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Control of Wave Propagation and Effect of Kerr Nonlinearity on Group Index 被引量:1
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作者 Hazrat Ali Ziauddin Iftikhar Ahmed 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第7期87-92,共6页
We use four-level atomic system and control the wave propagation via forbidden decay rate. The Raman gain process becomes dominant on electromagnetically induced transparency (EIT) medium by increasing the forbidden d... We use four-level atomic system and control the wave propagation via forbidden decay rate. The Raman gain process becomes dominant on electromagnetically induced transparency (EIT) medium by increasing the forbidden decay rate via increasing the number of atoms [G.S. Agarwal and T.N. Dey, Phys. Rev. A 74 (2005) 043805 and K. Harada, T. Kanbashi, and M. Mitsunaga, Phys. Rev. A 73 (2006) 013803]. The behavior of wave propagation is dramatically changed from normal (subluminal) to anomalous (superluminal) dispersion by increasing the forbidden decay rate. The system can also give a control over the group velocity of the light propagating through the medium via Kerr field. 展开更多
关键词 normal and anomalous dispersion Kerr field group index
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High Differential Group Index of Dispersion Compensating Fibers for OCDMA Encoder/Decoder
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作者 Tae-Jung Eom Chang-Soo Park +2 位作者 Un-Chul Paek Byeong Ha Lee Taesang Park 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期221-222,共2页
We report the LPG pair device that can be used as a pulse duplicator or an OCDMA encoder/decoder. Due to the ring core region of dispersion compensating fiber (DCF), we can shorten the device length by a third and obt... We report the LPG pair device that can be used as a pulse duplicator or an OCDMA encoder/decoder. Due to the ring core region of dispersion compensating fiber (DCF), we can shorten the device length by a third and obtain surrounding insensitive LPG devices. 展开更多
关键词 OCDMA BE in on DCF High Differential group index of Dispersion Compensating Fibers for OCDMA Encoder/Decoder mode of for
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Quantitative Correlation between Group Connectivity Index and Property of Flotation Reagent 被引量:2
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作者 Cao, YC Jiang, YR +1 位作者 Xue, YL Wang, DZ 《Journal of Central South University》 SCIE EI CAS 2000年第1期25-28,共4页
Topological method is applied firstly to calculate the group connectivity indexes of some flotation reagents for sulfide minerals and oxide minerals. The study reveals that some properties of flotation reagents, such ... Topological method is applied firstly to calculate the group connectivity indexes of some flotation reagents for sulfide minerals and oxide minerals. The study reveals that some properties of flotation reagents, such as group electronegativity, energy criterion, solubility product of chemicals and maximum wavelength of ultraviolet absorbency, have linear correlation with the first order group connectivity index (GCI) of polar group, and the related coefficients are all larger than 0.900. The GCI can be used to characterize the structure of groups, and is a sort of new effective structural parameter to study the quantitative structure activity relationship of flotation reagents. 展开更多
关键词 FLOTATION REAGENTS group connectivity index PROPERTY QUANTITATIVE CORRELATION
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Early Cretaceous Climate Changes Recorded in Magnetic Susceptibility and Color Index Variations of the Lower Liupanshan Group, Central China 被引量:3
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作者 DAI Shuang ZHU Qiang +9 位作者 HUANG Yongbo DA SILVA Anne-Christine ZHAO Jie LIU Junwei KONG Li PENG Dongxiang LUO Lingling YAN Ningyun WANG Wenjie ZHANG Xiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期1011-1023,共13页
