农业工程

Leaving a Mark on the History of Agricultural Engineering： Application of Oral History in Agricultural Engineering Subject

Song Yi

2017, 7(1): 1-6.

Abstract(415) [PDF 1097KB](210)

Abstract:
Agricultural engineering subject originated in Europe and America.And it has a history more than 100 years.The subject was introduced into China in the late 1940s.It was banned in the early 50s and was replaced by agricultural mechanization because of various reasons after founding of the People′s Republic of China.Until the beginning of reform and opening up，it was listed as one of the 25 key disciplines to be strengthened and revitalized and was rebulit.More than 30 years in the past，as a subject of‘engineering of constructing agricultural’，agricultural engineering made great contributions to the grand strategy of China′s‘four modernizations’sync development.Due to historical reasons，early development of agricultural engineering has been blurred.Until recent years，oral history as the starting point，development history track of the subject was collected and arranged.Combining the practice of oral history for agricultural engineering，characteristics of agricultural engineering subject，basic situation of oral history research and confusion in practice were introduced.Thinking and suggestion of producing oral history of agricultural engineering were put forward.

Design and Test of Quality Index for Farmland Residual Film Recovery Operation

Chen Jianlin, Liang Xueqiang, Yun Jie, Qi Guozhang, Li Fengming, Zhang Yi, Liu Xu, Xing Shuo

2017, 7(1): 7-10.

Abstract(425) [PDF 687KB](208)

Abstract:
Based on recovery of waste film and reuse of resources，concept of field debris retention and cleaning rate of effective recovery was put forward in the design of quality index system for farmland residual film recovery operation.Combined with recovery rate of residual film，three constraint indexes was put forward in order to promote technological progress and improve operation quality for residual film recycling machine，and explore assessment method of residual film recovery operation quality.Field test results showed that thickness of plastic film was the factor that influenced collection rate and cleaning rate of effective recovery.Film thickness had little effect on debris retention.Amount of debris retention was related to weather fastness and integrity of plastic film during recovery time.

Research Progress of Controller for Electric Tractor

Mao Pengjun, Yin Shanshan, Min Junjie, Zhang Yalong, Zhang Jiarui, Jiang Kai

2017, 7(1): 11-14.

Abstract(533) [PDF 822KB](199)

Abstract:
Electric tractor is a developing trend of electric low speed vehicle.Relevant domestic colleges and universities have carried out some research on electric tractor controller.Based on analysis of research situation of electric tractor controller，design idea that based on sliding mode variable structure control for brushless DC motor by adjusting torque in order to achieve objective of stable speed was put forward.It provided a reference for development of domestic controllers.

Planting Agronomy and Mechanization Production Technology of Scallion in Zhangqiu

Liu Dandan, Gao Hongwei, Wang Fangyan, Zhou Jianqiang

2017, 7(1): 15-18.

Abstract(549) [PDF 629KB](234)

Abstract:
Scallion is widely cultivated in China as seasoned vegetables and economic crop.And scallion occupies an important position in development of vegetable industry.Planting agronomy of Zhangqiu scallion and research status of mechanized production of scallion at home and abroad were analyzed.Main factors restricting development of scallion production mechanization were expounded.According to planting agronomy and cultivation model，demand of mechanized production equipment and technology development strategy were put forward.

Sustainable Development Strategy of Mechanized Conservation Tillage Technique in Hebei Province

Wang Siao, Feng Xiaojing

2017, 7(1): 19-22.

Abstract(423) [PDF 183KB](194)

Abstract:
According to the characteristics of agricultural industrial structure，evaluation of mechanized conservation tillage technique in Hebei province was carried out.Countermeasures to promote sustainable development and popularization of this technology were put forward in order to solve restriction of land resource shortage on regional economic growth.Benefits and problems of mechanized conservation tillage technique were analyzed.Countermeasures were put forward.First，strengthening technical propaganda and training.Second，doing a good job of experimental demonstration and playing radiation effect of agricultural cooperatives adequately.Third，agricultural machinery combining agronomy，innovativing and improving technology model.Fourth，innovativing service promotion model.Fifth，establishing sound investment mechanism.Last，improving marketing mechanism.

Exploration of Mechanized Harvesting Model for Water Chestnut in Cohesive Soil

Huang Ning, Li Suyun, Li Jin

2017, 7(1): 23-25.

