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“角里”音读考
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作者 陈建生 《安徽广播电视大学学报》 1999年第1期89-92,共4页
“角里”的写法与音读是学术界长期聚讼不已的问题之一。│k│组声母(舌根音)和l声母(边音)为什么能互相转换?牵涉到音韵学的一桩公案———即上古汉语究竟有无复辅音。本文认为转换的原因在于音节的失落与增生。其不同于一般的... “角里”的写法与音读是学术界长期聚讼不已的问题之一。│k│组声母(舌根音)和l声母(边音)为什么能互相转换?牵涉到音韵学的一桩公案———即上古汉语究竟有无复辅音。本文认为转换的原因在于音节的失落与增生。其不同于一般的异读,而且与前人所谓的缓读、急读也不尽相同。汉字“六书”中的“转注”,也与音节的失落与增生有关。此种现象的产生早于“反切”的出现。产生音节失落与增生的原因,除了书面语和口语的差异,还有雅言与俗语的不同。黄侃先生的“叠韵互音” 展开更多
关键词 “角里” 音读
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Shape retrieval using multi-level included angle functions-based Fourier descriptor 被引量:1
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作者 徐国清 穆志纯 徐烨 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期22-26,共5页
An effective shape signature namely multi-level included angle functions MIAFs is proposed to describe the hierarchy information ranging from global information to local variations of shape.Invariance to rotation tran... An effective shape signature namely multi-level included angle functions MIAFs is proposed to describe the hierarchy information ranging from global information to local variations of shape.Invariance to rotation translation and scaling are the intrinsic properties of the MIAFs.For each contour point the multi-level included angles are obtained based on the paired line segments derived from unequal-arc-length partitions of contour.And a Fourier descriptor derived from multi-level included angle functions MIAFD is presented for efficient shape retrieval.The proposed descriptor is evaluated with the standard performance evaluation method on three shape image databases the MPEG-7 database the Kimia-99 database and the Swedish leaf database. The experimental results of shape retrieval indicate that the MIAFD outperforms the existing Fourier descriptors and has low computational complexity.And the comparison of the MIAFD with other shape description methods also shows that the proposed descriptor has the highest precision at the same recall value which verifies its effectiveness. 展开更多
关键词 shape description image retrieval MULTI-LEVEL included angle function Fourier descriptor
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Braid-Delta Deposits from a Broad Shallow-Marine Setting: the Middle Member of the Kalpingtag Formation in the Central Tarim Basin 被引量:1
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作者 JIANG Yiming ZHANG Jinliang 《Journal of Ocean University of China》 SCIE CAS 2008年第2期145-153,共9页
During the early Silurian, a transgressive and vast shallow sea with flat sea-floor covered the central Tarim Basin (the Tazhong area). The depositional environment of the middle member of the Kalpingtag Formation is ... During the early Silurian, a transgressive and vast shallow sea with flat sea-floor covered the central Tarim Basin (the Tazhong area). The depositional environment of the middle member of the Kalpingtag Formation is controversial. In order to provide a basis for the prediction of reservoir sand, the sedimentary facies are recognized according to abundant core observations and de- scriptions combined with well-log analysis, isograms, seismic interpretations and regional sedimentary background. The middle member of the Kalpingtag Formation, which shows a retrograding sequence, is interpreted as braid-delta deposits influenced by mi- nor tidal reworking. The sources of clasts are from the southern uplift. The subaqueous braid-delta deposits in the study area have some characteristics quite different from the common deltas that generally deposit in marginal seas. Four facies grouped to a delta front association are recognized, ranging from distributary-channel (Facies A), front bar (Facies B), sand sheet (Facies C) and inter- distributary bay (Facies D). The distributary channels construct the sandbody framework of the delta front. Front bar deposits, which are fine-grained with low depositional dips, display a near-continuous sand strip around the entire periphery of the delta. Sand sheet deposits are mainly found in front of Facies B, gradationally contacting with the prodelta. The interdistributary bay is essentially the uppermost unit capping the channel sequence and generally made up of laminated and massive mudstones. The delta front deposits display extensive sheet-like bodies contrasting with the characteristic wedge shapes of common subaqueous delta bodies. The bi- modal cross-stratification and mud drapes in the fine- to medium-grained sandstone in the distal area are inferred to reflect high-energy tidal processes. 展开更多
关键词 Tazhong area SILURIAN Kalpingtag Formation shallow sea braid delta
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The Long-Term Morphodynamic of Barito Delta, Southern Kalimantan, Indonesia
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作者 Deasy Arisanty Junun Sartohadi Muh. Aris Marfai Danang Sri Hadmoko 《Journal of Environmental Science and Engineering(B)》 2012年第10期1196-1202,共7页
Barito Delta morphodynamic had contradictive role with its potency and problem. Potency in Barito Delta may support the development of Banjarmasin City, but development of Barito Delta may decrease the capacity of tra... Barito Delta morphodynamic had contradictive role with its potency and problem. Potency in Barito Delta may support the development of Banjarmasin City, but development of Barito Delta may decrease the capacity of transportation in Barito River. Multitemporal topographic map and Landsat satellite image during the period 1862-2008 were used to analyze the long-term delta morphodynamic. The analysis consisted of delta growth, yearly growth, growth orientation, delta shape, and shoreline changes. The research showed that the Barito Delta had developed during the period 1862-2008. Barito Delta had developed to south orientation. The growth of Barito Delta during the period 1862-1946 was 27.82 km^2 or 0.33 km^2/year. However, during the period 1946-1997, Barito Delta growth was 175.82 km^2 or 3.45 km^2/year. Area of Barito Delta decreased during the period 1997-2004. The reduction of Barito Delta area was 4.73 km^2 or 0.67 km^2/year. Area of Barito Delta in years 2004-2008 increased about 3.38 km^2 or 0.84 km^2/year Shoreline during the period 1862-2008 had changed. Accretion occurred in Kuala Lupak River during the period 1862-1997, but erosion occurred during the period 1997-2004. The delta morphodynamics were influenced by human activities in watershed and delta such as landuse change and land degradation. 展开更多
关键词 Morphodynamic Barito Delta topography map Landsat satellite image.
