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Hazard avoidance is one of the key stages in the satellite's soft landing process, during which the selection of the landing site would have a huge influence on the satellite safe landing. In this paper, a new design method is presented for determining the landing site selection using Particle Swarm Optimization based on the Moon’s grounds image taken by moon satellite. Applying this method, the problem of hazard avoidance can be converted into the optimization of the value of “obstacle function” after processing the image employing the median filter algorithm. In order to discuss and to compare the efficiency of the different optimization methods, three algorithms including Particle Swarm Optimization, Genetic Algorithm and Global Search Algorithm are tested to solve this problem. The results show that Particle Swarm Optimization has the more satisfactory optimization results and the quickest optimization speed in the landing site selection. The detailed comparisons are introduced in the body paragraph.

Natural activities of 32P ( t 1/2 =14.3 days ) and 33P ( t 1/2 =25.3 days ) in total dissolved P (TDP), suspended particulate matter, net-plankton and rainwater during the spring of 2001 were measured by an ultra-low level liquid scintillation counter. A continuous steady-state model was used to estimate residence times of various phosphorus pools and uptake rates of the biological food chain within the upper ocean of the East China Sea. 32P/33P ratios increased from the dissolved pools to the suspended matter and to net-plankton, reflecting that the age of P increased as one moved up through the food chain. The residence times of P in the dissolved pools of coastal water and mid-shelf area were very short (3–4 days), which suggests that low phosphorus concentrations could support relatively high levels of primary production. A phytoplankton assimilating flux of 189–814 mg C m−2 day−1 and a zooplankton grazing flux of 10–161 mg C m−2 day−1 were also estimated and show that grazing rates of carbon corresponded to 3–20% of primary production. In addition, the particulate organic carbon fluxes from the upper ocean were calculated by directly comparing the measured seawater inventory of 32P and 33P to that measured in rain, and were found to range between 8.5 and 81.0 mmol m−2 day−1. These results show that the naturally produced 32P and 33P can provide much needed information regarding the biogeochemical cycling of P in marine systems and can be of use in the development of ecosystem models that seek to address mechanisms that affect primary production in the ocean.

This paper aims to establish a quantitative trading strategy of commodity futures based on market money flows. Firstly, we use Accumulation/Distribution index to respectively construct the CMF index which represents the ratio of total capital flows to total volume, and the CHO index which represents the exponential moving average of the cumulative capital flows. In view of the different flows of money between buyers and sellers, the establishment of the transaction net volume index VTL is used to describe respectively the flow of money between buyers and sellers. On this basis, the HMM model is introduced, and the above three kinds of indexes are combined to choose the time, at which we execute the stop-loss operation and risk control. Finally, all performance index values of the strategy are as follows: the rate of initial capital return is 193.77%, the annual rate of return is 99.86%, the maximum retracement rate is 15.73%, the Sharpe rate is 2.05 and the price earnings ratio is 4.01.

This paper is concerned with a class of fourth-order nonlinear difference equations. By making use of the critical point theory, we establish various sets of sufficient conditions for the nonex- istence and existence of solutions for mixed boundary value problem and give some new results. Results obtained generalize and comple- ment the existing ones.

In this paper, a fourth-order nonlinear difference equation is considered.By making use of the critical point theory, we establish various sets ofsufficient conditions for the existence and nonexistence of solutions forDirichlet boundary value problem and give some new results. Ourresults generalize and complement the results in the literature.&nbsp

This study presents a strategy for determining the relatively accurate geographical location of an object based on a video or a sequence of images taken at regular intervals. On the basis of a series of solar formulas, a precise object’s shadow length model that includes the latitude and longitude of the photographer is built to describe how the shadow changes. Inputting the shadow length of the object and the creation time of the image into the built model, parameters like the latitude or longitude can be estimated by Particle Swarm Optimization (PSO). To solve the problem that PSO is easy to get stuck into local optima, a compression factor and mutation operation are introduced to the algorithm. Through analyzing the instance, the improved PSO algorithm has demonstrated itself with enhancement in convergence and accuracy. In conclusion, the improved PSO is an effective and precise tool to estimate the geographical location of video or images.

