Adaptive Layout Partitioning for Dark Field Alternating Phase-Shift Mask Design

A new partitioning methodology is presented to accelerate 130nm and beyond large scale alternating phase shift mask(Alt PSM) design flow.This method deals with granularity self adaptively.Phase conflicts resolution approaches are described and strategies guaranteeing phase compatible during layout compaction are also discussed.An efficient CAD prototype for dark field Alt PSM based on these algorithms is implemented.The experimental results on several industry layouts show that the tool can successfully cope with the rapid growth of phase conflicts with good quality and satisfy lower resource consumption with different requirements of precision and speedup.

A Novel Multi-Functional Leakage Current Protector IC Design

A novel type of leakage current protector chip,implemented in the mixed-signal 0.6μm CMOS process,is presented. This chip has the advantages of low power dissipation （10mW）, accurate protection control based on digital response delay time and integration of multi-functions such as leakage current/over-voltage/over-load detection and protection,auto switch-on and so forth. Additionally, the chip is programmable to suit different three-level protection applications with a high anti-interference ability.

Top-Down Design of 260k Color TFT-LCD One-Chip Driver ICs

A top-down design methodology is proposed for the design of TFT-LCD one-chip driver ICs,and a 260k color, 176RGB× 220-dot TFT-LCD one-chip driver IC is successfully developed with silicon verification. This IC is a typical mixed-signal VLSI and is implemented by a 0.18μm HV CMOS process. The static power dissipation is about 5mW for 260k color display mode,and the settling time of the output grayscale voltages within 0.2% error is less than 26μs.

架设芯片设计与嵌入式系统开发的桥梁——大力发展第三方System Design House

解决我国集成电路的自主创新问题,要大力发展本地的IC设计企业,并在IC设计企业周围建立第三方System Design House,以构建IC设计与系统设计的桥梁。本文针对我国第三方System Design House的培育,提出了建设性意见,同时指出,SoC芯片和ASSP芯片都应纳入IC设计企业的主要产品范围。最后本文对单片机研发及应用现状进行综述,并给出发展我国单片机的建议。

An Arctic sea ice thickness variability revealed from satellite altimetric measurements

A modified algorithm taking into account the first year（FY） and multiyear（MY） ice densities is used to derive a sea ice thickness from freeboard measurements acquired by satellite altimetry ICESat（2003–2008）. Estimates agree with various independent in situ measurements within 0.21 m. Both the fall and winter campaigns see a dramatic extent retreat of thicker MY ice that survives at least one summer melting season. There were strong seasonal and interannual variabilities with regard to the mean thickness. Seasonal increases of 0.53 m for FY the ice and 0.29 m for the MY ice between the autumn and the winter ICESat campaigns, roughly 4–5 month separation, were found. Interannually, the significant MY ice thickness declines over the consecutive four ICESat winter campaigns（2005–2008） leads to a pronounced thickness drop of 0.8 m in MY sea ice zones. No clear trend was identified from the averaged thickness of thinner, FY ice that emerges in autumn and winter and melts in summer. Uncertainty estimates for our calculated thickness, caused by the standard deviations of multiple input parameters including freeboard, ice density, snow density, snow depth, show large errors more than 0.5 m in thicker MY ice zones and relatively small standard deviations under 0.5 m elsewhere. Moreover, a sensitivity analysis is implemented to determine the separate impact on the thickness estimate in the dependence of an individual input variable as mentioned above. The results show systematic bias of the estimated ice thickness appears to be mainly caused by the variations of freeboard as well as the ice density whereas the snow density and depth brings about relatively insignificant errors.

Sea ice thickness analyses for the Bohai Sea using MODIS thermal infrared imagery

Level ice thickness distribution pattern in the Bohai Sea in the winter of 2009-2010 was investigated in this paper using MODIS night-time thermal infrared imagery. The cloud cover in the imagery was masked out manually. Level ice thickness was calculated using MODIS ice surface temperature and an ice surface heat balance equation. Weather forcing data was from the European Centre for Medium-Range Weather Forecasts （ECMWF） analyses. The retrieved ice thickness agreed reasonable well with in situ observations from two off-shore oil platforms. The overall bias and the root mean square error of the MODIS ice thickness are -1.4 cm and 3.9 cm, respectively. The MODIS results under cold conditions （air temperature 〈 -10~C） also agree with the estimated ice growth from Lebedev and Zubov models. The MODIS ice thickness is sensitive to the changes of the sea ice and air temperature, in particular when the sea ice is relatively thin. It is less sensitive to the wind speed. Our method is feasible for the Bohai Sea operational ice thickness analyses during cold freezing seasons.

