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Exploring the maximum grain yields (GYs) and GY gaps in maize (Zea mays L.) can be beneficial for farmer to identify the GY-limiting factors and take adaptive management practices for a higher GY. The objective of this work was to identify the optimum maize plant density range and the ways to narrow maize GY gaps based on the variation of the GYs, dry matter (DM) accumulation and remobilization with changes in plant density. Field experiments were performed at the 71 Group and Qitai Farm in Xinjiang, China. Two modern cultivars, ZhengDan958 and ZhongDan909, were planted at 12 densities, ranging from 1.5 to 18 plants m&minus, 2. With increased plant density, single plant DM decreased exponentially, whereas population-level DM at the pre- (DMBS) and post- (DMAS) silking stages increased, and the amount of DM remobilization (ARDM) increased exponentially. Further analysis showed that plants were divided four density ranges: range I (&lt, 6.97 plants m&minus, 2), in which no DM remobilization occurred, DMBS and DMAS correlated significantly with GY, range II (6.97&ndash, 9.54 plants m&minus, 2), in which the correlations of DMBS, DMAS, and ARDM with GY were significant, range III (9.54&ndash, 10.67 plants m&minus, 2), in which GY and DMAS were not affected by density, DMBS increased significantly, and only the correlation of DMAS with GY was significant, and range IV (&gt, 2), in which the correlations of DMBS and ARDM with GY decreased significantly, while that of DMAS increased significantly. Therefore, ranges I and II were considered to be DM-dependent ranges, and a higher GY could be obtained by increasing the population-level DMAS, DMAS, and ARDM. Range III was considered the GY-stable range, increasing population-level DMBS, as well as preventing the loss of harvest index were the best way to enhance maize production. Range IV was interpreted as the GY-loss range, and a higher GY could be obtained by preventing the loss of HI and population-level DMAS.

The shipping industry in Nigeria since the early 1990s has been experiencing a continuous disastrous downturn. Nigerian shipping companies’ participation in international shipping has continued to be very limited. Their presence and impact is hardly felt in the world's shipping industry. Both the national carriers (that is shipping companies with national carrier status) and other indigenous private shipping companies have vessel as well as management problems. These problems have led to the poor performance of the Nigerian shipping industry for over a decade now. The carriers in the industry are not attaining for the country the gains that are supposed to emanate from shipping. This paper points out the importance of shipping to a nation, identifies the problems the country's shipping companies are facing and proffers solutions that include merging of the companies to have strong financial standing and a competitive edge.

The shortest path algorithm is critical for dynamic traffic assignment (DTA) and for the realization of route guidance in ITS. In order to implement the guidance function quickly and accurately, this paper introduces the fluid neural network (FNN) and develops a new parallel method based on FNN and genetic algorithm (GA) for route guidance. A sub-searching process and parameter optimization are employed to improve the performance of FNN. It is indicated by simulation that this method can be used to find the shortest route quickly from the original node to destination node in traffic networks.

In this paper, a traffic volume prediction model is formulated through Kalman filtering theory. The traffic volumes of the next time interval are forecasted with the detected data collected in Changchun, China, which shows that the prediction model has good performance in real-time prediction.