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We investigated the convergent validity and intrasession reliability of force, velocity, and power (FVP) variables and the dynamic strength index (DSI) obtained from isometric midthigh pull (IMTP) and squat jump (SJ) testing. Fifteen male combat sports athletes (27 ± 5 years, 77 ± 9 kg, 1.76 ± 0.1 m, 14 ± 6% body fat) participated in a 2-days study. The first day involved testing familiarization, while the second was dedicated to IMTP and SJ testing. Maximal isometric force (Fiso) was obtained from IMTP, while mean force, mean velocity, jump height, and jump impulse (J) were gathered from SJ. To analyze the FVP, we calculated the linear relationship between force and velocity, which allowed us to obtain the slope of the relationship (SFV), the theoretical velocity at zero force (V0), and the theoretical maximal power (Pmax). DSI was obtained as a ratio from SJ peak force and Fiso. The convergent validity was investigated using Spearman’s ρ coefficients to assess the relationships between jump height and J with Fiso, V0, SFV, Pmax, and DSI. The intrasession reliability was assessed using intraclass correlation coefficients (ICC) and coefficient of variations (CV). All variables demonstrated acceptable reliability scores. ICC ranged from moderate to excellent, and the mean CV was

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell 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.)

Every company has an obligation to provide wages to employees in accordance with the provisions. The provision of wages according to the standard aims to ensure that workers earn an income that can meet the needs of a decent life. The compensation system is considered important in an organization because it has a direct impact on employee motivation and performance. This study aims to assess the compensation system in UKM XYZ in Cilegon City, which is engaged in the culinary sector, and provide recommendations for improving the compensation system. The methods used in this study are determining job value based on compensation factors using the Hay method, determining job grading using the given grade and minimum maximum methods, and salary mapping using the two-point method. The results obtained from this study indicate that the compensation system in the form of salary at UKM XYZ is still not ideal because it is below the minimum wage and there is no job grading determination yet. There are ten compensable factors needed in determining the compensation system for UKM XYZ. Improvements were made by calculating job values and dividing job titles into four grades. Based on salary mapping for a more ideal compensation system, the results show that salary mapping using the two-point method can be considered by SMEs for future implementation because it already meets the minimum wage and is adjusted to the budget of UKM XYZ. [ABSTRACT FROM AUTHOR]

Copyright of Revija Šport is the property of Sport: Revija Za Teoreticna in Praticna Vprasanja Sporta 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 China Mechanical Engineering is the property of Editorial Board of China Mechanical 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.)

This study aimed to compare and associate the magnitude of the load–velocity relationship variables between the multiple-point and two-point methods and between the concentric-only and eccentric–concentric prone bench pull (PBP) variants. Twenty-three resistance-trained males completed a preliminary session to determine the concentric-only PBP one-repetition maximum (1 RM) and two experimental sessions that only differed in the PBP variant evaluated. In each experimental session they performed three repetitions against the 14 kg load (L1), two repetitions against the 85% 1 RM load (L4), three repetitions against an equidistant intermediate light load (L2), two repetitions against an equidistant intermediate heavy load (L3), and 1–5 1 RM attempts. The load–velocity relationship variables (i.e., load–axis intercept, velocity–axis intercept, and area under the load–velocity relationship line) were obtained from the multiple-point (L1-L2-L3-L4) and two-point (L1-L4) methods. All load–velocity relationship variables presented greater magnitudes when obtained by the two-point method compared with the multiple-point method (p < 0.001, ESrange = 0.17–0.43), while the load–velocity relationship variables were comparable between both PBP variants (p ≥ 0.148). In addition, the load–velocity relationship variables were highly correlated between both methods (rrange = 0.972–0.995) and PBP variants (rrange = 0.798–0.909). When assessing the load–velocity relationship variables, practitioners should prescribe only two loads, as this maximises the magnitudes of the variables and decreases fatigue. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the effectiveness of two resistance training (RT) programmes (free weight [FW] and elastic band [EB]) on velocity variables (handball throwing velocity [HTV] and maximal theoretical velocity [V0]) using load-velocity (L-V) relationship modelling. Both programmes lasted 6 weeks and consisted of performing bench press and overarm dumbbell pull-over using free weights (FW group) or elastic bands (EB group). Nineteen male sports science students were randomly assigned to EB (n=10) or FW group (n=9). Both RT programmes increased HTV and V0, although the increment was greater in the FW (>2 m·s-1) compared to the EB group (<1 m·s-1). RT programmes had selective effects on the strength variables being FW more effective in increasing 1-repetition maximum, while EB in increasing maximal isometric force. Very large correlations were observed between two-point (L-V relationship modelled through two pairs of L and V data) and multiple-point methods (L-V relationship modelled through six pairs of L and V data) (V0: r=0.96; HTV: r=0.93). All coefficients of variation showed high validity both for V0 and HTV (=6.2%). Altogether, FW training should be used for increasing the velocity of the throwing performance, while the two-point method for following training-induced changes. [ABSTRACT FROM AUTHOR]

