This letter proposes a new retransmission persistence management scheme for selective repeat automatic repeat request (SR-ARQ). By considering the overall traffic load that has to be managed by SR-ARQ, the proposed scheme arbitrates the retransmission persistence to prevent an abrupt delay increment due to excessive link-level local retransmissions. OPNET simulations show that SR-ARQ performs better with the proposed scheme than with a fixed value of retransmission persistence in terms of the throughput of transmission control protocol (TCP).

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Blocked sugars bearing a 2-nitrovinyl, 1-cyanovinyl, 3-nitrochromen-2-yl or 4-cyano-chromen-2-yl group have been prepared. Their cytotoxicity and chemotherapeutic properties depend on the structure of the sugar moiety. Some of these compounds active against Polyoma virus constitute leads for the development of new antiviral drugs.

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Objective For patients with Parkinson's disease (PD), driving is challenging due to an impaired motor function and decreased attention capabilities. This study assessed the driving capacity in PD patients by comparing neurological signs.
Methods The driving ability of PD patients was evaluated using a driving simulator (Safety Master NT-932) that tested the reaction time in response to traffic signals and steering wheel errors. We studied the correlations between the total Unified Parkinson's Disease Rating Scale (UPDRS) score, the UPDRS part III score, the subscores of the UPDRS part III score, age, PD disease duration, braking reaction time, steering wheel errors and total scores for driving safety test results. 'On' state regular PD licensed drivers (n=42; mean age: 63 years) in Hoehn and Yahr stages II-III participated after their cognitive status was confirmed using mini-mental state examinations.
Results The UPDRS scores, the UPDRS part III scores and the postural instability subscores exhibited significant (p<0.05) correlations with the number of steering wheel errors but not with the braking reaction time or the total safety scores of the test results.
Conclusion The UPDRS is an established evaluation method used to estimate PD signs, although it is not sufficient alone for deciding whether PD patients should be allowed to drive. Our findings suggest that determining the driving ability using a driving simulator might be a useful adjunct to UPDRS scores in the assessment of PD patients who are active drivers. Estimating the driving ability requires complex measurements, including motor performance with perception of stimuli and attention.

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Employing fractional frequency reuse (FFR) in OFDMA cellular systems is very attractive since it offers large capacity and single cell frequency reuse. However, its performance in practical environments, e.g. scheduling and arbitrary cell configurations, has not been well revealed. This paper analyzes the theoretical capacity and outage rate of an OFDMA cellular system employing FFR. Numerical examples show that FFR achieves higher capacity than the non-FFR equivalent when the outage rate is low.

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 Due to global warming, it is concerned that cooling water for thermoelectric generation would be run short more frequently in many places of the world. We used a Computable General Equilibrium (CGE) model to quantify the socio-economic impact of a hypothetical shock of capital productivity, which represents shortage of cooling water on thermal power generation plants. The result showed that the magnitude of electricity generation change and subsequent economic indicators change due to 1% capital productivity reduction were varied by region. The mean electricity generation loss was largest in Southeast Asia and smallest in North Africa when an identical shock was given to all regions throughout the simulation period. Considerable regional differences in GDP and electricity price were attributed to not only the capital productivity, but also the amount of capital in thermoelectric sector and its contribution for GDP. Additionally, thermoelectric sector shock propagates into the global economy. These finding demonstrate the significance in quantifying the economic consequence of cooling water shortage.

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By installing the various types of cells, imbalance in traffic load and excessive handover among cells in a heterogenous network can be prevalent. To deal with this problem, we propose a mobility-based cell association algorithm for load balancing in a heterogenous network. By defining a dynamic system load as a function of the mobility of mobile stations (MSs) and the transmit powers of cells, the proposed algorithm is designed such that it can optimize a utility function based on the fairness of the dynamic system load. Simulation results verify that the proposed algorithm improves the user perceived rate of MSs located at cell edges with slight increase in the number of handovers compared to a conventional cell association based on received signal strength.

