Field Scene Recognition for Navigating Autonomous Agricultural Vehicle

( Yoshinari Morio ),( Yuta Sawada ),( Masataka Shioji ),( Motoki Tanaka ),( Katsusuke Murakami ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

In this study, four agricultural vehicle navigation systems, namely, two different types of vehicle position estimation systems for self-localization of an autonomous agricultural vehicle, an obstacle detection system for safety self-driving, and an agricultural key-objects recognition system for intelligent worker assistance, were developed by using image processing system without using GNSS and LiDAR. Firstly, in the two types of vehicle position estimation systems, the position of a vehicle could be estimated by matching an input field scene image to the training scene images captured along each of targeted traveling routes. The scene images were captured by using a three-camera-type of capture system with left camera, front camera, and right camera. Secondly, in the obstacle detection system, obstacles on a road, ditches along a road, and the level difference between a traveling road and a farm field were detected by using the stereo camera built with two web camera. The obstacles, ditches, and the level difference were recognized by in real time estimating 3D ground plane. Finally, in the agricultural key-objects recognition system, key-object types(workers, trucks, containers, agricultural machines) and key-posture types(standing, squat, stoop, sitting), key-worker-direction types (front, back, left, right), and container contents amount could be recognized by using deep learning based system of YOLO. The experimental results demonstrated the potential of our systems for navigating an autonomous vehicle in agricultural fields.

Influence of Atomizing Condition on Particle Size Distributions for High Pressure Water Atomized Powder

Nakabayashi Koei,Tanaka Yoshinari,Hirai Masazumi 한국분말야금학회 2006 한국분말야금학회 학술대회논문집 Vol.2006 No.1

To improve the properties of fine metal powder, such as particle size distribution and geometric standard deviation, this work was done at various atomizing conditions. The new atomization mechanism and the correlation equation were proposed to estimate the mean particle diameter.

Different tolerance of zooplankton communities to insecticide application depending on the species composition

Sakamoto, Masaki,Tanaka, Yoshinari The Ecological Society of Korea 2013 Journal of Ecology and Environment Vol.36 No.2

Natural zooplankton communities are composed of many different species at different trophic levels in the aquatic food web. Several researchers have reported that in mesocosm/enclosure experiments, larger cladocerans tend to be more sensitive to carbamate insecticides than smaller ones (Daphnia > Moina, Diaphanosoma > Bosmina). In contrast, results from individual-level laboratory tests have suggested that large cladoceran species are more tolerant than small species. To clarify this inconsistency, we conducted a microcosm experiment using model zooplankton communities with different species compositions, where animals were exposed to lethal (near to the 24 h LC50, concentration estimated to kill 50% of individuals within 24-h for the small cladoceran Bosmina) and lower, sublethal concentrations of carbaryl. In the experiment, population densities of the small cladocerans (Bosmina and Bosminopsis) decreased subsequent to the applications of chemical, but no impacts were observed on the large cladoceran Daphnia. Our results supported the reports of previous individual level toxicity tests, and indicated that the sensitivity of zooplankton to the insecticide was unchanged by biological interactions but the response of population can be modified by compensation of population through hatching from resting eggs and/or the persistence of insecticide in the systems.

Different tolerance of zooplankton communities to insecticide application depending on the species composition.

Masaki Sakamoto,Yoshinari Tanaka 한국생태학회 2013 Journal of Ecology and Environment Vol.36 No.2

Natural zooplankton communities are composed of many different species at different trophic levels in the aquatic food web. Several researchers have reported that in mesocosm/enclosure experiments, larger cladocerans tend to be more sensitive to carbamate insecticides than smaller ones (Daphnia > Moina, Diaphanosoma > Bosmina). In contrast, results from individual-level laboratory tests have suggested that large cladoceran species are more tolerant than small species. To clarify this inconsistency, we conducted a microcosm experiment using model zooplankton communities with different species compositions, where animals were exposed to lethal (near to the 24 h LC50, concentration estimated to kill 50% of individuals within 24-h for the small cladoceran Bosmina) and lower, sublethal concentrations of carbaryl. In the experiment, population densities of the small cladocerans (Bosmina and Bosminopsis) decreased subsequent to the applications of chemical, but no impacts were observed on the large cladoceran Daphnia. Our results supported the reports of previous individual level toxicity tests, and indicated that the sensitivity of zooplankton to the insecticide was unchanged by biological interactions but the response of population can be modified by compensation of population through hatching from resting eggs and/or the persistence of insecticide in the systems.

