Flat Trajectory Research Articles

The heterogeneity of intimate partner violence and its associations with distressed couples' emotional communication.

To understand the ways in which heterogeneous aspects of intimate partner violence (IPV) differentially influence partners' emotional expression during the conflict, the present study examined the unique and interactive effects among (a) types of IPV (psychological and/or physical), (b) directionality of IPV (unilateral or bilateral), and (c) couples' conversation topic (initiated by men or women) on the trajectories of emotional arousal in distressed, different-gender couples (N = 106). Vocally encoded emotional arousal (f₀) was measured during couples' recorded conversations. Findings from growth-curve analyses demonstrated that the level of IPV, directionality of IPV, and conversation topic were associated with different patterns of emotional arousal. First, during the discussion of the woman's topic, escalation was observed among recipients of violence in relationships with high levels of unilateral IPV, while their partners-that is, perpetrators of IPV-demonstrated stable, flat trajectories. Second, during men's conversations, stable levels of arousal were predominantly observed among both partners in relationships with men's unilateral IPV and with bilateral psychological and physical IPV. Finally, for partners who engaged in low levels of IPV, men and women both showed escalating arousal across women's conversations; however, when discussing the man's topic, they demonstrated different patterns, with men escalating linearly and women maintaining stable levels of arousal. These findings converge to suggest a picture in which distressed partners who either engage in or experience IPV use "all-or-nothing" approaches to emotional expression during conflict-not only escalating but also containing or controlling their emotional arousal across various contexts. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Application of the Lambert function in the analytical solution of ballistics problems for flat flight trajectories of a material body, taking into account the gaseous (air) medium

Annotation. The paper describes the use of a special Lambert function for solving problems of ballistics of a material body, when the resistance of a gaseous (air) medium is taken into account. A model of quadratic (based on the speed of movement of a body) resistance of the medium within the limits of an approaching flat trajectory is considered. Problem. Problems of ballistics of a material body are considered in courses of theoretical mechanics, as well as in specialized literature. But, in addition to the cited literature, this research, like, for unraveling the simplified level of the material body in the problems of ballistics for flat trajectories of the power of a special function Lambert, which allows us to essentially simplify the algorithm for developing the parameters of the trajectory of a gentle slope (floor) type. Goal. The goal of the work is based on a framed model of a material body for flat trajectories in problems of modern ballistics on this basis, using a special Lambert function, to be controlled by a visible decoupling Didion, the determination of the main parameters of these types of crash trajectories. Methodology. Physic, mechanical and mathematical models are constructed that adequately describe the parameters of the collapse of a material body/particle that collapses along a flat trajectory when the wind is not supported , which are proportional to the square of the fluidity of the particles. For a more manual description of the parameters of the trajectory of the motion, there is a special Lambert function, which is tabulated in [1], or can be expanded with the help of computer in the middle of “Maple 8”. Practical value. The results obtained in the work can be used to improve and clarify engineering methods of calculation in problems of external ballistics of a material body, taking into account the quadratic (in terms of movement speed) resistance of the air environment

Mapping structured Laguerre–Gaussian beam states onto the orbital Poincaré sphere in the form of controllable spatial trajectories

The structured Laguerre–Gaussian (LG) beam is a two-parameter superposition of 2n+ℓ+1 Hermite–Gaussian modes (where n and ℓ are a radial number and a topological charge of the initial LG beam) whose orbital angular momentum oscillations are controlled by phases and amplitude parameters. But we succeeded in reducing its representation to a simple sum of a standard LG mode and a hybrid Hermite–Laguerre–Gaussian (HLG) beam that is a key point in understanding a hidden geometry of the structured LG (sLG) beams and implementations of its unique prosperities. In assents, the hybrid HLG beam is mapped onto the orbital Poincaré sphere in the form of a plane trajectory along a main meridian of the sphere. However, the most intriguing thing is as follows. First, once we slightly perturb the HLG beam with a single LG mode, the flat trajectory turns into a complex multi-petalled tracery with multiple self-intersections due to cyclic variation of the phase parameter of the sLG beam. Moreover, the shape of the tracery as well as the birth and destruction of the self-intersection points can be controlled with the amplitude parameter. However, it is worth noting that when changing the beam parameters cyclically, the area outlined by the trajectory on the sphere is directly related to the geometric phase acquired by the sLG beam that can be treated as an additional degree of freedom for transmitting big data. In the article, we study the sLG beam properties and its mapping onto the orbital Poincarè sphere in the framework of a symplectic 4×4 matrix formalism while the orbital Stokes parameters are experimentally measured, and we have found good agreement between theory and experiment.