This study carried out comprehensive analysis on sedimentology, magnetic susceptibility (7of) and color data of the continental sediments of the Liupanshan Group in Central China so as to obtain climatic change info... This study carried out comprehensive analysis on sedimentology, magnetic susceptibility (7of) and color data of the continental sediments of the Liupanshan Group in Central China so as to obtain climatic change information during the 129.14-122.98 Ma interval. Based on the results of the Xlf and of the redness (a*), the section can be divided into two segments: (1) 129.14-126.3 Ma, with the lowest Xlf values and strongly variable relatively high values of redness and (2) 126.3-122.98 Ma, with high Elf values and relatively low redness. Analysis of the lithology and facies as well as the magnetic minerals and their contents points to a detrital origin of the magnetic minerals and this allow us to interpret the relationship between magnetic susceptibility variations and climate changes. Our study shows that the climate was significantly dry and hot during the whole studied interval although the interval between 126.3 Ma and 122.98 was a little bit cooler with increased humidity. 展开更多
关键词 magnetic susceptibility color index climate change Liupanshan group Early Cretaceous
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The Impact of Salivary pH Value and Dental Caries Index on Periodontal Status among Adult Age Groups of Patients from Aseer Region, Saudi Arabia
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作者 Mohammed M. A. Abdullah Al-Abdaly Abdalkarim Ibrahim Mohammed Assiry 《Open Journal of Stomatology》 2020年第7期199-209,共11页
<b><span>Background:</span></b><span> The patients’ age is considered a modified risk factor that causes periodontal disease, dental caries, and their development.</span><b... <b><span>Background:</span></b><span> The patients’ age is considered a modified risk factor that causes periodontal disease, dental caries, and their development.</span><b><span> Objective:</span></b><span> The present study was designed to evaluate the impact of salivary pH value and dental caries index on periodontal status among adult age groups of patients from Aseer region, Saudi Arabia</span><span>.</span><span> </span><b><span>Methods:</span></b><span> A cross-sectional analysi</span><span>s carried out in the college of dentistry, King Khalid University on 750 </span><span>adult patients (400 males and 350 females). The adults patients were divided into three equal groups according to the patients’ age: group I (20 - 30 years), group I</span><span>I (31 - 40 years), and group III (41 - 50 years).</span><span> </span><span>Plaque index (PLI), gingi</span><span>val index (GI), clinical attachment loss (CAL), and the dental caries index (DMFT)</span><span> recorded as w</span><span>ell as salivary pH. All findings collected, then analyzed by an</span><span> ANOVA test and the t</span><span>-test. A p-value at <0.05 was considered a statistical significance level.</span><span> </span><b><span>R</span></b><b><span>esults:</span></b><b><span> </span></b><span>The clinical findings of the current study showed that there were statistically significant differences in the patients’ age of both males and females. Moreover, there were statistically significant diffe</span><span>rences in GI. On the other hand, there were highly statistically significant differences in PLI and DMFS, but there were no significant differences</span><span> in CAL of both males and females </span><span>Moreover, there were no statistically significant differences in salivary pH</span><span>.</span><span> </span><b><span>Conclusion:</span></b><span> We concluded that DMFT Index correlated to periodontal and oral hea</span><span>lth status and, it increased with the progression of the pat</span><span>ient’s age and</span><span> can be used in the epidemiological evaluation of periodontal and o</span><span>ral health status. 展开更多
关键词 Adult Age groups of Patients Dental Caries index Periodontal Status Salivary pH
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Superluminal light attenuated by strong dispersion of complex refractive index
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作者 Abdurahman Ahmed Yonis Vadim Nickolaevich Mal'nev Belayneh Mesfin Ali 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期477-481,共5页
