bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Proposal for Fuel Specification Activities Relating to General Aviation Intermittent Combustion Engines
Authors: Gonzalez C 
Published: December 2008

It is considered a matter of vital international interest to assure the survival of general aviation and to consolidate its important role in the overall transportation picture around the globe. However, in spite of plentiful supplies of crude, the general aviation industry has suffered severe setbacks in recent years due in part to increased costs and decreasing availability of aviation gasolines. Simply stated, the vulnerability of these fuel supplies is now well substantiated and a concerted effort involving fuel producers, general aviation manufacturers, professional societies such as The American Society for Testing and Materials (ASTM) and The Society of Automotive Engineers (SAE), and user groups is required to establish long-range strategies in this area.
Since 1981, Cessna Aircraft has performed extensive studies and related supportive research activities on current typical general aviation intermittent combustion power plants, and power plants envisioned for development within a time frame of 20 years.
This paper reflects on generalized results of these efforts and the results of a close surveillance of similar related efforts in the United States and abroad. The potential impact of various aviation and currently non-aviation fuels on said future power-plant development activities are covered in detail. Further, the continuing need for assuring acceptable fuel characteristics at the point of aircraft refueling is the key to the safety and success of future activities.
Proposed ASTM activities related to the development of new specifications or revisions or both to existing specifications, considered indispensable to support general aviation fuel requirements envisioned for the future, are defined with justifications for those proposals.
Comparison of the BfU and IAS Binding Adjustment Systems for Competitive Skiers
Authors: Ekeland A , Lund Ø 
Published: December 2008

The binding lateral toe release torques recommended by The Swiss Association for Accident Prevention (BfU) and the International Association for Safety in Skiing (IAS) have been compared for 376 competitive skiers. The ski racers were randomly selected from the participants of seven alpine competitions, arranged in Norway during the winters of 1982 and 1983.
The lateral toe release torques recommended by BfU were generally higher than those recommended by IAS, and for all skiers, the mean difference between the BfU and IAS recommended values was 9%. The difference was highest for adolescents aged 12 to 15 years, being 24% for girls and 15% for boys. In contrast, BfU recommended release torques about 10% below those of IAS for adult males.
The differences between the two binding adjustment systems were less than those previously reported for recreational skiers. This may be related to the better correlation between the body weight and the tibia head diameter, which was observed for the ski racers.
A New Electromechanical Binding/Dynamometer for Actively Controlled Snow Ski Binding Systems
Authors: Wunderly G , Hull ML 
Published: December 2008

This paper describes the design and performance evaluation of a second generation integral binding/dynamometer. To reduce cross-sensitivity, the dynamometer consists of seven elastic elements that are designed to offer minimal mechanical coupling. Through judicious location of the elements and interconnection of strain gages fixed to the elements, the dynamometer signals indicate the generalized loading (that is, six load components) between the boot and ski. Dynamometer elements are contained within the housing of the binding. The housing is fixed to the ski using a technique that makes the dynamometer readings immune to ski flexure. Accuracy checks of the dynamometer under a variety of loadings have documented its ability to consistently resolve forces to within 10% and moments to within 5%.
The binding mechanism can be activated either manually or electrically. Electrical actuation is accomplished by means of a solenoid; manual operation is facilitated by locating manual controls to the front rather than the rear of the boot. To insure that the binding releases when the solenoid is energized, a special mechanism isolates the force, which the solenoid must overcome, from the variable contact forces developed between the boot and binding. By means of laboratory testing under loading typical of release conditions, the reliability of the mechanism to decouple the boot from the ski has been established.
Assumption of Risk—Hockey Injuries
Authors: Abraham CJ , Newman M , Shulman S , Pugh J 
Published: December 2008

