Review of overall parameters of giant radio pulses from the Crab pulsar and B1937+21

We present a review of observed parameters of giant radio pulses, based on the observations conducted by our group during recent years. The observations cover a broad frequency range of about 3 octaves, concentrating between 600 and 4850 MHz. Giant pulses of both the Crab pulsar and the millisecond pulsar B1937+21 were studied with the 70-m Tidbinbilla, the 100-m GBT, 64-m Kalyazin and Westerbork radio telescopes. We discuss pulse energy distribution, dependence of peak flux density from the pulse width, peculiarities of radio spectra, and polarization properties of giant radio pulses.Comment: 3 pages, 4 figures, to be published in the Proceedings of the conference "40 Years of Pulsars: Millisecond Pulsars, Magnetars, and More" held on August 12-17, 2007, McGill University, Montreal, Canad

A broadband radio study of the average profile and giant pulses from PSR B1821-24A

We present the results of wide-band (720-2400 MHz) study of PSR B1821-24A (J1824-2452A, M28A), an energetic millisecond pulsar visible in radio, X-rays and gamma-rays. In radio, the pulsar has a complex average profile which spans >85% of the spin period and exhibits strong evolution with observing frequency. For the first time we measure phase-resolved polarization properties and spectral indices of radio emission throughout almost all of the on-pulse window. We combine this knowledge with the high-energy information to compare M28A to other known gamma-ray millisecond pulsars and to speculate that M28A's radio emission originates in multiple regions within its magnetosphere (i.e. both in the slot or outer gaps near the light cylinder and at lower altitudes above the polar cap). M28A is one of the handful of pulsars which are known to emit Giant Pulses (GPs) -- short, bright radio pulses of unknown nature. We report a drop in the linear polarization of the average profile in both windows of GP generation and also a `W'-shaped absorption feature (resembling a double notch), partly overlapping with one of the GP windows. The GPs themselves have broadband spectra consisting of multiple patches with fractional spectral width ($\Delta\nu/\nu$) of about 0.07. Although our time resolution was not sufficient to resolve the GP structure on the microsecond scale, we argue that GPs from this pulsar most closely resemble the GPs from the main pulse of the Crab pulsar, which consist of a series of narrowband nanoshots.Comment: 16 pages, 8 figures, accepted to Ap

Mapping growing stock volume and forest live biomass: a case study of the Polissya region of Ukraine

Forest inventory and biomass mapping are important tasks that require inputs from multiple data sources. In this paper we implement two methods for the Ukrainian region of Polissya: random forest (RF) for tree species prediction and k-nearest neighbors (k-NN) for growing stock volume and biomass mapping. We examined the suitability of the five-band RapidEye satellite image to predict the distribution of six tree species. The accuracy of RF is quite high: ~99% for forest/non-forest mask and 89% for tree species prediction. Our results demonstrate that inclusion of elevation as a predictor variable in the RF model improved the performance of tree species classification. We evaluated different distance metrics for the k-NN method, including Euclidean or Mahalanobis distance, most similar neighbor (MSN), gradient nearest neighbor, and independent component analysis. The MSN with the four nearest neighbors (k = 4) is the most precise (according to the root-mean-square deviation) for predicting forest attributes across the study area. The k-NN method allowed us to estimate growing stock volume with an accuracy of 3 m3 ha−1 and for live biomass of about 2 t ha−1 over the study area

Correlation of Chandra photons with the radio giant pulses from the Crab pulsar

No apparent correlation was found between giant pulses (GPs) and X-ray photons from the Crab pulsar during 5.4 hours of simultaneous observations with the Green Bank Telescope at 1.5 GHz and Chandra X-Ray Observatory primarily in the energy range 1.5-4.5 keV. During the Crab pulsar periods with GPs the X-ray flux in radio emission phase windows does not change more than by +-10% for main pulse (MP) GPs and +-30% for interpulse (IP) GPs. During giant pulses themselves, the X-ray flux does not change more than by two times for MP GPs and 5 times for IP GPs. All limits quoted are compatible with 2-sigma fluctuations of the X-ray flux around the sets of false GPs with random arrival times. The results speak in favor of changes in plasma coherence as the origin of GPs. However, the results do not rule out variations in the rate of particle creation if the particles that emit coherent radio emission are mostly at the lowest Landau level.Comment: 7 pages, 5 figures; to appear in The Astrophysical Journal, 201