Abstract(362) [PDF 773KB](193)

Abstract:
Several kinds of mechanized harvesting model for water chestnut in cohesive soil were explored combining field investigation and field test.Problems of each model were analyzed.Effective solution was explored.Lack of water chestnut harves using other harvesting machinery was analyzed by experiment and improvement scheme was put forward.Changing agronomic methods and effective combination of agricultural machinery，and research and development ideas of water chestnut special harvester by hierarchical mining were put forward according to growth characteristics of water chestnut.It laid foundation for promotion of mechanized harvest of water chestnut.

9R Series New Tractors of John Deere Company

Wu Qingfen

2017, 7(1): 26-28.

Abstract(368) [PDF 502KB](208)

Abstract:
Technical performance and structural characteristics of main parts of 9R series new tractors of John Deere company were introduced.It provided reference for research institutes and manufacturing enterprise to research and develop new tractors further in China.

Development Practice of Agricultural Mechanization in Hilly and Mountainous Areas of Chongqing City

Qin Dachun, Zhou Bing, Ao Fangyuan

2017, 7(1): 29-31.

Abstract(534) [PDF 448KB](231)

Abstract:
Development of agricultural mechanization in hilly and mountainous areas should be based on the characteristics of hilly and mountainous areas and follow inherent economic law.Core restrictive factors and support of agricultural mechanization development in hilly and mountainous areas were expounded.Ideas，major initiatives and experience of agricultural mechanization development in hilly and mountainous areas of Chongqing city were summarized.It provided reference for development of agricultural mechanization in hilly and mountainous areas of China.

Use and Maintenance of 4QS-1250 Suspension Type Silage Harvester

Jia Jingxia

2017, 7(1): 32-34.

Abstract(394) [PDF 587KB](194)

Abstract:
Structure，working principle and main technical parameters of 4QS-1250 suspension type silage harvester were introduced.Using and adjusting methods of key working parts and trouble solving measures were analyzed.It provided reference for researchers to develop silage harvester and user′s correct use.

Design，Use and Adjustment of 2BFM-9 Type Wheat No-tillage Seeding Machine

Wang Nan, Guo Yong, Jin Baoxing

2017, 7(1): 35-37.

Abstract(383) [PDF 634KB](199)

Abstract:
2BFM-9 type wheat no-tillage seeding machine was designed.Structure，main functional features and design scheme of drive system were analyzed.Use and adjustment methods of main working parts of no-tillage seeding machine were introduced.It provided reference for researchers to design no-tillage seeding machine and user′s using correctly.

Design of Three-dimensional Culture Leaf Device Control System

Zhang Xiaowen, Yao Tao, Chen Lizhen, Bu Yunlong, Zhou Zengchan, Li Shushan

2017, 7(1): 38-41.

Abstract(436) [PDF 918KB](236)

Abstract:
Aiming at limited space in greenhouse and growing large demand，a three-dimensional cultivation system of leafy vegetables was designed.The system consists of motor transmission and cylinder combination.To improve system reliability and operability，PLC control mode，temperature and humidity detection，CO2 detection，position detection and control were used in automatic control system of device.By using light sensor and lifting device，maximum growth of leafy vegetables was achieved.The system was safe，reliable and practical，which provided a good reference for realization of space utilization maximum，mechanization，and automatic control operation in the greenhouse.

Simulation of Spatial Electric Field Distribution Based on ANSYS Maxwell

Yang Xiangfei, Ma Jungui

2017, 7(1): 42-43.

Abstract(593) [PDF 658KB](282)

Abstract:
Electric field distribution of high voltage electrostatic field equipment in greenhouse was simulated using ANSYS Maxwell.Excellent electric field environment was obtained by optimizing equipment wiring.

Effects of Nitrogen from Sewage with Different Treatment Levels on Farmland Soil Environment

Qi Lirong, Guo Zhenmiao, Gao Jiangyong

2017, 7(1): 44-47.