Observed and modelled snow and ice thickness in the Arctic Ocean with CHINARE buoy data

Sea ice and the snow pack on top of it were investigated using Chinese National Arctic Research Expedition （CHINARE） buoy data. Two polar hydrometeorological drifters, known as Zeno ice stations, were deployed during CHINARE 2003. A new type of high-resolution Snow and Ice Mass Balance Arrays, known as SIMBA buoys, were deployed during CHINARE 2014. Data from those buoys were applied to investigate the thickness of sea ice and snow in the CHINARE domain. A simple approach was applied to estimate the average snow thickness on the basis of Zeno temperature data. Snow and ice thicknesses were also derived from vertical temperature profile data based on the SIMBA buoys. A one-dimensional snow and ice thermodynamic model （HIGHTSI） was applied to calculate the snow and ice thickness along the buoy drift trajectories. The model forcing was based on forecasts and analyses of the European Centre for Medium-Range Weather Forecasts （ECMWF）. The Zeno buoys drifted in a confined area during 2003-2004. The snow thickness modelled applying HIGHTSI was consistent with results based on Zeno buoy data. The SIMBA buoys drifted from 81. 1°N, 157.4°W to 73.5°N, 134.9°W in 15 months during 2014-2015. The total ice thickness increased from an initial August 2014 value of 1.97 m to a maximum value of 2.45 in before the onset of snow melt in May 2015; the last observation was approximately 1 m in late November 2015. The ice thickness based on HIGHTSI agreed with SIMBA measurements, in particular when the seasonal variation of oceanic heat flux was taken into account, but the modelled snow thickness differed from the observed one. Sea ice thickness derived from SIMBA data was reasonably good in cold conditions, but challenges remain in both snow and ice thickness in summer.

Challenges and opportunities toward fully automated analog layout design

Realizing the layouts of analog/mixed-signal(AMS)integrated circuits(ICs)is a complicated task due to the high design flexibility and sensitive circuit performance.Compared with the advancements of digital IC layout automation,analog IC layout design is still heavily manual,which leads to a more time-consuming and error-prone process.In recent years,significant progress has been made in automated analog layout design with emerging of several open-source frameworks.This paper firstly reviews the existing state-of-the art AMS layout synthesis frameworks with focus on the different approaches and their individual challenges.We then present recent research trends and opportunities in the field.Finally,we summaries the paper with open questions and future directions for fully-automating the analog IC layout.

Sea ice thickness estimation in the Bohai Sea using geostationary ocean color imager data

A method to estimate the thickness of the sea ice of the Bohai Sea is proposed using geostationary ocean color imager （GOCI） data and then applied to the dynamic monitoring of the sea ice thickness in the Bohal Sea during the winter of 2014 to 2015. First of all, a model is given between the GOCI shortwave broadband albedo and the reflectance of each band with high temporal resolution GOCI data. Then, the relationship model between the sea ice thickness and the GOCI shortwave broadband albedo is established and applied to the thickness extraction of the sea ice in the Bohai Sea. Finally, the sea ice thickness extraction method is tested by the results based on the MODIS data, thermodynamic empirical models （Lebedev and Zubov）, and the in situ ice thickness data. The test results not only indicated that the sea ice thickness retrieval method based on the GOCI data was a good correlation （r2〉0.66） with the sea ice thickness retrieved by the MODIS and thermodynamic empirical models, but also that the RMS is only 6.82 cm different from the thickness of the sea ice based on the GOCI and in situ data.

Study on Edge Extraction Methods for Image-based Icing On-line Monitoring on Overhead Transmission Lines

A new method of measuring the icing thickness of transmission lines on-line is proposed in this paper.In this method,the pictures of transmission lines which are photoed by the camera on the iron tower are processed immediately to extract the edges of the transmission line conductor and transmission line insulators.The icing thickness can be gained by comparing the edges of the iced transmission line and the uniced one.Two icing image edge extraction methods are described in detail,that is,a method based on the combination of the wavelet transform and the floating threshold method and a method based on the combination of the optimal threshold method and the mathematical morphology transform.The icing images from the artificial climatic chamber and transmission lines are used to test the methods above.The results show that the method based on the wavelet transform and the floating threshold method does well in the extraction of relatively smooth edges,such as glaze icing on conductor and icing on the insulator;meanwhile,the method based on the optimal threshold method and the mathematical morphology transform does well in the edge extraction of icing on the conductor,especially the opaque rime icing on the conductor with complicated edges.

