Regime of groundwater level is a comprehensive reflection of the hydrogeological environment from the perspective of groundwater. Based on the analysis of the water-level change of 65 groundwater monitoring points fro...Regime of groundwater level is a comprehensive reflection of the hydrogeological environment from the perspective of groundwater. Based on the analysis of the water-level change of 65 groundwater monitoring points from 1987 to 1990, it is found that intermittent cones of depression came into being due to groundwater exploitation in Guilin during the observation period. The buried depth of groundwater in the drawdown cones, the annual variation of water level and specific yield have higher values. Improvement has been made to the formula of infiltration coefficient of precipitation. By using the precipitation response data recorded at every 15 minutes for water level of No. 9 borehole which is near Zengpiyan Cave, the specific yield of phreatic variation zone is indirectly calculated by using the modified formula. The results are range from 0.012 to 0.462 and the spatial distribution of specific yield is ascertained. These make up the deficiency that empirical values cannot be categorized based on the actual conditions. What’s more, the widely used Aviriyanover’s empirical formula is poorly applicable to karst area. This is due to its strict requirement for outside conditions, such as shallow buried depth, homogeneous aquifer medium and small hydraulic gradient.展开更多
This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace applications.The composition of AlCrFeNiTi_(x) CCAs is strategi...This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace applications.The composition of AlCrFeNiTi_(x) CCAs is strategically guided by employing density functional theory and the theoretical design of thermodynamic calculations.Bulk CCAs,particularly AlCrFeNiTi_(0.25) alloy,demonstrate remarkable specific yield strength(1640.8 MPa) and 22.7% maximum strain.The incorporation of Ti facilitates the formation of lightweight and high-strength L2_(1)phase,contributing to the overall high specific strength.Synergistic effects of grain boundary strengthening,solid solution strengthening,Orowan strengthening and Peierls flow stress further enhance strength.Detailed exploration of micros tructural changes during fracture reveals the role of ordered phases in suppressing crack propagation and absorbing energy within disordered phases,thereby improving the toughness and fracture resistance of CCAs.These methods and discoveries establish a robust foundation for advancing the development of novel lightweight CCAs.展开更多
Quantifying the spatial and temporal distribution of natural groundwater recharge is essential for effective groundwater modeling and sustainable resource management.This paper presents M-RechargeCal,a user-friendly s...Quantifying the spatial and temporal distribution of natural groundwater recharge is essential for effective groundwater modeling and sustainable resource management.This paper presents M-RechargeCal,a user-friendly software tool developed to estimate natural groundwater recharge using two widely adopted approaches:the Water Balance(WB)method and Water Table Fluctuation(WTF)method.In the WB approach,the catchment area is divided into seven land-use categories,each representing distinct recharge characteristics.The tool includes eighteen different reference Evapotranspiration(ET0)estimation methods,accommodating varying levels of climatic input data availability.Additional required inputs include crop coefficients for major crops and Curve Numbers(CN)for specific land-use types.The WTF approach considers up to three aquifer layers with different specific yields(for unconfined aquifer)or storage coeffi-cient(for confined aquifer).It also takes into account groundwater withdrawal(draft)and lateral water movement within or outside the aquifer system.M-RechargeCal is process-based and does not require cali-bration.Its performance was evaluated using six datasets from humid-subtropical environments,demon-2 strating reliable results(R=0.867,r=0.93,RE=10.6%,PMARE=9.8,ENS=0.93).The model can be applied to defined hydrological or hydrogeological units such as watersheds,aquifers,or catchments,and can be used to assess the impacts of land-use/land-cover changes on hydrological components.However,it has not yet been tested in arid regions.M-RechargeCal provides modelers and planners with a practical,accessible tool for recharge estimation to support groundwater modeling and water resource planning.The software is available free of charge and can be downloaded from the author's institutional website or obtained by contacting the author via email.展开更多
