固定权数平均数指数的方法论意义

平均数指数作为独立意义的总指数与作为综合指数变形形式的平均数指数无论其内容还是形式都发生了变化。这一变化是基于平均数只是量的一种表现形式的结果。固定权数平均数指数体现了平均数作为一种统计方法的应用。

Morphology and controlling factors of the longitudinal profile of gullies in the Yuanmou dry-hot valley

The morphology of the gully longitudinal profile （GLP） is an important topographic index of the gully bottom associated with the evolution of the gullies. This index can be used to predict the development trend and evaluate the eroded volumes and soil losses by gullying. To depict the morphology of GLP and understand its controlling factors, the Global Positioning System Real-time Kinematic （GPS RTK） and the total station were used to measure the detail points along the gully bottom of 122 gullies at six sites of the Yuanmou dry-hot Valley. Then, nine parameters including length （Lt）, horizontal distance （Dh）, height （H）, vertical erosional area （A）, vertical curvature （Co）, concavity （Ca）, average gradient （Ga）, gully length-gradient index （GL）, normalized gully length-gradient index （Ngl）, were calculated and mapped using CASS, Excel and SPSS. The results showed that this study area is dominated by slightly concave and medium gradient GLPs, and the lithology of most gullies is sandstone and siltstone. Although different types of GLPs appear at different sites, all parameters present a positively skewed distribution. There are relatively strong correlations between several parameters： namely Lt and H, Dh and H, Lt and A, Dh and A, H and GL. Most GLPs, except three, have a best fit of exponential functions with quasi- straight shapes. Soil properties, vegetation coverage, piping erosion and topography are important factors to affect the GLP morphology. This study provides useful insight into the knowledge of GLP morphology and its influential factors that are of critical importance to prevent and control gully erosion.

Study and application on the evaluation method of porous formation for long-term waterflooding sand reservoir

Nine targets which stand both for the static characteristic of produced formations and the dynamic parameter of wells including the average permeability,variation coefficient of permeability,moving capability,remaining recoverable reserves,coefficient of flooding,daily oil production,increasing rate of water cut,cumulative liquid production per unit meter and efficiency index of oil production are selected as the evaluation indexes,a novel model to evaluate the porous formations in long-term waterflooding sand reservoir was established by using the support vector machine and clustering analysis. Data of 57 wells from Shentuo 21 block Shengli oilfield was analyzed by using the model. Four kinds of formation groups were gained. According to the analysis result,different adjustment solutions were put forward to develop the relevant formations. The Monthly oil production increased 7.6 % and the water cut decreased 8.9 % after the adjusted solutions. Good results indicate that the learning from this method gained will be valuable adding to other long-term waterflooding sand reservoirs in Shengli oilfield and other similar reservoirs worldwide.

Influences of different time intervals between loop electrosurgical excision and abdominal hysterectomy or radical hysterectomy on postoperative complications: a retrospective analysis

Objective： To study the influences of different time intervals between loop electrosurgical excision （LEEP） and abdominal hysterectomy or radical hysterectomy on postoperative complications. Methods： Sixty-eight patients, who received subsequent abdominal hysterectomy or radical hysterectomy after LEEP due to C1N III and cervical cancer （IA1, IA2 and IB1）, were included in the present study. The hospital and clinic records of these patients were reviewed. The patients were divided into three groups according to the time intervals between LEEP and hysterectomy or radical hysterectomy： group l（within 48 h）, group 2 （between 48 h to 6 weeks）, and group 3（〉 6 weeks ）.Results： General characteristics of patients, including the mean age, delivery history, BMI, menopausal status, clinical stage and HPV infection, were comparable between patients of different groups. There were no significant differences in the mean transfusion amount, posthysterectomy hospital stay or operation time between different groups. The frequencies and spectrum of complications were not significantly affected by the time interval between LEEP and hysterectomy or radical hysterectomy. Conclusion： It is concluded that whenever the LEEP is done, the operation including hysterectomy or radical hysterectomy can be conducted at any time as it is necessary for the patients.

