Offset Calculations Research Articles

An Integrated Gather-and-Distribute Mechanism and Attention-Enhanced Deformable Convolution Model for Pig Behavior Recognition.

The behavior of pigs is intricately tied to their health status, highlighting the critical importance of accurately recognizing pig behavior, particularly abnormal behavior, for effective health monitoring and management. This study addresses the challenge of accommodating frequent non-rigid deformations in pig behavior using deformable convolutional networks (DCN) to extract more comprehensive features by incorporating offsets during training. To overcome the inherent limitations of traditional DCN offset weight calculations, the study introduces the multi-path coordinate attention (MPCA) mechanism to enhance the optimization of the DCN offset weight calculation within the designed DCN-MPCA module, further integrated into the cross-scale cross-feature (C2f) module of the backbone network. This optimized C2f-DM module significantly enhances feature extraction capabilities. Additionally, a gather-and-distribute (GD) mechanism is employed in the neck to improve non-adjacent layer feature fusion in the YOLOv8 network. Consequently, the novel DM-GD-YOLO model proposed in this study is evaluated on a self-built dataset comprising 11,999 images obtained from an online monitoring platform focusing on pigs aged between 70 and 150 days. The results show that DM-GD-YOLO can simultaneously recognize four common behaviors and three abnormal behaviors, achieving a precision of 88.2%, recall of 92.2%, and mean average precision (mAP) of 95.3% with 6.0MB Parameters and 10.0G FLOPs. Overall, the model outperforms popular models such as Faster R-CNN, EfficientDet, YOLOv7, and YOLOv8 in monitoring pens with about 30 pigs, providing technical support for the intelligent management and welfare-focused breeding of pigs while advancing the transformation and modernization of the pig industry.

Slab surface passivation and its application to band offset calculations for polar heterointerfaces of zinc-blende semiconductors

Slab surface passivation and its application to band offset calculations for polar heterointerfaces of zinc-blende semiconductors

Characterisation of Methane Production Pathways in Sediment of Overwashed Mangrove Forests

Methane (CH4) emissions in mangrove ecosystems may complicate the ecosystem’s potential carbon offset for climate change mitigation. Microbial processes and the mass balance of CH4 in mangrove sediment are responsible for the emissions from the ecosystems. This is the follow up of our previous research which found the super saturation of CH4 in the pore water of mangrove sediment compared to atmospheric CH4 and the lack of a correlation between pore water sulphate and CH4 concentrations. This study is going to investigate methane production pathways in the sediment of overwashed mangrove forests. Two approaches were used to study methanogens here: (1) the spread plate count method and the quantitative polymerase chain reaction (qPCR) method, and (2) laboratory experiments with additional methanogenic substrates (methanol, acetate, and hydrogen) to determine which substrates are more conducive to methane production. According to the qPCR method, methanogen abundance ranged from 72 to 6 × 105 CFU g−1 sediment, while SRB abundance ranged from 2 × 102 to 2 × 105 CFU g−1 sediment. According to the plate count method, the abundance of methylotrophic methanogens (the only group of methanogens capable of competing with SRBs) ranged from 8.3 × 102 to 5.1 × 104 CFU g−1, which is higher than the abundance of the other group of methanogens (0 to 7.7 × 102 CFU g−1). The addition of methanol to the sediment slurry, a substrate for methylotropic methanogens, resulted in a massive production of CH4 (up to 9 × 104 ppm) and intriguingly the control treatments with autoclaving did not kill methanogens. These findings suggested that mangrove ecosystems in the marine environment provide favourable conditions for methanogens and further characterisation of the methanogen involved in the process is required. As a result, future research in this ecosystem should include methane production in carbon offset calculations, particularly due to methylotropic methanogenesis.

