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This paper aims to explore the effect of automatic transmission fluid (ATF) temperature on the dynamic friction-wear properties of the friction component in a wet multi-disc clutch during the running-in process.

The running-in evolution was explored in terms of global friction performance and instantaneous friction characteristics. The variation of friction torque of the initial 300 engagement cycles was obtained by wet-clutch tests. Finally, an optical microscope was used to detect the wear mechanism of friction surfaces.

The ATF temperature showed a significant effect on the friction-wear performance in the clutch running-in process. The mean coefficient of friction decreased with the increase of the ATF temperature and decreased rapidly in the approximately initial 60 clutch engagements. The higher the ATF temperature was, the thinner the ATF film was, and more asperity summits were cut, thus leading to a smoother surface. Considering the slightly instantaneous friction fluctuation and the wear performance, a proper ATF temperature is necessary.

The results provide theoretical guidance for selecting the optimal ATF temperature during the running-in process.

LUBRICATION of automatic transmissions provides the oil marketers and additive suppliers with a major challenge in terms of fluid development to satisfy the diverse requirements of such units. Fluid development is further complicated by the large number of non‐automotive applications for which automatic transmission fluids (ATFs) are being used.

The purpose of this paper is to deconstruct the problem of data growth as a complex contemporary phenomenon and discuss its implications for the domains of anti‐money laundering (AML) and anti‐terrorist financing (ATF).

The theoretical approach of the paper is based upon an examination of the fundamental ideas around information growth, along with the tradition of systems theory and is based upon many of the theoretical concepts discussed by Niklas Luhmann. The concept of distinction is used throughout the paper to discuss technological consequences.

The volume of data for manipulation and its implications on profiling AML and ATF are discussed while the issue data growth are presented as an elemental and core issue within the paper.

The practical implications of this paper relate to how technology should be appropriated within financial and other institutions and how the decision‐making processes of traditional bureaucracies surrounding AML/ATF should reflect on their utilization of technology.

The originality of this paper lies in its unique dealing of the problem of data growth through its implications and a new theoretical concept is introduced, the concept of electreaucracy to denote the systemic technological interference in bureaucratic conditions and how these influence AML/ATF.

There is agreement in the literature that offenders often acquire guns through unregulated private encounters with friends, family members and petty criminals. Although anecdotes suggest that licensed gun dealers also play a role, most studies have ignored or discounted the possibility that dishonest retailers are a significant source of supply. This effort explores gun markets in Los Angeles by examining the redistributive history of firearms seized by police and by reviewing Federal gun trafficking investigations. One finding, that corrupt licensed dealers diverted sizeable quantities of guns to end users and to unlicensed street vendors, suggests that retail sources may serve as a far more important source of firearms for criminals than is commonly supposed.

There is a significant focus today on the deficiencies of the financial system as the sector continues to boom while facing the growing pains of financial scandals, money laundering and the financing of terrorism around the world. Here, this study aims to investigate past research and the development of knowledge and practice in the area of countering money laundering and terrorist financing. Additionally, we draw attention to the gaps in the preventive mechanisms adopted by countries to fight against anti-money laundering (AML) and anti-terrorism financing (ATF) and to highlight areas for possible future research.

This study was carried out through a systematic literature review of the existing work on AML and ATF.

The general findings of the reviewed papers show the deficiencies in the laws, acts and preventive measures meant to fight money laundering and terrorism financing and support the need for more research in this area in terms of law, regulations and technological matters.

Providing a concrete understanding of the concept of AML and terrorist financing and contributing the theoretical development in the area.

This paper aims to study and compare the friction stability of wet paper-based clutches with regard to the radial grooves (RG) and waffle grooves (WG).

This paper presents an experimental study of a wet clutch concerning the effect of groove patterns on the friction torque and surface temperature. The friction stabilities of RG and WG are investigated with the applied pressure, rotating speed and automatic transmission fluid (ATF) temperature taken into consideration.

The friction torque and surface temperature of WG are larger than those of RG under the same operating condition. The friction torque difference between RG and WG grows with the increase of applied pressure and narrows with the increase of ATF temperature. Additionally, their temperature difference expands via increasing the rotating speed and ATF temperature or reducing the applied pressure; in this way, not only the variable coefficient difference between RG and WG can be narrowed, but also the friction stability of the clutch can be improved dramatically.

This paper explains the thermodynamic differences between RG and WG; moreover, it is verified experimentally that WG has a better friction stability than RG.

The single recent event that has most significantly changed the way in which automotive transmission fluids are defined took place in 1990 when General Motors published its Dexron HE specification. This represented the first major modification of General Motors' Automatic Transmission Fluid (ATF) specifications since July 1978. (The original Dexron II specification was first published in 1973.) The driving force behind the timing for the introduction of this specification was the launch, in 1991, of the Buick Park Avenue with a newly redesigned, electronically‐controlled version of the older Hydramatic 440‐T4 Front‐Wheel‐Drive (FWD) automatic transaxle. This unit was designated the 4T‐60E. The majority of designers of computer‐controlled transmissions use electro‐hydraulic solenoid valves to open and close hydraulic circuits to make the transmission shift. For this reason, many of the new transmission designs require ATFs to have superior low‐temperature fluidity properties. Dexron IIE calls for fluids having a −40°C Brookfield viscosity of less than 20,000 cP, compared with the 50,000 cP requirement of the Dexron II. Only fluids approved to the new specification will be officially endorsed by GM from January 1993.

The purpose of this paper is to reduce the drag loss and study the effects of operating conditions and groove parameters such as flow rate and temperature of automatic transmission fluid, clearance between plates, groove depth and groove ratio on the drag torque of a wet clutch for vehicles, parametric analysis of the drag torque model of wet multi-plate friction clutch with groove consideration.

Both experimental and numerical research was carried out in this work. Parametric groove models, full film lubrication flow model and pressure distribution model are established to investigate the effects of the grooves on drag torque of a wet clutch. Multigrid method is used to simplify the solution.

In this paper, a drag torque model of a wet multi-plate friction clutch based on the basic theory of viscous fluid dynamics is examined through experimental and numerical methods that take grooves into account, and the change trend of drag torque with operating conditions and groove parameters is analyzed.

Multigrid method is used to solve the governing equations, which simplifies the solution process because of the restrictions and interpolation operations between the adjacent layers of coarser and fine grids. These works provide insight into the effect regularity of operating conditions and groove parameters on drag torque of a wet multi-plate friction clutch. Furthermore, variable test conditions and sufficient experimental data are the main functions in the experimental research.