Analysis of high resolution of aeromagnetic data was carried out over Lamurde, Adamawa state north-eastern Nigeria to determine the Curie point depth (CPD), heat flow and geothermal gradient. The aeromagnetic data use...Analysis of high resolution of aeromagnetic data was carried out over Lamurde, Adamawa state north-eastern Nigeria to determine the Curie point depth (CPD), heat flow and geothermal gradient. The aeromagnetic data used for this work was obtained at Nigerian geological survey agency, the total magnetic intensity was processed to produce the residual magnetic map which was divided into 4 overlapping blocks, each block was subjected to spectral analyses to obtain depths to the top boundary and centroid, while depth to bottom of the magnetic sources was calculated using empirical formula. The depths values obtained were then used to assess the CPD, heat flow and geothermal gradient in the area. The result shows that the CPD varies between 9.62 and 10.92 km with an average of 10.45 k, the heat flow varies between 150.73 and 132.78 mWm−20⋅°C−1 with an average of 139.12 mWm−20⋅°C−1 and the geothermal gradient in the study area varies between 12.16 and 15.67 °C/km with an average of 13.39 °C/km. In view of the above results, the high heat flow may be responsible for maturation of hydrocarbon in Benue Trough as well as responsible for the lead Zinc Mineralization. Again by implication, Lamurde area can be a good area for geothermal reservoir exploration for an alternative source for power generation.展开更多
In some cases, if the insertion depth is shallower than expected, intramuscular (IM) injection of risperidone long-acting injectable (RLAI) may not penetrate the muscle fascia. However, if needle insertion depth is de...In some cases, if the insertion depth is shallower than expected, intramuscular (IM) injection of risperidone long-acting injectable (RLAI) may not penetrate the muscle fascia. However, if needle insertion depth is deeper than anticipated, needle penetration may cause damage to nerves, arteries and veins. Few clinical studies were done to evaluate the depth of needle length insertion reaching the intended gluteal muscle. The aim of this study was to evaluate the suitable depth of injecting RLAI. Twenty-six patients with schizophrenia were treated with RLAI, and randomly divided into two groups: 50 mm needle inserted group (Group-D, deep insertion, n = 13) and 20 mm needle insertion group (Group-S, shallow insertion, n = 13). For Group-S, the needle length was marked with a spacer at exactly 20 mm. Injections were performed by the psychiatrist or nurse, alternating between the two gluteal sites by double-cross method every two weeks. Clinical psychotic symptoms and injection site reactions were recorded throughout the study period. Experienced psychologists who were blinded from the needle-length experimental variable evaluated patients’ psychotic symptoms using the Positive and Negative Syndrome Scale (PANSS) every two weeks. The plasma 9-hydroxyrisperidone (9-OH-RIS) concentrations were measured every two weeks;comparison data were determined on the 8th week and the 14th week. No significant difference was observed in 9-OH-RIS concentrations, psychotic symptoms, injection site skin reactions of subjects in both groups. However, in Group-D, injection site adverse reactions were confirmed in two subjects (15%). In Group-S, injection site reactions were confirmed in six subjects (46%). Although effective 9-OH-RIS concentrations were obtained with the insertion using both depth, it was concluded that the 50 mm insertion length was more suitable for dorsogluteal IM injections in adult patients with schizophrenia as demonstrated by the incidence of local adverse skin reactions.展开更多
The problem of water wave scattering by a thin vertical elastic plate submerged in uniform finite depth water is investigated here.The boundary condition on the elastic plate is derived from the Bernoulli-Euler equati...The problem of water wave scattering by a thin vertical elastic plate submerged in uniform finite depth water is investigated here.The boundary condition on the elastic plate is derived from the Bernoulli-Euler equation of motion satisfied by the plate.Using the Green’s function technique,from this boundary condition,the normal velocity of the plate is expressed in terms of the difference between the velocity potentials(unknown)across the plate.The two ends of the plate are either clamped or free.The reflection and transmission coefficients are obtained in terms of the integrals’involving combinations of the unknown velocity potential on the two sides of the plate,which satisfy three simultaneous integral equations and are solved numerically.These coefficients are computed numerically for various values of different parameters and depicted graphically against the wave number in a number of figures.展开更多
We selected the 103 M_L≥2. 5 earthquake waveform data from the Inner Mongolia-Ningxia border during 2009-2015,which was recorded by the Inner Mongolia Digital Seismic Networks and used the simplex method, Hyposat met...We selected the 103 M_L≥2. 5 earthquake waveform data from the Inner Mongolia-Ningxia border during 2009-2015,which was recorded by the Inner Mongolia Digital Seismic Networks and used the simplex method, Hyposat method, double difference location method,and deterministic method (PTD) for the determination of focal depth,and compared the results. The CAP moment tensor inversion method is used to determine the focal depths of the Alxa Left Banner M5. 8 and M4. 2 earthquakes. The final results of the focal depth by the deterministic method (PTD) and the double difference location method fit well with the tectonic characteristics of the Inner Mongolia-Ningxia border area,but those of the simplex method and the Hyposat method do not. The average depth of the Inner Mongolia-Ningxia border seismic tectonic zone is 13. 32 ± 8 km.展开更多
AA5454-O aluminum alloy plates with thicknesses of 1.4 and 1.0 mm were friction-stir-lap-welded (FSLWed).The influences of the tool plunge depth and welding distance on surface appearance,macrostructure and mechanical...AA5454-O aluminum alloy plates with thicknesses of 1.4 and 1.0 mm were friction-stir-lap-welded (FSLWed).The influences of the tool plunge depth and welding distance on surface appearance,macrostructure and mechanical properties of the FSLWed plates were experimentally investigated.The tensile shear load of the FSLWed plates was compared with that of the adhesive-bonded plates.Defect-free FSLWed zones were successfully obtained in all the tool plunge depths and the welding distances.The FSLWed zones exhibited the relatively smooth surface morphologies.Under all the FSLWed conditions,the FSLWed zone exhibited higher average hardness than the base metal.In addition,the upper plate exhibited a higher average hardness than the lower plate,although there was no special tendency in spite of the change in the tool plunge depth and the welding distance.The maximum tensile shear load of the FSLWed plates was much higher than that of the adhesive-bonded aluminum alloy plate.Especially,under the FSLW condition of the plunge depth of 1.8 mm and the welding distance of 40 mm,the tensile shear load of the FSLWed plate reached a level about 41% greater than that of the adhesive-bonded aluminum alloy plate.In addition,the maximum tensile shear load of the FSLWed plate was increased with the increase of the welding distance.展开更多
