长江下游陆生等足目的研究（Ⅱ）：南京陆生等足目记述

记述了采自南京陆生等足目，共７种，隶属４科４属，其中南京球形虫（Ｓｐｈｅｒｉｌｌｏｎａｎｊｉｎｅｎｓｉｓｓｐ．ｎｏｖ．）和老山气肢虫（Ｔｒａｃｈｅｌｉｐｕｓｌａｏｓｈａｎｅｎｓｉｓｓｐ．ｎｏｖ．）为新种，美丽卷甲虫（ＡｒｍａｄｉｌｌｉｄｉｕｍｐｉｃｔｕｍＢｒａｎｄｔ，１８３３）为新记录种．并对新种、新记录种的分类特征、生态习性作了描述和讨论．     

中国典型地带陆生等足类的区系特点

通过对中国5个典型地带（热带、亚热带、暖温带、温带和高寒带）20个样点采集的72种陆生等足类的区系进行分析,发现具有以下特点：1.分布的地带性强,特有种多;2.东洋界热带,亚热带区系占主导地位;3.物种栖息生境多样;4.与日本区系进行比较发现其种级阶元的差异较大,其中在我国72种陆生等足类中有61种与日本不同,占总种数的84.7%.表明种类分布上具有极强的区系差别.     

Al-Zn-In-Ga-Si牺牲阳极合金在地热水中的电化学性能研究

对自行研制的Al-3.5wt% Zn -0.02 wt% In- 0.02 wt% Ga-0.15 wt%Si牺牲阳极合金在不同温度地热水中的电化学性能进行了测试研究,为地热井完井筛管的电化学保护提供了设计计算依据。     

Current status of an amphipod invader,Arcitalitrus dorrieni (Hunt, 1925), in Britain

The synanthropic landhopper Arcitalitrus dorrieni (Hunt) is largely restricted to the south-west of Britain although there are isolated populations outside this area. It has been recorded from 60 new 10-km squares since Harding and Sutton (1988 Harding, P. T and Sutton, S. L. 1988. The spread of the terrestrial amphipod Arcitalitrus dorrieni in Britain and Ireland: watch this niche!. Isopoda, 2: 7–10.  [Google Scholar]) last reviewed its distribution. Some of the new records, particularly in south Wales, could be interpreted as meaning that there has been range expansion in this time. However, the evidence is equivocal. It was not possible to explain the distribution of A. dorrieni in terms of association with native plant species. The main means of dispersal still seems to be synanthropic. Arcitalitrus dorrieni has retained a mainly coastal distribution, with penetration inland restricted to peninsular areas (with some notable exceptions, e.g. populations in London).     

Revision of the smiling worms,genera Prosadenoporus Bürger, 1890 and Pantinonemertes Moore and Gibson, 1981 and description of a new species Prosadenoporus floridensis sp. nov. (Prosorhochmidae; Hoplonemertea; Nemertea) from Florida and Belize

The hoplonemertean genera Prosadenoporus Bürger, 1890 Bürger, O. 1890. Untersuchungen über die anatomie und histologie der nemertinen nebst beiträgen zur systematik [Studies of anatomy and histology of nemerteans with contribution to systematics].. Z Wiss Zool., 50: 1–277. German [Google Scholar] and Pantinonemertes Moore and Gibson, 1981 Moore, J. and Gibson, R. 1981. The Geonemertes problem (Nemertea).. J Zool., 194: 175–201.  [Google Scholar] are revised and synonymized based on a morphological re‐evaluation. We redefine Prosadenoporus Bürger, 1890 Bürger, O. 1890. Untersuchungen über die anatomie und histologie der nemertinen nebst beiträgen zur systematik [Studies of anatomy and histology of nemerteans with contribution to systematics].. Z Wiss Zool., 50: 1–277. German [Google Scholar] on the basis of characters held in common by the eight species: Prosadenoporus agricola (Willemoes‐Suhm, 1874 Willemoes‐Suhm, R. 1874. On a land‐nemertean found in the Bermudas.. Ann Mag Nat Hist. Ser 4., 13: 409–411.  [Google Scholar]) comb. nov., Prosadenoporus arenarius Bürger, 1890 Bürger, O. 1890. Untersuchungen über die anatomie und histologie der nemertinen nebst beiträgen zur systematik [Studies of anatomy and histology of nemerteans with contribution to systematics].. Z Wiss Zool., 50: 1–277. German [Google Scholar], Prosadenoporus spectaculum (Yamaoka, 1940 Yamaoka, T. 1940. Two nemerteans from the Riukiu Islands.. Annot Zool Japon., 19: 13–18.  [Google Scholar]) comb. nov., Prosadenoporus winsori (Moore and Gibson, 1981 Moore, J. and Gibson, R. 1981. The Geonemertes problem (Nemertea).. J Zool., 194: 175–201.  [Google Scholar]) comb. nov., Prosadenoporus enalios (Moore and Gibson, 1981 Moore, J. and Gibson, R. 1981. The Geonemertes problem (Nemertea).. J Zool., 194: 175–201.  [Google Scholar]) comb. nov., Prosadenoporus mooreae (Gibson, 1982b Gibson, R. 1982b. Nemerteans of the Great Barrier Reef. 5. Enopla Hoplonemertea (Monostilifera).. Zool J Linn Soc., 75: 269–296.  [Google Scholar]) comb. nov., Prosadenoporus mortoni (Gibson, 1990 Gibson, R. 1990. “The macrobenthic nemertean fauna of Hong Kong.”. In The Marine Flora and Fauna of Hong Kong and Southern China, Edited by: Morton, B. 33–212. Hong Kong: Hong Kong University Press.  [Google Scholar]) comb. nov. and Prosadenoporus fujianensis (Sun, 2001 Sun, S. 2001. A new mangrove‐dwelling nemertean from China.. Hydrobiologia, 456: 199–209.  [Google Scholar]) comb. nov. We describe a new semi‐terrestrial species Prosadenoporus floridensis sp. nov. from Belize and Florida and compare its morphology to other species of Prosadenoporus. The average sequence divergence of P. floridensis sp. nov. from other congeners is 9.15% (16S) and 10.65% (COI) and 7.8% and 10.3% respectively from the nearest sequenced congener P. mortoni.     