The propagation of narrow packets of electromagnetic waves(EMWs) in frequency dispersive medium with the consideration of the complex refractive index is studied. It is shown that counting in the dispersion of the c... The propagation of narrow packets of electromagnetic waves(EMWs) in frequency dispersive medium with the consideration of the complex refractive index is studied. It is shown that counting in the dispersion of the complex refractive index within the context of the conventional expression of the group velocity of narrow wave packets of EMWs propagating in a dispersive medium results in the appearance of additional constraints on the group velocity, which dictates that the physically acceptable group velocity can only be realized in the case of a negligible imaginary part of the group index. In this paper, the conditions that allow one to realize the physically acceptable group velocity are formulated and analyzed numerically for the relevant model of the refractive index of a system of two-level atoms in the optical frequency range. It is shown that in the frequency band where superluminal light propagation is expected, there is a strong dispersion of the refractive index that is accompanied with strong absorption, resulting in a strongly attenuated superluminal light. 展开更多
关键词 group velocity group index superluminal light slow waves
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Finite Group with Two Supersolvable Subgroups of Coprime Indices 被引量:2
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作者 王坤仁 《Northeastern Mathematical Journal》 CSCD 2001年第2期221-225,共5页
In this paper, we obtain some classification theorems of finite simple groups with two subgroups of coprime indices which are both supersolvable or one supersolvable and the other nilpotent. Using these classification... In this paper, we obtain some classification theorems of finite simple groups with two subgroups of coprime indices which are both supersolvable or one supersolvable and the other nilpotent. Using these classification theorems, we prove some sufficient conditions of finite solvable groups. Finally, we provide a supplement of Doerks Theorem. 展开更多
关键词 solvable group supersolvable group simple group index
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STUDY OF A COMPREHENSIVE MONITORING INDEX FOR TWO TYPES OF ENSO EVENTS 被引量:1
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作者 曹璐 孙丞虎 +2 位作者 任福民 袁媛 江静 《Journal of Tropical Meteorology》 SCIE 2015年第2期153-160,共8页
Some recent studies presented two existing types of ENSO events, one is the Eastern-Pacific(EP) type and the other the Central-Pacific(CP) type. This study examined the monitoring ability of several current operationa... Some recent studies presented two existing types of ENSO events, one is the Eastern-Pacific(EP) type and the other the Central-Pacific(CP) type. This study examined the monitoring ability of several current operational ENSO indices. The results indicated that a single index could not distinguish the EP and CP in the historical ENSO events during 1950-2009. The Nio 3 index may only be suitable for monitoring the EP-type ENSO, while the Nio 4 index works only for the CP-type ENSO. In order to capture the occurrence of ENSO events and distinguish the type, we considered a new monitoring index group using Nio 3 and Nio 4 indices. Further analysis confirmed that this index group can monitor different types of historical ENSO events with different spatial distribution of sea surface temperature. It has a good performance in determining the characteristics of the ENSO events, including peak intensity, onset,decay, and mature phase. 展开更多
关键词 ENSO events Eastern-Pacific (EP) type Central-Pacific (CP) type ENSO index index group
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Frequency of Monthly Ejaculation at Sexual Intercourse, DNA Fragmentation Index and Fertilization Rate among Sperm Donors and Fertility-Challenged Men in Sub-Saharan Africa: Paper 1 被引量:1
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作者 Abayomi B. Ajayi Bamgboye M. Afolabi +6 位作者 Victor D. Ajayi Ifeoluwa O. Oyetunji Adedamilola Atiba Seun Saanu Ayodeji T. Adeoye Joy Ehichioya Ibukun I. Ayelehin 《Open Journal of Urology》 2019年第11期181-194,共14页
