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As a significant active safety technology towards fully autonomous driving, driver-automation co-piloting provides a new thinking for enhancing vehicle active safety and relieving driver's workload. However, the preview pattern divergence between driver and steering assistance system (SAS) may give rise to serious steering conflicts, which reduces driver's faith in SAS, cause him/her to turn off it, and even result in fatal traffic accidents. Focusing on mimicking the driver's steering behaviour, this paper proposes a human-like steering assistance scheme by adaptively varying the preview time and assistance gain of the SAS controller. Driver's preview behaviour of the road curvature is numerically identified using simulator tests along a multi-curves road, based on which a nominal preview-scheduled driver model is established. Based on the nominal driver model, a co-piloting system featuring human-like preview behaviour and a time-varying assistance penalty is proposed to formulate the steering torque-overlay dynamics of both agents in path-tracking. Next, a linear parameter varying (LPV)/H∞ controller satisfying pole placement is integrated to ensure the robustness and stability within the entire parameter space. This enables the steering assistance scheme to have a scheduled preview pattern like a human driver. Results of driving simulator experiment indicate that the proposed steering assistance scheme is able to mitigate driver-SAS conflicts and improve driver's path-tracking performance. [ABSTRACT FROM AUTHOR]

This paper is concerned with developing a new method for measuring a driver’s steering efficiency during a steering manoeuvre, for investigating the driver’s steering performance and for evaluating the steering comfort. Electromyography was successfully used to measure the driver’s muscle activity and to reveal the function of the driver’s key muscles in the steering manoeuvre. A measurement of the driver’s steering efficiency during a dynamic steering manoeuvre with two hands is presented on the basis of a regression analysis of the electromyography and steering-force data. The proposed measurement procedure consists of two parts. First, a multiple-regression analysis of the steering-force and electromyography data is conducted, and the steering forces in the steering wheel plane are predicted using the electromyography data of the key muscles producing the steering torque. Second, by predicting the steering force, the force capacity of the driver in the steering manoeuvre is estimated, and then the steering efficiency of the driver is measured. The steering efficiency of the driver, which characterizes the inefficiency, is thought to be a significant movement control strategy employed by driver, and its application in investigating the driver’s steering strategy is the subject of further study. [ABSTRACT FROM PUBLISHER]

A steer-by-wire system, which has no mechanical constraints between steering wheel and front wheel, is expected to improve steering performance. The mechanical resistance torque is not transmitted from the front wheel to the steering wheel, and it is essential to simulate the torque around the steering wheel for better human-machine interface. Previous studies investigated resistance torque control originating from vehicle behaviour variables such as yaw rate and lateral acceleration. However, other variables such as steering wheel angle and front wheel actuation force are also good candidate sources to generate resistance torque. In this paper, first, four general guidelines are introduced to evaluate three types of resistance torques, i.e., the steering wheel angle origin, the steering force origin and the vehicle behaviour origin. First two guidelines are for 'driver-made' phase to make a turn, while the third guideline is for 'vehicle-made' phase to return to straight driving and the fourth one is the applicability guideline. Satisfaction of these guidelines by each of the three resistance torques is examined by the actual vehicle experiment. A necessity of combining these three types of resistance torques is indicated as a future subject. [ABSTRACT FROM AUTHOR]

It was reported that Steer-By-Wire (SBW) system, which eliminates driver interference, could introduce the active front steering control easier than that with a conventional steering system. But there have been few reports on studies about reactive torque control strategy for the steering wheel. This research on reactive torque control strategy was carried out in order to improve the driver usability and maneouvrability of SBW system. It was found that the relation between what drivers feel by reactive torque when turning the steering wheel and what they feel from vehicle behaviour could be improved by means of applying newly developed reactive torque that incorporates vehicle dynamics by means of applying newly developed reactive torque reactive that incorporates vehicle dynamics parameter. [ABSTRACT FROM AUTHOR]

Steering reaction torque is one important piece of information for drivers since it has significant influence on the maneuverability of the vehicle. Even with today's advanced simulation technology, however, it is very difficult to simulate factors such as accurate steering feeling. The purpose of this study is to develop a steering Hardware-in-the-Loop (HIL) simulator that can quantitatively evaluate steering systems. The validity of this HIL simulator has been ascertained by comparing the simulation results with those obtained during actual vehicle testing. A qualitative evaluation of the influences to reflect results on the design of the system performance is also reported. [ABSTRACT FROM AUTHOR]