In this paper, we have established a SECADI model on the basis of the traditional epidemic model and under the consideration of factors such as the spread of the disease, the quantity of the medicine in need, the medicine production speedetc. We have improved the crowd classification standard and the spread styledifferential equation model in classical SIR model. We distinguished the crowd into six categories, including the susceptible, the exposed, the curable, the advanced, the dead and the immune, and we established integrated transformation relationships between them after taking control measures through qualitative and quantitative method, and then derive the adequate epidemic differential equation model before taking controls. We applied the method of computer simulation to solve the model, worked out uncertain parameters with the method of parameter identification, and we verified the validity and accuracy of the SECADI model. Meanwhile, we calculated with the actual data of Ebola in the epidemic area in WesternAfrica, simulated the evolution of the epidemic, analyze and offered effective approaches to control the epidemic situation. We further discussed development directions of this model in the end.

The "price to income ratio", which is the most popular house price evaluation method, lacks of enough theoretical support from psychology and sociology. The article attempts to improve it with relative deprivation theory (RD) by measuring the "deprivation of house price for household". The article improves the ordinary measurement method o the degree (level) of RD with membership function. In the end, the article evaluates house price in twelve typical countrie (cities) by average degree of RD and cumulative distribution of degree of RD.

In the last few decades, increasing concern over the environmental impacts of the oil-based vehicles, along with the peak oil, has led to renewed interest in electric vehicles. Electric vehicles used to be considered as the non-pollution transportation, however, queries appears in recent years. As we want to make a comprehensive analysis of the widespread use of electric vehicles, we select the U.S, China, Sweden, and France as representatives based on power generation, location, economic strength, cultural background and social status. In order to fully compare each country, an innovative evaluation method called AGT which is comprehensively put the AHP, Gray Relation Grade Analysis and TOPSIS together is invented. We use the tone operators and fuzzy to clearly illustrate the influence of the widely use of electric car in the four countries and introduce the grade analysis to avoid the error. By the model, according to the 4 countries' comprehensive evaluation values' result, the rank of each country's suitability to the widespread use of electric vehicles is Sweden, US, China, and France. Based on the model's result, we get some conclusions which are unlike the previous studies. In our opinion, thermal-based countries should promote electric vehicles in advance by issuing subsidies to open the market. The right time of the countries which use renewable energy to power generation is until the form of power generation is reformed. And the widespread use of electric vehicles is not the best way to response to energy crisis. Ethanol-fuel vehicles may be more practicable.

Based on the predicted data of lightweight vehicle production from 2010 to 2040, this paper evaluates the environmental and economic impacts of widespread use of electric vehicles. In this paper, the time series, combining membership function, is firstly used to obtain electric vehicle production, and environmental impacts of widespread use of electric vehicles is described. Then, after modeling the economic benefit of widespread use of electric vehicles, the investment cost of renewable energy electricity generation and subsidy cost, the economic impacts are obtained. The result suggests electric vehicles have a promising future with numerous environmental and economic impacts.

Mitochondrial GTPase mitofusin-2 (Mfn2) is a novel gene that remarkably suppresses the injury-mediated proliferation of vascular smooth muscle cells (VSMCs) and has a potential apoptotic effect via the mitochondrial apoptotic pathway. Hepatocellular carcinoma (HCC) tissues and matched normal tissues were examined for mfn2 expression. HCC cells were infected with adenovirus carrying Mfn2 (Ad-mfn2) or green fluorescent protein (Ad-GFP), used as a control. Short hairpin RNA (shRNA) was formed by shR-mfn2 and shR-Bax to repress mfn2 and Bax transcription, respectively. The effects of mfn2 on cell cycle distribution and apoptosis were measured by flow cytometric analysis. Significant downregulation of mfn2 was observed in HCC tissues compared with nearby normal tissues. Overexpression of mfn2 inhibited HCC cell proliferation and induced apoptosis by increasing the level of active caspase-3 and poly (ADP-ribose) polymerase (PARP) cleavage. Overexpression of mfn2 also induced cytochrome c release to the cytoplasm by enhancing Bax translocation from the cytoplasm to the mitochondrial membrane. Upregulation of mfn2 promoted apoptosis of HCC cells, and this was dramatically suppressed by shR-Bax. Our results show that the mfn2 gene is a potential tumor suppressor target that may significantly promote apoptosis via Bax and may inhibit proliferation in HCC cells. This gene may be an important therapeutic target for the treatment of tumors or hyperproliferative diseases.

