Stock market efficiency withstands another challenge : solving the “sell in May/buy after Halloween” puzzle

Examining the years 1970 to 1998, Bouman and Jacobsen (2002) document unusually high monthly returns during the November-April periods for both United States (U.S.) and foreign stock markets and label this phenomenon the Halloween effect. Their research suggests that the Halloween effect represents an exploitable anomaly and has negative implications for claims of stock market efficiency.

Re-examining Bouman and Jacobsen’s empirical results for the U.S. reveals that their results are driven by two outliers, the “Crash” of October 1987 and the collapse of the hedge fund Long-Term Capital Management in August 1998. After inserting a dummy variable to account for the impact of the two identified outliers, the Halloween effect becomes statistically insignificant. This anomaly is not economically exploitable for U.S. equity markets. We extend the research to the S&P 500 futures contract and find no evidence of an exploitable Halloween effect over the period April 1982-April 2003.

FEA comparison of high and low pressure tube hydroforming of TRIP steel

The increasing application of hydroforming for the production of automotive lightweight components is mainly due to the attainable advantages regarding part properties and improving technology of the forming equipment. However, the high pressure requirements during hydroforming decreases the costs benefit and make the part expensive. Another requirement of automotive industries is weight reduction and better crash performance. Thereby steel industries developed advanced high strength steels which have high strength, good formability and better crash performance. Even though the thickness of the sheet to form the component is reduced, the pressure requirement to form the part during expansion is still high during high pressure hydroforming. This paper details the comparison between high and low pressure tube hydroforming for the square cross-section geometry. It is determined that the internal pressure and die closing force required for low pressure tube hydroforming process is much less than that of high pressure tube hydroforming process. The stress and thickness distribution of the part during tube crushing were critically analysed. Further, the stress distribution and forming mode were studied in this paper. Also friction effect on both processes was discussed.

Processing and characterization of porous aluminum

Aluminum foams are now being introduced into automotive industry to reduce weight, to absorb energy in crash situations and to carry sound or heat absorbing functions. In the present study, a novel Spark Plasma Sintering (SPS) process for producing porous aluminums with controlled pore size and porosity and superior energy absorption has been developed. Experimental procedures included the mixing of starting powders, compacting, SPS sintering and leaching out of the space-holding particles. Porous aluminums with various porosities and a wide range of pore size distributions can be produced by the SPS process. Optical microscopy, scanning electron microscopy (SEM) and quantitative image analyses were used to characterize the porous aluminums. Compressive tests were carried out on the aluminum foams to evaluate the mechanical properties.

Strain rate effects on the energy absorption of rapidly manufactured composite tubes

Quasi-static and intermediate rate axial crush tests were conducted on tubular specimens of Carbon/Epoxy (Toray T700/G83C) and Glass/Polypropylene (Twintex). The quasi-static tests were conducted at 10 mm/min (1.67 x 10¯⁴ m/s); five different crush initiators were used. Tests at intermediate rates were performed at speeds of 0.25, 0.5, 0.75, 1, 2, and 4m/s. Modes of failure and specific energy absorption (SEA) values were studied. The highest SEA measured was 86 kJ/kg. This value was observed using Carbon/Epoxy samples at quasi static rates with a 45° chamfer initiator. The highest energy absorption for Twintex tubes was observed to be 57.56 kJ/kg during 45° chamfer initiated tests at 0.25 m/s. Compared with steel and aluminium, SEA values of 15 and 30 kJ/kg, respectively, the benefits of using composite materials in crash structures become apparent.

Vehicle design for minimum societal harm

A design technique was developed to provide the best protection to all occupants in the real-world crashes that occur on Australian roads. A team of experts from around the world was marshalled to analyse crash data, develop new information on impact injury and a new computer optimising technique for simulation of side impact crashes.

Processing of fine-grained aluminum foam by spark plasma sintering

Porous materials are now becoming attractive to researchers interested in both scientific and industrial applications due to their unique combinations of physical, mechanical, thermal, electrical and acoustic properties in conjunction with excellent energy absorption characteristics. Metallic foams allow efficient conversion of impact energy into deformation work, which has led to increasing applications in energy absorption devices. In particular, foams made of aluminum and its alloys are of special interest because they can be used as lightweight panels, for energy absorption in crash situations and sound or heat absorbing functions in the automotive industry with the aim to reduce weight to improve crashworthiness, safety and comfort.

Cultural connections across time and place : Wardell's late 19th century Genazzano FCJ College Kew

The Catholic Church was profoundly affected by the 1872 Victorian Education Act, which made education secular, compulsory and free, and led to the withdrawal of state aid to religious schools. In order for the Church to run its own schools, it had to look overseas for help and invited religious teaching orders, such as the Faithful Companions of Jesus (FCJs) to set up schools in Victoria, Australia. In many instances purpose built buildings were designed by architects. William Wardell was well established in private practice in Sydney when he designed the new Convent and School, Kew, Victoria, for the FCJ Sisters, in the late 1880s. Building commenced just before the crash of Marvellous Melbourne. Less than half of the total concept of Wardell’s original plan was built. It opened for business in April 1891. Today this building forms the heart of the contemporary Genazzano FCJ College Kew. Many histories intersect in this commission. The vision for Catholic education in Victoria in the late 19th century is critical. The FCJs charism and their experience of teaching in Europe, in France, England, Ireland, Italy and Switzerland, provides a model for their work in Australia. At this time the importance of architecture to society is made manifest in education and its demands on building: if learning is valued then buildings should reflect this, for public buildings can shape morality. Wardell was trained as a Gothic Revival architect and his building participates in a broader medieval and Gothic tradition. Wardell’s original plan for this late Victorian Gothic style asymmetrical three-storeyed building, was designed to integrate a convent, school, chapel, and dormitories. This paper considers architectural history from diverse perspectives, educational, social, religious, economic and political, recognising the complexity of this project and the people who played a part in its conception and realisation.