Before any recovery for injury can be obtained through litigation, a prerequisite must be attached to the original action in that there must be a duty owed by the defendant to the injured party (plaintiff). If there is any culpable conduct that is attributable to the injured party (or to the decedent), contributory negligence or assumption of risk is taken into account but does not bar recovery.
Although the assumption of risk is a valid defense in an action in which a hockey player is injured, there are many areas that must be investigated relating to the conduct of the injured party. Issues relating to the duties owed to the participants in the sport by the owner of a hockey rink as to possible defective conditions and the participants' right to obtain redress because of defectively designed equipment must be fully investigated and documented prior to placing fault.
There are many risks assumed by a hockey player. Some of the variables relating to the risks depend upon the exercise of reasonable care, the degree of awareness of the common hazards, and the condition of the rink and its surroundings, as well as the type of protective equipment issued and worn by the player.
As a result of the advances in technology over the last decade, there has been a decrease in the number of injuries. However, even with the new proposal for standard practices for ice hockey playing facilities which was drafted this year, the number of injuries reported will probably remain at approximately the same level unless state-of-the-art technology in bio-mechanics and materials science is applied to established guidelines for the protective equipment of the player and the vertical enclosure surrounding the hockey rink.
Clinical Indicators of Dental Implant Performance
Authors: Young FA , Montes GM 
Published: December 2008

The traditional clinical indicators of implant performance are mobility, pocket depth, keratinized tissue width, amount of bleeding, amount of plaque accumulation, and gingival appearance.
This report examines measurements of these variables at intervals of 1 to 2 months for 36 months for 27 implants in 11 rhesus monkeys. The implants were cylindrical porous-rooted titanium alloy and were placed in premolar and molar mandibular sites using a two-stage technique. The implants were used to support both single-unit and multiple-unit restorations. Examination of traditional plots of indicator values versus time revealed no readily observable trends either for individual implants or for pooled implant data. The assumption was made that each observation may be expressed in terms of the additive relationship between the mean response of the total group of responses for an individual, the effect of time, and the error associated with the measurements. The data were analyzed using a multivariate analysis of variance with a repeated measures design (MANOVA, SPSS Inc., Chicago, Illinois). The analysis provided a control on differences between individuals because the effect of time was measured relative to the average response of the individual.
The conclusions of this study are (1) that the technique applied can be useful in determining trends in the measured indicators and (2) that a difference can be observed between implants supporting single-unit restorations and those supporting multiple-unit restorations.
Flexible Porous Titanium for Revision Surgery: Concept and Initial Data
Authors: Ducheyne P , Cuckler JM 
Published: December 2008

Bone stock deficiency is a major challenge encountered in the revision of failed hip arthroplasties. Loosening of the prosthetic components under aseptic conditions results in the loss of trabecular and cortical bone. At revision the surgeon is frequently faced with a thin smooth cortical tube with an almost complete absence of endosteal trabecular bone. Consequently, fixation of the revision component is seriously compromised. The objective of the present paper is to address this issue specifically by discussing a new concept in materials created to alleviate this major problem of deficient bone stock. The authors propose using a porous flexible titanium material to fill void spaces in the deficient bone structure. The material can easily be shaped at the time of surgery and has a pore size in the optimum range for bone ingrowth (100 to 600 µm). In addition, it is possible to infiltrate it with bone cement. Furthermore, the elastic properties of this material closely correspond to those of trabecular bone.
The objective in the design of this new material was to improve the current practice of revision surgery in three problem areas: first, by avoiding brittle fracture due to excess cement thickness; second, by decreasing the risk of disuse atrophy caused by large prosthesis stem sizes; and third, by filling the excess cavity with a material with elastic properties matching those of the missing tissue.
A Method for Quantitative Characterization of Porous Biomaterials Using Automated Image Analysis
Authors: Shors EC , White EW , Edwards RM 
Published: December 2008