Recent studies have explored the relationship between aerosol optical depth (AOD) measurements by satellite sensors and concentrations of particulate matter with aerodynamic diameters less than 2.5 μm (PM2.5). Howeve...Recent studies have explored the relationship between aerosol optical depth (AOD) measurements by satellite sensors and concentrations of particulate matter with aerodynamic diameters less than 2.5 μm (PM2.5). However, relatively little is known about spatial and temporal patterns in this relationship across the contiguous United States. In this study, we investigated the relationship between US Environmental Protection Agency estimates of PM2.5 concentrations and Moderate Resolution Imaging Spectroradiometer (MODIS) AOD measurements provided by two NASA satellites (Terra and Aqua) across the contiguous United States during 2005. We found that the combined use of both satellite sensors provided more AOD coverage than the use of either satellite sensor alone, that the correlation between AOD measurements and PM2.5 concentrations varied substantially by geographic location, and that this correlation was stronger in the summer and fall than that in the winter and spring.展开更多
Bathymetric measurement of shallow water is of fundamental importance to coastal environment research and resource management.However,there are still great challenges in estimating water depth using satellite observat...Bathymetric measurement of shallow water is of fundamental importance to coastal environment research and resource management.However,there are still great challenges in estimating water depth using satellite observations in turbid coastal waters.In this paper,we developed a physicsenhanced deep neural network to estimate bathymetry of highly turbid waters of the Changjiang(Yangtze)River estuary from dual-polarized synthetic aperture radar(SAR)images.Sentinel-1A/B SAR images with a spatial resolution of 20 m×22 m were collected and matched with water depth data from nautical charts during 2017-2023.For the input parameters of the model,in addition to the normalized radar backscatter cross section(NRCS)at single polarization and incidence angle,the impacts of both polarimetric characteristics and physical environmental factors on model performance were discussed in detail.Results of feature importance analysis and sensitivity experiments indicate that the polarization ratio and NRCS after removing the influence of background sea surface wind field make significant contributions to the bathymetry retrieval model.The root mean square error(RMSE)of SAR derived water depth decreases from 1.44 to 0.78 m within 0-30-m depth,and the mean relative error(MRE)is reduced from 15.6%to 8.6%.Compared with other machine learning models such as ResNet,XGBoost,and Random Forest,the MRE is reduced by 3.9%,5.7%,and 7.4%,respectively.The spatial distribution of SAR derived water depth also exhibits a high degree of consistency with observations,demonstrating the great potential of the model in estimating the depth of turbid shallow waters.展开更多
In this study,FLUENT software was employed to simulate the flow pattern and water depth changes in a 120° sharp bend at four discharge rates.To verify the numerical model,a 90° sharp bend was first modeled w...In this study,FLUENT software was employed to simulate the flow pattern and water depth changes in a 120° sharp bend at four discharge rates.To verify the numerical model,a 90° sharp bend was first modeled with a three-dimensional numerical model,and the results were compared with available experimental results.Based on the numerical model validation,a 120° bend was simulated.The results show that the rate of increase of the water depth at the cross-section located 40 cm before the bend,compared with the cross-sections located 40 cm and 80 cm after the bend,decreases with the increase of the normal water depth in the 120° curved channel.Moreover,with increasing normal water depth,the dimensionless water depth change decreases at all cross-sections.At the interior cross-sections of the bend,the transverse water depth slope of the inner half-width is always greater than that of the outer half-width of the channel.Hence,the water depth slope is nonlinear at each crosssection in sharp bends.Two equations reflecting the relationships between the maximum and minimum dimensionless water depths and the normal water depth throughout the channel were obtained.展开更多
The presence of grassland biomes and species cannot be predicted by examining bottom up causes such as precipitation and temperature. Top down causes including herbivory and fire seem to be major controlling aspects w...The presence of grassland biomes and species cannot be predicted by examining bottom up causes such as precipitation and temperature. Top down causes including herbivory and fire seem to be major controlling aspects with other factors secondary. We examined soil depth and competitive ability of two North American C4 grasses in a greenhouse experiment. Changes in dry mass were determined and competitive intensity was calculated for both species. Species were grown separately or together in pots 30, 90, or 180 cm deep. When grown in monoculture, Schizachyrium scoparium total and belowground dry mass increased from the 30 to 90 cm depth, with no further significant increase from 90 to 180 cm. Aboveground dry mass did not increase significantly with depth. Total dry mass of Buchloe dactyloides increased significantly with depth when grown in monoculture. Aboveground dry mass increased from 30 to 90 cm depth but not from 90 to 180 cm. Belowground dry mass of B. dactyloides did not increase significantly with depth. In 180 cm pots, 53% of S. scoparium root dry mass was in the top 30 cm;74% of B. dactyloides root dry mass was in the top 30 cm. Roots of B. dactyloides were not found deeper than 90 cm. Aboveground dry mass of S. scoparium was not different in mixture or monoculture at any depth. Buchloe dactyloides aboveground dry mass in mixture was significantly lower than monoculture at the 30 cm depth, but not at 90 or 180 cm. The greatest competitive intensity was in the shallow soil pots. Soil depth could partially explain mosaics found in C4 grasslands where both species were found together with S. scoparium on deeper soils and B. dactyloides on shallower soils.展开更多
