Journal articles: 'SSPFM'

1

Nor Farihah Azman, Abdul Kadir Jumaat, Akmal Shafiq Badarul Azam, Noor Ain Syazwani Mohd Ghani, Mohd Azdi Maasar, Mohamed Faris Laham, and Normahirah Nek Abd Rahman. "Digital Medical Images Segmentation by Active Contour Model based on the Signed Pressure Force Function." Journal of Information and Communication Technology 23, no. 3 (July 28, 2024): 393–419. http://dx.doi.org/10.32890/jict2024.23.3.2.

Full text

Abstract:

The signed pressure force (SPF) function has recently become a popular function for guiding the curve evolution of the active contour model (ACM) for image segmentation. The aim is to extract the boundaries of digital medical images for shape and image analysis. The recent SPF-based ACM demonstrates effectiveness in image segmentation. However, it may fail if the targeted object is close to a neighbouring object. Additionally, the presence of intensity inhomogeneity and noise in medical images degrades segmentation accuracy and local target areas. Thus, we proposed a new SPF-based ACM, namely the Selective Segmentation with Signed Pressure Force 1 (SSPF1) model, by incorporating the ideas of the SPF function and the distance fitting term based on geometrical constraints. Then, the new SSPF1 model was extended by incorporating an image enhancement technique to develop our second new model, termed the Selective Segmentation with Signed Pressure Force 2 (SSPF2). Numerical results indicated that the SSPF2 model was more recommended than SSPF1 as the SSPF2 model was approximately 4.7% more accurate, as indicated by the Jaccard value and was about 112 times faster in segmenting noisy images compared to the existing selective segmentation model.

APA, Harvard, Vancouver, ISO, and other styles

2

Sobash, Ryan A., and John S. Kain. "Seasonal Variations in Severe Weather Forecast Skill in an Experimental Convection-Allowing Model." Weather and Forecasting 32, no. 5 (September 27, 2017): 1885–902. http://dx.doi.org/10.1175/waf-d-17-0043.1.

Full text

Abstract:

Abstract Eight years of daily, experimental, deterministic, convection-allowing model (CAM) forecasts, produced by the National Severe Storms Laboratory, were evaluated to assess their ability at predicting severe weather hazards over a diverse collection of seasons, regions, and environments. To do so, forecasts of severe weather hazards were produced and verified as in previous studies using CAM output, namely by thresholding the updraft helicity (UH) field, smoothing the resulting binary field to create surrogate severe probability forecasts (SSPFs), and verifying the SSPFs against observed storm reports. SSPFs were most skillful during the spring and fall, with a relative minimum in skill observed during the summer. SSPF skill during the winter months was more variable than during other seasons, partly due to the limited sample size of events, but was often less than that during the warm season. The seasonal behavior of SSPF skill was partly driven by the relationship between the UH threshold and the likelihood of obtaining severe storm reports. Varying UH thresholds by season and region produced SSPFs that were more skillful than using a fixed UH threshold to identify severe convection. Accounting for this variability was most important during the cool season, when a lower UH threshold produced larger SSPF skill compared to warm-season events, and during the summer, when large differences in skill occurred within different parts of the continental United States (CONUS), depending on the choice of UH threshold. This relationship between UH threshold and SSPF skill is discussed within the larger scope of generating skillful CAM-based guidance for hazardous convective weather and verifying CAM predictions.

APA, Harvard, Vancouver, ISO, and other styles

3

Sobash, Ryan A., Craig S. Schwartz, Glen S. Romine, Kathryn R. Fossell, and Morris L. Weisman. "Severe Weather Prediction Using Storm Surrogates from an Ensemble Forecasting System." Weather and Forecasting 31, no. 1 (February 1, 2016): 255–71. http://dx.doi.org/10.1175/waf-d-15-0138.1.

Full text

Abstract:

Abstract Probabilistic severe weather forecasts for days 1 and 2 were produced using 30-member convection-allowing ensemble forecasts initialized by an ensemble Kalman filter data assimilation system during a 32-day period coinciding with the Mesoscale Predictability Experiment. The forecasts were generated by smoothing the locations where model output indicated extreme values of updraft helicity, a surrogate for rotating thunderstorms in model output. The day 1 surrogate severe probability forecasts (SSPFs) produced skillful and reliable predictions of severe weather during this period, after an appropriate calibration of the smoothing kernel. The ensemble SSPFs exceeded the skill of SSPFs derived from two benchmark deterministic forecasts, with the largest differences occurring on the mesoscale, while all SSPFs produced similar forecasts on synoptic scales. While the deterministic SSPFs often overforecasted high probabilities, the ensemble improved the reliability of these probabilities, at the expense of producing fewer high-probability values. For the day 2 period, the SSPFs provided competitive guidance compared to the day 1 forecasts, although additional smoothing was needed to produce the same level of skill, reducing the forecast sharpness. Results were similar using 10 ensemble members, suggesting value exists when running a smaller ensemble if computational resources are limited. Finally, the SSPFs were compared to severe weather risk areas identified in Storm Prediction Center (SPC) convective outlooks. The SSPF skill was comparable to the SPC outlook skill in identifying regions where severe weather would occur, although performance varied on a day-to-day basis.

APA, Harvard, Vancouver, ISO, and other styles

4

K, Sathya, and Guruswamy K.P. "A Comprehensive Review: Topology, Modeling and Control Techniques of Resonant Converter for Electric Vehicle Applications." International Journal of Engineering and Advanced Technology 11, no. 5 (June 30, 2022): 125–28. http://dx.doi.org/10.35940/ijeat.e3607.0611522.

Full text

Abstract:

This paper proposes the comprehensive review on the different resonant converter topologies, different modelling techniques, and different control techniques are being used in electric vehicle application. This paper also discusses the merits and demerits of different modulation/control techniques. The performance of variable frequency control technique can be improvised using SSPM is discussed in this paper. Optimal projectory control method has a quick transient response than SSPSM followed by SSOC, then PSM, and finally by VF controller are reviewed in detail in this study. Cyclic averaging is an accurate alternative method for state variable, this approach is used for time domain analysis of resonant dc-dc converter has been emphasized in this paper. Reverberation would be beneficial when series and parallel resonance converters combined are explained in this paper. LLC topology would be best suitable for electric vehicle applications are discussed and structure of the resonant converters, power efficiency, compatibility and its suitable applications are presented in this paper. A detailed study of modelling techniques to address the increasing demand for electric vehicles are presented.

APA, Harvard, Vancouver, ISO, and other styles

5

Zhang, Bin, Qin He Sun, and Wei Tong Liu. "Thermal Performance of a Shape-Stabilized Phase Change Material Floor with Different Heating Positions." Key Engineering Materials 717 (November 2016): 62–67. http://dx.doi.org/10.4028/www.scientific.net/kem.717.62.

Full text

Abstract:

An effective method to reduce energy consumption for heating a building is by incorporating shape–stabilized phase change material (SSPCM) in building floors. In this study, a new type of SSPCM with increased thermal conductivity is formulated through a self–established experimental device. A model to analyze the thermal performance of the SSPCM floor is developed. The model is used to analyze the thermal performance of the SSPCM floor with two heating positions, one at the bottom and the other in the middle of the SSPCM. Results show that when the heating position is in the middle of the SSPCM, the melting speed is faster and the melting degree of SSPCM is larger than when it is at the bottom.

APA, Harvard, Vancouver, ISO, and other styles

6

He, Li Hong, Jing Ruo Li, and Hong Zhou Zhu. "Analysis on Application Prospect of Shape-Stabilized Phase Change Materials in Asphalt Pavement." Applied Mechanics and Materials 357-360 (August 2013): 1277–81. http://dx.doi.org/10.4028/www.scientific.net/amm.357-360.1277.

Full text

Abstract:

Blends of asphalt and shape-stabilized phase change materials (SSPCM) were prepared by physical blending. Heat storage and thermal stability of asphalt-SSPCM blends were investigated by DSC and TG, chemical compatibility of asphalt-SSPCM blends was characterized by FT-IR, and the application feasibility of SSPCM in asphalt pavement was explored. The results show that asphalt-SSPCM blends have large phase change enthalpy, good thermal stability and chemical compatibility. Based on phase change theoretical analysis and numerical calculation, SSPCM applied in asphalt pavement can actively regulate and control pavement temperature using solar energy conversion or storage, lighten the asphalt pavement diseases related temperatures, enhance the performance of and prolong the service life of asphalt pavement, lower repair and maintenance cost, and enhance driving safety. At the same time, it can also saving energy sources and protect environment. Therefore, SSPCM have broad application foregrounds in asphalt pavement.

