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A 69-year-old female was admitted to our hospital due to general malaise and appetite loss. On physical examination, a tumor was palpable in the upper left abdomen. A complete blood count revealed anemia. An abdominal computed tomography suggested ileus secondary to transverse colon cancer. Transverse colectomy with D3 lymph node dissection was performed. The final diagnosis was moderately differentiated tubular adenocarcinoma, StageⅡ, T4aN0M0. The tumor marker level was re-elevated at 9 months after surgery; computed tomography and lower gastrointestinal endoscopy indicated local recurrence. The patient underwent a second laparotomy; however, it became an exploratory surgery due to aggressive local invasion. FOLFOX therapy was initiated from postoperative day 55 for tumor control. Tumor markers decreased markedly after 5 courses of therapy, and a complete response was achieved at 6 months after the second surgery. Subsequently, 29 courses of FOLFOX therapy were administered for 2 years and 1 month. At this time, the patient discontinued chemotherapy at her desire. No signs of recurrence have been observed at 6 years after withdrawal.

A new rotatable test rig is developed to perform oil churning loss experiments to clarify the influence of the relative position of gears and casing wall shape of gear box under splash lubrication condition. Torque losses are measured and photos are taken using a stroboscope to observe the oil behavior. Based on the test results, it has been confirmed that in addition to the well-known factors, relative position and casing wall shape have significant effects on the churning loss and should be considered in the modeling process, which has been neglected in most previous studies. In this article, the importance of the steady-state oil surface profile (SOSP) is emphasized. New ideas are proposed on how other working conditions such as immersion depth and rotation speed influence the churning loss.

Background: There have been many reports that caries susceptibility of children with Down syndrome is lower than that of unaffected children. However, the perspectives on the factor of caries susceptibility have not yet been unified due to its diversity. This study aimed at comparing children with Down syndrome with unaffected children regarding the biochemical analysis and the histological observations with increasing depths from the surface of deciduous teeth. Methods: Atomic concentrations of calcium and phosphorus at the core regions of the enamel prism were analyzed using an electron probe microanalyzer. Histological observations were simultaneously conducted. In addition to the subjective comparisons, percentages of the enamel prism cores (interprismatic substance area ratio) were also calculated. Results: Regarding calcium and phosphorus concentrations or calcium/phosphorus ratio, there were no significant differences between the two groups at any of the layers. Additionally, there was no significant change in either group with increasing depths from surface. The findings of enamel surface revealed three-dimensionality in unaffected children, while smoothness in children with Down syndrome. In children with Down syndrome, the outline of enamel prisms showed some of which formed incompletely. Enamel prism cores were similar to the interprismatic substance in terms of crystal structure. Interprismatic substance area ratio of children with Down syndrome was lower than that of unaffected children in all the layers except at 150 μm and 250 μm. Conclusion: In this study, the deciduous canine enamel of children with Down syndrome was thought to include more organic material than that of unaffected children.

The novel use of SiCN underneath TEOS oxide as a bonding surface in the wafer bonding of Backside-illuminated (BSI) sensor is proposed and the mechanism of void control by SiCN is clarified. In general, high-temperature processing results in generating voids between the wafer interfaces after bonding due to the release of high-pressure H 2 O contained in TEOS. In the proposed mechanism, the SiCN exposed to high-temperature H 2 O is oxidized thereby preventing the emission of high-pressure H 2 O gas. This paper analyzes the role of SiCN in this mechanism.

Background Systemic disturbance during the fetal and postnatal periods in disabled children may affect the formation and mineralization of deciduous tooth enamel. Aim To reveal differences in the status of mineralization in the surface and inner layers of deciduous tooth enamel between children with cerebral palsy (CP), those with Down syndrome (DS), and controls. Methods Using extracted deciduous teeth obtained from CP children (5 teeth), DS children (5 teeth), and control children (11 teeth), fluoride and magnesium concentrations, used as mineralization parameters, were measured in three regions of the enamel at different depths: the enamel surface (ES), neonatal line (NL), and dentino-enamel junction (DEJ). Results Fluoride concentration was significantly higher in the ES region than in the NL or DEJ region in all three groups. There was no significant correlation between type of disability and fluoride concentration. Magnesium concentration was significantly higher in the DEJ region than in the NL or ES region. A significant correlation was seen between type of disability and magnesium concentration. Conclusions Magnesium concentration was significantly higher in DS children than in control children, suggesting that DS children undergo poorer mineralization. Magnesium concentration tended to be higher in CP children than in control children.