The prediction of indentation depth of abrasive grain in hydrophilic fixed-abrasive(FA)lapping is crucial for controlling material removal rate and surface quality of the work-piece being machined.By applying the theo...The prediction of indentation depth of abrasive grain in hydrophilic fixed-abrasive(FA)lapping is crucial for controlling material removal rate and surface quality of the work-piece being machined.By applying the theory of contact mechanics,a theoretical model of the indentation depth of abrasive grain was developed and the relationships between indentation depth and properties of contact pairs and abrasive back-off were studied.Also,the average surface roughness(Ra)of lapped wafer was approximately calculated according to the obtained indentation depth.To verify the rationality of the proposed model,a series of lapping experiments on lithium niobate(LN)wafers were carried out,whose average surface roughness Ra was measured by atomic force microscope(AFM).The experimental results were coincided with the theoretical predictions,verifying the rationality of the proposed model.It is concluded that the indentation depth of the fixed abrasive was primarily affected by the applied load,wafer micro hardness and pad Young′s modulus and so on.Moreover,the larger the applied load,the more significant the back-off of the abrasive grain.The model established in this paper is helpful to the design of FA pad and its machining parameters,and the prediction of Ra as well.展开更多
Aiming at the problems of low detection accuracy and large model size of existing object detection algorithms applied to complex road scenes,an improved you only look once version 8(YOLOv8)object detection algorithm f...Aiming at the problems of low detection accuracy and large model size of existing object detection algorithms applied to complex road scenes,an improved you only look once version 8(YOLOv8)object detection algorithm for infrared images,F-YOLOv8,is proposed.First,a spatial-to-depth network replaces the traditional backbone network's strided convolution or pooling layer.At the same time,it combines with the channel attention mechanism so that the neural network focuses on the channels with large weight values to better extract low-resolution image feature information;then an improved feature pyramid network of lightweight bidirectional feature pyramid network(L-BiFPN)is proposed,which can efficiently fuse features of different scales.In addition,a loss function of insertion of union based on the minimum point distance(MPDIoU)is introduced for bounding box regression,which obtains faster convergence speed and more accurate regression results.Experimental results on the FLIR dataset show that the improved algorithm can accurately detect infrared road targets in real time with 3%and 2.2%enhancement in mean average precision at 50%IoU(mAP50)and mean average precision at 50%—95%IoU(mAP50-95),respectively,and 38.1%,37.3%and 16.9%reduction in the number of model parameters,the model weight,and floating-point operations per second(FLOPs),respectively.To further demonstrate the detection capability of the improved algorithm,it is tested on the public dataset PASCAL VOC,and the results show that F-YOLO has excellent generalized detection performance.展开更多
Perfect anomalous reflections have been demonstrated in optical phase gradient metasurfaces(PGMs),but they suffer from single-frequency(narrow-band)response due to the intrinsic limitation of natural geometric periodi...Perfect anomalous reflections have been demonstrated in optical phase gradient metasurfaces(PGMs),but they suffer from single-frequency(narrow-band)response due to the intrinsic limitation of natural geometric periodicity.Here,we provide both numerical and analytical evidence that a depth gradient metasurface can achieve discrete ultra-broadband perfect anomalous reflection in the microwave range in the absence of geometric periodicity.Remarkably,by adjusting the operating frequency of the incident wave,the same effect can be steadily obtained via a physically equivalent phase periodicity in the PGM.Based on this mechanism,a perfect retroreflector with a broadband response ranging from 1 GHz to 40 GHz is realized.Our work has promising applications in communication,source tracking,and military satellites.展开更多
Background: Foraging theory predicts that animals select patches that offer the highest net rate of energy gain. Hence, prey distribution patterns and spatiotemporal heterogeneity play important roles in determining a...Background: Foraging theory predicts that animals select patches that offer the highest net rate of energy gain. Hence, prey distribution patterns and spatiotemporal heterogeneity play important roles in determining animal feeding patch selection. For waterfowl foraging on buried aquatic plant tubers, the distribution and biomass of these plant organs vary with depth in the substrate. Since excavation costs also increase with depth, the energy intake of the animals foraging on these plants is highly sediment depth dependent. Methods: Here, using observations of Swan Geese (Anser cygnoides) foraging on Vallisneria natans tubers, we test our hypothesis that geese feeding on tubers buried at intermediate sediment depth maximize their daily energy intake because of the interaction between tuber size and abundance with depth. To do this, we measured the distribution patterns of buried Vallisneria tubers under both undisturbed conditions and post-exploitation by geese (i.e. giving-up conditions). We investigated the relationship between tuber size and burial depth, and total tuber biomass within each sediment layer in undisturbed and exploited plots. Finally, we compared modelled Swan Goose daily energy intake feeding on Vallisneria tubers buried at different sediment layers (1–10, 11–20 and 21–30 cm below the surface). Results: Dry weight of Vallisneria tubers linearly increased with burial depth, while average total dry weight density of tubers showed a unimodal relationship, peaking at intermediate levels. Not surprisingly, Swan Geese foraged most intensively on tubers buried at intermediate sediment depths, where they maximize their daily energy intake. Our results support our hypothesis that Swan Geese feeding on tubers at intermediate depths maximize their daily energy intake. Conclusions: Our study is the first to quantify foraging strategies of Swan Geese during the wintering period, emphasizing the importance of plant traits on foraging selection of belowground foragers.展开更多
This paper outlines the application of the multi-layer perceptron artificial neural network (ANN), ordinary kriging (OK), and inverse distance weighting (IDW) models in the estimation of local scour depth around bridg...This paper outlines the application of the multi-layer perceptron artificial neural network (ANN), ordinary kriging (OK), and inverse distance weighting (IDW) models in the estimation of local scour depth around bridge piers. As part of this study, bridge piers were installed with bed sills at the bed of an experimental flume. Experimental tests were conducted under different flow conditions and varying distances between bridge pier and bed sill. The ANN, OK and IDW models were applied to the experimental data and it was shown that the artificial neural network model predicts local scour depth more accurately than the kriging and inverse distance weighting models. It was found that the ANN with two hidden layers was the optimum model to predict local scour depth. The results from the sixth test case showed that the ANN with one hidden layer and 17 hidden nodes was the best model to predict local scour depth. Whereas the results from the fifth test case found that the ANN with three hidden layers was the best model to predict local scour depth.展开更多
