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With the rapid development of China’s logistics technology, four-way-shuttle based storage and retrieval system( FWSBS/ RS) is gaining more and more attention by virtue of its flexibility, convenience and efficiency as a new automated storage technology, but it takes more time for the conventional simulation, which brings inconvenience to the early planning and modeling of the logistics system. Based on Flexsim, an automatic 3D modeling system of four-way shuttle with user-defined parameters is developed by using the idea of automatic modeling. The corresponding task list was automatically executed and the warehousing operation was performed. The utilization rate of relevant equipment and the efficiency of the system were counted. The system makes modeling more efficient and convenient, In addition, it reduces the difficulty of using Flexsim and extends its application in intelligent manufacturing simulation. The example application shows that the system has excellent performance and good interactivity, which can better meet the needs of planners and designers.

Two-dimensional electronic spectroscopy is a kind of nonlinear optical spectroscopy with both high time resolution and high frequency resolution. It can be used to observe the complex dynamics of a condensed molecular system. Meanwhile it is a very powerful tool to study the coherence between the electronic states or electronic and vibration states. In 2007, Flemming's group reported the long-lived quantum coherence observed in the energy transfer process in the light-harvesting antenna protein complex Fenna-Matthews-Olson at 77 K by means of two-dimensional electronic spectroscopy. Though it has been proved not to arise from the pure electronic coherence later, this discovery has greatly stimulated the exploration of the coherent energy transfer pathways possibly existing in the natural and artificial photosynthetic systems, and this is still a very active area nowadays. Here in this paper we briefly review the principle and set-up of the two-dimensional electronic spectroscopy, and also some of its applications in investigating coherent energy transfer in the photosynthetic and artificial systems, aiming to bring this novel spectroscopic tool into a wider application.

With the intensification of competition, enterprises pay more and more attention to logistics network construction and improvement. Optimizing logistics network is regarded as the key way to raise supply chain efficiency. This paper focuses on the definition and analysis of 4/R/I/T logistics network structure which is widely used in distribution logistics system, and puts forward 0-1 programming model to minimize logistics cost based on 4/R/I/T network structure. The model takes into the restriction of service time limit and sole service characteristics account. This optimization model can be solved by Lingo. An example is given in the end, which introduces the application of this model in a medicine distribution logistics network planning.

We design and experimentally demonstrate some negative dispersion mirrors with optimized Gires-Tournois interferometers. The mirror structure is composed of 38 alternating Ta2O5 and SiO2 layers and could be regarded as two sections: high-reflectivity section consisting of a series of quarter-wavelength optical thickness stacks and negative-dispersion section consisting of only 13 layers. The designed mirrors exhibit the expected performance. These mirrors were fabricated by using ion beam sputtering. By adopting such mirrors, dispersion of a mode-locked femtosecond Ti:sapphire laser has been compensated for mostly. With two series of the mirrors, 32 fs and 15 fs pulses have been obtained respectively.

The negative nonlinear index of a semiconductor saturable absorber mirror (SESAM) was investigated by using the reflection Z-scan technique. This is an experimental demonstration, for the first time to our knowledge, that the SESAM possesses comparable negative nonlinear index n2 = ?2.35?10?10?esu, which may have important implications in design and alignment of Kerr-lens mode-locking based on the self-focusing effect.

In order to present a feasible evaluation system for logistics centre design and help the actual project decision, this paper established a quantitative and multi-level evaluation indices system of logistics center designs, created a combination evaluation model based on hierarchical structure, used efficacy coefficient method to standardize the indices values of different dimensions, adopted the subjective and objective integrated method of weighting coefficient, and provided an evaluation model solving method of from-bottom-to-top. At last, an actual project was showed as example to interpret the feasibility of the methods above, which obtain a good expected effect.

Product quality control and management has been so different in supply chain environment. Companies should control not only their own products but also the products and the factors that influenced the products from their supplier. In this paper, control charts and process capability analysis will be used for the management of supplier quality control to help the supplier reach the needed quality level. The method in this paper has already been used in some medical equipment company, and we achieved the expected goals, so the method is effective and valuable for most companies.

