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Advanced driver-assistance systems such as Honda’s collision mitigation brake system (CMBS) can help achieve traffic safety. In this paper, the naturalistic driving study and a series of simulations are combined to better evaluate the performance of the CMBS in the Chinese traffic environment. First, because safety-critical situations can be diverse especially in the Chinese environment, the Chinese traffic-accident characteristics are analyzed according to accident statistics over the past 17 years. Next, 10 Chinese traffic-accident scenarios accounting for more than 80% of traffic accidents are selected. For each typical scenario, 353 representative cases are collected from the traffic-management department of Beijing. These real-world accident cases are then reconstructed by the traffic-accident-reconstruction software PC-Crash on the basis of accident-scene diagrams. This study also proposes a systematic analytical process for estimating the effectiveness of the technology using the co-simulation platform of PC-Crash and rateEFFECT, in which 176 simulations are analyzed in detail to assess the accident-avoidance performance of the CMBS. The overall collision-avoidance effectiveness reaches 82.4%, showing that the proposed approach is efficient for avoiding collisions, thereby enhancing traffic safety and improving traffic management.

Crash probability estimation is an important method to predict the potential reduction of crash probability contributed by forward collision avoidance technologies (FCATs). In this study, we propose a practical approach to estimate crash probability, which combines a field operational test and numerical simulations of a typical rear-end crash model. To consider driver hazard perception characteristics, we define a novel hazard perception measure, called as driver risk response time, by considering both time-to-collision (TTC) and driver braking response to impending collision risk in a near-crash scenario. Also, we establish a driving database under mixed Chinese traffic conditions based on a CMBS (Collision Mitigation Braking Systems)-equipped vehicle. Applying the crash probability estimation in this database, we estimate the potential decrease in crash probability owing to use of CMBS. A comparison of the results with CMBS on and off shows a 13.7% reduction of crash probability in a typical rear-end near-crash scenario with a one-second delay of driver's braking response. These results indicate that CMBS is positive in collision prevention, especially in the case of inattentive drivers or ole drivers. The proposed crash probability estimation offers a practical way for evaluating the safety benefits in the design and testing of FCATs.

This paper considers a comprehensive naturalistic driving experiment to collect driving data under potential threats on actual Chinese roads. Using acquired real-world naturalistic driving data, a near-crash database is built, which contains vehicle status, potential crash objects, driving environment and road types, weather condition, and driver information and actions. The aims of this study are summarized into two aspects: (1) to cluster different driving-risk levels involved in near-crashes, and (2) to unveil the factors that greatly influence the driving-risk level. A novel method to quantify the driving-risk level of a near-crash scenario is proposed by clustering the braking process characteristics, namely maximum deceleration, average deceleration, and percentage reduction in vehicle kinetic energy. A classification and regression tree (CART) is employed to unveil the relationship among driving risk, driver/vehicle characteristics, and road environment. The results indicate that the velocity when braking, triggering factors, potential object type, and potential crash type exerted the greatest influence on the driving-risk levels in near-crashes.

The (±)-tetrahydro-3-furylmethyl moiety, which is a characteristic part of the novel neonicotinoid dinotefuran, was found by research in which acetylcholine was selected as the lead compound. SAR (structure-activity relationships) for the tetrahydrofuran part indicated that the non-substituted moiety showed the highest level of activity, 4- and 5-substituted moieties showed intermediate levels, and 2- and 3-substituted moieties lost the activity. Conformational analysis of these compounds indicated that the substituents changed little the hypothetical active conformation of dinotefuran. Computational analysis proved that dinotefuran, a methoxypropyl compound and other neonicotinoids well overlapped, and dinotefuran adopts the active conformation more easily than the methoxypropyl compound. © Pesticide Science Society of Japan

Dinotefuran ((RS)-1-methyl-2-nitro-3-(tetrahydro-3-furylmethyl)guanidine) is a new neonicotinoid which has a characteristic (±)-tetrahydro-3-furylmethyl moiety instead of the pyridine-like moiety of other neonicotinoids. A series of dinotefuran derivatives were synthesized and tested against hemiptera. SAR (structure-activity relationships) of the nitroguanidine part of dinotefuran are summarized as follows: (1) the mono-methyl group as a N-substituent gave the best activity for the acyclic nitroimino and nitromethylene compounds, (2) the acyclic compounds showed the same activity as the cyclic compounds against Nephotettix cincticeps and were superior to them against Laodelphax striatellus, (3) N-acylation of this series scarcely changed the level of activity. On the basis of these results, we selected dinotefuran for development. © Pesticide Science Society of Japan

In addition to the real traffic accident data, naturalistic driving data can allow researchers gain insights into the factors that cause risk/hazard situations. This paper considers a comprehensive naturalistic driving experiment to collect detailed driving data on actual Chinese roads. Using acquired real-world driving data, a near-crash database is built, which contains vehicle status, potential crash object, driving environment and road type, and weather condition. K-means cluster analysis is applied to classify the near-crash cases into different driving risk levels using braking process features, namely maximum deceleration, average deceleration and percentage reduction in the vehicle kinetic energy. The results indicate that the velocity when braking and triggering factors have strong relationship with the driving risk level involved in near-crash cases.

エトフェンプロックスのエトキシ基を種々のハロメトキシ基に変換した類縁体を合成した. それらの化合物のハスモンヨトウやワモンゴキブリに対する殺虫活性は, エトフェンプロックスの活性と大差はなかった. ハルフェンプロックス (CF2BrO誘導体) のナミハダニに対する殺虫活性は著しく高く, エトフェンプロックスよりも約200倍強かった. これらの一連の化合物はエトフェンプロックスや従来のピレスロイドと同じく, ワモンゴキブリの中枢神経に反復興奮を誘導し, ザリガニの巨大神経軸索膜にナトリウム性テイル電流を誘導した. ハルフェンプロックスの強い殺ダニ活性には, 神経活性の強さのほかにベンゼン環置換基の疎水性が深く関係しているように見受けられた.

Japan has a higher rate of rear-end collisions than any other kind of traffic accident and the causes of rear-end collisions were investigated. Accident statistics were used to conduct a statistical traffic accident analysis while a questionnaire was used to conduct a detailed traffic accident analysis and simulation was then used to perform traffic accident analysis. The results of the traffic accident analysis suggested that many of these accidents were caused by lack of attention during daily driving. Research was conducted to determine what kind of collision avoidance systems would be effective. A system was developed that is effective in reducing the collision velocity during rear-end collisions by making up for driver delays in recognition, judgment and operation by means of brake control and external sensing technology using millmeter wave radar sensor. This paper will discuss the testing and development of this new system.