For the issue of proppant embedment in hydraulic fracturing,a new calculation method of embedment depth considering elastic-plastic deformation was proposed based on the mechanism of proppant embedment into rocks by c...For the issue of proppant embedment in hydraulic fracturing,a new calculation method of embedment depth considering elastic-plastic deformation was proposed based on the mechanism of proppant embedment into rocks by combining proppant embedment constitutive equations and contact stresses on the rock-proppant system.And factors affecting embedment depth of proppant were analyzed using the new method.Compared with the elastic embedment model,the results calculated by the new method match well with the experimental data,proving the new method is more reliable and more convenient to make theoretical calculation and analysis.The simulation results show the process of proppant embedment into rocks is mainly elastic-plastic.The embedment depth of monolayer proppants decreases with higher proppant concentration.Under multi-layer distribution conditions,increasing the proppant concentration will not change its embedment depth.The larger the proppant embedment ratio,the more the stress-bearing proppants,and the smaller the embedment depth will be.The embedment depth under higher closure stress is more remarkable.The embedment depth increased with the drawdown of fluid pressure in the fracture.Increasing proppant radius or the ratio of proppant Young’s modulus to rock Young’s modulus can reduce the proppant embedment depth.展开更多
Concrete carbonation relates to the diffusion of CO2 inthe atmosphere through the concrete pores and to the dissolution of the hydrates. A great deal of uncertainty still remains in this subject as a result of the ran...Concrete carbonation relates to the diffusion of CO2 inthe atmosphere through the concrete pores and to the dissolution of the hydrates. A great deal of uncertainty still remains in this subject as a result of the random nature of the infiltration of these aggressive agents as well as the material and structural properties of reinforced concrete. Consequently, in order to determine the degradation of these structures with time, it is necessary to approach the subject from a probabilistic point of view that it considers the uncertainties involved with the geometrical dimensions of these structures, with the material characteristics and with the environment and the subsequent deterioration that it provokes. The aim of this paper is the evaluation of carbonation depth (Xc) from a probabilistic analysis, focusing specifically on the study of the randomness of the most influential parameters on the reinforced concrete carbonation.展开更多
AIM To clarify the diagnostic efficacy and limitations of endoscopic ultrasonography(EUS) and the characteristics of early gastric cancers(EGCs) that are indications for EUS-based assessment of cancer invasion depth.M...AIM To clarify the diagnostic efficacy and limitations of endoscopic ultrasonography(EUS) and the characteristics of early gastric cancers(EGCs) that are indications for EUS-based assessment of cancer invasion depth.METHODS We retrospectively investigated the cases of 153 EGC patients who underwent conventional endoscopy(CE) and EUS(20 MHz) before treatment.RESULTS We found that 13.7% were "inconclusive" cases with low-quality EUS images, including all nine of the cases with protruded(0-I)-type EGCs. There was no significant difference in the diagnostic accuracybetween CE and EUS. Two significant independent risk factors for misdiagnosis by EUS were identified-ulcer scarring [UL(+); odds ratio(OR) = 4.49, P = 0.003] and non-indication criteria for endoscopic resection(ER)(OR = 3.02, P = 0.03). In the subgroup analysis, 23.1% of the differentiated-type cancers exhibiting SM massive invasion(SM2) invasion(submucosal invasion ≥ 500 μm) by CE were correctly diagnosed by EUS, and 23.1% of the undifferentiated-type EGCs meeting the expanded-indication criteria for ER were correctly diagnosed by EUS.CONCLUSION There is no need to perform EUS for UL(+) EGCs or 0-I-type EGCs, but EUS may enhance the pretreatment staging of differentiated-type EGCs with SM2 invasion without UL or undifferentiated-type EGCs revealed by CE as meeting the expanded-indication criteria for ER.展开更多
Ejina rangeland is located in Alashan Laegue, west part of Innermongolian Autono-mous Region with a area of 1.22×10~4 square Km of which the available area is 6940 squareKm, Because the varieties of reasons, such...Ejina rangeland is located in Alashan Laegue, west part of Innermongolian Autono-mous Region with a area of 1.22×10~4 square Km of which the available area is 6940 squareKm, Because the varieties of reasons, such as natural, human, historic and present, therunoff of Ejina River is decreased year by year, the irrigated area of the rangeland is de-creased. The deterioration of the ecologic environment is caused by the degeneration of展开更多
Recognition of the human actions by computer vision has become an active research area in recent years. Due to the speed and the high similarity of the actions, the current algorithms cannot get high recognition rate....Recognition of the human actions by computer vision has become an active research area in recent years. Due to the speed and the high similarity of the actions, the current algorithms cannot get high recognition rate. A new recognition method of the human action is proposed with the multi-scale directed depth motion maps(MsdDMMs) and Log-Gabor filters. According to the difference between the speed and time order of an action, MsdDMMs is proposed under the energy framework. Meanwhile, Log-Gabor is utilized to describe the texture details of MsdDMMs for the motion characteristics. It can easily satisfy both the texture characterization and the visual features of human eye. Furthermore, the collaborative representation is employed as action recognition by the classification. Experimental results show that the proposed algorithm, which is applied in the MSRAction3 D dataset and MSRGesture3 D dataset, can achieve the accuracy of 95.79% and 96.43% respectively. It also has higher accuracy than the existing algorithms, such as super normal vector(SNV), hierarchical recurrent neural network(Hierarchical RNN).展开更多
