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A kinematic model is used to analyze basketball shooting arm motions in the vertical plane that produce desired ball release speed, angle and backspin. The release conditions are related to arm motions using general kinematic equations. The paper compares three types of shooting arm motions: pure hand shots, hand-forearm shots, and general shots controlled by hand, forearm and upper arm motions. In pure hand shots, release speed, angle and backspin are severely limited. All hand-forearm shot configurations are able to produce desired release speed, angle and backspin. General shots redundantly provide shooters with any desired ball release speed, angle and backspin, and they are required to suitably control each joint angular velocity and acceleration.

A basketball shooting arm model is used to estimate arm joint motions for a set of desired release speed, angle and backspin. The model has three rigid planar links with rotational joints imitating an upper arm, forearm and hand with shoulder, elbow and wrist joints. The kinematics of the shooting arm is solved to calculate the joint angles, and the velocity and angular velocity of links at release. There are many angular displacement and velocity combinations of shoulder, elbow and wrist joints to produce the optimal release speed, angle and backspin of the ball at release. Shoulder rotation contributes to the vertical component of release velocity of the ball and elbow and wrist actions mostly produce the horizontal component of release velocity and backspin of the ball when the forearm and hand are nearly vertical at release.

A three dimensional dynamic model is used to estimate the best rebounding position for players in basketball. The model has six distinct sub-models: flight, and ball-contact sub-models of ball-rim, ball-bridge, ball-board, ball-bridge-board, and ball-rim- board contact. It allows both slipping and non-slipping interactions at the ball-contact point. Using probabilistic selection of release velocity, angle, and lateral deviation angle, simulations analyse ball trajectories and good rebounding positions for players. Our estimation includes player wingspan. We analyse the relationship between the most likely player rebound positions and ball rebound positions with high probability. The best player rebound position is usually different from the most likely ball rebound position. Player rebound regions for players with large wingspans are very close to the hoop and include some likely ball rebound positions. For short-range shots, one player is able to collect almost all of rebounding balls but two or three rebounders are required for long-range shots.

Basketball rebound regions are estimated using a dynamic model for short-, medium-, and long-range direct and bank shots and with previously measured standard deviations of release velocity and angle. The model includes basketball stiffness and damping, and contains flight and ball-contact sub-models. The deterministic simulations, together with random Gaussian probability density functions for release velocity, angle and lateral deviation angle, analyze ball trajectories from different shot positions. The results instruct likely rebounding positions. Angled direct and bank shots from the same release position usually have two high-probability rebound positions, one on the same side as and one on the opposite side from the shooter. The highest probability rebound position is typically in or near the optimal shot path plane for capture. Rebound positions from skilled player's shots are usually more predictable.

A three dimensional dynamic model is used to calculate basketball motions for field shots with release conditions: release position, release velocity, backspin angular velocity, release angle, and lateral deviation angle. The model includes basketball stiffness and damping and calculates the slipping and non-slipping, and spinning and non spinning motions at the ball-contact point. The simulations, together with probabilistic selection of release conditions, analyze ball trajectories of field shots and possible rebounding positions for players. The results instruct the best rebounding position for placement of rebounders. We also investigate the effectiveness of denying the optimal shot paths for attempted blocked shots.

A dynamic model is used to analyze the rebounding ball trajectories of free throws. The dynamic model previously described calculates slipping and non-slipping, and spinning and non-spinning motions at the contact point. First ball-contact boundaries for rebounds are estimated in the release velocity and angle space. We show the geometry of ball trajectories for rebounds of free throws with lateral deviation at the release point. The distances and positions for free-throw rebounds are analyzed.

We estimate values of the coefficients of air drag, friction, stiffness and damping for a dynamic model of basketball shots by analyzing ball position and orientation using video data for basketball-rim and basketball-backboard bounce tests. The dynamic model can calculate any configuration change of a basketball during shots. The simulation model is compared to actual bounce tests and the parameters are determined from these experiments. The dynamic model with the identified parameters calculates a ball trajectory similar to the actual measured results. Stiffness and damping coefficients are determined from basketball-backboard bounce tests.

A case of schwannoma extending from the parotid gland to the parapharyngeal space is presented. The patient was a 53-year-old woman. She was referred to us because of a swelling under the left auricle. CT scanning and MRI revealed a tumor extending from the deep lobe of the parotid gland into the parapharyngeal space, compressing the stylomandibular tunnel. This tumor was referred to as a “dumbbell tumor” because of its special shape. Such tumors are rare. The tumor was removed by an extraoral and mandibular swing approach. The histopathological diagnosis was schwannoma with a mixture of Antoni type A and B components. After sugery, no evidence of recurrence has been observed to date.

