Evaluation of Lime as an Additive to Soil-Asphalt Stabilization, HR-1, Progress Report, 1961

This report presents the results of a limited investigation of the use of lime as an auxiliary additive for improving the stabilization of soils with cutback asphalts. It is felt that the data obtained presents additional information on the subject of asphalt stabilization

Pinpointing Suspect Triplicate Unconfined Compressive Strength Values in a Series of Soil-Additive Strength Determinations, HR-1, Progress Report, 1961

In recent years, various types of organic and inorganic materials have been investigated for use as soil stabilizing agents in the construction of highways and airports. Since the properties and environmental conditions of soils vary so greatly from place to place, a stabilizing agent that is suitable for one type of soil may not be satisfactory for another. As a result, it is often desirable to evaluate several stabilizing agents under varying treatment conditions before deciding on a specific one to be used with a given soil. In addition many research programs have been initiated which investigate the effects of these stabilizing agents upon soils.

3D noise power spectrum applied on clinical mdct scanners: effects of reconstruction algorithms and reconstruction filters

The noise power spectrum (NPS) is the reference metric for understanding the noise content in computed tomography (CT) images. To evaluate the noise properties of clinical multidetector (MDCT) scanners, local 2D and 3D NPSs were computed for different acquisition reconstruction parameters.A 64- and a 128-MDCT scanners were employed. Measurements were performed on a water phantom in axial and helical acquisition modes. CT dose index was identical for both installations. Influence of parameters such as the pitch, the reconstruction filter (soft, standard and bone) and the reconstruction algorithm (filtered-back projection (FBP), adaptive statistical iterative reconstruction (ASIR)) were investigated. Images were also reconstructed in the coronal plane using a reformat process. Then 2D and 3D NPS methods were computed.In axial acquisition mode, the 2D axial NPS showed an important magnitude variation as a function of the z-direction when measured at the phantom center. In helical mode, a directional dependency with lobular shape was observed while the magnitude of the NPS was kept constant. Important effects of the reconstruction filter, pitch and reconstruction algorithm were observed on 3D NPS results for both MDCTs. With ASIR, a reduction of the NPS magnitude and a shift of the NPS peak to the low frequency range were visible. 2D coronal NPS obtained from the reformat images was impacted by the interpolation when compared to 2D coronal NPS obtained from 3D measurements.The noise properties of volume measured in last generation MDCTs was studied using local 3D NPS metric. However, impact of the non-stationarity noise effect may need further investigations.

Report on Fly Ash as a Soil Additive, MLR-81-03, 1981

The addition of a selected self-cementing, Class C fly ash to blow sand soils improves their compacted strength greatly as opposed to the minimal strength improvement when fly ash is mixed with loess soil. By varying the percentage of fly ash added, the resulting blow sand-fly ash mixture can function as a low strength stabilized material or as a higher strength sub-base. Low strength stabilized material can also be obtained by mixing loess soils with a selected Class C fly ash. The development of the higher strength values required for subbase materials is very dependent upon compaction delay time and moisture condition of the material. Results at this time indicate that, when compaction delays are involved, excess moisture in the material has the greatest positive effect in achieving minimum strengths. Other added retarding agents, such as borax and gypsum, have less effect.

Health consultation : Exposure to fluff material from the Shine Brothers and noise concerns -- Spencer, Iowa (2011)

This letter has been prepared as a consultation to determine some potential health concerns raised by a resident of Spencer from exposure to wire shredder fluff material emitted by Shine Brothers metal salvaging facility in Spencer, Iowa on July 10, 2011 and, a concern regarding the health impacts from the level of noise measured by a resident near the metal salvaging facility.

Sidebranching induced by external noise in solutal dendritic growth

We have studied sidebranching induced by fluctuations in dendritic growth. The amplitude of sidebranching induced by internal (equilibrium) concentration fluctuations in the case of solidification with solutal diffusion is computed. This amplitude turns out to be significantly smaller than values reported in previous experiments. The effects of other possible sources of fluctuations (of an external origin) are examined by introducing nonconserved noise in a phase-field model. This reproduces the characteristics of sidebranching found in experiments. Results also show that sidebranching induced by external noise is qualitatively similar to that of internal noise, and it is only distinguished by its amplitude.

Asymmetric stochastic switching driven by intrinsic molecular noise

Low-copy-number molecules are involved in many functions in cells. The intrinsic fluctuations of these numbers can enable stochastic switching between multiple steady states, inducing phenotypic variability. Herein we present a theoretical and computational study based on Master Equations and Fokker-Planck and Langevin descriptions of stochastic switching for a genetic circuit of autoactivation. We show that in this circuit the intrinsic fluctuations arising from low-copy numbers, which are inherently state-dependent, drive asymmetric switching. These theoretical results are consistent with experimental data that have been reported for the bistable system of the gallactose signaling network in yeast. Our study unravels that intrinsic fluctuations, while not required to describe bistability, are fundamental to understand stochastic switching and the dynamical relative stability of multiple states.

Comparison and validation of tissue modelization and statistical classification methods in T1-weighted MR brain images.

