In this study, we propose the particle swarm optimization (PSO) algorithm, a new method to dynamically adapt the PSO population size. PSO (SG-PSO) takes advantage of the fact that in practical problems there is a limit to the required accuracy of the optimization result. In SG-PSO, particles are stopped when they have approximately reached the required accuracy. Stopped particles do not consume valuable function evaluations. Still, the information contained in the stopped particles' state is not lost, but rather as the swarm evolves, the particles may become active again, behaving as a memory for the swarm. In addition, as an extension to the SG-PSO algorithm we propose the mixed SG-PSO (MSG-PSO) algorithm. In the MSG-PSO algorithm each particle is given a required accuracy, and through the accuracy settings global search and local search can be balanced. Both SG-PSO and MSG-PSO algorithms are straightforward modifications to the standard PSO algorithm. The SG-PSO algorithm shows strong improvements over the standard PSO algorithm on multimodal benchmark functions from the PSO literature while approximately equivalent results are observed on unimodal benchmark functions. The MSG-PSO algorithm outperforms the standard PSO algorithm on both unimodal and multimodal benchmark functions.

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In this study, we propose the particle swarm optimization (PSO) algorithm, a new method to dynamically adapt the PSO population size. PSO (SG-PSO) takes advantage of the fact that in practical problems there is a limit to the required accuracy of the optimization result. In SG-PSO, particles are stopped when they have approximately reached the required accuracy. Stopped particles do not consume valuable function evaluations. Still, the information contained in the stopped particles' state is not lost, but rather as the swarm evolves, the particles may become active again, behaving as a memory for the swarm. In addition, as an extension to the SG-PSO algorithm we propose the mixed SG-PSO (MSG-PSO) algorithm. In the MSG-PSO algorithm each particle is given a required accuracy, and through the accuracy settings global search and local search can be balanced. Both SG-PSO and MSG-PSO algorithms are straightforward modifications to the standard PSO algorithm. The SG-PSO algorithm shows strong improvements over the standard PSO algorithm on multimodal benchmark functions from the PSO literature while approximately equivalent results are observed on unimodal benchmark functions. The MSG-PSO algorithm outperforms the standard PSO algorithm on both unimodal and multimodal benchmark functions.

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This paper investigates characteristics of the -- traffic wave that occurs frequently in congested traffic, and describes its development and evolution in time and space. Using NGSIM trajectory dataset, we investigated the relationship between the development of -- waves and lane changing events which causes deceleration of vehicles and subsequent wave growth and dissipation. Asymmetric traffic theory assuming the separation between acceleration and deceleration behavior was used as a framework for interpretation and explanation of the observed results. And, reciprocal interactions between consecutive -- waves were studied. Finally, we concluded that the characteristics of -- waves are closely related to asymmetric driving behavior.

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It is widely known that the composition of blowby and crankcase gases plays an important role in the formation of low-temperature sludge in engine oil. It is further known that NO_x reacts with olefin contents of unburned gasoline to form sludge precursors. It is acknowledged that engine operation during -- driving accelerates sludge formation. In this study, the authors developed an oil evaluation test which combines the -- driving elements into a single STOP/GO driving mode and investigated why -- driving accelerates sludge formation. It was found that in low-temperature engine operation in the stop element of the STOP/GO driving mode, NO_x and unburned gasoline are absorbed into the oil, and in high-temperature operation in the go element of the STOP/GO driving mode, NO_x and unburned gasoline are released from the oil. NO_x comes in contact with unburned gasoline in the combustion chamber during the compression stroke and in the vapor of the crankcase ; it reacts with olefins in the unburned gasoline to form sludge.

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Traffic congestion is usually observed at the upper stream of bottlenecks such as tunnels. Congestion appears as -- waves and high-density uniform flow. We perform simulations of traffic flow with a bottleneck using the coupled map optimal velocity model. The bottleneck is expressed as a road segment with speed reduction. The speed reduction in the bottleneck controls the emergence of -- waves. A phenomenological theory of bottleneck effects is constructed.

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The preparation and application of a extraction tip (StageTip) used for pre-purification of sample solutions for LC-MS/MS analysis of DNA adducts was simplified and improved to increase throughput while maintaining high adduct selectivity. It was demonstrated that the StageTip composed of two sheets of a poly(styrene-divinylbenzene) copolymer disk could be easily prepared and proved useful for selective extraction of trace amounts of DNA adducts from a sample solution containing a great quantity of normal deoxynucleosides.

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A 69-year-old man with post-operative recurrence of lung adenocarcinoma was treated with multiple chemotherapies, including epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors. A second biopsy revealed an EGFR T790M mutation. As 10th-line chemotherapy, osimertinib was initiated. After 24 weeks, chest computed tomography (CT) revealed asymptomatic ground-glass opacities in both lobes. After four weeks of osimertinib discontinuation, imaging revealed rapid lung cancer progression. Osimertinib was resumed. After 11 weeks, CT revealed decreased lung nodules with no exacerbation of interstitial lung disease. We describe a patient who experienced transient asymptomatic pulmonary opacities during treatment with osimertinib, which was successfully managed by a "

--" approach.