Introduction: In humans, the ideal ejaculation frequency depends on age, exercise and sexual potential. Natural ejaculation frequency balances the testosterone levels in the body. Materials and Methods: Semi-structure... Introduction: In humans, the ideal ejaculation frequency depends on age, exercise and sexual potential. Natural ejaculation frequency balances the testosterone levels in the body. Materials and Methods: Semi-structured questionnaire was used to collect information from subjects. Semen samples were collected from sperm donors and sub-fertile men who presented for infertility challenges. Processing and analysis of semen samples were done according to World Health Organization guidelines. Sperm DNA fragmentation was evaluated using the Halosperm&#174;?kit. Results: A total of 114 subjects, including 19 sperm donors and 95 sub-fertile males were studied. There was a significant difference (t =?&#8722;5.96, P-value = 0.00001) in the mean [±sd] age of sperm donors (30.8 [8.1]) and that of sub-fertile men (42.3 [76]). There was a significant difference (t=?&#8722;4.10, P-value = 0.0005) in the mean monthly ejaculation during sexual intercourse (MESI) among sperm donors with DNA fragmentation index &#8722;2.20, P-value = 0.02) in MESI among sub-fertile men aged ≥40 years (8.9 [4.6]) than among those aged &#8722;0.67, SE = 0.28, t = &#8722;2.40, P-value = 0.02, 95% CI: &#8722;1.24,?&#8722;0.10). Conclusion: In men < 40 years, fewer MESI did not worsen the DFI. A higher number of professionals such as doctors, lawyers and engineers, reported lower monthly frequency of sexual ejaculations compared to entrepreneurs. Entrepreneurs and non-smokers had the highest frequencies of MESI. 展开更多
关键词 MONTHLY Sexual EJACULATION Rate DNA Fragmentation index Male INFERTILITY Age group Body Mass index Social HABITS Black AFRICANS
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Precise Object Detection Using Iterative Superpixels Grouping Method
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作者 Cheng-Chang Lien Yu-Wei Lin +2 位作者 Huan-Po Hsu Kun-Ming Yu Ming-Yuan Lei 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第2期153-160,共8页
The region completeness of object detection is very crucial to video surveillance, such as the pedestrian and vehicle identifications. However, many conventional object detection approaches cannot guarantee the object... The region completeness of object detection is very crucial to video surveillance, such as the pedestrian and vehicle identifications. However, many conventional object detection approaches cannot guarantee the object region completeness because the object detection can be influenced by the illumination variations and clustering backgrounds. In order to overcome this problem, we propose the iterative superpixels grouping (ISPG) method to extract the precise object boundary and generate the object region with high completeness after the object detection. First, by extending the superpixel segmentation method, the proposed ISPG method can improve the inaccurate segmentation problem and guarantee the region completeness on the object regions. Second, the multi- resolution superpixel-based region completeness enhancement method is proposed to extract the object region with high precision and completeness. The simulation results show that the proposed method outperforms the conventional object detection methods in terms of object completeness evaluation. 展开更多
关键词 index Terms-lterative superpixels grouping method (ISPG) object completeness object detection superpixel video surveillance.
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Quantitative Structure-Property Relationship Research of Main Group Compounds 被引量:1
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作者 雷克林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第3期172-173,共2页
New appronches were applied to improve the molecular connectivity indices m^X^τ. The vertex valence is redefined and it was reasonable for hydrogen atom. The distances between vertices were used to propose novel conn... New appronches were applied to improve the molecular connectivity indices m^X^τ. The vertex valence is redefined and it was reasonable for hydrogen atom. The distances between vertices were used to propose novel connectivity topological indexes. The vertices and the distances in a molecular graph were taken into account in this definition. The linear regression was used to develop the structural property models. The results indicate that the novel connectivity topological indexes are useful model parameters for Quantitative Strncture-Property Relationship ( QSPR ) analysis. 展开更多