Profits and capital accumulation in the Mexican economy

Abstract The paper studies the long-run disconnection between a rising profit share of income and a constant rate of capital accumulation in Mexico since the early 1990s. According to stylized facts based on the Cambridge accumulation equation, the disconnection reflects two factors: first, a flat trajectory of the investment share of profits, and second, a gap between a rising profit share and a constant or even falling profit rate due to a decline in the output/capital ratio. In manufacturing—where the disconnection was particularly sharp—econometric estimates show that the accumulation rate was negatively affected not only by the decline in the output/capital ratio but also by a fall in the relative Mexican/US profit rate. The estimates show in addition that, among financialization indicators, a rise in interest payments as a share of profits may have contributed to the low accumulation rate.

Weight trajectories and obesity remission among school-aged children.

Many studies examining weight trajectories have used adiposity measures shown to be problematic for trajectory analysis in children with obesity, and remission of obesity remains poorly understood. To describe weight trajectories for school-aged children, the rate of obesity remission and factors associated. Children between 6 and 11 years of age with ≥3 valid height and weight measurements from an Oregon hospital-system over a minimum six-month period were included. Percent distance from the median body mass index (BMI) was used for modeling. Latent class analysis and linear mixed models were used to classify children based on their weight trajectory. We included 11,247 subjects with a median of 2.1 years of follow-up, with 1,614 (14.4%) classified as overweight and 1,794 (16.0%) classified as obese. Of subjects with obesity, 1% experienced remission during follow-up, whereas 23% of those with overweight moved to within a healthy weight range. Latent class analysis identified three classes within each weight-based stratum over time. The majority of children with overweight or obesity had a flat trajectory over time. Lower socioeconomic status was associated with a worsening trajectory. Latent class models using alternate measures (BMI, BMI z-scores, tri-ponderal mass index (TMI)) differed substantially from each other. Obesity remission was uncommon using the adiposity metric of distance from the median though transition from overweight to healthy weight was more common. Children with low socioeconomic status have worse trajectories overall. The choice of adiposity metric may have a substantial effect on the outcomes.

RST Switching Bi-controller Based Flatness for an Electronic Throttle Valve

In this paper, an RST switching bi-controller, based on flatness and on Luenberger observers, is designed to control the opening angle change of an Electronic Throttle Valve (ETV), to compensate unexpected external disturbances and to detect sensor faults. Two identified mathematical linear models are established to simulate the ETV for two different positions of the throttle plate. The use of robust RST switching bi-controller based-flatness approach by the development of closedloop control is proposed, in order to obtain a stable system tracking a desired flat trajectory. The switching between the two models using stateflow tool is based on residual values generated by using the Luenberger observers in order to detect and to localize sensor faults occurrence. The observer’s gains are determined using Linear Matrix Inequalities (LMIs) taking into account the stability of the system based on Lyapunov theory. The simulation results show the efficiency of the developed robust switching RST bi-controller based-flatness in terms of tracking the desired angle’s reference trajectory, rejecting disturbances and detecting sensor faults.

Similarities and Differences in the Longitudinal Trajectories of Depressive Symptoms from Mid-Adolescence to Young Adulthood: the Intersectionality of Gender, Race/Ethnicity, and Levels of Depressive Symptoms.

Understanding similarities and differences between groups with intersecting social identities provides key information in research and practice to promote well-being. Building on the intersectionality literature indicating significant gender and racial/ethnic differences in depressive symptoms, the present study used quantile regression to systematically present the diversity in the development of depressive symptoms for individuals with intersecting gender, race/ethnicity, and levels of symptoms. Information from the National Longitudinal Survey of Youth 79: Child and Young Adult study was employed. A detailed picture of depressive symptom trajectories from low to high quantiles was illustrated by depicting 13 quantile-specific trajectories using follow-up data from ages 15 to 40 in six gender-race/ethnicity groups: both genders of Black, Hispanic, and non-Black, non-Hispanic individuals. From low to high quantiles, Black and non-Black, non-Hispanic individuals showed mostly curved, and Hispanic individuals showed mostly flat trajectories. Across the six gender-race/ethnicity groups, the trajectories below 0.50 quantiles were similar in levels and shapes from mid-adolescence to young adulthood. The differences between the six gender-race/ethnicity groups widened, indicated by outspreading trajectories, especially at quantiles above 0.50. Furthermore, non-Black, non-Hispanic males and females showed especially fast-increasing patterns at quantiles above 0.75. Among those without or with only a high school degree, Black females and non-Black, non-Hispanic females tended to report similar levels of depressive symptoms higher than other groups at high quantiles. These unique longitudinal trajectory profiles cannot be captured by the mean trajectories. The intersectionality of gender, race/ethnicity, and quantile of symptoms on the development of depressive symptoms was identified. Further studying the mechanism explaining this diversity can help reduce mental health disparities.