A newly designed step climbing wheeled robot is discussed with detailed analysis. The proposed mechanism has a compliant element between the front and rear wheels to help the wheels climbing the step which is higher than the wheel radius. The analysis gives the optimal compliance of the compliant element to keep the contact between the wheel and the step wall as long as possible. Some simulation and experimental results are also given to show the effectiveness of the proposed mechanism.

For the passive vibration isolation system, a friction damper is often used becasue it is sipmle, inexpensive and robust. However, the conventional damper of constant friction force has performance limitations ; the isolation characteristic declines when the friction force is large, while the resonant peak becomes large when the friction force is small. Furthermore, the displacement remains apart from the equilibrium position after the vibration diminishs. In order to overcome above drawbacks of the conventional friction damper, a new type of friction damper is proposed in this paper. In the new friction damper, the friction lever mechanism is devised to make the magnitude of the friction force proportional to the relative displacement. This is achieved by connecting the end of the lever to the restoring spring. The transient response and the displacement transmissibility are examined by numerical simulation and experiments, confirming the effectiveness of the linear friction damper.

Osteoma in the maxillary sinus, especially isolated osteoma, is very rare in Japan. We present a case of isolated osteoma in the maxillary sinus that was detected by chance on cephalograms obtained before surgical orthodontic treatment to correct facial asymmetry. There were no signs or symptoms caused by the osteoma. After orthodontic treatment for 3 years, the tumor was removed simultaneously with Le Fort I osteotomy under general anesthesia. The tumor was encapsulated by fibrous tissue and was isolated from the maxillary sinus wall. It measured 28×14×12 mm. Histopathologically, the lesion was diagnosed as an osteoma. There has been no sign of recurrence for 3 years after surgery. Reports of Japanese cases of osteomas of the maxillary sinus are clinicopathologically reviewed.

Recently, tracked vehicles are being equipped with a rubber crawler and they are used for leisure vehicles, snow machines, etc. With these applications, the resonance problems are common knowledge. The vibration characteristics of crawlers are experimentally examined. They have some resonance points caused by the differences in thickness of the crawler. These vibrations will make some noise and possibly cause system destruction. In order to analyze these vibrations, an approximate analytical model, which is based on the linear wave equation, including an effect of crawler velocity is introduced. Vibration characteristics are compared with exact solution and the experimental result. In order to suppress the resonance vibration, a bang-bang control method, which is part of the variable structure system control, is adopted. We experimentally and theoretically examined vibration and control of the crawler. As a result, that control method provides us the possibility of vibration suppression for the actual tracked vehicles.

Anaerobic ammonium oxidation (anammox) and denitrification are two distinct microbial reactions relevant to the global nitrogen cycle. The proposed initial step of the anammox reactions, reduction of nitrite to nitric oxide, has been postulated to be identical to that in denitrification catalyzed by the dissimilatory nitrite reductase of the cytochrome cd1-type. Here, we characterized the copper-containing nitrite reductase homolog encoded by nirK detected in the genome of an anammox bacterium strain KSU-1. We hypothesize that this NirK-type nitrite reductase, rather than a nitrite reductase of the cytochrome cd1-type (NirS), is likely to catalyze nitrite reduction in anammox organism KSU-1.

The purpose of this research was to make a machine or a robot jump over a big obstacle or a ditch. They sometimes need to jump to move over these obstacles. We plan to do fundamental researches on a jumping machine to (1) make the jumping machine jump as high as possible, (2) control the direction of the jumping, (3) control the attitude of the machine in the air, and (4) make it land softly. In this paper the method of making the jumping machine land softly in two dimensional space is described. The optimum soft landing of the jumping machine in two dimensional space is defined. This definition prevents the jumping machine from falling and receiving the big force from the ground. We apply this test to the jumping machine when it jumps and lands in two dimensional space and test the validity of the soft landing by experiment.

The purpose of this research is to make a jumping machine jump over a big obstacle and a ditch. Therefore, the authors plan to do fundamental researches to (1) make jumping machine jump as highly as possible, (2) control the direction of the jumping, (3) control the attitude of it in the air and (4) make it land softly.In this paper the way to make the jumping machine land softly is described. The optimum softlanding of the jumping machine is defined as follows:•First, the impulse which a jumping machine receives from outside is minimized.•Secondly, the maximum of the force which the jumping machine receives from outside is minizized.When the jumping machine lands, we apply this definition to the body and the leg of the jumping machine. Then the validity of the softlanding is proved by the experiments usining the jumping machine.