HighlightsNozzle pressure drop varies between PWM systems at different application rates and application pressures.Change in flow rate with respect to the expected flow differs between PWM systems at different rates and pressures.There was a latency before the system reached the target application pressure.PWM systems operate for less time than the specified duty cycle, which may cause application errors.Abstract. Three PWM nozzle control systems, Capstan PinPoint II, John Deere ExactApply, and Raven Hawkeye, referred to as systems S1, S2, and S3, respectively, were used in this study. Data on nozzle pressure, boom pressure, flow rate, and response time were recorded with different duty cycles (25%, 50%, 75%, and 100%) and operating frequencies (10, 15, and 30 Hz) for two application rates (112.2 and 187.1 L ha-1) and two application pressures (275.8 and 448.2 kPa) at 1 kHz using a LabVIEW program and a cRIO data acquisition system. Results indicated that the PWM systems perform differently when operating at different application rates, pressures, duty cycles, and frequencies. Each PWM system provided a different pressure drop at the nozzle during operation. The increase in application rate and pressure increased the pressure drop. The percent change in flow rate with respect to the expected flow was also significantly different between the PWM systems, which could be due to the differences in pressure provided at the nozzle during operation. The PWM systems also showed latency before reaching the target application pressure during operation and operated for less time than the specified duty cycle at stable target pressure while also continuing to spray even after the solenoid valves had closed. The application pressure during peak and fall times and the time of stable application pressure within a cycle should be given careful consideration when selecting a PWM system, as they can contribute to application errors. Producers should also consider the pressure drop with the selected PWM system and target application rate to set up the system to apply at the desired pressure. Manufacturers mostly recommend operating PWM systems at 10 Hz. For the purpose of this study, the operating frequency of the PWM systems was set to 10 and 15 Hz for S1, to 15 and 30 Hz for S2, and to 10, 15, and 30 Hz for S3. Producers should expect differences in pressure drop, stabilized pressure application time, and flow rate if they choose to operate at a higher frequency. The results of this study are only applicable to the types of nozzle bodies and nozzle tips used. The data will differ based on the dual-orifice valve coefficient equation: the larger the second orifice, the greater the pressure drop. This will affect the final orifice pressure, as well as the flow rate. This study did not address the impact of flow resistance caused by differences in the design of nozzle bodies and nozzle types. Keywords: Nozzle flow rate, Pressure drop, Pulse width modulation control m
{"title":"Nozzle Flow Rate, Pressure Drop, and Response Time of Pulse Width Modulation (PWM) Nozzle Control Systems","authors":"J. Fabula, A. Sharda, Qing Kang, D. Flippo","doi":"10.13031/TRANS.14360","DOIUrl":"https://doi.org/10.13031/TRANS.14360","url":null,"abstract":"HighlightsNozzle pressure drop varies between PWM systems at different application rates and application pressures.Change in flow rate with respect to the expected flow differs between PWM systems at different rates and pressures.There was a latency before the system reached the target application pressure.PWM systems operate for less time than the specified duty cycle, which may cause application errors.Abstract. Three PWM nozzle control systems, Capstan PinPoint II, John Deere ExactApply, and Raven Hawkeye, referred to as systems S1, S2, and S3, respectively, were used in this study. Data on nozzle pressure, boom pressure, flow rate, and response time were recorded with different duty cycles (25%, 50%, 75%, and 100%) and operating frequencies (10, 15, and 30 Hz) for two application rates (112.2 and 187.1 L ha-1) and two application pressures (275.8 and 448.2 kPa) at 1 kHz using a LabVIEW program and a cRIO data acquisition system. Results indicated that the PWM systems perform differently when operating at different application rates, pressures, duty cycles, and frequencies. Each PWM system provided a different pressure drop at the nozzle during operation. The increase in application rate and pressure increased the pressure drop. The percent change in flow rate with respect to the expected flow was also significantly different between the PWM systems, which could be due to the differences in pressure provided at the nozzle during operation. The PWM systems also showed latency before reaching the target application pressure during operation and operated for less time than the specified duty cycle at stable target pressure while also continuing to spray even after the solenoid valves had closed. The application pressure during peak and fall times and the time of stable application pressure within a cycle should be given careful consideration when selecting a PWM system, as they can contribute to application errors. Producers should also consider the pressure drop with the selected PWM system and target application rate to set up the system to apply at the desired pressure. Manufacturers mostly recommend operating PWM systems at 10 Hz. For the purpose of this study, the operating frequency of the PWM systems was set to 10 and 15 Hz for S1, to 15 and 30 Hz for S2, and to 10, 15, and 30 Hz for S3. Producers should expect differences in pressure drop, stabilized pressure application time, and flow rate if they choose to operate at a higher frequency. The results of this study are only applicable to the types of nozzle bodies and nozzle tips used. The data will differ based on the dual-orifice valve coefficient equation: the larger the second orifice, the greater the pressure drop. This will affect the final orifice pressure, as well as the flow rate. This study did not address the impact of flow resistance caused by differences in the design of nozzle bodies and nozzle types. Keywords: Nozzle flow rate, Pressure drop, Pulse width modulation control m","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"13 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80655753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Leonard, H. Xin, B. Ramirez, John P. Stinn, Somak Dutta, Kai Liu, T. Brown-Brandl
HighlightsA calibration procedure was conducted using a Kinect V2 to convert image pixels to physical measurements.A total of 61 sows were observed, and their static and dynamic space usage was measured from depth images.Equations were developed to predict the length, width, and height of sow space usage.Abstract. The amount of space provided to individually housed sows has both financial and animal welfare implications. Many U.S. swine producers use stall dimensions based on recommendations published in the 1980s (length × width × height: 2.13 m × 0.61 m × 1.00 m). Limited empirical data are available concerning the space allocation needed to accommodate modern sows housed in stalls during breeding, gestation, or farrowing. This study used a time-of-flight depth sensor to quantify static and dynamic space usage of 61 modern sows in late gestation. A calibration equation was developed to convert image pixels to physical dimensions. Statistical models were developed to relate the length, width, and height of sow space usage to body weight. The dimensions of sow space usage were then predicted. Results showed that free choice space usage of average (228 kg) sows was 1.96 m × 1.15 m × 0.93 m (length × width × height). For 95th percentile (267 kg) sows, space usage was 2.04 m × 1.12 m × 0.95 m. The width of space usage was primarily attributed to sow body depth when lying recumbent and the dynamic space used for transitioning between postures. These results help to inform future gestating and farrowing sow housing designs. Further work is needed to understand how restrictions on sow space usage may impact sow welfare and production performance, as well as the space needed to perform behaviors such as defecating, feeding, and turning around. Keywords: Animal welfare, Computer vision, Farrowing stall, Gestation stall, Kinect V2, Space allowance.
