Linear Moment Research Articles

ANALYSIS OF MICRO-STRIP PATCH ANTENNA FOR WI-FI APPLICATIONS

For the purposes of Wi-Fi applications, the objective of this Rectangular Micro-Strip Patch antenna design. The aim of this research paper is to design, simulate, test and analyses a new form of rectangular micro-stip patch antenna with both RT Duroid and two-feed line substrates. The proposed model consists of the Linear Polarization Moment Process. The latest concept analytical analysis is simulation using the HFSS tool and the ZNB20 vector network analyzer (VNA) is used for experimental validation.

Origin and Properties of Hydrothermal Tremor at Lone Star Geyser, Yellowstone National Park, USA

AbstractGeysers are rare geologic features that intermittently discharge liquid water and steam driven by heating and decompression boiling. The cause of variability in eruptive styles and the associated seismic signals are not well understood. Data collected from five broadband seismometers at Lone Star Geyser, Yellowstone National Park are used to determine the properties, location, and temporal patterns of hydrothermal tremor. The tremor is harmonic at some stages of the eruption cycle and is caused by near‐periodic repetition of discrete seismic events. Using the polarization of ground motion, we identify the location of tremor sources throughout several eruption cycles. During preplay episodes (smaller eruptions preceding the more vigorous major eruption), tremor occurs at depths of 7–10 m and is laterally offset from the geyser's cone by ~5 m. At the onset of the main eruption, tremor sources migrate laterally and become shallower. As the eruption progresses, tremor sources migrate along the same path but in the opposite direction, ending where preplay tremor originates. The upward and then downward migration of tremor sources during eruptions are consistent with warming of the conduit followed by evacuation of water during the main eruption. We identify systematic relations among the two types of preplays, discharge, and the main eruption. A point‐source moment tensor fit to low‐frequency waveforms of an individual tremor event using half‐space velocity models indicates average VS ≳ 0.8 km/s, source depths ~4–20 m, and moment tensors with primarily positive isotropic and compensated linear vector dipole moments.

Normal transformation for correlated random variables based on L-moments and its application in reliability engineering

In this paper, a new method for normal transformation is proposed to transform correlated non-normal random variables into independent standard normal ones based on their first four linear moments (L-moments), standard deviations and correlation matrix. The complete monotonic expressions of the equivalent correlation coefficient are proposed and the applicable range of the original correlation coefficient to ensure the transformation's executability is identified. Numerical studies demonstrate that the admissible range of the normal transformation for correlated random variables based on L-moments is larger in scope than that based on ordinary central moments (C-moments), and the proposed method is effective for normal transformations and sufficiently accurate for reliability engineering practices.

Merge L-Moment Method, Regional Frequency Analysis and SDI for Monitoring and Zoning Map of Short-Term and Long-Term Hydrologic Droughts in the Khuzestan Province of Iran

In recent years, the climatic change and global warming have affected on meteorological and hydrologic conditions in dry and warm regions. The severity of occurred droughts has increased in these regions. This research monitors 3- , 6- , 9- and 12-month hydrologic drought severity in the Khuzestan Province, with 51 hydrometric stations, based on drought return periods and streamflow drought index (SDI). The length of the statistical period is 62 years (1954–2016). Application of homogeneity statistic shows that the Khuzestan Province has 3 homogeneous regions for three-month time scale and 2 homogeneous regions for other time scales. The applied method for regional frequency analysis is linear moment method. By increasing of linear moment parameters, intensity of droughts will increase and drought return periods will reduce. Results of research show that severe and extreme hydrologic droughts can observe at the whole of this province in near future. Return period of these droughts is larger than 5 years. Also, intensity of hydrologic drought is milder in north and east of this province.

Experimental investigation of higher harmonic wave loads and moments on a vertical cylinder by a phase-manipulation method

This paper considers wave loads on bottom mounted vertical cylinders in the regime relevant to offshore wind turbine monopiles, examining the higher harmonics of the loading from non-breaking waves which are important in engineering design. Although we consider measurements of total force, our focus is on the moments applied about the seabed which have received much less attention in the literature. We consider an empirical ‘Stokes-like’ model whereby the magnitude of the higher harmonics of force or moment are dependent on the linear force or moment time-series raised to an appropriate power and a fixed coefficient. We compare this representation to high quality wave flume measurements and fully non-linear potential flow simulations. In general we find good agreement for all of the harmonic structure except for the triple frequency component where there are significant discrepancies. We also extend the Stokes-like model and show that harmonics of moments can be robustly predicted from the force harmonic and an appropriate constant moment arm for each harmonic, so a more elaborate calculation is generally not necessary.

