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Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Adaption control strategy is a core technology as one part of control software for automatic transmission. The purpose of such strategy development is to compensate deviations due to engine torque signal difference, tolerance of transmission parts during manufacture, purchasing, storage and assembly processes, characteristics change with mileage accumulation, and to ensure acceptable shift quality and good drivability for the whole life of products. Many efforts have been made aimed to design self-learning strategies especially for dual-clutch automatic transmission and automated mechanical transmission by establishing vehicle launch strategy, feedback pressure control and solenoid duty cycle adjustment. While due to lack of pressure sensors in hydraulic automatic transmission, most of theories cannot be used directly. In overseas, main introductions on adaptive methods for upshift and downshift are published, but key technical information is strictly protected by corresponding patents and no detailed knowledge for instance control procedure is issued. According to different shift phases such as filling phase, torque phase and speeding phase, separated adaption methods like self-learning approach based on torque estimation or turbine acceleration signal are analyzed. But pressure sensor signal, longitudinal acceleration signal or high engine torque resolution are required for the application of those strategies, which seems not suitable for series transmission or low-level vehicles with domestic brands. To meet the requirements for TCU (transmission control unit) control software of vehicle production, adaption function for shifting clutches is researched, and corresponding software structure is introduced which includes shift type decision, shift quality monitoring, parameter adjustment and complicated method for adaption data update and storage. In addition, according to different profiles in torque phase and speeding phase for power on upshift and power on downshift, adaption strategies based on shifting time and turbine speed flare issue are proposed respectively. Then, according to shift sequence and shift control parameter of self-learning approach, complete software control procedures for parameter detection, processing, calculation and response are illustrated. It is very helpful for further research since parameter self-adjustment procedure turns to be clear with step by step introduction. A patent testing method is produced for recording shift issues, shift points, driving cycles and checking adaption results. The vehicle testing results showed that through adaption parameter adjustment, shifting time achieves to the target value, 700 ms, during power on upshift with only 2 repeated operations and for power on downshift, engine and turbine speed flare can be avoided gradually which makes shift quality better and more solid. The shift shock is reduced to 5 m/s3, which achieves to production vehicle shift quality level. The deviations due to the inconsistence of transmission from vehicle to vehicle and from engine to engine during manufacture and assembly process and characteristics deterioration can be compensated in very short time according to current research outcomes. [ABSTRACT FROM AUTHOR]

Spatial structure is an important characteristic of forest and spatial distribution pattern is one part of researches on population spatial behavior, Based on the relationship of neighborhood trees, three kinds of stand spatial structure parameters including uniform angle index, mingling and dominance was proposed by Professor Gangying Hui. In the past decade, stand spatial structure parameters are widely used to analyze stand spatial structure, calculate trees dominance, judge competition among trees, measure species diversity and recover or reconstruct stand structure at domestic and international study.. Measurement accuracy of spatial structural parameters (uniform angle index, mingling degree, and dominance) has a significant role in studying stand spatial structure. In the traditional direct interpretation method(DIM), it is difficult to measure the angle between reference tree and 4 nearest neighbor trees. For this method, the error derived from tree diameters at breast height is not considered in the process of measurement, so uniform angle index value is inaccurate. Moreover, based on DIM, other two parameters of mingle degree and dominance measurement required at least two operators, one person completed measurement and the other recorded field data, thus it is impossible to calculate the observing results immediately In this paper, a new measuring method named as HSSM was proposed using handheld smart station to measure stand spatial structure parameters in order to enhance measurement precision and accuracy, decrease field investigation workload. For measuring uniform angle index, the angle between reference tree and four nearest neighbor trees is not measured directly. Firstly, X-Y coordinates of reference tree and four nearest neighbor trees are measured using handheld smart station. Secondly, the diameters at breast height of five trees are measured corresponding with each tree, specifically, diameters at breast height measurement is to obtain center coordinates of five selected trees so as to increase angle calculation accuracy. Finally, reference tree as central point, intersection angles between four nearest neighbor trees are resolved according to the law of cosines. According to the above-mentioned measurement method, experiment was carried out in one stand forest plot (100 m×100 m) which located at Beijing Olympic Forest Park by three operators. The relative error of uniform angle index