HighlightsA校准程序使用Kinect V2将图像像素转换为物理测量值。共观察了61头母猪，并通过深度图像测量了它们的静态和动态空间使用情况。建立了预测母猪空间利用的长度、宽度和高度的方程。为单独饲养的母猪提供的空间数量涉及经济和动物福利。许多美国养猪户使用的猪舍尺寸是基于20世纪80年代发布的建议(长×宽×高:2.13米× 0.61米× 1.00米)。关于在繁殖、妊娠或分娩期间容纳现代母猪所需的空间分配，现有的经验数据有限。本研究使用飞行时间深度传感器对61头现代母猪妊娠后期的静态和动态空间利用进行了量化。建立了将图像像素转换为物理尺寸的校准方程。建立了母猪空间利用的长度、宽度和高度与体重之间的统计模型。然后对母猪空间利用的各维度进行了预测。结果表明，平均(228 kg)母猪自由选择空间利用率为1.96 m × 1.15 m × 0.93 m(长×宽×高)。对于第95百分位(267 kg)母猪，空间利用率为2.04 m × 1.12 m × 0.95 m。空间使用的宽度主要归因于母猪平卧时的身体深度和姿势之间转换所使用的动态空间。这些结果有助于为未来妊娠和分娩母猪的住房设计提供信息。对母猪空间使用的限制如何影响母猪的福利和生产性能，以及进行排便、进食和转身等行为所需的空间，需要进一步的工作来了解。关键词:动物福利，计算机视觉，产房，孕房，Kinect V2，空间补贴
{"title":"Static and Dynamic Space Usage of Late-Gestation Sows","authors":"S. Leonard, H. Xin, B. Ramirez, John P. Stinn, Somak Dutta, Kai Liu, T. Brown-Brandl","doi":"10.13031/TRANS.14002","DOIUrl":"https://doi.org/10.13031/TRANS.14002","url":null,"abstract":"HighlightsA calibration procedure was conducted using a Kinect V2 to convert image pixels to physical measurements.A total of 61 sows were observed, and their static and dynamic space usage was measured from depth images.Equations were developed to predict the length, width, and height of sow space usage.Abstract. The amount of space provided to individually housed sows has both financial and animal welfare implications. Many U.S. swine producers use stall dimensions based on recommendations published in the 1980s (length × width × height: 2.13 m × 0.61 m × 1.00 m). Limited empirical data are available concerning the space allocation needed to accommodate modern sows housed in stalls during breeding, gestation, or farrowing. This study used a time-of-flight depth sensor to quantify static and dynamic space usage of 61 modern sows in late gestation. A calibration equation was developed to convert image pixels to physical dimensions. Statistical models were developed to relate the length, width, and height of sow space usage to body weight. The dimensions of sow space usage were then predicted. Results showed that free choice space usage of average (228 kg) sows was 1.96 m × 1.15 m × 0.93 m (length × width × height). For 95th percentile (267 kg) sows, space usage was 2.04 m × 1.12 m × 0.95 m. The width of space usage was primarily attributed to sow body depth when lying recumbent and the dynamic space used for transitioning between postures. These results help to inform future gestating and farrowing sow housing designs. Further work is needed to understand how restrictions on sow space usage may impact sow welfare and production performance, as well as the space needed to perform behaviors such as defecating, feeding, and turning around. Keywords: Animal welfare, Computer vision, Farrowing stall, Gestation stall, Kinect V2, Space allowance.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"13 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85693941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Liao Juan, Wang Yao, Yin Junnan, Bi Lingling, Zhang Shun, Huiyu Zhou, Zhu Dequan
Highlights A GPS/INS/VNS integrated navigation system to improve navigation accuracy. An adaptive federal Kalman filter with the adaptive information distribution factor to fuse navigation information. Detection of seedling row lines based on sub-regional feature points clustering. A modified rice transplanter as an automatic navigation experimental platform. In this study, a global positioning system (GPS)/inertial navigation system (INS)/visual navigation system (VNS)-integrated navigation method based on an adaptive federal Kalman filter (KF) was presented to improve positioning accuracy for rice transplanter operating in paddy field. The proposed method used GPS/VNS to aid INS and reduce the influence of the accumulated error of the INS on navigation accuracy. An adaptive federal KF algorithm was designed to fuse navigation information from different sensors. The information distribution factor of each local filter was obtained adaptively on the basis of its own error covariance matrix. Computer simulation and the transplanter test were conducted to verify the proposed method. Results showed that the proposed method could provide accurate and reliable navigation information outputs, and achieve better navigation performance compared with that of single GPS navigation and integrated method based traditional federal KF.
