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作者 燕雀 九遥(图) 《开心世界》 2009年第23期114-153,共40页
桃夭夭被水仙姐姐纠缠,恰好未婚妻龙百灵找上山来,水仙姐姐想和龙百灵比美斗艳,结果却落荒而逃。玄门首徒聚会自然宫,
关键词 《空门》 当代作品 文学 九遥
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Does antecolic reconstruction for duodenojejunostomy improve delayed gastric emptying after pylorus-preserving pancreaticoduodenectomy? A systematic review and meta-analysis 被引量:10
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作者 An-Ping Su Shuang-Shuang Cao Yi Zhang Zhao-Da Zhang Wei-Ming Hu Bo-Le Tian 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第43期6315-6323,共9页
AIM:To evaluate whether antecolic reconstruction for duodenojejunostomy (DJ) can decrease delayed gastric emptying (DGE) rate after pylorus-preserving pancreaticoduodenectomy (PPPD) through literature review and meta-... AIM:To evaluate whether antecolic reconstruction for duodenojejunostomy (DJ) can decrease delayed gastric emptying (DGE) rate after pylorus-preserving pancreaticoduodenectomy (PPPD) through literature review and meta-analysis. METHODS:Articles published between January 1991 and April 2012 comparing antecolic and retrocolic reconstruction for DJ after PPPD were retrieved from the databases of MEDLINE (PubMed), EMBASE, OVID and Cochrane Library Central. The primary outcome of interest was DGE. Either fixed effects model or random effects model was used to assess the pooled effect based on the heterogeneity. RESULTS:Five articles were identified for inclusion:two randomized controlled trials and three non-randomized controlled trials. The meta-analysis revealed that antecolic reconstruction for DJ after PPPD was associated with a statistically significant decrease in the incidence of DGE [odds ratio (OR), 0.06; 95% CI, 0.02-0.17; P < 0.00 001] and intra-operative blood loss [mean difference (MD), -317.68; 95% CI, -416.67 to -218.70; P < 0.00 001]. There was no significant difference between the groups of antecolic and retrocolic reconstruction in operative time (MD, 25.23; 95% CI, -14.37 to 64.83; P = 0.21), postoperative mortality, overall morbidity (OR, 0.54; 95% CI, 0.20-1.46; P = 0.22) and length of postoperative hospital stay (MD, -9.08; 95% CI, -21.28 to 3.11; P = 0.14). CONCLUSION:Antecolic reconstruction for DJ can decrease the DGE rate after PPPD. 展开更多
关键词 Pylorus-preserving pancreaticoduodenectomy Delayed gastric emptying Antecolic reconstruction Retrocolic reconstruction DUODENOJEJUNOSTOMY
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Spatio-temporal Variation of Landscape Heterogeneity under Influence of Human Activities in Xiamen City of China in Recent Decade 被引量:3
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作者 HUANG Yixiong YIN Xiuqin +5 位作者 YE Gongfu LIN Jiemin HUANG Ru WANG Na WANG Liang SUN Yue 《Chinese Geographical Science》 SCIE CSCD 2013年第2期227-236,共10页
Xiamen is an economically competitive and highly urbanized city along the coastal area of Fujian Province, China. The research on spatio-temporal variation of landscape heterogeneity under the influence of human activ... Xiamen is an economically competitive and highly urbanized city along the coastal area of Fujian Province, China. The research on spatio-temporal variation of landscape heterogeneity under the influence of human activities is of great importance to the further study on the relationship of landscape pattern and ecological process. It is also crucial to the discovery of spatial variation and intensity distribution of human activities. The research analyzed the intensity of human impacts and the spatial variation features and dynamics of landscape patterns by introducing statistical theories and approaches. We analyzed spatio-temporal variation of landscape heterogeneity using the geostatistical techniques, such as semivariogram and Kriging interpolation.Results show that there is a higher correlation between landscape heterogeneity indexes and human impact index. Both the indexes show a moderate spatial autocorrelation as well as an obvious characteristic of anisotropy. From 1998 to 2008, the spatial differentiation of the changes in the intensity of human activities and the changes in landscape heterogeneity shows that the landscape patterns in Xiamen are closely related with the urban land utilization methods, the condition of traffic and geographical location and the physical geographical condition such as the terrain and the ecological environment. The process of urbanization has a significant impact on the urban landscape pattern. 展开更多
关键词 landscape heterogeneity human impact index human activities Xiamen City
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Does delayed gastric emptying shorten the H pylori eradication period? A double blind clinical trial
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作者 Mohammad Hassan Emami Mohammad Mehdi Saberfiroozi +9 位作者 Abbas Arj Ali Reza Taghavi Kamran Bagheri-Lankarani Najaf Dehbashi Mohammad Reza Fattahi Mahvash Alizadeh Mohammad Javad Kaviani Rahim Bahri-Najafi Bita Geramizadeh Abbas Esmaeili 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第39期6310-6315,共6页