Purpose: To explore the feasibility of the linear force-velocity (F-V) modeling approach to detect selective changes of F-V parameters (ie, maximum force [F0], maximum velocity [V0], F-V slope [a], and maximum power [P0]) after a sprint-training program. Methods: Twenty-seven men were randomly assigned to a heavy-load group (HLG), light-load group (LLG), or control group (CG). The training sessions (6 wk x 2 sessions/wk) comprised performing 8 maximal-effort sprints against either heavy (HLG) or light (LLG) resistances in leg cycle-ergometer exercise. Pre- and posttest consisted of the same task performed against 4 different resistances that enabled the determination of the F-V parameters through the application of the multiple-point method (4 resistances used for the F-V modeling) and the recently proposed 2-point method (only the 2 most distinctive resistances used). Results: Both the multiple-point and the 2-point methods revealed high reliability (all coefficients of variation <5% and intraclass correlation coefficients >.80) while also being able to detect the group-specific training-related changes. Large increments of F0, a, and P0 were observed in HLG compared with LLG and CG (effect size [ES] = 1.29-2.02). Moderate increments of V0 were observed in LLG compared with HLG and CG (ES = 0.87-1.15). Conclusions: Short-term sprint training on a leg cycle ergometer induces specific changes in F-V parameters that can be accurately monitored by applying just 2 distinctive resistances during routine testing. [ABSTRACT FROM AUTHOR]

This study determined the optimal resistive forces for testing muscle capacities through the standard cycle ergometer test (1 resistive force applied) and a recently developed 2-point method (2 resistive forces used for force-velocity modelling). Twenty-six men were tested twice on maximal sprints performed on a leg cycle ergometer against 5 flywheel resistive forces (R1-R5). The reliability of the cadence and maximum power measured against the 5 individual resistive forces, as well as the reliability of the force-velocity relationship parameters obtained from the selected 2-point methods (R1-R2, R1-R3, R1-R4, and R1-R5), were compared. The reliability of outcomes obtained from individual resistive forces was high except for R5. As a consequence, the combination of R1 (≈175 rpm) and R4 (≈110 rpm) provided the most reliable 2-point method (CV: 1.46%-4.04%; ICC: 0.89-0.96). Although the reliability of power capacity was similar for the R1-R4 2-point method (CV: 3.18%; ICC: 0.96) and the standard test (CV: 3.31%; ICC: 0.95), the 2-point method should be recommended because it also reveals maximum force and velocity capacities. Finally, we conclude that the 2-point method in cycling should be based on 2 distant resistive forces, but avoiding cadences below 110 rpm. [ABSTRACT FROM AUTHOR]