With the RFID technology applied to warehouse management to enhance the efficiency of warehousing operations, the operator can collect material information flexibly and easily. Different RFID management software communicates with the hardware more or less in the same way. Through the development of reusable middleware communicating between hardware and software and packing it with storage operations, a package of storage middleware is established. The storage middleware can reduce the complexity of the development of RFID management software, thereby simplifying the storage business processes. In this paper, the work process and the application in warehousing operation of the storage middleware will be introduced.

Pick-to-light has been applied in logistics to support goods picking. Usually, the equipment supplier provides the goods application to the users. But with the development of the user business, the system will be required to be adjusted to meet the needs of the new goods pick work flow, especially to support multi ways of goods picking. This paper studied the low level communication between pick-to-light and monitor workstation, and developed a set of middleware to meet the pick-to-light picking system modification. The middleware is developed with Java language, and can be reused freely. With the middleware, the programmer can develop the pick system according to the adjustment of goods pick work flow. It is very convenient for logistics enterprises and education organizations to construct the goods picking system based on pick-to-light.

RFID has been applied in many industries, especially in logistics. Usually, RFID is used as an identification that replaces barcode or combined with barcode. RFID has many advantages, for example, it can be read fast and improves the efficiency of data gathering. This paper introduces a RFID application system in warehouse management that is used to identify cargo when inbound and outbound. Based on Java language, this paper develops low level communication functions, which can implement the communication between monitoring computer and RFID reader. The cargo inbound and outbound business procedures are designed to show the RFID application in logistics warehouse operation.

Increased competition in the transport market has led to more focus on enterprise's logistics network. To build and improve the integration of logistics network is regarded as the key way to improve supply chain efficiency. This paper firstly focuses on the hub-and-spoke network structure which is widely used in road freight transport system, and by taking into account the restriction of sole service characteristics and service capacity limit, puts forward a hybrid hub-and-spoke network structure to optimize the road freight transport network; then, the paper sets up the total cost model of the network and carries on scientific quantization to every combination of the cost through exhaustive analysis to the cost; lastly, the paper introduces a (0,1) optimization mathematics model to optimize the transit lines based on the lowest total cost of hybrid hub-and-spoke network structure. A practical application to a third-party logistics provider is also described.

Pallet pooling system establishes a considerable number of pallet recycling stations throughout the country to recycle and maintain the pallets. The main advantages of the pallet pooling system are greatly improving the logistics efficiency by achieving pallet through transport, reducing the total number of social pallets by renting the pallets and can reduce the cost of the international logistics. RFID (Radio Frequency Identification) is one of the automatic identification technologies. RFID utilizes the non-contact data exchange to identify the object, which has many advantages such as rapid identification, wear-free, out of the environmental impact, long life, etc. RFID has been developing quickly at home and abroad, which has been widely used in many fields such as industrial automation, commercial automation, control and management of transport. In this paper, the author describes how to use RFID technology on pallets for information management in pallet rental system. Firstly, the author introduces orderly what pallet rental system is, why we need to establish pallet rental system, how to establish such a system, why we should make use of RFID technology and how to use RFID technology in the pallet rental information system; Secondly, the author makes an analysis on the overall structure of the system, information flow and business process in the pallet rental system; Finally the author gives an application of pallet rental information system based on RFID.

Because of the special environment and the risk of accident in the coal mine, some of the major problems that concern the people are the safety production, managing and rescuing workers under the mine. To solve these problems, this paper brings out the Underground Personnel Position System with RFID (Radio Frequency Identification technology). RFID is a new wireless communication technology and widely applied in other industry. The technology can be used to automatically identify the information of the workers, locate their positions on time and record their tracks, which can improve the information management level of the coal mine greatly and provide the necessary information for management and rescuing. In addition, GIS is also used to provide a visual window to assist the Position System to make a more convenient management on the workers' location. It is clear that the GIS-based Mine Safety Management Information System can absolutely achieve a better impact with the seamless link of spatial data whose format is called SHP and some else property data. And the system can greatly improve the efficiency of the mine safety management.