Complex concentrated alloys(CCAs)containing the L2_(1)phase are recognized for their exceptional strength and thermal stability,positioning them as strong candidates for transformative applications in aerospace,energy...Complex concentrated alloys(CCAs)containing the L2_(1)phase are recognized for their exceptional strength and thermal stability,positioning them as strong candidates for transformative applications in aerospace,energy,and structural sectors.This investigation delves into the AlFexNiTiV_(40-x)(x=0,10,20,30,35,40;at%)CCAs,aiming to unlock the synergistic potential of BCC and L2_(1)phases.By conducting an in-depth analysis of microstructure,phase behavior,and mechanical properties,the intricate relationships between chemistry,structure,and properties are illuminated within this alloy system.The Al_(15)Fe_(35)Ni_(3)0Ti_(15)V_(5)alloy demonstrates remarkable mechanical properties,achieving a yield strength of 2140.9 MPa and ultimate compressive strength of 2699.7 MPa,primarily through solid solution strengthening and precipitation hardening.Notably,its low lattice mismatches and nanoprecipitate strengthening yield an impressive specific yield strength at 600℃(245.2 MPa(g·cm^(-3))^(-1)).Phase modulation achieves the synergistic optimization of specific strengths at both room and high temperatures in CCAs containing the L2_(1)phase,opening new avenues for designing advanced lightweight and high strength alloys for elevated-temperature applications.展开更多
Bamako’s geographic and demographic expansion is sure to increase the need for water, and the slow development of the water supply network seems unable to meet this need. The knowledge of the approximate quantity of ...Bamako’s geographic and demographic expansion is sure to increase the need for water, and the slow development of the water supply network seems unable to meet this need. The knowledge of the approximate quantity of water reaching the groundwater is crucial, given the high dependence of this city and its surrounding area on groundwater. The aim of this study is to estimate the average groundwater recharge on a monthly scale, based on measurements taken over a 24-month period by using Water Table Fluctuation (WTF). The monthly recharge values obtained from the 15 piezometers in the study area by using WTF method vary from 1.04 to 38.81 mm with an average value of 9.74 mm. As part of the precipitations, these values represent respectively 1.29%, 48.52% and 12.17% of monthly average precipitation. It appears in this study that despite the piezometers belonging to the same climatic zone, the recharge rate can be different because of many factors such as the thickness of the aquifers, the soil and geology type, the local land cover and land use activities.展开更多
Groundwater is a significant component of the hydrological cycle in arid and semi-arid areas. Its evapotranspiration is an important part of the water budget because many plants are groundwater-dependent. To restore t...Groundwater is a significant component of the hydrological cycle in arid and semi-arid areas. Its evapotranspiration is an important part of the water budget because many plants are groundwater-dependent. To restore the degraded ecosystems, the need is pressing to further our understanding of the groundwater evapotranspiration(ET_g) in arid and semi-arid areas. This study employed the White method to estimate ET_g at four sites in the Mu Us Sandy Land in northern China, and the four sites are covered by Salix psammophila(SP site), Artemisia ordosica(AO site), Poplar alba(PA site), and Carex enervis(CE site), respectively. The depth of groundwater table and the duration of drainage were taken into account in calculating the specific yield(S_y) to improve the accuracy of the ET_g estimats. Our results showed that from late May to early November 2013 the ET_g were 361.87(SP site), 372.53(AO site), 597.86(PA site) and 700.76 mm(CE site), respectively. The estimated ET_g rate was also species-dependent and the descending order of the ET_g rate for the four vegetation was: C. enervis, P. alba, A. ordosica, and S. psammophila. In addition, the depth of groundwater table has an obvious effect on the ET_g rate and the effect varied with the vegetation types. Furthermore, the evapotranspiration for the vegetation solely relying on the water supply from unsaturated layers above the groundwater table was much less than that for the vegetation heavily relying on the water supply from shallow aquifers.展开更多
The present study has been undertaken to depict spatial distribution of different aquifer parameters in the eastern part of Kushtia district through a detailed hydrogeological survey. For this investigation, 119 litho...The present study has been undertaken to depict spatial distribution of different aquifer parameters in the eastern part of Kushtia district through a detailed hydrogeological survey. For this investigation, 119 lithologs and 92 pumping test data have been used. These data have been processed, analyzed, interpreted and krigged for the spatial assessment of the aquifer properties viz. transmissivity, hydraulic conductivity, hydraulic diffusivity, specific yield, radius of influence, and specific drawdown. It is seen from the investigation that the transmissivity and hydraulic conductivity values obtained from the pumping tests of the wells are varying from 1811 m<sup>2</sup>/day to 2568 m<sup>2</sup>/day and 32.5 m/day and 61.5 m/day respectively, the hydraulic diffusivity being ranging from 181,143 m<sup>2</sup>/day to 256,788 m<sup>2</sup>/day. The estimated specific yield of 17.97% - 23.46% supports that the area is dominated with coarse grained sands. This study reveals that the distribution of deep tube wells in the area are not within the radius of influence (638 - 760 m) each other, but few shallow and hand tube wells existed within the radius of influence. The estimated specific draw down is varying from 57 m/cumec to 126.1 m/cumec. From the overall analysis, it is found that the area is favorable for groundwater exploration.展开更多