TDS-OFDM系统中的差分空频发射分集方法

在采用相干检测方法的发射分集方案中,进行信道估计需要付出很高的代价,为了降低接收端的实现复杂度,根据时域同步正交频分复用(TDS-OFDM)系统结构的特点,提出了差分空频发射分集及相应的非相干检测方法。该方法在时域进行差分编码,而在频域进行空频编码以获得分集增益。理论分析和仿真结果表明,尽管非相干检测方法损失了一定的接收性能,但无需进行信道估计,在慢衰落和快衰落信道中均能适用,是一种比较好的实现复杂度与接收性能之间的折衷方法。     

地面三维激光扫描点云配准的最佳距离

分析点云配准的原理,在此基础上推导出点云配准误差传播模型.利用该模型解算了配准后的点位误差,将该误差作为衡量点云配准好坏的指标.为评估地面三维激光扫描测距的变化给点云配准误差造成的影响,设计了一套试验方案,在地面三维激光扫描仪测距精度内对不同距离进行了严格的试验.根据提取的靶心和点云配准误差传播模型,计算得出不同距离下的点云配准精度,从而分析得出点云配准精度的扫描最佳距离.结果表明点云误差传播模型正确,试验方法良好.     

Rediscovery of the southern California endemic American Keeled Slug Anadenulus cockerelli (Hemphill, 1890) after a 68-year hiatus

ABSTRACT

We report the first records of the southern California endemic American Keeled Slug Anadenulus cockerelli (Hemphill, 1890) in 68 years. Due to the restricted range of this species and lack of recent detection, it has received a NatureServe conservation status of Critically Imperilled or Imperilled. This species has always been difficult to detect, and will likely continue to be. This may be the result of genuine rarity, or may be the result of being cryptic and occurring in a microhabitat only ephemerally accessible to humans. We created a Species Distribution Model for A. cockerelli, which strongly predicts its occurrence where it is known, as well as some locations where it is currently unknown, such as in the northern Peninsular Ranges and in the San Bernardino Mountains in California. Threats to the continued existence of this species in southern California include human encroachment and resulting habitat loss, the climate changing to be hotter and drier, increased fire frequency, oak death due to beetle infestation, and other introduced species. Anadenulus cockerelli should continue to be surveyed and monitored into the future in order to better understand its distribution and level of conservation concern.     

基于PTS级联抵消的峰均比抑制性能仿真

提出了PTS级联抵消算法,实现对地面数字多媒体广播系统中时域同步正交频分复用信号的峰均功率比的抑制.通过研究地面数字多媒体广播系统传输协议,分析了采用时域同步正交频分复用多载波调制方式对系统射频前端信号时域性能的影响.针对信号峰均功率比高的缺陷,提出一种新颖的峰值功率比抑制算法.该算法对峰均功率比的抑制能力强于传统PTS算法,引起的带外辐射和互调失真小于传统限幅技术.当子载波数较大时,仍可实现对系统峰均功率比的有效控制.通过仿真,与传统限幅技术相比,算法可以使地面数字多媒体广播系统的峰均功率比控制在4-5dB,比传统PTS算法峰均功率比减小约3-4dB,且仅有少量的误码率性能损失.