Intermediate-Variable-Based Distributed Fusion Estimation for Wind Turbine Systems

In wind turbine systems, the state of the generator is always disturbed by various unknown perturbances, which leads to system instability and inaccurate state estimation. In this paper, an intermediate-variable-based distributed fusion estimation method is proposed for the state estimation problem in wind turbine systems. By constructing an augmented state error system and using the idea of bounded recursive optimization, the local estimators and distributed fusion criterion are designed, which can be used to estimate the disturbance signals and system states. Then, the local estimator gains and the distributed weighting fusion matrices are obtained by solving the established convex optimization problems. Furthermore, a compensation strategy is designed by using the estimated disturbance signals, which can potentially reduce the influence of the disturbance signals on the system state. Finally, a numerical simulation is provided to show that the proposed method can effectively improve the accuracy of the estimation of the wind turbine state and disturbance, and the superiority of the proposed method is illustrated as a comparison to the Kalman fusion method.

Victimization

Not all groups are equally likely to be subject to acts of aggression; specific subgroups are more likely to be victimized. For example, youth who identify as a sexual minority are more likely to be victims of traditional forms of bullying than their heterosexual friends. There has been less research, however, on population subgroups and the likelihood of becoming a victim of cyber aggression. In exploring this topic, this chapter examines several questions including, “How important is the amount of time spent online as an intermediate variable in predicting whether an individual will become a victim of cyber aggression?” and “Does sexual orientation impact the likelihood of being a victim of cyberaggression above and beyond the amount of time spent online?” Multivariate statistical methods and survey data from the Pew Research Center for the year 2014 was used in this analysis.

Sensitivity analysis for unobserved confounding in causal mediation analysis allowing for effect modification, censoring and truncation

Causal mediation analysis is used to decompose the total effect of an exposure on an outcome into an indirect effect, taking the path through an intermediate variable, and a direct effect. To estimate these effects, strong assumptions are made about unconfoundedness of the relationships between the exposure, mediator and outcome. These assumptions are difficult to verify in a given situation and therefore a mediation analysis should be complemented with a sensitivity analysis to assess the possible impact of violations. In this paper we present a method for sensitivity analysis to not only unobserved mediator-outcome confounding, which has largely been the focus of previous literature, but also unobserved confounding involving the exposure. The setting is estimation of natural direct and indirect effects based on parametric regression models. We present results for combinations of binary and continuous mediators and outcomes and extend the sensitivity analysis for mediator-outcome confounding to cases where the continuous outcome variable is censored or truncated. The proposed methods perform well also in the presence of interactions between the exposure, mediator and observed confounders, allowing for modeling flexibility as well as exploration of effect modification. The performance of the method is illustrated through simulations and an empirical example.

The Role of Organizational Culture in Establishing Employee Engagement through Work Attitude at PT. Sapta Sentosa Jaya Abadi

PT Sapta Sentosa Jaya Abadi is a company engaged in the plantation sector which is currently focusing on developing the quality of human resources, because the role of human resources is very vital in the production and quality of Fresh Fruit Bunches and Crude Palm Oil. However, company have problems in HR management related to Employee Engagement problems, it is indicated by the low score of Employee Engagement, especially those at the non-managerial level. PT Sapta Sentosa Jaya Abadi has made various efforts in building Employee Engagement, among others, by cultivating corporate values in order to form a strong organizational culture in the company. Based on this phenomenon, this study aims to see and analyze the influence of Organizational Culture on Employee Engagement through Work Attitudes as an intermediate variable at PT Sapta Sentosa Jaya Abadi. The research methodology used is Path Analysis. The results showed that Organizational Culture has a positive and significant effect directly on Work Attitudes; Organizational Culture has a positive and significant effect directly on Employee Engagement; Work Attitude is directly proven to have a positive and significant effect on Employee Engagement; and Organizational Culture through Work Attitude indirectly has a positive and significant effect on Employee Engagement at PT Sapta Sentosa Jaya Abadi. Keywords: Organizational Culture, Work Attitudes, Employees Engagement, PT Sapta Sentosa Jaya Abadi.

Design and Dynamic Modeling of a 3-RPS Compliant Parallel Robot Driven by Voice Coil Actuators

In order to increase the driving force of the voice coil actuator while reducing its size and mass, the structural parameters of the coil and magnet in the actuator are optimized by combing Biot–Savart law with Lagrangian interpolation. A 30 mm × 30 mm × 42 mm robot based on a 3-RPS parallel mechanism driven by voice coil actuators is designed. The Lagrangian dynamic equation of the robot is established, and the mapping relationship between the driving force and the end pose is explored. The results of dynamic analysis are simulated and verified by the ADAMS software. The mapping relationship between the input current and the end pose is concluded by taking the driving force as the intermediate variable. The robot can bear a load of 10 g. The maximum axial displacement of the robot can reach 9 mm, and the maximum pitch angle and return angle can reach 40 and 35 degrees, respectively. The robot can accomplish forward movement through vibration, and the maximum average velocity can reach 4.1 mm/s.

Will You Cross the Threshold for Me?

In this work, we propose generic and novel side-channel assisted chosenciphertext attacks on NTRU-based key encapsulation mechanisms (KEMs). These KEMs are IND-CCA secure, that is, they are secure in the chosen-ciphertext model. Our attacks involve the construction of malformed ciphertexts. When decapsulated by the target device, these ciphertexts ensure that a targeted intermediate variable becomes very closely related to the secret key. An attacker, who can obtain information about the secret-dependent variable through side-channels, can subsequently recover the full secret key. We propose several novel CCAs which can be carried through by using side-channel leakage from the decapsulation procedure. The attacks instantiate three different types of oracles, namely a plaintext-checking oracle, a decryptionfailure oracle, and a full-decryption oracle, and are applicable to two NTRU-based schemes, which are NTRU and NTRU Prime. The two schemes are candidates in the ongoing NIST standardization process for post-quantum cryptography. We perform experimental validation of the attacks on optimized and unprotected implementations of NTRU-based schemes, taken from the open-source pqm4 library, using the EM-based side-channel on the 32-bit ARM Cortex-M4 microcontroller. All of our proposed attacks are capable of recovering the full secret key in only a few thousand chosen ciphertext queries on all parameter sets of NTRU and NTRU Prime. Our attacks, therefore, stress on the need for concrete side-channel protection strategies for NTRUbased KEMs.

Application of Health Belief Model Theory on Prevention of Stunting in Toddlers Through Nutritional Behavior

Stunting is a chronic condition that describes stunted growth due to long-term malnutrition. Incidence of stunting is caused by not optimal nutrition. The purpose of this study in general was to find the effect of the Health Belief Model theory on effort to prevent stunting in toddlers through nutritional fulfillment behavior. The research is a quantitative study with an observational method and a cross sectional approach. The sample was 243 stunting mothers. The independent variables are perceived susceptibility, severity, barriers, cues to action, perceived benefit and self efficacy. Nutritional fulfillment behavior as an intermediate variable and stunting prevention as a dependent variable. The result show that simultaneously there was an effect of variabel X on Y with a significance value of 0,000 and a large effect of 10,2%. And simultaneously shows that there is an effect of variable X and Y of Z with a significance value of 0,000 and a large effect of 12,8%. Data analysis used path analysis. Simultaneousy, there is an effect of the application of Health belief model theory on effort to prevent stunting in toddlers through nutritional fulfillment behavior.