二元Hamming码Ham(r,2)及其对偶码的性质研究

Hamming码Ham(r,q)作为一种完备的线形分组码,具有许多良好的性质,并且其译码方法非常简洁有效。在此基础上,对二元Hamming码Ham(r,2)及对偶码进行了进一步的研究,讨论了其对偶码所具有的几个性质。     

高维Mobius群的初等子群

研究了４ 种高维 Ｍｏｂｉｕｓ 群的初等子群定义之间的关系⒚得到了高维 Ｍｏｂｉｕｓ 群是初等群的充要条件；在离散的条件下，给出了这种初等子群的结构性定理⒚     

具非整数滞后的不确定性线性定常离散控制系统的鲁棒镇定

应用频率等价法研究了一类非整数滞后不确定性线性定常离散控制系统的鲁棒镇定问题，给出了该系统鲁棒镇定的估计公式．     

Nutrient cycling in two traditional Central American agroforestry systems

A preliminary nutrient cycling study quantified total and temporal nutrient inputs via litterfall and pruning residues in two agroforestry systems: (1) Coffea arabica (perennial crop)-Erythrina poeppigiana (leguminous shade tree); and (2) C. arabica-E. poeppigiana-Cordia alliodora with emphasis on the effect of the timber tree C. alliodora. The total annual input of litterfall plus pruning residues was similar in both associations. Total annual input from E. poeppigiana was less than half in the association with C. alliodora than without, but the litterfall from this latter species compensated for the loss. Large differences in the total annual nutrient input of K, Ca and Mg was found between associations, but not for N or P. The amount of nutrients recycled by the associated trees reached the recommended level of fertilizer required for coffee production. The inclusion of C. alliodora within the C. arabica-E. poeppigiana association resulted in a more evenly distributed annual nutrient input.     

《天净沙·秋思》英译本之我见——与黄国文、金春笙先生商榷

《中国翻译》上刊登了黄国文和金春笙先生对《天净沙.秋思》英译本的分析和研究。针对金先生和黄先生相驳的两种观点,文章首先从语言学角度审视了“形式对等”的真正内涵、实用性以及可接受性;然后从文学角度——音律、情感逻辑、意象虚实等来探讨《天净沙.秋思》的Schlepp和翁显良两种英译本孰优孰劣;最后建议运用语言学的分析方法来理性思考,结合文学的印象式、感悟式和经验式的翻译批评可以使得译文更富艺术魅力。     

The Storage of Tree Data Structure by Gradation and Classification and Application in CAD for Engineering Structure

The traditional storage of tree data structure is according to the relation of the elements' frant-and-back. Since it is difficult to define the frant-and-back relation of graphics units in CAD for Engineering structure, the application of the tree structure becomes inconvenient. The authors change the storing method for the tree structure into gradation and classification. And a graded equivalence relation of graphics units is brought forward, which grade the graphics units with the equivalence relation. By using this storing method, we can easily accomplish some operations, such as picking up the subtree with a certain character, deleting a node, insert a graded and classified node, etc. The example provided indicates that the storage by gradation and classification can speed up searching and process the data of the subtree by gradation and classification expediently. This kind of storing method for the tree structure is applicable for data which contain the graded equivalence relation.     

猪粪氮素有效性与替代化肥氮当量研究

采用温室盆栽试验,初步研究了猪粪氮素的有效性和替代氮肥的替代当量,并结合田间试验对等有效氮条件下有机无机配施与单施化肥的效果进行了比较。盆栽试验表明,随着猪粪用量的增加,氮素回收率逐渐降低,回收率为22.5%～38.3%,平均30.6%。当猪粪用量为N 120 mg/kg时,其氮素相对于化肥的相对有效性为27%。不同用量下猪粪的替代氮肥当量也具有一定差异,相对替代当量为24.0%～40.8%,平均32.9%。田间试验表明,利用猪粪中的有效氮替代30%的化肥氮对春玉米干物质和籽粒产量以及氮素吸收量没有影响,与100%化肥氮处理相当。     

文体翻译对等的量化评估

文体对等是翻译过程中所要求达到对等的一个层面。本文通过统计正负文体成分在语篇中的比值,来量化评估译文与原文在文体上是否对等,通过实例评估取得了较为满意的结果,为量化评估译文质量开辟了一条道路。     

Effect of calf death loss on cloned cattle herd derived from somatic cell nuclear transfer: Clones with congenital defects would be removed by the death loss

To increase public understanding on cloned cattle derived from somatic cell nuclear transfer (SCNT), the present review describes the effect of calf death loss on an SCNT cattle herd. The incidence of death loss in SCNT cattle surviving more than 200 days reached the same level as that in conventionally bred cattle. This process could be considered as removal of SCNT cattle with congenital defects caused by calf death loss. As a result of comparative studies of SCNT cattle and conventionally bred cattle, the substantial equivalences in animal health status, milk and meat productive performance have been confirmed. Both sexes of SCNT cattle surviving to adulthood were fertile and their reproductive performance, including efficiency of progeny production, was the same as that in conventionally bred cattle. The presence of substantial equivalence between their progeny and conventionally bred cattle also existed. Despite these scientific findings, the commercial use of food products derived from SCNT cattle and their progeny has not been allowed by governments for reasons including the lack of public acceptance of these products and the low efficiency of animal SCNT. To overcome this situation, communication of the low risk of SCNT technology and research to improve SCNT efficiency are required.     

玉米秸秆循环流化床气化炉气化工艺参数优化

为实现秸秆类农业生物质废弃物的高效清洁能源化转化利用,采用带有二级返料系统的循环流化床气化炉对玉米秸秆进行了气化试验。在二级返料系统开启及闭合条件下,选取空气当量比为0.20～0.35,研究空气当量比对玉米秸秆气化特性的影响,结果表明二级返料系统开启及闭合两种工况均在空气当量比为0.26时取得较优值,二级返料系统开启时具有较好的气化效果,碳转化率与气化效率最大值分别达到93.54%与77.06%。在二级返料系统开启状态下,试验研究了水蒸气配比对玉米秸秆气化特性的影响,结果表明以空气为主气化介质,辅助以水蒸气气化,可以有效改善气化燃气品质,提升气化效率。当空气当量比为0.26、水蒸气配比为0.2时,玉米秸秆空气—水蒸气气化具有较好的气化特性,燃气热值与气化效率分别达到最大值5.89MJ/m3与81.45%。典型工况条件下的焦油蒸馏馏分分析结果表明,提高气化炉反应温度,并保持一定的水蒸气气化环境,可促进焦油裂解转化。试验可为秸秆类生物质的高效清洁转化利用提供参考依据。