APA, Harvard, Vancouver, ISO, and other styles

7

Zeng, Changnv, Chaoxin Hu, and Wanwan Li. "Thermal Regulation Performance of Shape-Stabilized-Phase-Change-Material-Based Prefabricated Wall for Green Grain Storage." Materials 16, no. 3 (January 20, 2023): 964. http://dx.doi.org/10.3390/ma16030964.

Full text

Abstract:

In order to meet the great demand for green grain storage and low carbon emissions, paraffin, high-density polyethylene (HDPE), and expanded graphite (EG) were used to produce shape-stabilized phase change material (SSPCM) plates, which were then used to reconstruct building walls for existing granaries. A new type of SSPCM plate was then prefabricated with different thermal conductivities and a high latent heat. This plate could be directly adhered to the existing granary walls. In order to evaluate the thermal regulation performance of these phase change granary walls, experiments and numerical methods were established, specifically for the summer condition. The thermal behavior of the SSPCM granary wall was compared with that of the common concrete granary wall to obtain the optimal parameters. It was concluded that increasing the thickness of the SSPCM layer can reduce the temperature rise of the wall. However, the maximum latent heat utilization rate and energy storage effects were obtained when the SSPCM thickness was at an intermediate level of 30 mm. The thermal conductivity of the SSPCM had a controversial effect on the thermal resistance and latent heat utilization behaviors of the SSPCM. Considering the temperature level and energy saving rate, a 30 mm thick SSPCM plate with a thermal conductivity of 0.2 W/m·K provided a superior performance. When compared to the common wall, the optimized energy-saving rate was greatly enhanced by 35.83% for the SSPCM granary wall with a thickness of 30 mm and a thermal conductivity of 0.2 W/m·K.

APA, Harvard, Vancouver, ISO, and other styles

8

Chen, Mei Zhu, Guang Ji Xu, Shao Peng Wu, and Wan Lu. "Preliminary Study on Asphalt Mortar Containing Shaped-Stabled Phase Change Material." Advanced Materials Research 306-307 (August 2011): 1702–6. http://dx.doi.org/10.4028/www.scientific.net/amr.306-307.1702.

Full text

Abstract:

The objective of this study is to investigate the preliminary feasibility on the utilization of shaped-stabled phase change materials (SSPCM) in asphalt concrete to control pavement high-temperature. A comparative study has been conducted on the properties of asphalt with and without SSPCM. The properties investigated include basic and rheological performance along with temperature-controlling effect of asphalt mortars. The results show that there exist stiffening and “temperature lag” effect for asphalt mortar containing SSPCM, which indicates that it may be promising to use SSPCM to reduce high-temperature of asphalt pavement.

APA, Harvard, Vancouver, ISO, and other styles

9

Zeng, Qibin, Celine Sim, Anna Marie Yong, Hui Kim Hui, Yunjie Chen, Lei Zhang, Chee Kiang Ivan Tan, Huajun Liu, and Kaiyang Zeng. "Emerging multi-frequency surface strain force microscopy." Journal of Applied Physics 133, no. 4 (January 28, 2023): 040901. http://dx.doi.org/10.1063/5.0131075.

Full text

Abstract:

During the past decade, Scanning Probe Microscopy (SPM) based surface strain detection techniques have been extensively used in the characterization of functional materials, structures, and devices. Here, we refer these techniques as Surface Strain Force Microscopy (SSFM), which mainly includes the Piezoresponse Force Microscopy, Atomic Force Acoustic Microscopy, Atomic Force Microscopy-Infrared spectroscopy (or photothermal induced resonance), Piezomagnetic Force Microscopy, and Scanning Joule Expansion Microscopy. The inception of SSFM opens up a pathway to study the nanoscale physical properties by using a sharp tip to detect the local field-induced surface strain. Through measuring the signals of the surface strain, multiple physical properties, such as the electromechanical, mechanical, photothermal, magnetic, thermoelastic properties, can be characterized with an unprecedented spatial resolution. In order to further develop and overcome the fundamental issues and limitations of the SSFM, the multi-frequency SPM technology has been introduced to the SSFM-based techniques, leading to the emerging of multi-frequency SSFM (MF-SSFM). As a technical breakthrough of the SSFM, MF-SSFM has demonstrated substantial improvements in both performance and capability, resulting in increased attentions and numerous developments in recent years. This Perspective is, therefore, aimed at providing a preliminary summary and systematic understanding for the emerging MF-SSFM technology. We will first introduce the basic principles of conventional SSFM and multi-frequency SPM techniques, followed by a detailed discussion about the existing MF-SSFM techniques. MF-SSFM will play an increasingly important role in future nanoscale characterization of the physical properties. As a result, many more advanced and complex MF-SSFM systems are expected in the coming years.

APA, Harvard, Vancouver, ISO, and other styles

10

Wilkenskjeld, Stiig, Frederieke Miesner, Paul P. Overduin, Matteo Puglini, and Victor Brovkin. "Strong increase in thawing of subsea permafrost in the 22nd century caused by anthropogenic climate change." Cryosphere 16, no. 3 (March 28, 2022): 1057–69. http://dx.doi.org/10.5194/tc-16-1057-2022.

Full text

Abstract:

Abstract. Most earth system models (ESMs) neglect climate feedbacks arising from carbon release from thawing permafrost, especially from thawing of subsea permafrost (SSPF). To assess the fate of SSPF in the next 1000 years, we implemented SSPF into JSBACH, the land component of the Max Planck Institute Earth System Model (MPI-ESM). This is the first implementation of SSPF processes in an ESM component. We investigate three extended scenarios from the 6th phase of the Coupled Model Intercomparison Project (CMIP6). In the 21st century only small differences are found among the scenarios, but in the upper-end emission scenario SSP5–8.5 (shared socio-economic pathway), especially in the 22nd century, SSPF ice melting is more than 15 times faster than in the pre-industrial period. In this scenario about 35 % of total SSPF volume and 34 % of SSPF area are lost by the year 3000 due to climatic changes. In the more moderate scenarios, the melting rate maximally exceeds that of pre-industrial times by a factor of 4, and the climate change induced SSPF loss (volume and area) by the year 3000 does not exceed 14 %. Our results suggest that the rate of melting of SSPF ice is related to the length of the local open-water season and thus that the easily observable sea ice concentration may be used as a proxy for the change in SSPF.

APA, Harvard, Vancouver, ISO, and other styles

11

Sass, Gabriele, Satya Kethineni, and David A. Stevens. "Anti-Fungal (Aspergillus fumigatus) Activity of Pseudomonas aeruginosa in Cystic Fibrosis Synthetic Sputum." Pathogens 13, no. 10 (October 7, 2024): 875. http://dx.doi.org/10.3390/pathogens13100875.

Full text

Abstract:

Aspergillus fumigatus (Af) and Pseudomonas aeruginosa (Pa) are pathogens inhabiting the lungs of persons with cystic fibrosis (CF), or immune-compromised patients, causing or aggravating disease. We previously investigated their microbial interaction as well as susceptibility to anti-fungal drugs using RPMI medium (contains undetectable iron concentrations), as is standard for susceptibility testing. Here we investigated microbial interaction in synthetic sputum medium (SSPM), a complex mixture designed to mimic the milieu in CF lungs. SSPM contains Fe2+. Pa laboratory strain PA14 or PA14 siderophore mutant planktonic culture filtrate, prepared in RPMI or SSPM, were compared for inhibition of Af biofilm formation. SSPM enhanced bacterial and fungal growth and the production of the Pa molecules pyoverdine, phenazines, and rhamnolipids. Af was more susceptible to these molecules in SSPM (with the exception of pyoverdine). SSPM interfered with fungal susceptibility to pyoverdine. Studies with the mutant helped to reveal that the reduced anti-fungal activity of pyoverdine in SSPM appears to be compensated by higher production of other anti-fungal molecules, e.g., rhamnolipids, phenazines, and PQS, and higher Af sensitivity to these molecules. In summary, SSPM better defines Pa–Af intermicrobial competition in the milieu of CF lungs.

APA, Harvard, Vancouver, ISO, and other styles

12

Choi, Kiho, Daejin Park, and Jeonghun Cho. "SSCFM: Separate Signature-Based Control Flow Error Monitoring for Multi-Threaded and Multi-Core Environments." Electronics 8, no. 2 (February 1, 2019): 166. http://dx.doi.org/10.3390/electronics8020166.