We investigated the convergent validity and intrasession reliability of force, velocity, and power (FVP) variables and the dynamic strength index (DSI) obtained from isometric midthigh pull (IMTP) and squat jump (SJ) testing. Fifteen male combat sports athletes (27 ± 5 years, 77 ± 9 kg, 1.76 ± 0.1 m, 14 ± 6% body fat) participated in a 2-days study. The first day involved testing familiarization, while the second was dedicated to IMTP and SJ testing. Maximal isometric force ( F iso ) was obtained from IMTP, while mean force, mean velocity, jump height, and jump impulse ( J ) were gathered from SJ. To analyze the FVP, we calculated the linear relationship between force and velocity, which allowed us to obtain the slope of the relationship ( S FV ), the theoretical velocity at zero force ( V 0 ), and the theoretical maximal power ( P max ). DSI was obtained as a ratio from SJ peak force and F iso . The convergent validity was investigated using Spearman's ρ coefficients to assess the relationships between jump height and J with F iso , V 0 , S FV , P max , and DSI. The intrasession reliability was assessed using intraclass correlation coefficients (ICC) and coefficient of variations (CV). All variables demonstrated acceptable reliability scores. ICC ranged from moderate to excellent, and the mean CV was <10%. We found a "very large" correlation between jump J and P max , while jump height was not correlated with any variable. In conclusion, the IMTP and SJ combination is a practical way to determine FVP producing capacities that can be reliably measured (intrasession). The P max , derived from FVP, was correlated with jump performance, which might evidence the convergent validity of the method., Competing Interests: The authors declare that they have no competing interests., (© 2024 Vieira et al.)

An a-posteriori multicentre reliability study was conducted to compare the between-session reliability of the force-velocity relationship parameters (force-intercept [F0 ], velocity-intercept [v0 ], and maximum power [Pmax]) between different regression models during the bench press (BP) and bench press throw (BPT) exercises. Data from four and three studies were considered for the BP (n = 102) and BPT (n = 81) exercises, respectively. The force-velocity relationships were determined using five regression models: linear multiple-point, linear two-point, quadratic polynomial, hyperbolic, and exponential. All regression models provided F0 and Pmax with acceptable reliability (cut-off CV ≤ 9.45%; cut-off ICC ≥ 0.79) with the exceptions of F0 for the quadratic polynomial and hyperbolic models (BPT) and Pmax for the exponential model (BP and BPT). Only the linear multiple- and linear two-point models provided v0 with acceptable absolute reliability (cut-off CV ≤ 7.72%). Regardless of the exercise, the reliability of the three parameters was generally higher for the linear multiple- and two-point models compared to the other models (CVratio ≥ 1.22), and no significant differences were observed between multiple- and linear two-point models (CVratio ≤ 1.11). Linear regression models are recommended to maximise the reliability of the force-velocity relationship parameters during the BP and BPT exercises. [ABSTRACT FROM AUTHOR]

This study aimed at examining the concurrent validity and reliability of the multi-point method and the two-point method's variations for estimating the one-repetition maximum (1RM) in the deadlift and squat exercises and to determine the accuracy of which optimal two loads can be used for the two-point method protocol. Thirteen resistance-trained men performed six sessions that consisted of two incremental loading tests (multi-point method: 20-40-60-80-90% and two-point method variations: 40-60%, 40-80%, 40-90%,60-80%, 60-90%) followed by 1RM tests. Both the multi-point method and the two-point method load variations showed reliable results for 1RM estimation (CV < 10%) squat and deadlift exercises. Session-session reliability was found to be low in deadlift (ICC: 0.171-0.335) and squat exercises (ICC: 0.235-0.479) of 40-60% and 60-80% in two-point methods. Deadlift (ICC: 0.815-0.996) and squat (ICC: 0.817-0.988) had high session-to-session reliability in all other methods. Regarding the validity of deadlift exercise, the multipoint method (R2 = 0.864) and two variations of the two-point method (R2 = 0.816 for 40-80%, R2 = 0.732 for 60-80%) showed very large correlations, whereas other two variations of the two-point method (R2 = 0.945 for 40-90%, R2 = 0.914 for 60-90%) showed almost perfect correlations with the actual 1RM. Regarding the validity of squat exercise, the multi-point method (R2 = 0.773) and two variations of the two-point method (R2 = 0.0847 for 60-80%, R2 = 0.705 for 40-90%) showed very large correlations, whereas 40-60% variation showed almost perfect correlation (R2 = 0.962) with the actual 1RM. In conclusion, whereas both the multi-point method and the two-point method load variations showed reliable results, the multiple-point method and most of the two-point methods' load variations examined in this research provided an accurate (from large-moderate to perfect) estimate of the 1RM. Therefore, we recommend using the multi-point method and especially the two-point methods variations including higher relative loads to estimate 1RM. [ABSTRACT FROM AUTHOR]