Objective:To observe the effects of different anesthesia depths on the level of plasma cortisol during operation and the score of postoperative MMSE in elderly patients underwent radical gastrectomy.Methods: A total o...Objective:To observe the effects of different anesthesia depths on the level of plasma cortisol during operation and the score of postoperative MMSE in elderly patients underwent radical gastrectomy.Methods: A total of eighty seven elderly patients undergoing radical gastrectomy were enrolled in this study. Continuous infusion of propofol and remifentanil for anesthesia and maintenance of propofol were divided into two groups: BIS-I (BIS: 45-55) and BIS-II (BIS: 55-65) by adusting the doses of propofol. The data were recorded as following, thewhole dosage of propofol, the time of extubation and the score of VAS. The level of plasma cortisol was finished at the time of incision and tracheal intubation. MMSE scores were recorded on the day before operation and follow-up at 3 and 7 d postoperatively. Record the patient's operation to discharge time, postoperative complications.Results: The concentration of cortisol in BIS-I group was higher than that in BIS-II group. There was no significant difference in extubation time, extubation VAS score and MMSE score after operation.Conclusion:There were no significant differences in the BIS values between 45 and 65 for the elderly patients undergoing upper abdominal surgery, and there were no significant differences in the patients' postoperative stress, wake, extubation, early postoperative pain scores and postoperative cognitive function. BIS values in 45-55 compared to 55-65 patients with low plasma cortisol levels may be associated with better control of stress levels, to maintain the BIS value between 45-55 anesthesia depths is more reasonable.展开更多
文摘Analysis of high resolution of aeromagnetic data was carried out over Lamurde, Adamawa state north-eastern Nigeria to determine the Curie point depth (CPD), heat flow and geothermal gradient. The aeromagnetic data used for this work was obtained at Nigerian geological survey agency, the total magnetic intensity was processed to produce the residual magnetic map which was divided into 4 overlapping blocks, each block was subjected to spectral analyses to obtain depths to the top boundary and centroid, while depth to bottom of the magnetic sources was calculated using empirical formula. The depths values obtained were then used to assess the CPD, heat flow and geothermal gradient in the area. The result shows that the CPD varies between 9.62 and 10.92 km with an average of 10.45 k, the heat flow varies between 150.73 and 132.78 mWm−20⋅°C−1 with an average of 139.12 mWm−20⋅°C−1 and the geothermal gradient in the study area varies between 12.16 and 15.67 °C/km with an average of 13.39 °C/km. In view of the above results, the high heat flow may be responsible for maturation of hydrocarbon in Benue Trough as well as responsible for the lead Zinc Mineralization. Again by implication, Lamurde area can be a good area for geothermal reservoir exploration for an alternative source for power generation.
文摘In some cases, if the insertion depth is shallower than expected, intramuscular (IM) injection of risperidone long-acting injectable (RLAI) may not penetrate the muscle fascia. However, if needle insertion depth is deeper than anticipated, needle penetration may cause damage to nerves, arteries and veins. Few clinical studies were done to evaluate the depth of needle length insertion reaching the intended gluteal muscle. The aim of this study was to evaluate the suitable depth of injecting RLAI. Twenty-six patients with schizophrenia were treated with RLAI, and randomly divided into two groups: 50 mm needle inserted group (Group-D, deep insertion, n = 13) and 20 mm needle insertion group (Group-S, shallow insertion, n = 13). For Group-S, the needle length was marked with a spacer at exactly 20 mm. Injections were performed by the psychiatrist or nurse, alternating between the two gluteal sites by double-cross method every two weeks. Clinical psychotic symptoms and injection site reactions were recorded throughout the study period. Experienced psychologists who were blinded from the needle-length experimental variable evaluated patients’ psychotic symptoms using the Positive and Negative Syndrome Scale (PANSS) every two weeks. The plasma 9-hydroxyrisperidone (9-OH-RIS) concentrations were measured every two weeks;comparison data were determined on the 8th week and the 14th week. No significant difference was observed in 9-OH-RIS concentrations, psychotic symptoms, injection site skin reactions of subjects in both groups. However, in Group-D, injection site adverse reactions were confirmed in two subjects (15%). In Group-S, injection site reactions were confirmed in six subjects (46%). Although effective 9-OH-RIS concentrations were obtained with the insertion using both depth, it was concluded that the 50 mm insertion length was more suitable for dorsogluteal IM injections in adult patients with schizophrenia as demonstrated by the incidence of local adverse skin reactions.
基金supported by the NASI Senior Scientist Fellowship project a DST research project (No. SR/S4/MS: 521/08)
文摘The problem of water wave scattering by a thin vertical elastic plate submerged in uniform finite depth water is investigated here.The boundary condition on the elastic plate is derived from the Bernoulli-Euler equation of motion satisfied by the plate.Using the Green’s function technique,from this boundary condition,the normal velocity of the plate is expressed in terms of the difference between the velocity potentials(unknown)across the plate.The two ends of the plate are either clamped or free.The reflection and transmission coefficients are obtained in terms of the integrals’involving combinations of the unknown velocity potential on the two sides of the plate,which satisfy three simultaneous integral equations and are solved numerically.These coefficients are computed numerically for various values of different parameters and depicted graphically against the wave number in a number of figures.
基金sponsored by the “Major Scientific and Technical Project of Science and Technology Department of Inner Mongolia in 2016 (Strong Earthquake Track in the Short Stage and Integration Innovation of Stereoscopic Observation Technology in Space and Ground)”
文摘We selected the 103 M_L≥2. 5 earthquake waveform data from the Inner Mongolia-Ningxia border during 2009-2015,which was recorded by the Inner Mongolia Digital Seismic Networks and used the simplex method, Hyposat method, double difference location method,and deterministic method (PTD) for the determination of focal depth,and compared the results. The CAP moment tensor inversion method is used to determine the focal depths of the Alxa Left Banner M5. 8 and M4. 2 earthquakes. The final results of the focal depth by the deterministic method (PTD) and the double difference location method fit well with the tectonic characteristics of the Inner Mongolia-Ningxia border area,but those of the simplex method and the Hyposat method do not. The average depth of the Inner Mongolia-Ningxia border seismic tectonic zone is 13. 32 ± 8 km.
