Bicycle Type Research Articles

Off-Road Cycling Injuries

Off-road bicycles, commonly called 'mountain bikes', have become increasingly popular worldwide since their introduction in the western US in the late 1970s. This popularity is partly because these vehicles can be ridden on a wide variety of terrain which is not accessible to other types of bicycle. Although early versions were rather crude, off-road bicycles today typically include high strength, lightweight frames with a wide array of available suspension and braking systems. Virtually all aspects of the technology continue to evolve, including components and protective equipment. As the popularity of off-road cycling has increased, so too has the interest and level of participation in the competitive aspects of the sport. Currently, 2 organisations--the National Off-Road Bicycle Association (NORBA) and the Union Cycliste Internationale (UCI)--sponsor the major events within the US and around the world. To date, the majority of studies have been descriptive in nature, with data collected via self-report, questionnaire formats. Only 1 prospective study has been reported thus far, which surveyed a major international competition held in the US in 1994. Injury rates calculated on the basis of injuries per ride or event in competitive venues have been reported, ranging from 0.2 to 0.39% compared with 0.30% for recreational participants. Retrospective data collected from recreational and competitive riders indicate that from 20 to 88% of those surveyed reported having sustained an injury during the previous year of participation. The majority of injuries appear to be acute, traumatic episodes involving the extremities, with contusions and abrasions being the most common. In general, the incidence of more severe injuries such as dislocations, fractures and concussions is low. Comparisons between road and off-road cycling events indicate that off-road cyclists sustain more fractures, dislocations and concussions than their road-event counterparts. Future research should incorporate epidemiological methods of data collection to determine the relationships between vehicle design, terrain and safety equipment and riding-related accidents. Further, those engaged in such research should attempt to set a standard definition for injury.

New Pathways in Tellurium‐Chalkogen‐Nitrogen Chemistry: Preparations, Structures, and Properties of Telluraheterocycles

AbstractTreatment of Se(NSO)2 with TeF4 in CH2Cl2 yields the compounds (4a) and (5b), while with TeBr4 after six months (2d) is formed. An almost quantitative yield of Cl4Te2N4S2 (6) is obtained from either Cl6Te2N2S (1a) and (CH3)3SiNSNSi(CH3)3 in CH2Cl2 at 20°C (2 d) or TeCl4 and (CH3)3SiNSO (molar ratio 1:2) in CH2Cl2 at 60°C (3 d). The use of (CH3)3SiOSi(CH3)3 as solvent in the last mentioned procedure gives 1a and small amounts of Cl2Te(NSO)2. Similarly, F2Te(NSO)2 is prepared from TeF4 and (CH3)3SiNSO in CH2Cl2. Dechlorination of 1a with (C6H5)3Sb leads to (2a), which is also produced from TeCl4 and [(CH3)3Si]2NSN[Si(CH3)3]2. When TeF4 is used instead of TeCl4 (molar ratio 3:1) the salt (7a) is formed. Similarly, (7b) is prepared from 2a and AsF5 or Ag+[AsF−6] in SO2. A new method for the preparation of bicyclic type 1 telluraheterocycles involves bromination of 2a yielding Cl2Br4Te2N2S (1b). Dehalogenation with (C6H5)3Sb converts 1b into (2b). When 2b is treated with Br2 in CH2Cl2 an oxidative halogenation takes place with formation of Br6Te2N2S (1c). Metathetical exchange between 2b and Ag+[AsF−6] gives (7c). Isostructural S(NSO)2 reacts with TeCl4 for several weeks at 60°C in CH2Cl2 to form S4N4. TeCl4 and [S5N+5][Te3Cl−3], in contrast to the corresponding reaction with Se(NSO)2. The molecular structures of 4a, 7b, 8, and [S5N+5][Te3Cl−13] have been determined by X‐ray diffraction methods. Spectroscopic data for all new compounds are presented.

The characteristics and use patterns of bicycle riders in the United States

While there are large numbers of injuries and deaths involving bicycles every year, little information about the characteristics and use patterns of the general population of bicycle riders has been available. This article describes the results of a comprehensive national survey of U.S. bicycle riders conducted in 1991. The survey was based on the Mitofsky-Waksberg method of random-digit-dialing, a two-stage sampling procedure designed to give all telephone numbers an equal chance of selection. The survey collected information on a representative sample of 1,254 U.S. bicycle riders. The results of the survey provide detailed information on: the number of riders and bicycles in use; the demographic characteristics of rider households; rider characteristics (e.g., age, gender); bicycle use patterns (e.g., where and how much bicycles are used); helmet use patterns; and the types of bicycles in use. Some research implications of the survey results are also discussed.