Association between Lymphovascular Invasion and Recurrence in Patients with pT1N+ or pT2–3N0 Gastric Cancer: a Multi-institutional Dataset Analysis

Keizo Fujita,Mitsuro Kanda,Seiji Ito,Yoshinari Mochizuki,Hitoshi Teramoto,Kiyoshi Ishigure,Toshifumi Murai,Takahiro Asada,Akiharu Ishiyama,Hidenobu Matsushita,Chie Tanaka,Daisuke Kobayashi,Michitaka F 대한위암학회 2020 Journal of gastric cancer Vol. No.

Purpose: Patients with pathological stage T1N+ or T2–3N0 gastric cancer may experience disease recurrence following curative gastrectomy. However, the current Japanese Gastric Cancer Treatment Guidelines do not recommend postoperative adjuvant chemotherapy for such patients. This study aimed to identify the prognostic factors for patients with pT1N+ or pT2–3N0 gastric cancer using a multi-institutional dataset. Materials and Methods: We retrospectively analyzed the data obtained from 401 patients with pT1N+ or pT2–3N0 gastric cancer who underwent curative gastrectomy at 9 institutions between 2010 and 2014. Results: Of the 401 patients assessed, 24 (6.0%) experienced postoperative disease recurrence. Multivariate analysis revealed that age ≥70 years (hazard ratio [HR], 2.62; 95% confidence interval [CI], 1.09–7.23; P=0.030) and lymphatic and/or venous invasion (lymphovascular invasion (LVI): HR, 7.88; 95% CI, 1.66–140.9; P=0.005) were independent prognostic factors for poor recurrence-free survival. There was no significant association between LVI and the site of initial recurrence. Conclusions: LVI is an indicator of poor prognosis in patients with pT1N+ or pT2–3N0 gastric cancer.

Association between Lymphovascular Invasion and Recurrence in Patients with pT1N+ or pT2-3N0 Gastric Cancer: a Multi-institutional Dataset Analysis

Fujita, Keizo,Kanda, Mitsuro,Ito, Seiji,Mochizuki, Yoshinari,Teramoto, Hitoshi,Ishigure, Kiyoshi,Murai, Toshifumi,Asada, Takahiro,Ishiyama, Akiharu,Matsushita, Hidenobu,Tanaka, Chie,Kobayashi, Daisuke The Korean Gastric Cancer Association 2020 Journal of gastric cancer Vol. No.

Purpose: Patients with pathological stage T1N+ or T2-3N0 gastric cancer may experience disease recurrence following curative gastrectomy. However, the current Japanese Gastric Cancer Treatment Guidelines do not recommend postoperative adjuvant chemotherapy for such patients. This study aimed to identify the prognostic factors for patients with pT1N+ or pT2-3N0 gastric cancer using a multi-institutional dataset. Materials and Methods: We retrospectively analyzed the data obtained from 401 patients with pT1N+ or pT2-3N0 gastric cancer who underwent curative gastrectomy at 9 institutions between 2010 and 2014. Results: Of the 401 patients assessed, 24 (6.0%) experienced postoperative disease recurrence. Multivariate analysis revealed that age ≥70 years (hazard ratio [HR], 2.62; 95% confidence interval [CI], 1.09-7.23; P=0.030) and lymphatic and/or venous invasion (lymphovascular invasion (LVI): HR, 7.88; 95% CI, 1.66-140.9; P=0.005) were independent prognostic factors for poor recurrence-free survival. There was no significant association between LVI and the site of initial recurrence. Conclusions: LVI is an indicator of poor prognosis in patients with pT1N+ or pT2-3N0 gastric cancer.