{"title":"An Integrated Navigation Method Based on an Adaptive Federal Kalman Filter for a Rice Transplanter","authors":"Liao Juan, Wang Yao, Yin Junnan, Bi Lingling, Zhang Shun, Huiyu Zhou, Zhu Dequan","doi":"10.13031/TRANS.13682","DOIUrl":"https://doi.org/10.13031/TRANS.13682","url":null,"abstract":"Highlights A GPS/INS/VNS integrated navigation system to improve navigation accuracy. An adaptive federal Kalman filter with the adaptive information distribution factor to fuse navigation information. Detection of seedling row lines based on sub-regional feature points clustering. A modified rice transplanter as an automatic navigation experimental platform. In this study, a global positioning system (GPS)/inertial navigation system (INS)/visual navigation system (VNS)-integrated navigation method based on an adaptive federal Kalman filter (KF) was presented to improve positioning accuracy for rice transplanter operating in paddy field. The proposed method used GPS/VNS to aid INS and reduce the influence of the accumulated error of the INS on navigation accuracy. An adaptive federal KF algorithm was designed to fuse navigation information from different sensors. The information distribution factor of each local filter was obtained adaptively on the basis of its own error covariance matrix. Computer simulation and the transplanter test were conducted to verify the proposed method. Results showed that the proposed method could provide accurate and reliable navigation information outputs, and achieve better navigation performance compared with that of single GPS navigation and integrated method based traditional federal KF.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"43 1","pages":"389-399"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85768286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yangyang Guo, Yongliang Qiao, S. Sukkarieh, L. Chai, Dongjian He
HighlightsBiGRU-attention based cow behavior classification was proposed.Key spatial-temporal features were captured for behavior representation.BiGRU-attention achieved >82% classification accuracy on calf and adult cow datasets.The proposed method could be used for similar animal behavior classification.Abstract. Animal behavior consists of time series activities, which can reflect animals’ health and welfare status. Monitoring and classifying animal behavior facilitates management decisions to optimize animal performance, welfare, and environmental outcomes. In recent years, deep learning methods have been applied to monitor animal behavior worldwide. To achieve high behavior classification accuracy, a BiGRU-attention based method is proposed in this article to classify some common behaviors, such as exploring, feeding, grooming, standing, and walking. In our work, (1) Inception-V3 was first applied to extract convolutional neural network (CNN) features for each image frame in videos, (2) bidirectional gated recurrent unit (BiGRU) was used to further extract spatial-temporal features, (3) an attention mechanism was deployed to allocate weights to each of the extracted spatial-temporal features according to feature similarity, and (4) the weighted spatial-temporal features were fed to a Softmax layer for behavior classification. Experiments were conducted on two datasets (i.e., calf and adult cow), and the proposed method achieved 82.35% and 82.26% classification accuracy on the calf and adult cow datasets, respectively. In addition, in comparison with other methods, the proposed BiGRU-attention method outperformed long short-term memory (LSTM), bidirectional LSTM (BiLSTM), and BiGRU. Overall, the proposed BiGRU-attention method can capture key spatial-temporal features to significantly improve animal behavior classification, which is favorable for automatic behavior classification in precision livestock farming. Keywords: BiGRU, Cow behavior, Deep learning, LSTM, Precision livestock farming.
{"title":"BiGRU-Attention Based Cow Behavior Classification Using Video Data for Precision Livestock Farming","authors":"Yangyang Guo, Yongliang Qiao, S. Sukkarieh, L. Chai, Dongjian He","doi":"10.13031/trans.14658","DOIUrl":"https://doi.org/10.13031/trans.14658","url":null,"abstract":"HighlightsBiGRU-attention based cow behavior classification was proposed.Key spatial-temporal features were captured for behavior representation.BiGRU-attention achieved >82% classification accuracy on calf and adult cow datasets.The proposed method could be used for similar animal behavior classification.Abstract. Animal behavior consists of time series activities, which can reflect animals’ health and welfare status. Monitoring and classifying animal behavior facilitates management decisions to optimize animal performance, welfare, and environmental outcomes. In recent years, deep learning methods have been applied to monitor animal behavior worldwide. To achieve high behavior classification accuracy, a BiGRU-attention based method is proposed in this article to classify some common behaviors, such as exploring, feeding, grooming, standing, and walking. In our work, (1) Inception-V3 was first applied to extract convolutional neural network (CNN) features for each image frame in videos, (2) bidirectional gated recurrent unit (BiGRU) was used to further extract spatial-temporal features, (3) an attention mechanism was deployed to allocate weights to each of the extracted spatial-temporal features according to feature similarity, and (4) the weighted spatial-temporal features were fed to a Softmax layer for behavior classification. Experiments were conducted on two datasets (i.e., calf and adult cow), and the proposed method achieved 82.35% and 82.26% classification accuracy on the calf and adult cow datasets, respectively. In addition, in comparison with other methods, the proposed BiGRU-attention method outperformed long short-term memory (LSTM), bidirectional LSTM (BiLSTM), and BiGRU. Overall, the proposed BiGRU-attention method can capture key spatial-temporal features to significantly improve animal behavior classification, which is favorable for automatic behavior classification in precision livestock farming. Keywords: BiGRU, Cow behavior, Deep learning, LSTM, Precision livestock farming.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"178 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75446295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Cordeiro, P. Loro, Marcos R. C. Cordeiro, C. Sawka, K. Ominski, D. Flaten