In-plane non-linear elastic stability of arches subjected to multi-pattern distributed load

Abstract This paper proposes a numerical and an approximate analytical method for the in-plane non-linear elastic stability of arches under the multi-pattern distributed load. There are six key parts in this paper. Firstly, the approximate analytical solution for funicular axis of arches subjected to the multi-pattern distributed load is derived from the approximations of linear elastic bending moment and horizontal reaction force in the arch end. Secondly, the numerical solution of the in-plane non-linear elastic equilibrium equation is solved by using the shooting method and the bisection method simultaneously. Thirdly, the approximate analytical solutions for the in-plane non-linear elastic equilibrium are derived according to the approximate analytical solution for funicular arch axis obtained from the first part, the simplified strain-displacement expression in Cartesian coordinate system and the virtual work principle. Fourthly, a key parameter is proposed to transform the approximate analytical solutions into the corresponding equations of catenary and parabolic arches. Fifthly, the in-plane non-linear elastic symmetric and asymmetric buckling of arches under the multi-pattern distributed load is derived analytically. Lastly, the in-plane non-linear elastic buckling behaviors of arches subjected to multi-pattern distributed load are deduced based on the obtained analytical solutions. The multi-pattern distributed load with the uniformly distributed load along the span and the uniformly distributed load along the arch is selected as example to verify the proposed method. Comparisons with numerical solutions demonstrate that the proposed approximate analytical solutions for the funicular arch axis and linear elastic horizontal reaction force agree well with the results of Runge-Kutta method and the proposed approximate buckling predictions have sufficient accuracy compared with the results of finite element method in different rise-to-span ratios, relative slenderness and arch axis parameters.

O8.2. VALIDATION OF A COMPUTERIZED ADAPTIVE TESTING TOOL FOR PSYCHOSIS: THE CAT-PSYCHOSIS BATTERY

BackgroundTime constraints limit the use of measurement-based approaches in the routine clinical management of schizophrenia. Computerized Adaptive Testing (CAT) uses computational algorithms (item response theory - IRT) to match individual subjects with only the most relevant questions for them, reducing administration time and increasing measurement efficiency and scalability. This study aimed to test the psychometric properties of the newly developed CAT-Psychosis battery, both self-administered and rater-administered versions.MethodsPatients rated themselves with the self-administered CAT-Psychosis which yields a current psychotic severity score. The CAT-Psychosis is based on a multidimensional extension of traditional IRT-based CAT that is suitable for complex traits and disorders such as psychosis. Two different raters independently conducted the rater-administered CAT-Psychosis to test inter-rater reliability (IRR). The Brief Psychiatric Rating Scale (BPRS) was administered to test convergent validity. Subjects were re-tested within 7 days to assess test-retest reliability. Generalized linear mixed models and Pearson product moment correlation coefficients were used to test for correlations between individual ratings and average CAT-Psychosis severity scores respectively and the BPRS. Intraclass correlation coefficients (ICCs) were used to test for reliability. Generalized linear and non-linear (logistic) mixed models were used to estimate diagnostic discrimination capacity (lifetime ratings) and to estimate diagnostic sensitivity, specificity and area under the ROC curve with 10-fold cross validation.Results135 subjects with psychosis and 25 healthy controls were included in the study. Mean age of the sample was 33.1 years, standard deviation (SD)=12.2years; 62% were males. No significant differences were detected between groups (p=0.9064 and p=0.2684 respectively). Mean length of assessment was 7 minutes and 9 seconds (SD: 5:04min) for the clinician-administered version and 1 minute and 49 seconds (SD: 1:35min) for the self-administered version, averaging 11.4 and 12.6 questions each. Convergent validity against BPRS was moderate for both rater-administered (r=0.65 (0.55–0.73); Marginal Maximum Likelihood Estimation (MMLE)=0.052, Standard Error (SE)=0.005, p<0.00001) and self-administered (r=0.66; MMLE=0.057, SE=0.005, p<0.00001) versions. Clinician version’s IRR was strong (ICC=0.67 (Confidence Interval (CI): 0.51–0.80)), and test-retest reliability was strong for both self-report (ICC=0.83 (CI: 0.76–0.87) and clinician (ICC=0.87 (CI: 0.75–0.94) version. The CAT-Psychosis clinician version was able to discriminate psychosis vs. healthy controls (Area Under the ROC Curve (AUC)=0.96 (CI: 0.90–0.97)). CAT-Psychosis self-report yielded similar results (AUC= 0.85 (CI: 0.77–0.88)).DiscussionCAT-Psychosis provides valid severity ratings that mirror BPRS total scores, even as a self-report, yielding a dramatic reduction in administration time, while maintaining reliable psychometric properties. Furthermore, CAT-Psychosis, both clinician and self-report versions, is able to reliably discriminate psychotic patients based on a lifetime diagnosis from healthy controls after a brief assessment of current symptomatology.