Modern distribution center is a complex logistics system, which is composed of many storage zones and picking zones, and includes many operation patterns with different equipments. Its scientific and rational planning and design are very important to build an efficient distribution center. The needs analysis, capacity planning and the detailed planning syllogism distribution center system planning methodology,the capacity planning model based on the orders data analysis and the equipment allocation model based on storage and picking pattern model are put forward, after doing long-term research on distribution center system planning. The basic storage unit design, the overall capacity planning, storage area planning, process flow designing, and storage area capacity planning based on EIQ-PCB etc are expounded. Finally the application of the methodology in medicine distribution center system planning is introduced.

Birefringent microstructure fibers are shown to allow efficient gereration of anti-Stokes line emission as a result of four-wave-mixing in higher mode by using unamplified femtosecond Ti:sapphire laser pulses.Intense blue-shifted lines with different central wavelength were generated in the high-delta (i.e.high-air filling in the cladding) microstructure fiber with axis sizes 50 and 46 μm by femtosecond laser pulses with 35-fs in duration,820nm in central wavelength and 4nJ in energy per pulse.The experimental result shows that phase-matched four-wa ve mixing in higher-order modes of microstructure fibers allows unprecedentedly high efficiencies of anti-Stokes frequency conversion to be achieved for subnano joule femtosecond laser pulses.The dependence factor of the four waves mixing in birefringent microstructure fiber is compared and analyzed.Good agreement betwe en the theory and experiment is achieved.

In this letter, we systematically investigated the temporal and spectral characteristic of ultra-broad band Ti:sapphire oscillator in femtosecond regime. Pulse formation in temporal regime was observed while the spectral shape evolved fro m hyperbolic secant shape into multi-peak one and the bandwidth increased from 40 to 180nm. Experimental results showed that pulse shortening mainly occurred n ot at its bottom part but at its central section while the spectrum was broadene d, and at the same time the relative energy at the bottom part increased.

The five-mirror laser cavity containing a semiconductor saturable absorber mirror (SESAM) with negative Kerr effect is theoretically analyzed for the first time. It shows that, compared with the cavity without a SESAM, the upper stable range of the resonator expands obviously after the introduction of SESAM. This indicates that the work point for self-starting can be more close to the edge of the stable range of the CW state, and then get higher nonlinear effect. This shows that the negative Kerr effect of the SESAM can contribute to the self-starting of the modelocked laser besides the saturable absorption mechanism.

A Ti: sapphire oscillator emitting an octavespanning spectrum that ra nges from 460nm to 1000nm is demonstrated. To our knowledge, it is the first tim e that a supercontinuum extending beyond 500nm in the blue end is generated from a femtosecond oscillator. The selfQswitched and selfmodelocked Ti: sapphi re oscillator uses chirped mirrors and a prism pair for dispersion compensation. Th ese results will make the measurement of carrierenvelope offset frequency simp ler and improve the stability of optical frequency metrology at the same time.

An experimental study of supercontinuum generation in a photonic crystal fiber with zero dispersion wavelength 780?nm by femtosecond laser and its dependence factor is presented. Supercontinuum light with a spectrum more than one octave broad (500-1100?nm) was generated in a photonic crystalfiber by femtosecond pulses from a selfstarting, selfmode locked Ti:sapphire oscillator running at center wavelength of 810-840?nm. Different supercontinuums were generated by the 35?fs pulses with different power, central wavelength, prechirp, and the continuous noise in the femtosecond pulses. Some reasonable analysis result is obtained from the comparisons of the experimental results, and the mechanism of the supercontinuum generation is analyzed.

A random distributed microstructure fiber in which strong asymmetry was introduced around a puresilica core was reported. Femtosecond laser pulses with duration of 35?fs from a Ti:sapphire laser oscillator were coupled into this fiber, and then periodic color rings were observed from the side of the fiber when the supercontinuum light propagated along the fiber. We attributed this phenomenon to the polarization beating of the supercontinuum light in this highly birefringent microstructure fiber. Measurement showed that the fiber had a beat length of approximately 1?mm at a central wavelength of 600?nm, which is in good agreement with the result of calculation. A new method is proposed to measure the beat length directly in a highly birefringent microstructure fiber.