All issues
Volume 53, Issue 4
Displaying 1-14 of 14 articles from this issue
- |<
- <
- 1
- >
- >|
-
R. YAMASHITA1991 Volume 53 Issue 4 Pages 1-2
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (1973K) -
Output Power of Power Bellows Type ModelTsuguo OKAMOTO, Tae Han KIM, Osamu KITANI1991 Volume 53 Issue 4 Pages 3-9
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSLeakage of working fluid from a Stirling engine system is a serious problem. Instead of a power piston, a stainless steel bellows element was applied to a trial-made engine for its power actuator to prevent gas leakage and to decrease friction losses at sealing.
This report described output power performance of the bellows type Stirling engine model and the effects of bellows actuator were discussed. Its indicated power was more than two times as that of the piston type model producing about ten watts of net power.View full abstractDownload PDF (1061K) -
Operation of a Tractor Engine with Dual-fuelNoboru NOGUCHI, Siangtai AN, Hideo TERAO1991 Volume 53 Issue 4 Pages 11-19
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe purposes of this paper were to remodel a conventional tractor engine and to demonstrate the feasiblity of using alcohol as alternative fuel for the farm tractor with diesel engine. To investigate the performance of the dual-fuel engine and the static characteristic of the engine control system, a dynamometer was connected to the tractor through a PTO shaft. The performance of the dual-fuel tractor engine was measured in terms of PTO power, BSHC, smoke density, NOx emission and engine noise. The dynamic characteristic of the engine control system was tested under rapid load changes through the release and depression of a clutch pedal. Furthermore, the field tests using a rotary tiller were carried out. The engine control system provided acceptable engine response to the varying load condition in field operation.View full abstractDownload PDF (3098K) -
Soil Failure during a High Speed Triaxial Compression TestTanya Niyamapa1991 Volume 53 Issue 4 Pages 21-30
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe effect of loading speed on soil failure was studied by using a high speed triaxial compression test. Tests were conducted at 0.35-6.2m/s loading speed to compress soil specimens of silty loam and sandy loam at different moisture contents. The axial stress at fracture and the failure energy per unit volume increased with increase in loading speed up to certain critical speeds, however they decreased as the speed increased further. Two types of soil failure such as brittle failure and plastic flow were noticed which depended on the loading speed. Test soil specimens failed in brittle failure at lower loading speed. The mode of soil failure changed to platic flow at higher loading speed.
The volume of test soil specimen increased with increase in loading speed. In one case the test soil specimen dilated clear on shearing along a slip plane at lower loading speed. In the second case the barreling of cylindrical specimen consisted of the top and bottom conical shaped wedge or only one with small crack or fluidization of soil on all sides of test soil specimen at higher loading speed were observed.View full abstractDownload PDF (3336K) -
Changes in Quality of Chinese Yam Stored in a Commercial WarehouseKazunori HIRONAKA, Ken'ichi ISHIBASHI1991 Volume 53 Issue 4 Pages 31-39
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSChinse Yams were stored in a commercial warehouse (9×11×5m) from November of 1986 to April of 1987 and the changes in quality of the yams were investigated throughout the storage period. The surface of the yams showed a gradual yellowing after about 58 days of storage. Both glucose and fructose contents increased markedly, which resulted in an increase in sweetness of the yams. Moreover, the viscosity of the ground solution of the yams decreased during storage. A significant linear relationship between the viscosity of the yams during storage and the temperature at the center of the yams was observed at the 5% level. Conseqently, the viscosity could be expressed as a function of the temperature.View full abstractDownload PDF (3792K) -
Soil Failure and Shapes of Shanks and ChiselsRui GAO, He Rong YEN, Ken ARAYA, Tsukasa MAEKAWA, Satoshi TSUNEMATSU, ...1991 Volume 53 Issue 4 Pages 41-52
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThere are two design objects in a subsoiler with pressurized fluid injection, that is used as a pan-breaker and as an injector. A large soil failure rate is desirable in the case of pan-breaker and a small soil failure rate in the case of injector. This report deals with the relation between the soil failure rate and the shapes of shanks and chisels without fluid injection.