An investigation of complex shapes during low pressure tube hydroforming

Hollow structures made of Advanced High Strength Steel (AHSS) are increasingly used in the automobile industry for crash and structural components. Generally high pressure hydroforming is used to form these tabular parts, which is a costly manufacturing process due to the high pressure equipment and large tonnage presses required. A new process termed low pressure hydroforming, where a pressurized tube is crushed between two dies, represents a more cost effective alternative due to the lower pressures and die closing forces required.

In this study the low pressure tube hydroforming of one simple and two different complex hollow shapes is investigated. The complexities of the pat1S compared to simple shapes are critically studied and the die filling conditions are investigated and discussed. FUl1hennore the thickness distributions over the circumference of the part during forming are analyzed.

Formability and forming of advanced steels

The thesis identified how advanced high strength steels perform compared to conventional steels in terms of weight reduction and crash performance for automotive bodies. The novel production method of low pressure tube hydroforming was applied to form these advanced steels to reduce the press tonnage and fluid pressure compared to the conventional high pressure process. In addition analytical models were developed to predict the force and pressure in the low pressure process.

High strain rate tensile properties of rapidly cured woven carbon fibre composites

Tensile tests at high speeds corresponding to automotive crash events were conducted to understand the dynamic properties of rapidly cured woven carbon fiber composites. The High Strain Rate (HSR) experiments were conducted on a servo-hydraulic machine at constant velocities up to a maximum of 25 m/s (82 ft/s). Results from HSR tests were compared with the static results to determine the rate sensitivity of the composite. A high speed camera was used to capture the failure at HSR. The tensile properties of rapidly cured laminate were compared to oven cured laminate to justify its productivity while maintaining the desired properties. The methodology used to achieve constant velocity during HSR tests is discussed in detail. The specimen geometry was specially designed to suit the test rig and to achieve high speeds during tests. All the specimens failed with linear elasticity until sudden brittle fracture. The Scanning Electron Microscopy (SEM) images of the fracture zone were used to identify the failure modes observed at static and high strain rates.

Modelling the side impact of carbon fiber tubes

Metallic tubes have been extensively studied for their crashworthiness as they closely resemble automotive crash rails. Recently, the demand to improve fuel economy and reduce vehicle emissions has led automobile manufacturers to explore the crash properties of light weight materials such as fibre reinforced polymer composites, metallic foams and sandwich structures in order to use them as crash barriers. This paper discusses the response of carbon fibre reinforced polymer (CFRP) tubes and their failure mechanisms during side impact. The energy absorption of CFRP tubes is compared to similar Aluminium tubes. The response of the CFRP tubes during impact was modelled using Abaqus finite element software with a composite fabric material model. The material inputs were given based on standard tension and compression test results and the in-plane damage was defined based on cyclic shear tests. The failure modes and energy absorption observed during the tests were well represented by the finite element model.

The indentation behaviour of carbon fibre composite tubes-experiments & modelling

Metallic tubes have been extensively studied for their crashworthiness as they closely resemble automotive crash rails. Recently, the demand to produce lighter weight, yet safer vehicles has led to the need to understand the crash behaviour of novel materials, such as fibre reinforced polymer composites, metallic foams and sandwich structures. This paper discusses the static indentation response of Carbon Fibre Reinforced Polymer (CFRP) tubes. The side impact on a CFRP tube involves various failure mechanisms. This paper highlights these mechanisms and compares the energy absorption of CFRP tubes with similar Aluminium tubes. The response of the CFRP tubes during bending was modelled using ABAQUS finite element software with a composite fabric material model. The material inputs were given based on standard tension and compression test results and the in-plane damage was defined based on cyclic shear tests. The failure modes and energy absorption observed during the tests were well represented by the finite element model.

Dynamically opted protection envelope (DOPE) - A cost-effective strategy of insuring an investment portfolio

Popular ways of hedging downside risk of a stock portfolio is by means of a constant proportion portfolio insurance (CPPI) strategy or by means of an options-based portfolio insurance strategy (OBPI). However both have drawbacks in terms of practical applicability given transaction costs. Moreover they are not useful in times of very low liquidity e.g. in a market crash. Here we shall first review the common portfolio insurance techniques and then posit an alternative approach using a zero-coupon bond to extract downside coverage to the extent desired by an investor. While the posited strategy will not guarantee full downside protection for the entire investment horizon, it is unaffected by transaction costs resulting from need to periodically reallocate funds and is a lot easier to implement practically compared to options-based strategies. Unlike CPPI and OBPI, it will work in a crash situation too.

Car skids and crashes in street SFX

A sound effect of a car skidding and crashing in the street - a long street ambiance is included for your own after-effects.