HighlightsThe Manitoba Land Calculator is a tool to estimate land requirements for new and expanding livestock operations.This new tool reflects Manitoba production practices and recent advances in animal and crop performance.Considerably more land is needed for management of manure phosphorus than when only nitrogen is considered.Sufficient land for application of manure supports the environmental sustainability of livestock production.Abstract. The planning of new livestock and poultry facilities or expansion of existing facilities should ensure sufficient land for manure application. Decision support tools used to establish land requirements for manure nutrients should take into consideration advances in animal genetics, performance, feeding strategies, and available feeds. This article presents a new tool for estimating land requirements for new and expanding pig, beef, dairy, and poultry operations in the province of Manitoba, Canada. The Manitoba Land Calculator (MLC) estimates land requirements for manure nitrogen (N) and phosphorus (P). It uses a mass balance approach to estimate nutrient excretion by livestock and poultry based on typical Manitoba feeding practices, weight gain, and production cycles. Crop nutrient utilization and removals can be calculated for 20 common crops grown in Manitoba using reliable long-term yields and farm-specific crop areas. Two case studies (pig and poultry) were selected from the Livestock Technical Review Public Registry on the Government of Manitoba website to illustrate the inputs and outputs associated with the MLC. The results indicated that land requirements increased by 4.6-fold and 5.7-fold for the poultry and pig operations, respectively, compared to the previous provincial methodology due to the inclusion of P in the model. Securing additional land during the planning stages will support the implementation of nutrient stewardship principles that ensure the long-term environmental sustainability of livestock operations. Keywords: Animal production, Land requirements, Livestock and poultry, Manure, Mass balance, Nutrient excretion.
{"title":"The Manitoba Land Calculator: A Tool to Estimate Land Requirements for Manure Application in Manitoba, Canada","authors":"R. Cordeiro, P. Loro, Marcos R. C. Cordeiro, C. Sawka, K. Ominski, D. Flaten","doi":"10.13031/TRANS.14613","DOIUrl":"https://doi.org/10.13031/TRANS.14613","url":null,"abstract":"HighlightsThe Manitoba Land Calculator is a tool to estimate land requirements for new and expanding livestock operations.This new tool reflects Manitoba production practices and recent advances in animal and crop performance.Considerably more land is needed for management of manure phosphorus than when only nitrogen is considered.Sufficient land for application of manure supports the environmental sustainability of livestock production.Abstract. The planning of new livestock and poultry facilities or expansion of existing facilities should ensure sufficient land for manure application. Decision support tools used to establish land requirements for manure nutrients should take into consideration advances in animal genetics, performance, feeding strategies, and available feeds. This article presents a new tool for estimating land requirements for new and expanding pig, beef, dairy, and poultry operations in the province of Manitoba, Canada. The Manitoba Land Calculator (MLC) estimates land requirements for manure nitrogen (N) and phosphorus (P). It uses a mass balance approach to estimate nutrient excretion by livestock and poultry based on typical Manitoba feeding practices, weight gain, and production cycles. Crop nutrient utilization and removals can be calculated for 20 common crops grown in Manitoba using reliable long-term yields and farm-specific crop areas. Two case studies (pig and poultry) were selected from the Livestock Technical Review Public Registry on the Government of Manitoba website to illustrate the inputs and outputs associated with the MLC. The results indicated that land requirements increased by 4.6-fold and 5.7-fold for the poultry and pig operations, respectively, compared to the previous provincial methodology due to the inclusion of P in the model. Securing additional land during the planning stages will support the implementation of nutrient stewardship principles that ensure the long-term environmental sustainability of livestock operations. Keywords: Animal production, Land requirements, Livestock and poultry, Manure, Mass balance, Nutrient excretion.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"146 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76085642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Govenor, W. Hession, T. Keys, C. N. Jones, R. Stewart, L. Krometis
HighlightsNatural sediments labeled with rare earth elements can effectively be used as tracers for quantifying fine sediment transport and deposition.Two artificial floods in a small stream (100 ha watershed, 1.5 year return flow of 515 L s-1) transported fine sediment 0 m to >850 m at a maximum flow rate of 55 L s-1.Sediment deposition per unit area was greater in the channel than in the near-channel floodplain.Use of two distinct tracers demonstrated resuspension extent during sequential high-flow events.Presence of large wood in the channel was associated with reduced streamflow rate, decreased suspended sediment transport velocity, increased channel sediment deposition, and reduced near-floodplain sediment deposition.Abstract. Effective sediment management requires an understanding of the lag time between best management practice implementation and observable changes in the target water body. To improve our understanding of sediment lag times, we tested a method to label locally sourced sediments with rare earth elements to quantify fine sediment flow-through and storage in fluvial systems. We injected sediments labeled with lanthanum and ytterbium into a small stream during two artificial flood events. During the floods, we collected and quantified suspended sediments and sediment deposition in the stream channel and floodplain at four cross-sections within our study reach. Two down-gradient (90 m and 850 m) time-integrated suspended sediment samplers evaluated total travel distance. Sediment tracer observations of particle transport distances ranged from 0 m to at least 850 m at a maximum flow rate of 55 L s-1 (stream 1.5 year flow was 515 L s-1). Sediment deposition per unit area was greater in the channel than in the floodplain. The majority of sediment tracer mass injected into the stream entered storage within the first 69 m of the reach. Some particles that deposited following the first flood were resuspended and either transported downstream or redeposited within the study reach. Our results support the further use of rare earth elements as sediment tracers to inform water quality and sediment transport models, and to provide estimates of lag times between management actions and downstream improvements. Keywords: Fine sediment, Flood, Fluvial geomorphology, Lag time, Large wood, Rare earth elements, Sediment deposition, Sediment transport, Tracer.
