Bending vibration prediction of orthotropic plate with wave-based method

A novel numerical predictive approach for steady-state response of thin orthotropic plate is presented based on wave-based method (WBM) that is applied in bending vibration prediction of thin and thick plate in mid-frequency range. The wavenumber parameters for orthotropic material and the particular solution of an infinite orthotropic plate with Fourier transform are derived. The proposed method is validated by numerical examples with simply supported boundary and clamped boundary. The compared result shows that the computational accuracy and efficiency of WBM is significantly higher than element based method, which is the ability of WBM for mid-frequency problems. The predictive ability of WBM is extended to process the dynamic response of orthotropic plate

Instability Process Model Test for Bedding Rock Slope with Weak Interlayer under Different Rainfall Conditions

The instability process of bedding rock slope with weak interlayer may be induced under rainfall infiltration conditions. Due to this, we conducted a research of model test for the instability process, based on the similarity theory. With use of the recent 50 years’ rainfall data of Changsha, China, we analyzed the seepage characteristics, mechanical characteristics, and deformation laws of the slope under the conditions of long-time heavy rain and short-time rainstorm, respectively. The test results show that the original seepage characteristics of the slope were changed by the existence of weak interlayer, presented the “double seepage” effect, resulted in the seepage characteristics of rock and soil in the shallow layer and weak interlayer of the slope showed a sickle “Γ” distribution, and the adjacent rock layer presented a curve-type “S” distribution. With the increase of rainfall duration, the weak interlayer gradually became muddy and softened, and then the plastic flow zone was formed locally. The stress concentration phenomenon was gradually generated in the weak interlayer due to the influence of the gravitational field of the upper rock mass. The large infiltration of rainwater led to the phenomenon of plastic flow extrusion of the slope at the weak interlayer extrusion. With the further penetration of the tensile cracks in the upper part of the weak interlayer, the slope had a large settlement displacement and gradually formed sliding shear deformation along the weak structural plane. Under the condition of equal rainfall amount, the condition of long-time heavy rain has a greater influence on the stability of the bedding rock slope with weak interlayer than that of short-time rainstorm. The failure form of slope could be divided into four stages: prechange stage, interlayer extrusion stage, slip-pull-fracture stage and plastic flow-shear failure stage

The source localization technique based on improved functional beamforming using a virtual array

Beamforming have become a popular technique to identify sound source. The most common application is conventional beamforming, but it has low resolution and requires a large number of microphones at low frequency. To overcome this problem, an improved functional beamforming method based on “virtual array” and the relative spectral matrix is introduced. Firstly, the relative complex pressures of the sound field can be acquired by “virtual array” with one scanning microphone and a fixed reference microphone. Thereby, a relative spectral matrix of the relative complex pressures measured can be obtained. Then the improved functional beamforming method with order v is developed based on the relative spectral matrix. And the resolution of the improved method can be modified by increased the number of order v. but it also can be improved by changing virtual microphones. This property allows widening the scope of this interesting beamforming method

Application of wave based method for predicting the response of coupled vibro-acoustic system with unconstrained damping layer

The Wave Based Method (WBM) is a deterministic prediction method that is computational efficiency as compared to other deterministic prediction techniques in mid-frequency problems. This paper discusses the application of WBM for predicting the dynamic displacement of plate with an unconstrained damping layer based on Kirchhoff theory. Further, the prediction of acoustic response of the coupled vibro-acoustic system with unconstrained damping is realized on the use of WBM. A numerical example is introduced, and the comparison of numerical result obtained by WBM and FEM is acquired. It is seen that the WBM is applicable for vibro-acoustic system with unconstrained damping and is expected to yield faster and more accurate predictions. The limitation of the method caused by simplify hypothesis is described in combination with modelling ways and numerical results

Analysis of partial-body and whole-body static sitting comfort

The whole-body comfort sensation was moderately to highly correlated with local body part comfort sensation in both sitting and driving, in order to understand what exact relationship exists between them, the seating comfort evaluations under the stimulus of four body parts (i.e. backs, waist, hips and thighs) were carried out for 15 subjects separately, subjective ratings on both partial-body and whole-body comfort are derived under different conditions. Impact factor (IF) of the partial-body comfort to whole-body comfort is calculated by the linear regression method, and the main variables are obtained by the stepwise regression algorithm. The most significant local body part in influencing whole body comfort is found at the region of hips, followed by backs, waist and hips. With impact factor analysis on partial body comfort, the results show that the local comfort feeling of waist is most potential to be influenced by other body parts, while the comfort sensitivity of thighs is the lowest

