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Volume 29 (1998 - 199･･･
- Issue 4 Pages 175-
- Issue 3 Pages 101-
- Issue 2 Pages 51-
- Issue 1 Pages 1-
Volume 29, Issue 4
Displaying 1-8 of 8 articles from this issue
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from unsteady to quasi-steady state operationFumihiko TANAKA, Shun-ichiro TANAKA, Shi-Qing WANG1999 Volume 29 Issue 4 Pages 175-180
Published: March 25, 1999
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSThis study aimed to develop and validate a model for simulating heat and mass transfer in wrapper type cold store from quasi-steady state to unsteady state operation, namely precooling period. The governing equations were solved numerically by the Runge-Kutta-Gill method. Mainly, initial air conditions and cooling capacity of the refrigeration system were used as model inputs. The model was validated experimentally through cooling test.View full abstractDownload PDF (652K) -
The relationship between grain moisture and inductance of coilZaigui LI, Tokumi FUJIKI, Susumu UCHIDA, Shigeki INABA1999 Volume 29 Issue 4 Pages 181-186
Published: March 25, 1999
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSThe aim of this study was to develop a method to measure moisture content in real-time in the drying and processing of grain. High frequency (100-1000kHz), close and limited coils were used as sensors for grain moisture. It was found that response of coil to the moisture content was affected by the three essential elements (rolls N, diameter D and length l) and frequency. The optimal measurements of moisture content were obtained by using coil G (N=180, D=75mm, l=108mm) with 1000kHz. Relative magnetic permeability and inductance of coil varied with frequency and grain moisture. We found the regression equations between inductance and moisture for rice and wheat. In particular, when moisture was in range of 15%-30%, the moisture content could be estimated accurately, with relative error less than 2%.View full abstractDownload PDF (645K) -
Jae-Do SHIM, Yoshiichi OKADA, Yoshinori GEJIMA1999 Volume 29 Issue 4 Pages 187-195
Published: March 25, 1999
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSThis paper reports the development of a reactor using the continuous removal of suspended solids and settling sludges in the aeration tank and activating the metabolism of aerobic microorganisms without using return sludge. Until now, treatments of high BOD concentration like livestock wastewater are diluted with water to meet the low BOD loading of activated sludge systems. Particularly, the regulation of oxygen requirements has caused great difficulties to the treatment mechanisms. Hence, to solve many problems of the activated-sludge process, authors suggested a new model in conjunction with aeration systems. This system is characterized by utilizing intensive aeration pipe with inlets at the lower portion and outlets at the higher portion. Also, to supply oxygen-transfer necessary for bacterial growth, the mixed liquid from the multiple outlets at the upper part of the aeration pipe is trickled and distributed to the liquid surface. As a result, the dense bubbles produced from the intensive aeration pipe are transferred to the settling tank and the organic materials coagulated in bubbles are settled and removed. Then, the dissolved organic materials returned to aeration tank are retreated on aerobic conditions. Consequently, the BOD concentration of swine wastewater in the aeration tank is reduced rapidly.View full abstractDownload PDF (5870K) -
Takayuki KOJIMA, Jiao Yan LIU, Shuji FUJITA, Shigeki INABA, Munehiro T ...1999 Volume 29 Issue 4 Pages 197-203
Published: March 25, 1999
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSDuring transport the quality of fruits is influenced by vibration, road conditions, shipment distance, and other factors. To better understand these sources of losses, the present study measures the level of vibration involved in the refrigerated transport of strawberries in a truck under road conditions corresponding to, a plain road, a slope road, a road with joints, one over a bridge and one through a tunnel.
In the laboratory experiment, controlled vibration was given to the strawberries from a machine. This machine was operated with a vibration pattern obtained in an earlier test where strawberries were transported by a truck from Saga to Osaka on the highway.
From measurements of the sugar and ascorbic acid contents the quality of strawberries treated with vibration, has been observed to deteriorate remarkably compared to that without any such treatment.
