All issues
Volume 38 (2003)
- Issue 4 Pages 199-
- Issue 3 Pages 143-
- Issue 2 Pages 73-
- Issue 1 Pages 3-
Volume 38, Issue 2
Displaying 1-6 of 6 articles from this issue
- |<
- <
- 1
- >
- >|
-
Koichi SHOJI, Fumihiko TANIMORI, Kazuaki NAKAYAMA, Tsuneo KAWAMURA, No ...2003 Volume 38 Issue 2 Pages 73-78
Published: June 19, 2003
Released on J-STAGE: February 09, 2010
JOURNAL FREE ACCESSThe fluctuation of the surface, or relative depth of water within a paddy field, was related to yield and quality of the rice. A 0.5ha-transplanted paddy field having the fluctuation of elevation of about 100mm was used, and the level of water was monitored at several points of observation in the field. Following conclusions were obtained based upon these measurements for two years.
1) There was a slight tendency of greater yields at lower elevations, although it was not statistically significant. The yield components varied among the elevations; at the lower elevations, the number of panicles per hill-plant and the number of grains per panicle were greater, and vice versa the weight of kernel and the percentage of ripened grains.
2) The protein content in the kernel was significantly greater at lower elevations, which can be related to the smaller weight of the kernel and percentage of ripened grains mentioned above. The greater protein content could be also ascribed to continuous intake of nitrogen, as a result of continuous submergence of water on the soil.
3) There was a case that at poorly drained intermediate elevations in the middle of the field, the protein content was as high as at lower elevations. This implied that the management of the water level or drainage was essential as well as the leveling of the paddy field, so as to produce the rice of as uniform and low protein content as possible within the field.View full abstractDownload PDF (1390K) -
Yoshikazu T. YAMAKI2003 Volume 38 Issue 2 Pages 79-86
Published: June 19, 2003
Released on J-STAGE: February 09, 2010
JOURNAL FREE ACCESSOccurence and coverage of under cover plants (UCP) in herbicide-free citrus fields of the University of Tokyo (UT) were observed for three years.
The data was compared with data from other herbicide-applied orchards reported in literature. The purpose of the observation was to obtain data to assist in the development of techniques for ecological weed control.
In the observation of the orchard at UT, fifty five UCP species were found in the nursery tangerine (Citrus unshiu) field, and fifty seven in the hassaku (C. hassaku) field. About sixty percent of the species were common in the two fields. About twenty percent of the species were common in the two fields. About twenty percent were unique to each field.
Climbing plants, plants with high occurence and coverage, and tall plants are harmful to citrus trees, especially to nursery trees. Climbing plants including vines, were difficult to control only by mowing several times a year. Other plants seemed to be well controlled by three to four mowings per year.
Fifteen UCP species in the tangerine field and eight in the hassaku field were common to species in other citrus orchards in literature. Fifteen UCP species were unique to the UT orchard.
Among the UCP species invading the UT fields, some were considered as major weeds in fields throughout the world. No weeds common in paddy fields were seen in the two UT citrus fields.View full abstractDownload PDF (961K) -
Shigehiko HAYASHI, Katsunobu GANNO, Hideto KUROSAKI2003 Volume 38 Issue 2 Pages 87-92
Published: June 19, 2003
Released on J-STAGE: February 09, 2010
JOURNAL FREE ACCESSA voice-control battery cart equipped a spot air-conditioner that can be operated by a worker's voice was developed for the purpose of the improvement of tomato management work in a high-eaves-type greenhouse. The basic performance experiments were conducted in a laboratory and a greenhouse where tomatoes were planted. The following conclusions were obtained from the study:
1) By phonated command, a worker can control the cart's back and forth motion, acceleration and deceleration, the lifter's up and down motion, and the operation of the compressor or fun in the spot air-conditioner. A worker can execute tomato management work without touching the operational panel.
2) When a wired microphone was used in the laboratory, the detection rate and response time of the voice-control battery cart were 85-100% and approximately 1 second, respectively. Moreover, when a wireless microphone was used within an area of 17.0×7.2m in the greenhouse, the detection rate and response time were 90-100% and approximately 1 second, respectively.
3) The cart could be controlled remotely within an area of 17.0×7.2m in the greenhouse. Although some problems, such as delayed response and erroneous recognition of conversation words, remain for improvement, the study showed that use of the voice-control battery cart in a large-scale greenhouse is feasible.View full abstractDownload PDF (1461K) -
Yuichi KOBAYASHI, Kanji OTSUKA, Ken TANIWAKI, Mitsuho SUGIMOTO, Kyo KO ...2003 Volume 38 Issue 2 Pages 93-98
Published: June 19, 2003
Released on J-STAGE: February 09, 2010
JOURNAL FREE ACCESSTo harvest kenaf, a sugar cane harvester that was modified in some parts was used as kenaf harvester. The basic performance, the period when it can be harvested and the effective field capacity of this machine were cleared by the field test. The results were as follows.
(1) A sugar cane harvester harvests kenaf well used by a developed kenaf special cutter.
(2) This machine cut kenaf stems 22cm each regardless of the traveling speed.
(3) This machine was able to harvest well from flowering stage to killing frosted stage. In this study area, it was from mid October to last February.
(4) The effective field capacity of the net bag style was 6.6a/h, and the conveying style was 13.9a/h.View full abstractDownload PDF (1377K) -
Osamu KINOSHITA2003 Volume 38 Issue 2 Pages 99-104
Published: June 19, 2003
Released on J-STAGE: February 09, 2010
JOURNAL FREE ACCESSUse rate of riding tractors equipped with roll-over protective structures (ROPS) was calculated. Trends in this rate were then used to consider measures for bringing ROPS into greater use. The main results were as follows:
1) In 2000, the average time that ROPS had been in use in a tractor was 18 years, and this average was increasing.
2) It appears that in 2000, about 30% of riding tractors were equipped with ROPS.
3) Compared to the foreign countries, Japan began adopting ROPS later, and it is taking longer to come into widespread use.
4) Considering that the ratio of new to old tractors of about 6:4, it appears that requiring ROPS in not only new vehicles, but old ones as well, would bring it into wider use.
5) Cabs are much more effective in preventing fatal accidents than the 2- or 4-pole safety frame. Thus it appears that fatal accidents can be reduced substantially if cabs become mandatory equipment.
6) The suggested retail price of a tractor with cab is 900, 000 yen higher than a tractor without a cab, so it would be difficult to mandate its use without some sort of financial incentive.View full abstractDownload PDF (811K) -
2003 Volume 38 Issue 2 Pages 109-128
Published: June 19, 2003
Released on J-STAGE: February 09, 2010
JOURNAL FREE ACCESSDownload PDF (3385K)
- |<
- <
- 1
- >
- >|