A 60s male was admitted to our hospital for a diagnosis of gastric tumor sized 20 mm in diameter at the fornix of the stomach. Endoscopic mucosal resection (EMR) was performed, and the resected tumor was pap, m, ly0, v0, HMX, VM0, pathologically. One month after the EMR, the local recurrence was confirmed and a partial gastrectomy was performed. Pathological findings were tub1, sm2, ly1, v1, HM0, VM0. Total gastrectomy was added because of the possibility of the lymph node metastasis. Pathological findings revealed no residual cancers. The final pathological diagnosis was T1b(sm2) N0H0P0M0, Stage IA, based on the Japanese classification of gastric cancer. Three months thereafter, CT showed multiple liver metastases. Immunohistochemical study of the operated tumor revealed AFP-producing gastric cancer. Chemotherapy was performed, but he died of the gastric cancer. Endoscopic treatment is a minimally invasive therapeutic strategy, but it requires a considerable care in application.

We report two cases of neuroendocrine carcinoma of the rectum. CASE 1: A 50s woman was diagnosed as rectal cancer and underwent anterior resection of the rectum and lymphnode dissection. The histological diagnosis was neuroendocrine carcinoma with peritoneal dissemination. She was treated with chemotherapy as an outpatient. One year later from the operation, multiple liver metastases were revealed and she died eight months later. CASE 2: A 50s man underwent endoscopic mucosal resection (EMR) of the rectum as rectal tumor and histological diagnosis was an early well-moderate deferenciated carcinoma and its cut-tend was unclear. He received a careful follow-up. One year later, a follow-up colonoscopy revealed a submucosal tumor in the lower rectum. He was diagnosised with local reccurence of rectal cancer, and then underwent an abdominoperineal resection of the rectum and lymphnode dissection. The histological diagnosis was poorly differenciated neuroendocrine carcinoma with lymphnode metastasis. Two months later from the operation, a local reccurence was revealed and he was treated with octreotide and irradiation.

We report a case of gastric metastasis of lung cancer performed gastrectomy for the primary foci. A 70s woman was diagnosed as having right lung cancer and underwent right lower lobectomy and lymph node dissection. The histological diagnosis was adenocarcinoma (pT4, N2, M0). Four years later, positron emission tomography (PET)-CT revealed a tumor in the stomach and para-aortic lymph nodes swelling. The submucosal tumor was showed in the cardia by endoscopic examination. Biopsy showed a papillary adenocarcinoma. With the diagnosis of gastric metastasis from lung cancer, she was operated on. A proximal gastrectomy was carried out. The histopathological examination demonstrated papillary adenocarcinoma similar to that of the lung cancer with lymph node metastasis. No postoperative complications occurred and she was discharged from the hospital. Since then, she was treated with adjuvant chemotherapy as an outpatient.

We report a case of multiple liver metastases of rectsigmoid colon cancer treated with systemic chemotherapy and hepatectomy. A 40s woman had undergone anterior resection of rectum for rectsigmoid colon cancer with multiple liver metastases. Then FOLFOX4 regimen was performed fifteen times, and FOLFIRI regimen was performed eleven times. After chemotherapy was enforced, an abdominal CT revealed that liver metastases were reduced in size (effect judgment of partial response). Hepatic resection of the right lobe and partial of S2 segment were performed. Pathological findings of the resected liver revealed no residual cancer cells, indicating that the histological effect of chemotherapy was complete response (CR).

Unlabelled: The expandable metallic stent (EMS) have been used to treat obstructive colorectal cancer. We used EMS in 13 out of 14 cases of obstructive colorectal carcinoma patients (insertion rate 93%). Of these 13 cases, 6 cases were male patients, and 7 cases were female patients. The average age was 69.1-years-old (44-87). The placement of insertion part in rectum and sigmoid colon was 8 cases and 5 cases, respectively. We detained Ultraflex non-covered type for all patients. Seven patients were able to have an operation after stenting. After the stent treatment, 11 patients were able to eat, and 7 patients were discharged from hospital., Complications: perforation and stent migration were occurred in one case. These results suggested that EMS might be an effective treatment for obstructive colorectal carcinoma.