Planning the Trajectory of a Collaborative Robot for Bioprinting

In situ bioprinting is an automated process of direct application of biomaterials to a defective area of living tissue during a medical operation. To perform such bioprinting, it is advisable to use robotic manipulators with five or more degrees of mobility, which can give the end effector the desired orientation. The actual task is to plan the trajectory of the robot for in situ bioprinting on a real curved surface. A brief analysis of solutions allowing to plan the trajectory of bioprinting is carried out. A mathematical description of the surface used as a defect model is given, which is necessary for constructing the trajectory. Additional restrictions were introduced in order to reduce the complexity of the scheduling algorithm. To localize a defect on a curved surface, information about a given contour covering this defect is used. An algorithm has been developed for forming a flat trajectory of the robot’s end effector to fill in the defect, followed by projecting it onto a real curved surface. The importance of preprocessing data on the scanned surface using the developed filtering algorithm based on the moving average method is noted. The trajectory of the robot’s end effector is formed by layers first in the plane. It is then projected onto a curved surface. For each point of the trajectory, such a homogeneous transformation matrix is calculated so that the robot’s end effector is perpendicular to the curved surface. The calculation of the orientation angles of the working body of the KUKA robot is presented on the basis of data obtained from a homogeneous transformation matrix. The operability of the proposed trajectory planning algorithm for in situ bioprinting is confirmed by the results of computer modeling using the software developed by the authors and the results of an experimental study of bioprinting performed by the KUKA LBR R820 collaborative robot on three samples with different surface curvature and defect contour

Maternal prenatal cortisol trajectories predict accelerated growth in infancy

Higher maternal cortisol in pregnancy has been linked to childhood obesity. Much of the previous research has been limited in that cortisol in pregnancy is only measured at one time-point, precluding the ability to examine critical timing effects of prenatal maternal cortisol. To fill this gap, this longitudinal study measured maternal plasma cortisol at 15, 19, 25, and 31 weeks of pregnancy, and assessed infant body mass index percentile (BMIP)11Body mass index percentile. at birth, 3, 6, 12, and 24 months in 189 mother-infant pairs. Three distinct patterns of maternal cortisol in pregnancy (typical, steep, and flat trajectories) were identified using general growth mixture modeling (GGMM)22General growth mixture modeling. and then used to predict child growth patterns using multilevel modeling. Infants of mothers who had flat cortisol trajectories, characterized by relatively high cortisol in early gestation that plateaus by mid-gestation, experienced more rapid increases in BMIP from birth to 6 months, and had higher BMIPs at 3 and 6 months, than infants whose mothers had the typical slow cortisol rise over gestation, or steep (rapidly accelerating) trajectories. These results suggest that it is not just the total amount of maternal cortisol in pregnancy that shapes early infant growth, but instead the timing and trajectory of prenatal cortisol exposure. To better understand the early origins of obesity risk, future research is needed to investigate the factors that shape mothers’ prenatal cortisol trajectories.

Differences of sedimentary triggers and depositional architecture of lacustrine turbidites from normal regression to forced regression: Eocene Dongying depression, Bohai Bay Basin, East China

