Local Squeeze Research Articles

Local government fiscal squeeze, environmental regulation and firms’ polluting behavior: Evidence from China

Government fiscal capability is closely related to the environmental regulation policy, but few studies have considered the effect of local government fiscal squeeze on firms' environmental decisions. Adopting a sample of Chinese industrial firms between 2002 and 2012, we implement a difference-in-differences (DD) method to examine the influence of fiscal squeeze on firms’ polluting behavior. We find that fiscal squeeze leads to more sulfur dioxide emissions from firms. This effect is only significant on large-scale firms, private firms, firms whose taxes are collected by the local taxation bureaus (LTB), and firms in heavily polluting sectors. We further investigate the potential mechanism and find that, resulting from the fiscal squeeze, local governments seek to expand their tax base by relaxing environmental regulations. The results suggest that keeping fiscal revenue stable is conducive to improving air quality.

Revenue pressure of local governments and firm productivity: Evidence from a natural experiment in China

AbstractThis study investigates how the revenue pressure of local governments affects firm total factor productivity (TFP). To establish causality, we exploit a policy shock in China, that is, the cancellation of agricultural tax in 2005. Specifically, we document that governments suffering from sudden tax reduction substantially increase local firms' productivity in the subsequent periods. Furthermore, we use the difference‐in‐differences‐in‐differences approach to explore the potential channels through which the local fiscal squeeze improves firm productivity. Local firms increase capital and employment and adopt a higher capital‐to‐labour substitution for a higher TFP in response to the local governments' fiscal squeeze. We find that the effects of revenue pressure incentives on productivity are prominent in firms with low resource misallocation and high labour quality. Our finding suggests that local governments could improve firm productivity in response to fiscal revenue pressure by enhancing resource allocation efficiency and labour quality.

Mating Market and Dynamics of Union Formation

The paper investigates the relationship between structural partner market constraints and the timing and educational sorting of unions in Germany (1985–2018). We integrate the literature on the effect of the reversed gender gap in education on educational assortative mating, with a focus on mating dynamics and the measurement of the partner market over the life course. We concentrate on two particular educational groups, low-educated men and highly educated women, those with worsening mating prospects and more subject to experience hypogamous unions. Our results show that the local education-specific mating squeeze influences union formation, its timing, and educational sorting. Indeed, for the two groups, the increasing supply of highly educated women in the partner market increases the likelihood of remaining single or establishing an hypogamous union, where she is higher educated than he. In line with search theory, we find the effects of the mating squeeze to become particularly visible after people turn 30 years of age. This is true for the risk of remaining single and forming an hypogamous union. We underline the necessity to study assortative mating and union formation from a dynamic perspective, taking into account changing structural conditions during the partner search process.

Equidistant distribution loss for person re-identification

Person re-identification (re-id) is a technology that matches images of a certain pedestrian among non-overlapping cameras. Recently, many approaches based on deep learning have been studied comprehensively. Most of these methods try to learn discriminative pedestrian features via elaborated network architectures and one or multi loss functions to maximize inter-class separability and intra-class compactness. However, the class imbalance characteristics from the datasets are ignored, and the discriminative information cannot be completely exploited. In this paper, we propose a novel loss function termed as Equidistant Distribution Loss (EDL) to improve the imbalance problem that exists in re-id tasks. Specifically, we first normalize the learned features in the embedding layer and the weights in the last fully connected layer, so that both the features and the weights can be projected on a hypersphere space. After that, we directly impose an equidistance constraint among the weights to guide the learned features spread uniformly in the sphere space. The proposed EDL can effectively address the local squeeze or imbalance problem caused by imbalanced samples, making full use of feature space and profiting the performance. Extensive experiments on re-id datasets, including Market-1501, DukeMTMC-reID are conducted to demonstrate the preferable performance of the proposed method.

Microstructure and Properties of A356 Alloy Wheels Fabricated by Low-Pressure Die Casting with Local Squeeze

The low-pressure die-casting process (LPDC) is widely used in fabricating aluminum alloy automotive wheels. With good castability and mechanical properties, A356 alloys are important and common materials for LPDC wheels. However, in practical casting process, defects often appear, especially porosities in the wheel thick-walled parts (i.e., spoke) due to inadequate interdendritic feeding, which greatly decreases the mechanical properties. In this investigation, to deal with this problem, local squeeze (LS) was added in conventional LPDC to enhance the interdendritic feeding. The practical A356 alloy wheel castings were fabricated with different LS velocities and times. The quantitative characteristics of α-Al cells, Si particles, and porosities with and without the LS analyzed by optical microscope, scanning electron microscope, and 3D x-ray computed tomography were compared. Their effects on the tensile and impact properties were discussed. The results have shown that the LS can increase the cooling rate and feed shrinkage of spoke parts, hence resulting in finer grains and denser microstructure. In result, the properties of spoke parts were improved with the LS.