Abstract(426) [PDF 705KB](238)

Abstract:
Soil column model experiment was done for simulating two grades wastewater in soil.The characteristic of nitrogen accumulation and leaching in soil were investigated.For primary treatment of wastewater，experimental results showed that the level of ammonium nitrogen in the sewage basic would not accumulate in soil layers and leached while nitrate and total nitrogen concentration would be accumulated and leached in the depth soil with increase of irrigation frequency.For secondary treatment of wastewater，because of the low nitrogen concentration，concentration of each layer of soil was relatively low，and concentration of nitrogen in the soil was result of interaction of nitrogen in soil and nitrogen in sewage.With increase of irrigation times，the nitrate and total nitrogen had a downward trend.The test results also showed that，compared with secondary treatment wastewater，the first stage treatment of sewage irrigation would bring high pollution risk to soil environment and groundwater environment.

Necessity and Measures of Rural Environmental Education

He Lina, Meng Xiangyu

2017, 7(1): 48-51.

Abstract(338) [PDF 648KB](172)

Abstract:
Environmental problem is an important factor that restricts sustainable development of economy，and it also becomes the biggest obstacle to sustainable development of our country.From present situation of rural environment，necessity of rural environmental education was analyzed.Suggestions on rural environmental education were provided from three aspects：professional education of rural cadres in villages and towns，universal education of rural masses and classroom teaching in rural primary and secondary schools.

Reconstruction of Rice Husk Storage Warehouse′s Structure

Sui Yulin, Zhang Ruchun, Zou Dezhi, Wang Yuqi, Jiang Yang, Zhang Lu, Yu Dianyu, Zhang Zhi

2017, 7(1): 52-54.

Abstract(474) [PDF 466KB](178)

Abstract:
By increasing wall inclination and installation of silo wall vibrator，raw rice husk storage warehouse was transformed to prevent problems that sticking to wall of rice hull，the arch and discharge was not smooth and other issues.At the same time，grain grading equipment—rice husk distributor was installed into hopper to solve automatic classification of rice husk.Thereby many drawbacks，such as big friction between materials，warehouse transportation difficulties，channel blocking，low production capacity，instability of product quality and automatic classification，which caused by small density of rice husk，rough surface texture and hairy thorn，were effectively solved.Thus labor intensity of workers was greatly reduced，degree of automation and mechanization was improved.

Supermarket Food Safety Management and Control

Zhao Tao, Miao Lijun, Chang Rui

2017, 7(1): 55-58.

Abstract(465) [PDF 671KB](237)

Abstract:
With improvement of people′s living quality，problems of food safety have not only stayed in national policy.As an important part of modern fast-paced life，supermarket was becoming more and more important in people′s lives.Supermarket food safety issues have received more and more attention.Some problems of supermarket food safety supervision were discussed from supermarket food safety hazards

Optimization of Horizontal Terrace Ridge Section in Land Consolidation Engineering

Niu Yan, Ji Yafei, Li Juan

2017, 7(1): 59-63.

Abstract(548) [PDF 872KB](195)

Abstract:
In order to study optimization of horizontal terrace ridge section design in land consolidation engineering，influence of different ridge heights and outer slope angles on the land occupation ratio of ridge and cut-fill volumes was analyzed.On this basis，taking land occupation ratio of ridge and cut-fill volumes as evaluation indexes，comprehensive evaluation of ridge section design scheme was preliminary discussed.Results showed that when ridge was higher and outer slope was steeper，land occupation ratio of ridge was smaller，effective tillage area was larger.When ridge was lower and outer slope was slower，cut-fill volumes was smaller，project cost was smaller.Land occupation ratio of ridge and cut-fill volumes was mutually exclusive.Therefore，in the process of horizontal terrace ridge section design in land consolidation engineering，weights of each evaluation index should be determined rationally according to local conditions，so as to determine optimal design scheme of ridge section design.

Structure Optimization of Ear Box Bracket of 4YZS-4 Type Corn for Seed Harvester

Liu Shuping, Tang Zunfeng

2017, 7(1): 64-67.

Abstract(316) [PDF 1607KB](184)

Abstract:
In order to improve the stability of 4YZS-4 type corn for seed harvester，mechanical model of ear box bracket under typical operating conditions was built.By finite element simulation，position of maximum stress and maximum displacement was found and then the structure was optimized.Maximum stress，maximum displacement and maximum displacement of Y direction of ear box bracket reduced by 5.6%，6.8% and 26% after optimization.It provided reference for the future design of corn harvester ear box and bracket.

Design and Experiment of Low-injury Picking Test Table for Fresh-eating Maize

Wang Xianren, Geng Lingxin, Li Xinping, Pang Jing, Zhou Hanmi

2017, 7(1): 68-71.

