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排序方式: 共有372条查询结果,搜索用时 31 毫秒
111.
In this paper, we propose new quantum arithmetic protocols among multiple parties. Let some parties have values. A problem is to find a protocol such that under the condition that any eavesdropper intercepting any quantum system being exchanged among the parties must not be able to acquire information, the parties compute an arithmetic operation such as addition and multiplication, and transfer its computing result to another party. One of main ideas to solve this problem is based on operating state phases. A quantum addition algorithm based on operating phases has been proposed by Draper, but his algorithm was not considered being eavesdropped. We propose secure quantum arithmetic protocols. 相似文献
112.
The Australian Fiberscopic Profile (AFP) was developed for use in a previous study of normal voices to provide standard documentation for examining the larynx under continuous light. The AFP is being used currently in five specialized voice clinics in Australia to collect data on dysphonic voices. After use with 40 clients it became obvious that a revision with clearer definitions of the parameters was needed to make it a more useful clinical tool. 相似文献
113.
利用Nd~(3+):YAG主被动锁模加晶体管雪崩吸收单选,再放大、倍频、混频,产生30ps,355nm激光单脉冲,用它泵浦Ⅱ类非临界相应匹配的LiB_3O_5光参量发生器,在精密温度控制下,获得415.9~482.6nm的蓝紫光可调谐输出,线宽0.15nm,最高参量转换效率37.6%,可输出能量为6.33mJ,峰值功率为211MW的皮秒激光单脉冲. 相似文献
114.
115.
通过引入基于身份(Identity-based)的公钥密码体制,提出了一个基于身份的802.11无线局域网安全认证结构.文中详细描述了从初步建立系统参数,动态的共享密钥的生成,到4-way握手的相互身份认证的认证协议过程以及Weil Palring的实现,并且通过上海交通大学无线网络测试,说明了该协议在安全性方面和实际应用中相对于目前的无线局域网安全协议的优越性. 相似文献
116.
117.
提出了一种描述和构造通讯设备或通讯介质的Petri网模型,以该模型为基础给出了一个设计网络的Petri网模型的方法,并且给出了一个使用该方法构造的Petri网模型的性能测试实例,为网络设计和网络性能分析提供了一种新的参考方法。 相似文献
118.
Pedro Rosario José Luis Martínez José Miguel Silván 《Accreditation and quality assurance》2008,13(9):493-499
In analytical chemistry, proficiency testing usually consists in tests that laboratories conduct under routine conditions
and report the result to the PT provider who then converts the result to a score which helps the participant to assess the
accuracy of the result. The aim of this work is to show PT providers, accreditations bodies, and participating laboratories
that different scoring results can be achieved depending on the evaluation system selected. The influence of different evaluation
techniques on the results of an interlaboratory comparison for determination of gold in precious metals alloys was investigated.
Results from 19 participating laboratories were evaluated by means of the three procedures: (1) classical statistical approach—outliers
detection; (2) robust methods—(2A) robust procedure and (2B) ISO 13528; and (3) fitness for purpose. Evaluation of the same
PT data revealed very interesting issues depending on the different scoring systems that were used and the robustness of the
statistical methods used for detecting outliers. As a general rule, laboratories with scoring Z > 2 offered clearly poorer performance in robust approaches than classical ones. In order to support this first evidence,
we evaluated a second data set with results from 24 laboratories (mercury from soil samples) by means of the four mentioned
approaches. Selection and comparison of different scoring systems must be done very carefully, because sometimes they are
not the best approach for studying the data population or the more appropriate one for evaluating the distribution of the
data. Finally it should be taken into account that sometimes the robust scoring systems are not always suitable for evaluating
the results of some PT schemes. 相似文献
119.
Diana C. Vinueza-Espinosa Daniel R. Cuesta-Aguirre Assumpció Malgosa Cristina Santos 《Electrophoresis》2023,44(17-18):1423-1434
Poor nuclear DNA preservation from highly degraded skeletal remains is the most limiting factor for the genetic identification of individuals. Mitochondrial DNA (mtDNA) typing, and especially of the control region (CR), using next-generation sequencing (NGS), enables retrieval of valuable genetic information in forensic contexts where highly degraded human skeletal remains are the only source of genetic material. Currently, NGS commercial kits can type all mtDNA-CR in fewer steps than the conventional Sanger technique. The PowerSeq CRM Nested System kit (Promega Corporation) employs a nested multiplex-polymerase chain reaction (PCR) strategy to amplify and index all mtDNA-CR in a single reaction. Our study analyzes the success of mtDNA-CR typing of highly degraded human skeletons using the PowerSeq CRM Nested System kit. We used samples from 41 individuals from different time periods to test three protocols (M1, M2, and M3) based on modifications of PCR conditions. To analyze the detected variants, two bioinformatic procedures were compared: an in-house pipeline and the GeneMarker HTS software. The results showed that many samples were not analyzed when the standard protocol (M1) was used. In contrast, the M3 protocol, which includes 35 PCR cycles and longer denaturation and extension steps, successfully recovered the mtDNA-CR from highly degraded skeletal samples. Mixed base profiles and the percentage of damaged reads were both indicators of possible contamination and can provide better results if used together. Furthermore, our freely available in-house pipeline can provide variants concordant with the forensic software. 相似文献
120.
为了应对降雨给采用诱骗态协议的量子通信系统带来的突发性干扰,根据降雨分布模型和退极化信道的特性,本文提出了基于变色龙算法的每脉冲最优平均光子数自适应策略;建立了降雨强度、链路距离与最优平均光子数之间的自适应关系;并对采用变色龙算法前后,系统的性能参数进行了比较.仿真结果表明,当降雨强度J为30 mm/24 h、链路距离L为30 km时,通过采用变色龙算法,系统的安全密钥生成率由2×10~(-4)提高到3.5×10~(-4);当J为60 mm/24 h,L为20 km时,系统的信道生存函数值由0.52提高到0.63;当要求生存函数不低于0.5时,系统能够应对的最大雨强由62 mm/24 h提高到74 mm/24 h.因此,根据降雨强度和链路距离,通过变色龙算法自适应地调整系统发送端信号脉冲所含的平均光子数,可以提高量子通信系统在降雨背景下的有效性和可靠性. 相似文献