This study aims to characterize water table fluctuations and estimate groundwater recharge in the Tougou catchment located in the Sahel zone of Burkina Faso. Water table fluctuation and groundwater budget approaches a...This study aims to characterize water table fluctuations and estimate groundwater recharge in the Tougou catchment located in the Sahel zone of Burkina Faso. Water table fluctuation and groundwater budget approaches are developed on an experimental site equipped with observation wells. The trends of water fluctuations in the different layers of the weathering profile are similar. There is a time-lag response of groundwater recharge to the daily precipitation occurrences. The interaction between the upper (clayey alteration) and lower (transition zone-fractured schist complex) parts of the weathering profile shows that generally the hydraulic head in the upper part is higher than that of the lower part due to difference in drainage porosity. The latter varies at the catchment scale between 0.006 and 0.009 and is inversely proportional to the saturated thickness of the clayey alteration layer. The groundwater recharge is annually estimated between 36 and 49 mm, which correspond to 6% and 9% of mean annual rainfall in the catchment. Annual evapotranspiration was estimated to be about 223 to 443 mm.展开更多
Under the background of large-scale ecological restoration, China's southwestern karst region has become a hotspot of global vegetation cover “greening” in the past 20 years. However, because of geological const...Under the background of large-scale ecological restoration, China's southwestern karst region has become a hotspot of global vegetation cover “greening” in the past 20 years. However, because of geological constraints, it is difficult to restore the forest landscapes in some areas. It is urgent to understand the impacts of human disturbances during the historical period on the difficult-to-forestation rocky-desertification areas of the karst region in order to guide future afforestation. In this study, we quantified the changes of specific sediment yield in typical karst depressions over the past 500 years by using ^(137)Cs,^(210)Pb, and ^(14)C dating methods in karst depressions, and identified the main human disturbances related to historical erosion and sedimentation by combining with historical data. The results showed that the erosion and sedimentation of the three depressions in 1921–1963 were significantly higher than that in 1963–2021, and the sedimentation rate(0.64–1.33 cm a^(-1)) and the specific sediment yield(2.51–13.11 t ha^(-1)a^(-1)) during Ming and Qing dynasties(1504–1812) were higher than the sedimentation rate(0.26–0.95 cm a^(-1)) and specific sediment yield(0.95–6.99 t ha^(-1)a^(-1)) in the recent century(1921–2021). Reconstruction data and literature from the Ming and Qing dynasties show an empirical link between changes in population, arable land, food, forest area,and deforestation events during the same period. It was found that the population and arable land in Guangxi increased more than three-fold and the forest area decreased significantly in the 17th century after the migration of the Yao ethnic group and the introduction of maize to the region, which may be the main reason for intensifying the erosion of depressions. This study is of great significance to understanding the evolution history of rocky desertification in this region and to answer the potential of afforestation.展开更多
Analysis of photovoltaic power plant(PVPP)operations is important to both investors and users and to producers of equipment,researchers and designers as well.This paper presents the analysis of the year-long operation...Analysis of photovoltaic power plant(PVPP)operations is important to both investors and users and to producers of equipment,researchers and designers as well.This paper presents the analysis of the year-long operations of the group PVPPs in Serbia connected to the distribution network which was carried out through specific indicators such as electric power generation,power,capacity factors,specific yield,losses,period of cost effectiveness of the investment,etc.Special attention has been paid to the influence of the azimuth and tilt of the photovoltaic modules on the performances of PVPPs.Results obtained through the year-long extensive measurements were compared to expected yields of PVPPs on the basis of the Climate SAF PVGIS application.The results of the analysis indicate that available software applications cannot always provide a good enough forecast of expected electric power production since they cannot always assess well enough the effects of the surrounding facilities on operations of a PVPP.In addition,it has been found that the correlation between losses of annual achieved specific yield of a PVPP and the azimuth is represented by a polynomial of the second degree,whereas the correlation between losses of the annual achieved specific yield of a PVPP and the tilt is represented by an exponential function.展开更多