average value of HSSM was 2% less than that of DIM, average time-consuming (single person) of HSSM was 90.1s more than that of DIM (double person, 40.7 s), and measurement efficiency of HSSM was 8% lower than that of DIM. The mingle measurement result of HSSM were as the same as that of DIM, but the average time-consuming (single person) of HSSM was 21.5s less than that of DIM (double person, 32.2 s), measurement efficiency of HSSM was about 3 times that of DIM. The results of dominance relative error was 4% between HSSM and DIM, but the average time-consuming (single person) of HSSM was 74.8s more than that of DIM (31.05 s for double person), measurement efficiency of HSSM was 20% lower that of DIM. HSSM had the advantages of single person operation, display and storage directly by the equipment. Moreover, compared with the DIM, HSSM resolved the problem that DIM could not measure the tree center coordinate at breast height of reference tree and nearest neighbor tree, and for HSSM, the distribution of reference tree and nearest neighbor tree could draw conveniently and visually display according to measuring data in the process of interior work . This research can provide references for measuring forest spatial structure measurement accurately and efficiently. [ABSTRACT FROM AUTHOR]

Knotter is in the key position of the rectangular baler, and it's working quality is in direct relation to the job performance of the baler. D type knotter is now used more widely in the rectangular baler, and most of them used in domestic are imported from abroad. It is not only expensive but inconvenient in use and maintenance because of the complicated organization. Therefore, a new clip bale knotter was developed in order to develop independent intellectual property rights and meet the needs of the country. The paper was focused on analyzing the structures and working principles of D type knotter of rectangular baler and food packaging clipper machine to form a new kind of knotter. The main innovation of the new design was that the impacting clip action replaced the original knotting action of D type knotter through the U type clip punching device. To evaluate the knotter device, the architecture and working principles of the clip bale knotter were described and some experimental results of knotter applicability were verified. The clip bale knotter was composed of two parts. One part was based on the fan-shape dentate cam disc of D type knotter, for which the original knotter hook and corresponding meshing teeth of the fan-shape dentate cam disc were dismantled and the clipping rope and cutting rope organization were retained. The other part was added with U type clip punching device, U type clip feed mechanism and the driving machinery of punching. By designing U type clip punching device, driving mechanism of punching as well as U type clip feed mechanism, combining the calculation of the motion sketch of the cam swing rod mechanism, the integration of the clip bale knotter was finished. When the knotter worked, rope was sent to the above of the clipping rope disc by the sending rope needle powered by spindle, then the clipping rope disc was rotated to grip the rope, and the swing shaft of the knotter organization was made to swing by spindle cam through the deep-groove ball bearing. By the cooperation between U type clip feed mechanism and related artifacts of the punching device, U type clip was impacted to form a taut knot in the rope. In the process, the cutter swang to be just above the rope knot, and cutting the rope would end the knotting process. The driving machinery of punching and U type punching device moved back with the work of the swing shaft return spring and pushing rope plate respectively. To test the knotter's applicability, a bedstand was made. The knotting rate was used as the judgment standard. Three kinds of normal U type clips and 3 kinds of ropes were chosen to do the orthogonal experiments. The experimental results showed that when the spindle rotation speed was determined to be 90 r/min, it finished impacting clip within 0.7 s, and the rate of knotting and locking of the new knotter reached 99% and 100% respectively. During the experiment, delivering rope, clipping rope, impacting rope and cutting rope operated at an appropriate time sequence which ensured the knotting process to be finished. Compared with D type knotter, the new device had simpler structure, lower manufacturing difficulty and cost, and the operation and maintenance were more convenient. The results show that the knotter design is feasible and lays the foundation for further optimizing the structure and working parameters of the knotter and its evaluation. [ABSTRACT FROM AUTHOR]

Partial root-zone irrigation can stimulate the compensation effect of root water uptake at the irrigated zone. Plants can compensate for water stress in one part of the root zone by taking up water from other parts of the root zone where water is available. This study aimed to identify the dynamics and influencing factors of the compensation effect of maize roots (Zea mays L. hybrid cv. Aoyu No. 3007) under partial root zone irrigation. With the split-root technology, we conducted a hydroponic experiment to analyze the root zone water stress that was simulated by the osmotic potential of a nutrient solution (PEG-6000). There were 3 water stress levels, −0.2 (mild water stress), −0.4, −0.6 MPa (moderate water stress), and a control treatment (control, both sides of the root zone supplied with sufficient water). The root growth and hydraulic conductance of each root zone were measured at 0, 0.25, 0.5, 1, 3, 5, 7 and 9 d after the experiment started. Within 0.25 d after the experiment start, the total hydraulic conductance and the hydraulic conductance per