An automated image analysis method is described for the quantitative characterization of porous biomaterials. The method consists of impregnating porous materials with epoxy embedding medium and polishing planar sections. Contrast was optimized under a scanning electron microscope using backscattered electron images or under a light microscope using reflected light. The images were analyzed using an image analysis system and software developed for this study. The parameters measured on each image feature of the solid and void fractions, frame by frame, were the area fraction, internal perimeter, minimum crossing distance, number of features per area, equivalent circular diameter, perimeter squared per area, and distribution of equivalent circular diameter squared.
The usefulness of this method was validated by comparing the median values of these parameters and their statistical distributions on Replamineform porous biomaterials derived from echinoid and coral skeletons. We believe that this method for quantitative characterization of the three-dimensional structure of biomaterials is applicable to a broad range of materials and is readily amenable to standardization.
Studies on a Porous Alumina Dental Implant Reinforced with Single-Crystal Alumina: Animal Experiments and Human Clinical Applications
Authors: Yamagami A , Kotera S , Kawahara H 
Published: December 2008

A new type of porous alumina dental implant has been designed. A biological seal is provided by single-crystal alumina on its cervical portion, and fixation capability in bone is provided by a porous alumina layer with an average interconnecting pore size of approximately 130 μm.
The mandibular premolar and molar extraction sites of 15 male rhesus monkeys (3 to 6 years old) were used in the animal experiments. All the implants and superstructures that were not retained by attachment to proximate teeth participated in functional occlusion at all times except during the first two to four weeks.
After four, six, and eight months, histological examinations, including light microscopy (LM), scanning electron microscopy (SEM), and electron probe microanalysis (EPM), were conducted. The surrounding gingival tissue strongly adhered to the single-crystal alumina on the cervical portion of the implant, and prolific bone ingrowth was observed within the porous network of the root component.
The human clinical evaluations showed a high success rate of 94% in 45 cases. Long-term clinical cases were included, the longest implant having survived for eight years in free-standing form. These cases included 23 free-standing cases and 22 bridge cases; 3 of these failed in the first stage of human clinical trials.
Mechanical Properties at Low and High Strain Rates of PE 16 Alloys Irradiated to 9.2 dpa
Authors: Albertini C , Del Grande A , Montagnani M , Pachera A 
Published: December 2008

The mechanical properties of nimonic alloy PE 16 are reported, for the strain-rate range 10−3 to 103 s−1, at ambient temperature, 400 and 500°C, on as-received, thermally aged (9864 h in sodium at 500°C), and irradiated to 9.2 dpa materials. Regarding the irradiated material one observes: (1) the effect of irradiation consisted of a marked increase of flow stress ranging between 100 and 30% and a reduction of ductility of about 20% points with respect to the as-received material; (2) decrease of flow stress with increasing strain-rate of small value at ambient temperature while it reaches the value of about 15% at high temperature; (3) dynamic strain aging with serrations along the flow curves at high temperature and low strain-rate.
The decrease of the flow stress with increasing strain-rate of the irradiated material seems to be caused by (1) the dynamic strain aging that is present at low strain rate and not at high strain rate; (2) the thermal softening caused by the temperature rise during the adiabatic dynamic testing; and (3) the accentuation of the effects of the two preceeding phenomena caused by the damage introduced by irradiation.
Fatigue Crack Growth and Fracture Toughness Properties of Low Fluence Neutron-Irradiated Type 316 and Type 304 Stainless Steels
Authors: De Vries MI 
Published: December 2008