基金supported by National Natural Science Foundation of China(No.41172231)
文摘Regime of groundwater level is a comprehensive reflection of the hydrogeological environment from the perspective of groundwater. Based on the analysis of the water-level change of 65 groundwater monitoring points from 1987 to 1990, it is found that intermittent cones of depression came into being due to groundwater exploitation in Guilin during the observation period. The buried depth of groundwater in the drawdown cones, the annual variation of water level and specific yield have higher values. Improvement has been made to the formula of infiltration coefficient of precipitation. By using the precipitation response data recorded at every 15 minutes for water level of No. 9 borehole which is near Zengpiyan Cave, the specific yield of phreatic variation zone is indirectly calculated by using the modified formula. The results are range from 0.012 to 0.462 and the spatial distribution of specific yield is ascertained. These make up the deficiency that empirical values cannot be categorized based on the actual conditions. What’s more, the widely used Aviriyanover’s empirical formula is poorly applicable to karst area. This is due to its strict requirement for outside conditions, such as shallow buried depth, homogeneous aquifer medium and small hydraulic gradient.
基金financially supported by Guangdong Basic and Applied Basic Research Foundation (No. 2021A1515012626)Shenzhen Knowledge Innovation Plan-Fundamental Research (Discipline Distribution) (No. JCYJ20180507184623297)+1 种基金the National Natural Science Foundation of China (No.52301043)the Postdoctoral Research Startup Expenses of Shenzhen (No.NA25501001)。
文摘This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace applications.The composition of AlCrFeNiTi_(x) CCAs is strategically guided by employing density functional theory and the theoretical design of thermodynamic calculations.Bulk CCAs,particularly AlCrFeNiTi_(0.25) alloy,demonstrate remarkable specific yield strength(1640.8 MPa) and 22.7% maximum strain.The incorporation of Ti facilitates the formation of lightweight and high-strength L2_(1)phase,contributing to the overall high specific strength.Synergistic effects of grain boundary strengthening,solid solution strengthening,Orowan strengthening and Peierls flow stress further enhance strength.Detailed exploration of micros tructural changes during fracture reveals the role of ordered phases in suppressing crack propagation and absorbing energy within disordered phases,thereby improving the toughness and fracture resistance of CCAs.These methods and discoveries establish a robust foundation for advancing the development of novel lightweight CCAs.
文摘Quantifying the spatial and temporal distribution of natural groundwater recharge is essential for effective groundwater modeling and sustainable resource management.This paper presents M-RechargeCal,a user-friendly software tool developed to estimate natural groundwater recharge using two widely adopted approaches:the Water Balance(WB)method and Water Table Fluctuation(WTF)method.In the WB approach,the catchment area is divided into seven land-use categories,each representing distinct recharge characteristics.The tool includes eighteen different reference Evapotranspiration(ET0)estimation methods,accommodating varying levels of climatic input data availability.Additional required inputs include crop coefficients for major crops and Curve Numbers(CN)for specific land-use types.The WTF approach considers up to three aquifer layers with different specific yields(for unconfined aquifer)or storage coeffi-cient(for confined aquifer).It also takes into account groundwater withdrawal(draft)and lateral water movement within or outside the aquifer system.M-RechargeCal is process-based and does not require cali-bration.Its performance was evaluated using six datasets from humid-subtropical environments,demon-2 strating reliable results(R=0.867,r=0.93,RE=10.6%,PMARE=9.8,ENS=0.93).The model can be applied to defined hydrological or hydrogeological units such as watersheds,aquifers,or catchments,and can be used to assess the impacts of land-use/land-cover changes on hydrological components.However,it has not yet been tested in arid regions.M-RechargeCal provides modelers and planners with a practical,accessible tool for recharge estimation to support groundwater modeling and water resource planning.The software is available free of charge and can be downloaded from the author's institutional website or obtained by contacting the author via email.
基金supported by the National Natural Science Foundation of China(Nos.52301043 and 51871077)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515012626),Shenzhen Knowledge Innovation Plan-Fundamental Research(Discipline Distribution)(No.JCYJ20180507184623297)+1 种基金Shenzhen Science and Technology Plan-Technology Innovation(No.KQJSCX20180328165656256)the Startup Foundation from Shenzhen(Nos.NA25501001,and NA11409005).