用稀土元素标记的天然沉积物可以有效地作为示踪剂用于定量细沉积物的迁移和沉积。小流域(100 ha流域，1.5年回潮515 L s-1)两次人工洪水以55 L s-1的最大流量输沙0 ~ 850 m。河道内的单位面积泥沙淤积大于近河道洪泛平原。使用两种不同的示踪剂显示了连续高流量事件中的再悬浮程度。河道中大型木材的存在与河道流速降低、悬沙输运速度降低、河道泥沙淤积增加和近洪泛平原泥沙淤积减少有关。有效的沉积物管理需要了解最佳管理实践实施与目标水体可观察到的变化之间的滞后时间。为了提高我们对沉积物滞后时间的理解，我们测试了一种方法，用稀土元素标记当地来源的沉积物，以量化河流系统中细沉积物的流经和储存。我们在两次人工洪水期间向一条小溪注入了镧和镱标记的沉积物。在洪水期间，我们在研究范围内的四个断面上收集和量化了河道和洪泛区的悬浮沉积物和沉积物沉积。两个向下梯度(90米和850米)的时间积分悬浮沉积物采样器评估了总移动距离。在最大流量为55 L s-1时(河流1.5年流量为515 L s-1)，沉积物示踪观测颗粒输运距离在0 ~ 850 m之间。河道的单位面积泥沙淤积量大于河漫滩。注入河流的大部分沉积物示踪物质在河段的前69米内进入储存。在第一次洪水之后沉积的一些颗粒被重新悬浮起来，或者向下游输送，或者在研究范围内重新沉积。我们的研究结果支持进一步使用稀土元素作为沉积物示踪剂，为水质和沉积物运输模型提供信息，并提供管理行动与下游改善之间的滞后时间估计。关键词:细沙，洪水，河流地貌，滞后时间，大木材，稀土元素，泥沙沉积，泥沙运输，示踪剂
{"title":"Evaluating Rare Earth Elements as Tracers of Fluvial Processes: Fine Sediment Transport and Deposition in a Small Stream","authors":"H. Govenor, W. Hession, T. Keys, C. N. Jones, R. Stewart, L. Krometis","doi":"10.13031/TRANS.14358","DOIUrl":"https://doi.org/10.13031/TRANS.14358","url":null,"abstract":"HighlightsNatural sediments labeled with rare earth elements can effectively be used as tracers for quantifying fine sediment transport and deposition.Two artificial floods in a small stream (100 ha watershed, 1.5 year return flow of 515 L s-1) transported fine sediment 0 m to >850 m at a maximum flow rate of 55 L s-1.Sediment deposition per unit area was greater in the channel than in the near-channel floodplain.Use of two distinct tracers demonstrated resuspension extent during sequential high-flow events.Presence of large wood in the channel was associated with reduced streamflow rate, decreased suspended sediment transport velocity, increased channel sediment deposition, and reduced near-floodplain sediment deposition.Abstract. Effective sediment management requires an understanding of the lag time between best management practice implementation and observable changes in the target water body. To improve our understanding of sediment lag times, we tested a method to label locally sourced sediments with rare earth elements to quantify fine sediment flow-through and storage in fluvial systems. We injected sediments labeled with lanthanum and ytterbium into a small stream during two artificial flood events. During the floods, we collected and quantified suspended sediments and sediment deposition in the stream channel and floodplain at four cross-sections within our study reach. Two down-gradient (90 m and 850 m) time-integrated suspended sediment samplers evaluated total travel distance. Sediment tracer observations of particle transport distances ranged from 0 m to at least 850 m at a maximum flow rate of 55 L s-1 (stream 1.5 year flow was 515 L s-1). Sediment deposition per unit area was greater in the channel than in the floodplain. The majority of sediment tracer mass injected into the stream entered storage within the first 69 m of the reach. Some particles that deposited following the first flood were resuspended and either transported downstream or redeposited within the study reach. Our results support the further use of rare earth elements as sediment tracers to inform water quality and sediment transport models, and to provide estimates of lag times between management actions and downstream improvements. Keywords: Fine sediment, Flood, Fluvial geomorphology, Lag time, Large wood, Rare earth elements, Sediment deposition, Sediment transport, Tracer.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"71 1","pages":"905-918"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85885427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HighlightsUsing different nozzle sizes on a linear-move sprinkler irrigation system is a simple method for implementing VRI.This study established a variable-rate sprinkler irrigation model for a linear-move system with different nozzles.Uniformity parameters were predicted for different tests, and prediction accuracy ranged from 1.6% to 13.0%.The simulation model can be applied to other sprinkler systems with variable-rate irrigation.Abstract. Variable-rate irrigation (VRI) can vary the application rate by either changing the amount of water flowing through sprinkler nozzles (zone control) or varying the speed of a moving irrigation system across parts of a field, referred to as speed/sector control. The uniformity of sprinkler irrigation in each management zone under VRI directly affects crop growth and yield. The use of different nozzle diameters on a linear-move sprinkler irrigation system is a simple and affordable method for achieving VRI. There are few studies on modeling the uniformity of VRI on linear-move sprinkler irrigation systems. In this study, a cubic spline difference-value model was used to simulate the variable-rate water distribution and uniformity of a linear-move system. Nine tests were designed to evaluate VRI uniformity with different nozzle diameters. A simulation and corresponding field experiments were carried out. The application rate of the simulation model was higher than the experimental values because of wind drift. The uniformity coefficients of the simulation with nozzle diameters of 1.98, 2.97, and 4.17 mm in tests 1, 2, and 3 were 86.56%, 85.24%, and 79.94%, respectively. The uniformity coefficients of the VRI simulations with combinations of nozzle diameters in tests 4 through 9 were 76.89%, 80.70%, 76.67%, 69.58%, 76.64%, and 81.87%, respectively. The smallest error between the simulation and experiment was 1.6%, and the largest error was 13.0%. The simulation model and prediction method can be applied to other sprinkler irrigation systems. Keywords: Linear move, Simulation model, Sprinkler irrigation, Uniformity, VRI.