The improved separation method of coherent sources with two measurement surfaces based on statistically optimized near-field acoustical holography

A technique for separating coherent sources measured by two parallel arrays is proposed. The two measurement surfaces located in the opposite directions of the coherent sources. Similar to separate the aim source from background noise, this method can separate the single source from coherent sources, which makes the sound field information of single source in complex environment more accurate. Such improved separation method based on statistically optimized near-field acoustical holography, according to the sound pressure relationship between measurement surfaces and reconstruction surfaces to separate the sources, reduces the measurement data and obtains higher precision of reconstruction. The present paper uses the improved separation method to obtain the single source results from numerical simulations, gives the relative reconstruction errors with frequency from 100 Hz to 1400 Hz, and practical measurement

Thorough Financial Analysis for a better Risk Management

In recent years, the significance of financial risk management has been progressively highlighted by the organizations, especially after the financial crisis of 2007-08.  Due to inadequate information or negligence in identifying the risk, several investment companies face higher risks associated with their investment, which leads to financial distress or bankruptcy. This article aims towards finding measures for the identification, evaluation, analysis, and monitoring of risks that can be implemented by the various firms to cope up with their internal financial risks. It is because to generate higher returns on investment it is important for the organization to understand the risks associated with the investment and manage them accordingly. Therefore, to manage the financial risks associated with the investment, the organization needs to go through the risk management process which involves risk identification, risk analysis and evaluation, risk response and risk monitoring. Moreover, we will be discussing on the three categories of risk named as profitability, solvency and liquidity, which are one of the most important internal financial risks that medium sized investment company experiences

Investing in the Emerging Economies (The Next -11 Countries) and How Do These Countries

The Next 11 (N-11 countries) is a list of fast-growing countries with promising outlooks for investment and future growth. These countries are Bangladesh, Egypt, Indonesia, Iran, Mexico, Nigeria, Pakistan, Philippines, Turkey, South Korea and Vietnam. This paper discuss about investing in these countries and how political risk affect on

Circadian rhythm of Liposcelis entomophila and Liposcelis paeta in paddy warehouse: Presentation

Booklice is a small but serious stored grain pest, and understanding the circadian rhythm of booklice help to control. In this study, circadian activity of booklice were monitored with sticky traps in the grain bulk surfaces of two warehouses stored paddy rice in two different provinces in China. The results showed that the species of booklice were different and were Liposcelis entomophila, and Liposcelisp paeta for Nanning’s and Zhanjiang’s warehouses respectively. In term of L.entomophila, its activity intensity gradually decreased from 0 am to 12 pm and reached the lowest level of daily activity at 12pm. After this, there was a steady and straight upward trend, and the peak of its activity intensity is reached at 8 pm. Its circadian activity trend can be represented as: y = - 0.971x3 + 21.88x2 - 139.5x + 353.4(x: time; y: quantity of booklice). Over the same period, the activity intensity of L.paeta varied greatly. It gradually increased, reached a peak at 8 am, dropped dramatically at 12 pm and then climbed the second peak at 6 pm.Booklice is a small but serious stored grain pest, and understanding the circadian rhythm of booklice help to control. In this study, circadian activity of booklice were monitored with sticky traps in the grain bulk surfaces of two warehouses stored paddy rice in two different provinces in China. The results showed that the species of booklice were different and were Liposcelis entomophila, and Liposcelisp paeta for Nanning’s and Zhanjiang’s warehouses respectively. In term of L.entomophila, its activity intensity gradually decreased from 0 am to 12 pm and reached the lowest level of daily activity at 12pm. After this, there was a steady and straight upward trend, and the peak of its activity intensity is reached at 8 pm. Its circadian activity trend can be represented as: y = - 0.971x3 + 21.88x2 - 139.5x + 353.4(x: time; y: quantity of booklice). Over the same period, the activity intensity of L.paeta varied greatly. It gradually increased, reached a peak at 8 am, dropped dramatically at 12 pm and then climbed the second peak at 6 pm