基金financially supported by the Ministry of Education,Science Technology(MEST)and National Research Foundation of Korea(NRF)through the Human Resource Training Project for Regional Innovationby the development program of local science park funded by the ULSAN Metropolitan City and the MEST(Ministry of Education,Science and Technology)
文摘AA5454-O aluminum alloy plates with thicknesses of 1.4 and 1.0 mm were friction-stir-lap-welded (FSLWed).The influences of the tool plunge depth and welding distance on surface appearance,macrostructure and mechanical properties of the FSLWed plates were experimentally investigated.The tensile shear load of the FSLWed plates was compared with that of the adhesive-bonded plates.Defect-free FSLWed zones were successfully obtained in all the tool plunge depths and the welding distances.The FSLWed zones exhibited the relatively smooth surface morphologies.Under all the FSLWed conditions,the FSLWed zone exhibited higher average hardness than the base metal.In addition,the upper plate exhibited a higher average hardness than the lower plate,although there was no special tendency in spite of the change in the tool plunge depth and the welding distance.The maximum tensile shear load of the FSLWed plates was much higher than that of the adhesive-bonded aluminum alloy plate.Especially,under the FSLW condition of the plunge depth of 1.8 mm and the welding distance of 40 mm,the tensile shear load of the FSLWed plate reached a level about 41% greater than that of the adhesive-bonded aluminum alloy plate.In addition,the maximum tensile shear load of the FSLWed plate was increased with the increase of the welding distance.
文摘Recent studies have explored the relationship between aerosol optical depth (AOD) measurements by satellite sensors and concentrations of particulate matter with aerodynamic diameters less than 2.5 μm (PM2.5). However, relatively little is known about spatial and temporal patterns in this relationship across the contiguous United States. In this study, we investigated the relationship between US Environmental Protection Agency estimates of PM2.5 concentrations and Moderate Resolution Imaging Spectroradiometer (MODIS) AOD measurements provided by two NASA satellites (Terra and Aqua) across the contiguous United States during 2005. We found that the combined use of both satellite sensors provided more AOD coverage than the use of either satellite sensor alone, that the correlation between AOD measurements and PM2.5 concentrations varied substantially by geographic location, and that this correlation was stronger in the summer and fall than that in the winter and spring.
基金Supported by the National Natural Science Foundation of China(Nos.T2261149752,41976163,42476172)。
文摘Bathymetric measurement of shallow water is of fundamental importance to coastal environment research and resource management.However,there are still great challenges in estimating water depth using satellite observations in turbid coastal waters.In this paper,we developed a physicsenhanced deep neural network to estimate bathymetry of highly turbid waters of the Changjiang(Yangtze)River estuary from dual-polarized synthetic aperture radar(SAR)images.Sentinel-1A/B SAR images with a spatial resolution of 20 m×22 m were collected and matched with water depth data from nautical charts during 2017-2023.For the input parameters of the model,in addition to the normalized radar backscatter cross section(NRCS)at single polarization and incidence angle,the impacts of both polarimetric characteristics and physical environmental factors on model performance were discussed in detail.Results of feature importance analysis and sensitivity experiments indicate that the polarization ratio and NRCS after removing the influence of background sea surface wind field make significant contributions to the bathymetry retrieval model.The root mean square error(RMSE)of SAR derived water depth decreases from 1.44 to 0.78 m within 0-30-m depth,and the mean relative error(MRE)is reduced from 15.6%to 8.6%.Compared with other machine learning models such as ResNet,XGBoost,and Random Forest,the MRE is reduced by 3.9%,5.7%,and 7.4%,respectively.The spatial distribution of SAR derived water depth also exhibits a high degree of consistency with observations,demonstrating the great potential of the model in estimating the depth of turbid shallow waters.
文摘In this study,FLUENT software was employed to simulate the flow pattern and water depth changes in a 120° sharp bend at four discharge rates.To verify the numerical model,a 90° sharp bend was first modeled with a three-dimensional numerical model,and the results were compared with available experimental results.Based on the numerical model validation,a 120° bend was simulated.The results show that the rate of increase of the water depth at the cross-section located 40 cm before the bend,compared with the cross-sections located 40 cm and 80 cm after the bend,decreases with the increase of the normal water depth in the 120° curved channel.Moreover,with increasing normal water depth,the dimensionless water depth change decreases at all cross-sections.At the interior cross-sections of the bend,the transverse water depth slope of the inner half-width is always greater than that of the outer half-width of the channel.Hence,the water depth slope is nonlinear at each crosssection in sharp bends.Two equations reflecting the relationships between the maximum and minimum dimensionless water depths and the normal water depth throughout the channel were obtained.
文摘The presence of grassland biomes and species cannot be predicted by examining bottom up causes such as precipitation and temperature. Top down causes including herbivory and fire seem to be major controlling aspects with other factors secondary. We examined soil depth and competitive ability of two North American C4 grasses in a greenhouse experiment. Changes in dry mass were determined and competitive intensity was calculated for both species. Species were grown separately or together in pots 30, 90, or 180 cm deep. When grown in monoculture, Schizachyrium scoparium total and belowground dry mass increased from the 30 to 90 cm depth, with no further significant increase from 90 to 180 cm. Aboveground dry mass did not increase significantly with depth. Total dry mass of Buchloe dactyloides increased significantly with depth when grown in monoculture. Aboveground dry mass increased from 30 to 90 cm depth but not from 90 to 180 cm. Belowground dry mass of B. dactyloides did not increase significantly with depth. In 180 cm pots, 53% of S. scoparium root dry mass was in the top 30 cm;74% of B. dactyloides root dry mass was in the top 30 cm. Roots of B. dactyloides were not found deeper than 90 cm. Aboveground dry mass of S. scoparium was not different in mixture or monoculture at any depth. Buchloe dactyloides aboveground dry mass in mixture was significantly lower than monoculture at the 30 cm depth, but not at 90 or 180 cm. The greatest competitive intensity was in the shallow soil pots. Soil depth could partially explain mosaics found in C4 grasslands where both species were found together with S. scoparium on deeper soils and B. dactyloides on shallower soils.