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Recognition of the Head of Submarine Canyon at the Base of Mahaweli River Delta, Sri Lanka
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作者 Upali de Silva Jayawardena 《Journal of Shipping and Ocean Engineering》 2014年第9期271-278,共8页
The coastal region around Sri Lanka have been subjected to considerable changes since Pleistocene and one remarkable observation is the occurrence of submarine canyons in eight places of the Island. The literature say... The coastal region around Sri Lanka have been subjected to considerable changes since Pleistocene and one remarkable observation is the occurrence of submarine canyons in eight places of the Island. The literature says that the head of the largest canyon at Trincomalee is situated 200 m from the shore. The objective of this paper is to highlight the extension of the canyon structure by studying the recent geotechnical investigations around the Mahaweli delta. A number of boreholes were constructed for groundwater investigations around the Mahaweli river floodplains and the other boreholes were constructed to determine the depth to the bedrock for a bridge foundation at the river outfall. The depth to the bedrock at the river outfall is more than 75 m and decreases towards upstream. The shape of the bedrock below the thick fluvial sediments in the studied area indicates the head of canyon should be marked more than 35 km from the shore towards inland. It is obvious that the submarine canyon at Trincomalee is only a part of a very large canyon. The thick fluvial sedimentary deposit over this canyon within the land is a result of erosion of bedrock along a shear zone or fault and then the rise of sea level in recent times. 展开更多
关键词 CANYON bedrock surface ALLUVIUM shear zone river erosion.
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An Addressing and Routing Scheme Based on Modified Euclidean Space for Hexagonal Networks
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作者 GONG Jiezhong LI Lin +2 位作者 CHEN Gongliang WU Yue LI Jianhua 《China Communications》 SCIE CSCD 2015年第5期94-99,共6页
The addressing and routing algorithm on hexagonal networks is still an open problem so far.Although many related works have been done to resolve this problem to some extent,the properties of hexagonal networks are sti... The addressing and routing algorithm on hexagonal networks is still an open problem so far.Although many related works have been done to resolve this problem to some extent,the properties of hexagonal networks are still not explored adequately.In this paper,we first create an oblique coordinate system and redefine the Euclidean space to address the hexagonal nodes.Then an optimal routing algorithm using vectors and angles of the redefined Euclidean space is developed.Compared with the traditional 3-directions scheme and the Cayley graph method,the proposed routing algorithm is more efficient and totally independent of the scale of networks with two-tuples addresses.We also prove that the path(s) obtained by this algorithm is always the shortest one(s). 展开更多
关键词 hexagonal network euclidean space ADDRESSING routing algorithm cayley graph
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The Raid of the "Plus Ultra". The First Aerial Crossing of the South Atlantic Ocean
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作者 Jose Sanchez Mendez 《History Research》 2015年第4期197-207,共11页
When World War I ended in 1918 the aviators wanting to fly higher and further and they started a raced in which everyone wanted to be first. The Spanish pilots were initially excluded by the Moroccan War, which demand... When World War I ended in 1918 the aviators wanting to fly higher and further and they started a raced in which everyone wanted to be first. The Spanish pilots were initially excluded by the Moroccan War, which demanded all available air forces be used to put an end to the conflict. Motivated by the successes of The Alhucemas amphibious landing, one of best Spanish aviators, Major Ramon Franco presented to the Government in 1925 a project to undertake a flight to Argentina across the South Atlantic Ocean in a DornierJ Wal seaplane. In the memorandum, Franco said: The Spain-Argentina flight would be a worthwhile trial and verification of air navigation. It would also serve to let the entire world know of the merits of our Aviation and allow us to occupy the aeronautical place that belongs to us in aeronautics. It would also help us strengthen our ties with our brothers at the other side of the ocean. The DornierJ Walwas named "Plus Ultra" referring to the Discovery of America. The route should be Palos de la Frontera-Las Palmas de Gran Canaria-Cape Verde islands-Fernando Noronha island-Pernambuco-Rio de Janeiro-Montevideo and Buenos Aires. Franco reasoned that the best time of year to make the flight was from December to April. The raid started in the city Palos de la Frontera on 22 January 1926 and ended in Buenos Aires on February 9, after flying 10,825 kilometers in 59 hours and 48 minutes. 展开更多
关键词 Ramon Franco DornierJ Wal "Plus Ultra" Palos de la Frontera Buenos Aires
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WAXD and FTIR Studies of Electron Beam Irradiated Biodegradable Polymers