Abstract(446) [PDF 792KB](190)

Abstract:
Because of good taste and nutrient-rich，fresh-eating maize is becoming more and more people′s favorite.It has a good market prospects.Main problems with machine harvesting of fresh-eating maize are that ear root grains were damaged seriously by picking roller of maize harvesting machine.A low-injury picking test table for fresh-eating maize was designed.Picking test of fresh-eating maize was made.Effects of main structure and parameters of maize harvesting machine on grains damage of fresh-eating maize were researched.The best combination of experimental factors was obtained.The picking test table could provide basic structure and motion parameters for development of fresh-eating maize harvester.

Design and Experiment of Remote Control Sonic Instrument Based on Web

An Hongyan, Zhang Chuanshuai, Xie Jie, Zhang Jingkai, Liu Wang, Sheng Shun, Sun Guiqin, Wang Rongxue

2017, 7(1): 72-74.

Abstract(374) [PDF 650KB](187)

Abstract:
In order to improve level of automation and intelligence of sonic instrument，and reduce labor intensity of managers，a kind of remote control sonic instrument based on Web was designed.During growing period of crops，managers could remotely set up opening or closing time of sonic instrument by Web.It also could automatically adjust audio frequency according to change of air temperature and humidity inside greenhouse.Production test showed that remote control interface was easy to operate and equipment worked stability.Yield per rape plant increased by 17.14% and total output increased by 17.14%.

Design and Simulation of Corn Stalk Quenching and Tempering Device Based on RecurDyn

Wu Hongxin, Yan Chuliang, Yang Xiaogang, Cao Hongguo, Yang Fangfei, Sun Zheng

2017, 7(1): 75-80.

Abstract(294) [PDF 1979KB](151)

Abstract:
Corn stalk conditioning part is the key part of corn harvester and its working performance directly affects the effect of straw conditioning.A new corn stalk quenching and tempering device was designed.Working parts digital prototype and straw model were established by multi-body dynamics simulation technique.Integrated simulation and analysis platform was built.Comprehensive analysis of straw conveying and tempering process was carried out.Results were consistent with physical test process.Conveying，feeding and tempering process of corn straw in operation were reappear better.

Design of Sweet Potato Ridging Fertilizing Machine and Harvester in Hilly and Mountainous Area

Tong Yining, Xu Jinda, Yao Aiping, Lou Tingting

2017, 7(1): 81-83.

Abstract(372) [PDF 557KB](216)

Abstract:
In view of low level of sweet potato planting and harvesting mechanization in Zhejiang province，a new type of four wheeled low-power moving chassis was designed.It configured great circle arc groove surface configuration of digging shovel and wheeled fertilizer applicator.Sub soil ridging forming device was designed.Potato production joint operation equipment was integrated.This machine was suitable for red clay and mountainous area.And it has great significance to promote sweet potato production mechanization in southern China.

Design of 1GK-210 Type Amphibious Rotary Cultivator

Zheng Tao, Wang Jie, Zhu Jianxi, Lin Xue, Chen Changqing, Zhang Jiaqing

2017, 7(1): 84-85.

Abstract(688) [PDF 461KB](182)

Abstract:
1GK-210 type amphibious rotary cultivator was designed.Overall structure was introduced.Main technical parameters were determined.And innovative design of rotary knife roller and plate device was made.This rotary cultivator was not only suitable for paddy field with neutral clay quality in the south of China to complete ploughing，burying stubble，crushing soil，starting pulp，round levelling fields and so on，but also was applicable to dry land grain crop straw returning operation，effect of tillage could meet agronomic requirements of grain crops.

Design of 9KLH-55 Type Caragana Pellet Feed Briquetting Machine

Hao Qiuju

2017, 7(1): 86-88.

Abstract(403) [PDF 837KB](215)

Abstract:
Caragana is one of the most important renewable resources.According to growth and physical properties of Caragana，9KLH-55 type Caragana pellet feed briquetting machine was designed.Structure，working principle，main technical features and parameters of this machine were introduced.Key components were designed.The successful development of 9KLH-55 type Caragana pellet feed briquetting machine for ease of animal husbandry had important significance in the development of forage resources shortage.

