Maintenance of Millimeter-level Geodetic Reference Framework

The high-precision terrestrial reference frame,as the spatial benchmark for geodesy,is an important national infrastructure.However,due to the influence of nonlinear factors related to geophysical phenomena,the overall maintenance accuracy of the ITRF framework is still at the centimeter level.Therefore,accurately characterizing the true trajectories of linear motion,nonlinear motion,and geocentric motion of the reference station is the key to achieve the construction and maintenance technology of a millimeter level terrestrial reference framework.Based on long-term global and regional GNSS observation data,more Chinese geodesy scientists devoted much efforts to the maintenance of millimeter-level geodetic reference framework.The main contributions of this work included the followings:①Dynamic maintenance of millimeter-level terrestrial reference frame;②Research progress on the method of maintenance of regional reference frame based on GNSS;③The progress of CGCS2000 frame maintenance in millimeter level accuracy;④Reprocessing and reanalysis of two-decade GNSS observation in continental China;⑤Research on current GNSS velocity field model and deformation in Chinese mainland;⑥The preliminary realization and evaluation of CTRF2020.

A Reference Framework for Concurrent Engineering

Considering the diversity of methods and tools offered to concurrent engineering, the aspects playing important roles in the concurrent engineering context have been pinpointed as being four core elements which are Activity, Method, Object and Information. Based on these four elements, a reference framework called AMOI is proposed to be the guideline for the systematic concurrent product design. Using the AMOI reference framework, concurrent product development system can be structured into four function models (including the activity model, method model, object model and information model) which are interconnected with each other.

Materials Development for Adult Learners in Teaching Vocabulary

Considering the special needs and the learning styles of their learners, foreign language teachers should use the most effective methods or approaches which are appropriate for their teaching strategies. Redundant or a diverse range of teaching techniques are not meant to use in the process of their learners＇ acquiring new vocabulary items; instead, the most effective and to the point teaching techniques in terms of each language skill should be employed. Efficiency of language learners in terms of their command of the vocabulary can be assessed through their understanding any reading or listening context and managing to be productive in speaking or writing procedures in language acquisition process. Phonological, morpho-syntactic, or socio-pragmatic positions of new lexical items as well as the learners＇ learning styles and multiple intelligences should all be taken into consideration by language teachers so that their learners could really reach an efficient level of vocabulary power. This efficiency has been identified as having a language passport in terms of the proficiency level of the learners within the CEFR （Common European Framework of Reference） for Languages by all EU countries in recent years. Foreign language teachers should try very hard to supply their learners with the required qualifications in every language skill so that they can have a linguistic identity both in their own societies and inter-cultural or multi-cultural contexts. Within this framework, foreign language teachers will hopefully make use of any suggested approach presented in this study so as to widen their learners＇ horizons in language acquisition process.

Determination of 137Cs reference inventories in a large-scale region： A case study in the central-eastern Inner Mongolia Plateau

In isotope 137 Cs tracing studies, it is a premise to determine suitable 137 Cs reference inventory（CRI） plots and the CRI values. Owing to the heterogeneous spatial distribution of 137 Cs deposition in the ground and diverse, or even irregular, operations in sampling and testing procedures, CRI determination is usually faced with many difficulties and uncertainties. In addition, more difficulties occur in an investigation of a large-scale region because of time constraints and measurement cost limitations. In this study, traditional CRI acquiring methods were summarized first, and then a new complex scheme was established, involving seven core steps and coupling the model estimate and sample measurement. The above CRI determination methodology was implemented in the central-eastern Inner Mongolia Plateau. The case study results showed that the CRI in the dark chestnut soil sub-region, located in the east and south of Xing＇an City, exhibited 2447 Bq·m–2; the CRI in the aeolian sandy soil sub-region, positioned in the south central Tongliao City and central Chifeng City, showed 2430 Bq·m–2; the CRI in the sandy chernozem soil sub-region, situated in the northwestern Chifeng City, presented 2384 Bq·m–2; and the CRI in the chestnut soil sub-region, in the southern Xilin Gol City, was 2368 Bq·m–2. The newly proposed CRI determination scheme was proved effective, and the determined CRI plots and CRI values were convincing. The methodology offered a framework for 137 Cs tracing studies in large-scale regions or long-distance transects.