关键词 vertex connectivity topological index DISTANCE main group compounds QSPR
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Effects of Phenyl Content and Molecular Structure on the Refractive Index of Organic Silicon Polymer 被引量:1
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作者 朱淮军 戴子林 涂伟萍 《Journal of Donghua University(English Edition)》 EI CAS 2017年第4期503-506,共4页
The effects of phenyl content and group distribution on the refractive index of phenyl silicone oil were investigated by synthesis and characterization of silicone oils of different molecular structures.A group contri... The effects of phenyl content and group distribution on the refractive index of phenyl silicone oil were investigated by synthesis and characterization of silicone oils of different molecular structures.A group contribution function model was established to predict the refractive index. The results showed that refractive index of phenyl silicone oil increased as its phenyl content increased. A linear equation had been established to describe the quantitative relationship between the refractive index and phenyl content.Refractive index values from the group contribution function model showed good consistency with experimental results. 展开更多
关键词 phenyl silicone oil refractive index phenyl content group contribution method molecular structure
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面向老龄社会的社区建成环境可步行性测度研究 被引量:1
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作者 黄丽蒂 刘双双 +1 位作者 郑博丹 卫大可 《南方建筑》 CSCD 北大核心 2024年第1期107-114,共8页
选取大庆市设施布局、路网形态各异的老龄化社区为研究对象,对其可步行性展开研究。宏观与微观层面建立社区可步行性综合测度模型,利用AHP层次分析法对影响指标进行定性定量的测度评价;中观层面应用步行指数的方法对设施分布及可达性进... 选取大庆市设施布局、路网形态各异的老龄化社区为研究对象,对其可步行性展开研究。宏观与微观层面建立社区可步行性综合测度模型,利用AHP层次分析法对影响指标进行定性定量的测度评价;中观层面应用步行指数的方法对设施分布及可达性进行分析。结果表明:可步行性综合测度模型和步行指数可以较好的反映社区的可步行性;土地利用多样性、路网结构方式、设施分布及步行环境质量等因素都影响社区步行友好水平。建议:对于社区规划:构建合理路网结构,增加社区用地多样性,打造良好步行环境,提升老年人步行舒适性和愉悦性。对于建成社区:调整现有道路空间,优化停车空间和停车方式,健全社区养老服务设施体系。 展开更多
关键词 老龄化 可步行性 老年人 社区 步行指数
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Quantized Energy Momentum and Wave for an Electromagnetic Pulse—A Single Photon inside Negative Refractive Indexed Media
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作者 Shantanu Das 《Journal of Modern Physics》 2011年第12期1507-1522,共16页
An Electromagnetic (EM) radiation in dispersion less free space vacuum is represented by a photon, with corpuscular and wave nature. The discussions, for the past century aimed at the nature of photon inside a media h... An Electromagnetic (EM) radiation in dispersion less free space vacuum is represented by a photon, with corpuscular and wave nature. The discussions, for the past century aimed at the nature of photon inside a media having dispersion in the refraction property, other than free space. What about its nature if the space be of refractive index which is negative, is discussed in this paper. We call mechanical momentum, wave-momentum, and try to match our present theories with intriguing property of this ‘photon’ or pulse carrying EM energy packet, and more so we try to find its property energy, momentum inside a media a positive refractive media, and if the media show a negative refractive index behavior, then these queries are profound, and suitable explanations to these classical concepts of corpuscular-wave nature of photon inside these media are quest for the scientists dealing with these materials having negative index of refraction. Here some of this counterintuitive nature of corpuscular-wave nature of photon inside negative indexed material is brought out, with possible ‘new definition’ of its ‘wave-momentum’, the concept of ‘reactive energy’ inside negative indexed material, along with possible ‘new wave equation’. These definitions and expressions of ‘wave-momentum’ and ‘reactive energy’ pertaining to negative indexed material are new and discussed and derived by classical means. 展开更多
关键词 Negative Refractive indexed Material (NRM) group Refractive index Phase Refractive index WAVE MOMENTUM Mechanical MOMENTUM Reactive Energy
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从体部指数值探讨中国族群体部特征的共性
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作者 李咏兰 于会新 +3 位作者 宇克莉 张兴华 包金萍 郑连斌 《解剖学报》 CAS CSCD 2024年第5期619-624,共6页