Sedimentary processes of marine turbidite systems under sea-level changes have been the focus of deep-water sedimentology. Compared with well-studied marine basins, the products of deep-water sediment gravity flows responding to lake-level changes in closed lacustrine basins are still poorly understood. In this study, we integrate cores of 10 exploratory wells, logs of 280 development wells, 3D seismic data and geochemical elements from the Eocene Dongying Depression, Bohai Bay Basin, East China to investigate sedimentary mechanisms and depositional architecture of lacustrine turbidite systems under lake-level changes. The studied strata are divided into three parasequence sets (PSS4 ~ PSS2), corresponding to early highstand normal regression with ascending trajectories, late highstand normal regression with flat trajectories, and forced regression with descending trajectories, respectively. From early highstand normal regression to forced regression, the ratios of Fe/Mn and U/Th reveal that the humid climate shifted to the arid climate. More lithofacies clues indicate that turbidites in highstand normal regression were triggered by river floods, whereas counterparts in forced regression were related to sediment failures. There are different architectural features of turbidite systems in three regression stages. PSS4 developed a series of channel belts within which individual channel elements are aggraded vertically. PSS3 is composed of a channelized lobe formed by individual distributary channels migrating laterally. PSS2 is characterized by a suite of compensational stacking debrite tongues. Climate forcing is a crucial factor controlling depositional architecture of the turbidite systems. A relatively humid climate during highstand normal regression led to rising lake-level and frequent floods, which are conducive to the formation of hyperpycnal-fed channel-lobe systems. Nevertheless, during forced regression under an arid climate, the strong progradational clinothems were prone to failure and sediment remobilization, resulting in debrite tongue complexes. This study highlights depositional differences of lacustrine turbidites during regression stages under the control of climate. Meanwhile, it also provides a new predictive model for deep-water hydrocarbon exploration and production in lacustrine basins worldwide.

PHENOMENOLOGICAL CRITERIA OF DESTRUCTION

The paper reviews the known deformability criteria, which have become widespread to assess the probability of failure in both monotonic and nonmonotonic plastic deformation. The most widely used methods of assessing plasticity, in which the dependence of plasticity on the stress state scheme is described by plasticity diagrams. The plasticity diagram is an experimental dependence of the ultimate deformation on the stiffness index of the stress state. In most works, this dependence is represented by a flat curve. The plasticity of metals depends on many factors, namely the nature of the metal and the thermomechanical parameters of the process. With cold plastic deformation, the main factor influencing plasticity is the stress state and the law of its change during loading. To quantify the impact of stress state on the probability of failure using failure criteria. Under the destruction is understood the appearance of macrocracks, which leads to irreparable damage to the product. A common disadvantage of the known deformation criteria, which are common to assess the probability of failure in both monotonic and nonmonotonic plastic deformation is that the subintegral functions of these criteria are based on the hypothesis that the effect of stress state on plasticity is described by the plasticity diagram and the influence of load history – flat trajectories. Due to the fact that the plasticity diagrams cover a rather narrow class of stress states, in applied theories of deformability there is no single approach to estimating the value of the used plasticity resource in the processes of metal forming. From the performed research it follows that at present there are almost very few works in which the dependence of plasticity on the history of loading is described by spatial trajectories. Therefore, the question of the destruction criteria remains open and relevant.

Trajectories of Self-Esteem Development for Adolescence Based on China Family Panel Studies: A Piecewise Growth Mixture Model Analysis

Self-esteem has always been a hot research object in the field of adolescent mental health. But in longitudinal research, using a single slope to describe the trajectory of adolescent self-esteem is unrealistic. The piecewise growth mixture model (PGMM) was used to fit the data in this study. Selecting from China Family Panel Studies database, a total of 1,759 individuals were selected and their self-esteem (RSES) scores over the years were used as the tracking index. Based on the characteristics of the development trajectories of three latent classes, class 1 was referred to as “stable low level group,” class 2 was named “rapidly rising group,” and class 3 was referred to as “rapidly decrease group.” And there were two stages in the development process of self-esteem in the adolescent group. The slope of the stable low level group showed a significant downward trend in the first stage and a significant upward trend in the second stage, with a relatively flat development trajectory and relatively low self-esteem on the whole. The slope of the rapidly rising group showed an insignificant upward trend in the first stage and a significant rapid upward trend in the second stage. The rapidly decrease group showed a significant and rapid downward trend in the first stage and a significant and rapid upward trend in the second stage. In the development of self-esteem in adolescence, there were three latent classes in which the characteristics of development trajectories were different. Age of 14 is the turning point between the two stages of development.

Theories of plasticity under complex loading along flat trajectories of deformations