Full text

Abstract:

Soft error is a key challenge in computer systems. Without soft error mitigation, control flow error (CFE) can lead to system crash. Signature-based CFE monitoring scheme is a representative technique for detecting CFEs during runtime. However, most of the signature-based CFE monitoring schemes proposed thus far are based on a single thread. Currently, the widely used multi-threaded and multi-core environments have greatly improved the performance of the computing system, but, if the these schemes are applied in these environments, performance improvement is difficult to achieve, or rather performance degradation may occur. In this paper, we propose a separate signature-based CFE monitoring (SSCFM) scheme that separates the signature update and the signature verification on the thread level. The signature update is combined with application thread and signature verification and executed on separate monitor threads, so that we can expect performance improvements in multi-threaded or multi-core environments. Furthermore, the SSCFM scheme can fully cover inter-procedural CFE not covered by many signature-based CFE monitoring schemes by using inter-procedural control flow analysis. With the proposed SSCFM scheme, the execution time overhead is reduced by approximately 26.67% on average from the SEDSR scheme, and the average CFE detection rate with SSCFM is approximately 93.69%. In addition, this paper also introduces the LLVM compiler-based SSCFM generator that makes it easy to apply the SSCFM scheme to software applications.

APA, Harvard, Vancouver, ISO, and other styles

13

Jaworski, Marek. "Methods of Step-Size Distribution Optimization Used in S-SSFM Simulations of WDM Systems." Journal of Telecommunications and Information Technology, no. 1 (June 26, 2023): 44–50. http://dx.doi.org/10.26636/jtit.2009.1.913.

Full text

Abstract:

Brief review of methods used for simulation of signal propagation in wavelength division multiplexed (WDM)links is presented. We propose two novel methods of stepsize distribution optimization used to improve symmetrized split step Fourier method (S-SSFM) numerical efficiency: presimulated local error S-SSFM (PsLE S-SSFM) and modified logarithmic (ML S-SSFM). The PsLE S-SSFM contains two stages: in the initial stage step-size distribution optimization is carried out by combining local error method and presimulation with signal spectrum averaging; in the second stage conventional SSFM is used by applying optimal step-size distribution obtained in the initial stage. The ML S-SSFMis generalization of logarithmic method proposed to suppress spurious FWM tones, in which a slope of logarithmic step-size distribution is optimized. Overall time savings exceed 50%, depending of a simulated system scenario.

APA, Harvard, Vancouver, ISO, and other styles

14

Sobash, Ryan A., Glen S. Romine, and Craig S. Schwartz. "A Comparison of Neural-Network and Surrogate-Severe Probabilistic Convective Hazard Guidance Derived from a Convection-Allowing Model." Weather and Forecasting 35, no. 5 (October 1, 2020): 1981–2000. http://dx.doi.org/10.1175/waf-d-20-0036.1.

Full text

Abstract:

AbstractA feed-forward neural network (NN) was trained to produce gridded probabilistic convective hazard predictions over the contiguous United States. Input fields to the NN included 174 predictors, derived from 38 variables output by 497 convection-allowing model forecasts, with observed severe storm reports used for training and verification. These NN probability forecasts (NNPFs) were compared to surrogate-severe probability forecasts (SSPFs), generated by smoothing a field of surrogate reports derived with updraft helicity (UH). NNPFs and SSPFs were produced each forecast hour on an 80-km grid, with forecasts valid for the occurrence of any severe weather report within 40 or 120 km, and 2 h, of each 80-km grid box. NNPFs were superior to SSPFs, producing statistically significant improvements in forecast reliability and resolution. Additionally, NNPFs retained more large magnitude probabilities (>50%) compared to SSPFs since NNPFs did not use spatial smoothing, improving forecast sharpness. NNPFs were most skillful relative to SSPFs when predicting hazards on larger scales (e.g., 120 vs 40 km) and in situations where using UH was detrimental to forecast skill. These included model spinup, nocturnal periods, and regions and environments where supercells were less common, such as the western and eastern United States and high-shear, low-CAPE regimes. NNPFs trained with fewer predictors were more skillful than SSPFs, but not as skillful as the full-predictor NNPFs, with predictor importance being a function of forecast lead time. Placing NNPF skill in the context of existing baselines is a first step toward integrating machine learning–based forecasts into the operational forecasting process.

APA, Harvard, Vancouver, ISO, and other styles

15

Zhou, Yuekuan, Siqian Zheng, Hao Chen, and Guoqiang Zhang. "Thermal performance and optimized thickness of active shape-stabilized PCM boards for side-wall cooling and under-floor heating system." Indoor and Built Environment 25, no. 8 (October 5, 2016): 1279–95. http://dx.doi.org/10.1177/1420326x16671983.

Full text

Abstract:

Phase change materials (PCMs) have the potential to maintain thermal comfort of occupants while reducing the energy consumption due to their high energy storage capacity. In this paper, thermal performance of active heat conduction–enhanced shape-stabilized phase change material (HCE-SSPCM) encapsulated boards, fitted with active hot/chilled water pipes were investigated for side-wall cooling and for incorporation in an under-floor heating system. Numerical model based on finite difference method was developed to study the effect of HCE-SSPCM on annual heating/cooling energy consumption saving and indoor air relative temperature fluctuation rate reduction. Our study shows that there exists an optimal location for HCE-SSPCM according to thermal resistance value of each layer and ambient conditions. The recommended thickness and thermal conductivity of HCE-SSPCM wallboard were 30–60 mm and 1–1.5 W·m−1·K−1. Compared to the room without HCE-SSPCM boards, the maximum annual heating energy consumption saving would be 16.2%. Indoor air relative temperature fluctuation rate for heating would be reduced by 41.3%. The maximum annual cooling energy consumption saving would be 4.53%. Indoor air relative temperature fluctuation rate for cooling would be reduced by 56.2%. Our research provided scientific evidences for application of PCMs to reduce energy consumption in residential buildings without sacrificing indoor thermal comfort.

APA, Harvard, Vancouver, ISO, and other styles

16

Wei, Shih Chung, Pei Tung Yang, Frank X. Gu, Kung Bin Sung, and Chii Wann Lin. "Scanning Surface Plasmon Microscope for Sensing Lipid Array and Au Film Defect." Applied Mechanics and Materials 870 (September 2017): 21–26. http://dx.doi.org/10.4028/www.scientific.net/amm.870.21.

Full text

Abstract:

We demonstrated a scanning radially-polarized surface plasmon microscopy (SSPM) with submicron lateral resolution and high refractive index sensitivity. According to the captured images, SSPM could be used to verify the quality of deposited Au film and Au structure on surface plasmon sensing chip. The defect on the SPR chip, which disturbed the plasmonic wave around the focal point, could be easily detected by our system. Moreover, the application of SSPM in imaging lipid array was showed in this article. The 1, 2-Dioleoyl-sn-glycero-3-phosphocholine (DOPC) array was made by dip-pen nanolithography. The results indicated that SSPM system could be used in comparing the thickness of DOPC array. Because of the high sensitivity and high spatial resolution of the system, we expected the SSPM to be used in measuring the properties of nanogold array structures and apply to digital-array biosensors in nanoscale.

APA, Harvard, Vancouver, ISO, and other styles

17

Chin, Chun On, and Ying Kong Sih. "Thermal Properties of Concrete Incorporated with Shape-stable Phase Change Material." MATEC Web of Conferences 203 (2018): 06021. http://dx.doi.org/10.1051/matecconf/201820306021.

Full text

Abstract:

There has been an ever-increasing interest in concrete incorporated with shape-stable phase change material (SSPCM) in recent years for its outstanding thermal performance. In this research, PCM was incorporated into porous lightweight aggregate, namely exfoliated vermiculite to form SSPCM. SSPCMS were integrated with concrete to study their effects on thermal behaviour. Thermal testing was performed using both hot plate and KD2Pro. From the obtained results, it was observed that thermal conductivity and diffusivity reduced by 29% and 63% respectively whereas specific heat capacity increased by 40% with inclusion of SSPCMs. It was concluded that the implementation of SSPCM technology can be seen as a feasible and economical solution for energy efficient buildings.

APA, Harvard, Vancouver, ISO, and other styles

18

Sobash, Ryan A., Glen S. Romine, Craig S. Schwartz, David J. Gagne, and Morris L. Weisman. "Explicit Forecasts of Low-Level Rotation from Convection-Allowing Models for Next-Day Tornado Prediction." Weather and Forecasting 31, no. 5 (October 1, 2016): 1591–614. http://dx.doi.org/10.1175/waf-d-16-0073.1.

