Application of PCA-based hybrid Taguchi method for correlated multicriteria optimization of submerged arc weld: a case study

Fluid dispensing is a method by which fluid materials, such as epoxy, adhesive, and encapsulant, are delivered in a controlled manner in electronics packaging. This paper presents a brief review of past and recent developments in the modeling and control of the time-pressure fluid dispensing process. In particular, the characterization of the fluid flow behavior is addressed by reviewing several promising models from both time-independent and time-dependent perspectives. In the modeling of the time-pressure fluid dispensing process, various approaches for representing the flow rate of fluid dispensed and the profile of fluid formed on target are examined; and the issues involved are identified. In the control of time-pressure dispensing process, a brief review of various control methods is presented along with their limitations. The challenges associated with this control problem are also discussed. This paper is concluded with the recommendations of research in the future.     

Superferric quadrupoles for FAIR Super FRS energy buncher

The quadrupole magnets for FAIR Super FRS energy buncher have large usable aperture, high magnetic pole-tip field and high gradient field quality. The iron-dominated magnets with superconducting coils have to be used in this application. The NbTi coil, laminated iron, and support structure of about 22 tons is immersed in liquid helium. The 4.5 K helium chamber is completely covered with a thermal shield cooled by helium at 50–80 K on its outer and inner surface. The helium chamber and thermal shield is enclosed in a vacuum shell.The paper presents design details of the long quadrupole. Coupled thermal, magnetic and structural analysis was carried out to design the magnet iron, magnet coil, helium vessel and support links and ensure the required gradient field quality is achieved. The paper also presents the design of support links and outer vacuum chamber.     

Effect of Cryogenic Pre-Treatment on Breakage Characteristics of Rocks

Improvement of energy efficiency in comminution of rocks using various pretreatment methods is being explored worldwide. This paper presents experimental data on breakage characteristics of granite and sandstone using cryogenic pre-treatment. The samples were treated with varying duration of immersion in liquid nitrogen. Combined pretreatment using oven heating followed by quenching in liquid nitrogen were also explored. The results indicate that using cryogenic pretreatment uniaxial tensile strength of granite can be decreased by more than 40% while in uniaxial compressive strength about 28% reduction is possible. For sandstone as much as 33% reduction in uniaxial compressive strength was observed.

     

High‐Performance Nanocomposites of Sodium Carboxymethylcellulose and Graphene Oxide

High‐performance nanocomposites of NaCMC with GO are produced by solution casting. FESEM images reveal a good homogeneous dispersion of GO in the NaCMC matrix. The composite formation is facilitated by H‐bonding interaction between GO and NaCMC. T_g of the composites increases with increasing GO concentration. The storage modulus (G′) exhibits a maximum 174% increase over NaCMC at 1 wt% GO. The mechanical properties of the composites exhibit highest increase of tensile stress and Young's modulus of 188 ± 4% and 154 ± 11%, respectively, for 1 wt% GO. Analysis of Young's modulus (E_y) data using the Halpin‐Tsai equation suggests that the E_y data are close to the unidirectional orientation at >0.5 wt% GO, indicating more efficient load transfer at these compositions.

     

Third order lowpass Butterworth filter function realisation using CFA

A new realisation scheme for third order lowpass Butterworth filter function (BFF) using two CFA devices and few RC components is presented. The design equations utilise the transadmittance elements of the devices. The maximally flat response at select frequencies in the range 5 MHz ≤ f _o ≤ 30 MHz had been verified with PSPICE macromodel simulation and by hardware circuit implementation using the AD-844 device. The active sensitivities are quite low. The simulation result and the measured responses are included for f _o = 5.1 MHz and 22.2 MHz.     

Steganalysis of Network Packet Length Based Data Hiding

Recently, data hiding by modifying network parameters like packet header, payload, and packet length has become popular among researchers. Different algorithms have been proposed during the last few years which have altered the network packets in different ways to embed the data bits. Some of these algorithms modify the network packet length for embedding. Although most of the packet length based embedding schemes try to imitate the normal network traffic distribution, they have altered the statistical distribution of network packet lengths during embedding. These statistical anomalies can be exploited to detect such schemes. In this paper, a second order detection scheme for packet length based steganography has been proposed. A comprehensive set of experiments have been carried out to show that the proposed detection scheme can detect network packet length based steganography with a considerably high accuracy.     

谷氨酰胺转胺酶的功能性质及其在食品中的应用方法

本主要论述了微生物谷氨酰胺转胺酶的性质,功能及其在食品加工工业以及开发新型食品中的应用。     

Local antibiotic delivery systems for the treatment of osteomyelitis – A review

Osteomyelitis, an inflammatory process accompanied by bone destruction, is caused by infective microorganisms. The high success rates of antimicrobial therapy by conventional routes of administration in controlling most infectious diseases have not yet been achieved with osteomyelitis for several reasons. Local and sustained availability of drugs have proven to be more effective in achieving prophylactic and therapeutic outcomes. This review introduces osteomyelitis – its present options for drug delivery and their limitations, and the wide range of carrier materials and effective drug choices. Local drug delivery for osteomyelitis is a topic of importance for more than 20 years. Carrier materials used for local delivery of antibiotics may be classified as nonbiodegradable and biodegradable. Commonly used non biodegradable carrier materials are polymethyl methacrylate (PMMA), Acrylic beads, PMMA bone cement etc. and biodegradable materials are hydroxyapatite block, bioactive glass ceramics, collagen sponge, polylactide/ployglycolide implants. Both the systems release antibiotic at concentrations exceeding the minimum inhibitory concentrations (MICs) for the most common pathogens involved in osteomyelitis without causing any adverse systemic effects although non biodegradable beads are to be removed from the surgical site after completion of antibiotic release.     

In vitro and in vivo degradability,biocompatibility and antimicrobial characteristics of Cu added iron-manganese alloy

In recent years,iron(Fe)based degradable metal is explored as an alternative to permanent fracture fixation devices.In the present work,copper(Cu)is added in Fe-Mn system to enhance the degradation rate and antimicrobial properties.Fe-Mn-xCu(x=0.9,5 and 10 wt.％)alloys are prepared by the melting-casting-forging route.XRD analysis confirms austenite phase stabilization due to the presence of Mn and Cu.As predicted by Thermo-Calc calculations,Cu rich phase precipitations are noticed along the austen-ite grain boundaries.Degradation behaviours of Cu added Fe-Mn alloys are investigated through static immersion and electrochemical polarization where enhanced degradation is found for higher Cu added alloys.When challenged against E.Coli bacteria,the Fe-Mn-Cu alloy media extract shows a significant bac-tericidal effect compare to the base alloy.In vitro cytocompatibility studies,as determined using MG63 and MC3T3-E1 cell lines,indicate increased cell density as a function of time for all the alloys.When implanted in rabbit femur,the newly developed alloy does not show any kind of tissue necrosis around the implants.Better osteogenesis and higher new bone formation are observed with Fe-Mn-10Cu alloy as evident from micro-computed tomography(μ-CT)and fluorochrome labelling.     

Effect of weathering on physico-chemical properties and combustion behavior of an Indian thermal coal

International Journal of Coal Science & Technology - An open air stockpile of conical shape was formed with 3.5 m base diameter and 5 m height using 500 tons of...