Small compact-tension specimens of Type 316 plate and Type 304 forging have been irradiated in the High Flux Reactor (HFR) at Petten, The Netherlands, up to a fluence level of 2 × 1024 neutrons (n) · m−2 (E &gt; 0.1 MeV) at 573 K. Post-irradiation fatigue crack propagation tests and J-integral fracture toughness tests have been performed at the irradiation temperature. Additional tests were made at the higher temperatures of 723 and 823 K.
The two materials exhibited almost identical crack growth curves after irradiation, despite the chemical and microstructural differences between the materials in the as-fabricated condition.
The irradiation caused a slight increase of the resistance to crack growth under cyclic and monotonic loading at 573 K. This is attributed to irradiation hardening from displacement damage, the latter being observed in the form of the well-known black dots. The additional tests showed modest degradation of the resistance at 723 and 823 K, but the fatigue crack growth resistance decreased significantly under low frequency loading at 823 K because of helium-enhanced intergranular crack formation.
The results are compared with fatigue and toughness curves for Type 304 and Type 316 plate and welds after similar irradiations in the HFR and in thermal material test reactors in the United Kingdom (UKMTR). The closely corresponding curves show the same type of results after the various irradiations.
It is concluded that low fluence (less than 1 dpa, displacements per atom) irradiations at temperatures below 700 K, have a slight beneficial effect on the crack growth resistance of austenitic stainless steels. Nevertheless, the fatigue crack growth rates of Type 316 plate and Type 304 forging are still higher than for weld metal, although the toughness properties are better than for weld metal.
Radiation Effects on the Micromechanics of Fatigue Crack Initiation
Authors: Naughton TD , Ghoniem NM , Lin TH 
Published: December 2008

A micromechanical model is employed to investigate parameters that affect the rate of local plastic strain in and around persistent slip bands in cyclically loaded metals. The model utilizes a solution of the stress field in a semi-infinite elastic-plastic medium under generalized plane deformation. By following the evolution of the stress field, a natural gating mechanism is observed to produce regions of localized deformation. The regions of local deformation develop into extrusions and intrusions that are responsible for the formation of fatigue cracks.
By coupling this micromechanical model with an empirical correlation developed to predict the increase in critical shear stress as a function of fluence and temperature, an investigation of radiation effects on fatigue crack initiation is carried out. It is determined that longer fusion reactor burn times and lower operating temperatures inhibit the crack initiation rate. Because of irradiation induced-hardening, increases in the fatigue limit are predicted for long reactor burn times (&gt;103 s) and low operating temperatures (&lt;300°C). Irradiation is found to increase the number of cycles required to obtain a failure strain at low temperatures and high-cycle fatigue conditions.
A Comparison Between French Surveillance Program Results and Predictions of Irradiation Embrittlement
Authors: Brillaud C , Hedin F , Houssin B 
Published: December 2008

At the beginning of 1986, thirty-two 900-MWe and four 1300-MWe nuclear power stations were in service in France. A regulatory surveillance program is in progress concerning the base metal, weld metal, and heat affected zones of every nuclear pressure vessel; a reference metal sample is also present in each reactor. This surveillance program was implemented largely in accordance with U.S. rules. The specifications for the core shell forgings in MnNiMo low alloy steel and the associated welds require low contents in embrittling elements such as copper and phosphorus. The results presented here concern materials containing less than 0.08 wt% Cu and 0.011 wt% P, except for the welds of the first six reactor vessels, which have 0.13 wt% Cu and 0.019 wt% P maximum. The main aim is to obtain the RTNDT shift from Charpy-V tests, in relation to the fluence measured from fissile and activation dosimeters. Tensile, compact, and three-point bend specimens are also included in the capsules.
Results for the first capsules removed after up to four years of operation, corresponding to fluences (E &gt; 1 MeV) less than 1.5 × 1019 n · cm−2 (2.9 × 10−2 dpa), are presented and evaluated. The mean and upper values of the RTNDT shift are about 20 and 40°C, respectively, and there is no significant difference between parent metal and weld. A new formula to predict embrittlement has been derived from test reactor experiments, because of the strict limits on the residual element contents in French materials when compared with materials for which other formulae have been established. The surveillance program results are discussed and compared with the predictions of these formulae.
Trend Curve Data Development and Testing
Authors: McElroy WN , Gold R , Simons RL , Roberts JH 
Published: December 2008