Full text

Abstract:

Abstract Three diagnostic fields were examined to assess their ability to act as surrogates for tornadoes in a convection-allowing ensemble system run during the spring of 2015. The diagnostics included midlevel (2–5 km AGL) updraft helicity (UH25), low-level (0–3 km AGL) updraft helicity (UH03), and low-level (1 km AGL) vertical relative vorticity (RVORT1). RVORT1 was used as a direct measure of low-level rotation strength. Each storm’s RVORT1 magnitude and near-storm environment properties were extracted from each hour’s forecasts using an object-based approach. The near-storm environments of storm objects with large magnitudes of RVORT1 were very similar to the environments identified as conducive for the development of tornadic supercells in previous proximity sounding-based studies (e.g., low lifted condensation levels and strong low-level shear). This motivated the use of RVORT1 as a direct surrogate for tornadoes, without the need to filter forecasts with environmental information. The relationship between UH25 and UH03 was also explored among the simulated storms; UH03 only exceeded UH25 in storms occurring within low-CAPE/high-shear environments, while UH03 rarely exceeded UH25 in traditional supercell environments. Next-day ensemble surrogate severe probability forecasts (E-SSPFs) for tornadoes were generated using these diagnostics for 92 forecasts, with thresholds based on the number of observed tornado reports. E-SSPFs for tornadoes using RVORT1 and UH03 were more skillful than E-SSPFs using UH25. The UH25 E-SSPFs possessed little skill, regardless of threshold or smoothing length scale. All E-SSPFs suffered from poor sharpness at skillful scales, with few forecast probabilities greater than 40%.

APA, Harvard, Vancouver, ISO, and other styles

19

Xu, Ling, Xuan Liu, and Rui Yang. "Flame Retardant Paraffin-Based Shape-Stabilized Phase Change Material via Expandable Graphite-Based Flame-Retardant Coating." Molecules 25, no. 10 (May 21, 2020): 2408. http://dx.doi.org/10.3390/molecules25102408.

Full text

Abstract:

Shape-stabilized phase change material (SSPCM) is a promising thermal energy storage material in energy-saving buildings. However, its flammability leads to a fire risk. The conventional bulk addition method has a limited flame-retardant effect. Herein, a series of surface coatings with various flame retardants were introduced to improve flame retardance of SSPCM. The results showed that all of the coatings had flame-retardant effects on SSPCM; In particular, the EG coating performed the best: the horizontal burning time was the longest, the limiting oxygen index was above 30%, the V0 classification was obtained, the peak heat release rate was sharply decreased from 1137.0 to 392.5 kW/m2 and the burning process was prolonged with the least total smoke production. The flame-retardant mechanism was discussed. As paraffin easily evaporated from the SSPCM at a moderate temperature, it caused flames. After being surface coated, the EG-based coatings first hindered the volatilization of paraffin at a moderate temperature, then expanded and formed thick porous carbon layers at a high temperature to block the transfer of combustibles, oxygen and heat between the bulk and the environment. Therefore, the surface coating strategy achieved a desirable flame-retardant level with fewer flame retardants.

APA, Harvard, Vancouver, ISO, and other styles

20

Joaquim, Andrei F., Joseph P. Maslak, and Alpesh A. Patel. "Spinal Reconstruction Techniques for Traumatic Spinal Injuries: A Systematic Review of Biomechanical Studies." Global Spine Journal 9, no. 3 (April 19, 2018): 338–47. http://dx.doi.org/10.1177/2192568218767117.

Full text

Abstract:

Study Design: Systematic literature review. Objectives: Many studies have provided evidence that short-segment posterior fixation (SSPF—1 level above and 1 below) with screws at the fracture level (SFL) are enough to achieve stability in some injury patterns, such as burst fractures, avoiding the need for circumferential reconstruction and long-segment instrumented fusion (LSIF—at least 2 levels above and 2 below). Given the potential benefits of avoiding unnecessary fusion in mobile healthy spinal segments, we performed a systematic review of biomechanical studies comparing different spinal reconstruction techniques for fractures of the thoracolumbar spine. Methods: A systematic literature review was performed in the PubMed and OVID databases of biomechanical studies comparing biomechanical differences between techniques of spine reconstructions. Results: Eight studies were included and evaluated. Five of 6 studies reported stiffness improvement with SSPF and SFL, even comparable to circumferential fusion for a burst fracture. Two studies reported that LSPF has higher stiffness and restricts range of motion better than SSPF, but inclusion of screws in the fracture level is similar to LSPF (1 study). Finally, although SSPF is less stiff than anterior reconstruction, adding a SFL in SSPF results in similar stiffness than circumferential fusion for unstable burst fractures. Conclusions: Biomechanical studies analyzed generally suggested that SFL in SSPF may improve construction stiffness, and can even be compared with long-segment fixation or circumferential reconstruction in some scenarios. This construct option may be used to enhance stiffness in selected injury patterns, avoiding the needs of an additional anterior approach.

APA, Harvard, Vancouver, ISO, and other styles

21

Cortes, Gustavo, and Judy Liu. "Analysis and Design of Steel Slit Panel Frames (SSPFs) for Seismic Areas." Engineering Journal 48, no. 1 (March 31, 2011): 1–18. http://dx.doi.org/10.62913/engj.v48i1.1001.

Full text

Abstract:

The steel slit panel frame (SSPF) system is a new seismic force-resisting system (SFRS) intended for areas of high seismicity. The main components in an SSPF are steel beams and columns and steel slit panels (SSPs). SSPs are steel plates with rows of vertical slits cut at equidistant spaces. Links (small columns) are formed between the slits. When the panel is subjected to shear load, these links behave as beams in double curvature, reaching their plastic moment capacity at both ends. Beams are simply connected to the columns in the SSPF. The SSPs provide all the stiffness, strength and energy dissipation in the system. This paper presents the design of the SSP and the SSPF system. This paper also presents two prototype buildings which were designed for a site in Los Angeles, California. Finally, a simplified model developed for analyzing SSPs is presented.

APA, Harvard, Vancouver, ISO, and other styles

22

Arasteh, Hossein, Wahid Maref, and Hamed H. Saber. "3D Numerical Modeling to Assess the Energy Performance of Solid–Solid Phase Change Materials in Glazing Systems." Energies 17, no. 15 (July 30, 2024): 3759. http://dx.doi.org/10.3390/en17153759.

Full text

Abstract:

This research investigates the energy efficiency of a novel double-glazing system incorporating solid–solid phase change materials (SSPCMs), which offer significant advantages over traditional liquid–solid phase change materials. The primary objective of this study is to develop a 3D numerical model using the finite volume method, which will be followed by a parametric study under real climatic boundary conditions. A proposed double-glazing setup featuring a 2 mm layer of SSPCM applied on the inner glass pane within the air gap is modeled and analyzed. The simulations consider various transient temperatures and ranges of the SSPCM to evaluate the energy performance of the system under different weather conditions of Miami, FL during the coldest and hottest days of the year, both in sunny and cloudy conditions. The results demonstrate a notable improvement in energy performance compared to standard double-glazing windows (DGWs), with the most efficient SSPCM configuration exhibiting a phase transition temperature and range of 25 °C and 1 °C, respectively. This configuration achieved energy savings of 24%, 26%, and 23% during summer sunny, winter sunny, and winter cloudy days, respectively, relative to DGWs during cooling and heating degree hours. However, a 3% energy loss was observed during summer cloudy days. Overall, the findings of this study have shown the potential for energy savings by incorporating SSPCM with suitable thermophysical properties into double-glazing systems.

APA, Harvard, Vancouver, ISO, and other styles

23

Shih, Yeng Fong, Wei Cheng Hou, Venkata Krishna Kotharangannagari, and Ming Gin Lee. "Effects of the Usage of Wasted Diatomite and Phase Change Materials as Partial Replacement of Cement on the Mechanical Properties of Concrete." Key Engineering Materials 847 (June 2020): 161–66. http://dx.doi.org/10.4028/www.scientific.net/kem.847.161.

Full text

Abstract:

In this study, the wasted diatomite was added to the cement mortar after heat treatment, and the potential of replacing the silica fume to prepare high-strength concrete was discussed. In addition, the diatomite was used to adsorb the polyethylene glycol (PEG) to prepare a shape-stabilized phase change material (SSPCM). Moreover, the compressive strength of concrete and its performance as a temperature-regulating building material by the addition of SSPCM were investigated. The results show that the average compressive strength of the diatomite-containing test mortar after adding a water reducing agent reaches 505.27 kg/cm2, which meets the requirements of the compressive strength of the high-strength concrete. The thermal analysis results show that the diatomite successfully adsorbs PEG and the average compressive strength of SSPCM-containing test mortar reaches 235.42 kg/cm2, which meets the basic requirements of the compressive strength of concrete. The illuminating test shows that the internal temperature of the pristine cement test mortar is mostly higher than the surface temperature. However, the test mortar prepared by adding the SSPCM has a maximum reduction of internal temperature of 2.24 °C as compared with the surface temperature. It is shown that the diatomite which adsorbed phase change material can achieve the functions of lowering the internal temperature and adjusting the temperature of building materials.