STEM courses are harder: evaluating inter-course grading disparities with a calibrated GPA model

BackgroundGrades in college and university STEM courses are an important determinant of student persistence in STEM fields. Recent studies have used the grade offset/grade penalty method to explore why students have lower grades in STEM courses than their GPAs would predict. The results of these studies are in doubt; however, as they use GPA as a reliable measure of academic performance, which is a disputed assumption. Using a predictive model of student performance, it is possible to produce a more accurate measure of academic performance than the observed GPA and discover if STEM courses are graded more stringently, and under which circumstances.ResultsA weighted logistic model of GPA better predicts academic performance than the observed GPA. Using this calibrated GPA it is found that the grade offset method predicts that STEM courses, departments, and programs grade significantly more stringently than non-STEM courses. The average grade difference between STEM and non-STEM course grades and GPAs is around four tenths of a grade point. An exception is general education courses offered by STEM departments, which are graded with the same leniency as non-STEM courses. Grade offset calculations that use the observed GPA systematically underestimate the negative offset in STEM grading relative to calculations that use the calibrated GPA. The calibrated GPA is much more highly correlated with standardized tests such as the ACT (r = 0.49) than the observed GPA is (r = 0.25).ConclusionObserved GPA is a systematically biased measure of academic performance, and should not be used as a basis for determining the presence of grading inequity. Logistic models of GPA provide a more reliable measure of academic performance. When comparing otherwise academically similar students, we find that STEM students have substantially lower grades and GPAs, and that this is the consequence of harder (more stringent) grading in STEM courses.

A density functional theory study on the interface stability between CsPbBr3 and CuI

This paper assesses the interface stability of the perovskite CsPbBr3 and transport layer CuI using density functional theory and band offset calculations. As a low-cost, more stable alternative to current hole transport materials, CuI may be used to template the epitaxial growth of perovskites such as CsPbBr3 owing to a 1% lattice constant mismatch and larger bulk modulus. We compare all eight atomic terminations of the interfaces between the (100) low-energy facet for both CsPbBr3 and CuI, increasing material thickness to consider charge density redistribution and bonding characteristics between surface and bulk-like regions. A low energy atomic termination is found to exist between these materials where alternating charge accumulation and depletion regions stabilize bonds at the interface. Band offset calculations reveal a type I straddling gap offset in the bulk shifting to a type II staggered gap offset as the thickness of the materials is increased, where the built-in potential changes as layer thickness increases, indicating the tunability of charge separation at the interface. CuI may, thus, be used as an alternative hole transport layer material in CsPbBr3 optoelectronic devices.

Hybrid band offset calculation for heterojunction interfaces between disparate semiconductors

Accurate band offset calculations are challenging for heterojunction interfaces that consist of two very different host materials. For this, the key requirement is to have the correct bandgap of each material at the same time. A hybrid calculation scheme (HSE/-U scheme) is proposed to model the band offsets of such interfaces. Our HSE/-U method applies the hybrid functional for the whole interface supercell, but with an additional “reverse GGA+U” on the narrow gap semiconductor side, guaranteeing the correct bandgaps on both sides. Several supercell calculations of dielectric films including HfO2, ZrO2, Al2O3, TiO2, and GaN on an insulating phase VO2 are tested to verify it. All the studied oxides show the type-I band alignment with VO2, and the band edge line-up agrees well with the available experimental reports, supporting the reliability of the proposed hybrid calculation scheme.

Instability of insular tree communities in an Amazonian mega‐dam is driven by impaired recruitment and altered species composition

Abstract Mega‐dams create highly fragmented archipelagos, affecting biodiversity and ecosystem functioning in remnant forest isolates. This study assessed the long‐term impact of dam‐induced fragmentation on insular tropical tree communities, with the aim of generating robust recommendations to mitigate some of the detrimental biodiversity impacts associated with future dam development. We inventoried adult and sapling trees across 89 permanent plots, located on 36 islands and in three mainland continuous forest sites in the Balbina Dam, Brazilian Amazon. We examined differences in recruitment, structure, and composition of sapling and adult tree communities, in relation to plot‐, patch‐ and landscape‐scale attributes including area, isolation, and fire severity. Islands harboured significantly lower sapling (mean ± 95% CI 48.6 ± 3.8) and adult (5 ± 0.2) tree densities per 0.01 ha, than nearby mainland continuous forest (saplings, 65.7 ± 7.5; adults, 5.6 ± 0.3). Insular sapling and adult tree communities were more dissimilar than in mainland sites, and species compositions showed a directional shift away from mainland forests, induced by fire severity, island area, and isolation. Insular sapling recruitment declined with increasing fire severity; tree communities with higher community‐weighted mean wood density showed the greatest recruitment declines. Our results suggest that insular tree communities are unstable, with rare species becoming extinction‐prone due to reduced tree recruitment and density on islands, potentially leading to future losses in biodiversity and ecosystem functioning across Balbina's >3,500 reservoir islands. Policy implications. In Balbina, fire and reduced habitat area and connectivity were drivers of tree community decay after only 28 years of insularization, despite strict protection provided by the ~940,000 ha Uatumã Biological Reserve. Given that many dams are planned for lowland, moderately undulating Amazonia, we recommend that dam development strategy explicitly considers (a) dam location, aiming to minimize creation of small (<10 ha) and isolated islands, (b) maintaining reservoir water levels during droughts to reduce fire risk, and (c) including aggregate island area in environmental impact and offset calculations. Ideally, we recommend that alternatives to hydropower be sought in lowland tropical regions, due to the far‐reaching biodiversity losses and ecosystem disruption caused by river impoundment.