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作者 Yasko Kodama Nelson Batista de Lima +5 位作者 Clfiudia Giovedi Luci Diva Brocardo Machado Wilson Aparecido Parejo Calvol Akihiro Oishi Kazuo Nakayama 《Journal of Physical Science and Application》 2012年第4期80-87,共8页
Poly(L-lactic acid) (PLLA) and poly(e-caprolactone) (PCL) have been receiving much attention lately due to their biodegradability in human body as well as in the soil, also due to their biocompatibility, envir... Poly(L-lactic acid) (PLLA) and poly(e-caprolactone) (PCL) have been receiving much attention lately due to their biodegradability in human body as well as in the soil, also due to their biocompatibility, environmentally friendly characteristics and non-toxicity. Morphology of biodegradable polymers affects the rate of their biodegradation. A polymer that has high degree of crystallinity will degrade at a slower rate due to the inherent increased stability. PCL homopolymer crosslinking degree increases with increasing doses of high energy radiation. On the other hand, the irradiation ofPLLA homopolymer promotes mainly chain-scissions at doses below 250 kGy. In the present work, twin screw extruded films of PLLA and PCL biodegradable homopolymers and 50:50 (w:w) blend were electron beam irradiated using electron beam accelerator Dynamitron (E = 1.5 MeV) from Radiation Dynamics, Inc. at doses in the range of 50 kGy to 103 kGy in order to evaluate the effect of electron beam radiation. Wide-angle X-ray diffraction (WAXD) patterns of non irradiated and irradiated samples were obtained using a diffractometer Rigaku Denki Co. Ltd., Multiflex model; and Fourier transform infrared spectroscopy (FTIR) spectra was obtained using a NICOLET 4700, attenuated total reflectance (ATR) technique. By WAXD patterns of as extruded non irradiated and irradiated PLLA it was verified broad diffusion peaks corresponding to amorphous polymer. There was a slight increase of the mean crystallite size of PCL homopolymer with increasing radiation dose. PCL crystalline index (CI) decreased with radiation dose above 500 kGy. But then, PLLA CI increased with radiation dose above 750 kGy. From another point of view, PLLA presence on the 50:50 blend did not interfere on the observed mean crystallite size increase up to 250 kGy. From 500 kGy to 103 kGy the crystallite size of PCL was a little bigger in the blend than the homopolymer. In contrast, FTIR results have shown that this technique was not sensitive enough to observe the degradation promoted by ionizing radiation of the studied homopolymers and blends, and neither on the miscibility of the blends. 展开更多
关键词 Biodegradable polymers PLLA PCL electron beam WAXD FTIR.
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ACCURACY ANALYSIS FOR QUASI-CAREY ELEMENT 被引量:17
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作者 Dongyang SHI Xiaobin HAO 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2008年第3期456-462,共7页
In this paper, a new triangular element (Quasi-Carey element) is constructed by the idea of Specht element. It is shown that this Quasi-Carey element possesses a very special property, i.e., the consistency error is... In this paper, a new triangular element (Quasi-Carey element) is constructed by the idea of Specht element. It is shown that this Quasi-Carey element possesses a very special property, i.e., the consistency error is of order O(h^2), one order higher than its interpolation error when the exact solution belongs to H^3(Ω). However, the interpolation error and consistency error of Carey element are of order O(h). It seems that the above special property has never been seen for other triangular elements for the second order problems. 展开更多
关键词 Consistency errors nonconforming finite element Quasi-Carey element
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A dynamic phasor estimation algorithm based on angle-shifted energy operator 被引量:1
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作者 JIN XiaNing WANG FuPing WANG ZanJi 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第6期1322-1329,共8页
Under dynamic conditions, the signals of power system have time-varying magnitude and frequency, which might lead to considerable errors for synchrophasor measurement. The traditional discrete Fourier transform (DFT) ... Under dynamic conditions, the signals of power system have time-varying magnitude and frequency, which might lead to considerable errors for synchrophasor measurement. The traditional discrete Fourier transform (DFT) based algorithms used in Phasor Measurement Unit (PMU) are hard to meet the requirements of measurement accuracy because of the existence of spectral leakage. A dynamic phasor measurement algorithm is proposed in this paper in which the input sampled data are considered as non-stationary signals with amplitude modulation-frequency modulation (AM-FM) form, and the measurement is achieved by AM-FM demodulation. An angle-shifted energy operator (ASEO) is used to extract the instantaneous amplitude and low pass differential filter is introduced for frequency estimation. Simulation results indicate that the proposed algorithm can effectively improve the phasor measurement accuracy and has very short response time for PMU under dynamic conditions. 展开更多
关键词 synchronous phasor measurement discrete Fourier transform (DFT) dynamic conditions energy operator
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