Оценка влияния эксплуатации реактора БН-800 на содержание радионуклидов в местных продуктах питания района Белоярской АЭС

The research results are presented as an analysis of long-term data on the effect of gas-aerosol emissions and liquid discharges of Beloyarsk NPP and the Institute of Reactor Materials on the content of artificial radionuclides in local foodstuffs. It was noted that the distance and directions from radiation-hazardous facilities do not significantly affect the accumulation of 90Sr and 137Cs in potatoes and milk. The investigation of a wide range of foodstuffs from the private households of 23 settlements, forests, rivers, and a reservoir of the 30-km zone of the Beloyarsk NPP influence showed that the operation of the BN-800 reactor since 2016 did not lead to a registered increase in the content of artificial radionuclides in agricultural and natural foodstuffs. The maximum specific activities of 90Sr (0.84 Bq/kg) and 137Cs (0.26 Bq/kg) in root vegetables, potatoes, melons and vegetables were noted before the start of operation of the new power unit and were 45 and 300 times, respectively, lower than the current SanPiN standards. The highest content of 90Sr in milk (0.41 Bq/l) was 60 times lower than the requirements of SanPiN, 137Cs (0.11 Bq/l) was 900 times less than the permissible levels. In poultry, the specific activity of 90Sr (0.2-0.3 Bq/kg) and 137Cs (0.13-0.16 Bq/kg) has remained stable low in recent years, and the standardised content of 137Cs in beef (maximum 0.12 Bq/kg) more than 1.5 thousand times lower than the requirements of SanPiN. The highest concentration of 137Cs in wild berries, found in strawberries (1.27 Bq/kg), was 125 times less than SanPiN standards. The content of 90Sr in mushrooms was at the level of 0.1-2.5 Bq/kg, the content of 137Cs is slightly higher than - 0.6-5.8 Bq/kg. The maximum recorded specific activity of 137Cs in mushrooms was more than 80 times lower than the requirements of SanPiN. During the observation period, a decrease of up to 20% or more in the content of artificial radionuclides in samples of 5 fish species was noted; the maximum levels of 90Sr and 137Cs in it were 14 times lower than the strictest SanPiN standards (using fish for baby food). Selective radiation monitoring of foodstuffs of Beloyarsk NPP area aimed at 3H and 14C showed that the content of these radionuclides in foodstuffs was low, close to the background level. In agricultural products, 3H and 14C accumulated to a greater extent in potatoes and milk, and in natural products – in rough boletus and bream. There was noted a need to continue research on the accumulation of 3H and 14C in foodstuffs of Beloyarsk NPP vicinity.В работе представлен анализ многолетних данных по влиянию газоаэрозольных выбросов и жидких сбросов Белоярской АЭС и Института реакторных материалов на содержание техногенных радионуклидов в местных пищевых продуктах. Отмечено, что расстояние и направления от радиационно опасных объектов значимо не влияют на накопление 90Sr и 137Cs в картофеле и молоке. На примере широкого ряда продуктов питания из частного сектора 23 населенных пунктов, лесов, рек и водохранилища 30-километрвой зоны влияния Белоярской АЭС показано, что эксплуатация с 2016 г. реактора БН-800 не привела к регистрируемому увеличению содержания техногенных радионуклидов в сельскохозяйственной и природной пищевой продукции. Максимальные удельные активности 90Sr (0,84 Бк/кг) и 137Cs (0,26 Бк/кг) в корнеплодах, картофеле, бахчевых и овощах отмечались до начала эксплуатации нового энергоблока и были в 45 и 300 раз соответственно ниже действующих нормативов СанПиН. Наиболее высокое содержание в молоке 90Sr (0,41 Бк/л) было в 60 раз ниже требований СанПиН, 137Cs (0,11 Бк/л) в 900 раз меньше нормативов. В мясе домашней птицы удельная активность 90Sr (0,2–0,3 Бк/кг) и 137Cs (0,13–0,16 Бк/кг) в последние годы остается стабильно низкой, а нормируемое содержание 137Cs в говядине (максимально – 0,12 Бк/кг) более чем в 1,5 тыс. раз ниже требований СанПиН. Наиболее высокая концентрация 137Cs в лесных ягодах, обнаруженная в землянике (1,27 Бк/кг), меньше нормативов СанПиН в 125 раз. Содержание 90Sr в грибах находится на уровне 0,1–2,5 Бк/кг, 137Cs несколько выше – 0,6–5,8 Бк/кг. Максимально зафиксированная удельная активность 137Cs в грибах ниже требований СанПиН более чем в 80 раз. Отмечено уменьшение за период наблюдений до 20% и более содержания техногенных радионуклидов в пробах 5 видов рыб; максимальные уровни 90Sr и 137Cs в ней были ниже наиболее жестких нормативов СанПиН (использование рыбы для детского питания) в 14 раз. Выборочный радиационный контроль пищевых продуктов района Белоярской АЭС на 3H и 14C показал, что содержание этих радионуклидов в продуктах питания находится на низком, близком к фоновому уровне. В сельскохозяйственной продукции 3H и 14C в большей степени накапливаются в картофеле и молоке, из при- родных продуктов в подберезовике и леще. Отмечена необходимость продолжения исследований по изучению накопления 3H и 14C в продуктах питания района Белоярской АЭС