Shoelaces: an interactive tool for ribosome profiling processing and visualization

BackgroundThe emergence of ribosome profiling to map actively translating ribosomes has laid the foundation for a diverse range of studies on translational regulation. The data obtained with different variations of this assay is typically manually processed, which has created a need for tools that would streamline and standardize processing steps.ResultsWe present Shoelaces, a toolkit for ribosome profiling experiments automating read selection and filtering to obtain genuine translating footprints. Based on periodicity, favoring enrichment over the coding regions, it determines the read lengths corresponding to bona fide ribosome protected fragments. The specific codon under translation (P-site) is determined by automatic offset calculations resulting in sub-codon resolution. Shoelaces provides both a user-friendly graphical interface for interactive visualisation in a genome browser-like fashion and a command line interface for integration into automated pipelines. We process 79 libraries and show that studies typically discard excessive amounts of quality data in their manual analysis pipelines.ConclusionsShoelaces streamlines ribosome profiling analysis offering automation of the processing, a range of interactive visualization features and export of the data into standard formats. Shoelaces stores all processing steps performed in an XML file that can be used by other groups to exactly reproduce the processing of a given study. We therefore anticipate that Shoelaces can aid researchers by automating what is typically performed manually and contribute to the overall reproducibility of studies. The tool is freely distributed as a Python package, with additional instructions, tutorial and demo datasets available at https://bitbucket.org/valenlab/shoelaces.

Methods and codes for reservoir–atmosphere 14C age offset calculations

Reservoir 14C age offsets are invaluable tracers for past changes in carbon cycle and oceanic circulation. Reconstruction of reservoir age offsets with time is also required for calibration purposes (reconstruction of atmospheric calibration curve, calibration of non-atmospheric radiocarbon ages). Thus, properly propagating the various uncertainties linked to reservoir age offset is important for proper interpretation. However, approaches for reservoir age offset calculation – especially when considering pairs of reservoir-derived 14C and calendar ages – are usually not detailed and inadequate for proper propagation of uncertainties. Here, the various ways to properly calculate reservoir age offsets are described with a focus on a new approach when considering pairs of 14C and calendar ages. This approach maps the calendar age distribution onto the 14C time scale prior to reservoir age offset calculation – the “uncalibration-convolution process”. R codes computing reservoir age offsets based on available data are presented. Finally, a case study focusing on the reconstruction of the speleothem-atmosphere 14C age offsets of speleothem 14C data used in the latest release of the atmospheric calibration curve is discussed.