Pulsar Science with the Green Bank 43m Telescope

The 43m telescope at the NRAO site in Green Bank, WV has recently been outfitted with a clone of the Green Bank Ultimate Pulsar Processing Instrument (GUPPI \cite{Ransom:2009}) backend, making it very useful for a number of pulsar related studies in frequency ranges 800-1600 MHz and 220-440 MHz. Some of the recent science being done with it include: monitoring of the Crab pulsar, a blind search for transient sources, pulsar searches of targets of opportunity, and an all-sky mapping project. For the Crab monitoring project, regular observations are searched for giant pulses (GPs), which are then correlated with $\gamma$-ray photons from the \emph{Fermi} spacecraft. Data from the all-sky mapping project are first run through a pipeline that does a blind transient search, looking for single pulses over a DM range of 0-500 pc~cm$^{-3}$. These projects are made possible by MIT Lincoln Labs.Comment: 2 pages, 1 figure, to appear in AIP Conference Proceedings of Pulsar Conference 2010 "Radio Pulsars: a key to unlock the secrets of the Universe", Sardinia, October 201

Correlation of Fermi photons with high-frequency radio giant pulses from the Crab pulsar

To constrain the giant pulse (GP) emission mechanism and test the model of Lyutikov (2007) for GP emission, we have carried out a campaign of simultaneous observations of the Crab pulsar at gamma-ray (Fermi) and radio (Green Bank Telescope) wavelengths. Over 10 hours of simultaneous observations we obtained a sample of 2.1x10^4 giant pulses, observed at a radio frequency of 9 GHz, and 77 Fermi photons, with energies between 100 MeV and 5 GeV. The majority of GPs came from the interpulse (IP) phase window. We found no change in the GP generation rate within 10-120 s windows at lags of up to +-40 min of observed gamma-ray photons. The 95% upper limit for a gamma-ray flux enhancement in pulsed emission phase window around all GPs is 4 times the average pulsed gamma-ray flux from the Crab. For the subset of IP GPs, the enhancement upper limit, within the IP emission window, is 12 times the average pulsed gamma-ray flux. These results suggest that GPs, at least high-frequency IP GPs, are due to changes in coherence of radio emission rather than an overall increase in the magnetospheric particle density.Comment: 9 pages, 6 figures; to appear in The Astrophysical Journal, February 201