Hyperplasia suppressor gene (HSG) is a novel gene that markedly suppresses the mitogenetic stimuli or injury mediated by vascular smooth muscle cell proliferation. Herein we provide experimental evidence to show that HSG can also play a key role in tumor proliferation. Down-regulation of HSG protein in hepatocellular carcinoma tissues compared to adjacent tissues. Overexpression of HSG suppressed the growth of liver cancer cell lines, resulted in cell cycle arrest in the G0/G1 phase, increased expression of the cyclin dependent kinase inhibitors (CKIs), and reduced expression of proliferating cell nuclear antigen (PCNA). It also showed that adenovirus-mediated HSG overexpression induced apoptosis. Up-regulation of HSG by adenovirus also significantly suppressed the growth of subcutaneous tumors in nude mice both ex vivo and in vivo. Collectively, our data suggest that HSG is a potential therapy for tumors and possibly other proliferative diseases as well and it has antitumor efficacy on hepatocellular carcinoma by using adenovirus vectors, which may be a new therapeutic target for liver cancer prevention.

In this paper, we make an attempt to introduce rough set theory into an evaluation modeling approach of modern service industry competitiveness. Since its proposal in 1982 by Z.Pawlak, rough set theory has already been successfully applied to a series of research domains. Surprisingly however, the approach has never been applied to modeling industry competitiveness evaluation. In this paper, we design the evaluation index system of modern service industry, build a comprehensive evaluation model based on rough set theory and evaluate the competitiveness of modern service industry in Guangdong compared with the other 13 provinces and cities in China. We further point out the existing problems of the development of modern service industry in Guangdong province and put forward some suggestions.

This paper develops a Gray-Markov model-based approach to predict the municipals water use by combining the grey system theory and Markov random process theory. The proposed approach uses the prediction curve of the grey dynamic forecast model GM(1, 1) as the datum line of the trend of the city water use. Besides, the Markov prediction approach is applied to determine the range of the system chance fluctuation, optimize and modify the grey predictive value. To demonstrate that our system is working correctly, the author used the prediction system to analyze the water data and predict the volume of water use in the city of Zhuhai at a specific time. The approach can not only effectively discover the overall trend of the city water use, but also overcome the influence of the chance fluctuation upon the precision of prediction. Therefore, the approach is effective in real world.

Resource and project optimization scheduling has become the key of the success of researching project in the enterprises. In order to solve the mass resource constrained project scheduling problem, in this paper, an improved particle swarm algorithm (PSO) called particle swarm algorithm with crossover (CPSO) was presented. This improved algorithm is based on PSO and genetic algorithm (GA). Through comparing with SPSO and GA on RCPSP, it is indicated that CPSO not only avoids premature convergence to a high degree, but also keeps a faster convergence rate than SPSO and GA.

The vehicle routing problem (VRP) is a very important combinatorial optimization and nonlinear programming problem in the fields of transportation, distribution and logistics. In this paper, a particle swarm optimization (PSO) algorithm with crossover for VRP is proposed. The PSO algorithm combined with the crossover operation of genetic algorithm (GA) can avoid being trapped in local optimum due to using probability searching. We apply the proposed algorithm to an example of VRP, and compare its result with those generated by PSO, GA, and parallel PSO algorithms. The experimental comparison result demonstrates that the performance of PSO algorithm with crossover is competitive with others and will be an effective method for solving discrete combinatory problems.

Sznajd model, as a developed type of Ising model, has been introduced to simulate and analyze the dynamics of opinion formation and development. This paper aims to analyzing Sznajd opinion formation model on Weighted Networks by updating synchronously. We simulate the public opinion formation processes based on improved Sznajd Weighted Network model with influencing rules. Due to the disappearing of the dictatorship fixed points in the finally results, decisions can be made in a democratic way in this model. All this modifications display interesting dynamics and explain some socio-economic aspects.