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The effects of a localized perturbation in an initially uniform traffic flow are investigated with the optimal velocity model under an open boundary condition. The parameter region where the uniform solution is convectively unstable is determined by linear analysis. It is shown that the oscillatory flow, which is linearly unstable but convectively stabilized, is triggered out of a linearly unstable uniform flow by a localized perturbation, and in the upper stream it eventually breaks up into an alternating sequence of jams and free flows. This observation suggests that the real traffic flow pattern observed near an on-ramp [B. S. Kerner: Phys. Rev. Lett. 81 (1998) 3797] is a noise-sustained structure in an open flow system. We also find that, in a certain parameter region, the convectively stabilized uniform flow is destabilized by the non-linearly induced free flow.

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Obstacle avoidance is currently treated by methods that fall into two broad categories, global and local. In this paper, we consider the case that the environment contains obstacles whose speed and direction cannot be predicted. To avoid such kind of obstacles, we introduce a local path planning methodology for a robotics by using Cellular Automata model. This local path planning was combined with Dijkstra shortest path algorithm as global path planning to obtain an optimal route. Using the proposed methodology, a scene in a typical hospital corridor has been created. By using CA model, we evaluated two kinds of obstacle avoidance movement. First, the robotic use the " " method, which is the robotic will decrease its speed while encounter a transient obstacle. The second one is detour model, in which the robotic will make a detour motion to avoid a transient obstacle. The simulation results show that in dynamic environment that having transient obstacles, the " " method produced minimal collision with shortest-distance path. While, using the detour model generated minimal collision with time-minimal navigation path.

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The car-following platoon consisted of ten vehicles with the leading vehicle initiating perturbations on a test-track. Vehicle movements varied based on the speed patterns initiated by the leading vehicle with each data set including a cycle of stop, acceleration, car-following, deceleration, and complete stop. Shock waves are normally used for conditions at a fixed location, however this study focused on observing repeated shock waves created by the same group of drivers repeatedly. As well as studying the vehicle trajectories in microscopic level, speed wave propagations among the vehicles were also studied considering asymptotic stability in the car-following platoon. After carefully reviewing the vehicle trajectories, it was found that there is a discrepancy between actual vehicle trajectories and hypothetical uniform traffic flows in the shock wave theory derived from the macroscopic traffic model especially in the case of short distances.

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 A pedestrian simulation is one of effective means to verify the size of space and share the information of a crowd safety measure in an urban area that a large number of unspecified people visit. This study aims to reproduce pedestrian movements in high density queues and to clarify a mechanism of lane formation in contra-flow by using a multi-agent system. The crowd flow is based on the social force model, which is said that crowd dynamics at a state of emergency can be reproduced. To apply this model to pedestrian movements in a high density queue at ordinary times, we add new functions, which are ellipse-based collision detection and following behavior after an agent ahead. The following behavior includes the parameters to control propagation speed of -- waves in a queue. To confirm the reproducibility, we compare observation data of pedestrian movements in queues at urban facilities. In addition, we simulate a contra-flow and the lane formation phenomena to analyze the influence of the following behavior on crowd dynamics. The results are as follows.
 If the shape of an agent is a circle of the radius 30 cm, the collision between agents is detected at the line density of 1.67 people per meter. On the other hand, the system represents a pedestrian movement having the line density of 2.1 people per meter by making the shape of an agent an ellipse 30 cm in the major axis and 15 cm in the minor axis. In addition, by dynamic control of the parameter values (a, b) involving the fundamental diagram for pedestrians, and the parameter values (C_i, D_i) involving line density during standing and walking, it is possible to reproduce the characteristic values of observation data, which are line density, propagation speed of -- waves. If the static parameter values are set, it is hard to agree with propagation speed of several -- waves accurately. However, it is useful to predict the characteristics of pedestrian movements in a queue. As a result of an application to contra-flows by using the multi-agent system, the lanes are formed regardless of the following behavior when the crowd density is low. On the other hand, the following behavior facilitates lane formation in the contra-flow with a density of over 1.0 people per square meter. It is an important point to enhance crowd safety. From the above results, we developed the general-purpose multi-agent system which enables to reproduce pedestrian movements in a queue and lane formation of contra-flow by extending an existing crowd dynamics model at a state of emergency.

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To understand human motor control, we constructed a virtual inverted pendulum (VIP) on a computer display. Subjects moved a computer mouse to stand the pendulum. The previous work showed that movements were repetition of "" "", and maximal velocities during the "go" phase seemed proportional to that of the pendulum's top in the preceding "stop" phase. The present study examined effects of velocities of the pendulum's top on VIP control.