Monotonic Expression of Polynomial Normal Transformation Based on the First Four L-Moments

Structural reliability analysis without the exclusion of random variables with unknown distributions has attracted increasing attention, and many endeavors have been devoted to this aspect. Recently, linear moments (L-moments) have been found increasing use for characterizing random variables with unknown distributions, in part since they show less sensitivity to distribution tails and are more stable than the ordinary central moments (C-moments). In this paper, the clear definition of the complete monotonic expressions of the third-order polynomial normal transformation (TPNT) under different combinations of the first four L-moments of random variables is first proposed. Additionally, the applicable boundaries and monotonic regions of TPNT based on L-moments are also determined. The advantages of the TPNT based on L-moments are that it has a wider applicable range and is much more stable under a small sample size compared with the TPNT based on C-moments, which are demonstrated through numerical example studies. Through the numerical examples, the proposed TPNT based on the first four L-moments is found to be quite effective for normal transformation.

GMM identification and estimation of peer effects in a system of simultaneous equations

This paper considers the identification and estimation of network models with agents interacting in multiple activities. We establish the model identification using both linear and quadratic moment conditions. The quadratic moment conditions exploit the correlation of individual decisions within and across different activities, and provide an additional channel to identify peer effects. Combining linear and quadratic moment conditions, we propose a general GMM framework for the estimation of simultaneous equations network models. The GMM estimator improves the asymptotic efficiency of the existing IV-based linear estimators in the literature. Simulation experiments show that the GMM estimator performs well in finite samples.

On Using Conventional and TL moments for the Estimation of a Mixture of Exponential Distributions, A Theoretical Review

This paper focuses on derivation of a mixture of exponential distribution and Linear Moments (LM) and Trimmed Linear moments (TL) is derived for estimation of its parameters. A comparison was made between L-moments, TL-moments of two component mixture of exponential distributions and conventional moments. In intensive simulation study, empirical study results are in the favor of conventional moments, the reason is that the L and TL-moments provided sometimes nearly unbiased results; sometimes much biased. Due to this vast variation, admittedly this study is in the favor of the conventional moments even its results are not much accurate and efficient.

Dynamic Spatial Panel Models: Networks, Common Shocks, and Sequential Exogeneity

This paper considers a class of generalized methods of moments (GMM) estimators for general dynamic panel models, allowing for weakly exogenous covariates and cross‐sectional dependence due to spatial lags, unspecified common shocks, and time‐varying interactive effects. We significantly expand the scope of the existing literature by allowing for endogenous time‐varying spatial weight matrices without imposing explicit structural assumptions on how the weights are formed. An important area of application is in social interaction and network models where our specification can accommodate data dependent network formation. We consider an exemplary social interaction model and show how identification of the interaction parameters is achieved through a combination of linear and quadratic moment conditions. For the general setup we develop an orthogonal forward differencing transformation to aid in the estimation of factor components while maintaining orthogonality of moment conditions. This is an important ingredient to a tractable asymptotic distribution of our estimators. In general, the asymptotic distribution of our estimators is found to be mixed normal due to random norming. However, the asymptotic distribution of our test statistics is still chi‐square.

FDI (Foreign Direct Investments) as Correlate of Rwanda Economic Development

This study examines the foreign direct investment as correlation to the economic development of Rwanda. The research was influenced by three investigation questions while using the time series approach. The secondary data used was collected from the stock exchange of Rwanda. The data was then analyzed using simple linear regression and Pearson products moment correlation with the application of SPSS, 23 (Statistical packages for social sciences). The findings showed that there’s a critical relationship between the exchange rate and direct foreign investment in Rwanda. The study concludes that direct foreign investment poses a considerable effect on the market share and importation of Rwanda. The study suggests that the government of Rwanda needs to develop a more friendly business environment and economic policies that will virtually attract FDI into every economic sector of the country.

Springback Analysis of AA5754 under Warm Stamping Conditions

Prediction of springback has been thoroughly investigated for cold forming processes; however with the rising prominence of lightweight materials and new forming technologies, predicting springback at elevated temperatures has become essential. In this paper, three analytical models and one empirical model were proposed to predict springback of an aluminium alloy AA5754 at warm forming conditions. The analytical models developed were based on the effect of the linear bending moment, uniform bending moment and through-thickness stress gradient respectively on springback, while the empirical model was developed using the results of L-shape bending tests. The model predictions were compared with the experiment results for various forming conditions. At room temperature, all four models had very good agreement. At elevated temperatures, the linear bending moment model was preferred for a die radius of 8mm, whereas empirical and stress gradient models were more suitable for a die radius of 4mm; in both cases, very close agreement was achieved where errors were within 5%.