{"title":"Variable-Rate Irrigation Uniformity Model for Linear-Move Sprinkler Systems","authors":"Junping Liu, Umair Gull, D. Putnam, Isaya Kisekka","doi":"10.13031/trans.14313","DOIUrl":"https://doi.org/10.13031/trans.14313","url":null,"abstract":"HighlightsUsing different nozzle sizes on a linear-move sprinkler irrigation system is a simple method for implementing VRI.This study established a variable-rate sprinkler irrigation model for a linear-move system with different nozzles.Uniformity parameters were predicted for different tests, and prediction accuracy ranged from 1.6% to 13.0%.The simulation model can be applied to other sprinkler systems with variable-rate irrigation.Abstract. Variable-rate irrigation (VRI) can vary the application rate by either changing the amount of water flowing through sprinkler nozzles (zone control) or varying the speed of a moving irrigation system across parts of a field, referred to as speed/sector control. The uniformity of sprinkler irrigation in each management zone under VRI directly affects crop growth and yield. The use of different nozzle diameters on a linear-move sprinkler irrigation system is a simple and affordable method for achieving VRI. There are few studies on modeling the uniformity of VRI on linear-move sprinkler irrigation systems. In this study, a cubic spline difference-value model was used to simulate the variable-rate water distribution and uniformity of a linear-move system. Nine tests were designed to evaluate VRI uniformity with different nozzle diameters. A simulation and corresponding field experiments were carried out. The application rate of the simulation model was higher than the experimental values because of wind drift. The uniformity coefficients of the simulation with nozzle diameters of 1.98, 2.97, and 4.17 mm in tests 1, 2, and 3 were 86.56%, 85.24%, and 79.94%, respectively. The uniformity coefficients of the VRI simulations with combinations of nozzle diameters in tests 4 through 9 were 76.89%, 80.70%, 76.67%, 69.58%, 76.64%, and 81.87%, respectively. The smallest error between the simulation and experiment was 1.6%, and the largest error was 13.0%. The simulation model and prediction method can be applied to other sprinkler irrigation systems. Keywords: Linear move, Simulation model, Sprinkler irrigation, Uniformity, VRI.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"49 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84888532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Matthew V. Russell, A. Mittelstet, R. Joeckel, J. Korus, C. Castro-Bolinaga
HighlightsStabilization structures are only effective at stabilized segments.Erosion increased in two of the six segments in the post-stabilization period.Deposition decreased in all six segments in the post-stabilization period.Jetties are effective at reducing erosion but are also prone to fail.Abstract. The effectiveness of streambank stabilization structures is insufficiently quantified. Although such structures clearly reduce or eliminate streambank erosion at the local scale, little is known about associated effects on unstabilized reaches immediately upstream and downstream. This study measured streambank erosion and deposition in stretches of the Cedar River, 1.5 meander wavelengths upstream and downstream from 24 stabilization structures that included jetties, rock vanes, root wads, and gravel protection. We also measured erosion and deposition on the streambanks directly opposite the stabilized locations. We compared measurements from the pre-stabilization period (1993-2005) with those from the post-stabilization period (2005-2018) using historical imagery in ArcGIS. Upon completion of this analysis, we were able to reject an initial hypothesis that local and adjacent streambank segment erosion rates would be significantly less after stabilization, and that deposition rates would be greater in stabilized locations and adjacent stream segments. Instead, the differences in erosion from pre- to post-stabilization showed little or no statistical significance. Rather, our data indicated that streambank erosion decreased in only four of the six stream segments and was predominantly confined to the stabilized segment. Overall deposition decreased in all six stream segments after bank stabilization. In reaches where wooden jetties were installed, partial or total failure was common, and further increases in erosion and decreases in deposition were more pronounced. We conclude that streambank stabilization on the Cedar River is effective only at the location of installation; there is no measurable effect on adjacent unstabilized reaches. Our results demonstrate the need for improved streambank monitoring practices and better understanding of how streambank stabilization impacts an entire river system. Such advances will enhance stream restoration design and implementation, as well as support future river management efforts. Keywords: Adjacent stream reach, Deposition, Jetty, Erosion, Streambank stabilization.