基金supported by the Science Foundation of Aviation(No.2014ZE52055)the National Science Foundation of China(No.51675276)+1 种基金the Funding of Jiangsu Innovation Program for Graduate Education(No.KYLX_0231)the Fundamental Research Funds for the Central Universities
文摘The prediction of indentation depth of abrasive grain in hydrophilic fixed-abrasive(FA)lapping is crucial for controlling material removal rate and surface quality of the work-piece being machined.By applying the theory of contact mechanics,a theoretical model of the indentation depth of abrasive grain was developed and the relationships between indentation depth and properties of contact pairs and abrasive back-off were studied.Also,the average surface roughness(Ra)of lapped wafer was approximately calculated according to the obtained indentation depth.To verify the rationality of the proposed model,a series of lapping experiments on lithium niobate(LN)wafers were carried out,whose average surface roughness Ra was measured by atomic force microscope(AFM).The experimental results were coincided with the theoretical predictions,verifying the rationality of the proposed model.It is concluded that the indentation depth of the fixed abrasive was primarily affected by the applied load,wafer micro hardness and pad Young′s modulus and so on.Moreover,the larger the applied load,the more significant the back-off of the abrasive grain.The model established in this paper is helpful to the design of FA pad and its machining parameters,and the prediction of Ra as well.
基金supported by the National Natural Science Foundation of China(No.62103298)。
文摘Aiming at the problems of low detection accuracy and large model size of existing object detection algorithms applied to complex road scenes,an improved you only look once version 8(YOLOv8)object detection algorithm for infrared images,F-YOLOv8,is proposed.First,a spatial-to-depth network replaces the traditional backbone network's strided convolution or pooling layer.At the same time,it combines with the channel attention mechanism so that the neural network focuses on the channels with large weight values to better extract low-resolution image feature information;then an improved feature pyramid network of lightweight bidirectional feature pyramid network(L-BiFPN)is proposed,which can efficiently fuse features of different scales.In addition,a loss function of insertion of union based on the minimum point distance(MPDIoU)is introduced for bounding box regression,which obtains faster convergence speed and more accurate regression results.Experimental results on the FLIR dataset show that the improved algorithm can accurately detect infrared road targets in real time with 3%and 2.2%enhancement in mean average precision at 50%IoU(mAP50)and mean average precision at 50%—95%IoU(mAP50-95),respectively,and 38.1%,37.3%and 16.9%reduction in the number of model parameters,the model weight,and floating-point operations per second(FLOPs),respectively.To further demonstrate the detection capability of the improved algorithm,it is tested on the public dataset PASCAL VOC,and the results show that F-YOLO has excellent generalized detection performance.
基金supported by the National Natural Science Foundation of China(Grant Nos.12274313,62275184,and 62411540033)Collaborative Innovation Center of Suzhou Nano Science and Technology,Suzhou Basic Research Project(Grant No.SJC2023003)+1 种基金the Gusu Leading Talent Plan for Scientific and Technological Innovation and Entrepreneurship(Grant No.ZXL2024400)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Perfect anomalous reflections have been demonstrated in optical phase gradient metasurfaces(PGMs),but they suffer from single-frequency(narrow-band)response due to the intrinsic limitation of natural geometric periodicity.Here,we provide both numerical and analytical evidence that a depth gradient metasurface can achieve discrete ultra-broadband perfect anomalous reflection in the microwave range in the absence of geometric periodicity.Remarkably,by adjusting the operating frequency of the incident wave,the same effect can be steadily obtained via a physically equivalent phase periodicity in the PGM.Based on this mechanism,a perfect retroreflector with a broadband response ranging from 1 GHz to 40 GHz is realized.Our work has promising applications in communication,source tracking,and military satellites.
基金supported by the Natural Science Foundation of Jiangsu Province(Grant No.BK20170922)the Key Strategic Program of the Chinese Academy of Sciences,Water Ecological Security AssessmentGreat Strategy Research of Middle and Lower Yangtze River(Grant No.ZDRW-ZS-2017-3)
文摘Background: Foraging theory predicts that animals select patches that offer the highest net rate of energy gain. Hence, prey distribution patterns and spatiotemporal heterogeneity play important roles in determining animal feeding patch selection. For waterfowl foraging on buried aquatic plant tubers, the distribution and biomass of these plant organs vary with depth in the substrate. Since excavation costs also increase with depth, the energy intake of the animals foraging on these plants is highly sediment depth dependent. Methods: Here, using observations of Swan Geese (Anser cygnoides) foraging on Vallisneria natans tubers, we test our hypothesis that geese feeding on tubers buried at intermediate sediment depth maximize their daily energy intake because of the interaction between tuber size and abundance with depth. To do this, we measured the distribution patterns of buried Vallisneria tubers under both undisturbed conditions and post-exploitation by geese (i.e. giving-up conditions). We investigated the relationship between tuber size and burial depth, and total tuber biomass within each sediment layer in undisturbed and exploited plots. Finally, we compared modelled Swan Goose daily energy intake feeding on Vallisneria tubers buried at different sediment layers (1–10, 11–20 and 21–30 cm below the surface). Results: Dry weight of Vallisneria tubers linearly increased with burial depth, while average total dry weight density of tubers showed a unimodal relationship, peaking at intermediate levels. Not surprisingly, Swan Geese foraged most intensively on tubers buried at intermediate sediment depths, where they maximize their daily energy intake. Our results support our hypothesis that Swan Geese feeding on tubers at intermediate depths maximize their daily energy intake. Conclusions: Our study is the first to quantify foraging strategies of Swan Geese during the wintering period, emphasizing the importance of plant traits on foraging selection of belowground foragers.
文摘This paper outlines the application of the multi-layer perceptron artificial neural network (ANN), ordinary kriging (OK), and inverse distance weighting (IDW) models in the estimation of local scour depth around bridge piers. As part of this study, bridge piers were installed with bed sills at the bed of an experimental flume. Experimental tests were conducted under different flow conditions and varying distances between bridge pier and bed sill. The ANN, OK and IDW models were applied to the experimental data and it was shown that the artificial neural network model predicts local scour depth more accurately than the kriging and inverse distance weighting models. It was found that the ANN with two hidden layers was the optimum model to predict local scour depth. The results from the sixth test case showed that the ANN with one hidden layer and 17 hidden nodes was the best model to predict local scour depth. Whereas the results from the fifth test case found that the ANN with three hidden layers was the best model to predict local scour depth.
