The advances and retreats of the Alpine glaciers show a surprising correspondence to the up and declined states of the tree-growths at Arlieshan Mt. (23°30′N 120°48′E 2676M) in Formosa, as shown in Fig. 3. It is supposed that the intensified state of would result the retreat of glaciers in the Alps, activating the lateral mixings of cold and warm air, while, in the Far East, the stronger jet would repress the amount of summer precipitations of the south-eastern monsoons on which tree-growths might depend. (See Fig. 2)

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In discussing the structure of typhoon before, the author pointed out the existence of a maximum of wind velocity, that is, a sort of , just at the outer side of the tropopause funnel which forms the eye of typhoon.. The associated with the general circulation of the atmosphere seems essentially to be the same as that with the typhoon. Therefore the author tried to explain the phenomenon, adopting the following four assumptions: (A) stationary, (B) uniform in one direction, (C) frictionless, (D) autobarotropic, and deriving integrals from the initial equations of motion including inertia terms, in the same way as in the previous paper. The integrals represent respectively the law of conservation of (angular) momentum, vorticity and energy.
From the law of co n servation of energy can be derived an equation which determines the form of the surface of discontinuity. The surface inclines the steeper, the smaller the temperature difference and the larger the wind velocity difference between the both sides of the surface. In the neighbourhood of the surface, however, develops a mixing layer at the same time owing to the discontinuity of wind velocity. The thickness of the layer becomes the larger, the smaller the temperature difference and the larger the wind velocity defference, that is, the steeper the surface inclines, the larger the mixing, l ayer becom es in thickness.
From the law of conservation of vorticity it results that there must exist convective motions in the meridional sect ion of the atmosphere. Now, air particles displacing northward get extremely stronger in west wind velocity as they, approach the axis of the earth, as momentum is conserved along a streamline in an air mass. The strong wind thus developed draws down the surface of discontinuity lying above it a nd draws up that lying beneath. It follows thus that air particles can not proceed on their way over some extent northward, owing to the barrier which they form themselves. In, this way, th e meridional circulation of the troposphere presents necessarily a cellular strU. cture, and the air in lower latitudes can not arrive directly at the pole. Oil the other hand, the effect of fri ction is the most intense and, the, mixing layer becomes the largest at the northern end of the cell thus formed. The exchange of a ir between lower and higher latitudes is carried out only through friction. Thus the is developed the northern part of each cell, that is, at the northern end of the southern side of the mixing layer.
The structure of the thus derived is, shown in the figures. These figures, which are derived theoretically, coincide very well with those analysed hitherto by many investigators.

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The pressure, temperature, and density fields are theoretically derived from such a wind field that may be observed in the , and the outstanding features of the are theoretically explained. Especially theoretical relation between the and tropopause, which agrees with the observational results, is found.

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A Computational Fluid Dynamics (CFD) study on the - propulsion of rigidly oscillating and undulating bodies has been undertaken, by the unsteady solutions to the two-dimensional incompressible Navier-Stokes equations in conservative form, which are discretized with the finite volume method, using the pseudo-compressibility technique. Computational validation confirmed that the present method was capable to reasonably predict highly unsteady flows of biological problems. Numerical study on an oscillating hydrofoil (NACA 0012) reveals that there exists a problem of optimal propeller efficiency in generating the - in wake, but within a narrow region of the Strouhal numbers. Further analysis on a tadpole-shaped object and a fish-like body swimming in realistic kinematics, shows that the kinematics effectively produces a - propulsion with much higher propulsive efficiency than that of achieved by the oscillating hydrofoil. Investigation of Reynolds number effect for the undulatory swimming indicates that the propeller efficiency increases with increasing Reynolds number with no Re ceiling in generating the -.

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The effects of the impact angles of an abrasive water jet (AWJ) stream on the depth of groove and the worn volume of Si₃N₄ ceramics have been studied. Two kinds of Si₃N₄ ceramics, β-Si₃N₄ and α′/β′-Sialon, were eroded by AWJs using two kinds of particles, Al₂O₃ (WA) and SiC. The angles of the , which correspond with the angle of an abrasive nozzle, to the specimen were 45°, 60°, 90°, 120° and 135°. The effects of the angles were very different according to the particle. It was suggested that this difference was caused by the difference in fracture strength between the particles. The groove depth and the worn volume were strongly affected by secondary wear, when the particle was SiC. Considering the uniformity of groove depth and width, the best angle of the abrasive nozzle to cut Si₃N₄ ceramics was thougth to be 90°.

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Economical power generation is expected from a since it has about 30 times higher energy density than other renewable energies. Moreover, Japan is most blessed with the energy in the world. We started research on power generation in 1993. Experiments with small-scale flying platforms are included in it. A summary of the studies and the experiments is described.

