1,123 research outputs found
Secular changes of air temperature and precipitation in Okayama City.
In this paper, secular changes of air temperature and the amount of precipitation in Okayama city are discussed using observed values at Okayama meteorologiccal station. Special reference is made to 1993 and 1994 in which peculiar changes occurred. The results obtained are summarized as follows: (1) The increasing rate of the annual mean air temperature at Okayama city is 0.85℃/100y. This value is nearly equal to the average of Japan; 0.87℃/100y. (2) The increasing rate indicates seasonal changes, and the rate is high especially in April and May. (3) The rapid increase of the air temperature in the 1980s is due to removal of Okayama meteorological station from the edge of town to the center. (4) The annual mean air temperature in 1994 is 16.9℃, and the monthly mean temperature for July and August are 29.8 and 29.6℃ respectively. These values are new records at the Okayama station. (5) The air temperature in July and August, 1993 are higher than in 1980 when it was much colder in the summer. (6) The amount of precipitation does not show any secular changes
A Representation of Ring Homomorphisms on Unital Regular Commutative Banach Algebras
We give a complete representation of a ring homomorphism from a unital semisimple regular commutative Banach algebra into a unital semisimple commutative Banach algebra, which need not be regular. As a corollary we give a sufficient condition in order that a ring homomorphism is automatically linear or conjugate linear.</p
Surjective isometries on a Banach space of analytic functions on the open unit disc
Let be the linear space of all analytic functions on the open
unit disc . We define by the linear subspace
of all with bounded derivative on . We
give the characterization of surjective, not necessarily linear, isometries on
with respect to the following two norms: and for , where
is the supremum norm on .Comment: 46 page
Livestock Transactions as Coping Strategies in Zambia:New Evidence from High-Frequency Panel Data
This study re-examines the buffer stock hypothesis regarding livestock by taking into account differences in wealth level, asset types, and periods after a shock. This paper takes advantage of a unique panel data set of agricultural households in Southern Province, Zambia. The data were collected by weekly interviews of 48 sample households from November 2007 to December 2009, covering two crop years in which an unusually heavy rainfall event took place. If we consider delayed responses to the heavy rain shock, our econometric analyses support the buffer stock hypothesis for cattle as well as small livestock. Overall, this paper suggests that conventional annual data sets used by existing literature may miss the period-dependent transactions of assets after a shock.Asset smoothing, Buffer stock, Weather risk, Livestock, Sub-Saharan Africa
Improvement of complementary relationship-based evapotranspiration model
Advection-Aridity(AA) model can calculate actual evapotranspiration by using only meteorological data. However, comparing the model with Penman equation showed that AA model doesn’t properly evaluate evapotranspiration from urban moisture area. In urban area, Actual evaporation from water calculated by AA model(E) are much less than that by Penman equation(Epo). Multiple regression analysis using estimation results indicates that the difference between the models is due to the difference of the sensitivity to vapor pressure deficit between the models. To improve this problem, modification coefficient k, defined as k=a・albedo+b, is suggested. Regression coefficients a, b are determined as satisfying k=Epo/E for water and k=1 for urban surface. By using this coefficient k, evaporation from water is nearly equal to value estimated by Penman equation, while evaporation from urban surface is changeless
Comparison of micrometeorological environments inside and outside a watermelon plastic greenhouse
The use of glass and plastic greenhouses have rapidly increased in recent years. Meteorological and soil moisture environments inside a greenhouse are significantly different from those in the open field. These differences should be understandable to establish accurate predictions of water consumption and evapotranspiraton inside a greenhouse which play impotrant roles in the design of any irrigation system. This study aims to estimate the micrometeorological conditions inside a watermelon plastic greenhouse which can be used for evapotranspiration calculations. Therefore, micrometeorological data were measured inside and outside the greenhouse for the comparison purposes. The results of this study may be summarized as : (1) Solar radiation inside the greenhouse was about 70% of that of outside it. (2) Net radiation during the daytime inside the greenhouse was almost the same as the absorbed total short-wave radiation. (3) The difference of air temperature inside and outside the greenhouse was very large during the daytime whereas not much difference was observed during the nighttime. (4) Both relative humidity and saturation deficit inside the greenhouse were higher than outside in case of highly vegetative land. (5) Wind speed inside the greenhouse was almost zero, while outside the average value was 1.8m/s
Tingley's problem for a Banach space of Lipschitz functions on the closed unit interval (Research on preserver problems on Banach algebras and related topics)
We prove that every surjective isometry on the unit sphere of Lip(I) of all Lipschitz continuous functions on the closed unit interval I is extended to a surjective real linear isometry on Lip(I) with the norm ∥f∥σ = |f(0)| + ∥f′∥L∞
Surjective isometries on an algebra of analytic functions with -boundary values (Research on preserver problems on Banach algebras and related topics)
Let , ⁻ and be the open unit disk, closed unit disk and unit circle in ℂ. Let (⁻) denote the algebra of all continuous functions f on ⁻ which are analytic in and whose restrictions f| to T are of class . For each f ∈ (⁻), the k-th derivative of f| as a function on is denoted by D^k(f). We characterize surjective, not necessarily linear, isometries on (⁻) with respect to the norm ∥f∥⁻ + Σ[n][k=1]∥(f)∥/k!, where ∥ · ∥⁻ and ∥ · ∥ are the supremum norms on ⁻ and , respectively
Crop Water Use From Shallow Groundwater -Simulation Using Field Measured Soil and Climatic Parameters-
The SWAP93 model was used to predict how much capillary rise would occur in cropped fields. The experimental fields were located in a humid climate and it was thought that contribution from groundwater sources to total water use could be significant. In one field planted with soybean, the model predicted an average daily uptake of 1.3 mm; in another field planted with pumpkin, there was average daily uptake of 0.3 mm; and yet in a third field located in a vinyl house there was average daily uptake of 0.03 mm. These predictions represent about 38,7 and 1% contribution to total water use respectively. Even though there were no measured data to compare with, the results lie within the range of other works reported in the literature
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