Existing trend curves do not account for previous and more recently observed test and power reactor flux-level, thermal neutron and γ-ray field-induced effects. Any agreement between measured data and trend curve predictions that does not adequately represent the important neutron environmental and temperature effects as well as the microstructural damage processes, therefore, could be fortuitous. Empirically derived end-of-life (EOL) and life-extension-range (LER) trend curves are presented and discussed in this paper for high temperature [∼288°C (550°F)] irradiation of two weld, two plate, and two forging pressure vessel (PV) steels and low-temperature [∼60°C (140°F)] irradiation of one support structure-type steel.
Preliminary results of a comprehensive study of the effects of environmental variables (neutron spectrum, exposure, exposure rate, and the thermal and γ-ray fluxes associated with surveillance capsules and PV through-wall gradients) were used to develop these trend curves.
Pressurized water reactor (PWR) and boiling water reactor (BWR) plant-specific results together with those of the Poolside Facility (PSF) of the Oak Ridge Research Reactor (ORR) at the Oak Ridge National Laboratory (ORNL) and other research reactor experiments support the existence of a significant material-dependent flux-level effect for PV and support structure steels; that is, a steel may show a decrease, an increase, or no change in the measured Charpy shift with changes in fluxlevel. Further, the actual behavior of a material can change significantly as a function of neutron exposure; also, thermal neutron and γ-ray effects can contribute to observed changes in property, especially near steel-water interface positions with high thermal-to-fast-neutron ratios.
Spectrum Integrated (n,He) Cross Section Comparison and Least Squares Analysis for 6Li and 10B in Benchmark Fields
Authors: Schenter RE , Oliver BM , Farrar H 
Published: December 2008

Spectrum integrated cross sections for 6Li and 10B from five benchmark fast reactor neutron fields are compared with calculated values obtained using the ENDF/B-V Cross Section Files. The benchmark fields include the Coupled Fast Reactivity Measurements Facility (CFRMF) at the Idaho National Engineering Laboratory, the 10% Enriched U-235 Critical Assembly (BIG-10) at Los Alamos National Laboratory, the Sigma Sigma and Fission Cavity fields of the BR-1 reactor at CEN/SCK, and the Intermediate-Energy Standard Neutron Field (ISNF) at the National Bureau of Standards.
Results from least square analyses using the FERRET computer code to obtain adjusted cross section values and their uncertainties are presented. Input to these calculations include the above five benchmark data sets. These analyses indicate a need for revision in the ENDF/B-V files for the 10B cross section for energies above 50 keV.
The Effects of Plasma Processing of Dielectric Layers on Gallium Arsenide Integrated Circuits
Authors: Vanner KC , Cockrill JR , Turner JA 
Published: December 2008

In the commercial production of GaAs I.C.s it is essential to minimise processing induced damage to the shallow semiconducting layers of the MESFET. Currently used fabrication sequences do not involve the use of highly energetic plasma processes such as RIE under conditions which may cause surface damage as a result of ion bombardment. In the development of new fabrication technologies it is essential to ensure that device performance is not degraded by the use of such plasma processes. The use of such techniques as plasma enhanced CVD to deposit passivation or interlayer dielectrics, and subsequent patterning by plasma or reactive ion etching, may adversely affect the active layer as a result of ion or radiation bombardment, or by chemical contamination of the surface.
This paper will present results from a study of the effects of plasma processing of GaAs MESFETs in MMICs. Measurements of device performance show that assessment of FET characteristics can provide a valuable complement to diode measurements and surface analysis.
Economical Pesticide Application: The Reasons for Controlled Droplet Application
Authors: Bals TE 
Published: December 2008

The true costs of pesticide application are still ill-defined and frequently misconceived, despite the fact that they form a large, and growing, proportion of the costs of crop protection. Increased efficiency in the application of pesticides is vital for the achievement of maximum economic yield and is a necessary concomitant of the widespread adoption of Integrated Pest Management programs.
Controlled droplet application (CDA) represents a significant advance in the precision of pesticide application over conventional spraying techniques utilizing hydraulic nozzles. It offers advantages in the logistics of the spraying operation as well as reduced environmental contamination and greater potential operator safety. However, a massive and co-ordinated research effort is required to take full advantage of the potential benefits of CDA and to truly advance crop protection as a science.