This study aimed at examining the concurrent validity and reliability of the multi-point method and the two-point method’s variations for estimating the one-repetition maximum (1RM) in the deadlift and squat exercises and to determine the accuracy of which optimal two loads can be used for the two-point method protocol. Thirteen resistance-trained men performed six sessions that consisted of two incremental loading tests (multi-point method: 20–40–60–80–90% and two-point method variations: 40–60%, 40–80%, 40–90%,60–80%, 60–90%) followed by 1RM tests. Both the multi-point method and the two-point method load variations showed reliable results for 1RM estimation (CV < 10%) squat and deadlift exercises. Session-session reliability was found to be low in deadlift (ICC: 0.171–0.335) and squat exercises (ICC: 0.235–0.479) of 40–60% and 60–80% in two-point methods. Deadlift (ICC: 0.815–0.996) and squat (ICC: 0.817–0.988) had high session-to-session reliability in all other methods. Regarding the validity of deadlift exercise, the multipoint method (R2 = 0.864) and two variations of the two-point method (R2 = 0.816 for 40–80%, R2 = 0.732 for 60–80%) showed very large correlations, whereas other two variations of the two-point method (R2 = 0.945 for 40–90%, R2 = 0.914 for 60–90%) showed almost perfect correlations with the actual 1RM. Regarding the validity of squat exercise, the multi-point method (R2 = 0.773) and two variations of the two-point method (R2 = 0.0847 for 60–80%, R2 = 0.705 for 40–90%) showed very large correlations, whereas 40–60% variation showed almost perfect correlation (R2 = 0.962) with the actual 1RM. In conclusion, whereas both the multi-point method and the two-point method load variations showed reliable results, the multiple-point method and most of the two-point methods’ load variations examined in this research provided an accurate (from large-moderate to perfect) estimate of the 1RM. Therefore, we recommend using the multi-point method and especially the two-point methods variations including higher relative loads to estimate 1RM.

This study aimed to compare and associate the magnitude of the load–velocity relationship variables between the multiple-point and two-point methods and between the concentric-only and eccentric–concentric prone bench pull (PBP) variants. Twenty-three resistance-trained males completed a preliminary session to determine the concentric-only PBP one-repetition maximum (1 RM) and two experimental sessions that only differed in the PBP variant evaluated. In each experimental session they performed three repetitions against the 14 kg load (L1), two repetitions against the 85% 1 RM load (L4), three repetitions against an equidistant intermediate light load (L2), two repetitions against an equidistant intermediate heavy load (L3), and 1–5 1 RM attempts. The load–velocity relationship variables (i.e., load–axis intercept, velocity–axis intercept, and area under the load–velocity relationship line) were obtained from the multiple-point (L1-L2-L3-L4) and two-point (L1-L4) methods. All load–velocity relationship variables presented greater magnitudes when obtained by the two-point method compared with the multiple-point method (p < 0.001, ESrange = 0.17–0.43), while the load–velocity relationship variables were comparable between both PBP variants (p ≥ 0.148). In addition, the load–velocity relationship variables were highly correlated between both methods (rrange = 0.972–0.995) and PBP variants (rrange = 0.798–0.909). When assessing the load–velocity relationship variables, practitioners should prescribe only two loads, as this maximises the magnitudes of the variables and decreases fatigue.

