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To select a more appropriate cooling method for a reflection mirror of Spatial and Spin (S2 ) beam-line at SSRF (Shanghai Synchrotron Radiation Facility), both of the internal cooling method and side cooling method were proposed and compared at various selected energy points (the most important: 50 eV, 80 eV, 100 eV and 867 eV) based on finite element analysis (FEA). For the internal cooling mode, several internal rectangular channels were drilled under the irradiation surface of mirror. For the side cooling mode, two pieces of perforated copper blocks in contact with two side surfaces of mirror were employed. Moreover, a series of side cooling modes with different tube lengths (145 mm, 200 mm, 225 mm, 248 mm and 250 mm) were analyzed. It was found that the side cooling mode with tube length of 248 mm indicated the best slope error results in all of the side cooling methods. By comparing the temperature, thermal stress distribution and slope error between the internal cooling mode and side cooling mode with tube length of 248 mm, it showed that all of the above mentioned indicators for both cooling modes were consistent with the design standards. However, the internal cooling mode presented the better results than this specific side cooling mode. In particular, by comparing some critical important influencing factors, such as the commercial cost, manufacturing process difficulty, manufacturing period and micro vibration issues, the side cooling mode with tube length of 248 mm presented better engineering operability, thus it was selected as the final cooling method for the reflection mirror of Spatial and Spin (S 2) beam-line at SSRF.

The cooling structural design and thermal analysis of three representative high heat load components, namely fixed maskers (FM1, FM2-1 and FM2-2) in the first ultra-high heat-load front-end of the ultra-hard multi-functional x-ray beamline (BL12SW) at SSRF are carried out based on finite element analysis (FEA). By establishing the finite element models, and combining with the performance acceptance criteria of the materials under high heat load, the temperature distribution and thermal stress distribution of the components are analyzed, respectively. In addition, the influence of applied processing materials (oxygen-free high conductivity copper (OFHC), Glidcop®AL-15 and CuCrZr) and convection heat transfer coefficient (i.e., film coefficient, which can be controlled by the adjustment of flow value or the specific structural design) on the thermo-dynamic performance of the high heat load components is also explored to guide the structural, parametric and performance design of the high heat load elements at the synchrotron front-end.

The performance of three kinds of masks: pre-mask, splitter mask and fixed mask-photon shutter, used for the first canted-undulator front end under heat loads at SSRF, is studied. Because these components are shared with two beamlines, the X-rays from both dual undulators and bending magnets can strike on them. Under these complicated conditions, they will absorb much more thermal power than when they operate in usual beamline. So thermal and stress analysis is indispensable for their mechanical design. The method of applying the non-uniform power density using Ansys is presented. During thermal stress analysis, the normal operation or the worst possible case is considered. The finite element analyses results, such as the maximum temperature of the body and the cooling wall and the maximum stress of these components, show the design of them is reasonable and safe.

Based on finite element analysis of thermal mechanical behavior, structural optimization design was proposed for a side cooling collimating mirror subjected to high heat load for a beamline at SSRF (Shanghai Synchrotron Radiation Facility). The temperature distribution, stress concentration effect, maximum equivalent (von-Mises) stress, and slope error of the mirror were analyzed. In particular, the cooling water channels of the traditional structural design were optimized, and the modified designs were further optimized. Although the traditional structural and the improved designs could meet requirements for the temperature and thermal stress, the deformation gradients were relatively large for several structural designs, and this led to larger slope error. The further improved structural designs could be of better performance.

With the rapid development of wind power technology and industry, the structural loads become a limiting factor for safe wind turbine operation and wind turbine operation life. In this paper we present a design of dynamic torsional load control and the design are based on fuzzy control. Simulations are presented to demonstrate the efficiency of our design.

A new ultrahigh-energy-resolution and wide-energy-range soft X-ray beamline has been designed and is under construction at the Shanghai Synchrotron Radiation Facility. The beamline has two branches: one dedicated to angle-resolved photoemission spectroscopy (ARPES) and the other to photoelectron emission microscopy (PEEM). The two branches share the same plane-grating monochromator, which is equipped with four variable-line-spacing gratings and covers the 20–2000 eV energy range. Two elliptically polarized undulators are employed to provide photons with variable polarization, linear in every inclination and circular. The expected energy resolution is approximately 10 meV at 1000 eV with a flux of more than 3 × 1010 photons s−1at the ARPES sample positions. The refocusing of both branches is based on Kirkpatrick–Baez pairs. The expected spot sizes when using a 10 µm exit slit are 15 µm × 5 µm (horizontal × vertical FWHM) at the ARPES station and 10 µm × 5 µm (horizontal × vertical FWHM) at the PEEM station. The use of plane optical elements upstream of the exit slit, a variable-line-spacing grating and a pre-mirror in the monochromator that allows the influence of the thermal deformation to be eliminated are essential for achieving the ultrahigh-energy resolution.

Here, in order to reduce tangential slope errors along the centreline of a first mirror's surface, a side-cooling scheme is proposed. The length of the contact area between the mirror and cooling blocks should be smaller than the beam footprint along the mirror. By optimizing the length and the height of the contact area, reduced slope errors can be obtained. Using this scheme the maximum temperature is not located at the centre of the footprint but shifts to both sides, which fundamentally changes the temperature distribution and enhances the cooling effect compared with the traditional method. This paper presents a `design of experiment' analysis for four kinds of cooling schemes. The structure of the mechanical clamps is also described.

In this paper, the method of conflict analysis based on rough set is applied to investigate the satisfactions of the optimized decision of the water resources allocation in the inland river basin of arid regions. Analyzing the support of the decision for the special districts (e.g., upriver, middle-river and downriver), respectively, in the inland river basin of arid regions, the feasibility of an allocation scheme is investigated. Using the conflict analysis, the injustice of the water resources allocation will be decreased as much as possible. Furthermore, it can also decrease the risk of the fault for some decisions. Therefore, the method proposed in this paper could offer a scientific, dependable theory basis for the decision-makers of the government management branches.

In this paper, the rough set approach is applied to water resources allocation in the inland river basin of arid region. A decision table of the water resources allocation in the inland river basin of arid regions is established by the real situations of the basin. Then, an optimized allocation scheduling is gained by the attribute reduction and the core computation for the decision table. As a test, an example is studied. The exemplary computation showed that not only the results are rational, but the methods are also more useful in practices. Meanwhile, the problem of allocation imbalance of water resources of the classical methods in the region studied is solved. Therefore, it provides a more reasonable and powerful method for the government management branches.

The performance of optical elements in the beamline is very sensitive with the deformation caused by high heat loads, which require special cooling methods to preserve the quality of the photon beam. In the paper, the thermal analyses of two kinds of mirrors are presented. One of mirrors made of silicon is used to collimate X-ray; another mirror made of copper is used to reflect infrared light. Different indirect water cooling methods, side cooling and bottom cooling, are adopted for them. By means of optimization design using Ansys software, better slope of two mirrors is achieved. Optimization procedures for reducing their slope error are also described.