The results showed that the appropriate pan-breaker without fluid injection should have the rake angle of 45-60°, the shank thickness of more than 15mm, the chisel length of 250mm, and the chisel thickness of 50×50mm. The appropriate injector without fluid injection should have the rake angle of 90°, the shank thickness of less than 15mm, the chisel length of 130mm, and the chisel thickness of 30×30mm.View full abstractDownload PDF (8146K) -
Motonobu URA, Kiyoshi NAMIKAWA1991 Volume 53 Issue 4 Pages 53-59
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSTo eliminate over-application from misdilution, save the cost of agricultural chemicals, and remove agitating power, automatic chemical metering and injecting system was considered and experimented. The range of spraying flow rate was 10 to 30l/min. The range of dilution was wide as 100 to 1000 times. The variance of diluent error was within 7 percents and the offset from the aimed dilution was within 5 percents. Applying this injecting device as an application rate controller of self-propelled sprayers was considered and tested in the laboratory. It was found that undiluted chemical application rate was fairly well controlled within the wide range of 0.5 to 3l/ha.View full abstractDownload PDF (1120K) -
Broccoli Storage TestsGuo-Rong XUE, Toshitaka UCHINO, Masaki MATSUO1991 Volume 53 Issue 4 Pages 61-70
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe effects of the low density polyethylene (LDPE) films mixed with ethylene absorbent or far infrared radiating ceramics and of the moisture absorbent in LDPE bag on the freshness-keeping of broccoli were discussed.
The storage time of broccolis in LDPE bags was elongated over two times than that of non-packaged ones. Yellowing and wilting of broccoli were observed on non-package, and off-flavour was observed on LDPE package. It was considered that this elongation of storage time was caused by the CA storage effect of LDPE bag, and in this study the optimum gas condition was ca. 1.5% O2 and ca. 5% CO2 concentration.
The effects of ethylene absorbent and far infrared radiating ceramics were not evident. The appropriate moisture control was effective to keep freshness, but it was difficult to decide the proper mass of moisture absorbent owing to the correlation of its ability and transpiration of broccoli.View full abstractDownload PDF (1526K) -
Theoretical Equations and the Laws of Proportion for Grain-Impeller DynamicsYoshio NISHIYAMA1991 Volume 53 Issue 4 Pages 71-76
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSGeneral equations of the dynamics between a paddy grain and an impeller blade were expressed in terms of polar coordinates using complex numbers. Grain velocity, force and energy are computed from the dynamics equations for an arbitrary shape of a blade. The following laws of proportion were derived from the dynamics equations.
(1) The law of proportion in terms of rotating angular velocity ω: If the initial grain velocity is proportional to ω or equal to 0, the grain velocity is proportional to ω force and energy are proportional to ω2.
(2) The law of proportion in terms of similarity ratio χ between similar blades with the rotating axis as the similarity center: If the initial grain velocity is proportional to χ or equal to 0, the grain velocity and force are proportional to χ, while energy is proportional to χ2.View full abstractDownload PDF (773K) -
Sei-ichi OSHITA, Hiroshi SHIMIZU1991 Volume 53 Issue 4 Pages 77-83
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe flash method was used to measure the thermal diffusivity of food model (starch gel) and the thermal conductivity was determined. The representative values of thermal conductivity at 15 [°C] were 0.483 [W/mK]:Xw=0.817, 0.447 [W/mK]:Xw=0.735 and 0.462 [W/mK]:Xw=0.640, where Xw indicates a mass fraction of water.
The thermal conductivity at 30 [°C], that is, 0.504 [W/mK]:Xw=0.817, was about 7% smaller than the value, 0.540 [W/mK]:Xw=0.80, reported by Drusas et al.. This difference lies in the extent of irremovable experimental error and the flash method was shown to be applicable to the measurement of thermal property of foods.
Furthermore, 4 heat conduction models were examined and it was indicated that the series model can explain well the heat transfer mechanism within the gel. The intrinsic thermal conductivity of starch was estimated to be 0.247 [W/mK] at 15 [°C] by applying the series model to the gel.View full abstractDownload PDF (1007K) -
Hiroshi SHIMIZU, Sei-ichi OSHITA, Gyonen FUJIYAMA1991 Volume 53 Issue 4 Pages 85-92
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSFor the basis of measuring the elongation of plant leaf, a theoretical equation was presented to determine three dimensional curve length by the use of image processing technique.
The equation was applied to estimate the length of simulated aluminum leaf and the measuring accuracy was examined. The theoretical equation requires the data set extracted from two digital images of curve at different angles to TV camera.
It was theoretically found that the propagation of measuring errors became minimum when the angle between the digital images was 90 degrees. The measuring accuracy was confirmed by the examination using the plant leaf model, and was less than twice as large as the resolution error of digital image.View full abstractDownload PDF (1126K) -
Kunio SATO, Makoto HOKI, Kenji NAKAGAWA1991 Volume 53 Issue 4 Pages 93-98
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (975K) -
Karl Th. Renius, [in Japanese]1991 Volume 53 Issue 4 Pages 99-106
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (3528K) -
T. KOJIMA1991 Volume 53 Issue 4 Pages 107-112
Published: 1991
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (1021K)
- |<
- <
- 1
- >
- >|