Influence of Local Squeeze Process on Shrinkage Defect Control for High Pressure Die Casting

Influence of Local Squeeze Process on Shrinkage Defect Control for High Pressure Die Casting

Study The Effect of Fruit Juice Extract Helianthus Tuberosus on Liver Function and as Antibacterial Agent

The Helianthus tuberosus , it is one of the important Tuberous plants . at present time Where this plant was used in the study , Precisely the juice fruit of Helianthus tuberosus , as were used widely in promoting immune system , stimulate blood circulation, controlling cholesterol , blood pressure, diabetes, muscle , preservation of food , Antibacterial , the Beautify skin and Biofuels. This study conducted on juice fruit Helianthus tuberous . it taken from different areas in Baghdad / Iraq . after Buy them from the local market , washed, dried and squeeze . this study aimed to identify the chemical compounds and trace elements in the Helianthus tuberosus juice using tests chemical differents , usage a measurement technique (GC-MS) ,and the FTIR spectrum. and their impact on the liver function of domestic birds and species of microorganisms , The study is giving that the juice of the fruit Helianthus Tuberosus is Acidic nature and near from the value acidic for water , The study showed that the extract contains a group of carbohydrate compounds, phenol compounds, tannins , resins, flavonoids, alkaloids, turbines, unsaturated fatty acids, polymers. and the Inulin compound. The Study showed the ability of juice Helianthus Tuberosus in concentration of 15%, increasing stimulate of SGPT levels and SGOT in serum (p <0.01), while the levels of ALP, LDL, TG were decreased (p <0.05), The study shows extracting of phenolic compounds in fruit juice Helianthus Tuberousus when TLC and HPLC used a mixture (water, chloroform , acetic acid) and by (3: 6: 1) . This mixture had effect on multi pigment (gram pigments) . The effect was more in Gram positive bacteria (Escherichia coli Pseudomonas aeruginosa, Salmonella typhimurium), but its effect was less in Gram negative bacteria (Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis). lastly the study giving , through the quantitative estimate of the chemical elements of the juice of the Helianthus Tuberosus fruit , contained some important minerals of different concentrations with a capacity of (ppm).the presence of these elements led to increased enzymatic effectiveness through increased support for building bone tissue and the process of activating enzymes transfer of oxygen in the blood and increase the flow of all metabolic processes in the body and that these jobs will give an over view of the work and effectiveness of the nature activity of some organs of our body.

Effect of Controlling Process Parameters on Shrinkage Porosity in Aluminum Die-Casting Rotor

Aluminum rotor prone to have many casting defects especially large amount of gas and shrinkage porosity, which caused eccentricity, loss and noise during motor operation. Many attempts have been made to develop methods of shrinkage porosity control, but still there are some problems to solve. In this research, the process of vacuum squeeze die casting is proposed for limitation of defects. The 6 pin point gated dies which were in capable of local squeeze at the end ring were used. Influences of filling patterns on HPDC were evaluated and the important process control parameters were high injection speed, squeeze length, venting and process conditions. By using local squeeze and vacuum during filling and solidification, air and shrinkage porosity were significantly reduced and the feeding efficiency at the upper end ring was improved 10%. As a result of controlling the defects, the dynamometer test showed improved motor efficiency by more than 4%.

A Method to set process parameters of local squeeze in HPDC

In HPDC processes, pressurization of the mushy regions via local squeeze pins and plunger during the intensification stage is very important to decrease porosity defects. In order to better understand the process and to be able to set the process parameters more properly, we developed a simulation code to solve the flow field of mushy regions and porosity formation based on the following main assumptions: 1) Local squeeze pins and plunger tip can be treated as pressure boundaries, while the squeeze pins are treated as moving boundaries. 2)The intensification and local squeeze pressure can propagate inside regions where the solid fraction is less than critical values. 3) In the pressurized regions, the cast metal is treated as a Newtonian fluid and both the solid and liquid flow together when the solid fraction is low, and the D'Arcy flow only exists when the solid fraction goes higher. 3) Only the liquid flows in the unpressurized regions, following the D'Arcy's law. 4) Porosities grow in elements when the pressure decreases below critical values depending on the element condition. The simulation was applied to HPDC castings and showed that the pressure-duration was similar to the measured one though the simulated pressure drop in the pressurized region was much smaller than the measured one. The pressure drop, pressure-duration and pin-penetration depth were discussed and the simulation seems to be helpful to determine local squeeze parameters. Future challenges are also discussed.

