Comprehensive assessment and variation characteristics of the drought intensity in North China based on EID

Under the new background of climate change, it is very important to identify the characteristics of drought in North China. Based on the daily Meteorological Drought Comprehensive Index from 494 national meteorological stations in North China during 1961–2019, the drought processes and their intensity are identified by applying the ‘extreme’ intensity-duration theory. Then, the stage variation characteristics of the drought trend, the average drought intensity and the drought frequency are analyzed. The results show that among the five drought intensity indexes the process maximum intensity demonstrates the greatest correlation coefficient with the disaster rate of drought in North China. Therefore, the process maximum intensity of drought is selected as the annual drought intensity to analyze the drought characteristics in North China. According to the climate warming trends, the study period is divided into three stages, i.e., 1951–1984 (stage I), 1985–1997 (stage II) and 1998–2019(stage III). The comprehensive results show that the drought intensity in North China has significant stage characteristics. In stage I, the drought shows an increasing trend in most parts of North China, but its average intensity is relatively weaker, with a lower severe drought frequency. The drought also shows an increasing trend in most parts in stage II, with a more significant increase rate than that in stage I, and the average drought intensity is the strongest and the severe drought frequency is the highest. In stage III, the drought shows a decreasing trend in some areas, and the average intensity is the weakest, with a lower severe drought frequency.

Assessment of Soybean Resistance Level to Pod Sucking Bug Riptortus linearis F. (Hemiptera: Coreidae) based on No-choice and Free-choice Tests

Background: The infestation of the pod sucking bug Riptortus linearis is one of the limiting factors of soybean productivity in Indonesia. The research aims were to identify the level of resistance to the pod sucking bug R. linearis on several soybean genotypes based on the no-choice test (NCT) and free-choice tests (FCT). Methods: The genetic materials used were 49 soybean genotypes. The study was conducted in the Indonesian Legumes and Tuber Crops Research Institute (ILETRI) from August to December 2020, using the randomized block design in triplicates. The evaluation for pod sucking bug resistance was based on NCT and FCT. Result: The FCT resulted in two genotypes with a consistent moderately resistance level (20-40% of damage intensity) to pod sucking bug based on the pod and seed damage intensity. The NCT method resulted in five genotypes as moderately resistant (20-40% of damage intensity) to pod sucking bug based on the seed damage. The NCT resulted in higher average intensity of pod and seed damage (80.25% and 71.23%, respectively) than the FCT (69.91% and 69.09%, respectively). Two soybean genotypes (Degra/Anjasmoro-1-559 and Anjasmoro/IAC100-2-618) with a consistent moderately resistance level could be used for cultivar improvement in the breeding program. The pod trichome density was suggested to be one of the effective morphological defenses against the pod sucking bug attack.

Potential Usage of Solar Energy as a Renewable Energy Source in Petukangan Utara, South Jakarta

Indonesia is a tropical country located on the equator. The average intensity of solar radiation in Indonesia is 4.8 kWh/m2. This makes Indonesia a country with new and ren ewable energy potential, one of which is solar panel technology. The first step that must be done in the process of installing solar panels in a place is to analyze the potential of solar energy. In this study, an analysis of the potential of solar energy as a new renewable energy source has been carried out at Budi Luhur University, North Petukangan, South Jakarta. Based on the research results, the maximum photovoltaic efficiency that can be achieved is 21.45%. During the day, the efficiency of the solar panels increases along with the ncrease in the value of the voltage obtained. However, the higher the panel temperature, the lower the efficiency of the solar panel. Therefore, a cooling system is needed to anticipate this.