{"title":"Impact of Bank Stabilization Structures on Upstream and Downstream Bank Mobilization at Cedar River, Nebraska","authors":"Matthew V. Russell, A. Mittelstet, R. Joeckel, J. Korus, C. Castro-Bolinaga","doi":"10.13031/trans.14551","DOIUrl":"https://doi.org/10.13031/trans.14551","url":null,"abstract":"HighlightsStabilization structures are only effective at stabilized segments.Erosion increased in two of the six segments in the post-stabilization period.Deposition decreased in all six segments in the post-stabilization period.Jetties are effective at reducing erosion but are also prone to fail.Abstract. The effectiveness of streambank stabilization structures is insufficiently quantified. Although such structures clearly reduce or eliminate streambank erosion at the local scale, little is known about associated effects on unstabilized reaches immediately upstream and downstream. This study measured streambank erosion and deposition in stretches of the Cedar River, 1.5 meander wavelengths upstream and downstream from 24 stabilization structures that included jetties, rock vanes, root wads, and gravel protection. We also measured erosion and deposition on the streambanks directly opposite the stabilized locations. We compared measurements from the pre-stabilization period (1993-2005) with those from the post-stabilization period (2005-2018) using historical imagery in ArcGIS. Upon completion of this analysis, we were able to reject an initial hypothesis that local and adjacent streambank segment erosion rates would be significantly less after stabilization, and that deposition rates would be greater in stabilized locations and adjacent stream segments. Instead, the differences in erosion from pre- to post-stabilization showed little or no statistical significance. Rather, our data indicated that streambank erosion decreased in only four of the six stream segments and was predominantly confined to the stabilized segment. Overall deposition decreased in all six stream segments after bank stabilization. In reaches where wooden jetties were installed, partial or total failure was common, and further increases in erosion and decreases in deposition were more pronounced. We conclude that streambank stabilization on the Cedar River is effective only at the location of installation; there is no measurable effect on adjacent unstabilized reaches. Our results demonstrate the need for improved streambank monitoring practices and better understanding of how streambank stabilization impacts an entire river system. Such advances will enhance stream restoration design and implementation, as well as support future river management efforts. Keywords: Adjacent stream reach, Deposition, Jetty, Erosion, Streambank stabilization.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"22 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85067855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qingzhu Zhang, Bing Li, Yunjie Xu, Jinbo Zhang, Mo Li, Jin Tong
HighlightsThe performance of biomimetic rollers was better than that of a conventional roller.The biomimetically ridged roller had better soil compaction performance.The resistance order of rollers with different materials was: Fe360A steel > UHMWPE > enamel coating.Packing force was the most significant factor.Abstract. To reduce soil adhesion and rolling resistance during seeding and improve the uniformity of plant spacing, a biomimetically ridged press roller (BRPR) and a biomimetically polyhedral press roller (BPPR) were designed. Moreover, hydrophobic materials, i.e., ultra-high molecular weight polyethylene (UHMWPE) and enamel coating, were applied and compared with uncoated Fe360A steel. Field experiments were conducted to test the effects of the biomimetic press roller type, material, velocity, and packing force on soil compaction characteristics. A conventional press roller (CPR) was used as a reference. Traction resistance (TR), soil bulk density (SBD), soil moisture content (SMC), emergence rate (ER), and percent change of plant spacing (PCPS) were measured. The packing force was the most significant factor affecting each index. For all rollers, the TR, SBD, ER, and PCPS increased with increasing packing force, while the loss of SMC decreased. The TR and SBD decreased with increasing velocity. All rollers achieved proper SBD for corn seeds. The biomimetic press rollers had a significant effect on TR, PCPS, and SMC on the third day after sowing. The BRPR had lower PCPS and TR than the BPPR and higher SMC than the BPPR on the third day after sowing. Compared with the CPR, the PCPS for all biomimetic rollers decreased, and the ER and SMC increased. The BPPR with Fe360A steel had a slightly higher TR than the CPR, but the other biomimetic rollers had a lower TR than the CPR. The BRPR decreased the TR by 2.13% to 22.30%, while the BPPR decreased the TR by 0.35% to 18.59%. Moreover, both types of biomimetic press rollers had the highest TR values when using Fe360A steel, followed by UHMWPE, and the enamel coating had the lowest TR values. The BRPR decreased the PCPS by 19.46% to 48.34%, while the BPPR decreased the PCPS by 9.69% to 36.99%. The biomimetic rollers increased the ER by 2.17% to 11.36%. On the 18th day after sowing, the SMC was 4.21% to 7.75% higher for the biomimetic press rollers compared to the CPR when the packing force was 700 N. This study can provide a reference for the biomimetic design, material, and force selection of press rollers. Keywords: Biomimetics, Compaction characteristics, Enamel coating, Press roller, UHMWPE.