Evaluation of Porosity in Al Alloy Die Castings

Evaluation of Porosity in Al Alloy Die Castings Mechanical properties of an Al-alloy die casting depend significantly on its structural properties. Porosity in Al-alloy castings is one of the most frequent causes of waste castings. Gas pores are responsible for impaired mechanical-technological properties of cast materials. On the basis of a complex evaluation of experiments conducted on AlSi9Cu3 alloy samples taken from the upper engine block which was die-cast with and without local squeeze casting it can be said that castings manufactured without squeeze casting exhibit maximum porosity in the longitudinal section. The area without local squeeze casting exhibits a certain reduction in mechanical properties and porosity increased to as much as 5%. However, this still meets the norms set by SKODA AUTO a.s.

Effects of impact loads on point contact elastohydrodynamic lubrication films

The behaviours of point contact elastohydrodynamic lubrication (EHL) films under impact loads are investigated by direct observations using the optical interferometry technique. It has been found that when the initial impact gap is large, a central dimple is formed and the maximum film thickness occurs at the centre of the contact region. When the initial impact gap becomes small, a periphery dimple is generated and the maximum film thickness occurs at the contact periphery. When impact is applied to an oily Hertzian contact, the maximum film thickness of the periphery dimple is determined by the increasing rate of the Hertzian contact radius. The impact load under rolling/sliding conditions results in a crescent-shaped oil entrapment originally at the inlet of the EHL conjunction, which passes through the EHL conjunction approximately at the entrainment velocity. Some numerical results are also presented to show that the experimental observation in the periphery region is induced by the local squeeze effect.

Optimization of Casting Design for Automobile Transmission Gear Housing by 3D Filling and Solidification Simulation in Local Squeeze Diecasting Process

In the partial squeeze casting process, the filling behavior of liquid metal and solidification pattern in thick area have significant influence on the quality of casting products and die life. For the optimal casting design of automobile transmission gear housing, various analyses were performed in this study by using computer simulation code, MAGMAsoft and the simulation results were compared and analyzed with experimental results. By air pressure criteria, internal porosities caused by air entrap during the mold filling were predicted and reduced remarkably by modification of gating system. Also, optimal squeeze-time lag to apply partial squeeze pin in thick area was calculated and the castings was free from shrinkage defects with the result of solidification analysis. Consequently, casting design for automobile transmission gear housing was optimized and approved by Computer Tomography.

Development of Al-15%Si Hypereutectic Alloy Automotive Part by Local Squeeze and Vacuum Diecasting

A functional automotive part, reaction shaft support, was fabricated by local squeeze and vacuum Diecasting (LSVD) with light-weight Al-15%Si hypereutectic alloy which has good fluidity and excellent wear resistance. The effects of local squeezing pressure and time-lag of LSVD process on the microstructure of the product were investigated. Measurement of specific gravity with the change of local squeeze pressure and time-lag showed that the local squeezing effect can be increased by increasing squeeze pressure and decreasing time-lag. However, too high a squeeze pressure and too a low time-lag brought about insufficient squeezing effect due to instant movement to the squeeze plunger stroke end point. Through the combination of vacuum suction before melt injection and local squeezing after melt injection in LSVD process, light-weight Al-15%Si alloy reaction shaft support was successfully developed, resulting in excellent microstructural and mechanical properties

Occurrence of a Noncentral Dimple in Squeezing EHL Contacts

Previous studies about pure squeeze elastohydrodynamic lubrication (EHL) have disclosed a film profile with a central dimple. Two problems about pure squeeze EHL are numerically solved in this paper. One is for a very small initial impact gap, and the other is the response of a squeezed EHL conjunction under stepwise loads. None of them result in the familiar film with a central dimple, which can be attributed to the local squeeze effect generated in the periphery region. In the first problem, it has been found that when there is adequate oil present on the plate, with a decrease in the initial impact gap, a shallow circumferential dimple occurs at the periphery of the conjunction instead of the primary central dimple presented in previous studies. Correspondingly the minimum film thickness occurs at the central region. The effect of the initial impact velocity on the periphery dimple is also investigated. In the second problem, the response of a conjunction subjected to a prescribed stepwise load is studied. When the first step load is applied, a central dimple film is produced. When the applied load is increased with a second step load, a periphery dimple appears, similar to that in the first problem. The local squeeze effect for the present numerical periphery dimple has been observed in previous experiments under similar conditions.

