scholarly journals A dual-tube sampling technique for snowpack studies

2020 ◽  
pp. 1-7
Author(s):  
Remi Dallmayr ◽  
Johannes Freitag ◽  
Maria Hörhold ◽  
Thomas Laepple ◽  
Johannes Lemburg ◽  
...  
Keyword(s):  
High Efficiency ◽  
Signal To Noise Ratio ◽  
Spatial Scales ◽  
Sampling Technique ◽  
Depth Resolution ◽  
Core Sample ◽  
Surface Sampling ◽  
Snow Properties ◽  
Spatial Noise ◽  
Level Of Understanding

Abstract The validity of any glaciological paleo proxy used to interpret climate records is based on the level of understanding of their transfer from the atmosphere into the ice sheet and their recording in the snowpack. Large spatial noise in snow properties is observed, as the wind constantly redistributes the deposited snow at the surface routed by the local topography. To increase the signal-to-noise ratio and getting a representative estimate of snow properties with respect to the high spatial variability, a large number of snow profiles is needed. However, the classical way of obtaining profiles via snow-pits is time and energy-consuming, and thus unfavourable for large surface sampling programs. In response, we present a dual-tube technique to sample the upper metre of the snowpack at a variable depth resolution with high efficiency. The developed device is robust and avoids contact with the samples by exhibiting two tubes attached alongside each other in order to (1) contain the snow core sample and (2) to access the bottom of the sample, respectively. We demonstrate the performance of the technique through two case studies in East Antarctica where we analysed the variability of water isotopes at a 100 m and 5 km spatial scales.

scholarly journals A dual-tube sampling technique for snowpack studies

2021 ◽  
Author(s):  
Remi Dallmayr ◽  
Johannes Freitag ◽  
Maria Hörhold ◽  
Thomas Laepple ◽  
Johannes Lemburg ◽  
...  
Keyword(s):  
High Efficiency ◽  
Signal To Noise Ratio ◽  
Spatial Scales ◽  
Sampling Technique ◽  
Depth Resolution ◽  
Core Sample ◽  
Surface Sampling ◽  
Snow Properties ◽  
Spatial Noise ◽  
Level Of Understanding

<p>The validity of any glaciological paleo proxy used to interpret climate records is based on the level of understanding of their transfer from the atmosphere into the ice sheet and their recording in the snowpack. Large spatial noise in snow properties is observed, as the wind constantly redistributes the deposited snow at the surface routed by the local topography. To increase the signal-to-noise ratio and getting a representative estimate of snow properties with respect to the high spatial variability, a large number of snow profiles is needed. However, the classical way of obtaining profiles via snow-pits is time and energy-consuming, and thus unfavourable for large surface sampling programs. In response, we present a dual-tube technique to sample the upper metre of the snowpack at a variable depth resolution with high efficiency. The developed device is robust and avoids contact with the samples by exhibiting two tubes attached alongside each other in order to (1) contain the snow core sample and (2) to access the bottom of the sample, respectively. We demonstrate the performance of the technique through two case studies in East Antarctica where we analysed the variability of water isotopes at a 100 m and 5 km spatial scales.</p>

Awareness on Corporate Social Responsibilty among the Consumers of Aluva Taluk

2018 ◽  
Vol 7 (5) ◽  
pp. 33
Author(s):  
Neeraja Unni ◽  
M Malarkodi
Keyword(s):  
Sampling Technique ◽  
Decision Making Process ◽  
Corporate World ◽  
Strategic Plans ◽  
Medium Level ◽  
Convenience Sampling ◽  
Level Of Understanding ◽  
Corporate Social ◽  
Social Responsibilty ◽  
Mandatory Provision

In today’s corporate world, the concept of Corporate Social Responsibility has been integrated into their strategic plans and policies. It has been incorporated into the decision making process taken in view of the competitive advantage that could be achieved through social initiatives. As consumers were the most sensitive group among the stakeholders to such initiatives, this paper tries to explore the awareness of consumers of companies towards CSR practices in AluvaTaluk. The paper also tries to examine whether CSR initiatives have any association with the consumers demographic profile. A total of 160 respondents were chosen from AluvaTaluk using convenience sampling technique. The data was collected through self-administered questionnaires and were analysed using SPSS 16.0 software. The study revealed that majority of the consumers of Aluva were aware of CSR but was unaware of the fact that it was a mandatory provision for the firms under the Companies Act, 2013. The consumers who were aware had only a medium level of understanding on the concept of CSR. Age, education and income of the consumers were found to have a significant association with their awareness on CSR.

Low-frequency multiplex CARS microscopy with a high-repetition near-infrared supercontinuum laser

2021 ◽  
Author(s):  
Yusuke Arashida ◽  
Atsushi Taninaka ◽  
Takayuki Ochiai ◽  
Hiroyuki Mogi ◽  
Shoji YOSHIDA ◽  
...  
Keyword(s):  
Near Infrared ◽  
High Efficiency ◽  
Signal To Noise Ratio ◽  
Low Frequency ◽  
High Sensitivity ◽  
High Repetition ◽  
Spectrum Shaping ◽  
Crystal Phase Transition ◽  
Wavenumber Region ◽  
Anti Stokes

Abstract We have developed a multiplex Coherent anti-Stokes Raman scattering (CARS) microscope effective for low-wavenumber measurement by combining a high-repetition supercontinuum light source of 1064 nm and an infrared high-sensitivity InGaAs diode array. This system could observe the low-wavenumber region down to 55 cm-1 with high sensitivity. In addition, using spectrum shaping and spectrum modulation techniques, we simultaneously realized a wide bandwidth (<1800 cm-1), high wavenumber resolution (9 cm-1), high efficiency, and increasing signal to noise ratio by reducing the effect of the background shape in low-wavenumber region. Spatial variation of a sulfur crystal phase transition with metastable states was visualized.

Characteristics of Immersion Sampling Technique in Confocal Raman Depth Profiling

2002 ◽  
Vol 56 (6) ◽  
pp. 776-782 ◽  
Author(s):  
J. Vyörykkä ◽  
M. Halttunen ◽  
H. Iitti ◽  
J. Tenhunen ◽  
T. Vuorinen ◽  
...  
Keyword(s):  
Light Scattering ◽  
Depth Profiling ◽  
Sampling Technique ◽  
Depth Resolution ◽  
Cover Glass ◽  
Actual Measurement ◽  
Fluid Layers ◽  
Immersion Technique ◽  
Confocal Raman ◽  
Measurement Depth

The confocal Raman technique is widely used for the depth profiling of thin transparent polymer films. Reported depth resolutions are on the order of two micrometers. The depth resolution is worsened and the actual measurement depth is changed by the use of metallurgical “dry” objectives. Also, if the sample is strongly light scattering, the measurement depth is reduced drastically. In this work, we demonstrate how these problems can be circumvented by using an immersion technique in confocal Raman depth profiling. In the method, two different immersion fluid layers and a cover glass, which separates the two fluid layers, are used. This configuration allows the fluid that is in contact with the sample to be selected with respect to the requirements dictated by the refractive index of the sample, sample–immersion fluid interaction, Raman spectra overlapping, or fluorescence quenching properties. The use of the immersion technique results in major improvements in the depth resolution and in the depth profiling capability of the confocal Raman technique when applied to strongly light scattering materials.

scholarly journals Assessment of the Impacts of Image Signal-to-Noise Ratios in Impervious Surface Mapping

2019 ◽  
Vol 11 (22) ◽  
pp. 2603
Author(s):  
George Xian ◽  
Hua Shi ◽  
Cody Anderson ◽  
Zhuoting Wu
Keyword(s):  
Spatial Resolution ◽  
Signal To Noise Ratio ◽  
Spatial Scales ◽  
Regression Tree ◽  
Remote Sensing Data ◽  
Impervious Surface ◽  
Landsat 8 ◽  
Signal To Noise ◽  
Study Results ◽  
The Impact

Medium spatial resolution satellite images are frequently used to characterize thematic land cover and a continuous field at both regional and global scales. However, high spatial resolution remote sensing data can provide details in landscape structures, especially in the urban environment. With upgrades to spatial resolution and spectral coverage for many satellite sensors, the impact of the signal-to-noise ratio (SNR) in characterizing a landscape with highly heterogeneous features at the sub-pixel level is still uncertain. This study used WorldView-3 (WV3) images as a basis to evaluate the impacts of SNR on mapping a fractional developed impervious surface area (ISA). The point spread function (PSF) from the Landsat 8 Operational Land Imager (OLI) was used to resample the WV3 images to three different resolutions: 10 m, 20 m, and 30 m. Noise was then added to the resampled WV3 images to simulate different fractional levels of OLI SNRs. Furthermore, regression tree algorithms were incorporated into these images to estimate the ISA at different spatial scales. The study results showed that the total areal estimate could be improved by about 1% and 0.4% at 10-m spatial resolutions in our two study areas when the SNR changes from half to twice that of the Landsat OLI SNR level. Such improvement is more obvious in the high imperviousness ranges. The root-mean-square-error of ISA estimates using images that have twice and two-thirds the SNRs of OLI varied consistently from high to low when spatial resolutions changed from 10 m to 20 m. The increase of SNR, however, did not improve the overall performance of ISA estimates at 30 m.

scholarly journals KEPATUHAN HUKUM IBU TERHADAP KETENTUAN PIDANA TERKAIT PERBUATAN YANG MENGAKIBATKAN PENDERITAAN PSIKIS ANAK

2018 ◽  
Vol 4 (2) ◽  
pp. 442-469
Author(s):  
Tisa Windayani
Keyword(s):  
Domestic Violence ◽  
Significant Role ◽  
Personal Values ◽  
Sampling Technique ◽  
Primary Data ◽  
Legal Compliance ◽  
Good Relationship ◽  
Purposive Sampling ◽  
Level Of Understanding ◽  
Penal Sanction

Art 80 and Art 76C  of Law No. 35/2014 purports to protect children from domestic violence (including most importantly those committed by the mother of the child).  This article using empirical juridical purports to analyze what factors are influential in determining compliance.  Primary data is collected using purposive sampling technique and subsequently is analyzed qualitatively.  The main result of the research is that avoidance of penal sanction is not a significant role in determining legal compliance.  More significant or influential are factors such as the extent or level of understanding the rule’s purpose or values behind the existing rule (prohibiting domestic violence), the need to maintain good relationship with the child; identification of the mother with certain groups in society and personal values. 

Material characterisation by enhanced resolution in non-stationary thermal wave imaging

2021 ◽  
Vol 63 (12) ◽  
pp. 721-726
Author(s):  
G T Vesala ◽  
V S Ghali ◽  
S Subhani ◽  
Y Naga Prasanthi
Keyword(s):  
Defect Detection ◽  
Thermal Wave ◽  
Signal To Noise Ratio ◽  
Empirical Relationship ◽  
Depth Resolution ◽  
Steel Sample ◽  
Detection Depth ◽  
Wave Imaging ◽  
Domain Phase ◽  
Thermal Wave Imaging

In the recent past, quadratic frequency-modulated thermal wave imaging (QFMTWI) has been advanced with a chirp z-transform (CZT)-based processing approach to facilitate enhanced subsurface anomaly detection, depth quantification and material property estimation with enhanced depth resolution. In the present study, the applicability of CZT-based phase analysis for foreign object defect detection in a structural steel sample using QFMTWI is validated through finite element-based numerical modelling rather than experimental verification due to limited available resources. Furthermore, the enhanced defect detection capability of the CZT phase approach is qualitatively compared with the frequency- and time-domain phase approaches using the defect signal-to-noise ratio (SNR) as a quality metric. Also, an empirical relationship between the observed phases and the thermal reflection coefficient is obtained, which recommends the CZT phase as a prominent approach for foreign material defect detection.

Knowledge and Anxiety Level on Labour Process among Primigravida Mothers in a Selected Hospital, Kamrup (M), Guwahati, Assam: A Descriptive Study

2021 ◽  
Vol 11 (9) ◽  
pp. 164-171
Author(s):  
Lalchungnungi . ◽  
Rikynti Nongkynrih
Keyword(s):  
Sampling Technique ◽  
Demographic Variables ◽  
Indian Women ◽  
Labour Process ◽  
Adequate Knowledge ◽  
Prenatal Counselling ◽  
Inadequate Knowledge ◽  
Moderate Negative Correlation ◽  
Level Of Understanding ◽  
Descriptive Survey

Introduction: Many Indian women are unaware about the changes that occur in their body during pregnancy and labour, as a result many mothers suffer physiologically and psychologically, hence education is needed for mother especially to primigravida mothers. Aims and Objectives: The aim of the study is to assess the level of knowledge and level of anxiety on labour process among primigravida mothers who are attending antenatal OPD at a selected hospital. Methods and materials: A descriptive survey research design was used and purposive sampling technique was used for obtaining sample for the study. Study was undertaken on 100 sample primigravida mothers at Maternity and Child welfare Hospital of Guwahati, Assam. Results: The finding shows that majority i.e. 53% had inadequate knowledge, 44% had moderately adequate knowledge and only three (3%) had adequate knowledge on labour process ,majority of the respondents i.e 58% had moderate anxiety and 42% had severe anxiety.There was association between the knowledge level and selected demographic variables such as age ,education, trimester of pregnancy and any prenatal counselling given. Also with anxiety and selected demographic variables such as education, occupation and any types of prenatal counseling attend. There was moderate negative correlation (-0.310) between knowledge and anxiety scores on labour process among primi gravida mothers. Conclusion: This study shows that primigravida mothers had lack of knowledge and moderate anxiety on labour process. Therefore health personnel need to conduct the education programmes to improve the level of understanding as to reduce the level of anxiety on labour process. Key words: Primigravida, labour process, anxiety, delivery, childbirth, pregnancy.

scholarly journals Short-Term Prediction of Bus Passenger Flow Based on a Hybrid Optimized LSTM Network

2019 ◽  
Vol 8 (9) ◽  
pp. 366 ◽  
Author(s):  
Yong Han ◽  
Cheng Wang ◽  
Yibin Ren ◽  
Shukang Wang ◽  
Huangcheng Zheng ◽  
...  
Keyword(s):  
High Efficiency ◽  
Short Term Memory ◽  
Spatial Scales ◽  
Optimization Procedure ◽  
Stochastic Gradient Descent ◽  
Short Term ◽  
Passenger Flow ◽  
Proposed Model ◽  
Gradient Descent Algorithm ◽  
Lstm Network

The accurate prediction of bus passenger flow is the key to public transport management and the smart city. A long short-term memory network, a deep learning method for modeling sequences, is an efficient way to capture the time dependency of passenger flow. In recent years, an increasing number of researchers have sought to apply the LSTM model to passenger flow prediction. However, few of them pay attention to the optimization procedure during model training. In this article, we propose a hybrid, optimized LSTM network based on Nesterov accelerated adaptive moment estimation (Nadam) and the stochastic gradient descent algorithm (SGD). This method trains the model with high efficiency and accuracy, solving the problems of inefficient training and misconvergence that exist in complex models. We employ a hybrid optimized LSTM network to predict the actual passenger flow in Qingdao, China and compare the prediction results with those obtained by non-hybrid LSTM models and conventional methods. In particular, the proposed model brings about a 4%–20% extra performance improvements compared with those of non-hybrid LSTM models. We have also tried combinations of other optimization algorithms and applications in different models, finding that optimizing LSTM by switching Nadam to SGD is the best choice. The sensitivity of the model to its parameters is also explored, which provides guidance for applying this model to bus passenger flow data modelling. The good performance of the proposed model in different temporal and spatial scales shows that it is more robust and effective, which can provide insightful support and guidance for dynamic bus scheduling and regional coordination scheduling.

scholarly journals An ILM-cosine transform-based improved approach to image encryption

2020 ◽  
Author(s):  
Mohit Dua ◽  
Arun Suthar ◽  
Arpit Garg ◽  
Vaibhav Garg
Keyword(s):  
Image Encryption ◽  
High Efficiency ◽  
Initial Conditions ◽  
Signal To Noise Ratio ◽  
Logistic Map ◽  
Random Order ◽  
Chaotic Sequence ◽  
Dynamical Behaviour ◽  
Original Position ◽  
Digital Information

Abstract The chaos-based cryptography techniques are used widely to protect digital information from intruders. The chaotic systems have some of special features that make them suitable for the purpose of encryption. These systems are highly unpredictable and are highly sensitive or responsive to the initial conditions, also known as butterfly effect. This sensitive dependence on initial conditions make these systems to exhibit an intricate dynamical behaviour. However, this dynamical behaviour is not much complex in simple one-dimensional chaotic maps. Hence, it becomes easy for an intruder to predict the contents of the message being sent. The proposed work in this paper introduces an improved method for encrypting images, which uses cosine transformation of 3-D Intertwining Logistic Map (ILM). The proposed approach has been split into three major parts. In the first part, Secure Hash Function-256 (SHA-256) is used with cosine transformed ILM (CT-ILM) to generate the chaotic sequence. This chaotic sequence is used by high-efficiency scrambling to reduce the correlations between the adjacent pixels of the image. In the second part, the image is rotated to move all the pixels away from their original position. In the third part, random order substitution is applied to change the value of image pixels. The effectiveness of the proposed method has been tested on a number of standard parameters such as correlation coefficient, Entropy and Unified average change in intensity. The proposed approach has also been tested for decryption parameters like mean square error and peak signal to noise ratio. It can easily be observed from the obtained results that the proposed method of image encryption is more secure and time efficient than some earlier proposed techniques. The approach works for both color and grey scale images.

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