AIM: To evaluate the gastric emptying inhibitory effects of sugar and levodopa on H pylori eradication period. METHODS: A total of 139 consecutive patients were randomized into 6 groups. The participants with peptic u... AIM: To evaluate the gastric emptying inhibitory effects of sugar and levodopa on H pylori eradication period. METHODS: A total of 139 consecutive patients were randomized into 6 groups. The participants with peptic ulcer disease or non-ulcer dyspepsia non-responding to other medications who were also H pylori-positive patients either with positive rapid urease test (RUT) or positive histology were included. All groups were pretreated with omeprazole for 2 d and then treated with quadruple therapy regimen (omeprazole, bismuth, tetracycline and metronidazole); all drugs were given twice daily. Groups 1 and 2 were treated for 3 d, groups 3, 4 and 5 for 7 d, and group 6 for 14 d. Groups 1 to 4 received sugar in the form of 10% sucrose syrup. Levodopa was prescribed for groups 1 and 3. Patients in groups 2 and 4 were given placebo for levodopa and groups 5 and 6 received placebos for both sugar and levodopa. Upper endoscopy and biopsies were carried out before treatment and two months after treatment. Eradication of H pylori was assessed by RUT and histology 8 wk later.RESULTS: Thirty patients were excluded. Per-protocol analysis showed successful eradication in 53% in group 1, 56% in group 2, 58% in group 3, 33.3% in group 4, 28% in group 5, and 53% in group 6. Eradication rate, patient compliance and satisfaction were not significantly different between the groups. CONCLUSION: It seems that adding sugar or levodopa or both to anti H pylori eradication regimens may lead to shorter duration of treatment. 展开更多
关键词 HPYLORI Gastric emptying GLUCOSE LEVODOPA
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Approximate Toffoli Gate Originated from a Single Resonant Interaction of Cavity Dissipation and Atomic Spontaneous Emission
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作者 CHEN Chang-Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期871-876,共6页
We propose a potentially practical scheme to implement an approximate three-qubit Toffoli gate by a single resonant interaction in dissipative cavity QED in which the cavity mode decay and atomic spontaneous emission ... We propose a potentially practical scheme to implement an approximate three-qubit Toffoli gate by a single resonant interaction in dissipative cavity QED in which the cavity mode decay and atomic spontaneous emission are considered. The scheme does not require two-qubit controlled-NOT gates but uses a three-qubit phase gate and two Hadamard gates, where the approximate phase gate can be implemented by only a single dissipative resonant interaction of atoms with the cavity mode. Discussions are made for the advantages and the experimental feasibility of our scheme. 展开更多
关键词 Toffoli gate cavity QED dissipative resonant interaction
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Effects of Helicobacterpyloriinfection on gastric emptying rate in patients with non-ulcer dyspepsia 被引量:9
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作者 Grigoris I Leontiadis George I Minopoulos +4 位作者 Efstratios Maltezos Stamatia Kotsiou Konstantinos I Manolas Konstantinos Simopoulos Dimitrios Hatseras 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第12期1750-1754,共5页
AIM:The pathogenesis of delayed gastric emptying in patients with non-ulcer dyspepsia(NUD)remains unclear. We aimed to examine whether gastric emptying rate in NUD patients was associated with Helicobacter pylori(Hpyl... AIM:The pathogenesis of delayed gastric emptying in patients with non-ulcer dyspepsia(NUD)remains unclear. We aimed to examine whether gastric emptying rate in NUD patients was associated with Helicobacter pylori(Hpylori) infection and whether it was affected by eradication of the infection. METHODS:Gastric emptying rate of a mixed solid-liquid meal was assessed by the paracetamol absorption method in NUD patients and asymptomatic controls(n=17).Hpylori status was assessed by serology and biopsy urease test. H pylori-positive NUD patients(n=23)received 10-day triple eradication therapy.Hpyloristatus was re-assessed by biopsy urease test four weeks later,and if eradication was confirmed,gastric emptying rate was re-evaluated. RESULTS:Thirty-three NUD patients and 17 controls were evaluated.NUD patients had significantly delayed gastric emptying compared with controls.The mean maximum plasma paracetamol concentration divided by body mass (Cmax/BM)was 0.173 and 0.224 mg/L.kg respectively (P=0.02),the mean area under plasma paracetamol concentration-time curve divided by body mass(AUC/BM) was 18.42 and 24.39 mg.min/L.kg respectively(P=0.01). Gastric emptying rate did not differ significantly between H pylori-positive and H pylori-negative NUD patients.The mean Cmax/BM was 0.172 and 0.177 mg/L·kg respectively (P=0.58),the mean AUC/BM was 18.43 and 18.38 mg·min/ L·kg respectively(P=0.91).Among 14 NUD patients who were initially H pylori-positive,confirmed eradication of the infection did not significantly alter gastric emptying rate. The mean Cmax/BM was 0.171 and 0.160 mg/L.kg before and after Hp eradication,respectively(P=0.64),the mean AUC/BM was 17.41 and 18.02 mg.min/L.kg before and after eradication,respectively(P=0.93). CONCLUSION:Although gastric emptying is delayed in NUD patients compared with controls,gastric emptying rate is not associated with H pylori status nor it is affected by eradication of the infection. 展开更多