P209 Standardisation Of Lung Clearance Index In A Multicentre Clinical Trial

Introduction Lung clearance index (LCI) is a sensitive and repeatable non-invasive measure of ventilation inhomogeneity derived from the multiple breath washout (MBW) technique. It is more sensitive to early lung disease than traditional lung function measurements. Before it can be adopted as a primary endpoint in multicentre trials, it must be demonstrated that it can be applied with minimal inter-operator variability. LCI is a major secondary outcome in our gene therapy multidose trial. Aim To assess LCI achievability and intra- and inter-site agreement. Method 136 CF patients at two sites with FEV 1 50–90% predicted were randomly allocated on a 1:1 basis to receive 12 monthly nebulised doses of active gene therapy product or placebo. LCI was performed in triplicate on seven occasions for each subject using a MBW technique completed on an Innocor TM device using 0.2% SF 6 . Stringent quality control criteria have been developed, including offset calculations and minimal acceptable differences between tests. LCI was calculated using customised offline analysis software (SimpleWashout, Igor Pro) by a single operator at each site. To test inter-operator agreement, every seventh MBW from each timepoint was randomly selected, without subject duplication, and used to calculate LCI values by both operators separately. Results A total of 854 LCIs were performed during the trial, and technically acceptable measurements were achieved in 95.9% and 94.2% of tests at the two sites (mean 94.8%). 118 (13.8%) of LCIs were analysed independently by two operators, with a full range LCI values represented (range 7.24–19.21). The 95% limits of agreement (LoA) for LCI values were -0.04 to 0.04 (mean difference 0.00) and for FRC values were -0.01 to 0.01 (mean difference 0.00). Conclusions Our results demonstrate that LCI is an achievable outcome measure in a multicentre trial in 94.8% of attempts. Separate offline analysis completed by two operators, with appropriate training and knowledge of the test, produces mean LCI and FRC inter-site differences of 0.00. LCI is feasible and appropriate for use as a surrogate endpoint in multicentre clinical trials using stringent methodology.

Importance of Spin–Orbit Coupling in Hybrid Organic/Inorganic Perovskites for Photovoltaic Applications

Three-dimensional (3D) hybrid perovskites CH3NH3PbX3 (X = Br, I) have recently been suggested as new key materials for dye-sensitized solar cells (DSSC) leading to a new class of hybrid semiconductor photovoltaic cells (HSPC). Thanks to density functional theory calculations, we show that the band gap of these compounds is dominated by a giant spin–orbit coupling (SOC) in the conduction-band (CB). At room temperature, direct and isotropic optical transitions are associated to a spin–orbit split-off band related to the triply degenerated CB of the cubic lattice without SOC. Due to the strong SOC, the electronic states involved in the optical absorption are only slightly perturbed by local distortions of the lattice. In addition, band offset calculations confirm that CH3NH3PbX3/TiO2 is a reference material for driving electrons toward the electrode in HSPC. Two-dimensional (2D) hybrids are also suggested to reach further flexibility for light conversion efficiency. Our study affords the basic concepts to re...

Carbon's Calculatory Spaces: The Emergence of Carbon Offsets in Costa Rica

This paper analyzes the practices of calculation needed to create carbon forestry offsets in Costa Rica, paying special attention to the spaces that are produced through such practices. I argue that the calculations needed to bring a carbon offset into being as a commodity is a process that results in the coconstitution of relational space, absolute Cartesian spaces, and the bounded territory of the nation-state. I develop my argument by drawing on Martin Heidegger's writings on calculation, technology, and the question of being and examine the spaces that result from carbon offset calculations performed by the Costa Rican state. Central to my argument is the idea that the practices of calculation are productive of a technological metaphysics, where the world becomes disclosed to us as an object of orderability. This ontological orientation allows for the objects and subjects of the world, in this case carbon commodities as well as producers and consumers of carbon offsets, to become relationally embedded in the world through the production of bounded Cartesian space. The production of such ‘graspable’ spaces simultaneously reinforces and undermines the territoriality of the Costa Rican state.

Address generators for linear systolic array

Systolic arrays (SAs) are very efficient architectures for multimedia processing, database management, and scientific computing applications that are characterized by a high number of data access. However, in these data transfer and storage intensive applications, memory access is often the limiting factor to the computation speed. Since the memory subsystem dominates the cost (area), performance and power consumption of the SA, we have to pay a special attention to how memory subsystem can benefit from customization. In this paper we consider memory organization of linear systolic array with bi-directional links (called BLSA) suitable for implementation of broad class of algorithms. We assume that memory is organized into distributed smaller physical memory modules. In order to provide high bandwidth in data access we have designed special hardware, called address generator unit (AGU). The function of AGU is threefold. First, during the initialization, it transforms host address space into BLSA address space. Second, provides efficient memory data access during BLSA operation. Third, performs fast data transfer between BLSA and host at the end of the computation. In this article, we examine the impact on area and performance of memory access related circuity in eliminating computational intensive offset address calculations performed in software by implementing the needed address transformations with the AGUs. By involving hardware AGUs we achieved a speedup of approximately two, compared to the software implementation of address calculation, with a hardware overhead of only 7.6% in the worst case.