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ホテイアオイは，多くの場合人為によって新しい環境へ導入され，世界最悪の侵略的外来種の1つとされている。同種は，とくに栄養塩類が集積した環境でたいへん早く繁殖する。自生植物の生息地は密生する同種による侵入を受けると消滅することがある。本研究は同種の急速な増加の要因の解明を，タイ，チェンライ県にあるノン・ボイ・カイ禁漁区において，水域周辺の土地利用／被覆，水質の解析から試みた。また，2つの高度（30m，90m）から撮影したUAV画像を用いて作成した植生図によって同種の分布を明らかにした。その結果，水域における栄養塩類の集積が同種の急増をもたらしたことが示唆された。2009～2018年の間における土地利用／被覆の変化は，農地の急増を示した。高度90mからの正射投影UAV画像は，湖水の13.82％を同種が覆っていることを，また，高度30mの正射投影UAV画像から作成された植生図は，同種が他の自生種を圧倒して生育していることを示した。本研究は，湖周辺の土地利用／被覆の変化が水質の変化をもたらし，それが同種の急増の主要因であることを示唆した。また，異なる撮影高度の正射投影UAV画像はホテイアオイ及びその他の植物の分布の把握に有効であった。

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Adhesive resin is the important material to bond the strengthening material with concrete substrate and transfers the force between two materials. Adhesive layer plays a major role for debonding strength. This study attempts to find a way to enhance debonding strength through investigating the influence of adhesive layer property, such as thickness and inclusion of FRP sheet on the bond behavior between UFC and ordinary concrete (for concrete cohesion failure), and the bond between steel and steel (for adhesive layer failure) under direct shear test by using nonlinear finite element analysis. The results indicate that adhesive thickness strongly affect the debonding strength. However, FRP sheet inserted to adhesive layer shows small effect on the debonding strength.

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A brief review of the developments in the design and performance of electric d.c. motors suitable for servo systems is given, and graphs of power rate against angular velocity times the square root of the rotation inertia show how the designs have advanced rapidly in recent years. A comparison is made with the power rates of hydraulic motors, showing the latter to still have significant advantage. A basic, approximate mathematical analysis of the servo-loop for each case is presented, showing the similarities of the block diagram and transfer function for the case of velocity control. Obervations are made about the sensitivity to load disturbance and speed of response. The conclusion is that the hydraulic servo could still be a strong competitor, providing that care is taken with the shaping of the control loop. Overall cost is likely to be in favour of the electric drives.

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Artificial cracks were made in the cover concrete of specimens embedding ten types of steel rebars having different Cr contents with the aim of developing Cr-bearing steel rebars resistant to macrocell corrosion environments induced by cracking in cover concrete. The cracks were subjected to intensive penetration of carbon dioxide (carbonation specimens) and chloride ions (chloride attack specimens) to form macrocells. Both groups of specimens were then subjected to accelerated corrosion curing, during which the macrocell corrosion current density was measured. The corrosion area and corrosion loss were also measured at the end of 105 cycles of this accelerated curing. In a macrocell corrosion environment induced by localized carbonation, the minimum Cr content of rebars required for corrosion resistance was 7%. Rebars with a Cr content of 11% were proven corrosion-resistant in a chloride ion concentration macrocell with a concentration difference of not more than 3 kg/m³.

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Thermogravimetric (TG) data on reoxidation behaviour of a particular type of sponge iron (coal based sponge iron) are mainly reported in this paper. While emphasis is on isothermal kinetics, some nonisothermal TG data are also presented. The data have been analysed using the reduced time plot and the activation energy values evaluated using both integral and differential approaches. The kinetic analysis developed has been used to establish the reaction mechanism which is found to be essentially of the first order. The paper also discusses the general importance of high temperature studies in the assessment of reoxidation behaviour of sponge iron and how the outcome of this investigation may be useful for devising means to protect sponge iron against reoxidation and spontaneous combustion.