Design on a Kind of Small Field Seeding Device for Soybean Breeding Experiment

Zhang Donghui, Shi Guomin, Zhang Hui, Li Wenchun

2017, 7(1): 89-90.

Abstract(358) [PDF 381KB](240)

Abstract:
There are many soybean breeding field planting ways，but they all have obvious shortcomings.A kind of small field seeding device for soybean breeding experiment was designed innovatively.Test results showed that the seeding device improved accuracy of experiment.Its advantages were simple structure，easy to operate and low price，so its popularization and application prospect was vast.

Problems and Suggestions on University Student Innovative Projects Implementation

Han Changjie, Zhang Jing, Yang Jianying, Guo Hui, Yilidaer·Yiliyasi

2017, 7(1): 91-93.

Abstract(474) [PDF 506KB](182)

Abstract:
University student innovative project is a very good innovative practice of comparative system before graduate，which can improve comprehensive qualities for participation students.Combined with experience of guiding college students innovation projects，problems existing in selection，implementation，acceptance and summary of university student innovative projects were introduced.Solutions and suggestions were put forward.

Reform and Practice of Innovative Education in Agricultural Engineering

Guo Wenwen, Ni Zhiwei, Liu Zhishen, Yang Hongguang

2017, 7(1): 94-95.

Abstract(499) [PDF 333KB](212)

Abstract:
As a comprehensive interdisciplinary subject，agricultural engineering is an organic combination of modern science and technology，agricultural industrialization and modernization.Agricultural engineering should not only require students to master basic knowledge of books，but also should reach ability of flexible use，which requires university to pay attention to cultivation of students′ innovative ability，although some colleges and universities have realized importance of innovation in education，but reform and innovation are still in the phase of exploration.Inherit and carry forward the fine tradition of‘unity，diligence，truth-seeking and innovation’in the process of innovation education，establish a‘people-oriented’concept of teaching，promote quality education，adhere to educational innovation，initially established to cultivate students′ innovative spirit and practical ability as the core，it is imperative to reform the teaching system constituted by teaching system practice teaching system，innovation education，innovation education platform，management and operation mechanism reform content.

Reform and Practice of‘Guided Teaching’Model on Fresher Major in Food

Ye Yang, Yuan Xianling, Wang Lingyun, Li Dong, Liu Qingbin

2017, 7(1): 96-98.

Abstract(386) [PDF 516KB](185)

Abstract:
For problems of unstable specialty thought，insufficient professional knowledge，bad learning attitude and underpowered learning on fresher major in Food，reform of‘Guided Teaching’model from teachers，entrance education，practice system，lectures and other aspects was carried on.It could strengthen new professional learning interest and initiative，enhance professional identity，which helped to realize the goal of training high-quality talents.

Research and Practice of Teaching Method for Agricultural Machinery Professional Series Courses

Yang Ranbing, Liu Zhishen, Ni Zhiwei, Yang Hongguang

2017, 7(1): 99-100.

Abstract(245) [PDF 318KB](194)

Abstract:
At present，there are many disadvantages such as narrow professional caliber，poor hands-on ability，old teaching content and single teaching method in the teaching of agricultural machinery specialized courses.So the goal of talent training objective was slower than social and economic development，departet from inherent law of students′ self growth.Reform and exploration of teaching method for agricultural machinery professional series courses were carried out from 4 aspects including teaching idea，teaching model，operational security mechanism and management system.It provided reference for agricultural colleges and universities to construct agricultural machinery specialized courses.

Effect of Hormone Treatment on Seed Germination of Taxus chinensis var.mairei

Bi Chenxi, Meng Jie, Wang Fang, Fan Rong, Paizilaiti·Aierken, Xiakelanmu·Yimingjiang, Bai Yucui, Wen Zhang

2017, 7(1): 101-105.