关键词 Gastric Emptying Helicobacter pylori ADULT Anti-Bacterial Agents DYSPEPSIA FEMALE Helicobacter Infections Humans MALE Middle Aged Treatment Outcome
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Spatial-Temporal Pattern and Driving Forces of Land Use Changes in Xiamen 被引量:41
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作者 QUAN Bin CHEN Jian-Fei +4 位作者 QIU Hong-Lie M. J. M. ROMKENS YANG Xiao-Qi JIANG Shi-Feng LI Bi-Cheng 《Pedosphere》 SCIE CAS CSCD 2006年第4期477-488,共12页
Using Landsat TM data of 1988, 1998 and 2001, the dynamic process of the spatial-temporal characteristics of land use changes during 13 years from 1988 to 2001 in the special economic zone of Xiamen, China was analyze... Using Landsat TM data of 1988, 1998 and 2001, the dynamic process of the spatial-temporal characteristics of land use changes during 13 years from 1988 to 2001 in the special economic zone of Xiamen, China was analyzed to improve understanding and to find the driving forces of land use change so that sustainable land utilization could be practiced. During the 13 years cropland decreased remarkably by nearly 11304.95 ha. The areas of rural-urban construction and water body increased by 10 152.24 ha and 848.94 ha, respectively. From 1988 to 2001, 52.5% of the lost cropland was converted into rural-urban industrial land. Rapid urbanization contributed to a great change in the rate of cropland land use during these years. Land-reclamation also contributed to a decrease in water body area as well as marine ecological and environmental destruction. In the study area 1) urbanization and industrialization, 2) infrastructure and agricultural intensification, 3) increased affluence of the farming community, and 4) policy factors have driven the land use changes. Possible sustainable land use measures included construction of a land management system, land planning, development of potential land resources, new technology applications, and marine ecological and environmental protection. 展开更多
关键词 driving force GIS land use change remote sensing XIAMEN
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Seismic Design Loads of Truss Arch Frames with Ceilings subjected to Vertical and Horizontal Earthquake Motions
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作者 Koichiro Ishikawa 《Journal of Mathematics and System Science》 2017年第11期308-315,共8页
Spatial structures such as a gymnasium and an exhibition hall often use ceilings because of enhancing sound effects and reducing heating bills. Although the ceiling members fell down on a large scale due to the seismi... Spatial structures such as a gymnasium and an exhibition hall often use ceilings because of enhancing sound effects and reducing heating bills. Although the ceiling members fell down on a large scale due to the seismic motion according to the past great earthquake disaster reports, structural engineers particularly do not carry out the seismic design. The study gives structural engineers the equivalent static loads for the design of the earthquake-proof design of the ceiling system. In particular, it is significant to investigate the dynamic behavior and the applied seismic loads for the complicated vibration of the long span arch building structures with RC columns. 展开更多
关键词 Truss arch frame RC column Knee brace Vertical and horizontal earthquake motions Earthquake-proof design Equivalent static load Dominant natural mode
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Jnconventional Geometric Phase Gate with Superconducting Quantum Interference Device Qubits in Cavity QED
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作者 YANG Wen-Xing CHEN Ai-Xi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期913-918,共6页
In the system with superconducting quantum interference devices (SQUID) in cavity, a scheme for constructing two-qubit quantum phase gate via a conventional geometric phase-shift is proposed by using a quantized cav... In the system with superconducting quantum interference devices (SQUID) in cavity, a scheme for constructing two-qubit quantum phase gate via a conventional geometric phase-shift is proposed by using a quantized cavity field and classical microwave pulses. In this scheme, the gate operation is realized in the subspace spanned by the two lower flux states of the SQUID system mud the population operator of the excited state has no effect on it. Thus the effect of decoherence caused from the levels of the SQUID system is possible to minimize. Under cavity decay, our strictly numerical simulation shows that it is also possible to realize the unconventional geometric phase gate. The experimental feasibility is discussed in detail. 展开更多
