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Volume 39 (1977 - 197･･･
- Issue 4 Pages 433-
- Issue 3 Pages 261-
- Issue 2 Pages 143-
- Issue 1 Pages 4-
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Volume 39, Issue 4
Displaying 1-28 of 28 articles from this issue
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The Properties of Discontinuum Model (I) in Small DeformationYasushi YAMAMOTO1978 Volume 39 Issue 4 Pages 433-438
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThis paper describes what properties the discontinuum model (I) of the preceding paper shows under its small deformation. It is very difficult to argue analytically the properties of the particle system with general arrangement. Therefore, this paper discusses the properties of normal particle systems with simple and regular arrangement.
Consequently, it was proved that the discontinum model (I) was able to have isotropic elasticity which was fundamental property of deformable body with small deformation. At the same time, the concrete method for the analysis of deformable body with small deformation was presented.View full abstractDownload PDF (915K) -
Automatic Travelling Speed Control by Detecting Engine LoadNoboru KAWAMURA, Tateshi FUJIURA1978 Volume 39 Issue 4 Pages 439-445
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSAn automatic travelling speed control system of a rotary tilling tractor in response to the load change was experimented. The deflection of the engine governor was detected by a differential transformer and the travelling speed was controlled by changing the swash-plate angle of the hydrostatic transmission with a three positional electromagnetic valve and a hydraulic cylinder.
(1) The control system was not stable when the setting value of the gain constant and the dead zone were not suitable, because the control system involved time delays in the load detector, the electromagnetic valve, the hydrostatic transmission and the rotary tiller.
(2) To make the system stable, a phase lead circuit and a negative hysteresis relay were provided. The negative hysteresis relay advanced the switching off of the electromagnetic valve. The effect of the phase lead circuit and the negative hysteresis relay were examined in the field tests and in the digital simulation.
(3) When the phase lead circuit and the negative hysteresis relay were provided, the system was stable. In the field tests, when the soil hardness changed the engine speed did not change considerably and the system was good enough. However the control system was not sufficient for the rapid change of the tilling depth.View full abstractDownload PDF (1035K) -
Torque Curve Characteristics of a BladeYasuo SHIBATA, Jun SAKAI1978 Volume 39 Issue 4 Pages 447-457
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSAnalysis of rotary tillage process is important for the design of rotary tillers and tractors. As the tillage resistance has complicated characteristics which is related to the soil condition, blade shapes and other reasons, some part of it has not been well understood. The authors selected a Japanese C-shaped blade to study its torque characteristics, particularly from the view point of design technology. Main results are as follows:
1. The torque curve of a C-shaped blade is highly dependent on its boundary condition, which is equivalent to the shape of the upper surface of the soil slice, and is determined by the relative positions of neighbouring rotary blades. Generally the boundary conditions are classified practically into six patterns as shown in Fig. 4.
2. Special attention should be placed on hard soil from the view point of design technology. In the case of hard soil, a quadrilateral model in Fig. 12 might be used to represent torque courves of C-shaped blades.
3. The model is expressed by the maximum torque Tm, the rotational angle θA and θC and the point C′ for the hard soil (cf. Fig. 12).
4. Maximum torque Tm (kg·m) could be expressed by the multiple regression funtions of pa and S as follows:
Tm={2.17pa+0.226S (for pattern I to V) 2.17pa+0.226S+7.1 (for pattern VI)
where, pa=actual tilling pitch (cutting length of straight blade portion cf. Fig. 4)
S=upper surface area of soil slice
5. The angle θA is generally expressed by a linear equation of pa. The equation for the test blade was as follows:
θA=0.32pa+22(deg)
6. The angle θC is approximately 85 degrees for a blade situated at both right and left ends and 62 degrees for the blade situated in the inside positions on a rotary axle.
7. Using location coefficients k1 and k2, the location of the point C′ is expressed by k2Tm and k1θC. The mean values of k1 and k2 were 0.37 and 0.46 respectively.
8. Soil-bin tests showed that the quadrilateral model is effective to estimate a total torque curve of multiple blades on a rotary axle.View full abstractDownload PDF (5596K) -
Effect of the Swirl Chambers Height on Characteristic of AtomizationHiroshi MOMONO, Toshitami OKAMURA, Munehiro TAKAI, Shunich HATA1978 Volume 39 Issue 4 Pages 459-464
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSA study was made on a trial hollow cone nozzle with regards to the relation between various factors of the nozzle (especially swirl chamber height and nozzle core inlet length) and its atomization characteristics.
