Abstract: The ridge structure has ridge elements provided on a top face of a leading edge region directly downstream of a leading edge, which is a laminar flow region of a wing having a swept-back angle relative to a mainstream and provided with a leading edge, and extending in parallel toward downstream of the mainstream. When an angle of a ridgeline connecting vertexes of the ridge elements in an extending direction of the ridge elements relative to x direction is OR, an angle of a flow line of a boundary layer external edge of the mainstream relative to the x direction is ?e, and an angle of a wavefront of stationary cross-flow instability, which is a mode in which a stationary disturbance amplifies inside a boundary layer of the surface and appears as a stationary vortex row, relative to the x direction is ?cf, ?R is between ?e and ?cf.

Abstract: A CPU determines the position of a ball in a virtual game space, and moves a viewpoint based on viewpoint data and the position of the ball. The CPU displays on a monitor TV a portion of a volleyball court in a visible range based on the viewpoint and the direction of an axis thereof. The CPU determines a landing position of the ball, displays a first cursor at the landing position, and displays a player character as it receives the ball when the distance between the player character and the first cursor becomes a predetermined distance before the ball reaches the landing position. When a served ball is received by a player character, the CPU selects a player character to make an attacking action. The CPU assigns a button to the selected player character. When the ball is set by a player character as a setter, the CPU assigns an attack button, and controls the selected player character to perform the attacking action in response to an input signal from the attack button.

Abstract: A CPU determines the position of a ball in a virtual game space, and moves a viewpoint based on viewpoint data and the position of the ball. The CPU displays on a monitor TV a portion of a volleyball court in a visible range based on the viewpoint and the direction of an axis thereof. The CPU determines a landing position of the ball, displays a first cursor at the landing position, and displays a player character as it receives the ball when the distance between the player character and the first cursor becomes a predetermined distance before the ball reaches the landing position. When a served ball is received by a player character, the CPU selects a player character to make an attacking action. The CPU assigns a button to the selected player character. When the ball is set by a player character as a setter, the CPU assigns an attack button, and controls the selected player character to perform the attacking action in response to an input signal from the attack button.

Abstract: A CPU determines the position of a ball in a virtual game space, and moves a viewpoint based on viewpoint data and the position of the ball. The CPU displays on a monitor TV a portion of a volleyball court in a visible range based on the viewpoint and the direction of an axis thereof. The CPU determines a landing position of the ball, displays a first cursor at the landing position, and displays a player character as it receives the ball when the distance between the player character and the first cursor becomes a predetermined distance before the ball reaches the landing position. When a served ball is received by a player character, the CPU selects a player character to make an attacking action. The CPU assigns a button to the selected player character. When the ball is set by a player character as a setter, the CPU assigns an attack button, and controls the selected player character to perform the attacking action in response to an input signal from the attack button.

Abstract: A CPU determines the position of a ball in a virtual game space, and moves a viewpoint based on viewpoint data and the position of the ball. The CPU displays on a monitor TV a portion of a volleyball court in a visible range based on the viewpoint and the direction of an axis thereof. The CPU determines a landing position of the ball, displays a first cursor at the landing position, and displays a player character as it receives the ball when the distance between the player character and the first cursor becomes a predetermined distance before the ball reaches the landing position. When a served ball is received by a player character, the CPU selects a player character to make an attacking action. The CPU assigns a button to the selected player character. When the ball is set by a player character as a setter, the CPU assigns an attack button, and controls the selected player character to perform the attacking action in response to an input signal from the attack button.