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この断層・構造帯は古くインドシナ変動によって形成されたものであるが,燕山・ヒマラヤ変動においてもなお活動的で,中生代〜新生代における中国東南部の変動に対応していくつかの時相や活動期を区分することができる.断層運動の特徴は,圧縮性の剪断と引張り性の剪断とが交互している点である.また断層運動は,中国東南部の隆起の進展に伴って弱くなっていった.熊山変動やジュラ紀〜白亜紀の貫入岩・噴出岩は,この断層運動に規制されて,いくつかの時期に生成されたものである.またこのような断層運動の繰り返えしによって,カレドニア変動時代の変成岩や前期古生代のミグマタイトの形成,および後期古生代の堆積岩類の分布などか規制を受けているばかりか,さらに中生代〜新生代における赤色岩や第四系の堆積盆地,温泉・地震・地形などのすべてが規制されている.

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哺乳動物の硬組織を構成するアパタイト結晶では, 炭酸イオンやHPO₄^2-などの異種イオンを結晶格子内に置換している。今日までのところ, 象牙質結晶の格子組成と溶解度積に関する知見に乏しいため, 本報においては, ヒト象牙質を試料として一連の検討を行った。象牙質材料は永久歯と乳歯それぞれの歯冠部より採取した。実験に先立って, 採取試料を乳鉢中で微粉砕し, 低温灰化法 (約60℃) により脱有機処理した。結晶格子組成モデルは (Ca) _5-x (Mg) _q (Na) _u (HPO₄) _v (CO₃) _w (PO₄) _3-y (OH) _1-zであり, 象牙質結晶表面に存在する不安定画分と結晶格子内部に位置する安定画分とを区別した一連の化学分析結果に基づき, 各イオンの組成を示す係数を算出した。象牙質試料は希薄リン酸溶液 (固液比は100mg/100ml), 一定の温度 (25℃) とCO₂分圧下で最長28日間にわたり平衡化した。分析結果においては, 永久歯と乳歯より採取した象牙質結晶の組成に明らかな相違が認められ, 結晶格子組成モデルに基づき求められた溶解度積 (K_DN) についても, 1.8% CO₂分圧下で4.11×10^-45 (永久歯象牙質) と1.74×10^-43 (乳歯象牙質) の値が求められた。特に, 象牙質結晶の溶解度は1.0から3.3%のCO₂分圧下でほぼ同じ結果が得られた。ただし, この特定のガス雰囲気以外の条件下では, 象牙質結晶と見かけ上, 平衡化に達した段階においても, 上記の溶解度積から大きく逸脱した溶液組成をもつことが確かめられた。

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The effect of rare earth on the solidification structure of 3.2%Si-0.9%Al non-oriented silicon steel was investigated using industrial trials. The outputs demonstrated that increasing rare earth content leads to a decrease in the average size of equiaxed crystals in the casting billets. In order to further understand the rare earth on the grain refinement of δ-ferrite, the conventional inclusion detection technology, was used to investigate the distribution characteristics of inclusions, together with theoretical calculation of the equilibrium partition coefficients, pinning forces and mismatch degrees. The detection results of inclusions and the calculation results of pinning force showed that the effect of rare earth on the pinning force of inclusions was marginal. Thermodynamic calculation indicated that Ce addition had negligible effect on the equilibrium partition coefficient of Si, Al and Mn. Combined with the calculation results of GRF model, it is reasonable to consider that the contribution of rare earth element to the refinement of equiaxed crystals can be ignored. Further, the outcomes obtained from the E2EM model calculations revealed that the principal mechanism responsible for the refinement of equiaxed crystals through rare earth treatment can be attributed to the heterogeneous nucleation effect of (La, Ce)₂O₂S.

