A concept of water usage efficiency to support water reduction in manufacturing industry

Increasing pressures on freshwater supplies, continuity of supply uncertainties, and costs linked to legislative compliance, such as for wastewater treatment, are driving water use reduction up the agenda of manufacturing businesses. A survey is presented of current analysis methods and tools generally available to industry to analyze environmental impact of, and to manage, water use. These include life cycle analysis, water footprinting, strategic planning, water auditing, and process integration. It is identified that the methods surveyed do not provide insight into the operational requirements from individual process steps for water, instead taking such requirements as a given. We argue that such understanding is required for a proactive approach to long-term water usage reduction, in which sustainability is taken into account at the design stage for both process and product. As a first step to achieving this, we propose a concept of water usage efficiency which can be used to evaluate current and proposed processes and products. Three measures of efficiency are defined, supported by a framework of a detailed categorization and representation of water flows within a production system. The calculation of the efficiency measures is illustrated using the example of a tomato sauce production line. Finally, the elements required to create a useable tool based on the efficiency measures are discussed

TESTING THE INCOMPLETE ARBITRATE HYPOTHESIS: EVIDENCE FROM AUSTRALIAN WHOLESALE SUPERANNUATION FUNDS

This paper tests the efficiency of capital markets when information is costly to obtain by analysing the performance of Australian wholesale superannuation funds specialising in the management of domestic equity portfolios from 1991 through 1999. Using a fund regression approach, the paper finds evidence that is consistent with an incomplete arbitrage function, with investment managers generating returns sufficiently high to compensate them for the increased costs of active asset selection. Risk-adjusted returns in the Australian superannuation fund industry, net of management fees and expenses, are comparable to the returns from a passive asset selection policy.Superannuation funds, Australia

A robust sequential hypothesis testing method for brake squeal localisation

This contribution deals with the in situ detection and localisation of brake squeal in an automobile. As brake squeal is emitted from regions known a priori, i.e., near the wheels, the localisation is treated as a hypothesis testing problem. Distributed microphone arrays, situated under the automobile, are used to capture the directional properties of the sound field generated by a squealing brake. The spatial characteristics of the sampled sound field is then used to formulate the hypothesis tests. However, in contrast to standard hypothesis testing approaches of this kind, the propagation environment is complex and time-varying. Coupled with inaccuracies in the knowledge of the sensor and source positions as well as sensor gain mismatches, modelling the sound field is difficult and standard approaches fail in this case. A previously proposed approach implicitly tried to account for such incomplete system knowledge and was based on ad hoc likelihood formulations. The current paper builds upon this approach and proposes a second approach, based on more solid theoretical foundations, that can systematically account for the model uncertainties. Results from tests in a real setting show that the proposed approach is more consistent than the prior state-of-the-art. In both approaches, the tasks of detection and localisation are decoupled for complexity reasons. The localisation (hypothesis testing) is subject to a prior detection of brake squeal and identification of the squeal frequencies. The approaches used for the detection and identification of squeal frequencies are also presented. The paper, further, briefly addresses some practical issues related to array design and placement. (C) 2019 Author(s)

Sensitivity and Linearity of Superconducting Radio-Frequency Single-Electron Transistors: Effects of Quantum Charge Fluctuations

We have investigated the effects of quantum fluctuations of quasiparticles on the operation of superconducting radio-frequency single-electron transistors (RF-SETs) for large values of the quasiparticle cotunneling parameter $\alpha=8E_{J}/E_{c}$, where $E_{J}$ and $E_{c}$ are the Josephson and charging energies. We find that for $\alpha>1$, subgap RF-SET operation is still feasible despite quantum fluctuations that renormalize the SET charging energy and wash out quasiparticle tunneling thresholds. Surprisingly, such RF-SETs show linearity and signal-to-noise ratio superior to those obtained when quantum fluctuations are weak, while still demonstrating excellent charge sensitivity.Comment: Submitted to Phys. Rev. Let

String spectra near some null cosmological singularities

We construct cosmological spacetimes with null Kasner-like singularities as purely gravitational solutions with no other background fields turned on. These can be recast as anisotropic plane-wave spacetimes by coordinate transformations. We analyse string quantization to find the spectrum of string modes in these backgrounds. The classical string modes can be solved for exactly in these time-dependent backgrounds, which enables a detailed study of the near singularity string spectrum, (time-dependent) oscillator masses and wavefunctions. We find that for low lying string modes(finite oscillation number), the classical near-singularity string mode functions are non-divergent for various families of singularities. Furthermore, for any infinitesimal regularization of the vicinity of the singularity, we find a tower of string modes of ultra-high oscillation number which propagate essentially freely in the background. The resulting picture suggests that string interactions are non-negligible near the singularity.Comment: Latex, 30pgs; v2. minor clarifications, references adde

A study on Laparoscopic Vs open appendectomy: A prospective comparative case series.