Abstract(325) [PDF 592KB](179)

Abstract:
In order to study effect of hormone treatment on seed germination and discuss effective hormone concentration ratio of promoting seed germination of Taxus chinensis var.mairei，taking Taxus chinensis var.mairei seeds as experiment material，using orthogonal test design of L25（53），choosing three hormones GA3，6-BA and 2，4-D，concentration gradient of 0，0.25，0.5，0.75 and 1.0 mgL，seed germination rate，germination index，vigor index and mean germination time were measured.Test results showed that germination rate of A1B2C2 was the highest，which was 85.33%.Germination index（6.95）and vigor index（19.25）of A1B1C1 were the highest.Average germination time of A4B2C5 was the shortest，which was 6.04 d.Comprehensive analysis，GA3 0.75 mgL+6-BA 0.25 mgL had the best effect on improving germination rate and shortening germination time.In addition to average germination time，extreme values of other indexes were GA3＞6-BA＞2，4-D，extreme values of mean germination time were 6-BA＞GA3＞2，4-D.GA3 and 6-BA had extremely significant effect（P＜0.01）and significant effect（P＜0.05）on seed germination rate，main effect was GA3＞6-BA＞2，4-D.GA3 and 6-BA had extremely significant effect（P＜0.01）on seed germination index，vigor index and mean germination time，main effect was GA3＞6-BA＞2，4-D.Main effect of mean germination time was 6-BA＞GA3＞2，4-D.Therefore，GA3 was the key factor affecting seed germination rate，germination index and vigor index of Taxus chinensis var.mairei.6-BA was the key factor to promote seed germination of Taxus chinensis var.mairei.Effect of 2，4-D was not obvious.

High Quality Cultivation Technology of Kiwi Fruit in Northwest of Fujian Province

Luo Yueliang

2017, 7(1): 106-107.

Abstract(275) [PDF 342KB](190)

Abstract:
Kiwi fruit is rich in nutrition and it is highly favored by people with high vitamin content.There are many areas of kiwi planting in China.Kiwi in northwest Fujian province is called a famous product in Fujian and even in China.Combined with years of work experience，high quality cultivation technology of kiwi fruit in northwest of Fujian province was introduced.

Influence Factors of Agricultural Technology Extension in Northwest Region： An Empirical Research Based on Shuangzhao Towns of Xianyang City in Shanxi Province

Wang Jinghong, Zhang Shiwei

2017, 7(1): 108-111.

Abstract(276) [PDF 912KB](187)

Abstract:
Popularizing agricultural technology has a great realistic impact on achieving cultivation goal of planting crops with high quality and high yield，improving farmers′ quality of science and technology，and speeding up process of agricultural modernization in China.First，current situation of promoting agricultural technology in Shuangzhao town of Qindu district in Xianyang city of Shanxi province，which located in northwest China，was analyzed.Then，influential factors of agricultural technology extension in northwest region were illustrated.Finally，corresponding suggestions were put forward.

Economic Benefit of Whole Mechanization Technique in Rice Production

Tan Dunyong, Xie Feijun, Zhang Xianqing

2017, 7(1): 112-115.

Abstract(315) [PDF 516KB](186)

Abstract:
Economic benefits of rice mechanized production in paddy field ploughing and leveling，rice seedling cultivation and transplanting，plant protection，harvesting，grain drying and other links were analyzed.At the same time，compared with traditional artificial cultivation，full mechanized production of rice has advantages of low labor consumption，high labor efficiency，stable yield，high output and high input output ratio.It is the only way to solve shortage of labor shortage，high cost and low efficiency in rice production.It is inevitable demand of sustainable development of agriculture.

Influencing Factors of Leisure Agriculture Tourism

Zhang Lejia

2017, 7(1): 116-118.

Abstract(259) [PDF 528KB](200)

Abstract:
Leisure agriculture tourism has become an important channel for agricultural upgrading，but also enriched tourism way for people to close nature.Key factors that influence demand of leisure agricultural tourism were discussed by survey of frequency of leisure agriculture tourism.Tourism preference of leisure agriculture was empirically analyzed.Countermeasures and suggestions on upgrading of leisure agriculture from perspective of consumers were extracted.

Thinking of Deepening Chinese Agricultural Products Export to ASEAN under ‘Belt and Road Initiative’Strategy

Zhou Xiaoyan

2017, 7(1): 119-120.

Abstract(414) [PDF 345KB](188)

Abstract:
Agriculture occupies an important position in economic development of China and ASEAN，and agricultural cooperation is also a major area of bilateral trade.ASEAN is China′s third largest imports source of agricultural products，but also China′s top second regions of agricultural exports.The implementation of‘Belt and Road Initiative’strategy，planed new blueprint for Chinese and ASEAN′s future development，and make us a new thinking to promote development of China′s agricultural exports to ASEAN trade.

2017 Vol. 7, No. 1

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