APA, Harvard, Vancouver, ISO, and other styles

24

Ning, Junjie, John Fish, Felix Trinh, Jihad Abbas, Andrew Seiwert, and Fedor Lurie. "Comparison of three pressure monitors used to measure interface pressure under compression bandages." Phlebology: The Journal of Venous Disease 35, no. 4 (July 11, 2019): 262–67. http://dx.doi.org/10.1177/0268355519862178.

Full text

Abstract:

Background Measuring the interface pressure produced by compression therapy devices is essential for research and clinical practice. New user-friendly measuring devices, such as Smart Sleeve Pressure Monitor (SSPM) and Juzo Pressure Monitor (JPM) allow longitudinal pressure measurement. However, their accuracy and agreement with well-established usage of the PicoPress (PP) are unknown. The aim of this study is to investigate measurement accuracy of PP, SSPM, and JPM. Methods The three devices were tested in 10 healthy volunteers by applying incrementally increasing pressure from 20 mm Hg to 50 mm Hg using a calibrated sphygmomanometer cuff. The linearity of the response and measurement accuracy were compared among the three devices. In a separate experiment, the three devices were compared by simultaneously recording the interface pressure under bandages immediately after bandaging and after 4 h of wearing the bandage. Results PP had the best performance with the reference of sphygmomanometer, while JPM had better linearity and accuracy than SSPM. The mean difference in the interface pressure under bandages was +13.36 mm Hg between SSPM and PP, and +0.50 mm Hg between JPM and PP. The 95% limits of agreement were −13.92 and +40.64 mm Hg, and −19.83 and +20.84 mm Hg, respectively. Conclusions JPM showed better agreement with both sphygmomanometer and PP compared to SSPM. JPM is a reasonable alternative for monitoring interface pressure continuously.

APA, Harvard, Vancouver, ISO, and other styles

25

Ferreiro Garcia, Ramon. "Prototyping Self-Sustaining Power Machines with Cascaded Power Units Composed by Pulse Gas Turbines." JOURNAL OF ADVANCES IN PHYSICS 22 (August 3, 2024): 185–211. http://dx.doi.org/10.24297/jap.v22i.9648.

Full text

Abstract:

This research work aims at designing a prototype of a disruptive Self-Sustaining Power Machine (SSPM) composed of cascaded power units (PUs). Each PU consists of a Pulse Gas Turbine (PGT). The prototyping design task involves a singular thermal cycle (sVsVs) associated to each PU, characterized by doing work by: of a Thermal Working Fluid (TWF) due to previous heat addition, contraction of a TWF previously cooled by heat extraction and, upgrading recovered heat by increasing thermal potential by heat superposition techniques, and efficiexpansion ent use of the heat recovered from each upstream PU to feed the first PU downstream. The fact of achieving useful mechanical work with the above-mentioned procedures by adding only heat to produce expansion work, undergoes an excess of useful mechanical work greater than the amount of added heat, which gives rise to a SSPM enabled to defy Perpetual Motion Machines (PMM) of second kind. In the proposed configuration, the heat released from each PU due to the cooling of the TWF is efficiently recovered and reused in the first PU in the cascade. Results have been verified through two case studies carried out on a SSPM simulated prototype, being conducted using air and helium as real gases. According to the results, the SSPM composed by a group of cascaded PUs, each exhibiting an average efficiency of less than 35% with air as TWF, can approach a SSI of 22% while the SSPM composed by a group of cascaded PUs, each exhibiting an average efficiency of less than 57% with helium as TWF, can approach a SSI of 84 %. Consequently, the results achieved from the case studies of the SSPM indicate that it is possible to overcome second kind PMMs.

APA, Harvard, Vancouver, ISO, and other styles

26

Salafuddin, Ahmad, De Rosal Ignatius Moses Setiadi, Desi Purwanti Kusumaningrum, Eko Hari Rachmawanto, and Christy Atika Sari. "Pengembangan Website Radio SSFM Semarang dengan Codeigniter Berbasis Model View Controller." Eksplora Informatika 8, no. 1 (September 28, 2018): 36. http://dx.doi.org/10.30864/eksplora.v8i1.145.

Full text

Abstract:

Radio SSFM Semarang merupakan salah satu radio yang pernah populer di Semarang. Radio ini merupakan salah satu anak perusahaan Suara Merdeka grup. Radio SSFM Semarang perlu dikembangkan kembali agar dapat bersaing dengan radio lain. Salah satu yang perlu dikembangkan adalah website radio SSFM. Website ini sebelumnya hanya digunakan untuk melakukan streaming dan dibuat dengan PHP biasa yang belum menggunakan framework sehingga akan sulit dilakukan maintenance. Penelitian ini melakukan perancangan ulang untuk membuat perubahan yang signifikan pada website, sehingga penyiaran juga dapat dilakukan dengan sistem berbasis web yang modern, kreatif dan inovatif. Framework Codeigniter dan metode Model View Controller (MVC) diusulkan untuk mengimplementasikan website SSFM Semarang. Penggunaan framework Codeigniter dan metode MVC diusulkan agar website dapat lebih mudah dipelihara, cepat, andal dan mudah diakses. Website yang telah dibangun telah diuji dengan metode black-box dan uji performa dengan pengukuran waktu load website. Hasil pengujian menunjukkan bahwa penggunaan metode MVC dapat meningkatkan performa kecepatan load website. Dengan hasil pengembangan website ini diharapkan developer tidak perlu banyak dalam melakukan perubahan kode saat melakukan maintenance karena website sudah terstruktur dengan metode MVC.

APA, Harvard, Vancouver, ISO, and other styles

27

Nicholas, Ahmad, Mohd Hussein, Zulkarnain Zainal, and Tumirah Khadiran. "Palm Kernel Shell Activated Carbon as an Inorganic Framework for Shape-Stabilized Phase Change Material." Nanomaterials 8, no. 9 (September 5, 2018): 689. http://dx.doi.org/10.3390/nano8090689.

Full text

Abstract:

The preparation of activated carbon using palm kernel shells as the precursor (PKSAC) was successfully accomplished after the parametric optimization of the carbonization temperature, carbonization holding time, and the ratio of the activator (H3PO4) to the precursor. Optimization at 500 °C for 2 h of carbonization with 20% H3PO4 resulted in the highest surface area of the activated carbon (C20) of 1169 m2 g−1 and, with an average pore size of 27 Å. Subsequently, the preparation of shape-stabilized phase change material (SSPCM-C20) was done by the encapsulation of n-octadecane into the pores of the PKSAC, C20. The field emission scanning electron microscope images and the nitrogen gas adsorption-desorption isotherms show that n-octadecane was successfully encapsulated into the pores of C20. The resulting SSPCM-C20 nano-composite shows good thermal reliability which is chemically and thermally stable and can stand up to 500 melting and freezing cycles. This research work provided a new strategy for the preparation of SSPCM material for thermal energy storage application generated from oil palm waste.

APA, Harvard, Vancouver, ISO, and other styles

28

Recknor, Christopher P., Daniel Van Dussen, Norma MacIntyre, and Julie Recknor. "Functional risk for fracture by safe functional motion testing: a short version of the safe functional motion test." Therapeutic Advances in Musculoskeletal Disease 11 (January 2019): 1759720X1985601. http://dx.doi.org/10.1177/1759720x19856012.

Full text

Abstract:

Background: ‘Unsafe’ movement strategies used to perform everyday activities were quantified using scores for tasks included in the Short Form Safe Functional Motion test series (SSFM). Baseline scores were independently associated with incident fractures after adjusting for factors known to effect fracture risk. The purpose of the present study is to determine whether the SSFM, a series of tests of habitual motion, is associated with incident fragility fracture at any skeletal sites. Methods: An osteoporosis clinic database was queried for adults with baseline SSFM scores and corresponding data for prevalent fractures, femoral neck bone mineral density (fnBMD), osteoporosis medication use, and incident fractures at 1-year and 3-year follow ups [ n = 1700 (118 incident fractures) and n = 1058 (202 incident fractures), respectively]. Multiple logistic regressions, adjusted for sex, age, fnBMD, osteoporosis medication use, and any prevalent fractures at baseline, were used to determine whether baseline SSFM scores were associated with incident fragility fractures. Results: An Sfm-3 score was a significant independent predictor of any fracture at 1 year [adjusted odds ratio (95% CI) = 1.118 (1.025, 1.219) for each 10-point decrease in Sfm-3; p = 0.012], and 3-year follow up [adjusted odds ratio (95% CI) = 1.183 (1.098, 1.274) for each 10-point decrease in Sfm-3; p < 0.0001]. Conclusions: Scores on the SSFM predict fracture risk such that for each 10-point drop in score the odds of fracture are increased by up to 18% independent of risk associated with age, bone mineral density, use of bone-sparing medications, and history of a fracture.