关键词 superconducting quantum interference devices cavity QED geometric quantum gates
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Analysis of Doors and Windows on the Function and Design of Building
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作者 Yu LAN 《International Journal of Technology Management》 2015年第3期68-70,共3页
The doors and windows are the throat of the building. This paper discusses the fundamental role of the doors and windows of the building, and the dominant roles such as spatial organization and control of light, and t... The doors and windows are the throat of the building. This paper discusses the fundamental role of the doors and windows of the building, and the dominant roles such as spatial organization and control of light, and to study the recessive function of windows and doors from aspects of the psychological impact, cultural significance and decoration. After exploring the characteristics of modem windows and doors, it studies the design elements of modem windows and doors and summed up the features that the initiative to make use of the environment. Basic from three levels as the basic form of design; windows and buildings, and the social and natural environment of the unified design; doors and windows to take the initiative to study the nature. 展开更多
关键词 windows and doors SPACE construction DESIGN
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Engagement and Commitment Among Teachers Working in Subsidized Secondary Education in Catalonia
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《Sociology Study》 2013年第10期763-772,共10页
This paper discusses the notion of commitment--a construct used in the psychology of work--and engagement, as hypothetically opposed to the concept of burnout used in the paradigm of positive psychology. The aim of th... This paper discusses the notion of commitment--a construct used in the psychology of work--and engagement, as hypothetically opposed to the concept of burnout used in the paradigm of positive psychology. The aim of this study is to analyze engagement in a group of 132 high school teachers from various schools in the private sector and identify its relationship with the commitment variable. The results of the work of this group in three dimensions are presented in this study: vigor, dedication, and absorption; the correlation data are also presented with organizational commitment in three dimensions: affective, normative and temporal (or continuity). With these results the aim is to find predictive evidence among teachers who score significantly in the three dimensions of engagement and the three dimensions of commitment. 展开更多
关键词 ENGAGEMENT COMMITMENT EDUCATION TEACHERS ORGANIZATION
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Bilateral shear strength of rectangular frame column based on simplified space truss-arch model
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作者 董春敏 《Journal of Chongqing University》 CAS 2010年第4期195-200,共6页
To investigate the bilateral shear strength of rectangular frame column subjected to oblique horizontal load, we presented a simplified space truss-arch model developed from unilateral truss-arch model. Main parameter... To investigate the bilateral shear strength of rectangular frame column subjected to oblique horizontal load, we presented a simplified space truss-arch model developed from unilateral truss-arch model. Main parameters in the new model were the cross-sectional area, transverse reinforcement raito, axial load, and material strength of the column. The reduction coefficient of concrete sterength owing to the severe cracking of column was also introduced in the model. Finally, 14 specimens under oblique horizontal load were tested to verified the feasibility and applicability of the space truss-arch model. 展开更多
关键词 space truss-arch model rectangular frame column bilateral shear strength oblique horizontal load experimental research
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Association of CagA and VacA presence with ulcer and non-ulcer dyspepsia in a Turkish population 被引量:8
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作者 Kantarceken Bulent Aladag Murat +7 位作者 Atik Esin Koksal Fatih Harputluoglu MMMurat Harputluoglu Hakan Karincaoglu Melih Ares Mehmet Yildirim Bulent Hilmioglu Fatih 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第7期1580-1583,共4页