Assessment of the impact of the BN-800 reactor operation on the radionuclides content in local foodstuffs in the vicinity of Beloyarsk NPP

The research results are presented as an analysis of long-term data on the effect of gas-aerosol emissions and liquid discharges of Beloyarsk NPP and the Institute of Reactor Materials on the content of artificial radionuclides in local foodstuffs. It was noted that the distance and directions from radiation-hazardous facilities do not significantly affect the accumulation of 90Sr and 137Cs in potatoes and milk. The investigation of a wide range of foodstuffs from the private households of 23 settlements, forests, rivers, and a reservoir of the 30-km zone of the Beloyarsk NPP influence showed that the operation of the BN-800 reactor since 2016 did not lead to a registered increase in the content of artificial radionuclides in agricultural and natural foodstuffs. The maximum specific activities of 90Sr (0.84 Bq/kg) and 137Cs (0.26 Bq/kg) in root vegetables, potatoes, melons and vegetables were noted before the start of operation of the new power unit and were 45 and 300 times, respectively, lower than the current SanPiN standards. The highest content of 90Sr in milk (0.41 Bq/l) was 60 times lower than the requirements of SanPiN, 137Cs (0.11 Bq/l) was 900 times less than the permissible levels. In poultry, the specific activity of 90Sr (0.2-0.3 Bq/kg) and 137Cs (0.13-0.16 Bq/kg) has remained stable low in recent years, and the standardised content of 137Cs in beef (maximum 0.12 Bq/kg) more than 1.5 thousand times lower than the requirements of SanPiN. The highest concentration of 137Cs in wild berries, found in strawberries (1.27 Bq/kg), was 125 times less than SanPiN standards. The content of 90Sr in mushrooms was at the level of 0.1-2.5 Bq/kg, the content of 137Cs is slightly higher than - 0.6-5.8 Bq/kg. The maximum recorded specific activity of 137Cs in mushrooms was more than 80 times lower than the requirements of SanPiN. During the observation period, a decrease of up to 20% or more in the content of artificial radionuclides in samples of 5 fish species was noted; the maximum levels of 90Sr and 137Cs in it were 14 times lower than the strictest SanPiN standards (using fish for baby food). Selective radiation monitoring of foodstuffs of Beloyarsk NPP area aimed at 3H and 14C showed that the content of these radionuclides in foodstuffs was low, close to the background level. In agricultural products, 3H and 14C accumulated to a greater extent in potatoes and milk, and in natural products – in rough boletus and bream. There was noted a need to continue research on the accumulation of 3H and 14C in foodstuffs of Beloyarsk NPP vicinity

A multi-stage approach for fast person re-identification

One of the goals of person re-identification systems is to support video-surveillance operators and forensic investigators to find an individual of interest in videos taken by a network of non-overlapping cameras. This is attained by sorting images of previously observed individuals for decreasing values of their similarity with the query individual. Several appearance-based descriptors have been proposed so far, together with ad hoc similarity measures, mostly aimed at improving ranking quality. We address instead the issue of the processing time required to compute the similarity values, and propose a multi-stage ranking approach to attain a trade-off with ranking quality, for any given descriptor. We give a preliminary evaluation of our approach on the benchmark VIPeR data set, using different state-of-the-art descriptors