Among three positions on the pallet of the truck, the position-2 was mainly analyzed. The power spectrum is found to peak at 3.35Hz for the plain road and the corresponding acceleration ranges between about 0.0 to 2.0m/sec2. The power spectrum has been found to be different for different road conditions.View full abstractDownload PDF (1123K) -
Elasto-plastic earthquake response analysis to longitudinal directionHideo OGAWA, Ichiei TSUGE1999 Volume 29 Issue 4 Pages 205-214
Published: March 25, 1999
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSLength of longitudinal direction in glass greenhouse becomes longer by expansion of house area. We did elasto-plastic earthquake response analysis about the case that earthquake ground motion was transmited to longitudinal direction. The combination of response analysis with 1) length of longitudinal direction, 2) number of span direction, 3) difference of roof brace stiffness, 4) the speed that an earthquake wave transmited, 5) kind of earthquake wave.
The maximum of response analysis result was 67.6mm about displacement between the pillars which were next to and was 68.9mm about displacement as one pillar. Maximum response displacement as one pillar was about 3 times of greenhouse structure standard.View full abstractDownload PDF (1092K) -
Hiromichi TOYODA, Hideki MORIYAMA, Tomoyuki SENO, Takaaki MAEKAWA1999 Volume 29 Issue 4 Pages 215-223
Published: March 25, 1999
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSFor a low-cost and a resource-saving design of a plastic greenhouse, a simple pile foundation to prevent wind damage was examined.
The horizontal tension test was carried out for a small square steel pipe with a width of 45mm, which is generally used for part of the structure material of a plastic greenhouse. The results showed that the analysis method of the beam on a semi-infinite, ideal elastic medium is applicable to the calculation for a horizontal subgrade reaction of the small pile width.
Moreover, we examined the pulling resistance of the pile, which is reinforced by a small steel pipe arranged in parallel crosses. This result suggests that this pile structure is useful for the method of a simple and low-cost reinforcement of the greenhouse foundation.View full abstractDownload PDF (2516K) -
Katsumi ISHIKAWA, Hiroshi NAKAMURA1999 Volume 29 Issue 4 Pages 225-229
Published: March 25, 1999
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSNutrient pH is related to the plant growth and nutrient components, but it is not easy to control the nutrient pH. In this study, based on the characteristics of the quartz porphyry, which create a pH-buffer and ion exchange actions due to its negative charge. Water production having pH-buffer action was investigated by an effective water treatment system (HITEC-TYPE). As the result, The pH of the nutrient was not rapidly changed, and was maintained in a stable condition at about 7.0 even with the addition of alkaline, and the EC was not reduced.View full abstractDownload PDF (2248K) -
Facility Specifications and Ice-making PerformanceHisashi KOWATA, Yoshikazu SATO, Shinji HOSHIBA, Susumu TAKAHASHI, Isao ...1999 Volume 29 Issue 4 Pages 231-238
Published: March 25, 1999
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSA commercial-scale ice pond refrigeration system was designed and built at Tokachi, Hokkaido, to store 180 metric tons of potatoes until next July following the harvest. The system was capable of producing an ice pond of 1200m3 capacity of dimensions 26m in length, 18m in width, and 3.5m in depth. The ice-making performance of the system was tested during two winter seasons. The final height of the ice pond was about 3.1m, and its volume was approximately 970m3. Although the expected ice volume was 1200m3, the two consecutive relatively mild winters of the testing period prevented from attaining the optimum dimensions of the ice pond. The average volumetric thermal purity of ice, as measured by the ratio of latent heat of fusion of produced ice per unit volume to that of pure ice, was in the range of 0.76 to 0.78 which showed relatively high thermal quality of the ice. The average electric cost of producing an unit volume of ice was 100yen·m-3, which demonstrated the cost-effectiveness of the system.View full abstractDownload PDF (5696K)
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