Development of an automated guidance system for rice transplanter1

( Fang-ming Zhang ),( Xi-ming Feng ),( Yuan Li ),( Beom-soo Shin ),( Ru-jiang Shou ) 한국농업기계학회 2012 한국농업기계학회 학술발표논문집 Vol.17 No.1

An automated guidance system was developed on a rice transplanter. A distributed embedded computer system, one ECC and 5 ECUs, was constructed. Two Kalman filters were formed. The 1^st one, named as global Kalman filter, integrated data of a RTK-GPS, a strapdown attitude sensor, and two encoders. The 2^nd one, named as local Kalman filter, integrated data of a strapdown attitude sensor and two encoders. A PID controller was applied to row following control, whose offset RMS could less than 4 cm at speed of 1.2 m/s. A U-turn controller was also designed that it could control the transplanter in a go-turn-back mode.

Development of a Prototype of Guidance System for Rice-transplanter

Zhang, Fang-Ming,Shin, Beom-Soo,Feng, Xi-Ming,Li, Yuan,Shou, Ru-Jiang Korean Society for Agricultural Machinery 2013 바이오시스템공학 Vol.38 No.4

Purpose: It is not easy to drive a rice-transplanter avoiding underlapped or overlapped transplanting in paddy fields. An automated guidance system for the riding-type rice-transplanter would be necessary to operate the rice-transplanter autonomously or to assist the beginning drivers as a driving aid. Methods: A prototype of guidance system was composed of embedded computers, RTK-GPS, and a power-steering mechanism. Two Kalman filters were adopted to overcome sparse positioning data (1 Hz) from the RTK-GPS. A global Kalman filter estimated the posture of rice-transplanter every one second, and a local Kalman filter calculated the posture from every new estimation of the global Kalman filter with an interval of 200 ms. A PID controller was applied to the row-following mode control. A control method of U-turning mode was developed as well. A stepping motor with a reduction gear set was used to rotate the shaft of steering wheel. Results: Test trials for U-turning and row-following modes were done in a paddy field after some parameters have been tuned at the ground speed range of 0.3 ~ 1.2 m/s. The minimum RMS error of offset was 3.13 cm at the ground speed of 0.3 m/s while the maximum RMS error was 13.01 cm at 1.2 m/s. The offset RMS error tended to increase as the ground speed increased. The target point distance, LT also affected the system performance and PID controller parameters should be adjusted on different ground speeds. Conclusions: A target angle-based PID controller plus stationary steering angle controller made it possible for the rice-transplanter to steer autonomously by following a reference line accurately and even on U-turning mode. However, as condition in paddy fields is very complicated, the system should control the ground speed that prevents it from deviating too much due to ditch and slope.

Off-Road Machinery Systms Engineering : Development of a Prototype of Guidance System for Rice-transplanter

( Fang Ming Zhang ),( Beom Soo Shin ),( Xi Ming Feng ),( Yuan Li ),( Ri Jiang Shou ) 한국농업기계학회 2013 바이오시스템공학 Vol.38 No.4

Purpose: It is not easy to drive a rice-transplanter avoiding underlapped or overlapped transplanting in paddy fields. An automated guidance system for the riding-type rice-transplanter would be necessary to operate the rice-transplanter autonomously or to assist the beginning drivers as a driving aid. Methods: A prototype of guidance system was composed of embedded computers, RTK-GPS, and a power-steering mechanism. Two Kalman filters were adopted to overcome sparse positioning data (1 Hz) from the RTK-GPS. A global Kalman filter estimated the posture of rice-transplanter every one second, and a local Kalman filter calculated the posture from every new estimation of the global Kalman filter with an interval of 200 ms. A PID controller was applied to the row-following mode control. A control method of U-turning mode was developed as well. A stepping motor with a reduction gear set was used to rotate the shaft of steering wheel. Results:Test trials for U-turning and row-following modes were done in a paddy field after some parameters have been tuned at the ground speed range of 0.3 ~ 1.2 m/s. The minimum RMS error of offset was 3.13 cm at the ground speed of 0.3 m/s while the maximum RMS error was 13.01 cm at 1.2 m/s. The offset RMS error tended to increase as the ground speed increased. The target point distance, LT also affected the system performance and PID controller parameters should be adjusted on different ground speeds. Conclusions: A target angle-based PID controller plus stationary steering angle controller made it possible for the rice-transplanter to steer autonomously by following a reference line accurately and even on U-turning mode. However, as condition in paddy fields is very complicated, the system should control the ground speed that prevents it from deviating too much due to ditch and slope.