Effects of site conditions on earthquake ground motion and their applications in seismic design in loess region

The Loess Plateau is an earthquake prone region of China, where the effects of loess deposit on ground motion were discovered during the 2008 Wenchuan earthquake(Ms8.0) and the 2013 Minxian-Zhangxian earthquake(Ms6.6). The field investigations, observations, and analyses indicated that large number of casualties and tremendous economic losses were caused not only by collapse and damage of houses with poor seismic performance, landslides, but also amplification effects of site conditions, topography and thickness of loess deposit, on ground motion. In this paper, we chose Dazhai Village and Majiagou Village as the typical loess site affected by the two earthquakes for intensity evaluation, borehole exploration, temporary strong motion array, micro tremor survey, and numerical analysis. The aim is to explore the relations between amplification factors and site conditions in terms of topography and thickness of loess deposit. We also developed site amplification factors of ground motion for engineering design consideration at loess sites. The results showed that the amplification effects are more predominant with increase in thickness of loess deposit and slope height. The amplification mayincrease seismic intensity by 1 degree, PGA and predominant period by 2 times, respectively.

Arctic sea ice thickness changes in terms of sea ice age

In this study, changes in Arctic sea ice thickness for each ice age category were examined based on satellite observations and modelled results. Interannual changes obtained from Ice, Cloud, and Land Elevation Satellite（ICESat）-based results show a thickness reduction over perennial sea ice（ice that survives at least one melt season with an age of no less than 2 year） up to approximately 0.5–1.0 m and 0.6–0.8 m（depending on ice age） during the investigated winter and autumn ICESat periods, respectively. Pan-Arctic Ice Ocean Modeling and Assimilation System（PIOMAS）-based results provide a view of a continued thickness reduction over the past four decades. Compared to 1980 s, there is a clear thickness drop of roughly 0.50 m in 2010 s for perennial ice. This overall decrease in sea ice thickness can be in part attributed to the amplified warming climate in north latitudes. Besides, we figure out that strongly anomalous southerly summer surface winds may play an important role in prompting the thickness decline in perennial ice zone through transporting heat deposited in open water（primarily via albedo feedback） in Eurasian sector deep into a broader sea ice regime in central Arctic Ocean. This heat source is responsible for enhanced ice bottom melting, leading to further reduction in ice thickness.

Sea ice thickness and concentration in Arctic obtaining from remote sensing images

Based on the sea ice digital videos and photos along the investigation route in the Second Chinese National Arctic Research Expedition (CHINARE) during July and September, 2003, collections of sea ice thickness and concentration in the area of latitude range of 74.11°N - 79.56°N and longitude range of 144.17°W - 169.95°W are finished. This paper discusses the methods of obtaining ice/snow thicknesses from ship-side videos and ice concentrations from aerial photos, and illustrates the measures should be taken in analysis and in-situ investigation processes to improve the reliability of the parameters. The methods in this paper are somewhat universal and can be used in the research of Bohai Sea and Polar Regions sea ice.

Measuring Ice Thicknesses along the Red River in Canada Using RADARSAT-2 Satellite Imagery

The spring flood of 2009 in the Red River Valley was exacerbated with severe ice breakup and ice jamming. To assist ice jam mitigation by cutting and breaking up the river ice cover before the flood season and to support the operation of the Red River Floodway, Manitoba Water Stewardship is striving to model the occurrence of ice breakup and simulate the behaviour of ice jamming along the river. An important parameter in ice breakup forecasting is the ice thickness. RADARSAT-2 standard satellite images were collected along the course of the Red River in Manitoba during the 2009-2010 winter to help determine ice thicknesses along the river. Standard images can have transmit-receive polarizations in the horizontal-horizontal (HH) or horizontal-vertical (HV) configurations. Ice thickness measurements were taken in the field during the same time frame when the satellite passed over the Red River Valley. Good correlations were obtained between the HH-backscatter readings and the surveyed ice thicknesses. HV-backscatter readings correlate better with fresh snow depth measurements. Additionally, using same sensor incident angle and flight geometry allows ice thickening rate behavior over the course of the winter to be determined.

Regional characteristics of sea ice thickness in Canadian shelf and Arctic Archipelago measured by Ground Penetrating Radar

Ground Penetrating Radar （GPR） measurements of sea ice thickness including undeformed ice and ridged ice were carried out in the central north Canadian Archipelago in spring 2010. Results have shown a significant spatial heterogeneity of sea ice thickness across the shelf. The undeformed multi-year fast ice of （2.05±0.09） m thick was investigated southern inshore zone of Borden island located at middle of the observational section, which was the observed maximum thickness in the field work. The less thick sea ice was sampled across a flaw lead with the thicknesses of （1.05±0.11） m for the pack ice and （1.24±0.13） m for the fast ice. At the northernmost spot of the section, the undeformed multi-year pack ice was （1.54±0.22） m thick with a ridged ice of 2.5 to 3 m, comparing to the multi-year fast ice with the thickness of （1.67±0.16） m at the southernmost station in the Prince Gustaf Adolf Sea.

