明清以来江南蚕桑区叶市上的远期交易

明清以来江南地区湖州、嘉兴等蚕桑区叶市上的"稍叶"交易,是一种典型且成熟的远期交易。叶市交易的对象——桑叶,其新鲜程度的要求极高,供给与需求的不确定性较大,且交易时间集中而短暂,这使得叶市呈现出高风险,尤其是高价格风险的特性。远期交易方式的采用,是一种规避市场风险的制度安排,它有着一套成熟的运作机制,湖州、嘉兴等地一些市镇上叶行的营业,对于这种远期交易方式的组织和实现,起着关键性的作用。虽然有大量投机现象的存在,但总的来说,以远期交易为显著特征的江南叶市在相当长的时期内维持了较好的信用状况。江南叶市远期交易,反映了这一地区市场的成熟已达到相当高的程度,对于正确认识传统江南经济的发展状况有着重要参考价值。

明清时期江南清明卜叶习俗与桑叶市场

明清时期,江南蚕桑区普遍存在着清明占卜叶事的习俗,蚕桑户通过各种方式占卜当年桑叶丰歉、叶价高低。这一习俗的形成与传播是当地蚕桑生产兴盛的折射。随着蚕桑生产的规模化、专业化、商品化进程,江南桑叶市场不断发展,并涌现出一批专门交易桑叶的特色市镇。叶市价格剧烈波动的特性,让种桑、养蚕的农户以及专事桑叶贸易的经营者都承担着很大的经济风险。作为蚕桑生产的主要劳动力,女性成为经济风险的主要承担者。卜叶正是为了缓释这种风险和压力而产生的民俗事象。这类习俗既反映了农户希望借助超自然力量消灾祈福的心理,也指导着农户调整蚕桑生产规模,推进了江南蚕桑生产发展。

Impact of correlated private signals on continuous-time insider trading

A model of continuous-time insider trading in which a risk-neutral in-sider possesses two imperfect correlated signals of a risky asset is studied.By conditional expectation theory and filtering theory,we first establish three lemmas:normal corre-lation,equivalent pricing and equivalent profit,which can guarantee to turn our model into a model with insider knowing full information.Then we investigate the impact of the two correlated signals on the market equilibrium consisting of optimal insider trading strategy and semi-strong pricing rule.It shows that in the equilibrium,(1)the market depth is constant over time;(2)if the two noisy signals are not linerly correlated,then all private information of the insider is incorporated into prices in the end while the whole information on the asset value can not incorporated into prices in the end;(3)if the two noisy signals are linear correlated such that the insider can infer the whole information of the asset value,then our model turns into a model with insider knowing full information;(4)if the two noisy signals are the same then the total ex ant profit of the insider is increasing with the noise decreasing,while down to O as the noise going up to infinity;(5)if the two noisy signals are not linear correlated then with one noisy signal fixed,the total ex ante profit of the insider is single-peaked with a unique minimum with respect to the other noisy signal value,and furthermore as the noisy value going to O it gets its maximum,the profit in the case that the real value is observed.

An Oracle-based Data Management Method for Large Database in CyberCity GIS

An Oracle8i-based approach is proposed to manage the integrated databases oflarge CyberCity. This approach consists of three schemes: ① a special R+-tree index is designed toaccelerate spatial retrieving, in which the bounding boxes of local regions have no intersection andall leaf nodes of the R+-tree (geometry records ) have no repetition; ② different data compressionalgorithms are adopted to compress the digital elevation models, 3D vector models and images, suchas LZ77 lossless compression algorithm for compression of vector data and JPEG compressionalgorithms for texture images; ③ in order to communicate with Oracle8i database, a CyberCity GIS.spatial database engine (SDE) is designed. On the basis of this SDE prototype a case study is done.

Magnetic Properties of Tree Leaves and Their Significance in Atmospheric Particle Pollution in Linfen City,China

Fifty-one tree leaves were sampled in the industrial area,residential area,and Fenhe River ecological zone,for the purpose of a magnetic study on atmospheric pollution in Linfen City,Shanxi Province,China.Measurements of mass-specific magnetic susceptibility(χ) show a significant variation range(from 11.6 × 10-8 m3/kg to 129.7 × 10-8 m3/kg).Overall values of magnetic susceptibility decline in the following sequence:industrial area > residential area > Fenhe River ecological zone.The relatively elevated concentration-related magnetic parameters(saturation isothermal remanent magnetization,anhysteretic remanent magnetization and magnetic susceptibility) appear in the industrial area,with their highest values in the vicinity of Linfen Steel Mill.Magnetic particles are dominated by multidomain,magnetite-like minerals.Magnetic particle concentration and grain size both decrease with the increasing distance from industrial area,indicating the industrial area,especially Linfen Steel Mill,is the main source of atmospheric particle pollution.Residential area and Fenhe River ecological zone are also affected by industrial emission to a certain extent.The results of this study indicate that magnetic measurements of tree leaves are practicable for monitoring and determination of atmospheric pollution in Linfen City.