APA, Harvard, Vancouver, ISO, and other styles

29

Stapels, Christopher J., Paul Barton, Erik B. Johnson, David K. Wehe, Purushottam Dokhale, Kanai Shah, Frank L. Augustine, and James F. Christian. "Recent developments with CMOS SSPM photodetectors." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 610, no. 1 (October 2009): 145–49. http://dx.doi.org/10.1016/j.nima.2009.05.120.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Xiao, Si, Hao Xin, HaiMing Ma, Chang Wang, Ying Ma, and Jun He. "Nonlinear optical properties of spherical MoS₂/TiO₂ composite at visible wavelengths." Journal of Physics D: Applied Physics 55, no. 25 (March 31, 2022): 254002. http://dx.doi.org/10.1088/1361-6463/ac5af7.

Full text

Abstract:

Abstract Optical nonlinear absorption and refraction of spherical MoS2/TiO2 nanocomposites were measured using Z-scan and spatial self-phase modulation (SSPM) at different wavelengths. The linear absorption spectra showed that MoS2/TiO2 nanocomposite had obvious absorption at 500–700 nm, which was mainly attributed to the shape of MoS2 and demonstrated by the finite-difference time-domain method. For nonlinear absorption, MoS2/TiO2 composite showed enhanced two-photon absorption with high photon energy excitation (400 nm), and a tunable saturated single-photon absorption with low photon energy excitation (700 nm). For nonlinear refraction, it had no SSPM signal with short wavelength, but enhanced SSPM signal with long wavelength in visible band. These unconventional phenomena can be explained by the change of main absorber and the reversal of carriers transfer direction together.

APA, Harvard, Vancouver, ISO, and other styles

31

Stephens, Scott L., Danny L. Fry, Brandon M. Collins, Carl N. Skinner, Ernesto Franco-Vizcaíno, and Travis J. Freed. "Fire-scar formation in Jeffrey pine – mixed conifer forests in the Sierra San Pedro Mártir, Mexico." Canadian Journal of Forest Research 40, no. 8 (August 2010): 1497–505. http://dx.doi.org/10.1139/x10-083.

Full text

Abstract:

Little is known about the probability of fire-scar formation. In this study, we examined all mixed conifer trees for fire-scar formation in a 16 ha watershed that burned as part of a 2003 wildfire in Sierra San Pedro Mártir National Park (SSPM), Mexico. In addition, we examine the probability of fire-scar formation in relation to the previous fire interval in forests in the SSPM and Sierra Nevada. Within the 16 ha SSPM watershed, 1647 trees were assessed (100% census) for new fire scars. The SSPM wildfire burned around the base of 78% of the trees, but only 8% developed a new fire scar. Although the years from tree germination to first fire scar could potentially represent a fire-free period, there is clear evidence from this study that the inclusion of this interval when computing fire statistics is not justified. When the time since previous fire was <10 years, 10–30 years, and >57 years, the probability of rescarring was approximately 0.05, 0.5, and 0.75, respectively. In areas where fires were frequent (<10 years), fire frequencies derived from fire scars will likely underestimate true fire frequency, at least in forests that are similar to those studied here.

APA, Harvard, Vancouver, ISO, and other styles

32

Dabas, Bhawana, Jivesh Kaushal, Monika Rajput, and R. K. Sinha. "Study of Self Phase Modulation in Chalcogenide Glass Photonic Crystal Fiber." Applied Mechanics and Materials 110-116 (October 2011): 53–56. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.53.

Full text

Abstract:

In this paper, Self Phase Modulation (SPM) in chalcogenide As2Se3glass Photonic Crystal Fiber (PCF) is numerically studied by combining the fully vectorial effective index method (FVEIM) and Split Step Fourier Method (SSFM). The FVEIM is used to calculate the variation of effective refractive index of guided mode (neff), effective area (Aeff), dispersion and non-linear coefficient (γ) with wavelength for different designs of chalcogenide As2Se3PCF. The FVEIM solves the vector wave equations and SSFM solves non linear Schrödinger Equation (NLSE) for the different designing parameter of As2Se3PCF. In case of Self Phase Modulation (SPM), spectral width of the obtained output pulse at d/Λ=0.7 is 1.5 times greater than width of the output pulse obtained at d/L=0.3 using SSFM. Thus we can get the desired spectral broadening just by tailoring the design parameters of the PCF.

APA, Harvard, Vancouver, ISO, and other styles

33

Wu, Yanling, Qiong Wu, Fei Sun, Cai Cheng, Sheng Meng, and Jimin Zhao. "Emergence of electron coherence and two-color all-optical switching in MoS2 based on spatial self-phase modulation." Proceedings of the National Academy of Sciences 112, no. 38 (September 8, 2015): 11800–11805. http://dx.doi.org/10.1073/pnas.1504920112.

Full text

Abstract:

Generating electron coherence in quantum materials is essential in optimal control of many-body interactions and correlations. In a multidomain system this signifies nonlocal coherence and emergence of collective phenomena, particularly in layered 2D quantum materials possessing novel electronic structures and high carrier mobilities. Here we report nonlocal ac electron coherence induced in dispersed MoS2 flake domains, using coherent spatial self-phase modulation (SSPM). The gap-dependent nonlinear dielectric susceptibility χ(3) measured is surprisingly large, where direct interband transition and two-photon SSPM are responsible for excitations above and below the bandgap, respectively. A wind-chime model is proposed to account for the emergence of the ac electron coherence. Furthermore, all-optical switching is achieved based on SSPM, especially with two-color intraband coherence, demonstrating that electron coherence generation is a ubiquitous property of layered quantum materials.

APA, Harvard, Vancouver, ISO, and other styles

34

Mehrali, Mohammad, Sara Tahan Latibari, Marc A. Rosen, Amir Reza Akhiani, Mohammad Sajad Naghavi, Emad Sadeghinezhad, Hendrik Simon Cornelis Metselaar, Majeed Mohammadi Nejad, and Mehdi Mehrali. "From rice husk to high performance shape stabilized phase change materials for thermal energy storage." RSC Advances 6, no. 51 (2016): 45595–604. http://dx.doi.org/10.1039/c6ra03721f.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Marco-Gisbert, Héctor, and Ismael Ripoll-Ripoll. "SSPFA: effective stack smashing protection for Android OS." International Journal of Information Security 18, no. 4 (January 22, 2019): 519–32. http://dx.doi.org/10.1007/s10207-018-00425-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Can, Erol, and H. Hüseyin Sayan. "A novel SSPWM controlling inverter running nonlinear device." Electrical Engineering 100, no. 1 (November 21, 2016): 39–46. http://dx.doi.org/10.1007/s00202-016-0480-4.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Syed Ahmad Faizan, Naeem-ul-Hassan, Zubair Mustafa Khan, Tariq Imran, and Abdul Majid. "Comparison of Short Segment Percutaneous Transpedicular Fixation With and Without Inclusion of Fractured Vertebrae in Thoracolumbar Fractures." Pakistan Journal Of Neurological Surgery 26, no. 2 (July 17, 2022): 183–93. http://dx.doi.org/10.36552/pjns.v26i2.683.

Full text

Abstract:

Objective: To compare the outcome of SSPF (Short Segment Posterior Fixation) with and without the inclusion of fractured vertebrae in thoracolumbar fractures in terms of visual analog score and vertebral column stability. Materials and Methods: The study enrolled 96 patients who were divided into two groups. Group A treated by SSPF (four screws: one level above and below the fracture), and Group B was treated by PSFFV (six screws: including fractured vertebrae). Assessment of parameters related to clinical and radiological aspects was recorded at 3 – 6 months. Results: Mean ages of patients were 36.96 and 37.41 years with an M:F ratio of 1.8:1 and 1.4:1 in groups A (SSPF) and B (PSFFV), respectively. Mean VAS preoperatively, and postoperatively, at 3 and 6 months were 8.78 vs. 9.01, 4.98 vs. 5.01, 2.08 vs. 2.11, and 0.47 vs. 0.67 in groups A and B, respectively. Mean Kyphotic angle preoperatively, postoperatively, at 3 and 6 months were 21.76 vs. 22.91, 11.13 vs. 10.16, 13.59vs. 11.16 and 14.88 vs. 12.87 in groups A and B respectively. Mean AVH preoperatively, and postoperatively, at 3 and 6 months were 19.11 vs. 18.72, 20.01 vs. 22.71, 20.61 vs. 22.87, and 20.02 vs. 22.67 in groups A and B, respectively. Conclusion: The results of this study favor PSFFV (Group B) over SSPF (Group A) in terms of vertebral column stability which was better achieved in PSFFV. PSFFV was also found superior with no implant failure which declares it safer and more effective than SSPF. None of the techniques was found superior in terms of pain. Radiologically, PSFFV, showed significant improvement in achieving anterior vertebral height, while there was no important distinction in kyphotic angle between the two.