In addition a spray distribution recording device was developed and the influence of the various factors of the hollow cone nozzle was studied.
The results were as follows;
1) Discharge coefficient (Cl=0) affected the Reynold's number (Re). In the range of this experiment (Re: 1.0×104-5.6×104), the following empirical equation was derived. C∞=Cl=0·exp (T/Re), where C∞ indicated the discharge coefficient under conditions of potential flow. The C∞ increased with the increase in value of h (swirl chamber height). When the nozzle parameter Ω was exactly at 0.4667, coefficient T showed a distinct effect on h. Hence, it may be considered that when the value of Ω is greater than 0.4667, the fixed numaber T is 1002.
2) The effect of the nozzle inlet length appeared distinctly, when the values of Ω is larger than 0.6770. The C∞ showed lower values as the lenght increased.
3) It may be considered that by changing h the nozzle parameter Ω may be changed. As the relation between (h/r) and Ω changed linearly, the following differential equation may be derived. ΔΩ/Δ(h/r)=5.29×10-2
4) The droplet size distribution was clearly influenced by h at a fixed pressure. It was noted that especially in relation to the above, the maximum diameter, mean diameter, their standard deviation increased with the increase in swirl chamber height. Sauter's mean diameter (d0) was shown by the following equation which was obtained from the ratio of velocity at the orifice (v/ue).
d0=93.23+88.80×(v/ue)
5) It was comfirmed that the spray pattern changed from a hollow cone pattern to full cone pattern in accordance with the ascending pressure. And this tendency became extreme as h increased.View full abstractDownload PDF (862K) -
The desirable Selection founded in the present Situation of Agricultural Transportation MachineryKazuhiko KURATA1978 Volume 39 Issue 4 Pages 465-476
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSRecently, Japnese farming is being highly mechanized and industrialized. However the time required for transportation is still keeping high rate among the total farm working time.
Various transportation machineries are sold and yet the most of the machineries are used under undesirable conditions.
Therefore the questionnaire regarding the use of agricultural transportation machinery was hold and through the analysis of the replies of the users, the following results were obtained.
1) The operations of agricultural transportation are classified into eight categories.
2) Many dissatisfactions with the trailers and powered 3 wheel vehicles which are used for only agriculture are found in the replies.
Most of users pointed out the problems of their noise, vibration and safety of the machines
3) Among the eight classified operations of C1-C8, there are a few desirable transportation machines in the operation case of C3 and C6, and there are no desirable conveying machines for the operation case of C8.
4) There are many dissatisfactions in relation to the damage of loaded products with the screw conveyer and the bucket conveyer which are used for conveying the bulk load of grain.
5) An example for the selection of rather suitable transporting and conveying machines is shown in Tab. 10.View full abstractDownload PDF (1839K) -
Hiroshi SHIMIZU, Akihiro KANNO, Yoshio NISHIYAMA1978 Volume 39 Issue 4 Pages 477-481
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe authors measured the physical properties of rice hull which are considered to be useful for the future fuel and obtained the following results;
(1) Decrease values of volatile matter with respect to the temperatures took the maximum at around 250°C (Fig. 3).
(2) A locality differece was recognized in the ash content of the hull, while no local difference and little variation existed in the carbon.
(3) Average calorific values per dry matter and per non-volatile rest were measured as shown in Tab. 6.
(4) A negative correlation of calorific values against ash contents was recognized in the same groups of variety (Fig. 4).
(5) The uneasy volatile matter had a higher calorific value than the easy volatile matter, but this value was much lower than those of hydrocarbon gasses (Fig. 5).View full abstractDownload PDF (751K) -
Delayed Light Emission of Fresh Tea LeavesKei NAKAJI, Yasuro SUGIURA, Yutaka CHUMA1978 Volume 39 Issue 4 Pages 483-490
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe DLE characteristics of chlorophyll of green tea leaves were investigated to use as a means of non-destructive and prompt estimation of the quality of the leaves.
By using the xenon flash lamp as an exciting light source, DLE characteristics of the fresh leaves were obtained as follows:
1. The DLE of fresh leaves presented a dark recovery phenomenon. Recovery of DLE intensity, under the decay periods of 1.0 and 2.0 seconds, was noticed after the dark period of 10 minutes (Fig. 3). The DLE intensity was independent of preillumination period (Fig. 2).