Studies on Material Cycling in Evergreen Broad-Leaved Forest Ecosystem in Hangzhou: Ⅰ. Precipitation Distribution

Through the long-term plot studies on the precipitation distribution in the evergreen broad-leaved forest ecosystem in Hangzhou for two years, it was indicated that the pattern of precipitation distribution included larger amounts of penetration water and stemflow and a lower amount of interception water. The results revealed that the main factors to infulence the percentages of penetration and stemflow were the air temperature and the leaf area of the forest. The quantity of seepage through the litter layer was much larger than that through the soil layers which decreased sharply with soil depth. The output of water from the ecosystem by surface runoff and deep infiltration through the soil was much lower, only being 5.20 percent of the rainfall, while the water evapotranspiration loss was as large as more than 90 percent of it. The losses by the soil evaporation and plant evapotranspiration were the largest part of output in this forest ecosystem.

Mechanism of high concentration phosphorus wastewater treated by municipal solid waste incineration fly ash

The mechanism of removing phosphate by MSWI(municipal solid waste incineration)fly ash was investigated by SEM(scanning electron microscopy)with EDS(energy dispersion spectrum),XRD(X-ray diffraction),FT-IR(Fourier transform infrared spectroscopy),BET(specific surface area),and BJH(pore size distribution).The results indicate that the removal rate of phosphate(100 mg/L)in 50 mL phosphorus wastewater reaches at 99.9% as the dosage of MSWI fly ash being 0.9000 g under room temperature.The specific surface area of MSWI fly ash is less than 6.1 m2/g and the total pore volume is below 0.021 cm3/g,suggesting that the absorption capacity of calcite is too weak to play an important role in phosphate removal.SEM images show that drastic changes had taken place on its specific surface shape after reaction,and EDS tests indicate that some phosphate precipitates are formed and attached onto MSWI fly ash particles.Chemical precipitation is the main manner of phosphate removal and the main reaction is: 3Ca2++2 PO4 3-+xH2O→Ca3(PO4)2↓·xH2O.Besides,XRD tests show that the composition of MSWI fly ash is complex,but CaSO4 is likely to be the main source of Ca2+.The soluble heavy metals in MSWI fly ash are stabilized by phosphate.

Sectoral Agglomeration and Urban Development： The History of Tunxi--The Tea Business Centre in Huizhou

From the perspective of historical geography, Tunxi as the chosen centre for tea production in the Qing could not be explained geographically alone by the river system of Huizhou, in which stead this article attempts a historicogeographical analysis by shifting our attention towards the sector-specific agglomeration of rel- evant industries and urbanisation. Due to the restrictions by the imperial government on using sea ports （e.g. Shanghai） for the transportation of tea south- wards for sale and export, Tunxi was made the centre for tea trade, not only due to its geographical convenience to tax clearance, but also because of the agglomeration of tea-related industries in the City, such as tin-can, box and bamboo-crate ware- houses. There also had emerged in this process a conglomeration of daily life services, making Tunxi a place of convenience-cure-prosperity. Thus, a combination of both historical and geographical factors can help in no small way to offer a better explanation of the urban development of Tunxi as a tea trade centre in imperial China.

Analysis of plant remains at the Neolithic Yangjia Site, Wuxi City, Jiangsu Province (East China)

According to archaeological investigation and preliminary excavation, the Yangjia Site, located in the northern Taihu Lake region, at Wuxi City, Jiangsu Province, is a Neolithic archaeological site dominated by cultural remains attributed to the late Majiabang Culture(6270–5920 cal. a BP). Here a systematic archaeobotanical study was conducted to investigate vegetation landscape, environmental characteristics and rice agriculture in the prehistoric northern Taihu Lake area. The abundance, frequency and standard density of charred rice were the highest of all of the remains of the seed plants unearthed. In addition, a variety of wetland weeds, such as Haloragaceae, Cyperaceae, Carex sp., and Oxalis corniculata, were found. Pollen and phytoliths recorded that the evergreen-deciduous broadleaf mixed forest(represented by Quercus and Castanopsis) tends to decrease, while Poaceae was the most significant of the terrestrial herbs, water area expanded and water activities strengthened, indicating generally warm and humid conditions at the Yangjia Site during the late Majiabang Culture. All indicators of pollen, phytolith and macro-plant remains suggest that wild rice should be once distributed at or around the site before human occupation, after which rice agriculture progressed rapidly during the late Majiabang Culture.

PRICING CONVERTIBLE BONDS AND CHANGE OF PROBABILITY MEASURE

The changes of numeraire can be used as a very powerful tool in pricing contingent claims in the context of a complete market.By using the method of numeraire changes to evaluate convertible bonds when the value of firm,and those of zero-coupon bonds follow general adapted stochastic processes in this paper,using Ito theorem and Gisanov theorem.A closed-form solution is derived under the stochastic volatility by using fast Fourier transforms.