文摘Complex concentrated alloys(CCAs)containing the L2_(1)phase are recognized for their exceptional strength and thermal stability,positioning them as strong candidates for transformative applications in aerospace,energy,and structural sectors.This investigation delves into the AlFexNiTiV_(40-x)(x=0,10,20,30,35,40;at%)CCAs,aiming to unlock the synergistic potential of BCC and L2_(1)phases.By conducting an in-depth analysis of microstructure,phase behavior,and mechanical properties,the intricate relationships between chemistry,structure,and properties are illuminated within this alloy system.The Al_(15)Fe_(35)Ni_(3)0Ti_(15)V_(5)alloy demonstrates remarkable mechanical properties,achieving a yield strength of 2140.9 MPa and ultimate compressive strength of 2699.7 MPa,primarily through solid solution strengthening and precipitation hardening.Notably,its low lattice mismatches and nanoprecipitate strengthening yield an impressive specific yield strength at 600℃(245.2 MPa(g·cm^(-3))^(-1)).Phase modulation achieves the synergistic optimization of specific strengths at both room and high temperatures in CCAs containing the L2_(1)phase,opening new avenues for designing advanced lightweight and high strength alloys for elevated-temperature applications.
文摘Bamako’s geographic and demographic expansion is sure to increase the need for water, and the slow development of the water supply network seems unable to meet this need. The knowledge of the approximate quantity of water reaching the groundwater is crucial, given the high dependence of this city and its surrounding area on groundwater. The aim of this study is to estimate the average groundwater recharge on a monthly scale, based on measurements taken over a 24-month period by using Water Table Fluctuation (WTF). The monthly recharge values obtained from the 15 piezometers in the study area by using WTF method vary from 1.04 to 38.81 mm with an average value of 9.74 mm. As part of the precipitations, these values represent respectively 1.29%, 48.52% and 12.17% of monthly average precipitation. It appears in this study that despite the piezometers belonging to the same climatic zone, the recharge rate can be different because of many factors such as the thickness of the aquifers, the soil and geology type, the local land cover and land use activities.
基金funded by the National Natural Science Foundation of China (41072184, 41472220)the Special Fund for Basic Scientific Research of Central Colleges, Chang’an University (310829162015)
文摘Groundwater is a significant component of the hydrological cycle in arid and semi-arid areas. Its evapotranspiration is an important part of the water budget because many plants are groundwater-dependent. To restore the degraded ecosystems, the need is pressing to further our understanding of the groundwater evapotranspiration(ET_g) in arid and semi-arid areas. This study employed the White method to estimate ET_g at four sites in the Mu Us Sandy Land in northern China, and the four sites are covered by Salix psammophila(SP site), Artemisia ordosica(AO site), Poplar alba(PA site), and Carex enervis(CE site), respectively. The depth of groundwater table and the duration of drainage were taken into account in calculating the specific yield(S_y) to improve the accuracy of the ET_g estimats. Our results showed that from late May to early November 2013 the ET_g were 361.87(SP site), 372.53(AO site), 597.86(PA site) and 700.76 mm(CE site), respectively. The estimated ET_g rate was also species-dependent and the descending order of the ET_g rate for the four vegetation was: C. enervis, P. alba, A. ordosica, and S. psammophila. In addition, the depth of groundwater table has an obvious effect on the ET_g rate and the effect varied with the vegetation types. Furthermore, the evapotranspiration for the vegetation solely relying on the water supply from unsaturated layers above the groundwater table was much less than that for the vegetation heavily relying on the water supply from shallow aquifers.