Electron states in CdMnSe/ZnSe and in CdSe/ZnMnSe diluted magnetic semiconductor quantum dots

AbstractSelf‐assembed quantum dots (QDs) based on II‐VI compounds are interesting with regard to their electronic and optical properties due to their large scale provided by their fundamental gap. Among II‐VI materials, diluted magnetic semiconductor (DMS) nanostructures like CdSe/ZnMnSe and CdMnSe/ZnSe QDs are of particular interest due to the exchange interaction between the spin of the carriers and the spin of the paramagnetic Mn2+ ions located in ternary alloy layers. The application of an external magnetic field at low temperature induce the so‐called giant Zeemann effect of the band edges. In this work we first report the band offset calculations for zinc blende pseudomorphically strained CdSe/ZnSe interface. Then, we calculate the lowest electron states in both (Cd,Mn)Se/ZnSe and in CdSe/(Zn,Mn)Se QDs. Results show that the giant Zeeman splitting is more important when the Mn ions are inside the dot. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

A seismic stratigraphic analysis of Mariana forearc basin evolution

New seismic data collected in the 14.5°–18.5°N Mariana segment of the Izu‐Bonin‐Mariana island arc system image six seismic stratigraphic sequences that can be mapped throughout the inner forearc. These sediments were most likely deposited from 35 Ma to the present. The oldest stratigraphic Units 1, 2, and 3 are syn‐rift volcaniclastic deposits. Unit 4 deposits accumulated during a period of mild structural inversion, which resulted in several isolated reverse‐faulted anticlines within the forearc sedimentary basin. A late period of extensional deformation began near the end of Unit 5 deposition and continued through Unit 6 sedimentation to the present. Seismic lines show that the basement of the forearc is composed of large rotated fault blocks and half grabens with NE, NW, and NNE trends. Fault offset calculations show that basement faults with dips between 45° and 50° account for only ∼4% total extension in the forearc. South of 16.3°N, normal growth faults initiated during basement extension offset the frontal arc high from a deep forearc basin. From correlations with the known geologic history, we hypothesize that extension during deposition of Units 1 through 3 corresponds to rifting of the Eo‐Oligocene Arc, between ∼35 Ma and 29 Ma, older deposits being too thin to be seismically resolvable. Localized compression during Unit 4 accumulation occurred some time after Eo‐Oligocene rifting in the early Miocene. Late‐stage normal faulting near the end of deposition of Unit 5 and throughout Unit 6 accumulation may be associated with the opening of the Mariana Trough backarc basin from ∼8 Ma years to the present. There is a higher density of these later faults in the inner forearc between 15.5° and 17°N and in the outer forearc between 14°N and 18°N. Recent extension is at least partially accommodated by reactivation of older basement faults with the same NE, NW, and NNE‐ trends. Stratigraphic relationships indicate that the inner forearc south of 16.3°N has differentially subsided and tilted trenchward, possibly as a result of a recent change in subducting slab geometry or subducted relief under the forearc.

Band offset calculations of ZnSxSe1−x/ZnSySe1−y heterostructures

In order to design devices based on II–VI materials, it is necessary to know the potential across the interface between two materials. Following our recent calculations which prove that the band gap energy of ZnSxSe1−x alloy has a nonlinear behaviour versus the sulphur composition x, it appears that an accurate knowledge of band offsets for ZnSxSe1−x/ZnSySe1−y structures will be useful to model devices based on this heterostructure. On the basis of a model-solid theory, we report in this work the band offset calculations for zinc blende pseudomorphically strained ZnSxSe1−x/ZnSySe1−y interface. From the results obtained, we have calculated the band gap energies of ZnSxSe1−x layers pseudomorphically strained on ZnSySe1−y substrate as a function of compositions x and y in the whole range 0≤x,y≤1. Also, the band gaps of bulk ZnSxSe1−x deposed on ZnSySe1−y for several values of y have been calculated versus the sulphur content x. Analytical formulas fitting these bands have been obtained. In view of the lack of theoretical calculations, our results seem likely to be useful especially in the design of ZnSxSe1−x structures for optoelectronic devices applications.