{"title":"Effects of Biomimetic Press Roller Type, Material, Velocity, and Packing Force on Soil Compaction Characteristics","authors":"Qingzhu Zhang, Bing Li, Yunjie Xu, Jinbo Zhang, Mo Li, Jin Tong","doi":"10.13031/trans.14135","DOIUrl":"https://doi.org/10.13031/trans.14135","url":null,"abstract":"HighlightsThe performance of biomimetic rollers was better than that of a conventional roller.The biomimetically ridged roller had better soil compaction performance.The resistance order of rollers with different materials was: Fe360A steel > UHMWPE > enamel coating.Packing force was the most significant factor.Abstract. To reduce soil adhesion and rolling resistance during seeding and improve the uniformity of plant spacing, a biomimetically ridged press roller (BRPR) and a biomimetically polyhedral press roller (BPPR) were designed. Moreover, hydrophobic materials, i.e., ultra-high molecular weight polyethylene (UHMWPE) and enamel coating, were applied and compared with uncoated Fe360A steel. Field experiments were conducted to test the effects of the biomimetic press roller type, material, velocity, and packing force on soil compaction characteristics. A conventional press roller (CPR) was used as a reference. Traction resistance (TR), soil bulk density (SBD), soil moisture content (SMC), emergence rate (ER), and percent change of plant spacing (PCPS) were measured. The packing force was the most significant factor affecting each index. For all rollers, the TR, SBD, ER, and PCPS increased with increasing packing force, while the loss of SMC decreased. The TR and SBD decreased with increasing velocity. All rollers achieved proper SBD for corn seeds. The biomimetic press rollers had a significant effect on TR, PCPS, and SMC on the third day after sowing. The BRPR had lower PCPS and TR than the BPPR and higher SMC than the BPPR on the third day after sowing. Compared with the CPR, the PCPS for all biomimetic rollers decreased, and the ER and SMC increased. The BPPR with Fe360A steel had a slightly higher TR than the CPR, but the other biomimetic rollers had a lower TR than the CPR. The BRPR decreased the TR by 2.13% to 22.30%, while the BPPR decreased the TR by 0.35% to 18.59%. Moreover, both types of biomimetic press rollers had the highest TR values when using Fe360A steel, followed by UHMWPE, and the enamel coating had the lowest TR values. The BRPR decreased the PCPS by 19.46% to 48.34%, while the BPPR decreased the PCPS by 9.69% to 36.99%. The biomimetic rollers increased the ER by 2.17% to 11.36%. On the 18th day after sowing, the SMC was 4.21% to 7.75% higher for the biomimetic press rollers compared to the CPR when the packing force was 700 N. This study can provide a reference for the biomimetic design, material, and force selection of press rollers. Keywords: Biomimetics, Compaction characteristics, Enamel coating, Press roller, UHMWPE.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"11 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83436693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HighlightsA non-destructive prediction model for moisture content of wheat leaves was established based on electrical properties.The model based on a single property (capacitance or resistance) was improved by using both properties.The model accurately detected the moisture content of wheat leaves in real-time to avoid irrigation lag.The results provide a basis for real-time and targeted water-saving irrigation of winter wheat in an arid region.Abstract. In this study, we aimed to establish a non-destructive and rapid approach to monitor the moisture content of wheat leaves in Southern Xinjiang, China, and promptly acquire information on the physiological water demand of crops to guide precision irrigation. Wheat leaves were used as the research object. Using a custom-made clamped parallel-plate capacitor and LCR digital bridge meter, we determined the electrical properties (capacitance and resistance) of wheat leaves with various moisture contents within a frequency range from 0.12 to 100 kHz. Moreover, we explored the correlation between leaf moisture content and the electrical properties. Our data showed that leaf moisture exhibited the best correlation with the electrical properties at 50 kHz. Under these optimized conditions, a model for moisture measurement was established using a single-parameter method (capacitance or resistance). However, the estimated standard errors (RMSE) of this method were 3.29% (for resistance) and 3.49% (for capacitance), which were greater than the standard error of the measured moisture content (2%). Therefore, we developed an improved model using a two-parameter method (capacitance and resistance), and the estimated standard error was 2.68%, which was more feasible for predicting moisture content compared with the single-parameter method. The model was validated using eight groups of wheat leaf samples at the turning-green stage and the jointing stage, and the RMSE values were less than 2%. Our findings provide a scientific basis for real-time and targeted water-saving irrigation of wheat in arid areas of Southern Xinjiang. Keywords: Electrical property, Model, Moisture content, Precision irrigation, Wheat leaves.
{"title":"Electrical Properties Predict Wheat Leaf Moisture","authors":"Yumei Hao, Yuantao Hua, Xu Li, Xianqiang Gao, Ji-Ling Chen","doi":"10.13031/TRANS.14210","DOIUrl":"https://doi.org/10.13031/TRANS.14210","url":null,"abstract":"HighlightsA non-destructive prediction model for moisture content of wheat leaves was established based on electrical properties.The model based on a single property (capacitance or resistance) was improved by using both properties.The model accurately detected the moisture content of wheat leaves in real-time to avoid irrigation lag.The results provide a basis for real-time and targeted water-saving irrigation of winter wheat in an arid region.Abstract. In this study, we aimed to establish a non-destructive and rapid approach to monitor the moisture content of wheat leaves in Southern Xinjiang, China, and promptly acquire information on the physiological water demand of crops to guide precision irrigation. Wheat leaves were used as the research object. Using a custom-made clamped parallel-plate capacitor and LCR digital bridge meter, we determined the electrical properties (capacitance and resistance) of wheat leaves with various moisture contents within a frequency range from 0.12 to 100 kHz. Moreover, we explored the correlation between leaf moisture content and the electrical properties. Our data showed that leaf moisture exhibited the best correlation with the electrical properties at 50 kHz. Under these optimized conditions, a model for moisture measurement was established using a single-parameter method (capacitance or resistance). However, the estimated standard errors (RMSE) of this method were 3.29% (for resistance) and 3.49% (for capacitance), which were greater than the standard error of the measured moisture content (2%). Therefore, we developed an improved model using a two-parameter method (capacitance and resistance), and the estimated standard error was 2.68%, which was more feasible for predicting moisture content compared with the single-parameter method. The model was validated using eight groups of wheat leaf samples at the turning-green stage and the jointing stage, and the RMSE values were less than 2%. Our findings provide a scientific basis for real-time and targeted water-saving irrigation of wheat in arid areas of Southern Xinjiang. Keywords: Electrical property, Model, Moisture content, Precision irrigation, Wheat leaves.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"20 1","pages":"929-936"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82266477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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