Inelastic lateral buckling of steel cantilevers

Steel cantilevers are very different from the simply supported beams under uniform bending which provide the basis for designing steel members against lateral buckling. Cantilevers have different end restraint conditions, while the most critical loading condition for cantilevers is one of concentrated end load leading to a linear moment distribution. Thus the elastic lateral buckling formulations for uniform bending of simply supported beams used more generally for design are inappropriate for cantilevers.The mono-symmetric yield patterns in simply supported beams with residual stresses in uniform bending are of opposite sense to those of cantilevers because of the opposite sense of the bending moments. Thus formulations which take account of the effect of mono-symmetry on the inelastic lateral buckling of simply supported beams are inappropriate for cantilevers. Further, the linear cantilever moment distribution leads to very localised yielding instead of the uniform yielding of beams under uniform bending.This paper studies the inelastic lateral buckling of cantilevers in order to produce better design guidance than that currently based on the inelastic buckling of simply supported beams in uniform bending. The effects of mono-symmetry on the elastic buckling of beams and cantilevers are first investigated, and then the effects of the mono-symmetric non-uniform yielding patterns which complicate the prediction of the inelastic buckling resistances of cantilevers are studied. Cantilevers with reduced (instead of rigid) end warping restraints occur in overhanging beams, and so the effects of yielding on overhanging segments are also studied.These studies are used to develop simple approximate methods for designing cantilevers and overhanging segments against inelastic lateral buckling.

ANALYSIS OF PROFITABILITY OF ORANGE FLESH SWEET POTATO (Ipomea batata) IN OSUN STATE, NIGERIA

Nigeria is a major producer of sweet potato in Sub-Saharan Africa (SSA). This study looked at resource use efficiency and profitability of Orange Flesh Sweet Potato (OFSP) in Osun State, Nigeria. Two out of the three zones in Osun State were randomly selected from which six blocks were selected; and thirty cells were randomly selected from the six blocks. Two Hundred and Fifty (250) respondents were randomly selected across the thirty cells for the study. Data were analyzed using linear regression and Pearson Product Moment Correlation (PPMC). Results of the study showed that respondents are agile and active in orange flesh sweet potato production, with mean age of 38.8 years and had wealth of experience (12.6 years). Most (82.4%) of the respondents cultivated orange flesh sweet potato on ridges, 78.8% used hired labour and 92.4% used personal savings for orange flesh sweet potato farming. The average yield of orange flesh sweet potato was 6.20 tonnes/ha, the Total Revenue (TR) was ₦127,999.93/ha while the profit was ₦46,841.93/ha. Major limitations to orange flesh sweet potato production are inadequate finance (83.2%), poor extension service support (80.45), and inadequate market information (74%). Results of linear regression showed that land (t = 3.146, p = 0.001), labour (t = -3.105, p = 0.003), agrochemicals (t = 8.499, p = 0.000), and seeds (t = 3.928, p = 0.004) were determinants of orange flesh sweet potato production (p &lt; 0.05). In addition, correlation revealed negative relationship between constraints faced by the respondents and profit realized from orange flesh sweet potato production (r = -0.72, p = 0.01). The study concluded that orange flesh sweet potato production was profitable. It was recommended that soft credits should be extended to sweet potato farmers by the banks in the study area.&#x0D; &#x0D;

Theoretical background and application of MANSIM for ship maneuvering simulations

In this study, a new developed code, MANSIM (MANeuvering SIMulation) for ship maneuvering simulations and its theoretical background are introduced. To investigate the maneuverability of any low-speed ship with single-rudder/single-propeller (SPSR) or twin-rudder/twin-propeller (TPTR) configurations, a 3-DOF modular mathematical model or empirical approaches can be utilized in MANSIM. In addition to certain maneuvers of ships such as turning or zigzag, free maneuver can also be simulated. Input parameters required to solve the equations of motion can be estimated practically by several empirical formulas embedded in the software. Graphical user interface of the code has simple design to enable users to perform maneuvering calculations easily. In addition to results such as advance, transfer, tactical diameters etc. on the user interface, simulation results can also be analyzed graphically; thus it is possible to examine the variation of kinematic parameters during simulation. Using the code, maneuverabilities of a tanker ship (KVLCC2) and a surface combatant (DTMB5415) is investigated and computed results are compared with free running data for validation purpose. MANSIM can be advantageous for parametric studies and it is a valuable tool especially for sensitivity analysis on ship maneuvering. The software is available online at www.mansim.org. The effects of variation of hydrodynamic derivatives and rudder parameters on general maneuvering performance of ships are investigated by performing sensitivity analyses. It is found that linear moment derivatives and rudder parameters are highly effective in maneuvering motion. Another interesting outcome of this study is identification of the significance of third order coupled derivatives for DTMB5415 hull. Effects of linear derivatives on maneuvering indices are also investigated by MANSIM. Results show that there is not a linear relationship between hydrodynamic derivatives and maneuvering indices.