APA, Harvard, Vancouver, ISO, and other styles

38

Zhu, Xiaofeng, and Yan Yue. "Study on Winding Inductances in Stator Surface-Mounted Permanent Magnet Machines." Energies 17, no. 21 (October 28, 2024): 5359. http://dx.doi.org/10.3390/en17215359.

Full text

Abstract:

Winding inductance always plays a key role in the electromagnetic performances of stator surface-mounted permanent magnet (SSPM) machines, including their flux-weakening capability, prospective fault current, power factor, current ripple, etc. Generally speaking, winding inductance mainly comprises three components: an air-gap component, a slot-leakage component, and an end-leakage component. In this paper, firstly, the winding pole pairs of SSPM machines are investigated based on the magneto-motive force-permeance model, through which the winding configurations can also be determined. Then, according to the winding configurations, three analytical expressions for each inductance component are derived to evaluate the winding inductance per phase. In addition, finite element analysis (FEA) is employed to verify the effectiveness of the derived analytical expressions. Meanwhile, three prototyped SSPM machines are manufactured, and their winding inductances are measured to further verify the analytical expressions. The measured results agree with both the analytical and FEA results very well.

APA, Harvard, Vancouver, ISO, and other styles

39

Zhu, Yifei, Shotaro Kitajima, and Norihiko Nishizawa. "A Fast Prediction Framework for Multi-Variable Nonlinear Dynamic Modeling of Fiber Pulse Propagation Using DeepONet." Applied Sciences 14, no. 18 (September 11, 2024): 8154. http://dx.doi.org/10.3390/app14188154.

Full text

Abstract:

Traditional femtosecond laser modeling relies on the iterative solution of the Nonlinear Schrödinger Equation (NLSE) using the Split-Step Fourier Method (SSFM). However, SSFM’s high computational complexity leads to significant time consumption, particularly in automatic control and system optimization, thus limiting control model responsiveness. Recent studies have suggested using neural networks to simulate fiber dynamics, offering faster computation and lower costs. In this study, we introduce a novel fiber propagation method utilizing the DeepONet architecture for the first time. By separately managing fiber parameters and input–output pulses in the branch and trunk networks, this method can simulate various fiber configurations with high accuracy and without altering the architecture. Additionally, while SSFM generation time increases linearly with fiber length, the GPU-accelerated AI generation time remains consistent at around 0.0014 s, regardless of length. Notably, in high-order soliton (HOS) compression over a 12 m distance, the AI method is approximately 56,865 times faster than SSFM.

APA, Harvard, Vancouver, ISO, and other styles

40

Ekwe, C. C., I. Nwabueze, and D. N. Onunkwo. "Comparative effect of feeding sundried sweet potato (Ipomoea batatas (L) Lam) meal and its whole meal to weaner rabbits." Nigerian Journal of Animal Production 46, no. 4 (December 25, 2020): 179–84. http://dx.doi.org/10.51791/njap.v46i4.287.

Full text

Abstract:

An experiment was conducted to evaluate the comparative effect of feeding sundried sweet potato and its whole meal to weaner rabbits. The proximate analysis conducted revealed that sundried sweet potato meal and whole sundried sweet potato meal samples were rather low in protein contents as compared to maize. Twenty seven Weaner rabbits averaging 0.35kg were randomly allotted to 3 treatment groups in a completely randomized design. Each treatment group was replicated 3 times. Sundried Sweet potato meal and its whole meal replaced maize at 20% inclusion level. Treatments 1, 2, and 3 contained the control, sundried sweet potato meal (SSPM) and whole sundried sweet potato meal (WSSPM) respectively at 20% levels of inclusion. The weaner rabbits were fed ad-libitum throughout the experimental period. Significant differences (p<0.05) were observed for growth performance of the rabbits in average daily weight gain, average daily feed intake and feed conversion ratio in the weaner rabbits using sundried sweet potato and its whole meal. The values of mean daily weight gain ranged from 16.33g in treatment 2 (SSPM) to 18.47g in treatment 1 (control). Treatment 3 (WSSPM) gave a higher value that is comparable (p>0.05) to that of the control diet but better (p<0.05) than that of treatment 3 (SSPM). The values of average daily feed intake also ranged from 43g in treatment 2 (SSPM) to 50g in treatment 1 (control). WSSPM was consumed more than (p<0.05) than the SSPM which however influenced the cost of total feed consumed. Moreover, the values of feed conversion ratio (FCR) ranged from 2.54 in treatment 3 (WSSPM) to 2.70 in treatment 1 (control). Significant differences (p<0.05) were also observed in bio-economics of production of weaner rabbits using the test diets. The cost per kg feed, cost of total feed consumed per rabbit, cost per kg weight gain and revenue of the rabbits fed the test diets were significantly lower than the control diet however, the cost per kg weight gain was lower (p<0.05) for treatment 3 (WSSPM). For gross margin, WSSPM value was significantly higher (p<0.05) than SSPM value and the control diet. It was concluded that whole sundried sweet potato meal can be a good feed ingredient in rabbit diet.

APA, Harvard, Vancouver, ISO, and other styles

41

Costanzo, Eliana, Daniela Giannini, Daniele De Geronimo, Serena Fragiotta, Monica Varano, and Mariacristina Parravano. "Prognostic Imaging Biomarkers in Diabetic Macular Edema Eyes Treated with Intravitreal Dexamethasone Implant." Journal of Clinical Medicine 12, no. 4 (February 6, 2023): 1303. http://dx.doi.org/10.3390/jcm12041303.

Full text

Abstract:

Background: The aim was to evaluate predictive value of baseline optical coherence tomography (OCT) and OCT angiography (OCTA) parameters in diabetic macular edema (DME) treated with dexamethasone implant (DEXi). Methods: OCT and OCTA parameters were collected: central macular thickness (CMT), vitreomacular abnormalities (VMIAs), intraretinal and subretinal fluid (mixed DME pattern), hyper-reflective foci (HRF), microaneurysms (MAs) reflectivity, ellipsoid zone disruption, suspended scattering particles in motion (SSPiM), perfusion density (PD), vessel length density, and foveal avascular zone. Responders’ (RES) and non-responders’ (n-RES) eyes were classified considering morphological (CMT reduction ≥ 10%) and functional (BCVA change ≥ 5 ETDRS letters) changes after DEXi. Binary logistic regression OCT, OCTA, and OCT/OCTA-based models were developed. Results: Thirty-four DME eyes were enrolled (18 treatment-naïve). OCT-based model combining DME mixed pattern + MAs + HRF and OCTA-based model combining SSPiM and PD showed the best performance to correctly classify the morphological RES eyes. In the treatment-naïve eyes, VMIAs were included with a perfect fit for n-RES eyes. Conclusion: The presence of DME mixed pattern, a high number of parafoveal HRF, hyper-reflective MAs, SSPiM in the outer nuclear layers, and high PD represent baseline predictive biomarkers for DEXi treatment responsiveness. The application of these models to treatment-naïve patients allowed a good identification of n-RES eyes.

APA, Harvard, Vancouver, ISO, and other styles

42

Jeannin, Jean-Michel. "21. Hauptversammlung der SMGP/ SSPM in Neuchâtel." Forschende Komplementärmedizin / Research in Complementary Medicine 17, no. 3 (2010): 164–65. http://dx.doi.org/10.1159/000318215.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Cipiti, Benjamin B., and Nathan Shoman. "Bulk Handling Facility Modeling and Simulation for Safeguards Analysis." Science and Technology of Nuclear Installations 2018 (October 4, 2018): 1–6. http://dx.doi.org/10.1155/2018/3967621.