РЕЙТИНГОВА ОЦІНКА ДІЯЛЬНОСТІ СТРАХОВИХ КОМПАНІЙ В УКРАЇНІ ЗІ СТРАХУВАННЯ ЖИТТЯ

The article examines the essence of the process of rating assessment of life insurance companies as an instrument for identifying their finan cial reiability and stability in the insurance market. The approaches to the interpretation of "rating", "rating evaluation" and "valuation" are  described and summarized. The signs of the objective rating estimation of the estimation object are highlited. Rating assessments are very complex and ambiguous. In addition, there are various appro aches of the assessment of the performance of insurance companies. I nvestigated the regulatory framework for the implementation of ratin g assessment of insurers based on which is concludes that today Ukraine has a system of regulations that reinforce the status and rank ing order. The methodology for assessing the activity of the insurance company, approved by the Resolution of the State Commission for Regulation of Financial Services Markets of Ukraine No. 3755 "On Approval of Recommendations for the Analysis of Insurers Activities, "is provided. According to this methodology and to the data of 2017 were calculated indicators of early warning tests for selected insurance companies of life insurance of various corporate models: CHAO "Insurance company" PZU Ukraine life insurance"– foreign capital, CHAO IC" Blue Polis "a captive insurance company and CHAO "Insurance group TAS – life insurance" – domestic capital and developed rating on these data. The integral rating evaluation of eachcompany is determined by comparing of the calculated value with the scale of standard indicators in accordance to the methodology. It was concluded that the rating evaluates the relative financial security of insurers who have entered into an agreement with the insurer and is a convenient tool for differentiating the credit quality of insurance companies, also allows us to state that the domestic insurance market has demonstrated rather high rates of development, does not rank in the leading positions of the world insurance market and almost do not affect the results of its functioning.В статье исследована сущность процесса рейтинговой оценки страховых компаний по страхованию жизни, как инструмента выявления их финансовой надежности и устойчивости на страховом рынке. Охарактеризованы и обобщены подходы к определению понятия «рейтинг», «рейтинговая оценка» и «рейтингование». Выделены признаки объективной рейтинговой оценки объекта оценки. Рейтинговые оценки весьма сложные и неоднозначные. Кроме того, возможны различные подходы к оценке деятельности страховых компаний. С точки зрения это, возникает вопрос который для нас является наиболее пригодным. Исследована нормативно-правовая база по осуществлению рейтинговой оценки страховщиков на основе чего сделан вывод, что на сегодняшний день в Украине существует система нормативно-правовых актов, закрепляющих статус и порядок рейтингования. Приведена методика оценки деятельности страховой компании, утвержденной Распоряжением Государственной комиссии по регулированию рынков финансовых услуг Украины №3755 «Об утверждении Рекомендаций по анализу деятельности страховщиков». Согласно этой методике по данным 2017 рассчитаны показатели тестов раннего предупреждения для выбранных страховых компаний по страхованию жизни различных корпоративных моделей: «Страховая компания« PZU Украина страхование жизни» – иностранный капитал, СК «Голубой Полис» – кептивная страховая компания и «Страховая Группа « ТАСС – страхование жизни» – отечественный капитал и разработали рейтингование по этим данным. Интегральная рейтинговая оценка каждой компании определена путем сравнения рассчитанного значения со шкалой нормативных показателей по методике. Сделан вывод, что рейтинг оценивает относительную финансовую безопасность страхователей, заключивших договор со страховщиком, и является удобным инструментом для дифференциации кредитного качества страховых компаний, а также позволяют констатировать, что отечественный страховой рынок, демонстрируя достаточно высокие темпы развитии, не занимает ведущих позиций в рейтинге мирового страхового рынка и почти не влияют на результаты его функционирования. У статті досліджено сутність процесу рейтингової оцінки страхових компаній зі страхування життя, як інструменту виявлення їх фінансової надійності та стійкості на страховому ринку. Охарактеризовано та узагальнено підходи щодо визначення поняття «рейтинг», «рейтингова оцінка» та «рейтингування». Виділено ознаки об’єктивної рейтингової оцінки об’єкта оцінки. Рейтингові оцінки вельми складні і неоднозначні. Крім того, можливі різноманітні підходи до оцінки діяльності страхових компаній. З погляду на це, виникає питання який для нас є найбільш придатним Досліджено нормативно-правову базу щодо здійснення рейтингової оцінки страховиків на основі чого зроблено висновок, що на сьогоднішній день в Україні існує система нормативно-правових актів, що закріплюють статус та порядок рейтингування. Наведено методику оцінки діяльності страхової компанії, яка затверджена Розпорядженням Державної комісії з регулювання ринків фінансових послуг України № 3755 «Про затвердження Рекомендацій щодо аналізу діяльності страховиків». Відповідно до цієї методики за даними 2017 року розрахували показники тестів раннього попередження для обраних страхових компаній зі страхування життя різних корпоративних моделей: ПрАТ «Страхова компанія «PZU Україна страхування життя» – іноземний капітал, ПАТ СК «Блакитний Поліс» – кептивна страхова компанія та ПрАТ «Страхова Група «ТАС – страхування життя» – вітчизняний капітал та розробили рейтингування за цими даними. Інтегральна рейтингова оцінка кожної компанії визначена шляхом порівняння розрахованого значення із шкалою нормативних показників відповідно до методики. Зроблено висновок, що рейтинг оцінює відносну фінансову безпеку страхувальників, які уклали договір із страховиком, і є зручним інструментом для диференціації кредитної якості страхових компаній, а також дозволяють констатувати, що вітчизняний страховий ринок, демонструючи досить високі темпи розвитку, не посідають чільних позицій у рейтингу світового страхового ринку і майже не впливають на результати його функціонування

Tracking Rates of Forest Disturbance and Associated Carbon Loss in Areas of Illegal Amber Mining in Ukraine Using Landsat Time Series

Mapping forest disturbance is crucial for many applications related to decision-making for sustainable forest management. This study identified the effect of illegal amber mining on forest change and accumulated carbon stock across a study area of 8125.5 ha in northern Ukraine. Our method relies on the Google Earth Engine (GEE) implementation of the Landsat-based Detection of Trends in Disturbance and Recovery (LandTrendr) temporal segmentation algorithm of Landsat time-series (LTS) to derive yearly maps of forest disturbance and recovery in areas affected by amber extraction operations. We used virtual reality (VR) 360 interactive panoramic images taken from the sites to attribute four levels of forest disturbance associated with the delta normalized burn ratio (dNBR) and then calculated the carbon loss. We revealed that illegal amber extraction in Ukraine has been occurring since the middle of the 1990s, yielding 3260 ha of total disturbed area up to 2019. This study indicated that the area of forest disturbance increased dramatically during 2013–2014, and illegal amber operations persist. As a result, regrowth processes were mapped on only 375 ha of total disturbed area. The results were integrated into the Forest Stewardship Council® (FSC®) quality management system in the region to categorize Forest Management Units (FMUs) conforming to different disturbance rates and taking actions related to their certification status. Moreover, carbon loss evaluation allows the responsible forest management systems to be streamlined and to endorse ecosystem service assessment