AIM:The mostly known genotypic virulence features,of H.pylori are cytotoxin associated gene A (cagA) and Vacuolating cytotoxin gene A (VacA).We investigated the association of these major virulence factors with ulcer ... AIM:The mostly known genotypic virulence features,of H.pylori are cytotoxin associated gene A (cagA) and Vacuolating cytotoxin gene A (VacA).We investigated the association of these major virulence factors with ulcer and non-ulcer dyspepsia in our region. METHODS:One hundred and forty two dyspeptic patients were studied (average age 44.8±15.9 years,range 15-87 years,64 males and 78 females).Antral and corpus biopsies were taken for detecting and genotyping of H.pylori.107 patients who were H.pylori positive by histological assessment were divided into three groups according to endoscopic findings:Duodenal ulcer (DU),gastric ulcer (GU) and non-ulcer dyspepsia (NUD).The polymerase chain reaction (PCR) was used to detect CagA and VacA genes of H.pylori using specific primers. RESULTS:H.pyloriwas isolated from 75.4% (107/142) of the patients.Of the 107 patients,66 (61.7%) were cagA- positive and 82 (76.6%) were VacA-positive.CagA gene was positively associated with DU and GU (P<0.01,P<0.02), but not with NUD (P>0.05).Although VacA positivity in ulcer patients was higher than that in NUD group,the difference was not statistically significant (P>0.05). CONCLUSION:There is a significantly positive association between CagA genes and DU and GU.The presence of VacA is not a predictive marker for DU,GU,and NUD in our patients. 展开更多
关键词 Adolescent Adult Aged Aged 80 and over Antigens Bacterial Bacterial Proteins Biopsy DYSPEPSIA Female Genotype Helicobacter Infections Helicobacter pylori Humans Male Middle Aged Predictive Value of Tests Prevalence Stomach Ulcer Turkey VIRULENCE
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Assessment of natural radioactivity levels in Yemen rocks
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作者 Haman Mohamed Diab Abou Bakr A. Ramadan Abdel-Hamed Osman 《Journal of Environmental Science and Engineering》 2009年第7期58-63,共6页
Studies on radiation level and radionuclide distribution in Yemen were studied. The samples were collected from eight locations: Ma'rib, A1 Jawf, Sana'a, Dhamar, Amran, Ibb, Al Bayda and Al Dalea. The purpose of th... Studies on radiation level and radionuclide distribution in Yemen were studied. The samples were collected from eight locations: Ma'rib, A1 Jawf, Sana'a, Dhamar, Amran, Ibb, Al Bayda and Al Dalea. The purpose of this study is to provide a baseline map of radioactivity background levels in the investigated area and this study will be used as reference information to assess any change in the radioactive background level due to geological processes. The highest values of 22~ and 2~l'h concentrations (8797.2 and 24984.1 Bq.kg"l, respectively) were observed at A1 Jawf, region, whereas the highest average value of 40K concentration was 1561.9 Bq.kg-1. The investigation of the geological maps of the area under study showed that the surface rock outcrops consist mainly of granites, diorite, granodiorite, gneisses, and schists. All these rock types arc known to be rich in radioactive materials, which are considered natural sources for gamma radiation. The low mdiological background characterizing some Yemeni rocks could be attributed to nature of these rocks which consist of lime stone (sands and gravels). The absorbed dose rate in air was found to be in the range between 5.40 and 45.11 nGy.h-1 depending on the geological features, and radium equivalent activity concentration was found in the range between 29.57 and 71.85 Bq.kg-1. Also the representative extcmal hazard index values for the corresponding samples were also estinlated and given. 展开更多
关键词 natural radioactivity gamma radiation soil ROCK elemental concentration POTASSIUM THORIUM URANIUM
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Beyond Public Spaces: Shared Spaces in the Contemporary City
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作者 Giulia Setti 《Journal of Civil Engineering and Architecture》 2013年第7期833-840,共8页
The text aims to investigate the relevance of the concept of"public space" and the continuous variations which have changed its meaning. Going beyond the concept of public space, the author can understand the semant... The text aims to investigate the relevance of the concept of"public space" and the continuous variations which have changed its meaning. Going beyond the concept of public space, the author can understand the semantic boundaries of this definition: Today, relational spaces and shared spaces are the forms with which people can express the concept of public space. The gradual spread of new forms of communication has transformed the static view of public space in a more dynamic condition, the distinction between square, street, garden has lost its meaning leaving space to fragments and residues. Contemporary public spaces are defined, as the residual places that come from the abandonment of industries. The large mono-functional voids, which originate from industrial dismantlement, should be strategically reconsidered as new shared public spaces, where the integration between different functions leads to reactivate new forms of re-using of built space. 展开更多
关键词 Time-space relational spaces shared public spaces HYBRIDIZATION degrees of publicity.