文摘For the issue of proppant embedment in hydraulic fracturing,a new calculation method of embedment depth considering elastic-plastic deformation was proposed based on the mechanism of proppant embedment into rocks by combining proppant embedment constitutive equations and contact stresses on the rock-proppant system.And factors affecting embedment depth of proppant were analyzed using the new method.Compared with the elastic embedment model,the results calculated by the new method match well with the experimental data,proving the new method is more reliable and more convenient to make theoretical calculation and analysis.The simulation results show the process of proppant embedment into rocks is mainly elastic-plastic.The embedment depth of monolayer proppants decreases with higher proppant concentration.Under multi-layer distribution conditions,increasing the proppant concentration will not change its embedment depth.The larger the proppant embedment ratio,the more the stress-bearing proppants,and the smaller the embedment depth will be.The embedment depth under higher closure stress is more remarkable.The embedment depth increased with the drawdown of fluid pressure in the fracture.Increasing proppant radius or the ratio of proppant Young’s modulus to rock Young’s modulus can reduce the proppant embedment depth.
文摘Concrete carbonation relates to the diffusion of CO2 inthe atmosphere through the concrete pores and to the dissolution of the hydrates. A great deal of uncertainty still remains in this subject as a result of the random nature of the infiltration of these aggressive agents as well as the material and structural properties of reinforced concrete. Consequently, in order to determine the degradation of these structures with time, it is necessary to approach the subject from a probabilistic point of view that it considers the uncertainties involved with the geometrical dimensions of these structures, with the material characteristics and with the environment and the subsequent deterioration that it provokes. The aim of this paper is the evaluation of carbonation depth (Xc) from a probabilistic analysis, focusing specifically on the study of the randomness of the most influential parameters on the reinforced concrete carbonation.
文摘AIM To clarify the diagnostic efficacy and limitations of endoscopic ultrasonography(EUS) and the characteristics of early gastric cancers(EGCs) that are indications for EUS-based assessment of cancer invasion depth.METHODS We retrospectively investigated the cases of 153 EGC patients who underwent conventional endoscopy(CE) and EUS(20 MHz) before treatment.RESULTS We found that 13.7% were "inconclusive" cases with low-quality EUS images, including all nine of the cases with protruded(0-I)-type EGCs. There was no significant difference in the diagnostic accuracybetween CE and EUS. Two significant independent risk factors for misdiagnosis by EUS were identified-ulcer scarring [UL(+); odds ratio(OR) = 4.49, P = 0.003] and non-indication criteria for endoscopic resection(ER)(OR = 3.02, P = 0.03). In the subgroup analysis, 23.1% of the differentiated-type cancers exhibiting SM massive invasion(SM2) invasion(submucosal invasion ≥ 500 μm) by CE were correctly diagnosed by EUS, and 23.1% of the undifferentiated-type EGCs meeting the expanded-indication criteria for ER were correctly diagnosed by EUS.CONCLUSION There is no need to perform EUS for UL(+) EGCs or 0-I-type EGCs, but EUS may enhance the pretreatment staging of differentiated-type EGCs with SM2 invasion without UL or undifferentiated-type EGCs revealed by CE as meeting the expanded-indication criteria for ER.
文摘Ejina rangeland is located in Alashan Laegue, west part of Innermongolian Autono-mous Region with a area of 1.22×10~4 square Km of which the available area is 6940 squareKm, Because the varieties of reasons, such as natural, human, historic and present, therunoff of Ejina River is decreased year by year, the irrigated area of the rangeland is de-creased. The deterioration of the ecologic environment is caused by the degeneration of
基金Sponsored by the Jiangsu Prospective Joint Research Project(Grant No.BY2016022-28)
文摘Recognition of the human actions by computer vision has become an active research area in recent years. Due to the speed and the high similarity of the actions, the current algorithms cannot get high recognition rate. A new recognition method of the human action is proposed with the multi-scale directed depth motion maps(MsdDMMs) and Log-Gabor filters. According to the difference between the speed and time order of an action, MsdDMMs is proposed under the energy framework. Meanwhile, Log-Gabor is utilized to describe the texture details of MsdDMMs for the motion characteristics. It can easily satisfy both the texture characterization and the visual features of human eye. Furthermore, the collaborative representation is employed as action recognition by the classification. Experimental results show that the proposed algorithm, which is applied in the MSRAction3 D dataset and MSRGesture3 D dataset, can achieve the accuracy of 95.79% and 96.43% respectively. It also has higher accuracy than the existing algorithms, such as super normal vector(SNV), hierarchical recurrent neural network(Hierarchical RNN).
文摘Objective:To observe the effects of different anesthesia depths on the level of plasma cortisol during operation and the score of postoperative MMSE in elderly patients underwent radical gastrectomy.Methods: A total of eighty seven elderly patients undergoing radical gastrectomy were enrolled in this study. Continuous infusion of propofol and remifentanil for anesthesia and maintenance of propofol were divided into two groups: BIS-I (BIS: 45-55) and BIS-II (BIS: 55-65) by adusting the doses of propofol. The data were recorded as following, thewhole dosage of propofol, the time of extubation and the score of VAS. The level of plasma cortisol was finished at the time of incision and tracheal intubation. MMSE scores were recorded on the day before operation and follow-up at 3 and 7 d postoperatively. Record the patient's operation to discharge time, postoperative complications.Results: The concentration of cortisol in BIS-I group was higher than that in BIS-II group. There was no significant difference in extubation time, extubation VAS score and MMSE score after operation.Conclusion:There were no significant differences in the BIS values between 45 and 65 for the elderly patients undergoing upper abdominal surgery, and there were no significant differences in the patients' postoperative stress, wake, extubation, early postoperative pain scores and postoperative cognitive function. BIS values in 45-55 compared to 55-65 patients with low plasma cortisol levels may be associated with better control of stress levels, to maintain the BIS value between 45-55 anesthesia depths is more reasonable.