目的探讨中国族群体部特征的共性。方法对中国62个族群的8项体部指数值进行分析。结果聚类分析发现,男性52个族群、女性59个族群聚入了北方族群为主的混合组及南方族群为主的混合组。8个汉族族群分别聚入各个组中,没有聚合出汉族组。体... 目的探讨中国族群体部特征的共性。方法对中国62个族群的8项体部指数值进行分析。结果聚类分析发现,男性52个族群、女性59个族群聚入了北方族群为主的混合组及南方族群为主的混合组。8个汉族族群分别聚入各个组中,没有聚合出汉族组。体部指数的分型结果表明,长躯干型、中胸型、宽肩型、宽骨盆型和中腿型是中国男性族群主要的体部类型。中躯干型、宽胸型、宽肩型、宽骨盆型和中腿型是中国女性族群主要的体部类型。这表现出中国各族群体部特征具有明显的一致性。中国族群体部特征的一致性与其族源相近有关,汉族在中国各个族群交流融合过程中起了重要作用。在汉族的历史上,出现过多次大规模的人口迁徙。北方少数民族南下融入北方汉族,北方汉族南下促进了南方汉族的形成,使得南方汉族与北方汉族体部特征具有相似性,也促进了南方少数民族融入南方汉族。此外,迁入少数民族地区的汉族也逐渐融入少数民族中。结论中国各族群体部特征存在明显的共性。 展开更多
关键词 体质特征 南方族群 北方族群 体部指数 活体测量
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Uncovering and Displaying the Coherent Groups of Rank Data by Exploratory Riffle Shuffling
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作者 Vartan Choulakian Jacques Allard 《Open Journal of Statistics》 2021年第1期178-212,共35页
Let <i><span>n</span></i><span> respondents rank order </span><i><span>d</span></i><span> items, and suppose that <img src="Edit_c36450fa-1b61-... Let <i><span>n</span></i><span> respondents rank order </span><i><span>d</span></i><span> items, and suppose that <img src="Edit_c36450fa-1b61-4116-be40-5bede8274d30.bmp" alt="" /></span><span><span>. Our main task is to uncover and display the structure of the observed rank data by an exploratory riffle shuffling procedure which sequentially decomposes the n voters into a finite number of coherent groups plus a noisy group: where the noisy group represents the outlier voters and each coherent group is composed of a finite number of coherent clusters. We consider exploratory riffle shuffling of a set of items to be equivalent to optimal two blocks seriation of the items with crossing of some scores between the two blocks. A riffle shuffled coherent cluster of voters within its coherent group is essentially characterized by the following facts: 1) Voters have identical first TCA factor score, where TCA designates taxicab correspondence analysis, an L</span><sub><span>1</span></sub><span> variant of corresponden</span><span>ce analysis;2) Any preference is easily interpreted as riffle shuffling of its items;3) The nature of different riffle shuffling of items can be seen in the structure of the contingency table of the first-order marginals constructed from the Borda scorings of the voters;4) The first TCA factor scores of the items of a coherent cluster are interpreted as Borda scale of the items. We also introduce a crossing index, which measures the extent of crossing of scores of voters between the two blocks seriation of the items. The novel approach is explained on the benchmarking SUSHI data set, where we show that this data set has a very si</span><span>mple structure, which can also be communicated in a tabular form.</span></span> 展开更多
关键词 Borda Score and Scale Exploratory Riffle Shuffle Coherent group Coherent Cluster Crossing index Taxicab Correspondence Analysis
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An Event Alarm System Based on Single and Group Human Behavior Analysis 被引量:1
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作者 Hung-Yu Yeh I-Cheng Chang Yung-Hsin Chen 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第2期123-132,共10页
Due to the increasing demand for security, the development of intelligent surveillance systems has attracted considerable attention in recent years. This study aims to develop a system that is able to identify whether... Due to the increasing demand for security, the development of intelligent surveillance systems has attracted considerable attention in recent years. This study aims to develop a system that is able to identify whether or not the people need help in a public place. Different from previous work, our work considers not only the behaviors of the target person but also the interaction between him and nearby people. In the paper, we propose an event alarm system which can detect the human behaviors and recognize the happening event through integrating the results generated from the single and group behavior analysis. Several new effective features are proposed in the study. Besides, a mechanism capable of extracting one-to-one and multiple-to-one relations is also developed. Experimental results show that the proposed approach can correctly detect human behaviors and provide the alarm messages when emergency events occur. 展开更多
关键词 index Terms Event alarm system group behavior analysis human behavior recognition single behavior analysis stooping curve.