2. The peak of DLE spectrum of green tea leaf shifted toward a wavelength longer than 685nm, due to the self-absorption of the spectrum by chlorophyll (Fig. 4).
Considering this, DLE detector shoud be selected favorably.
3. The DLE of fresh leaves showed light saturation beyond the 1/4 relative exciting light intensity (Fig. 5). Leaf temperature did not affect the level of exciting light intensity needed for the saturation.
4. The leaf temperature has much to do with the DLE intensity of the leaf. The DLE intensity of fresh leaf has a peak at the temperature of 37°C (Fig. 6).
5. Each of ingredient values of leaf color (Hue, Value and Chroma) had a high correlation with DLE intensity of fresh leaf. The DLE intensity of fresh leaf increased with the change of Hue from yellow to green, Value from light to dark color and Chroma from bright to dull color, respectively (Fig. 7).
6. Chlorophyll content of fresh leaf has a linearity with the intensity of DLE. Therefore the quality of tea leaves, so much as the chlorophyll content is used as an index, could be estimated non-destructively and promptly by means of DLE (Fig. 8, Table 2).
Measurement of DLE of back side of a leaf is desirable than that of front side.
7. By using the ratio of (DLE intensity of back side of a leaf)/(DLE intesity of front side of a leaf) as an index of quality of the tea leaves together with the use of xenon flash lamp, the old leaves which remarkably degrade the quality of tea could be separated from young ones.
The mean values of the index were 1 for the young leaves and 1.4 for the old ones (Table 4).View full abstractDownload PDF (1190K) -
On the 1st and 2nd trial machinesSigeru KAWANA, Akira HOSOKAWA, Hiroshi MORISHIMA1978 Volume 39 Issue 4 Pages 491-496
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSResults of an analytical study conducted previously by the authors indicated that the filament-end-picking operation, which is partly still requires manual labour, could be accomplished by mechanical means using a method proposed by the authors. To test the feasibility of this method, the 1st and 2nd trial machines were fabricated successively and their performance was evaluated. From these trial tests, the authors were able to confirm the feasibility of a high performance and fully automated filament-end-picking operation. For practical application, however, the device should be so designed that the filament could be picked at arbitrary length.View full abstractDownload PDF (944K) -
Noise CharacteristicsShigeo UMEDA, Kentaro MOHRI, Toshio MURATA, Shinroku MORITA1978 Volume 39 Issue 4 Pages 497-503
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThis paper describes the noise distribution and its characteristics of the hot air heater used in the vinyl greenhouse. The greenhouse and the heater are shown in Fig. 1, 2 and 3. The noise source is the axial flow fan attached to the heater.
The noise level in the greenhouse is 98-67dB(A) within about 10m from the heater, but less than 55dB(A) at the opposite end of greenhouse. The noise level at the outside of the greenhouse is over 50dB(A) within 20m from the greenhouse.
The high frequency noise decreased with the distance from the greenhouse, but the noise of 200-300Hz caused by the axial flow fan remains high. The effect of noise reduction by vinyl film is very little.View full abstractDownload PDF (958K) -
Digital Pulse VolumeToshitake ARAMAKI, Takemi ABE, Jun YAMASHITA1978 Volume 39 Issue 4 Pages 505-510
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSChain saws have been widely used in Japan, but Raynaud's disease of occupational origin (white wax disease) occured among forestry workers since about 1956.
Main signs of the disabilities resulting from the use of vibrating tools are (1) blanching of fingers (2) numbness of fingers, (3) joint and muscle pains. Among these blanching of fingers (Raynaud's disease) has been considered most serious.
Experimental studies were carried out for the purpose of investigating the effect of mechanical vibration on the blood flow in the digit by using a mechanical plethysmography in three seasons of summer, autumn and winter
Blood flow in the digit was more closely correlated with enviromental conditions than vibratory load. Hanting reaction was highest in autumn. In case of low temperature, the blood flow in the digit was reduced in the following experiments. When such highstringing of vasomotor nerve in sepeated several times, it seems to cause some trouble.View full abstractDownload PDF (816K) -
Consideration of Noise Reflection and Refraction, and Tests of Belt LocationRyuzo TAKEUCHI1978 Volume 39 Issue 4 Pages 511-516
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESS1. Investigation for noise absorption effect of shrub
The continuous increase of the noise level in the community during the past two decades has brought forth a growing awareness of noise pollution. Then, the author studied the noise absorption using vegetation from his preceding report, and performed the calculation of shrub effect.