An a-posteriori multicentre reliability study was conducted to compare the reliability and magnitude of the maximum power (Pmax) and optimal velocity (Vopt) between the force-power-velocity relationships during the leg cycle-ergometer and bench press throw exercises. The force-power-velocity relationships were determined in two separate sessions considering the values of force, velocity, and power collected under multiple loads. The force–velocity relationship was also determined from the force and velocity values collected under only the two most distant loads. Reliability of all regression models was high for Pmax and Vopt during the leg cycle-ergometer (CVrange: 1.73–2.98%) and for Pmax during the bench press throw (CVrange: 4.47–4.73%), while the reliability was acceptable for Vopt during the bench press throw (CVrange: 6.52–7.34%). Significant differences between the force-power-velocity relationships were observed for both Pmax and Vopt (P <.001). All regression models can be confidently used to determine Pmax and Vopt, but these should not be used interchangeably. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to explore the strength capacities of the injured and non-injured leg following a unilateral anterior cruciate ligament reconstruction. Methods: Eight elite soccer players (age = 25.5 ± 3.9 years; height = 1.83 ± 0.04 m; body mass = 78.9 ± 4.5 kg) volunteered to participate in this study. Nine months after the anterior cruciate ligament reconstruction and just before initiating the full training process, the maximal peak torque of the quadriceps and hamstring muscles were measured at 60 and 180 degrees/second using isokinetic dynamometry. Obtained peak torques were used for calculating hamstring-to-quadriceps ratio, limb symmetry index, and to estimate maximal torque capacity using a two-velocity method (i.e., linear torque-velocity relationship modeled considering peak torque obtained at 60 and 180 degrees/second). Results: No differences were found between hamstring-to-quadriceps ratios of the injured and non-injured leg (p = 0.165), nor between limb symmetry index of the quadriceps and hamstring muscles (p = 0.985), regardless of the angular velocity applied during tests. The two-point method revealed significant differences between quadriceps and hamstring muscle groups both in the injured and non-injured leg (p < 0.001; maximal estimated torque was higher for quadriceps compared to hamstring muscles), while the differences between same muscle groups of the different legs were not significant. Conclusions: Collectively, these findings indicate that 9 months were enough for reaching a certain strength level of the injured leg that permits a safe return to play. [ABSTRACT FROM AUTHOR]

This study aimed to compare the reliability and magnitude of the force-velocity (F-V) relationship parameters between the squat jumps performed from the 90° (SJ90) and self-preferred knee angle (SJpref). A secondary aim was to explore the effect of the analysis procedure (force platform [FP] and Samozino's [SAM] method) and the number of loads tested (three- and two-point methods) on the F-V relationships. Twelve men were tested in two sessions during the SJ90 and SJpref. Two identical blocks of jumps were performed in each session against three external loads. The F-V relationship parameters (maximum force, maximum velocity, F-V slope and maximum power) were determined at each block through the FP and SAM procedures using the data collected under three (three-point method) or only the two most distant loads (two-point method). The average coefficient of variation (CV) of the four F-V parameters revealed a higher reliability for the SJ90 compared to the SJpref (5.86% vs. 7.55%; CVratio = 1.29) with more pronounced differences using the FP (CVratio = 1.43) than the SAM procedure (CVratio = 1.14), and higher reliability for the SAM compared to the FP (6.14% vs. 7.27%; CVratio = 1.18). The SJpref and SAM procedures provided comparable or higher magnitude of the F-V relationship parameters than the SJ90 and FP, respectively. The three- and two-point methods revealed a comparable reliability and trivial differences in the magnitude of the F-V relationship parameters. The routine testing procedure of the F-V relationship could be simplified using the SJpref, the SAM procedure and the two-point method. [ABSTRACT FROM AUTHOR]