文摘The present study has been undertaken to depict spatial distribution of different aquifer parameters in the eastern part of Kushtia district through a detailed hydrogeological survey. For this investigation, 119 lithologs and 92 pumping test data have been used. These data have been processed, analyzed, interpreted and krigged for the spatial assessment of the aquifer properties viz. transmissivity, hydraulic conductivity, hydraulic diffusivity, specific yield, radius of influence, and specific drawdown. It is seen from the investigation that the transmissivity and hydraulic conductivity values obtained from the pumping tests of the wells are varying from 1811 m<sup>2</sup>/day to 2568 m<sup>2</sup>/day and 32.5 m/day and 61.5 m/day respectively, the hydraulic diffusivity being ranging from 181,143 m<sup>2</sup>/day to 256,788 m<sup>2</sup>/day. The estimated specific yield of 17.97% - 23.46% supports that the area is dominated with coarse grained sands. This study reveals that the distribution of deep tube wells in the area are not within the radius of influence (638 - 760 m) each other, but few shallow and hand tube wells existed within the radius of influence. The estimated specific draw down is varying from 57 m/cumec to 126.1 m/cumec. From the overall analysis, it is found that the area is favorable for groundwater exploration.
文摘This study aims to characterize water table fluctuations and estimate groundwater recharge in the Tougou catchment located in the Sahel zone of Burkina Faso. Water table fluctuation and groundwater budget approaches are developed on an experimental site equipped with observation wells. The trends of water fluctuations in the different layers of the weathering profile are similar. There is a time-lag response of groundwater recharge to the daily precipitation occurrences. The interaction between the upper (clayey alteration) and lower (transition zone-fractured schist complex) parts of the weathering profile shows that generally the hydraulic head in the upper part is higher than that of the lower part due to difference in drainage porosity. The latter varies at the catchment scale between 0.006 and 0.009 and is inversely proportional to the saturated thickness of the clayey alteration layer. The groundwater recharge is annually estimated between 36 and 49 mm, which correspond to 6% and 9% of mean annual rainfall in the catchment. Annual evapotranspiration was estimated to be about 223 to 443 mm.
基金supported by the National Natural Science Foundation of China (Grant Nos. U20A2048 & 41930652)the National Key Research and Development Program of China (Grant No. 2022YFF1300700)。
文摘Under the background of large-scale ecological restoration, China's southwestern karst region has become a hotspot of global vegetation cover “greening” in the past 20 years. However, because of geological constraints, it is difficult to restore the forest landscapes in some areas. It is urgent to understand the impacts of human disturbances during the historical period on the difficult-to-forestation rocky-desertification areas of the karst region in order to guide future afforestation. In this study, we quantified the changes of specific sediment yield in typical karst depressions over the past 500 years by using ^(137)Cs,^(210)Pb, and ^(14)C dating methods in karst depressions, and identified the main human disturbances related to historical erosion and sedimentation by combining with historical data. The results showed that the erosion and sedimentation of the three depressions in 1921–1963 were significantly higher than that in 1963–2021, and the sedimentation rate(0.64–1.33 cm a^(-1)) and the specific sediment yield(2.51–13.11 t ha^(-1)a^(-1)) during Ming and Qing dynasties(1504–1812) were higher than the sedimentation rate(0.26–0.95 cm a^(-1)) and specific sediment yield(0.95–6.99 t ha^(-1)a^(-1)) in the recent century(1921–2021). Reconstruction data and literature from the Ming and Qing dynasties show an empirical link between changes in population, arable land, food, forest area,and deforestation events during the same period. It was found that the population and arable land in Guangxi increased more than three-fold and the forest area decreased significantly in the 17th century after the migration of the Yao ethnic group and the introduction of maize to the region, which may be the main reason for intensifying the erosion of depressions. This study is of great significance to understanding the evolution history of rocky desertification in this region and to answer the potential of afforestation.
文摘Analysis of photovoltaic power plant(PVPP)operations is important to both investors and users and to producers of equipment,researchers and designers as well.This paper presents the analysis of the year-long operations of the group PVPPs in Serbia connected to the distribution network which was carried out through specific indicators such as electric power generation,power,capacity factors,specific yield,losses,period of cost effectiveness of the investment,etc.Special attention has been paid to the influence of the azimuth and tilt of the photovoltaic modules on the performances of PVPPs.Results obtained through the year-long extensive measurements were compared to expected yields of PVPPs on the basis of the Climate SAF PVGIS application.The results of the analysis indicate that available software applications cannot always provide a good enough forecast of expected electric power production since they cannot always assess well enough the effects of the surrounding facilities on operations of a PVPP.In addition,it has been found that the correlation between losses of annual achieved specific yield of a PVPP and the azimuth is represented by a polynomial of the second degree,whereas the correlation between losses of the annual achieved specific yield of a PVPP and the tilt is represented by an exponential function.