Depinning Dynamics of Fluid Monolayer on a Quenched Substrate

Langevin simulations are preformed on the depinning dynamics of fluid monolayer on a quenched substrate. With increase in the strength of the substrate, we find for the first time a crossover from elastic crystal to smectic flows as well as a crossover from smectic to plastic flows above the depinning. A power-law scaling relationship can be derived between the drift velocity and the driving force for both the elastic crystal and smectic flows, but fails to be obtained for the plastic flow. The power-law exponents are found to be no larger than 1 for the elastic crystal flow and larger than 1 for the smeetic flow. The critical driving force and the averaged intensity of Bragg peaks remain invariant basically in the regime of smectic flow. A sudden increase in the critical driving force is observed within the crossover from the smeetic to plastic flows, and the averaged intensity of Bragg peaks shows sudden decreases within the crossovers both from the elastic crystal to smectic flows and from the smectic to plastic flows. The results are helpful for understanding the slip dynamics of fluids on a molecular level.

Leptin and peroxisome proliferator-activated receptor γ expression in colorectal adenoma

AIM： To investigate the expressions of leptin and per- oxisome proliferator-activated receptor y （PPARG） in relation to body mass index （BMI）. METHODS： We evaluated leptin and PPARG expres- sion in 30 adenomas over 1 cm in size by immunohisto- chemical staining. In addition, clinicopathologic features including BMI were assessed. RESULTS： PPARG and leptin expression showed a strong positive correlation （P = 0.035）. The average BMI of the leptin-positive group was higher than that of the leptin-negative group （25.4 ＋ 3.4 kg/m2 vs 22.6 ＋ 2.4 kg/m2, P = 0.018）, and leptin expression was sig- nificantly correlated with high BMI （P = 0.024）. Leptinexpression was more frequently observed in intermedi- ate/high grade dysplasia than in low grade dysplasia （P = 0.030）. However, PPARG expression was not cor- related with BMI and grade of dysplasia. CONCLUSION： BMI has influenced on the leptin ex- pression of colorectal adenoma. The exact mechanism underlies the strong correlation between leptin and PPARG expression needs further study.

The mean value involving Dedekind sums and two-term exponential sums

In this paper,we use the analytic methods to study the mean value properties involving the classical Dedekind sums and two-term exponential sums,and give two sharper asymptotic formulae for it.

ORDERED WEIGHTED AVERAGING AGGREGATION METHOD FOR PORTFOLIO SELECTION

Portfolio management is a typical decision making problem under incomplete,sometimes unknown, information. This paper considers the portfolio selection problemsunder a general setting of uncertain states without probability. The investor's preferenceis based on his optimum degree about the nature, and his attitude can be described by anOrdered Weighted Averaging Aggregation function. We construct the OWA portfolio selection model, which is a nonlinear programming problem. The problem can be equivalentlytransformed into a mixed integer linear programming. A numerical example is given andthe solutions imply that the investor's strategies depend not only on his optimum degreebut also on his preference weight vector. The general game-theoretical portfolio selectionmethod, max-min method and competitive ratio method are all the special settings of thismodel.

Effects Of Average Index Variation in Apodized Long-Period Fiber Gratings

We analyze the effects of average index variation on the transmission characteristics of an index-apodized long-period fiber grating （LPFG） by the transfer matrix method and study how these effects depend on the grating length, the grating profile, the modal dispersion factor, and the duty cycle of the index modulation. Apart from shifting the resonance wavelength and modifying the rejection band, average index variation can give rise to significant side lobes that may appear on the short-wavelength or long-wavelength side of the rejection band, depending on the signs of the average index change and the modal dispersion factor. Our results provide general guidance for the writing of LPFGs for the minimization of side lobes. Our analysis compares well with published experimental results and should be useful for the design and fabrication of LPFGs.

THE GOLDBACH-VINOGRDOV THEOREM WITH THREE PRIMES IN A THIN SUBSET

It is proved constructively that there exists a thin subset S of primes, satisfying for some absolute constant c＞0, such that every sufficiently large odd integer N can beLet r be prime, and hi positive integers with (bj, r) = 1,j = 1, 2, 3. It is also proved that, for almost all prime moduli r＜ log- N, every sufficiently large odd integer N = b1 + b2 +ba(modr) can be represented as where c ＞ 0 is an absolute constant.

LIFE DISTRIBUTION OF SERIES UNDER THE SUCCESSIVE DAMAGE MODEL

We analyse further the reliability behaviour of series and parallel systems in the successive damage model initiated by Downton. The results are compared with those obtained for other models with different bivariate distributions.