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1958年12月には,亜熱帯ジェット流は,始め北アメリカで,次いで月末には,西ヨーロッパで大規模に中高緯度へ侵入した。この大規模変位と,それに関連した熱帯ジェットの振舞いが,大気大循環との関係に留意して述べられる。
大規模変位をもたらすきっかけは,ヨーロッパと北アメリカとで異なるが,何れの場合も,中高緯度大気が低緯度大気に及ぼす作用が重要である。
中緯度へ侵入した亜熱帯ジェットの尾根の前面では寒気が大規模に流出し,変位した部分はここで切断される。切断されて中緯度に残された部分は,侵入した亜熱帯高気圧の衰退と共に消失する。
亜熱帯ジェットの大規模変位により,中高緯度大気と低緯度大気との間で大規模な相互干渉が行われ,特に,中高緯度の大気大循環は大きい影響を受ける。
キューバ附近,日本附近及びアフリカ北部では,通常の位置にある亜熱帯ジェットの低緯度側に,冬季,時として別の強風核が観測されるが,これは比較暖い海面上で,低緯度深く達する強い寒気流出と関係がある。

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A database for light-trap catches at 69 sites and density maps for the immigration of long-distance migratory planthoppers into Japan were developed on a personal computer. Geographical distribution and density gradient of immigrants during Baiu season in 1980 to 1985 were analyzed. There were 32 immigration waves of white-backed planthoppers detected, 24 cases showed a close correlation between the developmental scale and localization of low-level (LLJET) and the immigration areas. These immigration areas shifted from the Pacific Ocean to Japan Sea coastal areas in response to the localization of LLJET.

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The convective flow conducting heat from the inner core of the earth to the mantle may follow a --like pattern in which trapped segments of fluid form cylindrical rotating columns—as observed in laboratory studies in cylindrical rotating vessels. This suggests a very simple hydromagnetic version of the dynamo theory in which bundles of magnetic lines of force twisted by the rotation of the outer columns play a predominant role. The westward drift of the convection pattern is a reaction to the eastward drift which the imparts to the inner core. This drift bends the bundles of force lines in such a way that the twisting provides the curl H (near the equator) which supports the earth's main field. The dynamo action tends to produce a main dipole moment parallel to the axis of rotation and effects that are intrinsically fairly small are proposed to account for the present inclination between them. One such effect is inhomogeniety of the temperature distribution and conductivity of the mantle due to convection related to continental configuration. Another arises from irregular kinking of the almost axial bundles of lines of force threading through the solid core and twisted by its rotation relative to the mantle. It is thus plausible that magnetic and rotational axes have remained nearly parallel so that paleomagnetism approximately traces the course of the kinematic poles. Field reversal and continental drift are also briefly discussed.

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 The complex over the Pacific is comprised of multiple Jet Streams which form, intensify and weaken in differing manner depending upon the synoptic situation and area. Regional differences within the Pacific are discussed. The axis of seasonal “strong” winds is determined and compared to the mean position of the principal baroclinic zone. Multiple systems are related to multiple baroclinic zones and characteristic temperature ranges of these zones are delineated and compared to values given for North America. Specific thermal and contour height ranges at the 500 mb level can be identified with each of the multiple systems. The distribution and incidence of “strong” wind velocities at the 500 mb level with certain 500 mb contour heights and temperatures is demonstrated for selected stations in the Pacific. Use of these thermal-contour height ranges as an aid in identification,location and forecasting of the complex is emphasized.

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The authors have developed a non-oxidizing heating system. The newly developed device, which is called an N₂ jet heater, uses the principle of a storage type heat exchanger. By means of employing a set of two heaters, each containing a regenerator, it is possible to heat N₂ gas to 1773 K. The high temperature nitrogen gas maintains a high furnace temperature under non-oxidizing condition. This system has been applied to the tundish heater of a real continuous caster. As a result, the rate of occurrence of inclusion-related defects in the quality of start slab has been reduced to one-fifth to one-third of the past level. This paper presents an outline of the device and describes the effect of its use on steel quality.

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The results of an experiment on the MU radar to observe VHF radio wave scattering structures around the and frontal disturbances in the upper troposphere and tropopause region are reported. The experiment used spaced antenna techniques which can provide high resolution measurements of the wind vector and of the spatial scales and orientation of the structures which are generally associated with turbulence. The main spatial scale parameter examined here was the angular distribution or aspect sensitivity of the scatter. The orientation of the scattering was found in both the vertical and horizontal planes. Rapid variations of scattering orientation in the vertical plane were observed which can be expected to influence high time resolution velocity measurements, particularly vertical velocity. In the horizontal plane, the orientation of scattering structures showed some relationship to wind minima and shear features.