Optimization of coal tar gas chromatography conditions using probabilistic-deterministic design of experiment

The development of physicochemical methods for the analysis of objects of complex composition requires the application of methods of mathematical experiment design. This article investigates the possibility of using probabilistic-deterministic design of experiment (PDDoE) for obtaining a mathematical model of the chromatographic separation process of coal tar hydrogenation products on an Agilent 7890A device with an Rxi-5ms column. It is shown that the relationship between the column heating rate and the carrier gas pressure with the values averaged for the entire chromatogram can be established with a high accuracy. It is noted that the accuracy of modeling the individual characteristics of the mixture components’ peaks is less, but remains sufficient for many practical needs. Nonlinear multiple correlation coefficients (NMC) for the dependence of the average retention time and average intensity on the considered factors are more than 0.99; they are more than 0.98 for the average peak width. NMC for the dependence of the resolution with the relation to the peaks of naphthalene and 2-ethylphenol is more than 0.8 at a significant level that sufficient for practice. The quality of the mathematical model was checked by triple registration of the chromatogram at the values of the column heating rate and carrier gas pressure that were not used in the training experiment. The measurement results are excellent squared with those calculated using the obtained generalized equations. The PDDoE method can be recommended as a method for mathematical design of an optimization experiment in gas chromatography.

Identification of Regional Drought Processes in North China Using MCI Analysis

Comprehensive identification of drought events is of great significance for monitoring and evaluating drought processes. Based on the date of daily precipitation, temperature and drought-affected area of 403 meteorological stations in North China from 1960 to 2019, the Comprehensive Drought Process Intensity Index (CDPII) has been developed by using the Meteorological-drought Composite Index (MCI) and regional drought process identification method, as well as the EIDR theory method. The regional drought processes in the past 60 years in North China, including Beijing, Tianjin, Hebei, Shanxi and Middle Inner Mongolia, were analyzed and identified. The result shows that the distribution characteristic of droughts with different intensities is as follows: The number of days of all annual-average mild droughts, moderate droughts and severe droughts was highest in Tianjin and that of extreme droughts was highest in Shanxi. The number of days of mild droughts was highest in May and lowest in January. The number of days of moderate droughts was highest in June. The number of days with mild and moderate drought showed an overall increasing trend, while the number of days with severe drought and above showed an overall decreasing trend (through a 95% significance test). The number of drought days was the highest in the 1990s. The annual frequency of drought is between 66.7% and 86.7%; the drought frequency in Hebei is the highest at 86.7%, followed by Beijing at 80%. There were 75 regional drought processes in North China from 1960 to 2019, and the correlation coefficient between process intensity and the drought-affected area was 0.55, which passed the 99% significance test. The comprehensive intensity of drought process from 27 April to 1 September 1972 was the strongest. From 18 May to 31 October 1965, the drought lasted 167 days. The overall drought intensity had a slight weakening trend in the past 60 years. A total of 75 regional drought processes occurred in North China, and the process intensity showed a trend of wavy decline with a determination coefficient (R2) of 0.079 (95% significance test). Overall, the regional drought process identification method and strength assessment result tally with the drought disaster, which can better identify the regional drought process. Furthermore, including the last days, the average intensity, average scope comprehensive strength, there are many angles to monitor and evaluate the drought and drought process. These provide a reference for drought control and decision-making.

Average Intensity of Low-Frequency Sound and Its Fluctuations in a Shallow Sea with a Range-Dependent Random Impedance of the Liquid Bottom

In this study, the problem of the influence of a horizontally inhomogeneous liquid bottom impedance, given by random Gaussian function of the speed of sound and by density, on the propagation of low-frequency sound in a shallow-water waveguide is considered. The model parameters are referenced to the conditions of sound propagation in the regions of the seas of the Russian Arctic shelf. By the example of statistical modeling of the sound field intensity, we show that sound speed fluctuations in the bottom lead to similar effects that were previously established for volumetric fluctuations of the speed of sound in the water layer. With the distance from the source, the decrease in the average intensity slows down in comparison with a deterministic medium in which there are no fluctuations. This deceleration of the decay of the intensity in a random waveguide can be significant already at short distances. Changes in the law of decay of intensity at a fixed frequency are mainly determined by the correlation radius of inhomogeneities and the average penetrability of the bottom, which leads to attenuation of sound propagating in the waveguide.