For the purpose of improving the efficiency of automotive transmission, there is a greater need to modify even the gear dimensions and tooth surface for reducing gear mesh power loss. In our study, we developed the prediction program and examined some reduction methods of the mesh power loss. To predict the mesh power loss of transmission gears accurately, it is necessary to estimate the friction coefficient at tooth meshing surface. But there was no formula with high accuracy for useful estimation of friction coefficient under mixed lubrication condition such as gear meshing condition. The one of authors proposed the new estimation formula of friction coefficient. In this paper, the usefulness of proposed estimation formula is confirmed and the prediction program of mesh power loss applying the proposed estimation formula of friction coefficient is also validated by several gear pair tests. From this prediction program and some experiments, the influence of gear dimensions, tooth surface modification, tooth surface roughness and driving condition on mesh power loss is discussed.

A clear yield point was not seen in the tensile strength of the aluminum sintering body. As for the molding pressure, 170MPa was the upper limit value. Hardness, the radial crushing strength increased, but the oil content. As for the sintering temperature, 545°C were the upper limit values. Hardness, the radial crushing strength increased, but the oil content increased to 545°C, too. The friction examination of molding pressure 170MPa showed limit PV value 6.46MPa.m/s. The friction examination of sintering temperature 545°C showed aspect pressure 17MPa. The life examination maintained friction temperature to approximately 40°C until 30hours.

The tests for sliding characteristic of sintered aluminum with retained oil for sliding bearing were conducted . The sintered aluminum materials blended of silicon with 40wt% weight in maximum were made for experiments. Results obtained are as follows. There was the relation among the oil content, the radial crushing strength and the hardness. There was the limitation of mean grain size and weight fraction of silicon for the higher quantity of oil and the higher mechanical properties. In that condition, the hardness increased with the quantity of retained oil in subsurface of tested rings.

Machine designers are sometimes confronted with high contact pressure conditions which generate plastic deformation. However there is no clear design method for such severe condition. We investigate the contact condition in the high contact pressure by using a ball-on-glass disc type test. According to the test results, the following conclusions were obtained. 1) The ratio of calculating contact pressure and the hardness in consideration of working hardness, the number of the ratio is settled about 0.4 for any loading condition. 2) In the condition of high contact pressure generating plastic deformation, the contact pressure converges with constant value according to the work hardening behavior of material.

Micro traction drive is a transmission by using of modified ball bearing. The traction force is generated by the thrust pre-load between inner race and outer race. The driving force is transmitted by using of retainer that is connected to output shaft. Test-drives of micro traction drive have been carried out as single stage type (reduction ratio around 2.0) and as tandem stage type (reduction ratio 7.3). The dimension of the micro traction drive is 10mm inner diameter, and 30mm outer diameter. As a result of the test, we have found that single stage type traction drive can transmit higher torque, higher number of revolution with lower noise and vibration than planetary gear head. Tandem type traction drive has been successfully operated at maximum speed 20000 rpm.

This paper discusses about the new vibration model of gear pair in consideration of oil film force in order to evaluate the dynamic load in steady meshing and the impact load in tooth flank separation with sufficient accuracy. This new vibration model is constituted by combining an oil film model and a spring and damping model in series. In the oil film model, the force produced according to the wedge and the squeeze effect of an oil film between meshing teeth was modeled. Moreover, it was also taken into consideration that viscosity changes with oil film pressure. A spring and damping model represent the force generated by bending of a tooth, and fluctuation of stiffness accompanying change of number of meshing teeth and meshing position was taken into consideration. This model was applied to a pair of gears on which fixed torque acts and the camshaft drive gear which tooth flank separation generates by fluctuation torque. And comparison of a calculation result and an experimental result was performed to tooth root stress. The calculation results and the experimental results showed the good coincidence, and it was clarified that the model was appropriate.

Traction drive makes oil film between two rollers, and power is transmitted by oil film shearing. It has the following characteristics. (1) Traction drive can be operated at low level of vibration and noise, so they are more suitable at higher speed rotations than gear. (2) Traction drive can change continuously the distance from the contact point of the rotating part to the axis of rotation; it is useful in continuously variable transmission (CVT). Generally-fixed-reduction-ratio-type traction drive is developed for the purpose of use by high-speed rotation taking advantage of the feature of characteristic (1). On the other hand, the authors have developed a micro drive system for transmission; a micro-traction-drive based on the structure of an angular ball bearing is advantageous over geared speed reducers, for small scale equipment requiring high numbers of revolutions. A micro-traction-drive is easily manufactured by modifying angular bearings and tapered roller bearings for which preload inner race and outer race act as thrust force. The driving force is transmitted by the contact of the retainer with the rolling element in the rotating direction. The test of the experimental model of micro-traction-drive using an angular ball bearing of 10mm inner diameter, 30mm outer diameter, and 9mm width was carried out. Power-absorbing-type test equipment was made and the input and output torque, number of revolutions, temperature, noise, and state of lubrication were measured. With the same test equipment, the micro-traction-drive was compared to the equivalent type planetary gear with outer diameter of 32mm on the market. In comparison with commercially available speed reducers, the planetary gear system, the newly developed micro-traction was found to bear superior performance in terms of allowable transmission torque, efficiency, noise, and other characteristics.