This review aims to provide an overview of the current load-velocity (L-V) approaches and their ability to estimate one-repetition maximum (1RM). The bench press exercise appears to be the most valid and reliable when applying this approach. The ability for L-V relationship to predict 1RM for lower-body lifts remains questionable. Individualized regression equations should be used alongside mean velocity when utilizing this method during the bench press. The 2-point method (2 distinguishable loads, as opposed to multiple loads) and normative velocity data (minimal velocity thresholds at 1RM) may provide a novel and practical way to assess athletes' 1RM. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department 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.)

In the discharge measurement work of lateral canals and field ditches, the accuracy of the traditional one- and two-point methods can barely satisfy the actual needs of the irrigation area. In this paper, a new type of channel flow measuring device and its accuracy improvement method are presented. The calibration and verification of the flow measurement system are carried out by laboratory tests. Results show that the mean absolute percentage errors (MAPEs) of the traditional one- and twopoint methods are 24.99% and 13.44%, respectively, whereas the MAPE of the proposed measurement system is only 3.04%. The proposed measurement method has higher measurement accuracy than the traditional methods and is a new and effective tool for channel flow measurement. [ABSTRACT FROM AUTHOR]

Soil water retention curve is an indicator of one of the most important soil hydrological properties that have high applications in various soil water issues, and it is widely estimated by the van Genuchten,s model. This research was performed to estimate the soil water characteristic curve by method of van Genuchten,s model. Thus for determination of Inverse solution, Two points model H5 of Rosetta program and two point-Rosetta methods were used. Using these coefficients, the performance and accuracy of these models in retention curve estimation were evaluated by correlation coefficient (R2), magnitude of absolute error (MAE), root mean square error (RMSE), Akaike information coefficient (AIC) and model efficiency (EF). The overall results showed that the statistical parameters of R2, EF, MAE (cm3/cm3), RMSE (cm3/cm3) and AIC for inverse solution were 0.997, 0.981, 0.013, 0.020, and -7344, respectively for Two point-Rosetta model were equal 0.983, 0.898, 0.026, 0.047 and -5754, for Two-point model were equal 0.98, 0.879, 0.027, 0.051 and -5595, respectively and for Rosetta were equal 0.978, 0.859, 0.039, 0.055 and -5440, respectively. According to these results, inverse method, two point-Rosetta and two-point had the highest accuracy in retention curve estimation, respectively. The Rosetta program had the lowest accuracy in this case. Comparison of methods for different textures showed that the inverse solution had the lowest error in all textures. Rosetta program, Two point-Rosetta and Two-point are recommended for coarse, Medium and fine textures, respectively.

This study was attempted to evaluate infiltration methods based on irrigation advance for furrow irrigation. Irrigation advance data were collected at Latif farm, Sindh Agriculture University, Tandojam for three irrigation events. To achieve the objectives of the study two different methods viz. Upadhyaya and Raghuwanshi and Valiantzas one-point, were tested against the two-point method. Evaluation of employed methods was undertaken to know the best method for the prediction of cumulative infiltration and advance. The results revealed that Upadhyaya and Raghuwanshi (ME=-5.25) and Valiantzas onepoint (ME=-0.99) are unsuitable for silt loam soil with their original constants as these methods show great scatter when compared with reference method and measured data. Thus, it is suggested that these methods must be evaluated before use. [ABSTRACT FROM AUTHOR]

In this paper we define a new two-point Newton-type method for finding a simple root of nonlinear equations. It is proved that the new method has the convergence order of nine requiring only four function evaluations per full iteration. The Kung and Traub conjecture states that multipoint iteration methods, without memory based on n function evaluations, could achieve maximum convergence order 2n-1. The new method produces however a convergence order of nine, which is better than the expected maximum convergence order of eight. Therefore, we show that this conjecture can fail for a particular set of nonlinear equations. The drawback of this new method is its restricted utilization to a zero simple root. It is demonstrated though that this method is very competitive with eighth-order methods. [ABSTRACT FROM AUTHOR]

