Abstract: Abrasion resistance is further enhanced in a sliding member used in an internal combustion engine. With respect to a valve lifter 6 used in an internal combustion engine 100, hard particles having higher hardness than the valve lifter 6 are dispersed onto the top face 61 of the valve lifter 6, and a nitriding treatment is conducted on the top face 61 dispersed with the hard particles.

Abstract: It is a technical common knowledge that a chaplet used in casting of a hollow casting is fusion-bonded with the melt and is incorporated into the casting. However, the adhesion between the chaplet and the casting body is not necessarily satisfactory, thereby incurring the strength reduction of a thin-wall hollow casting. A core for a thin-wall hollow casting according to the present invention is provided with a chaplet mounted thereon. The chaplet has arcuate portion 2 with a gap 5 and a plurality of projections 4 from an outer peripheral of the arcuate portion and is in contact with an inner wall 7 of a mold. The entire arcuate portion of the chaplet is included in a groove 6 formed around an outer peripheral portion of the core body. Only the projections 4 of the chaplet protrude from the core body, when the chaplet is inserted in the groove.

Abstract: A semiconductor device having a well region of a first conduction type formed in a main surface of a semiconductor substrate, and a nonvolatile memory element formed at the well region is provided. The nonvolatile memory element comprises a gate electrode formed over the well region through an insulating film for charge storage, and a source region and drain region of a second conduction type which are separated from each other and are disposed in the well region. The well region includes a third semiconductor region, a second semiconductor region which is arranged at a position deeper than the third semiconductor region, and a first semiconductor region that is arranged at a position deeper than the second semiconductor region. The first and third semiconductor regions, respectively, have an impurity concentration higher than the second semiconductor region.

Abstract: A threaded fastener lighter in weight and easier to produce is made by the moderate temperature-forging, from a raw magnesium material that contains microcrystals whose diameter is about 100 &mgr;m or less. The raw material may be pure magnesium of industrial grade in one case, and alternatively be any magnesium alloy or such a composition as comprising as its matrix the alloy or pure magnesium, in the other cases. The raw material has a superplastic property and a fine-granulated metallographic internal texture, and when making the fastener, will be heated to 250-400° C. at which superplasticity takes place to facilitate the forging to form the fastener. A method proposed in the invention to make the fastener is thus such that the number of necessary processing steps is reduced and manufacture cost is lowered.

Abstract: A ROM is provided, storing a game space having a plurality of places, a main character belonging to a sport team, and a plurality of other characters provided with different capabilities regarding the sport. A wandering processing means causes the main character displayed on a monitor to move to desired places in the game space according to operation of operating keys, executing conversation processing regarding the above solicitation between the displayed main character and other characters, and in the event that the result of the conversation is success in solicitation, the other character is registered to the member registering means. Thus, a game with a high gaming nature and absorbing interest can be provided, wherein the relation between the character of the player and a specific character can be influenced via a main character, and this influence can be reflected on the game story.

Abstract: A main rocker arm which is pivotally mounted on a rocker shaft has one or more sub-rocker arms pivotally mounted thereon. The main rocker arm is arranged to synchronously open and close two poppet valves. Each of the sub-rocker arms can be selectively locked to the main one by way of hydraulically operated plunger arrangements. The main rocker arm is provided with a roller type cam follower which follows a low speed cam. The sub-rocker arms are provided with followers which engage high or very high speed cams. Lost motion springs which maintain the sub-rocker arms in contact with the cams are mounted on the main rocker arm.