root length between the two root zones in all three treatments and control were not significantly different (P>0.05) if the water stress was less than −0.6 MPa. When the partial water stress lasted more than 0.25 d, the total hydraulic conductance and the hydraulic conductance per root length in stressed root zone were lower (P<0.05) than that in the non-stressed root zone. Compared with non-stressed root zone, the reduction rate of root hydraulic conductance in the stressed root zone was significantly (P<0.05) increased with the increase in partial water stress degree and duration. At five days, compared to the root hydraulic conductance per root length in the non-stressed root zone, the corresponding value in the stressed root zone for the treatments −0.2, −0.4 and −0.6 MPa decreased by 32.70%, 49.90% and 50.97%, respectively. Within 0.25 d after the experiment start, for the treatment −0.4 and −0.6 MPa, the total hydraulic conductance in the stressed root zone reduced by 20% and 30% compare with the treatment −0.2 MPa. Twelve hours after the experiment start, the hydraulic conductance per root length in the non-stressed root zone for the treatment −0.2 MPa increased by 10.11% compared to control, and recovered to control level after 1 d. On the ninth day, the hydraulic conductance per root length in the non-stress root zone for the treatment −0.4 MPa (25.08×10-11 m2/(MPa·s)) was significantly greater (P<0.05) than that for control, indicating this treatment had an obvious compensation effect on root water uptake. However, the corresponding value for the treatment −0.6 MPa reduced by 19.05%-40.11% after 0.5 d, which recovered to the level of control after 5 d. The results indicated that the compensation effect of root water uptake in the non-stress zone can be effectively stimulated. The compensation effect started to occur at 0.5 d after the experiment start and was affected by the degree and duration of the water stress. −0.4 MPa was the threshold of partial root zone water stress for effectively stimulating compensatory effect of root water absorption in non-stressed root zone. [ABSTRACT FROM AUTHOR]

Studying the variation of fruit and stem diameter is critical for optimizing irrigation schedule of tomato under alternate partial root zone drip irrigation (APRI) and improving water use efficiency in the green house. A plant physiology monitoring system (LPS-05MD) was used to measure the variation of fruit diameter and stem diameter during the fruiting stage of tomato under three different irrigation regimes: conventional drip irrigation (CDI), APRI and fixed partial root-zone irrigation (FDI). The soil under CDI were irrigated to 100% field capacity (FC) of the root-zones (from 0 m to a maximum depth of 0.40 m during the fruiting stage) by the drip irrigation system when the soil water content (SWC) in the root-zone reaching 80% FC. During the same day, the APRI and FDI treatments received about 2/3 of the irrigation amount for CDI, but only irrigated to one part of the root-zones (approximately 1/2 of the whole root-zone). For APRI, the irrigated root zone was alternatively changed from one side to another and consequently resulted in the SWC of different sides alternately high and low; whereas in FDI treatment, only the fixed side was irrigated and the other side was kept drying during the growing season. Results indicated that the variation of fruit diameter was significantly higher (P<0.05) in sunny days with high solar radiation rate than that of cloudy day with low solar radiation rate. The increase of tomato fruit diameter per day was not significantly linearly related to average SWC of the whole root zone (R²=0.30, P=0.16), but significantly related to the average solar radiation rate (R²=0.64, P=0.018). Previous studies indicate that the magnitude of MDS (maximum daily stem shrinkage) are not constant over a period of days with the same water status but different environmental conditions, and absolute MDS values registered without considering the evaporative demand might be meaningless. Based on this, there was a positive linear relationship between MDS and ET0 (R²=0.38, P<0.001), and the relationship between the value of MDS divided by ET0 (MDS/ET0) with SWC was significant different than MDS with SWC, which indicated that normalizing the absolute MDS values by environmental parameters, such as ET0, can help to indicate the soil water status precisely. Contrary to the previous results that MDS values increase in response to drought stress, in this study, MDS of APRI decreased with increasing water stress. This might be explained by the low resistance of water flow and high hydraulic capacitance of the tomato cultivar as well as the special physiological responses under APRI. For APRI, MDS/ET0 had a close relationships with SWC in the drying and wet root-zone (R²=0.60, P=0.006 and R² =0.88, P<0.001, respectively), which indicated that MDS normalized by ET0 under APRI was influenced both by SWC of drying side and wet side, and predominantly by the irrigated root-zone. Similarly, MDS/ET0 in FDI treatment was closely linearly related with the SWC in the irrigated root-zone (R²=0.61, P<0.001), but not with the fixed drying side (R²=0.02, P=0.64). This phenomenon can be explained by the decay of roots in the drying root-zone and the diminishment of the chemical signal generated from the drying roots of FDI. To the best of our knowledge, no study has been done to investigate the relationship between MDS (or MDS/ET0) and SWC of different root zone under APRI. The data in this study can help to reveal the mechanisms of variation of fruit diameter and stem diameter, as well as providing useful information for optimizing irrigation schedule of tomato under APRI grown in greenhouse. [ABSTRACT FROM AUTHOR]