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Spatial Landuse and Farming System Analyses of Reclaimed Tidal Lowland in South Sumatra, Indonesia
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作者 Adzemi Mat Arshadl Mustika Edi Armanto +1 位作者 Elisa Wildayana Ahmad Syahrial 《Journal of Environmental Science and Engineering(B)》 2012年第3期354-362,共9页
This study aims to analyze spatial landuse and farming system of reclamated tidal lowland in South Sumatra, Indonesia by using remote sensing technology and GIS in knowing the distribution of landuse change of tidal l... This study aims to analyze spatial landuse and farming system of reclamated tidal lowland in South Sumatra, Indonesia by using remote sensing technology and GIS in knowing the distribution of landuse change of tidal lowland. From these conditions, it can see cropping patterns on each of the secondary block and its relation to the condition of the water system network. The study was carried out in Delta Saleh areas. The used methodology was field survey and remote sensing technique. It was combined with GIS technology for spatial analysis. Over the last 11 years (1992-2002), a decline in the paddy field area is from 23,619.4 ha to 18,518.40 ha (27.65%). A decrease of river acreage (water body) occurred from 6,643.53 ha to 6,559.83 ha. In 1992 it has not detected any coconut plantation, while in 2001 it showed an area of coconut plantation 3,422.84 ha and 3,822.84 ha in 20l l. Significant changes are also presented in primary mangrove forest, widespread declining around 1,940.88 ha (147.20%). Most of the mangrove forest was converted into secondary mangrove forest and scrub. Linkage with topography type showed that the land with topography Type A was majority for paddy fields 250.28-262.80 ha (62.72%-65.59%). Mixed crop fields were in second place with acreage of 90.66-107.36 ha (22.72%-26.80%). The land with topography Type B showed the widest paddy fields (283.14-314.20 ha or 70.70%-78.48%), followed by upland crops. The land with topography Type C showed that paddy fields were 283.03-300.41 ha (70.66%-75.02 %), followed by upland crops 94.85-102.78 ha (23.69%-25.66%), and coconut was the smallest 0.09-0.27 ha. Generally, the cropping index was 100 on PS-I (planting season 1) for BL-I (business land 1) and BL-2 planted with paddy fields, while the PS-2 are generally not cultivated land (fallow). 展开更多
关键词 LANDUSE farming system ANALYSES reclamated tidal lowland South Sumatra Indonesia.