The stability of a liquid jet subject to a transverse electric field is investigated in the framework of electrohydrostatic theory. It is shown that depending on the magnitude of permittivity ratio of the involved fluids S = ε i / ε o (inner to outer) compared to a critical permittivity ratio S cr ≈ 27.45 the jet exhibits distinct behaviors; for S < S cr the jet is stable and elongates indefinitely as the electric field is increased, while for S > S cr it shows hysteresis behavior and becomes unstable beyond a critical electric capillary number Ca cr . The results suggest that the jets are generally more stable than liquid drops. [ABSTRACT FROM AUTHOR]

Field data sets for seven irrigation events during maize growing season were collected for characterizing infiltration properties in variable Alternate, Fixed Alternate and Conventional Furrow Irrigation (AFI, FFI and CFI, respectively). Three various estimation methods; the two-point method and the INFILT and IPARM models; were used to estimate the infiltration parameters of the modified Kostiakov equation for alternate and conventional furrows and then compared with field results. Less runoff losses and larger infiltration were observed in alternate furrows as compared to conventional furrows due to increased lateral water movement to non-irrigated furrow. AFI had somewhat greater infiltration rate than FFI. The steady infiltration rate in AFI and FFI was higher than in CFI. The IPARM model had the most accurate and reliable performance relative to others in three irrigation treatments. However the two-point method also performed well. The INFILT model was not suitable on the experimental field studied and highly overestimated the infiltration for all irrigation treatments. The results indicated that measuring both advance and runoff data is necessary to achieve reasonable and precise infiltration parameters. Having different infiltration characteristics in alternate furrows, design variables of alternate furrow irrigation will be different from conventional furrow irrigation in the same field. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes a novel method to measure straightness error of an axis of motion with a system utilising taut wire, optical sensor and reference error cancellation technique. In contrast to commonly used taut wire, straightedge or laser-based methods it combines simplicity of setup and low cost with high levels of automation, accuracy and repeatability. An error cancellation technique based on two-point method is applied for the first time to a versatile reference object which can be mounted at any place of machine's working volume allowing direct measurement of motion straightness of a tool point. Experimental results on a typical machine tool validate performance of the proposed taut wire system with a commercial laser interferometer operating in the same conditions is used as a reference. The proposed method shows highly repeatable results of better than ±0.25μm over the range of 0.48m and measurement accuracy comparable to the interferometer of ±0.5μm. [Copyright &y& Elsevier]

Abstract: Non-linear algebraic equations must be solved by an iterative method, the non-linear equations being linearized by evaluating the non-linear terms with the known solution from the preceding iteration. The Newton–Raphson method, which is based on the Taylor series expansion and uses the tangent stiffness matrix, has been extensively used to solve non-linear problems. In this paper, a new Newton–Raphson algorithm is developed for analyses involving non-linear behavior. Our method, here named as a two-point method, is constructed as a predictor–corrector one, most frequently taking Newton''s method in the first iteration. It should be noted that our concern in this research ignores the problem of passing limit points. The presented method incorporates the known information at each stage of the loading process to determine the subsequent unknown variables. Compared with the classic Newton–Raphson algorithm, it offers a strategy that can be deployed to reduce both the number of the iterations and the computing time involved in non-linear analysis of structures. [Copyright &y& Elsevier]

