In the context of the urban agglomeration and the rapid development of rail transit, the planning of the Beijing-Tianjin-Hebei Region (BTHR) rail transit 2020 is attracting attention. The BTHR is a natural disaster-prone area and a high-risk area for terrorist attacks; the robustness of the area is critical to the sustainable development of North China. Therefore, it is necessary to analyze the...

To clarify the mechanisms that support the continuity of actively cycling tissues of long-lived organisms, we investigated the composition of a mouse spermatogenic stem cell system by pulse-chase of the undifferentiated spermatogonia, the population responsible for stem cell functions, in combination with transplantation and regeneration assays after pulse-labeling. We demonstrate that in addit...

The train derailment is one of the major accidents in rail transit safety system. The reach uses collision accident of rail transit train in Tokyo and Shanghai as the case. Firstly, it present fishbone diagram to qualitatively analysis main factors in derailment. Then it set up a derailment accident tree model with the qualitative and quantitative analysis of. The results show that illegal oper...

Bus stops attain their importance to the transit service from being the main points of contact between the passenger and the bus. Considering spatial attributes, both the location and the spacing of bus stops significantly affect transit service performance and passenger satisfaction, as they influence travel time in addition to their role in ensuring reasonable accessibility. Knowing that ever...

Local bus network is the most popular transit mode and the only available transit mode in the majority of cities of the world. Increasing the utility of this mode which increases its share from urban trips is an important goal for city planners. Timetable setting as the second component of bus network design problem (network route design timetable setting vehicle assignment crew assignment) hav...

We utilize the situation calculus to develop a logical model of hypertext systems. The work builds upon the earlier work of Bieber and Kimbrough in the logical modeling of hypertext systems. In our presentation, a particular version of the situation calculus (which includes a language for programming complex actions) developed for the modeling of dynamic worlds and for the control of robotic ag...

Mathematical models for the electrical activity in cardiac cells are normally formulated as systems of ordinary differential equations (ODEs). The equations are nonlinear and describe processes occurring on a wide range of time scales. Under normal accuracy requirements, this makes the systems stiff and therefore challenging to solve numerically. As standard implicit solvers are difficult to im...