This paper discusses the nonlinear characteristics of the gear coupling derived by tooth contact analysis and the verification test of the analysis method. Tooth contact analysis evaluates the load distribution by solving simultaneous linear inequality derived from compatibility condition of the tooth deformation and balance condition of the force. By applying this method to the gear coupling, we evaluated bending moment and shear force. It was found that nonlinearity of stiffness and damping occurred by the change of contact region of all teeth by load torque or alignment. Rotor dynamics coefficient of the gear coupling was clarified, and it was enabled that the nonlinearity of the gear coupling could be considered for the design of rotating machinery. Next, the tooth stress, bending moment and shear force were measured in the static loading test to verify the analysis method. Analysis results showed the good agreement with the experimental ones, and it was clarified that the analysis method was appropriate.

This paper presents experimental study and numerical simulation of vibration and noise of a speed increaser, which consist of a star type planetary gears and a planetary type epicyclic gear train. The ring mode vibration of internal gear in the star type planetary gears and torsional vibration of planetary gear in the planetary type epicyclic gear train are measured by use of telemetry system. The influence of tooth profile error for the vibration and the noise is clarified. The numerical simulation is also carried out to evaluate the exciting force and it's associated vibration. In this method, the coupled vibration of shaft bending, torsinal and ring mode vibration of the internal gear are taken into account employing modal synthesis method. The simulation results shows a good agreement with the experimental ones. And it is found that the ring mode vibration magnifies the higher order component of gear mating frequency.

At a multipurpose dam, it is necessary to forecast inflow to control flood safely and to operate hydraulic power plant efficiently. In this paper, we propose a method of forecasting the inflow of several hours later by neural network. The correlation is high about the inflow and rain which fell in the dam basin, but it is difficult to forecast by mathematical methods, because the relation is non-linear model. The neural network system can forecast the inflow by learning the past data of inflow and rain in the basin. This system can forecast inflow well after 1 hour or so. However, this system becomes inaccurate rapidly when it tries to forecast inflow at 3 or more hours later, because we use the rain data of the dam basin. Therefore, we also use rain data which is out of the dam basin and in the direction of the windward. The rain data contains information of the rain which will fall at the dam in future. Then, forecast results show that our system is effective.

The purpose of this study is to investigate the effect of misalignment on traction coefficient in case of crossed axle type traction drive. The measurements of traction force were performed using small size experimental apparatus (average roller diameter is 50 mm, rotational speed of driving roller is 90 rpm). And the comparison of experimental results with calculations of the two dimensional thermal non-Newtonian elasto-hydrodynamic lubrication was performed. Following conclusions were obtained (1) Maximum traction coefficient in this test is 0.1∼0.13. There is no difference between the traction drives and conventional parallel type traction drives. (2) Traction coefficient becomes large by increase of either contact force or misalignment.(3)The measured results are compared to the calculation and it is confirmed that the calculation method is practical and useful.

Spin on the contact surfaces between two elements occurs in such diverse machine elements as angular contact ball bearings or continuously variable transmissions adapting traction drives. We experimentally and analytically studied the effect of spin on lubricating oil film thickness on angular contact ball and disk. Oil film thickness was measured under different spin angular velocities for constant rolling velocity and different contact loads using optical interference method. We clarified the effect of spin on minimum and central thickness of oil film and film shape and analyzed thermo-elastohydrodynamic lubrication (TEHL) considering spin under experimental conditions. Analytical and experimental results agreed well.

The purpose of this study is to investigate the effect on oil film thickness and traction coefficient by the sudden change of loaded torque on traction drives. The experimental measurements of oil film thickness and traction force were performed using the optical interferometic observation method. And the comparison of experimental results with calculations of the two dimensional non-steady thermal elastohy-drodynamic lubrication (TEHL) was performed. We obtained that oil film thickness and traction coefficient decrease though the rotating speed of roller and disc increase, and our discussion lead that the reason of the decrease is the effect of the increase of oil film temperature by shear. The consideration of frictional heating improved the accuracy of calculations about oil film thickness and traction coefficient.

