Chatter, process damping, and chip segmentation in turning: A signal processing approach

An increasing number of aerospace components are manufactured from titanium and nickel alloys that are difficult to machine due to their thermal and mechanical properties. This limits the metal removal rates that can be achieved from the production process. However, under these machining conditions the phenomenon of process damping can be exploited to help avoid self-excited vibrations known as regenerative chatter. This means that greater widths of cut can be taken so as to increase the metal removal rate, and hence offset the cutting speed restrictions that are imposed by the thermo-mechanical properties of the material. However, there is little or no consensus as to the underlying mechanisms that cause process damping. The present study investigates two process damping mechanisms that have previously been proposed in the machining literature: the tool flank/workpiece interference effect, and the short regenerative effect. A signal processing procedure is employed to identify flank/workpiece interference from experimental data. Meanwhile, the short regenerative model is solved using a new frequency domain approach that yields additional insight into its stabilising effect. However, analysis and signal processing of the experimentally obtained data reveals that neither of these models can fully explain the increases in stability that are observed in practice. Meanwhile, chip segmentation effects were observed in a number of measurements, and it is suggested that segmentation could play an important role in the process-damped chatter stability of these materials

Implementation of Serious Games Inspired by Baluran National Park to Improve Students\u27 Critical Thinking Ability

The purpose of this study is to implement Baluran National Park-based Serious Game to enhance the students\u27 creative thinking skill and motivation to learn. The subject of the study were 60 students of SMP Negeri 1 Asembagus, Situbondo regency. The sample was divided into three groups. Two groups were chosen as experimental classes and the other group as the control class. Both of the experimental groups were given treatment using serious game based on Baluran National Park. The instruments used were observation sheet, pre-test, and post-test. Baluran National Parks-based serious game was effective in improving the students\u27 creative thinking skill and motivation to learn science subjects

Split-gate quantum point contacts with tunable channel length

We report on developing split-gate quantum point contacts (QPCs) that have a tunable length for the transport channel. The QPCs were realized in a GaAs/AlGaAs heterostructure with a two- dimensional electron gas (2DEG) below its surface. The conventional design uses 2 gate fingers on the wafer surface which deplete the 2DEG underneath when a negative gate voltage is applied, and this allows for tuning the width of the QPC channel. Our design has 6 gate fingers and this provides additional control over the form of the electrostatic potential that defines the channel. Our study is based on electrostatic simulations and experiments and the results show that we developed QPCs where the effective channel length can be tuned from about 200 nm to 600 nm. Length-tunable QPCs are important for studies of electron many-body effects because these phenomena show a nanoscale dependence on the dimensions of the QPC channel

N-player quantum games in an EPR setting

The $N$-player quantum game is analyzed in the context of an Einstein-Podolsky-Rosen (EPR) experiment. In this setting, a player's strategies are not unitary transformations as in alternate quantum game-theoretic frameworks, but a classical choice between two directions along which spin or polarization measurements are made. The players' strategies thus remain identical to their strategies in the mixed-strategy version of the classical game. In the EPR setting the quantum game reduces itself to the corresponding classical game when the shared quantum state reaches zero entanglement. We find the relations for the probability distribution for $N$-qubit GHZ and W-type states, subject to general measurement directions, from which the expressions for the mixed Nash equilibrium and the payoffs are determined. Players' payoffs are then defined with linear functions so that common two-player games can be easily extended to the $N$-player case and permit analytic expressions for the Nash equilibrium. As a specific example, we solve the Prisoners' Dilemma game for general $N \ge 2$. We find a new property for the game that for an even number of players the payoffs at the Nash equilibrium are equal, whereas for an odd number of players the cooperating players receive higher payoffs.Comment: 26 pages, 2 figure

Analyzing three-player quantum games in an EPR type setup

We use the formalism of Clifford Geometric Algebra (GA) to develop an analysis of quantum versions of three-player non-cooperative games. The quantum games we explore are played in an Einstein-Podolsky-Rosen (EPR) type setting. In this setting, the players' strategy sets remain identical to the ones in the mixed-strategy version of the classical game that is obtained as a proper subset of the corresponding quantum game. Using GA we investigate the outcome of a realization of the game by players sharing GHZ state, W state, and a mixture of GHZ and W states. As a specific example, we study the game of three-player Prisoners' Dilemma.Comment: 21 pages, 3 figure

