Comments on “Editorial: fuzzy models-what are they andwhy?”

In the editorial by J.C. Bezdek (ibid., p.1), an example is presented to demonstrate differences between fuzzy membership and probability. The authors argue that probability can be used in a way much more closely analogous to this use of fuzzy membership, weakening the argument for the latter     

Optical signal routing using emission packet positioning of semiconductor heterostructure

We present a novel optical switching technique utilizing emission packet positioning of semiconductor heterostructure. A modulation-doped p-AlGaAs-GaAs heterostructure is employed to control spontaneous emission packet positioning with electric fields. Emission packets generated by optical input signals are brought over 150 /spl mu/m with electric fields, so the output fibers can detect the emission intensity as signals. The first-order analysis indicates that the drift velocity of minority electrons in GaAs limits the detectable maximum data rate and nanoseconds timescale signal routing operation at 20 Gb/s is possible at an electron drift velocity of 2/spl times/10/sup 7/ cm/s.     

Changes in and stability of hostile characteristics: Results from a 4-year longitudinal study of children.

Changes in and stability of hostility characteristics and their relationship to age, sex, and family support were examined among 108 10–18 yr olds in a 4-yr longitudinal study. Clinical ratings of Structured Interview potential for hostility, self-reported MMPI-derived hostile attitudes, and perceptions of family support were obtained at study entry and at follow-up when Ss were aged 15–21 yrs. Results showed relative stability of hostility rankings across 4 yrs, with males being more hostile than females. Both sexes increased in hostility over time, with the greatest increase in Ss who perceived low family support at follow-up and whose parents perceived high family support at study entry. Results are consistent with notions that early signs of hostility are risk factors for later development of coronary disease and that family environment influences development of hostility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cumulative Sum Control Charts for Monitoring Weibull‐distributed Time Between Events

The Weibull distribution can be used to effectively model many different failure mechanisms due to its inherent flexibility through the appropriate selection of a shape and a scale parameter. In this paper, we evaluate and compare the performance of three cumulative sum (CUSUM) control charts to monitor Weibull‐distributed time‐between‐event observations. The first two methods are the Weibull CUSUM chart and the exponential CUSUM (ECUSUM) chart. The latter is considered in literature to be robust to the assumption of the exponential distribution when observations have a Weibull distribution. For the third CUSUM chart included in this study, an adjustment in the design of the ECUSUM chart is used to account for the true underlying time‐between‐event distribution. This adjustment allows for the adjusted ECUSUM chart to be directly comparable to the Weibull CUSUM chart. By comparing the zero‐state average run length and average time to signal performance of the three charts, the ECUSUM chart is shown to be much less robust to departures from the exponential distribution than was previously claimed in the literature. We demonstrate the advantages of using one of the other two charts, which show surprisingly similar performance. Copyright © 2014 John Wiley & Sons, Ltd.     

Control Charts for Monitoring Linear Profiles with Within‐Profile Correlation Using Gaussian Process Models

Profile monitoring is the utilization of control charts for checking the stability of the quality of a product over time when the product quality is characterized by a function at each time point. Most existing control charts for monitoring profiles are based on the assumption that the observations within each profile are independent of each other, which is often invalid in practice. Successive measurements within profiles often exhibit spatial or serial correlation. This paper focuses on Phase II linear profile monitoring when within‐profile data are correlated. A Gaussian process model is used to describe the within‐profile correlation (WPC). Two Shewhart‐type multivariate control charts are proposed to monitor the linear trend term and the WPC separately in Phase II. Our proposed approaches are compared with alternative methods through numerical simulations in which different in‐control WPCs are considered. Simulation studies show that the proposed control charts are sensitive to changes in the linear trend term when the correlation is strong and effective in detecting large shifts in the WPC. Finally, an example is given to illustrate the implementation of our proposed control charts. Copyright © 2013 John Wiley & Sons, Ltd.     

Japan's new basic energy plan

In June 2010, the Japanese cabinet adopted a new Basic Energy Plan (BEP). This was the third such plan that the government has approved since the passage of the Basic Act on Energy Policy in 2002, and it represents the most significant statement of Japanese energy policy in more than four years, since the publication of the New National Energy Strategy (NNES) in 2006. Perhaps more than its predecessors, moreover, the new plan establishes a number of ambitious targets as well as more detailed measures for achieving those targets. Among the targets are a doubling of Japan's “energy independence ratio,” a doubling of the percentage of electricity generated by renewable sources and nuclear power, and a 30 percent reduction in energy-related CO₂ emissions, all by 2030. This paper explains the origins of the 2010 BEP and why it was adopted. It then describes the content of the plan and how it differs from the NNES. A third section analyzes the appropriateness of the new goals and targets contained in the BEP and their feasibility, finding that achievement of many of the targets was likely to be quite challenging even before the March 2011 earthquake, tsunami, and nuclear crisis.     

Tunability of YBa2Cu3O7/SrTiO3 hetero-structures for microwave filters : growth parameter optimisation of the titanate layer

Heterostructures have been grown of YBa ₂ Cu ₃ O ₇ /SrTiO ₃ deposited on LaAlO ₃ substrates by PLD. RHEED observations were made during deposition of the ferroelectric layer and the parameters were optimised to produce near 2D growth. After XRD and surface resistance measurements, these samples were then patterned into tunable resonators comprising of interdigital combs. In these structures the tunability is achieved as a result of the change in the dielectric constant of the ferroelectric material between the combs when a DC voltage is applied. In excess of 500 MHz of tuning in the resonant frequency of the device has been observed, and from these data it has been possible to derive values of _r and tan for the ferroelectric layer which can then be used to design and model tunable microwave devices.