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 Wind and temperature data from a specially instrumented B-29 aircraft, operating near 400 and 300 mb, are used to test the thermal wind equation in the vicinity of a middle-latitude . Analyses of the data at the two levels are presented with respect to both the small and large-scale distribution of wind and temperature. The geostrophic wind shear between the two levels is calculated for horizonal temperature gradient computed over varying distances, and these are compared with the vertical shear obtained from aircraft-measured winds at the mid-point of each interval over which the temperature gradient is measured. The flow patterns at the two levels are considered in determining the ageostrophic components of the wind due to curved flow, and these corrections are applied in the final comparisons of calculated and aircraft-measured shear. A method using averaged winds at the lower level of the layer suggests that this may be a more representative reference than “spot winds” for approximating the wind above when using the thermal wind relation.

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It is the purpose of this paper to make clear the effect of topography upon the . As the numerical example, the strong over the Far East is discussed quantitatively in connection with the Himalays. The fundamental concept we used is that the stationary pattern is obtained if η+αh (η: absolute vorticity, α; constant, h: height of the topography) coincides with the stream function. The difference of roles of topographical effect upon the stationary pattern between the Himalayas and the Rocky mountains is also discussed.

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The present study evaluated the risk in cardiac patients of rupture of a plaque by a from the arch cannula. The entire thoracic aorta and cardiac function were routinely monitored by transesophageal echocardiography (TEE) in 88 adult patients who underwent coronary artery bypass surgery. The changes in the atheromatous plaque in the distal aortic arch were observed before and after cardiopulmonary bypass. Of the 88 patients, 13 were found to have preoperative atheromatous plaque at the distal aortic arch and 8 (61.5%) of them suffered plaque rupture caused by from the arch cannula. Only 1 patient experienced apparent embolic episodes manifesting as cerebral and left leg embolisms; the remaining 7 had no clinical embolic symptoms. In order to prevent atheroembolic events, attention should be paid not only to the ascending aorta, but also to the distal arch and in this regard TEE is useful for detecting atheromatous changes of the aorta. (Jpn Circ J 2001; 65: 161 - 164)

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In recent years, as a new application technology of jet pumps, attention is paid to a method of installing a jet pump at the bottom of a contaminated lake or a river to remove pollutants and promote purification. The large flow rate that can be generated by the jet pump supplies dissolved oxygen in the water to the stagnant area. As a result, underwater bacteria are activated, and contaminants are decomposed and removed by the activated bacteria. In this research, we aimed to pursue the structure and operating characteristics of a jet pump that consumes less power and can generate jet flow with larger flow rate. The jet pump used in this experiment consists of one or more primary nozzles and a secondary nozzle for flow amplification and is installed at the bottom of a large tank. By measuring the flow velocity distribution blown out from the secondary nozzle, the flow rate flowing out from the secondary nozzle is obtained, and the flow rate amplification factor which is the ratio with the injection flow rate of the primary nozzle can be calculated. In this research, the performance difference between a system consisting of one primary nozzle and a system consisting of two or more primary nozzles was experimentally investigated. As a result, knowledge on the optimum supply system of the primary jet was obtained.

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The promotion of - diffusion may enhance the efficiency of mechanical performance in various industrial devices such as fluid machinery and combustion equipments. Both active and passive means were applied for the control of jet streams. Our previous studies disclosed that diamond-shaped cylinder bundles produce a self-excited oscillating - flow field having multiple uniform flow-rate groups. The present visualization work deals with flip-flop flow oscillation from a diamond-shaped cylinder bundle with wall concavity. It is disclosed that the wall concavity has induced a substantial change in the flow patterns in the exit - field with strong turbulence and - dispersion.

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The winter response of the Asian to global warming is investigated using the Coupled Model Intercomparison Project Phase 5 (CMIP5) multi-model dataset under the RCP4.5 scenario. We first evaluate model performances in reproducing the current climatology in the upper troposphere and select the best 27 models. A multi-model ensemble projection by the selected models indicates that the over the Indochina peninsula and the South China Sea is intensified on its equatorial side in the late 21st century, while the shifts poleward over the Eurasian continent and the North Pacific. The strengthening of the on the south side is associated with cyclonic (anticyclonic) circulation anomalies in the upper (lower) troposphere over the southern part of China and decreased upper tropospheric divergence over the Maritime Continent. The strength of the upper tropospheric divergence and the amplitude of the anticylonic eddy streamfunction are strongly correlated. These findings suggest that future changes in the are related to the weakening of a Matsuno-Gill response to tropical heating.

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The Olfactometer (JSO), a newly developed smell stimulus device, is designed to reduce odor contamination that can occur with T & T olfactometry. The detection and recognition thresholds measured by JSO and T & T olfactometry using three odorants are highly correlated. We assessed the clinical usefulness of JSO using five odorants commonly used in standard olfactory examinations in Japan. Subjects were 354 normal and 356 olfactory-disturbed patients. No significant difference in detection or recognition threshold was seen between JSO and T & T olfactometry for either group, indicating that the JSO is effective in olfactory threshold testing and provides an alternative to T & T olfactometry.

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