Towards a semi-empirical model of the sea ice thickness based on hyperspectral remote sensing in the Bohai Sea

Sea ice thickness is one of the most important input parameters for the prevention and mitigation of sea ice disasters and the prediction of local sea environments and climates. Estimating the sea ice thickness is currently the most important issue in the study of sea ice remote sensing. With the Bohai Sea as the study area, a semiempirical model of the sea ice thickness（SEMSIT） that can be used to estimate the thickness of first-year ice based on existing water depth estimation models and hyperspectral remote sensing data according to an optical radiative transfer process in sea ice is proposed. In the model, the absorption and scattering properties of sea ice in different bands（spectral dimension information） are utilized. An integrated attenuation coefficient at the pixel level is estimated using the height of the reflectance peak at 1 088 nm. In addition, the surface reflectance of sea ice at the pixel level is estimated using the 1 550–1 750 nm band reflectance. The model is used to estimate the sea ice thickness with Hyperion images. The first validation results suggest that the proposed model and parameterization scheme can effectively reduce the estimation error associated with the sea ice thickness that is caused by temporal and spatial heterogeneities in the integrated attenuation coefficient and sea ice surface. A practical semi-empirical model and parameterization scheme that may be feasible for the sea ice thickness estimation using hyperspectral remote sensing data are potentially provided.

Assessment and application of electromagnetic induction method to measure Arctic sea ice thickness

The electromagnetic induction method is widely used to measure sea ice thickness. Based on the electrical properties of sea ice and seawater, the method measures the apparent conductivity, which represents the conductivity of the half-space, and calculates the thickness of the sea ice. During the fourth Chinese National Arctic Research Expedition in summer 2010, an integrated electromagnetic induction system was set up on the icebreaker R/V XUE LONG to measure sea ice thickness along the ship＇s tracks to the north of the Chukchi Sea. The conductivities of sea ice, seawater, and brine were measured and a simple forward model was used to explain the effect of changes in those conductivities on the apparent conductivity over a horizontal layered structure. The results of this analysis indicated that when using the electromagnetic induction method to measure sea ice thickness, the conductivity of sea ice could be neglected and the conductivity of seawater could be treated as a constant. The ice distribution results derived from the electromagnetic induction method showed that the typical sea ice thickness was 160 cm and 90 cm during the outbound and the return legs of the voyage, respectively.

Sea ice thickness measurement in spring season in Bothnian Bay using an electromagnetic induction instrument

As an important component of the cryosphere,sea ice is very sensitive to the climate change.The study of the sea ice physics needs accurate sea ice thickness.This paper presents an electromagnetic-induction(EM) technique which can be used to measure the sea ice thickness distribution efficiently,and the successful application in Bothnian Bay.Based on the electromagnetic field theory and the electrical properties of sea ice and seawater,EM technique can detect the distance between the instrument and the ice/water interface accurately,than the sea ice thickness is obtained.Contrastive analysis of the apparent conductivity data obtained by EM and the value of drill-hole at same positions allows a construction of a transformable formula of the apparent conductivity to sea ice thickness.The verification of the sea ice thickness calculated by this formula indicates that EM technique is able to get reliable sea ice thickness with average relative error of only 12%.The statistic of all ice thickness profiles shows that the level ice distribution in Bothnian Bay was 0.4-0.6 m.

Correlations between IMC thickness and three factors in Sn-3Ag-0.5Cu alloy system

The effects of Ni content, soldering temperature and time on the IMC thickness in Sn-3Ag-0.5Cu and Sn-3Ag-0.5Cu-0.2Co alloys were researched using uniform design method and computer programs. For each alloy, the factors were divided into three levels in the experiment. Two correlative equations are given by regression. They indicate that the effects of three factors on the function are in the mutual and quadratic forms. And the analysis of variance shows the equations are sound and meaningful. Using the equations, it is easy to search, predict and control the IMC thickness. The existence of element Co accelerates the crystallization and growing up of IMC.

Nonlinear Analysis and Optimization of Shallow Shells of Variable Thickness

This paper is concerned with the nonlillear bending, stability and optimal design of revolution shallowshells with variable thickness. The problems are investigated by means of a modified iterative method proposedearlier by the author. Solutiolls for nonlinear bedding and stability problems of revolution shallow shells withvariable thickness, such as spherical and conical shells, are presented. Deflections and critical loads for stability arecalculated and the numerical results are plotted and given in tabular forms. It is showil that the equation determiningthe maximum deflection and the load coincides with the cusp catastrophe manifold. The optimal design of plates andshells, in Which the volullle is minimized or the critical load of shells is maximized, is investigated. When the volumeoftlle shell and the arch height of the shell are given, the variable thickness parameter can be solved. In addition, thispaper also gives tile constraint optimization of nonlinear bedding of circular plates.