Abstract: For straightness profile measurements, the traditional standard for hardware datums has been the straightedge, level and optical beam. Currently, the proliferation of computers has brought about development of the software datum. Conventional software datums are error separation techniques that separate a surface profile from parasitic motions by using multiple sensors and/or multiple arrangements (multiple orientations or multiple alignments). The multiple sensor method can separate the surface profile with just one scanning. Therefore, the multiple sensor method is useful, even if the parasitic motion includes non-repeatable components. However, random error propagation of the multiple sensor method has been reported in the case of large sampling numbers. In this paper, a novel two-point method for straightness profile measurement is proposed. The proposed method can reduce the propagation of uncertainty caused by the cross-axis motion, pitch motion and random error of the estimated surface profile. The proposed method consists of a weighted addition and inverse filtering. The suitable weight of the weighted addition that gives the least uncertainty propagation is derived by a simple equation using the standard deviation of the cross-axis motion, pitch motion and random error. [Copyright &y& Elsevier]

Abstract: In the straightness profile measurement of a mechanical workpiece, hardware datums have been the traditional standard. However, error separation techniques of the surface profile from parasitic motions have been developed. These are known as software datums, which separate the surface profile from the parasitic motions using multiple sensors and/or multiple orientations and realize higher accuracy than that of the hardware datum. However, the conventional software datum cannot measure a large-scale workpiece because the large sampling number causes random error amplification. Furthermore, the conventional software datum assumes that sensor''s random noise is small enough in comparison with the parasitic motions. But, the accuracy of the hardware datum has become high. Then, the accuracy of the sensor''s random noise is not so small, relatively. In this paper, a next-generation software datum, the two-point method based on the least uncertainty propagation, is proposed. The proposed two-point method consists of weighting and inverse filtering, resulting in the least uncertainty of the estimated surface profile by choosing suitable weighting. [Copyright &y& Elsevier]

We introduce a two-point Newton-like iteration with a geometrical interpretation similar to the Secant method which is essentially of quadratic order. A local as well as a semilocal convergence analysis is provided for this method on the basis of the majorant principle. The superiority of this method over others using the same type of hypotheses is established. Some numerical examples show how to choose in practice the operators involved. Finally, the monotone convergence of the method is examined on partially ordered topological spaces. [ABSTRACT FROM AUTHOR]

This article is concerned with the calculation of confidence intervals for simulation output that is dependent on two sources of variability. One, referred to as simulation variability, arises from the use of random numbers in the simulation itself; and the other, referred to as parameter variability, arises when the input parameters are unknown and have to be estimated from observed data. Three approaches to the calculation of confidence intervals are presented-the traditional asymptotic normality theory approach, a bootstrap approach and a new method which produces a conservative approximation based on performing just two simulation runs at carefully selected parameter settings. It is demonstrated that the traditional and bootstrap approaches provide similar degrees of accuracy and that whilst the new method may sometimes be very conservative, it can be calculated in a small fraction of the computational time of the exact methods. [ABSTRACT FROM AUTHOR]

The aim of this study was to quantify the relative concentrations of oxyhemoglobin and deoxyhemoglobin within the light path of the brain and to estimate cerebral hemoglobin (Hb) oxygen saturation using full-spectrum near-infrared spectroscopy (fsNIRS). For this purpose, we developed a novel exponential correction equation as well as a two-point spectroscopy method to estimate the relative concentrations of Hb and Hb oxygen saturation in biological tissues. The results of evaluation of measurements using an in vitro model indicated that our fsNIRS method enables accurate and non-invasive measurements of Hb content and saturation in a highly scattered medium such as the human brain. According to the results of analysis using a hypoxic piglet model, the mean cerebral Hb oxygen saturation (SbO2) of newborn piglets at an inspired oxygen gas concentration of 0.21 was estimated to be 63±4% (mean±S.D.). Umbilical arterial and left internal jugular venous Hb oxygen saturation were simultaneously estimated to be 96±2% and 52±11%, respectively. SbO2 and arterial Hb oxygen saturation values had a linear relationship. The average oxygenation state of cerebral tissue is comparable with that of the cerebral vein. The results of this study showed that our method can be used to monitor Hb oxygen saturation in the neonatal brain at the bedside in an intensive care unit. [Copyright &y& Elsevier]