An Exploratory Framework for Intelligent Labelling of Fault Datasets

Software fault prediction (SFP) has become a pivotal aspect in realm of software quality. Nevertheless, discipline of software quality suffers the starvation of fault datasets. Most of the research endeavors are focused on type of dataset, its granularity, metrics used and metrics extractors. However, sporadic attention has been exerted on development of fault datasets and their associated challenges. There are very few publicly available datasets limiting the possibilities of comprehensive experiments on way to improvising the quality of software. Current research targets to address the challenges pertinent to fault dataset collection and development if one is not available publicly. It also considers dynamic identification of available resources such as public dataset, open-source software archieves, metrics parsers and intelligent labeling techniques. A framework for dataset collection and development process has been furnished along with evaluation procedure for the identified resources

Coevolution of quantum and classical strategies on evolving random networks

We study the coevolution of quantum and classical strategies on weighted and directed random networks in the realm of the prisoner’s dilemma game. During the evolution, agents can break and rewire their links with the aim of maximizing payoffs, and they can also adjust the weights to indicate preferences, either positive or negative, towards their neighbors. The network structure itself is thus also subject to evolution. Importantly, the directionality of links does not affect the accumulation of payoffs nor the strategy transfers, but serves only to designate the owner of each particular link and with it the right to adjust the link as needed. We show that quantum strategies outperform classical strategies, and that the critical temptation to defect at which cooperative behavior can be maintained rises, if the network structure is updated frequently. Punishing neighbors by reducing the weights of their links also plays an important role in maintaining cooperation under adverse conditions. We find that the self-organization of the initially random network structure, driven by the evolutionary competition between quantum and classical strategies, leads to the spontaneous emergence of small average path length and a large clustering coefficient.Qiang Li, Azhar Iqbal, Matjaž Perc, Minyou Chen, Derek Abbot

Pengaruh Stres Kerja Lingkungan, Organisasional, Dan Personal Terhadap Kepuasan Kerja (Studi Pada Karyawan Dinas Ketenagakerjaan Dan Transmigrasi Kota Malang)

The purpose of this research is to know the condition variables and to explain the environment job stress effect on the job satisfaction, to explain the organizational job stress effect on the job satisfaction, and to explain the personal job stress effect on the job satisfaction. The population used in this research is all employees Dinas Ketenagakerjaan dan Transmigrasi Kota Malang totaling 45 people. The results of the descriptive analysis showed that environment job stress, organizational job stress, and personal job stress at Dinas Ketenagakerjaan dan Transmigrasi Kota Malang are low, while the employee job satisfaction is high. Based on the result of the infrential analysis is known there is a negative and significant impact on of the environment job stress to the job satisfaction. There is a negative and significant impact on of the organizational job stress to the job satisfaction. There is a negative and significant impact on of the personal job stress to the job satisfaction

Using social identity to promote health:the impact of group memberships on health in the context of obesity

As contemporary approaches to addiction treatment are evolving from models predominantly focused on acute bio-psychosocial stabilisation to models similar to managing chronic diseases such as diabetes and high blood pressure (White, 2009), the importance of communities of support becomes more central. The role of social support groups in recovery from addiction (Best et al., 2016), and other health conditions (Jetten, Haslam, & Haslam, 2012) has long been recognised and extensively researched. There has been a move from models predicated on an ‘individual struggle’ to a shared recovery process, that is, from an individual-focused approach to change to more socially oriented alternatives, not only regarding treat - ment per se, but also in how support for recovery is conceptualised (Beckwith, Bliuc, & Best, 2016; White, 1998). Recent definitions of recovery from addiction characterise recovery as a “process of change through which individuals improve their health and wellness, live self-directed lives, and strive to reach their full potential” (Substance Abuse and Mental Health Services Administration, 2012). SAMHSA’s working definition of recovery encompasses four dimensions necessary to support recovery – health, home, purpose and community – incorporating the recognition that, during this process, social support is paramount (Betty Ford Institute, 2007)