bit area can be achieved. Furthermore, our proposed design maintains the high energy efficiency of the conventional SOT-MRAM. In addition, an improvement in figure of merit of at least 30% defined as energy area product is obtained compared to various designs. This paper also discusses the essential requirements to realize our proposed SOT-MRAM, such as the realization of diode MTJ stack and SOT-MTJs, with different critical currents and electrical resistances.

Development and Validation of Deep Learning-based Automatic Detection Algorithm for Malignant Pulmonary Nodules on Chest Radiographs.

Purpose To develop and validate a deep learning-based automatic detection algorithm (DLAD) for malignant pulmonary nodules on chest radiographs and to compare its performance with physicians including thoracic radiologists. Materials and Methods For this retrospective study, DLAD was developed by using 43 292 chest radiographs (normal radiograph-to-nodule radiograph ratio, 34 067:9225) in 34 676 patients (healthy-to-nodule ratio, 30 784:3892; 19 230 men [mean age, 52.8 years; age range, 18-99 years]; 15 446 women [mean age, 52.3 years; age range, 18-98 years]) obtained between 2010 and 2015, which were labeled and partially annotated by 13 board-certified radiologists, in a convolutional neural network. Radiograph classification and nodule detection performances of DLAD were validated by using one internal and four external data sets from three South Korean hospitals and one U.S. hospital. For internal and external validation, radiograph classification and nodule detection performances of DLAD were evaluated by using the area under the receiver operating characteristic curve (AUROC) and jackknife alternative free-response receiver-operating characteristic (JAFROC) figure of merit (FOM), respectively. An observer performance test involving 18 physicians, including nine board-certified radiologists, was conducted by using one of the four external validation data sets. Performances of DLAD, physicians, and physicians assisted with DLAD were evaluated and compared. Results According to one internal and four external validation data sets, radiograph classification and nodule detection performances of DLAD were a range of 0.92-0.99 (AUROC) and 0.831-0.924 (JAFROC FOM), respectively. DLAD showed a higher AUROC and JAFROC FOM at the observer performance test than 17 of 18 and 15 of 18 physicians, respectively (P < .05), and all physicians showed improved nodule detection performances with DLAD (mean JAFROC FOM improvement, 0.043; range, 0.006-0.190; P < .05). Conclusion This deep learning-based automatic detection algorithm outperformed physicians in radiograph classification and nodule detection performance for malignant pulmonary nodules on chest radiographs, and it enhanced physicians' performances when used as a second reader. © RSNA, 2018 Online supplemental material is available for this article.

Performance comparison of land change modeling techniques for land use projection of arid watersheds

The change of land use/land cover has been known as an imperative force in environmental alteration, especially in arid and semi-arid areas. This research was mainly aimed to assess the validity of two major types of land change modeling techniques via a three dimensional approach in Birjand urban watershed located in an arid climatic region of Iran. Thus, a Markovian approach based on two suitability and transition potential mappers, i.e. fuzzy analytic hierarchy process and artificial neural network-multi layer perceptron was used to simulate land use map. Validation metrics, quantity disagreement, allocation disagreement and figure of merit in a three-dimensional space were used to perform model validation. Utilizing the fuzzy-analytic hierarchy processsimulation of total landscape in the target point 2015, quantity error, the figure of merit and allocation error were 2%, 18.5% and 8%, respectively. However, Artificial neural network-multi layer perceptron simulation led to a marginal improvement in figure of merit, i.e. 3.25%.