The paper considers variants of theories of plastic flow with combined hardening, which are widely used in applied calculations of structures. A comparative analysis of the theories under complex loading along flat strain trajectories is carried out and covers the entire range of strain paths from multilink polylines to curved trajectories of constant and variable curvatures. The strain path from medium to large curvatures are considered. The analysis of the research results is carried out in the vector space of A.A. Il’yushin. We consider plane trajectories of deformations in the form of a square, three circles passing the origin of coordinates, and trajectories in an asteroid-like form. The results of the calculations are compared with the results of the experimental studies of the response stress trajectories, scalar and vector properties. Variants of theories are considered: isotropic hardening model; Ishlinsky-Prager-Kadashevich-Novozhilov model (linear kinematic and isotropic hardening); model similar to Ono-Wang's model; the Armstrong-Frederick-Kadashevich model (the Korotkikh model is based on this model); the Shabosh model with three evolutionary Armstrong-Frederick-Kadashevich equations; Themis model based on the invariant theory of plasticity; Bondar model with a three-term structure of the evolutionary equation for kinematic hardening. We give the material parameters (functions) that close the variants of plasticity theories. A satisfactory agreement with the experiment for all deformation trajectories is achieved in calculations based on the models of Ishlinsky-Prager-Kadashevich-Novozhilov, Shabosh and Temis. The difference between the results of calculations and experiments does not exceed 30 %. The best agreement with the experiment is achieved on the basis of the Bondar model with the difference between the results of the calculations and experiments for all trajectories less than 10 %.

Identification of Youthful Neurocognitive Trajectories in Adults Aging with HIV: A Latent Growth Mixture Model

Despite the neurocognitive risks of aging with HIV, initial cross-sectional data suggest a subpopulation of older people with HIV (PWH) possess youthful neurocognition (NC) characteristic of SuperAgers (SA). Here we characterize longitudinal NC trajectories of older PWH and their convergent validity with baseline SA status, per established SuperAging criteria in PWH, and baseline biopsychosocial factors. Growth mixture modeling (GMM) identified longitudinal NC classes in 184 older (age ≥ 50-years) PWH with 1–5 years of follow-up. Classes were defined using ‘peak-age’ global T-scores, which compare performance to a normative sample of 25-year-olds. 3-classes were identified: Class 1Stable Elite (n = 31 [16.8%], high baseline peak-age T-scores with flat trajectory); Class 2Quadratic Average (n = 100 [54.3%], intermediate baseline peak-age T-scores with u-shaped trajectory); Class 3Quadratic Low (n = 53 [28.8%], low baseline peak-age T-scores with u-shaped trajectory). Baseline predictors of Class 1Stable Elite included SA status, younger age, higher cognitive and physiologic reserve, and fewer subjective cognitive difficulties. This GMM analysis supports the construct validity of SuperAging in older PWH through identification of a subgroup with longitudinally-stable, youthful neurocognition and robust biopsychosocial health.

Water Infrastructure: Does the US Need a National Policy?

Although its investment needs lag the dominant transportation category, water infrastructure addresses human needs at a foundational level because it plays public health and economic roles. Much of it is old and not likely to be replaced soon, so federal policy must focus on intergovernmental leadership to sustain vital dams, urban water systems, and natural systems. Fixing the federal responsibility requires attention to intergovernmental relations and the conflicting goals of investment and regulation. Regulatory reform is ongoing, and normally not amenable to political initiatives. Federal water policies for both investment and regulatory controls seem to be on a flat trajectory, which is expected because they have evolved over decades. These can be summarized as: maintain federal dams and levees, invest in small grants and leveraging funds for state and local governments, address water justice issues, and operate essential programs like flood insurance. Public health and safety concerns will continue to dominate, more than in other infrastructure sectors. The future of water investments will be to hold the course with occasional shifts to respond to emergencies and new opportunities, such as greater private sector involvement.

Study of Kinematics and Dynamics of motion at Semanggi Bridge Jember, Indonesia as a contextual in Physics Learning

Some facts show that students often have difficulty in studying the kinematics and dynamics of motion. To overcome these problems, it takes learning experience that can help students build their knowledge about physics. One way is to connect the material physics with contextual phenomena because basically everything in nature can be learned based on physics studies. Semanggi Bridge located in Jember district is a connecting bridge that has a unique shape with three paths in the form of down, circle, and straight path. The studiesresults of kinematics and dynamics of motion on sloping and flat trajectories obtain physics quantities, ie position, distance, displacement, speed, velocity, kinematics and dynamics of motion on circular paths obtain physics quantities, ie angular position, angular velocity, angular acceleration, centripetal acceleration, centripetal force, and maximum speed. The studiesresults of kinematics and dynamics of motion can be used as a basis for designing contextual learning resources such as subject matter, sample questions, laboratory activities, and exercise questions related to contexts of physical phenomena.