MILKING EQUIPMENT OF " YALYNKA" (“HERRINGBONE”) "EUROCLASS 1200" TYPE TESTING RESULTS

The purpose of the research is – to evaluate the milking platform of "Yalynka" ("Herringbone") "EuroClass 1200" type manufactured by "GEA" (Germany) for milking cows based on the results of experimental testing. Research methods. During the testing of the milking parlor "Yalynka" "EuroClass 1200" type the quality of the technological process was determined using the methods described in ISO 5707:2007, ISO 6690:2007, DSTU 7435:2013 and DSTU 3662:2018, operational-technological and economic evaluation was carried out according to DSTU 8424:2015 and DSTU 4397:2005, safety and ergonomics of the equipment were determined according to DSTU EN ISO 12100:2014. Research results. According to the results of experimental testing, it was established that the milking parlor "Yalinka" "EuroClass 1200" type of German production at the appropriate level performs the technological process of machine milking of cows. The obtained research results showed that the average total milking time of one cow is 5,07 minutes, the average intensity of milk excretion as a whole during milking – 2,35 kg / min. Milk obtained during milking cows in terms of quality corresponds to the grade "Extra" in accordance with DSTU 3662: 2018. Devices for controlling the process of milking cows "DemaTron 70" and computer herd management system "Dairy Plan C21" perform the technological process of milking cows in automatic mode, control over the implementation of technical parameters of the milking process, milk accounting and shutdown of milking machines. Based on the results of conformity assessment of the construction of the milking parlor "Yalinka" "EuroClass 1200" type in terms of safety and ergonomics, it is established that it meets the requirements of DSTU EN 12100: 2014 and DSTU 60204-1: 2015 for items related to its design, which is the evidence base of its compliance with the Technical Regulations for the Safety of Machinery and the Technical Regulations for Low-Voltage Electrical Equipment. Productivity of the milking installation-platform makes 70 heads / hour. Serves the milking parlor 2 operators of machine milking. Electricity consumption per milking a cow is 0,13 kWh. Annual operating costs are 4247 UAH / head in the conditions of 3 times milking of cows. Conclusions. For the first time in Ukraine, experimental testing of the milking parlor "Yalinka" "EuroClass 1200" type showed that the equipment satisfactorily performs the technological process of machine milking of cows with their loose housing and provides milk of the "Extra" grade. The «Euroclass 1200» «Yalinka» milking parlor is characterized by a high technical level and can be widely used in Ukraine.

Estimation of Individual Tree Stem Biomass in an Uneven-Aged Structured Coniferous Forest Using Multispectral LiDAR Data

Stem biomass is a fundamental component of the global carbon cycle that is essential for forest productivity estimation. Over the last few decades, Light Detection and Ranging (LiDAR) has proven to be a useful tool for accurate carbon stock and biomass estimation in various biomes. The aim of this study was to investigate the potential of multispectral LiDAR data for the reliable estimation of single-tree total and barkless stem biomass (TSB and BSB) in an uneven-aged structured forest with complex topography. Destructive and non-destructive field measurements were collected for a total of 67 dominant and co-dominant Abies borisii-regis trees located in a mountainous area in Greece. Subsequently, two allometric equations were constructed to enrich the reference data with non-destructively sampled trees. Five different regression algorithms were tested for single-tree BSB and TSB estimation using height (height percentiles and bicentiles, max and average height) and intensity (skewness, standard deviation and average intensity) LiDAR-derived metrics: Generalized Linear Models (GLMs), Gaussian Process (GP), Random Forest (RF), Support Vector Regression (SVR) and Extreme Gradient Boosting (XGBoost). The results showcased that the RF algorithm provided the best overall predictive performance in both BSB (i.e., RMSE = 175.76 kg and R2 = 0.78) and TSB (i.e., RMSE = 211.16 kg and R2 = 0.65) cases. Our work demonstrates that BSB can be estimated with moderate to high accuracy using all the tested algorithms, contrary to the TSB, where only three algorithms (RF, SVR and GP) can adequately provide accurate TSB predictions due to bark irregularities along the stems. Overall, the multispectral LiDAR data provide accurate stem biomass estimates, the general applicability of which should be further tested in different biomes and ecosystems.