Container shipping is one of the most important transport modes in international trade. For a large-scale container shipping network, an optimisation model is proposed to minimise the total shipping cost of container flow. Considering the directional property of the container shipping process, a steering vector search pattern is incorporated in a Max-Min Ant System (MMAS) solving algorithm, and an orthogonal array method is adopted in parameter settings. In numerical experiments, a traditional ant colony algorithm and an MMAS algorithm based on a steering vector search pattern are used respectively to optimise the network of five node scales. The results show that a steering vector search pattern can speed up the computation process and improve the optimisation effect.

In this paper, the definition of seaport fairway capacity, considering port service level, is given by referring to both road and inland waterway capacity combined with the features of coastal fairways. In view of the navigation environment and ships' behaviour, the safety distance of ships entering and leaving a seaport is chosen as an overall index to evaluate the navigational safety level of a fairway. Based on the ship-following theory, an Arena-based seaport operating system simulation model is constructed to analyse the impact of safety level on seaport fairway capacity. For different navigational safety levels (i.e., minimum, general and adequate), seaport fairway capacity corresponding to different service levels and navigation durations is obtained. The results show that fairway capacity varies with safety level for a given port service level, and the lower the safety level is, the higher the fairway capacity is. Finally, a recommended navigational safety level and its associated fairway capacity are given to provide a theoretical foundation for fairway design and management.

Escherichia coli (E. coli) is the most widely applied model organism in current biological science. As a widespread opportunistic pathogen, E. coli can survive not only by symbiosis with human, but also outside the host as well, which necessitates the evaluation of its response to the space environment. Therefore, to keep humans safe in space, it is necessary to understand how the bacteria respond to this environment. Despite extensive investigations for a few decades, the response of E. coli to the real space environment is still controversial. To better understand the mechanisms how E. coli overcomes harsh environments such as microgravity in space and to investigate whether these factors may induce pathogenic changes in E. coli that are potentially detrimental to astronauts, we conducted detailed genomics, transcriptomic and proteomic studies on E. coli that experienced 17 days of spaceflight. By comparing two flight strains LCT-EC52 and LCT-EC59 to a control strain LCT-EC106 that was cultured under the same temperature conditions on the ground, we identified metabolism changes, polymorphism changes, differentially expressed genes and proteins in the two flight strains. The flight strains differed from the control in the utilization of more than 30 carbon sources. Two single nucleotide polymorphisms (SNPs) and one deletion were identified in the flight strains. The expression level of more than 1000 genes altered in flight strains. Genes involved in chemotaxis, lipid metabolism and cell motility express differently. Moreover, the two flight strains also differed extensively from each other in terms of metabolism, transcriptome and proteome, indicating the impact of space environment on individual cells is heterogeneous and probably genotype-dependent. This study presents the first systematic profile of E. coli genome, transcriptome and proteome after spaceflight, which helps to elucidate the mechanism that controls the adaptation of microbes to the space environment.

At the summit of the Antarctic plateau, Dome A offers an intriguing location for future large scale optical astronomical observatories. The Gattini Dome A project was created to measure the optical sky brightness and large area cloud cover of the winter-time sky above this high altitude Antarctic site. The wide field camera and multi-filter system was installed on the PLATO instrument module as part of the Chinese-led traverse to Dome A in January 2008. This automated wide field camera consists of an Apogee U4000 interline CCD coupled to a Nikon fisheye lens enclosed in a heated container with glass window. The system contains a filter mechanism providing a suite of standard astronomical photometric filters (Bessell B, V, R) and a long-pass red filter for the detection and monitoring of airglow emission. The system operated continuously throughout the 2009, and 2011 winter seasons and part-way through the 2010 season, recording long exposure images sequentially for each filter. We have in hand one complete winter-time dataset (2009) returned via a manned traverse. We present here the first measurements of sky brightness in the photometric V band, cloud cover statistics measured so far and an estimate of the extinction.

HRCAM (High Resolution CAMera) is a Canon 50D 15-megapixel digital SLR camera equipped with a Sigma 4.5 mm f/2.8 fish-eye lens. It was installed at Dome A on the Antarctic plateau in January 2010 and photographs the sky every 15 minutes. Primarily functioning as a site-testing instrument, data obtained from HRCAM provide valuable statistics on cloud cover, sky transparency and the distribution and frequency of auroral activity. We present a first look at data from HRCAM during 2010, including an overview of how we intend to reduce the images. We also demonstrate the potential of stellar photometry by using linear combinations of the in-built Canon RGB filters to convert instrumental magnitudes into the photometric BVR bands.

In 2008 January the 24th Chinese expedition team successfully deployed the Chinese Small Telescope ARray (CSTAR) to Dome A, the highest point on the Antarctic plateau. CSTAR consists of four 14.5cm optical telescopes, each with a different filter (g, r, i and open) and has a 4.5°×4.5° field of view (FOV). Based on the CSTAR data, initial statistics of astronomical observational site quality and light curves of variable objects were obtained. To reach higher photometric quality, we are continuing to work to overcome the effects of uneven cirrus cloud cirrus, optical “ghosts” and intra-pixel sensitivity. The snow surface stability is also tested for further astronomical observational instrument and for glaciology studies.

Despite the absence of artificial light pollution at Antarctic plateau sites such as Dome A, other factors such as airglow, aurorae and extended periods of twilight have the potential to adversely affect optical observations. We present a statistical analysis of the airglow and aurorae at Dome A using spectroscopic data from Nigel, an optical/near-IR spectrometer operating in the 300–850 nm range. The median auroral contribution to the B, V and R photometric bands is found to be 22.9, 23.4 and 23.0 mag arcsec−2 respectively. We are also able to quantify the amount of annual dark time available as a function of wavelength; on average twilight ends when the Sun reaches a zenith distance of 102.6°.

From theoretical analysis and site testing work for 4 years on Dome A, Antarctica, we can reasonably predict that it is a very good astronomical site, as good as or even better than Dome C and suitable for observations ranging from optical to infrared & sub-mm wavelengths. After the Chinese Small Telescope ARray (CSTAR), which was composed of four small fixed telescopes with diameter of 145mm and the three Antarctic Survey Telescopes (AST3) with 500mm entrance diameter, the Kunlun Dark Universe Survey Telescope (KDUST) with diameter of 2.5m is proposed. KDUST will adopt an innovative optical system which can deliver very good image quality over a 2 square degree flat field of view. Some other features are: a fixed focus suitable for different instruments, active optics for miscollimation correction, a lens-prisms that can be used as an atmospheric dispersion corrector or as a very low-dispersion spectrometer when moved in / out of the main optical path without changing the performance of the system, and a compact structure to make easier transportation to Dome A. KDUST will be mounted on a tower with height 15m in order to make a full use of the superb free atmospheric seeing.