Pengaruh Hafalan Al-Quran Terhadap Prestasi Belajar Pada Mata Pelajaran Alquran Hadist Kelas XI MIA.1 MAN 2 Parepare

The research was conducted in framework to determine the influence of Al Quran memorized to student learning achievement of XI natural science class MAN 2 Parepare. Learning achievement is a student’s attainment result from the learning is got at school in period which have been settled at Al Quran hadist lesson. While Al Quran hadist is the lesson which is inside it learn about Al Quran verses and hadist texts in order to comprehend Al Quran and Hadist content. This research was taken place in MAN 2 Parepare began in April to june with research sample was all students of XI MIA 1 class counted 23 persons. Data was taken by inquiry got from students. Method which was used was linear regretion analysis caorrelation product moment significant level 5%. Research of processing data was showed r count equal to 0,6270 with degree of freedom = 23-2=21 significant level 5 % resulted table 0,3932 it means hypothesis nothing (Ho) is rejected and alternative hypothesis (Ha) is accepted means there is influence Al Quran memorized to student’s learning achievement.

Passive range of motion of the hips and shoulders and their relationship with ball spin rate in elite finger spin bowlers

ObjectivesInvestigate rotational passive range of motion of the hips and shoulders for elite finger spin bowlers and their relationship with spin rate. DesignCorrelational. MethodsSpin rates and twelve rotational range of motion measurements for the hips and shoulders were collected for sixteen elite male finger spin bowlers. Side to side differences in the rotational range of motion measurements were assessed using paired t-tests. Stepwise linear regression and Pearson product moment correlations were used to identify which range of motion measurements were linked to spin rate. ResultsSide to side differences were found with more external rotation (p = 0.039) and less internal rotation (p = 0.089) in the bowling shoulder, and more internal rotation in the front hip (p = 0.041). Total arc of rotation of the front hip was found to be the best predictor of spin rate (r = 0.552, p = 0.027), explaining 26% of the observed variance. Internal rotation of the rear hip (r = 0.466, p = 0.059) and the bowling shoulder (r = 0.476, p = 0.063) were also associated with spin rate. ConclusionsThe technique and performance of elite finger spin bowlers may be limited by the passive range of motion of their hips and shoulders. The observed side to side differences may indicate that due to the repetitive nature of finger spin bowling adaptive changes in the rotational range of motion of the hip and shoulder occur.

Effects of Leadership Style on Employee Performance of Fast Moving Consumer Goods (FMCGS) in South Africa

Abstract: The study seeks to assess the effects of leadership style on Employee performance (EP) of fast moving consumer goods (FMCGs) companies in South Africa. The specific objectives are: to determine the effects of autocratic leadership style on EP; to evaluate the effect of participative/ democratic leadership style on EP; to ascertain the relationship between laissez faire leadership style and EP; to assess the relationship between transactional leadership style and EP in the FMCGs. Quantitative research survey design was adopted for the study; both primary and secondary sources of data were utilized during the investigation. The sample size of 233 was obtained from the estimated population using Rao soft online calculator at 5% error tolerance and 95% level of confidence. Data was collected via questionnaires and analyzed utilizing Simple Linear Regression (SLR) and Pearson product moment correlation (PPMC). It was discovered that there is a significant relationship between the various leadership styles and the performance of organisations. However, transactional leadership style was found to account for more influence on employee performance than other styles of leadership. Therefore, the study recommends the transactional style of leadership for managers of FMCGs in order to increase employee performance, ensure profitability and sustainability of the organisation.

The dynamical motion of a gyroscope subjected to applied moments

In the present work, the problem of the dynamical motion of a rigid body close to Lagrange’s gyroscope under the effectiveness of a gyro moment vector, perturbing moments, and a Newtonian field is examined. An averaging system of the governing equations of motion is gained in view of applying the averaging method. A case of linear dissipative moments is considered. The numerical solutions for the case of linear dissipative moments are achieved and represented in some plots to detect the well effect of the different parameters on the motion of the body. The prominence of this work is due to its great applications in physics and engineering industry.