Band offset calculations applied to III–V nitride quantum well device engineering

Band offset calculations for zinc-blende pseudomorphically strained Al 1− x Ga x N/Al 1− y Ga y N and In x Ga 1− x N/In y Ga 1− y N interfaces have been performed on the basis of the model solid theory combined with ab initio calculations. From the results obtained, we have calculated, separately, the valence and conduction band discontinuities of In x Ga 1− x N/GaN and GaN/Al 1− x Ga x N as a function of the indium and gallium contents respectively. Using the latter results, we have extended our study to simulate band discontinuities for strained Ga 1− x In x N/relaxed Al 1− y Ga y N heterointerfaces. Information derived from this investigation will be useful for the design of lattice mismatched heterostructures in modeling optoelectronic devices emitting at ultraviolet to near infrared wavelengths.

Modelling of visible and near infrared wavelength quantum well devices made of zinc-blendeInxGa1−xN

We report band offset calculations for lattice-matched and pseudomorphically strainedInxGa1−xN/InyGa1−yN heterointerfaces using the model solid theory combined with ab initiocalculations. From the results obtained, we have calculated the bandgap of bulkInxGa1−xN on GaN as a function of the indium composition. We have also simulated the band edges of anInxGa1−xN/GaN heterostructure. A self-consistent analysis is made to investigate the effect of strains on theinterband transitions with the aim of achieving emissions at both visible andnear infrared wavelengths. An attempt to explain the results obtained will bepresented.

OCB

We describe a parallelizable block-cipher mode of operation that simultaneously provides privacy and authenticity. OCB encrypts-and-authenticates a nonempty string M ∈ {0, 1}* using ⌈| M |/ n ⌉ + 2 block-cipher invocations, where n is the block length of the underlying block cipher. Additional overhead is small. OCB refines a scheme, IAPM, suggested by Charanjit Jutla. Desirable properties of OCB include the ability to encrypt a bit string of arbitrary length into a ciphertext of minimal length, cheap offset calculations, cheap key setup, a single underlying cryptographic key, no extended-precision addition, a nearly optimal number of block-cipher calls, and no requirement for a random IV. We prove OCB secure, quantifying the adversary's ability to violate the mode's privacy or authenticity in terms of the quality of its block cipher as a pseudorandom permutation (PRP) or as a strong PRP, respectively.

A Statistical Thermodynamic Model for Studying Energy Band Structure of Semiconductor Heterostructures

Advances in the science and technology of device quality semiconductor microstructures opened new directions in the making of heterojunction devices which are much faster than the conventional silicon devices. In order to fully appreciate the potantial electronic and optoelectronic applications of heterostructures there are material issues that must be fully investigated. One of the most important issues is the understanding and determination of the discontinuity in the energy band structure of the heterostructure at its interface and has received world wide interest among the device physicists and engineers over the three decades [1]. These energy band offsets affect various device properties such as the injection efficiency of heterojunction bipolar transistors (HBTs) and the carrier confinement in the recently developed modulation doped field effect transistors (MODFETs)[2]. A statistical thermodynamic model is presented to study the band offsets and temperature and strain induced nonlinearities in the band structure of lattice matched and pseudomorphic heterostructures. The model uses an average internal reference energy level (obtained using the universal tight bonding theory [3]), at which the bonding (valence-like) and antibonding (conduction-like) states are equal, to define the thermodynamic equilibrium for a heterostructure at any temperature and strain. Use of such internal reference level allows one to incorporate the effects of third nearest neighboor interactions on the band offset calculations. The temperature and strain induced nonlinear effects on the band structure is calculated by using two universal statistical thermodynamic postulates [4]: (i) The free electrons and holes are electrically charged weakly interacting quasi-chemical particles; (ii) The electron-hole pairs are generated by the charge transfer from the bonding (antibonding) states toantibonding (bonding) states in tetrahedrally coordinated semiconductors and semimetals. It is shown that there is a good agreement between the model predictions and experimental data for the band offsets and temperature and pressure induced nonlinearities in the energy bandgaps of lattice matched AlGaAs/GaAs and HgCdTe/CdTe heterostructures for over wide range of temperatures and pressures. It is also shown that in the HgTe/CdTe system, the applied pressure moves up the energy of \Gamma_{6c} antibonding states above the energy of the \Gamma_{8v} bonding states and HgTe becomes a diamond type semiconductor above certain pressure with finite bandgap. Above the transition pressure of 25 Kbar, the band alignment at the HgTe/CdTe interface transforms from type III to conventional type I.