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The fern genus Pyrrosia Mirbel is revised and enumerated for all the Asian species, as well as some species from neighbouring regions, with an artificial key to all the species recognized. Sixty-four species are distinguished in a rather splitted conception for further biosystematic analysis. Three species, Pyrrosia ensata, P. shennongensis, and P. fuohaiensis are new to science from China.

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A durability test of the implantable Left Ventricular Assist System EVAHEART was conducted to demonstrate that the EVAHEART Blood Pump can be run for 2 years without failing. This testing was useful to indicate potential for BTT and possibly DT applications. We developed a custom durability test mock circulation loop which generates a pulsatile flow simulating the native left ventricle. This mock circulation loop includes components which mimic the left ventricle (LV chamber) and compliance in the aorta (aortic column), and a loop which connects the blood pump to both the LV chamber (inlet) and the aortic column (outlet). The LV chamber has two one-way valves and a linear motor connected to a rolling seal, allowing it to generate pulsatile flow. The blood pump speed was tuned to achieve clinically relevant flow, based on the need to supplement a failing heart. The simulated heart rate (stroke rate of the linear actuator) cycled through 3 different settings each day to simulate changes in patient activity level. The sample size for the durability test was set to 18, and the test duration was 2 years. During the test, no critical blood pump failures were observed. There were no indications of significant decrease in pump performance or seal performance. Furthermore, no symptoms of failure, such as abnormal wear, were observed. In conclusion, the durability test successfully demonstrated that the EVAHEART Blood Pump achieved component reliability at a minimum of 90% reliability and 88% confidence interval over a mission life of two years.

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成人以上各年代の正常天然歯の咬頭嵌合位における咬合接触状態を明らかにするため三次元咬合検査法を用いて定量的に解析し,上顎臼歯について比較検討した.顎□腔系に自覚的、他覚的に機能障害を認めず,歯の欠損のない日本人健常有歯顎者20歳代(以下,Y-group),45〜54歳(以下,M-group),60歳以上(以下,E-group),各群5名の上顎臼歯を被検歯とした.咬みしめ強度を30%MVCに規定してシリコーンバイトを採得し,上下顎歯間距離60μm以下の領域を咬合接触域として解析を行った.また,第一,第二小臼歯の咬合面を頬側咬頭(以下,BC),舌側咬頭(以下,LC)近心辺縁隆線(以下,MMR),遠心辺縁隆線(以下,DMR)の4部位に分類し,第一,第二大臼歯の咬合面を近心頬側咬頭(以下,MBC),遠心頬側咬頭(以下,DEC),近心舌側咬頭(以下,MLC),遠心舌側咬頭(以下,DLC),近心辺縁隆線(以下,MMR),遠心辺縁隆線(以下,DMR),の6部位に分類し,それぞれの咬合接触域の傾斜方向を表現するため前頭面観における側方的な傾斜方向(Lateral angle)と矢状面観における前後的な傾斜方向(A/P angle)の2つのパラメータを用いた.
　第一小臼歯および第二小臼歯のLCにおいて3群すべてに100%の接触率で1点以上の接触点が認められ,接触面積ではY-groupとM-group,Y-groupとE-groupの間に有意な差が認められた.第一大臼歯のMLC,DLCおよび第二大臼歯のMLCにおいて3群すべてに100%の接触率で1点以上の接触点が認められ,接触面積ではY-groupとM-group. Y-groupとE-groupの間に有意な差が認められた.また,DBCの接触面積においてY-groupとM-groupの間に有意な差が認められた.さらに,これら有意差が認められた咬合面部位のLateral angle, A/P angleについて,5°ごとの咬合接触面積を統計学的検討したところ,咬合接触面積の変化が大きい傾斜角度が明らかになった.
　これらのことから,上顎臼歯の咬合面においてY-groupとM-groupとの間,Y-groupとE-groupとの間で,とくに機能咬頭における咬合接触状態の変化が大きいことが示された.

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