Evaluation of Microbial Insecticides for Control of Armyworms on Winter Wheat, 1993

Abstract Treatments were applied on 19 May to winter wheat drilled on 6 inch row spacings at soft dough stage, in Mississippi Co., AR. A bicycle type CO2 sprayer with a 12 ft boom equipped with TX-4 hollowcone nozzles on a 20-inch spacing was calibrated to deliver 10.5 gpa at 40 psi. Plots were 12 × 50 ft separated by 6 ft borders arranged in a RCBD with 4 replications. A spreader sticker (CS-7) was added (1 ml per gal). The application was made in the late afternoon. No rainfall occurred during the test. Five Bacillus thuringiensis products and 3 viruses (Anagrapha falcifera NPV [AfNPV], Pseudaletia unipuncta NPV [AwNPV] and P. unipuncta GV [AwGV]) were tested. Larval counts were made from the perimeter of the plots prior to the application, and again 4 DAT within plots. Armyworms in two 6 ft samples per plot were counted by searching the soil surface, debris, and base of plants. Just prior to the search, plants were jostled to knock larvae on plants to the ground. Larvae were collected from control and virus treated plots and individually placed in 1 oz plastic cups half-filled with pinto bean diet. Larvae were held until death of adult emergence. Yields were not taken.

Motion Control of the Parallel Bicycle Type Mobile Robot which is Composed of a Triple Inverted Pendulum (lst Report, Stability Control of Standing Upright, Ascending and Descending of Stairs)

In the previous papers, we reported the motion control methods and experimental results on the parallel bicycle which is composed of a double inverted pendulum type body pivoted on the axis of parallel wheels and a pair of controlling arms suspended from the upper end of the body. The inverted pendulum type parallel bicycle can stabilize itself skillfully and move according to the servo reference by means of its controlling arms or the wheels. However, it cannot negotiate uneven paths such as stairs. For travels on uneven paths, we have developed a new type of parallel bicycle with an articulated joint connecting two divided body sections. This bicycle can change its configuration by folding its body, and can adapt itself to different environments or applications. Some control methods for the new vehicle and experimental results are described in detail in this paper.

Motion Control of the Parallel Bicycle-Type Mobile Robot which is Composed of a Triple Inverted Pendulum. (1st Report, Stability Control of Standing Upright, Ascending and Descending of Stairs).

In the previous papers, we reported the motion control methods and experimental results on the parallel bicycle which is composed of the double inverted pendulum-type body pivoted on the axis of the parallel wheels and the double controlling arm suspended from the upper end of the body. The inverted pendulum-type parallel bicycle can be well stabilized and travels according to the servo reference by using the controlling arms or the wheels. However, it cannot be adapted to uneven paths such as stairs. In order to travel uneven paths, we have developed the new type of the parallel bicycle with an articulated joint which connects the bodies divided in two pieces. The bicycle can change its configuration by folding its body and adapt itself to environment or application. The control methods and experimental results on the new vehicle are described in detail in this paper.

Postural and Driving Control of the Variable-Configuration-Type Parallel Bicycle. 2nd Report, Standing up and Falling down Control by Torque Control Method.

We developed a new type of parallel bicycle with a working arm and a controlling arm. By using these arms, the robot can vary its configuration and change locomotion mode according to the working conditions or environments. In the previous paper, several kinds of configuration and locomotion mode were realized by using gain-changing control method. In this paper, torque control method was proposed and applied to the standing up motion and braking of falling down of the robot. The experiments shows that the torque control method is better than the gain changing one because of the smooth and high speed motion without any critical vibration. Furthermore, we succeeded in soft landing of the falling down motion of the robot by using self-learning control method applied to provide the input torque. According to the experimental results, this type of the robot can be expected to play active roles in service or maintenance use.

Postural and driving control of the variable-configuration-type parallel bicycle.

The authors have developed a new type of parallel bicycle which can vary its configuration and change locomotion mode according to the working conditions or circumstances. The fundamental components of the vehicle are an inverted-pendulum-type parallel bicycle, a working arm and a controlling arm. By combining the components, three kinds of the configurations can be realized : a parallel bicycle with a working arm and an L-shaped controlling arm, a double-steered wheeler with a controlling arm, and a four-wheeled vehicle with a working arm. This paper describes the control methods of motions obtained with the first-type parallel bicycle with a working arm and an L-shaped controlling arm, and experimental results. The postural and driving control using the controlling arm is very useful and the motion of the working arm is well controlled by it. When an auxiliary wheel is installed at the tip of the working arm and the arm is lowered until it touches the ground, the vehicle is converted into a tri-wheeled car. Conversion from the two-wheeler to the tri-wheeler and the inverse conversion are also successfully attained by the intelligent control method proposed here.

Women and American Socialism, 1870-1920

Looks at different types of bicycles, gives tips on riding in city traffic, and shows how to avoid the most common cycling accidents.