Then the author have calculated the standard deviation, effective significance and limiting range of the mean absorbing noise for three kinds of plants.
In conclusion, the 3′(0.91m) height from ground had large attenuation of straight noise energy and had excellent stability of noise abatement effects.
2. Interference between the direct sound wave and reflected wave
In order to interpret the systematical variation of the experimental data, an interference pattern between a source and its reflection image was constructed. The noise source was located at 3′(0.61m) height from the ground, which was a value used in most of the experiments. The relative position of the source, its image and the receiver are shown in Fig. 3.
On the result of image and this theoretical consideration, the sound pressure level (SPL) was calculated and computer program was written. The interference patten of maximum and minimum SPL lines superimposing on the inverse square distance law is clearly shown on the three dimensional graph shown in Fig. 4.
3, Belt location test
These tests were conducted to determine the effective location of the shrub barrier between the receiver and noise source (R/S ratio) for selected receiver. The R/S ratio was preset at five levels and relative attenuations were computed with respect to the selected R/S ratio. The results were similar to those obtained by noise test of large forests of the University of Nebraska. However, the lowest relative noise attenuation was observed at R/S ratio of 0.5. The curves indicated that the noise attenuation by shrub was more effective at higher R/S ratio.View full abstractDownload PDF (895K) -
Community Growth Model following the Performance Index of Growth Rate MaximizationKoji TAMAKI1978 Volume 39 Issue 4 Pages 517-522
Published: 1978
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe community model II, presented in this paper, is based upon the idea that photosynthetic organ playing basic and important role in plant growth, is made by the following process.
As plant community grows up, inside light condition of the community changes gradually. To adapt these changes, the plants individually construct space distribution of their photo organ, which is optimal to their existence, according to the performance index of maximum growth rate, and these results influence light condition again.
These is a room for fusther discussion on the assumption that a plant actully makes the structure of photo organ in accordance with the principle of optimality, but in this paper, it is the main subject to investigate the possibility of systems approach to the mechanism that plant community is formed.
Model II is based upon the assumption 1 to 7, explaining the mechanism of plant withering caused by the interaction between photo organ structure and the light distribution in plant community.
By the use of simulation method, the validity of the model is examined from the point of ecological laws, such are known as the constant final yield, logistic growth, competition density effect and distributed structure of species weight in community,
Consequently, it becomes clear that model II represents essential characteristics, required for the subject to be controlled in agricultural production problem.View full abstractDownload PDF (970K) -
[in Japanese], [in Japanese], [in Japanese]1978 Volume 39 Issue 4 Pages 523-527
Published: 1978
Released on J-STAGE: April 30, 2010
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[in Japanese]1978 Volume 39 Issue 4 Pages 531-538
Published: 1978
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[in Japanese]1978 Volume 39 Issue 4 Pages 539-543
Published: 1978
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[in Japanese]1978 Volume 39 Issue 4 Pages 544-547
Published: 1978
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[in Japanese]1978 Volume 39 Issue 4 Pages 548-554
Published: 1978
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[in Japanese]1978 Volume 39 Issue 4 Pages 555-559
Published: 1978
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[in Japanese]1978 Volume 39 Issue 4 Pages 560-562
Published: 1978
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[in Japanese]1978 Volume 39 Issue 4 Pages 563-569
Published: 1978
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1978 Volume 39 Issue 4 Pages 569
Published: 1978
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[in Japanese]1978 Volume 39 Issue 4 Pages 570-573
Published: 1978
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[in Japanese]1978 Volume 39 Issue 4 Pages 574-576
Published: 1978
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[in Japanese], [in Japanese]1978 Volume 39 Issue 4 Pages 577-579
Published: 1978
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[in Japanese], [in Japanese]1978 Volume 39 Issue 4 Pages 580-583
Published: 1978
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[in Japanese]1978 Volume 39 Issue 4 Pages 584-586
Published: 1978
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[in Japanese]1978 Volume 39 Issue 4 Pages 587-589
Published: 1978
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[in Japanese], [in Japanese]1978 Volume 39 Issue 4 Pages 590-592
Published: 1978
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