Full text

Abstract:

The Separation and Safeguards Performance Model (SSPM) uses MATLAB/Simulink to provide a tool for safeguards analysis of bulk handling nuclear processing facilities. Models of aqueous and electrochemical reprocessing, enrichment, fuel fabrication, and molten salt reactor facilities have been developed to date. These models are used for designing the overall safeguards system, examining new safeguards approaches, virtually testing new measurement instrumentation, and analyzing diversion scenarios. The key metrics generated by the models include overall measurement uncertainty and detection probability for various material diversion or facility misuse scenarios. Safeguards modeling allows for rapid and cost-effective analysis for Safeguards by Design. The models are currently being used to explore alternative safeguards approaches, including more reliance on process monitoring data to reduce the need for destructive analysis that adds considerable burden to international safeguards. Machine learning techniques are being applied, but these techniques need large amounts of data for training and testing the algorithms. The SSPM can provide that training data. This paper will describe the SSPM and its use for applying both traditional nuclear material accountancy and newer machine learning options.

APA, Harvard, Vancouver, ISO, and other styles

44

Aguilera-Molina, Víctor M., Khutzy K. Munguía-Ortega, Eulogio López-Reyes, Andrés Martínez-Aquino, and F. Sara Ceccarelli. "Climate change and forest plagues: assessing current and future impacts of diprionid sawflies on the pine forests of north-western Mexico." PeerJ 7 (July 16, 2019): e7220. http://dx.doi.org/10.7717/peerj.7220.

Full text

Abstract:

The imminent threat of climate change lies in its potential to disrupt the balance of ecosystems, particularly vulnerable areas such as mountain-top remnant forests. An example of such a fragile ecosystem is the Sierra San Pedro Mártir (SSPM) National Park of Mexico’s Baja California state, where high levels of endemism can be found, and which is home to one of the country’s few populations of the emblematic Jeffrey pine (Pinus jeffreyi). Recent outbreaks of pine-feeding sawfly larvae in SSPM increase the vulnerability of this forest ecosystem, calling for immediate assessments of the severity of this threat. Here, we present a thorough study of the sawfly’s biology and distribution, carrying out molecular and morphology-based identification of the species and creating model-based predictions of the species distribution in the area. The sawfly was found to belong to an undescribed species of the genus Zadiprion (family Diprionidae) with a one-year life-cycle. The distribution of this species appears to be restricted to the SSPM national park and it will probably persist for at least another 50 years, even considering the effects of climate change.

APA, Harvard, Vancouver, ISO, and other styles

45

Kim, Sug-Hwan, Su-Gwang Jeong, Jae-Han Lim, and Su-Min Kim. "Preparation and Thermal Characteristics of Hexadecane/xGnP Shape-stabilized Phase Change Material for Thermal Storage Building Materials." Journal of the Korean Solar Energy Society 33, no. 1 (February 28, 2013): 73–78. http://dx.doi.org/10.7836/kses.2013.33.1.073.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Stapels, Christopher J., Erik B. Johnson, Xiao J. Chen, Thomas H. Prettyman, Eric R. Benton, and James F. Christian. "Space neutron spectrometer design with SSPM-based instrumentation." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 652, no. 1 (October 2011): 342–46. http://dx.doi.org/10.1016/j.nima.2010.10.050.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Zhang, Lei, Jiao Qun Zhu, and Wei Bing Zhou. "Heat Transfer and Electric Insulation Enhancement of Organic Shape Stabilized Phase Change Materials Using Diamond Particles." Advanced Materials Research 347-353 (October 2011): 2764–67. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.2764.

Full text

Abstract:

In this work, diamond particle (DP), based on its excellent heat transfer property as well as electric insulativity, was adopted to enhance the thermal conductivity (k) and volume resistivity (ρ)of organic shape stabilized phase change material (SSPCM) for the first time. Using the method of in situ polymerization, PMMA serving as the supporting material and PEG acting as the PCM were compounded with the DP. Results show that the DP is physically combined with PMMA/PEG matrix, and all the samples remain solid without leakage above the melting point of the PEG. The k and ρ of the composite SSPCM obviously increased with the increase of DP content. When the mass fraction of DP is increased to 30%, the k and ρ of composite achieved 0.454 W•(m•K)-1and 6.12×1010Ω•cm, respectively. It is also indicated that all the specimens provide available thermal energy storage density and thermal stability.

APA, Harvard, Vancouver, ISO, and other styles

48

Neupane, Tikaram, Bagher Tabibi, Wan-Joong Kim, and Felix Jaetae Seo. "Spatial Self-Phase Modulation in Graphene-Oxide Monolayer." Crystals 13, no. 2 (February 4, 2023): 271. http://dx.doi.org/10.3390/cryst13020271.

Full text

Abstract:

The spatial self-phase modulation (SSPM) of the optical field revealed the magnitude and polarity of nonlinear refraction coefficients of the graphene-oxide (GO) atomic layers in an aqueous base solution with a resonant excitation using a chopped quasi-static laser at 532 nm. The SSPM of the optical field as a result of the intrinsic nonlinear refraction coefficient of GO atomic layers and the spatial distribution of intensity displayed the concentric diffraction rings at the far field due to the coherent superposition of transverse wave vectors. The number of concentric rings as a function of the applied intensity revealed the nonlinear refraction coefficient of GO which was estimated to be ~–6.65 × 10−12 m2/W for the laser-excitation duration of ~0.32 s, where the negative polarity of nonlinear refraction coefficient was confirmed with the interference image profile of SSPM. The upper and vertical distortion of concentric rings at the far field at the longer laser-excitation duration of ~0.8 s indicates the distortion of the coherent superposition of transverse wave vectors due to the localized thermal vortex of GO in the aqueous solution that offers novel platforms of thermal metrology based on localized optical nonlinearity and temperature-sensitive all-optical switching.

APA, Harvard, Vancouver, ISO, and other styles

49

Kalinin, Sergei V., and Dawn A. Bonnell. "Artifacts and Non-Local Effects in SPM Potential Measurements." Microscopy Today 10, no. 4 (July 2002): 16–21. http://dx.doi.org/10.1017/s1551929500058156.

Full text

Abstract:

In the last few years Scanning Probe Microscopy (SPM) has become one of the primary tools of science and technology. In addition to topographical imaging, surface potential, conductivity, optical, ferroelectric and magnetic properties that can be studied down to the nanometer level. However, quantitative and sometimes qualitative studies of fundamental physical phenomena in meso- and nanoscale systems are often hindered by SPM imaging artifacts. Here we briefly discuss the principles of operation and the major sources of artifacts in electrostatic measurements by SPM.One of the most well known techniques for local potential imaging is Scanning Surface Potential Microscopy (SSPM). SSPM is based on dual pass imaging. The grounded tip acquires surface topography during the first pass.

APA, Harvard, Vancouver, ISO, and other styles

50

Sobash, Ryan A., John S. Kain, David R. Bright, Andrew R. Dean, Michael C. Coniglio, and Steven J. Weiss. "Probabilistic Forecast Guidance for Severe Thunderstorms Based on the Identification of Extreme Phenomena in Convection-Allowing Model Forecasts." Weather and Forecasting 26, no. 5 (October 1, 2011): 714–28. http://dx.doi.org/10.1175/waf-d-10-05046.1.

Full text

Abstract:

Abstract With the advent of convection-allowing NWP models (CAMs) comes the potential for new forms of forecast guidance. While CAMs lack the required resolution to simulate many severe phenomena associated with convection (e.g., large hail, downburst winds, and tornadoes), they can still provide unique guidance for the occurrence of these phenomena if “extreme” patterns of behavior in simulated storms are strongly correlated with observed severe phenomena. This concept is explored using output from a series of CAM forecasts generated on a daily basis during the spring of 2008. This output is mined for the presence of extreme values of updraft helicity (UH), a diagnostic field used to identify supercellular storms. Extreme values of the UH field are flagged as simulated “surrogate” severe weather reports and the spatial correspondence between these surrogate reports and actual observed severe reports is determined. In addition, probabilistic forecasts [surrogate severe probabilistic forecasts (SSPFs)] are created from each field’s simulated surrogate severe reports using a Gaussian smoother. The simulated surrogate reports are capable of reproducing the seasonal climatology observed within the field of actual reports. The SSPFs created from the surrogates are verified using ROC curves and reliability diagrams and the sensitivity of the verification metrics to the smoothing parameter in the Gaussian distribution is tested. The SSPFs produce reliable forecast probabilities with minimal calibration. These results demonstrate that a relatively straightforward postprocessing procedure, which focuses on the characteristics of explicitly predicted convective entities, can provide reliable severe weather forecast guidance. It is anticipated that this technique will be even more valuable when implemented within a convection-allowing ensemble forecasting system.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'SSPFM'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles