scholarly journals Method for long-term coherent-noncoherent signal accumulation with non-zero higher derivatives range to radar target

Doklady BGUIR ◽  
2021 ◽  
Vol 19 (7) ◽  
pp. 89-98
Author(s):  
S. V. Kozlov ◽  
Van Cuong Le
Keyword(s):  
Radial Velocity ◽  
Method Of Moments ◽  
Simulation Modeling ◽  
Radar Target ◽  
Radial Acceleration ◽  
Coherent Accumulation ◽  
Higher Derivatives ◽  
Reflected Signal ◽  
Made In

A method of long-term combined accumulation of the reflected signal is justified, which provides for its division into disjoint subsets, coherent accumulation in subsets using one of the fast algorithms and subsequent incoherent accumulation of the squares of the modules of the results of processing the subsets. A distinctive method’s feature is the use with incoherent accumulation of maxima of the squares of the moduli of the coherent processing results, that are selected from the range / radial velocity regions in accordance with a given hypothesis about the minimum and maximum values of the target radial velocity and the radial acceleration detection channel setting.The efficiency of the method was confirmed by simulation modeling. Using the theories of ordinal statistics and the method of moments, a method for calculating the probability of correct detection is developed. Estimates of processing losses are made in comparison with coherent and incoherent accumulation algorithms for a signal reflected from a point target, for the case when there is no range and frequency migration. Estimates for the required number of receiver channels are given.

scholarly journals Model and long-term coherent accumulation basic algorithm for the reflected signal with non-zero higher derivative range to radar target

Doklady BGUIR ◽  
2021 ◽  
Vol 19 (2) ◽  
pp. 49-57
Author(s):  
S. V. Kozlov ◽  
Le Van Cuong
Keyword(s):  
Matched Filter ◽  
Radar Target ◽  
Complex Frequency ◽  
Repetition Period ◽  
Target Movement ◽  
Basic Algorithm ◽  
Coherent Accumulation ◽  
Phase Alignment ◽  
Reflected Signal

The purpose of the work was to substantiate a mathematical model of the signal reflected from moving radar target at the time of its observation, which determines the need to take into account the range migration and its derivatives up to the third order, inclusive, and the Doppler frequency migration, and the basic algorithm of long-term coherent accumulation for the reflected signal. The algorithm provides for the calculation of the “fast” spectra samples, within each repetition period, time, the phase alignment of the spectra samples by multiplying by the correcting phase factors determined by the expected parameters of the target movement and the number of the repetition period, the summation of the spectral samples in the “slow” time, the multiplication of the result by complex frequency response of a matched filter of a single signal and performing an inverse Fourier transform. The performance of the algorithm is illustrated by the results of computer simulation.

Research on Velocity Measurement of PD Radar Based on Non-Coherent Accumulation and Waveform Analysis

2014 ◽  
Vol 513-517 ◽  
pp. 2999-3002
Author(s):  
Xu Dong Zhang ◽  
Yun Neng Yuan ◽  
Jun Wang
Keyword(s):  
Radial Velocity ◽  
Target Tracking ◽  
Velocity Measurement ◽  
Measurement Accuracy ◽  
Waveform Analysis ◽  
Radar Target ◽  
Running Time ◽  
Coherent Accumulation ◽  
High Measurement ◽  
High Measurement Accuracy

According to the process of PD radar target tracking, the radial motion of target has a significant impact on velocity measurement. Simulation shows that there is an apparent relation between radial velocity and non-coherent accumulated waveform. Based on the calculation of the entropy of non-coherent accumulated waveform, a method based on waveform entropy in velocity measurement is proposed. Experiments show that the new method can achieve high measurement accuracy, and is insensitive to velocity. At the same time, a rough estimation of velocity is used to shorten the running time.

scholarly journals Long-time coherent accumulation algorithms for reflected signal with non-zero higher derivatives of the range to radar target in the spectral domain

Doklady BGUIR ◽  
2021 ◽  
Vol 19 (5) ◽  
pp. 35-44
Author(s):  
S. V. Kozlov ◽  
Van Cuong Le
Keyword(s):  
Fourier Transform ◽  
Matched Filter ◽  
Repetition Period ◽  
Coherent Accumulation ◽  
Uncertainty Function ◽  
Long Time ◽  
Higher Derivatives ◽  
Range Migration ◽  
The Difference

The purpose of the article is to present computationally economical algorithms for long-term coherent accumulation of signals reflected from a point target with compensation for range and frequency migration and accumulation of signals in the spectral region. The algorithms include intra-period processing with simultaneous correction of range and frequency migration and inter-period processing with coherent accumulation of signals at the output of intra-period processing. In the first variant of the algorithm, intra-period processing is implemented by calculating the spectra of the received signals in each repetition period, multiplying the samples of the spectra by the samples of the amplitude-phase-frequency characteristic of the matched filter of a single signal and correcting phase coefficients determined by the number of the repetition period and the values of the range derivatives, and the inverse Fourier transform of the transformed spectra. The difference between the second version of the algorithm at the stage of intraperiod processing is the correction of only the quadratic and subsequent components of the range and frequency migration and the use of the keystone transformation, which eliminates the linear range migration. Coherent accumulation for both variants is realized due to the fast Fourier transform of the signal samples over the repetition periods for all samples over the range. The concept of “rough speed resolutionˮ is introduced, which determines the arrangement of channels when compensating for range migration. The uncertainty function in the coordinates “velocity–acceleration” is obtained. The equivalence of the two variants of the algorithm is shown and estimates for the required number of receiver channels are given. The simulation results confirming the operability of the proposed algorithms are presented.

Soil and ecological division into districts of the Baikal region

2018 ◽  
Vol 940 (10) ◽  
pp. 54-64 ◽  
Author(s):  
I.A. Belozertseva ◽  
A.A. Sorokovoj
Keyword(s):  
Baikal Region ◽  
Soil Cover ◽  
Soil Formation ◽  
Forest Steppe ◽  
Leading Role ◽  
Soil Cover Structure ◽  
Reflecting Surface ◽  
Heat And Moisture ◽  
Made In

On the basis of long-term researches of soils in the territory of Russia and Mongolia soil and ecological division into districts of the Baikal region is carried out. At division into districts the whole set of an environment of soil formation was considered. On the map of soil and ecological division into districts 13 mountain, mid-mountain, low-mountain taiga, foothill, hollow-valley, forest-steppe and steppe provinces reflecting surface device originality as the ratio of balance of heat and moisture forming a basis to zoning is shown against the background of difficult orography are allocated. In total 42 districts on lithologic-geomorphological features are allocated. In formation of distinctions of a soil cover of these provinces the leading role is played by bioclimatic factors and inside them the lithologic-geomorphological ones. In the view of structural approach of the district they are considered as territories with a certain natural change of several types of the soil cover structure caused by features of a relief and the parent rock. The map is made in the MapInfo program. It is revealed that on ill-defined width zoning of soils the vertical one which has a greater influence on soils of this region is imposed. Soils of the Baikal region are not similar to the soils located at the same latitude of the flat European territory of Russia. Zone soils of this territory are specific and original.

scholarly journals Mechanical Properties of Cement-Treated Soil Mixed with Cellulose Nanofibre

2021 ◽  
Vol 11 (14) ◽  
pp. 6425
Author(s):  
Hidenori Takahashi ◽  
Shinya Omori ◽  
Hideyuki Asada ◽  
Hirofumi Fukawa ◽  
Yusuke Gotoh ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Flexural Strength ◽  
Geotechnical Engineering ◽  
Strength Development ◽  
Soft Ground ◽  
Wood Cellulose ◽  
Treated Soil ◽  
Made In ◽  
Cement Treatment

Cellulose nanofibre (CNF), a material composed of ultrafine fibres of wood cellulose fibrillated to nano-order level, is expected to be widely used because of its excellent properties. However, in the field of geotechnical engineering, almost no progress has been made in the development of techniques for using CNFs. The authors have focused on the use of CNF as an additive in cement treatment for soft ground, where cement is added to solidify the ground, because CNF can reduce the problems associated with cement-treated soil. This paper presents the results of a study on the method of mixing CNF, the strength and its variation obtained by adding CNF, and the change in permeability. CNF had the effect of mixing the cement evenly and reducing the variation in the strength of the treated soil. The CNF mixture increased the strength at the initial age but reduced the strength development in the long term. The addition of CNF also increased the flexural strength, although it hardly changed the permeability.

scholarly journals R Coronae Borealis Stars: Long-Term Photometric & Spectroscopic Studies

1998 ◽  
Vol 11 (1) ◽  
pp. 379-379
Author(s):  
P.L. Cottrell ◽  
L. Skuljan ◽  
P.M. Kilmartin ◽  
C. Gilmore ◽  
W.A. Lawson
Keyword(s):  
Radial Velocity ◽  
Spectroscopic Studies ◽  
Photometric Data ◽  
Decline Phase ◽  
Dust Clouds ◽  
Medium Resolution ◽  
Formation And Evolution ◽  
R Coronae Borealis Stars ◽  
Insight Into

For more than a decade we have been able to acquire and analyse a significant amount of photometric data of the highly variable R Coronae Borealis (RCB) stars. This has made been possible by a photometric service observing programme instigated at the Observatory. These photometric data have been combined with less extensive spectroscopic coverage, particularly of the decline phase of these stars. These have been supplemented by observations obtained at Mount Stromlo and Siding Spring Observatories for a radial velocity study. Significantly more spectroscopic observations are now being acquired with the development of a new medium resolution spectrograph at Mount John University Observatory. In this poster we will present recent photometric and spectroscopic results for a number of the RCB stars in our sample. This observational and analysis work can be used to provide further insight into the nature of these stars, their likely progeny and progenitors and the processes that are involved in the formation and evolution of the obscuring dust clouds which cause the decline phase.

No Justice Without Peace, But What Peace Is on Offer?

2020 ◽  
Author(s):  
Mark Kersten
Keyword(s):  
Middle East ◽  
International Criminal Court ◽  
International Criminal ◽  
Criminal Court ◽  
Term Stability ◽  
Long Term Stability ◽  
Peace Processes ◽  
Lasting Peace ◽  
Made In

Abstract Does the potential investigation into Palestine by the International Criminal Court (ICC) threaten the chances of a lasting ‘peace’ between Israel and Palestine? This article endeavours to answer that question and critically assesses claims that the Court could undermine peace in the Middle East. I first examine the key claims made in the so-called ‘peace versus justice’ debate. I then outline some of the specific arguments made in the context of a possible ICC investigation in Palestine that touch upon concerns over the Court’s impacts on peace processes and negotiations. Following this, I try to assess critically the validity of these claims, arguing that while it would be wrong to conclude that the ICC will invariably have positive impacts on efforts to establish peace, there is no evidence that the Court will undermine whatever ‘peace’ is currently on offer for Palestinians and Israelis. On the contrary, this ‘peace’ may itself be a threat to resolving the conflict peaceably and to long-term stability in the region. Finally, I conclude the article with some reflections on the peace-justice debate and its applicability to the Israel–Palestine situation.

scholarly journals Long-Term Coudé Radial-Velocity Studies With a 1.2-m Telescope

2001 ◽  
Vol 183 ◽  
pp. 283-288
Author(s):  
C.D. Scarfe
Keyword(s):  
Radial Velocity ◽  
Binary Stars ◽  
Star System ◽  
Standard Star ◽  
Stellar Spectra ◽  
Multiple Stars ◽  
Binary And Multiple Stars ◽  
Selection Of

AbstractI have used the 1.2-m telescope and coudé spectrograph of the Dominion Astrophysical Observatory for more than 30 years in a program of radial-velocity observations of binary stars. The program was begun with photographic plates as detectors, but for 20 years the primary detector has been the radial-velocity scanner, which cross-correlates stellar spectra with an artificial mask.Since some of the binaries under observation have periods of several years, the instrument’s stability is an important consideration. I have therefore been obliged to observe standard stars and asteroids to check its performance. These observations are of relevance to efforts to improve the IAU standard star system.I will describe the telescope, spectrograph and scanner, and will briefly discuss some of the results obtained for a selection of binary and multiple stars.

Commentary: The Broader Context of Long-Term Care Ethics

2016 ◽  
Vol 25 (3) ◽  
pp. 554-556
Author(s):  
Jason Lesandrini ◽  
Carol O’Connell
Keyword(s):  
Care Setting ◽  
Long Term Care ◽  
Ethical Issues ◽  
Term Care ◽  
Ethical Concerns ◽  
Healthcare Settings ◽  
Care Facilities ◽  
Ethics Program ◽  
Made In

Ethical issues in long-term care settings, although having received attention in the literature, have not in our opinion received the appropriate level they require. Thus, we applaud the Cambridge Quarterly for publishing this case. We can attest to the significance of ethical issues arising in long-term care facilities, as Mr. Hope’s case is all too familiar to those practicing in these settings. What is unique about this case is that an actual ethics consult was made in a long-term care setting. We have seen very little in the published literature on the use of ethics structures in long-term care populations. Our experience is that these healthcare settings are ripe for ethical concerns and that providers, patients, families, and staff need/desire ethics resources to actively and preventively address ethical concerns. The popular press has begun to recognize the ethical issues involved in long-term care settings and the need for ethics structures. Recently, in California a nurse refused to initiate CPR for an elderly patient in a senior residence. In that case, the nurse was quoted as saying that the facility had a policy that nurses were not to start CPR for elderly patients.1 Although this case is not exactly the same as that of Mr. Hope, it highlights the need for developing robust ethics program infrastructures in long-term care settings that work toward addressing ethical issues through policy, education, and active consultation.

Will Strategy Prevail over Economics? An Analysis of Charanka Solar Park in Gujarat

2016 ◽  
Vol 5 (2) ◽  
pp. 162-167
Author(s):  
Saif Siddiqui ◽  
Sumaira Jan
Keyword(s):  
Solar Energy ◽  
Solar Power ◽  
Power Production ◽  
Energy Crisis ◽  
Energy Sources ◽  
Potential Source ◽  
The World ◽  
Made In

The Charanka Solar Park, one of the world’s largest multi-developer and multi-beneficiary solar parks, is the hub of solar power production in India. It contributes about 6 per cent to the total solar power production in the country. Although solar power is more expensive than the traditional power in the country, its sheen is still not high to make it a potential source to eliminate energy crisis not just in India but all across the world. Researchers are continuously pushing their envelope to explore as to why solar energy should be adopted over traditional energy sources irrespective of the fact that it is more expensive. The war between its financial and strategic viability is going on. Efforts are being made in the direction of reducing its costs and making it as a financially viable and strategically active option. This case is an attempt in the same direction. We are using Charanka Solar Park as a base to explore if there is any future for such projects in the country. There are projects which are no doubt operational but their long-term viability is truly questionable.

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