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繁殖洄游期青海湖裸鲤雌雄个体及群体对栖息地底质偏好选择的差异
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作者 石小涛 卢建雨 +7 位作者 柯森繁 李冬晴 季怀耀 焦易林 王渊洋 祁洪芳 高生辉 涂志英 《水生生物学报》 CAS CSCD 北大核心 2024年第10期1780-1788,共9页
为明晰青海湖裸鲤(Gymnocypris przewalskii)对栖息地底质的偏好,研究通过青海湖裸鲤栖息地调查筛选出5种典型栖息地底质类型,在青海湖支流沙柳河刚北干渠搭建配置有5种底质类型的青海湖裸鲤生境模拟池,采用偏好指数量化法,确定了雌雄... 为明晰青海湖裸鲤(Gymnocypris przewalskii)对栖息地底质的偏好,研究通过青海湖裸鲤栖息地调查筛选出5种典型栖息地底质类型,在青海湖支流沙柳河刚北干渠搭建配置有5种底质类型的青海湖裸鲤生境模拟池,采用偏好指数量化法,确定了雌雄个体偏好底质类型及偏好强度,分析了影响青海湖裸鲤底质选择的内外因素。结果表明:(1)单尾青海湖裸鲤雌鱼个体沙砾底质访问时间最长(2540s),雄鱼个体中小卵石底质访问时间最长(1960s);(2)青海湖裸鲤雌鱼只偏好沙砾底质(PI=6595.8),雄鱼偏好3种底质类型,其中中小卵石偏好程度最高(PR=10.3);(3)青海湖裸鲤雄鱼在群体底质选择中会跟随雌鱼的选择偏好,沙砾底质访问时间最长(2051s)。研究旨在为青海湖裸鲤河道底质改造、“自然”栖息地的营造提供理论依据。 展开更多
关键词 性别 群体 栖息地 底质偏好 偏好指数 青海湖裸鲤
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基于双指标分组学习粒子群算法的动态敏捷软件项目调度
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作者 申晓宁 徐继勇 +2 位作者 毛鸣健 陈文言 宋丽妍 《计算机工程与科学》 CSCD 北大核心 2024年第10期1793-1806,共14页
针对敏捷软件开发中的用户故事选择和任务分配2个紧耦合子问题,考虑用户故事的新增和开发者工作时长的不确定性,构建敏捷软件项目的动态周期性调度模型,提出一种基于目标值和潜力值双指标进行分组学习的粒子群优化算法。该算法依据不同... 针对敏捷软件开发中的用户故事选择和任务分配2个紧耦合子问题,考虑用户故事的新增和开发者工作时长的不确定性,构建敏捷软件项目的动态周期性调度模型,提出一种基于目标值和潜力值双指标进行分组学习的粒子群优化算法。该算法依据不同分组特征选用相异的学习对象,以提高搜索的多样性;基于投资回报率和时间利用率设计初始化和局部搜索策略,以应对环境变化并增强挖掘能力。与7种已有算法相比,所提算法能够规划出一套产出价值更大和时间利用率更高的调度方案。 展开更多
关键词 敏捷开发 软件项目调度 双指标 分组学习 粒子群优化
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甘肃省某三甲医院医疗服务能力评价及改进措施探析
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作者 杜旦 张国华 +1 位作者 虢海月 张铭 《联勤军事医学》 CAS 2024年第6期528-532,共5页
目的基于疾病诊断相关分组(diagnosis-related groups,DRGs)应用过程的研究,评价甘肃省某三级甲等综合医院的医疗服务能力。方法收集作者医院2019-01-01/2021-12-31日住院病案首页数据,对DRGs指标数据进行对比分析,依据“二八原则”以... 目的基于疾病诊断相关分组(diagnosis-related groups,DRGs)应用过程的研究,评价甘肃省某三级甲等综合医院的医疗服务能力。方法收集作者医院2019-01-01/2021-12-31日住院病案首页数据,对DRGs指标数据进行对比分析,依据“二八原则”以相对权重(relativeweight,RW)和出院人次将全院734个DRGs组划分成优势病种区、核心病种区、重点病种区、普通病种区、提升病种区和下沉病种区,分析各科室病种分区情况。结果该医院总体病例组合指数(case-mixindex,CMI)呈略微下降趋势,出院人数增幅较大,2021年较2019年上升了10.73%,总手术占比、四级手术占比及微创手术占比分别上升了6.56%、3.62%、0.71%;时间消耗指数均<1且持续降低,药耗费用有所增加;有68.31%的出院患者均集中在RW<1的DRGs组;优势病种区和核心病种区各包括30和148个DRGs组,总体CMI分别为2.288和2.539,均处于较高水平;重点病种区和普通病种区各包括90和261个DRGs组,总体CMI相对较低,分别为0.837和0.800;提升病种区和下沉病种区各包括13和63个DRGs组,总体CMI分别为0.303和0.317,均处于较低水平。结论该院的医疗服务能力有所提升,但医疗服务效率有待改善。根据病种分区结果,进一步优化全院病种结构,增加优势病种、核心病种等高权重病种的患者收治比例。以目标值为导向,按月度开展DRGs病种分析和对比,逐步提升全院整体医疗服务能力,为患者提供更加优质的医疗服务。 展开更多
关键词 疾病诊断相关分组 病例组合指数 病种分区
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