Physics of ultra-thin surface films on molecularly smooth surfaces

This paper investigates the physics of ultra-thin surface films in nano-scale counterformal conjunctions. A novel approach is proposed in which the transient behaviour of the fluid film is integrated with the contact mechanics of the approaching bodies. The method predicts film thickness and pressure distribution, as well as local elastic deflection and resulting sub-surface stress tensor. It is found that inertial dynamics of bodies, as determined by local squeeze film effect, prevents diminution of film below certain thickness and reduces the solvation effect. This approach has direct applications for micro-scale mechanisms, where prediction of thin surface adhered film thickness is required for tribological purposes, as well as structural in-service integrity of contacts of vanishing dimensions.

Compression of a Single Transverse Ridge in a Circular Elastohydrodynamic Contact

A detailed experimental study has been made of the behavior of a 100 nm high transversely oriented ridge in an elastohydrodynamic (EHD) contact. Ultra-thin film interferometry has been used to measure film profiles accurately over a very wide range of lubricant film thicknesses, from a few nanometers up to nearly one micron. This enables the recovery of the amplitude of the inlet perturbation geometry with increasing EHD film thickness to be quantified and compared with numerical predictions. In pure rolling under very thin film conditions, corresponding to a smooth surface EHD film thickness of 10 nm, the surfaces near the ridge were squashed down, leading to a constriction in the film of only about 9 percent of the height of the un-deformed ridge. As the EHD film thickness increased, this deformation recovered until the ridge constriction regained about 90 percent of its original height at film thicknesses of about 1 μm. However this relatively rapid recovery only occurred in pure rolling and is attributed to the local perturbation of film convergence which the ridge generates while in the inlet region. This propagates through the contact at the mean speed of the surfaces and—in pure rolling—acts to diminish the effect of local squeeze. When sliding was present, the ridge remained almost fully deformed even when the mean film thickness was as much as twice the height of the original ridge. In this case, the ridge travels through the contact at a different speed from the mean of the two surfaces. The consequent decoupling of the ridge and the convergence perturbation results in a large local pressure due to squeeze which acts to inhibit recovery of the ridge. The general trend of the behavior of the lubricated ridge is shown to be in good agreement with earlier theoretical results.

Analysis of Damping Characteristics of Hydrostatic Air Bearing by using One-Dimensional Bearing Model. 2nd Report. Damping Characteristics of a Grooved Bearing.

To develop a gas bearing with the highest possible damping, we clarify the damping characteristics of a one-dimensional grooved gas bearing model in relation to the squeeze number σ, groove number Ng, depth G and width Lg. The bearing region between two feeding ports is divided by some grooves. From numerical analysis, it is found that Ng, G and Lg have little effect on static stiffness atσ=0. The damping B in the low-σ region decreases when Ng, G and Lg respectively become large. But B in the high-σ region increases with the increase in G and has an extremum value Bopt atσobt which corresponds to the local squeeze numberσ of ten in the divided region. Thus, we can realize a high damping bearing at resonance frequency by decreasing Lg as much as possible, choosing Ng so as to tuneσopt to the corresponding natural frequency and increasing G to the limiting Value which keeps B positive in the low-σ region.

A contribution to the geology of Rusinga Island, Kenya

Summary The paper describes the results of geological mapping and palaeontological collecting in the Gumba peninsula, at the south-western end of Rusinga Island, Lake Victoria, Kenya. A description of the rocks is given, with discussion of the conditions under which they were formed. The sediments seem to represent deposits of shallow, impersistent lakes and flood-plains in a semi-arid region which was subjected to continued volcanicity, often violently explosive. The stratigraphical sequence at Gumba closely resembles that described by R. M. Shackleton at Kiahera in western Rusinga. Structurally the Gumba peninsula conforms to the simple plan established elsewhere in Rusinga. No evidence of violent post-Miocene compressive activity emerges, although minor fractures occur, which may represent local squeeze, dependent on major faulting of normal type. An account is given of early Miocene vertebrates collected at Gumba, and of recent additions to the Rusinga fauna.