Time Trends of Ovarian Cancer Incidence in China

Wang, Bing,Liu, Shu-Zheng,Zheng, Rong-Shou,Zhang, Fang,Chen, Wan-Qing,Sun, Xi-Bin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

The aim of this study was to examine the trend of ovary cancer incidence from 1999 to 2010 in China and predict the burden up to 2020. Crude incidence, age specific incidence and age-adjusted incidence rates were calculated. Joinpoint regression was performed to obtain estimated annual percentages and Bayesian age-period-cohort modeling was used to predict the incidence rate until the year 2020. In China, the crude rate of ovary cancer was 7.91/100,000 and the age-adjusted rate was 5.35/100,000 overall during period 1999-2010. The rates in urban regions were higher than in rural regions. A significant rising trend during 1999-2006 was followed by a drop during 2006-2010 in age-adjusted rates for urban females. In contrast, constant rise was observed in rural women. The decrease in ovary cancer of urban areas tended to be restricted to women aged 50 years and younger. In contrast, increases of ovary cancer in rural areas appeared in virtually all age groups. Although the age-adjusted incidence rate for ovary cancer was predicted to be reduced after year 2011, the crude rate was likely to be relative stable up to 2020. The burden of ovary cancer in China will continue to be relative stable due to the aging population.

Methionine Synthase Reductase A66G Polymorphism is not Associated with Breast Cancer Susceptibility - a Meta-analysis

Hu, Shu,Liu, Hong-Chao,Xi, Shou-Ming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.7

Background: Several studies have investigated the association between methionine synthase reductase (MTRR) A66G polymorphism and breast cancer risk, but controversial results were yielded. Therefore, we performed a meta-analysis to provide a more robust estimate of the effect of this polymorphism on susceptibility to breast cancer. Materials and Methods:Case-control studies investigating the relationship between MTRR A66G polymorphism and breast cancer risk were included by searching PubMed, EMBASE, China National Knowledge Infrastructure and Wanfang Database. Either fixed-effects or random-effects models were applied to calculate odds ratios(ORs) and 95% confidence intervals (CIs) by RevMan5.2 software. Results: A total of 9 studies bearing 7,097 cases and 7,710 controls were included in the meta-analysis. The results were that the combined ORs and 95%CIs of MTRR 66AG, GG, (AG+GG) genotypes were 0.98(0.91-1.05), 1.06(0.97-1.16) and 1.02(0.94-1.10), respectively with p=0.52, 0.19 and 0.65. We also performed subgroup analysis by specific ethnicity. The results of the combined analysis of MTRR 66AG, GG, (AG+GG) genotypes and breast cancer in Asian descent were Z=0.50, 0.53 and 0.21, with p all>0.05; for breast cancer in Caucasian descent, the results were Z=1.14, 1.65 and 0.43, with p all>0.05. Conclusions: Our findings suggested that MTRR A66G polymorphism was not associated with breast cancer susceptibility.

Prevalence and Molecular Characterization of Echinococcus granulosus sensu stricto in Northern Xinjiang, China

Baoping Guo,Zhuangzhi Zhang,Xueting Zheng,Yongzhong Guo,Li Zhao,Ren Cai,Bingjie Wang,Mei Yang,Xi Shou,Wenbao Zhang,Bin Jia 대한기생충학ㆍ열대의학회 2019 The Korean Journal of Parasitology Vol.57 No.2

Echinococcus granulosus is an important zoonotic parasite globally causing cystic echinococcosis (CE) in hu- mans and animals. In this study, prevalence of CE and variation of cox1 gene sequence were analyzed with isolates E. granulosus collected from different areas in northern Xinjiang, China. The survey showed that 3.5% of sheep and 4.1% of cattle were infected with CE. Fragment of cox1 was amplified from all the positive sheep and cattle samples by PCR. In addition, 26 positive samples across the 4 areas were included. The isolates were all E. granulosus sensu stricto (s.s.) containing 15 haplotypes (Hap1-15), and clustered into 2 genotypes, G1 (90.1%, 91/101) and G3 (9.9%, 10/101). Hap1 was the most common haplotype (48.5%, 49/101). Hap9 were found in humans samples, indicating that sheep and cattle reservoir human CE. It is indicate that E. granulosus may impact on control of CE in livestock and humans in the region.