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本論文は, 一般道路の一時停止を伴う合流部における走行支援情報提供サービスの意義や可能性を, 実験を通じて把握することを目的としている. はじめに, 当該合流部におけるサービスの意義とその方法論について考察を行った. 次に, 実交通環境下で模擬システムによる走行実験を簡易に行う方法を考案し, 国道246号線青葉台ランプにおいて情報提供の効果を分析した. その結果, 限定的ではあるが, ドライバーの流入判断と極めて近い判断を与えるような情報が判断時間を短くする可能性があること, “止まれ” の情報は全体としては合流判断を安定させるが, 条件によっては混乱を生じる可能性があること, 情報提供により合流部における危険な合流の可能性を小さくすることを確認した.

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【緒言】わが国でのメサドンの使用は, 先行する強オピオイドからの変更に限られており, 先行オピオイドを中止してメサドンを開始する－－ (SAG)法が推奨されている. 【症例】悪性腸腰筋症侯群による難治性疼痛に対し, モルヒネとケタミンの併用からメサドンにSAG法で変更した. 一時的に疼痛が増強したが, モルヒネの再開と約2週間の併用によって疼痛緩和を得た. 【考察】本症例のように疼痛コントロールが不良でメサドンに変更する場合には, 段階的に置き換える方法がSAG法よりも有用であると考える. メサドンは, 過量投与の問題を考慮して少なめに開始するのが安全であり, 疼痛の増強を回避するためには, より柔軟な初回投与量の設定や用量調節の検討が必要と考える. 併用している鎮痛補助薬をメサドンへの変更時に継続する妥当性, 特にNMDA受容体拮抗作用がメサドンと重複するケタミンを継続することの妥当性については, 今後も議論を深める必要がある.

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Applying image sensors to modern vehicle control systems effectively reduces the driver's workload and improves safety, comfort and driving pleasure. A lane-keeping support system and an adaptive cruise control (ACC) system with -- capability commercialized by Nissan Motor Co., Ltd. in 2001 are described as examples of applications of such sensors in mtelligent automobiles. The dynamic range required of an image sensor for intelligent automotive applications is discussed. Other characteristics required for future applications are also mentioned.

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Respiratory gated VMAT (volumetric modulated arc therapy) repeats rapid

operations of a MLC (multileaf collimator) by turning the beam on and off by respiratory gating. The rapid operations of the MLC during respiratory gated irradiation may induce position error of the MLC and may affect output error and dose distribution. The purpose of this study was to clarify the relationship between the MLC position accuracy of the respiratory gated VMAT and the VMAT parameters. In the method, 1 arc, 2 arcs, and 4 arcs plan were created for the virtual target and irradiation was performed without the gated respiration and with the gated respiration. The respiratory gated system used a RPM (real-time position management system). The MLC position error, gap size error, and the MLC leaf speed were calculated from a log-file. In the histogram of the gap size error, the frequency of falling within the error range up to 0.2 mm was about 12 percentage points higher for the gated respiration. The MLC position error increased with increasing the MLC leaf speed. The correlation coefficient between the MLC leaf speed and the MLC position error exceeded 0.96, showing a strong correlation. Dose rate of VMAT parameters decreased with increasing arc number with the gated respiration and without the gated respiration. Gated irradiation was temporarily stopped, and it decreased by about 27% with respect to the dose rate without the gated respiration. The gantry rotation speed repeated the stop and re-rotation operations when gated irradiation was performed. For all arcs, the rotation speed decreased by about 30% compared with the rotation speed without the gated respiration. The pass rate of gamma analysis for each arc plan was about 95%. No effect on gated irradiation dose distribution was observed. Respiratory gated irradiation reduced dose rate change and gantry rotation speed of the VMAT. Reduction of the MLC leaf speed occurred, and the MLC position error and gap size error decreased. The MLC positional accuracy was secured, and it was confirmed that there was no effect on dose distribution by the respiratory gated VMAT.

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本論文は, 一時停止を伴う合流部におけるギャップ選択の局面を対象に, 判断の変動に与える要因について実証的に分析を行うことを目的としている. 始めに, ドライバーのギャップに対する判断プロセスを4つの時間パラメータを導入してモデル化を行い, 時間パラメータの変動要因と交通安全対策との対応関係を考察した. モデルの妥当性検証のために, プローブカーを利用したギャップ選択実験と情報提供実験を実施し, 得られたデータを用いて時間パラメータの変動に与える要因を分散分析により抽出した.

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Because the ionization efficiency for glycopeptides is lower than that of peptides in electrospray ionization, it is frequently necessary to enrich them prior to their analysis using liquid chromatography coupled with tandem mass spectrometry. Although some methods for selectively enriching glycopeptides (e.g., lectin, agarose, and cellulose methods) have been reported, they are time-consuming (procedures that require several hours) and may not be applicable to submicrogram-sized samples. Here, we report on a rapid, simple method for enriching glycopeptides in small sample amounts using cellulose hydrophilic interaction (cellulose HILIC)/reversed-phase (RP)

-- extraction tips (StageTips). Using the cellulose HILIC/RP StageTips, glycopeptide-selective enrichment can be achieved at the nanogram level within a few minutes.

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