A direct algorithm for state deadbeat control

The authors propose a novel method for computing state deadbeat feedback gains from systems given in the staircase form. The proposed method uses only manipulations of given matrices, and hence is more direct than the existing method, which requires orthogonal transformations repeatedly. It is shown that the obtained gain is linear quadratic optimal for some weighting matrices </p

A construction of multivariable MRACS with fixed compensator using coprime factorization approach

A multivariable model reference adaptive control system (MRACS) with a fixed compensator is proposed. First, a new two-degree-of-freedom (2DOF) compensator with disturbance estimator is derived. Using this structure, a multivariable MRACS with fixed compensator is constructed. Since the proposed method is based on the 2 DOF structure, the fixed compensator is chosen independently of specifications for reference commands. The boundedness of all signals in the closed-loop system and the convergence of the output error are proved. A design method of the fixed compensator for MRACS with low sensitivity is also given. Finally, numerical examples are illustrated in order to show the effectiveness of the proposed method </p

Pericarp Characteristics of the F(1) Hybrid Medium-Fruited Tomato between the Male Sterile Mutant (T-4) of the Large-Fruited 'First' and a Small-Fruited Pure Line with Soft Pericarp

Breeding for a soft pericarp in medium-sized tomato fruit was conducted by crossing the male sterile mutant (T-4) of the large-fruited 'First' and a small-fruited pure line with a soft pericarp (S). Pericarp characteristics of the F(1) hybrid (named MS-II) were compared with the parents and two similar medium-fruited tomato cultivars, 'Red ore' and 'Frutica'. Pericarp firmness in MS-II was lower as compared with that of both T-4 and S. Differences in pericarp firmness among MS-II, 'Red ore' and 'Frutica' were dependent on truss. In the first truss, MS-II developed fruits with a softer pericarp than 'Red ore', but with a firmer pericarp than 'Frutica'. In the second and third trusses, pericarp firmness of the fruit in MS-II tended to be lower than those of the other two cultivars. The thickness of the exocarp cuticle in MS-II was lower than that in 'Red ore', but was no different to that in 'Frutica'. Thus genotypic differences in pericarp firmness among MS-II, 'Red ore' and 'Frutica' seem to be derived from differences in the degree of cutin development in the epidermal perimeter. A thinner cuticle can explain pericarp softness in the fruits above the second truss in MS-II.薄皮果柔の中玉トマト品種育成を目的とし，‘ファースト’花粉非崩壊型雄性不稔系統 (T-4) を種子親，果皮の軟らかい小果固定系統 (S) を花粉親とするF(1)雑種 (MS-II) の特性について，両親系統および既存の中玉F(1)品種‘レッドオーレ’，‘フルティカ’のそれと比較した．両親系統と比較したところ，MS-IIの果実硬度は花粉親である軟果皮Sと同等となり，果皮硬度はSよりも低い値となった．3段摘心栽培において，MS-IIの果実硬度は第1段では2品種と差は無かったが，上位果房ほど両品種よりも低くなる傾向を示した．果皮硬度は，第1果房では‘レッドオーレ’よりも低く，‘フルティカ’よりも高かったが，上位果房ほど両品種よりも低い値となる傾向を示した．MS-IIの外果皮におけるクチクラ厚を測定したところ，‘フルティカ’と同等となり，‘レッドオーレ’よりも低かった．また，MS-IIのクチクラ層の発達程度が2品種よりも低いことが観察され，MS-IIの果皮硬度が2品種よりも低い傾向を示すのは，外果皮におけるクチクラ層の発達程度が低いためと推測された

Large-fruited Tomato Production as Affected by Root-zone Extension and Wick Addition During Cultivation in a Capillary Wick System

This study was conducted to investigate the possibility to use capillary wick system in large-fruited tomato production. The first experiment in the autumn-winter season of 2006 was carried out to investigate the effects of the amount of substrate on growth and yield of tomato. Treatments involved growing large-fruited tomato in one box (2.8ℓ/plant) continuously, or adding substrate at flowering of the 7th truss in a 2nd box (5.6ℓ/plant). Fruit yield was higher when the root-zone was extended with double the substrate volume. The second experiment in spring-summer season of 2007 was aimed at improving growth and yield of tomato by extension of root-zone and addition of wick. Tomato plants were either grown in one box with one wick continuously, or with addition of substrate in a 2nd box at flowering of the 4th truss. Additionally, one more wick was inserted into 50% of the 2nd boxes. Half of the plants were grown in two boxes with one wick, and the other half with two wicks. Higher yield was obtained from the plants grown in two boxes with two wicks, suggesting that fruit yield was increased by increasing water transport through wick addition coupled with root-zone extension. Plant growth and fruit yield of large-fruited tomato was stable without blossom-end rot when root-zone was extended and half strength of Ohtsuka-A nutrient solution supplied through the capillary wick system. There was, however, a slight sign of physiological disorder at the leaf margins similar to potassium deficiency.「防根給水ひも」を利用した底面給水法が大玉トマト生産に適用可能かどうかを検討した．2006年秋ﾝ冬季の実験では，培地量がトマトの生育と収量に及ぼす影響について調査した．大玉トマトを終始1stBox（＝2.8ℓ･plant－1）で栽培する処理区と７段花房開花時に2ndBox（＝2.8ℓ）に培地を追加し，最終的に１stBox + 2ndBox（＝5.6ℓ･plant－1）で栽培する処理区を比較した結果，培地量を２倍にし，根域を拡張した処理区の収量が高くなった．2007年春ﾝ夏季の実験では根域拡張および「ひも」適用本数の増加によりトマトの生育収量を改善出来るかを検討するため，終始 1stBox，「ひも」1本で栽培する区，4段花房開花時に培地を追加し最終的に1stBox + 2ndBoxで栽培するが，そこには「ひも」は配さない区，培地を加えると同時に「ひも」を配する区の3区でトマトを栽培した．その結果，1stBox + 2ndBox，「ひも」2本で栽培したトマトが最も収量が高かった．培地追加時に「ひも」を配することで水輸送量が増大した事が収量増加に繋がったものと考えられた．以上の結果より，生育途中で培地量を増やすと同時に，もう1本の「ひも」を配置して大塚A処方1/2濃度で終始管理すれば，生育中期にK欠乏と思しき葉縁の黄変が見られるものの，尻腐れ果実のほとんど発生しない安定したトマト生産が可能であるといえる