Currently in industries, high-speed turbo machineries such as compressors and steam or gas turbines are required to have increased power capacities. Due to this, a large gear size is required which leads to nonuniform temperature distribution. As the result of nonuniform temperature distribution, nonuniform thermal distortion occurs. Change in load distribution due to this thermal distortion is considered to be closely related to scoring and pitting failures. In order to ensure reliability of high-speed gear units, it is necessary to improve the following techniques. (1) The method of predicting the temperature rise of gears and thermal distortion. (2) Tooth correction against thermal distortion. In this paper, a three-dimensional model for calculating the temperature of teeth surfaces and blanks is presented. This model includes the effects of convective cooling by lubricating oil and the change in load distribution due to mechanical deformation. The calculated results of gear teeth temperature and bending stress are in reasonable agreement with the experimental results. It is confirmed that the analytical method is practical and useful.

Currently in industries, high- speed turbo machineries such as compressors and steam or gas turbines are required to have increased power capacities. Due to this, a large gear size is required which leads to nonuniform temperature distribution. As the result of nonuniform temperature distribution, nonuniform thermal distortion occurs. Change in load distribution due to this thermal distortion is considered to be closely related to scoring and pitting failures. In order to ensure reliability of high-speed gear units, it is necessary to improve the following techniques. (1) The method of predicting the temperature rise of gears and thermal distortion. (2) Tooth correction against thermal distortion. In this paper, a three-dimensional model for calculating the temperature of teeth surfaces and blanks is presented. This model includes the effects of convective cooling by lubricating oil and the change in load distribution due to mechanical deformation. The calculated results of gear teeth temperature and bending stress are in reasonable agreement with the experimental results. It is confirmed that the analytical method is practical and useful.

In cross head type marine diesel engines, cylinder oil is supplied at regular intervals and constant quantity from oil-feed holes to lubricate the running surface of piston rings and cylinder liner. Accordingly it is important to determine position of oil-feed holes, timing of oil-feed, running surface profile of piston rings and cylinder liner and so on to make cylinder oil spread wider and form thicker oil film. In this study, the authors examined how the factors influence the extension of cylinder oil using the tester which simulated cross head type marine diesel engines for the purpose of utilizing small quantities of cylinder oil effectively. We found that wave-cut surface of cylinder liner has better spreadability of cylinder oil than honed surface and wave-cut surface with oil grooves has the effect of circumferential spreadability especially.

In the case of large-size marine diesel engines, it is advantageous to measure lubricating condition between piston rings and cylinder liner to prevent scuffing and abnormal wear. The authors have developed the oil film condition monitoring system using electro-conductivity sensor on cylinder liner running surface. This sensor could recognize the condition of oil film formation easily. It was found that when the sensors were attached in 10% stroke area from top dead center, where the lubricating condition is severe, the difference of lubricating condition could be evaluated well. The lubricating condition between piston rings and cylinder liner was strongly influenced by the change of running surface roughness, bot by the change of oil feed ratio in the range of 0.8∼1.5g/PS·hr.

外ケーブル方式を用いたプレキャストセグメントPC桁は, 軸方向筋が連続配筋されていないため, 継目部に局部変形が集中し, 一体構造桁とは異なる挙動を示す. 本研究では, 外ケーブル方式プレキャストセグメントPC桁の局部変形の影響を実験的に明らかにするとともに, 継目部の局部変形を考慮した解析手法を提案し, 実験結果と比較検討を行った. その結果, 本解析手法を用いることで曲げ性状を終局に至るまで精度良く評価できることが明らかになった. また, 数値解析によりスパン/有効高さ比, デビエータ間隔, 載荷形式, セグメント長, コンクリート強度の各種要因を考慮した終局曲げ耐力の算定式を提案した.

Now a time most of young people do not have inclination for science and engineering. Young engineers in company have change in quality for technology. So many technical design section managers in company want to re-educate the dynamics required subjects in university. The author consider the cause for re-education, and show the main cause is the changing in design system in company. It is necessary to improve the technical training system the company should educate young engineers in co-operation closelywith university.

The purpose of this study are to ensure reliability of the power transmission gears, and to predict operating condition of high speed gears especially with regard to temperature distribution in teeth and blanks. The experiments were carried out using power circulating gear testing machine (1100 kW) under ultra high pitch line velocity (∼150 m/s) and temperature distribution in teeth and blanks were measured. By the experiments, the following facts are known. By increasing line velocity, the temperature of teeth increase parabolically and the distribution of bending stress become nonuniform along face width.