Based on modeling and simulation of electricity consumption of phone services and quantified social effect by defining an index, an optimal scheme of phone services is proposed in this paper. From the perspective of a comprehensive consideration of both energy and economy, we recommend an optimal scheme of phone services, which consists of 60% people using cell phones while the other 40% people using landlines household-based.

Inspired by the diffusion movement phenomenon of the molecules, this paper presents a diffusion-repulsion particle swarm optimization (DRPSO). The proposed new algorithm (DRPSO) includes attraction and repulsion (or migration) phases. Once the diversity of population becomes too low, the individuals will be dispersed and carry out diffusion movement, while if the diversity of population becomes too high, the individuals have to be congregated, which is accomplished by diversity control method. Comparisons with standard SPSO and other algorithms on a portfolio problem indicate that DRPSO not only prevents premature convergence to a high degree, but also keeps a more rapid convergence rate than SPSO.

Being an unsupervised learning, conventional k-means clustering algorithm suffers from the limitation which includes the dependence on prior knowledge to specify cluster parameter k and the sensitivity to initial centers. In this paper, we proposed a new k-means algorithm with meliorated initial centers, which obviates the needs of cluster parameter and can select effective initial centers skillfully. Firstly, it uses a cluster-validity-index based method to determine the optimal number of clusters k; then, computes the densities of the area where the data objects belongs to, and finds k data objects all of which are from high density area and the most far away from one another; finally, use these k data objects as the initial centers for further k-means clustering. The application of this new k-means algorithm to partition of diet structures shows its feasibility and validity.

This paper proposes an improved Grey-Markov forecasting dynamic method based on unbiased grey system theory and fuzzy classification. The new forecasting method is named unbiased Grey-fuzzy-Markov Chain method, which can take advantage of the prediction power of conventional Grey-Markov forecasting method and at the same time eliminate grey bias and improve anti-jamming performance. As an example, we use the statistical data of the number of Chinese international airlines from 1987 to 2006 for a validation of the feasibility and practicability of the improved Grey-Markov forecasting model.

AIM: To demonstrate that caudate lobectomy is a valid treatment in cases of hepatocellular carcinoma (HCC) rupture in the caudate lobe based on our experience with the largest case series reported to date. METHODS: A retrospective study of eight patients presenting with spontaneous rupture and hemorrhage of HCC in the caudate lobe was conducted. Two patients underwent ineffective transarterial embolization preoperatively. Caudate lobectomy was performed in all eight patients. Bilateral approach was taken in seven cases for isolated complete caudate lobectomy. Left-sided approach was employed in one case for isolated partial caudate lobectomy. Transarterial chemoembolization was performed postoperatively in all patients. RESULTS: Caudate lobectomy was successfully completed in all eight cases. The median time delay from the diagnosis to operation was 5 d (range: 0.25-9). Median operating time was 200 min (range: 120-310) with a median blood loss of 900 mL (range: 300-1500). Five patient remained in long-term follow-up, with one patient becoming lost to follow-up at 3 years and two patients currently alive at 7 and 19 mo. One patient required reoperation due to recurrence. Gamma knife intervention was performed for brain metastasis in another case. Two patients survived for 10 and 84 mo postoperatively, ultimately succumbing to multiple organ metastases. CONCLUSION: Caudate lobectomy is the salvage choice for HCC rupture in the caudate lobe. Local anatomy and physiologic features of the disease render caudate lobectomy a technically difficult operation. Postponement of surgical intervention is thus recommended while the rupture remains hemodynamically stable until an experienced surgeon becomes available. Prognosis is confounded by numerous factors, but long-term survival can be expected in the majority of cases.

By making use of the critical point theory, the existence of periodic solutions for fourth-order nonlinear difference equations is obtained. The proof is based on the Saddle Point Theorem in combination with variational technique. The problem is to solve the existence of periodic solutions of fourth-order nonlinear difference equations. Results obtained complement the existing one.