Analysis of Droplet Characteristics and Kinetic Energy Distribution for Fixed Spray Plate Sprinkler at Low Working Pressure

HighlightsAn experiment was conducted to investigate the hydraulic performance of a fixed spray plate sprinkler (FSPS).A model was developed for estimating the cumulative kinetic energy of the FSPS under a moving system.The droplet characteristics and kinetic energy distribution were affected by the working pressure and FSPS structure.A high cumulative kinetic energy could lead to a low water infiltration rate into the soil.Abstract. The kinetic energy of droplets from a fixed spray plate sprinkler (FSPS) has a substantial influence on runoff and soil erosion, as well as on the energy consumption of moving sprinkler irrigation systems. To determine the droplet characteristics and kinetic energy of an FSPS, an experiment was conducted to investigate the effects of working pressure, plate structure, and nozzle size on the droplet diameter, velocity, and kinetic energy. Two plates (the FSPSB with a concave trajectory and deep grooves in the blue plate, and the FSPSY with a flat trajectory and shallow grooves in the yellow plate) were used in the tests. The cumulative kinetic energy and water depth were calculated for a single sprinkler moving in a straight line. The results show that the FSPSB, which had deeper grooves in the plate, produced a larger droplet diameter than the FSPSY, with shallow grooves in the plate. The droplet landing velocities presented a logarithmic relationship with the droplet diameter, and velocities increased with an increase in droplet diameter. The peak specific power (SP) value of the FSPSB was 1.14 to 16.76 times that of the FSPSY. When the working pressure was less than 150 kPa, the peak SP of the FSPSB remained at a high level. With an increase in working pressure, the peak SP of the FSPSB initially increased and then decreased, while the peak SP of the FSPSY increased. The cumulative kinetic energy of the FSPSB was higher than that of the FSPSY under mobile spray conditions. Compared with the cumulative water depth, the cumulative kinetic energy of the FSPSB increased and then decreased as the working pressure increased for the same applied water volume. Because the soil had a lower infiltration rate under the FSPSB, surface ponding was more likely to occur with the FSPSB than with the FSPSY at low working pressure. Keywords: Cumulative kinetic energy, Droplet size, Specific power, Sprinkler irrigation, Working condition.

Effects of Plate Structure and Nozzle Diameter on Hydraulic Performance of Fixed Spray Plate Sprinklers at Low Working Pressures

HighlightsThe hydraulic performance of fixed spray plate sprinklers (FSPS) was evaluated at low working pressures.The effects of geometric structure on the hydraulic performance of FSPS were studied.A model was developed for estimating the application depth and uniformity of FSPS under a linear-move system.The recommended values of the most effective sprinkler combination spacing for FSPS are given.Abstract. Reducing the working pressure of sprinklers can effectively reduce the energy consumption of sprinkler irrigation systems. Fixed spray plate sprinklers (FSPS) have a simple structure, and their working pressure has potential to be reduced to 40 kPa. To evaluate the hydraulic performance of FSPS at low pressure, an experiment was conducted to investigate the effects of working pressure, plate structure, and nozzle diameter on sprinkler flow rate, wetted radius, and water application distribution. Two plates (FSPSB and FSPSY) and five nozzles were used in the tests. The cumulative water application depth and irrigation uniformity coefficient were calculated under a linear-move system. The results show that sprinklers with larger nozzle diameters and higher working pressures produce greater coefficients of discharge. The wetted radius gradually increases with the increase in working pressure and nozzle diameter. Two empirical equations for estimating the wetted radius of the two plates are proposed. The FSPSB has a concave trajectory structure that produces a longer wetted radius than the FSPSY, which has a flat trajectory structure. Along the wetted radius, the water application rate increases and then decreases, with a peak value at a certain distance. For the FSPSB, the peak rate of water application decreases with increasing working pressure. However, the FSPSY shows the opposite trend, with the maximum peak value occurring at the highest working pressure of 250 kPa. The water distribution for a single FSPSB sprinkler is discrete due to the greater water dispersal caused by the deeper grooves in the plate. In contrast, a single FSPSY sprinkler provides a more uniform water distribution. The irrigation uniformity of the FSPSY is higher than that of the FSPSB. The recommended values for the most effective sprinkler combination spacings for FSPSB and FSPSY are given in this article. The results may be useful for selecting appropriate sprinklers in hydraulic design procedures. Keywords: Cumulative spray water depth, Irrigation uniformity, Sprinkler irrigation, Water distribution, Working condition.

Differentially flat trajectory generation and controller design for a quadrotor UAV

A control strategy of differentially flat trajectory generation and a backstepping controller for tracking the desired trajectory are developed for a quadrotor unmanned aerial vehicle (UAV). A glob...

Differentially flat trajectory generation and controller design for a quadrotor UAV

Differentially flat trajectory generation and controller design for a quadrotor UAV