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Realization of Quantum Circuits in Fock Space
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作者 MALei LIYun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第5期787-789,共3页
In this letter, by using the method we offered in our paper [L. Ma and Y.D. Zhang, Commun. Theor. Phys.(Beijing, China) 36 (2001) 119], some extended quantum logic gates, such as quantum counter, quantum adder, are st... In this letter, by using the method we offered in our paper [L. Ma and Y.D. Zhang, Commun. Theor. Phys.(Beijing, China) 36 (2001) 119], some extended quantum logic gates, such as quantum counter, quantum adder, are studied and their expressions are given. It may be useful for us to study the more complicated quantum logic circuits deeply. 展开更多
关键词 quantum computer quantum logic gate quantum circuit
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Analysis of Dynamic Variations of Crustal Density in the Longmenshan Area before the Wenchuan M_S8.0 Earthquake
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作者 Li Yuan Niu Anfu +1 位作者 Liu Xikang Zhao Jing 《Earthquake Research in China》 CSCD 2015年第3期303-318,共16页
Based on the repeated gravity observation data from 1996 to 2007 from the Longmenshan gravity network, which has been dealt with by adjustment processing, the benchmark interference removal and impact of elevation cha... Based on the repeated gravity observation data from 1996 to 2007 from the Longmenshan gravity network, which has been dealt with by adjustment processing, the benchmark interference removal and impact of elevation changes removal, and by using the 3-D inversion method to reflect underground density, we analyze the characteristics of Longmenshan regional dynamic crustal density at depths of 25km, 20km and 15kin. The results show that in the Wenchuan earthquake preparation process, the regional density field showed marked characteristics both in time and space distribution. From the point of time process, the density change trend in the ten years before the earthquake presents a periodic change pattern: steady phase, dramatic stage, slow reducing phase and slow increase phase. The degree of density changes is from large to small, which means that earthquake gestation has reached the final stage. From the point of space distribution, density change distribution has a tendency of "dispersion--relative concentration", this shows that before the earthquake, the entropy of the underground density field was decreased. In addition, dramatic density changes often occur in the Longmenshan fault zone and western Sichuan plateau. Also, with the increase of depth, the trend of density change is more and more obvious. Through comparative analysis, the influence of density change on gravity is much bigger than that from height change. 展开更多
关键词 3-D inversion Dynamic change of density Wenchuan earthquakeLongmenshan fault zone The influence factors of gravity
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Transmit Antenna Selection in MIMO-OFDM System Based on CO-SFBC Schemes
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作者 仇润鹤 金彦龄 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期738-746,共9页
A transmit antenna selection(TAS)multi-input multi-output orthogonal frequency-division multiplexing(MIMO-OFDM)system based on channel-orthogonalized space-frequency block coding(CO-SFBC)schemes was proposed for bette... A transmit antenna selection(TAS)multi-input multi-output orthogonal frequency-division multiplexing(MIMO-OFDM)system based on channel-orthogonalized space-frequency block coding(CO-SFBC)schemes was proposed for better performance.Firstly,the principles and criterions for designing CO-STBC/SFBC schemes with angle feedback were proposed,and then the effect of quantization for the feedback angle information within such schemes was discussed.Meanwhile,the TAS scheme was applied to the system to further improve the overall performance.Simulation results show that the combination of the proposed CO-STBC and TAS schemes can significantly improve the system performance,which is much larger than only applying them to systems individually. 展开更多
关键词 multiple-input multiple-output(MIMO) orthogonal frequency-division multiplexing(OFDM) channel-orthogonalized space-frequency block coding(CO-STBC/SFBC) transmit antenna selection(TAS)
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Roof design of China Southern Airlines No.1 Hangar in Beijing Daxing International Airport
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作者 ZHAO Bo-you SHEN Jin-long WEI Heng 《空间结构》 CSCD 北大核心 2024年第3期88-96,共9页
To overcome the limitations of structural height imposed by airspace restrictions in the design of maintenance hangar roofs with long spans,a new diagonal truss roof structural system is introduced for the first time.... To overcome the limitations of structural height imposed by airspace restrictions in the design of maintenance hangar roofs with long spans,a new diagonal truss roof structural system is introduced for the first time.In the design of China Southern Airlines No.1 Hangar,4 main trusses were arranged diagonally along the depth direction,forming a W-shape truss.3 lineshaped trusses were arranged along the span direction,and double-layer space latticed structure is laid on them.The design optimized the height of the 183 m+222 m super long-span roof to 11.5 m,the maximum dimension the site could provide,so that the building height is within the permitted 40m.The steel consumption of the roof is only 165 kg/m^(2).The installation of diagonal trusses changed the unidirectional load transmission path of the roof and enhanced the spatial load transmission,effectively relieving the burden on the gate-side truss.This design enables the implementation of a maintenance hangar with a 222 m-span and heavy roof within the constraints of low airspace height. 展开更多
关键词 HANGAR diagonal truss line-shaped truss gate-side truss airspace height limit site
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