OBJECTIVES: 1. To compare the operative difficulties in terms of operating time between laparoscopic and open appendectomies. 2. To prove the effectiveness of either of the procedures in reducing the postoperative morbidity in terms of: a) Postoperative pain and analgesic use. b) Return of bowel function. c) The resumption of liquid and subsequent solid diet. d) Rate of infection, both surgical site and intra-abdominal infections. e) Number of days of hospital stay. f) The number of days to return to near normal work. MATERIALS AND METHODS: MATERIALS: All patients presenting to the emergency department and outpatient department with acute appendicitis. METHODOLOGY: A record of all patients including age, sex, clinical history relevant and physical examination findings, past illnesses and prior major abdominal surgeries. A detailed consent explaining both the open and laparoscopic approaches and the procedure and complications involved with each approach, the postoperative recovery and morbidity was obtained. Inclusion Criteria: All patients presenting with right lower quadrant pain or periumbilical pain migrating to the right lower quadrant with nausea and /or vomiting and fever >38 deg C and / or Leukocytosis > 10,000 cells /cu.mm, right lower quadrant tenderness and / or guarding on physical examination or with graded compression sonographic probe tenderness or other diagnostic evidence of appendicitis. Exclusion Criteria: 1. Paediatric patients (< 12 yrs), 2. Pregnant women, 3. Comorbid illness, 4. Contraindications to general anaesthesia / laparoscopy, 5. Patients with other intra-abdominal pathologies presenting as acute appendicitis found to be otherwise intra-operatively. STUDY GROUPS: 50 patients chosen matching the inclusion and exclusion criteria from both the open and laparoscopic appendectomy groups and analysed for outcome and various parameters assessed and compared. PROCEDURE: All patients resuscitated with i.v fluids and nil by mouth for eight hours prior procedure. A dose of prophylactic antibiotics with cefotaxime 1 g iv from the time of diagnosis every 12th hourly and in cases of suspected complications, additional gentamicin 80 mg iv 12th hrly and Metronidazole 500mg iv 8th hrly were added. CONCLUSION: To conclude, the use of minimal access surgery in appendicitis significantly reduces the morbidity than with the open approach. The use of laparoscopy for the management of appendicitis has significantly increased the diagnosis of other pathologies mimicking acute appendicitis particularly in the young female patients with co-existent or masquerading gynaecological pathology. This has also led to the decrease in the rate of the negative appendectomy

Dry sliding friction and wear behavior of hybrid glass - carbon fiber reinforced PA66/PTFE composites

The tribological response and the frictional effects in dry sliding wear behaviour of hybrid Glass –Carbon composites under the action of sliding load and sliding velocity was studied. The material systems considered for the investigation were PA66/PTFE blend (80/20 wt. %), Blend(PA66/PTFE)/10 wt.% short glass fiber (SGF), Blend (PA66/PTFE)/10 wt.% short carbon fiber (SCF) and Blend (PA66/PTFE)/10 wt.% SGF/10 wt.% SCF (GC).These composites were produced using melt mixing method through extrusion and followed by injection molding. The experimentation was conducted as per ASTM G99 method. The experimentation data revealed that the significant wear resistance was exhibited by Glass-Carbon hybrid composites under the action of all the test parameters. This is attributed to the hybrid effect of fibres which may restrict the early reaching of softening point of polymers thereby preventing melting wear. Further, the formation of uniform and defined transfer polymer substrate on the steel disc surface reduced the frictional effects. Further, Blend/SCF composites were better than Blend/SGF composites. The composites studied were sensitive to applied normal load compared to velocity. The combined matrix and fiber wear were credited to the critical wear volume loss. Fiber misalignment, matrix deformation, melting wear and fiber peeling were some of the failure mechanisms observed in the morphological study of hybrid composites through SEM images

LOW ALTITUDE AIRSHIPS FOR SEAMLESS MOBILE COMMUNICATION IN AIR TRAVEL

The Aviation Administration policy prohibits the use of mobile phones in Aircraft during transition for the reason it may harm their communication system due to Electromagnetic interference. In case the user wants to access cellular network at higher altitudes, base station access is a problem. Large number of channels are allocated to a single user moving at high speed by various Base Stations in the vicinity to service the request requiring more resources. Low Altitude Platforms (LAPs) are provided in the form of Base stations in the Airships with antennas projected upwards which has direct link with the Ground Station. LAPs using LongEndurance Multi-Intelligence Vehicle (LEMVs) equipped with an engine for mobility and stable positioning against rough winds are utilized. This paper proposes a system that allows the passengers to use their mobiles in Aircraft using LAPs as an intermediate system between Aircraft and Ground station. As the Aircraft is dynamic, it has to change its link frequently with the Airships, MANETs using AODV protocol is established in the prototype using NS2 to provide the service and the results are encouraging

Comparative Analysis of Velocity Measurements In Ducted Axial Fan

The paper deals with experimental investigation and comparative analysis of velocity measurements in ducted axial fan. Experiments were carried out to investigate the nature of velocity variations in a ducted axial fan at different throttle positions as a function of rotor speed employing both Pitot tube and Hot Wire Anemometer. Quantitative analyses of the magnitudes of velocity measured by a pitot tube as well as a hot wire anemometer are examined and various graphs have been plotted. The percentage errors of velocity level have been determined