This paper presents a validation study on statistical nonsupervised brain tissue classification techniques in magnetic resonance (MR) images. Several image models assuming different hypotheses regarding the intensity distribution model, the spatial model and the number of classes are assessed. The methods are tested on simulated data for which the classification ground truth is known. Different noise and intensity nonuniformities are added to simulate real imaging conditions. No enhancement of the image quality is considered either before or during the classification process. This way, the accuracy of the methods and their robustness against image artifacts are tested. Classification is also performed on real data where a quantitative validation compares the methods' results with an estimated ground truth from manual segmentations by experts. Validity of the various classification methods in the labeling of the image as well as in the tissue volume is estimated with different local and global measures. Results demonstrate that methods relying on both intensity and spatial information are more robust to noise and field inhomogeneities. We also demonstrate that partial volume is not perfectly modeled, even though methods that account for mixture classes outperform methods that only consider pure Gaussian classes. Finally, we show that simulated data results can also be extended to real data.

Effect of a Noise Wall on Snow Accumulation and Air Quality, 1985

A noise wall was investigated to assess its effect on snow accumulation and air quality. Wind tunnel studies were undertaken to evaluate (a) possible snow accumulations and (b) the dispersion of particulate concentrations (dust, smoke, and lead particles) and carbon monoxide. Full-scale monitoring of particulate concentrations and carbon monoxide was performed both before and after the noise wall was constructed. The wind tunnel experiments for snow accumulation were conducted on a model wall located in a flat, unobstructed area. A separated flow zone existed upwind of the wall and snow immediately began to accumulate over most of the separated zone. Having the noise wall in an aerodynamically rough area, such as in an urban area as this one was, substantially decreased the amount of snow collected, compared with in the wind tunnel studies, because of turbulence reducing the separation zone. The snow accumulation has not been significantly greater with the noise wall in place than it was before construction and has proven to be of no concern to date. Monitoring for particulate concentrations has shown that the noise wall has had a beneficial effect because the amount of material collected was reduced. With the noise wall in place, monitoring for carbon monoxide has indicated that (a) for equivalent emissions under conditions of high atmospheric stability and low wind speeds, the carbon monoxide levels would be lower; and (b) under conditions of low atmospheric stability and high wind speeds, the carbon monoxide levels would be higher than expected without the wall in place.

Piperine as a phytogenic additive in broiler diets

The objective of this work was to determine the effect of piperine as a phytogenic additive in chicken broiler diet. Seven‑day‑old male chicks were randomly allocated in four experimental treatments (n = 24), with four replicates (n = 6). The piperine was added to diets at concentrations of 0, 60, 120, and 180 mg kg‑1 for 35 consecutive days. The following were evaluated: biochemical, hematological and histopathological parameters; performance and carcass yield. Histomorphometric analyses were also carried out. The addition of 120 and 180 mg kg‑1 of piperine did not alter broiler body weight and feed conversion, whereas 60 mg kg‑1 of piperine interfered positively in both parameters from 36 to 42 days of age and significantly increased the absorption surface of the duodenum and the ileum. No macroscopic alteration in organ size and color was observed in the broilers fed diets with the evaluated concentrations of piperine. The supplementation of 120 and 180 mg kg‑1 of piperine is toxic to liver tissue and reduces the absorption surface of the jejune. The diet supplemented with 60 mg kg‑1 of piperine is safe.

Degree of multicollinearity and variables involved in linear dependence in additive-dominant models

The objective of this work was to assess the degree of multicollinearity and to identify the variables involved in linear dependence relations in additive-dominant models. Data of birth weight (n=141,567), yearling weight (n=58,124), and scrotal circumference (n=20,371) of Montana Tropical composite cattle were used. Diagnosis of multicollinearity was based on the variance inflation factor (VIF) and on the evaluation of the condition indexes and eigenvalues from the correlation matrix among explanatory variables. The first model studied (RM) included the fixed effect of dam age class at calving and the covariates associated to the direct and maternal additive and non-additive effects. The second model (R) included all the effects of the RM model except the maternal additive effects. Multicollinearity was detected in both models for all traits considered, with VIF values of 1.03 - 70.20 for RM and 1.03 - 60.70 for R. Collinearity increased with the increase of variables in the model and the decrease in the number of observations, and it was classified as weak, with condition index values between 10.00 and 26.77. In general, the variables associated with additive and non-additive effects were involved in multicollinearity, partially due to the natural connection between these covariables as fractions of the biological types in breed composition.

High capacity audio watermarking using the high frequency band of the wavelet domain

This paper proposes a novel high capacity robust audio watermarking algorithm by using the high frequency band of the wavelet decomposition at which the human auditory system (HAS) is not very sensitive to alteration. The main idea is to divide the high frequency band into frames and, for embedding, to change the wavelet samples depending on the average of relevant frame¿s samples. The experimental results show that the method has a very high capacity (about 11,000 bps), without significant perceptual distortion (ODG in [¿1 ,0] and SNR about 30dB), and provides robustness against common audio signal processing such as additive noise, filtering, echo and MPEG compression (MP3).

On the thermal noise introduced by a resistor in a circuit

Comentari sobre l'article publicat anteriorment pels mateixos autors: Vargas, M; Pallás, R; The seemingly paradoxical noise behaviour some active circuits. IEEE Transactions on Instrumentation and Measurement. 1994, vol. 43, núm. 5, p. 764-767

Comments on "On resistor-induced thermal noise in linear circuits"

Correspondència referida a l'article de R. Giannetti, publicat ibid. vol.49 p.87-88