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•Compact model of nanowire/nanosheet gate-all-around MOSFETs with quantum effects in focus.•Surface potential-based modeling formulations with energy quantization to characterize staircase behavior of capacitance.•Compact model implementation with Verilog-A, and compatible with circuit simulators for designs.•Model accuracy, scalability and convergence verified against numerical simulations as well as Si data.

Purpose: Congenital accessory navicular bone (ANB) is a common variant in the foot and is prone to cause several clinical symptoms. Wearing custom-made foot orthosis is considered a desirable option; however, there is limited evidence of its effectiveness. This study aims to report the mid-term effect of foot orthosis for symptomatic pediatric ANBs. Methods: School-age children with symptomatic ANBs combined with flexible flatfoot in the authors' institute were recruited and got custom-made foot orthosis treatment. They were followed up over 4 years. The general characteristics of these children were collected before treatment, including age, gender, and body mass index (BMI). The indicators of foot symptoms, including frequency and location of pain, visual analogue scale (VAS), arch index (AI), and hind foot valgus angle (HVA), were measured during pretreatment and at the last follow-up. Results: Twenty-seven children were recruited for this study. After 4 years of custom-made foot orthosis treatment, significant improvements showed in pain frequency, VAS, AI, and HVA (P< 0.001). Type II ANBs showed a higher pain index pretreatment (P< 0.001) and reduced after treatment (P< 0.001). Conclusion: Mid-term effect of custom-made foot orthosis is inspiring in clinical symptoms of pediatric congenital ANBs combined with flexible flatfoot and may be an optional nonoperative treatment.

This work proposes a statistical modeling approach for the artificial neural network (ANN)-based compact model (CM). The method of retaining part of the network features of the nominal device and further finetuning the network parameters (variational neurons) is found to accurately reproduce the static variation. A mapping from process variation to network parameters is derived by combining the proposed variational neuron selection algorithm and the backward propagation of variance (BPV) method. In addition, a secondary classification of the selected variational neurons is applied to model the fabrication-induced correlation between n- and p-type devices. The neural network-based statistical modeling approach has been well implemented and verified on the GAA simulation data and the 16nm node foundry FinFET, which indicates its great potential in modeling emerging and advanced device technology.

A generic compact modeling approach for emerging memories is developed in this work. State transitions, as well as the electric properties of each state, usually require separate efforts from a physics perspective. To accelerate memory modeling, a data-driven approach is explored with the recurrent Non-linear Auto Regressive with Exogenous inputs (NARX) network. The recurrent module captures the state transition dynamics, while a feedforward module is responsible for the non-linear states, such as high and low resistance states. The generic NARX-based model is demonstrated with high accuracy for emerging memories of different physics, such as resistive random-access-memory (ReRAM) and ferroelectric tunnel junction (FTJ). It is extendable to statistical modeling which is useful to cover memory variations. Circuit simulations are demonstrated with successful convergence, attributed to the capability of the NARX network and its compatibility with simulators.

The massive expansion of China's real estate sector has raised manufacturing wage through the channel of reallocating low-skilled labor from manufacturing sectors to the real estate sector. Using data of manufacturing firms in 35 major cities from 2000–2007, we find that the expansion of the real estate sector resulted in higher manufacturing wage. Additionally, we find that this positive effect was more pronounced among labor-intensive firms, among non-SOEs, and among firms in cities with a low development level of the labor market. By investigating the occupation choice of rural-to-urban migrant workers, we find that real estate expansion made migrant workers less likely to choose manufacturing jobs while more likely to choose construction jobs, which further confirms the labor reallocation story.

ABSTRACTThis study aims at finding out how China’s domestic and international timber markets interact with each other. Wald–Granger causality test, Geweke causality test and spectral Granger causality test were adopted to analyse daily data of domestic and imported logs and sawn timber prices. The results revealed that there was a significant Granger relationship between domestic and imported log markets and between domestic and imported sawn timber markets in both long and short terms, with a large proportion of instant feedback relationship. But the Granger tests for the relationship between the domestic log price and imported sawn timber price displayed a great difference. The Wald-Granger and Geweke causality test results showed that there was Granger relationship between the above two markets, but the result of spectral Granger causality test suggested that the domestic log price was not the Granger cause of the imported sawn timber price in the frequency domain of [0, π]. The results of empirical analysis proved a strong conductive relationship between the China’s domestic timber market and international market and displayed the complicated interaction between domestic and international timber markets which have strong policies implication for both government and enterprises in China.

Specialists on agricultural economics and economic development of China examine the dynamics of rural-to-urban migration in China from the perspective of migrant labor supply for the period of 1987–2008. Restricted by the hukou(registered permanent residence) system, rural households in China usually do not relocate from countryside to cities; only migrant workers travel back and forth. This circular pattern of migrant workers negatively influences their migration stability, thereby resulting in the instability of China’s migrant labor supply. By using panel data from rural household surveys in China, we examine migration persistence at both the household level and the individual level. We find that the extent of migration persistence was relatively low in China, suggesting that migrant labor supply was unstable. In addition, we find that labor counts, education level, and network effects improved households’ migration persistence. We also find that migration persistence was associated with individual characteristics, such as age, gender, and health conditions.

Lateral phase change memory (PCM) has attracted a lot of interest due to its simpler fabrication process and lower current. Researchers are trying to increase the storage capacity of lateral PCM. This paper proposed a novel super-lattice like (SLL) structure for lateral PCM to achieve multi-level storage. Lateral PCM with SLL structure incorporated with N-doped Sb70Te30 and ZnS-SiO2 has been fabricated and tested. Both tested static I-V curve and dynamic pulse mode R-V curve show multi states existing in the device. Electrical and thermal simulations have been done for this device. Simulation results show that different resistance level can be found in this device with different states of phase change bridges. With increasing periods of SLL structure, more states can be achieved.

To improve the stability and output voltage quality of inverter, an new repetitive control strategy for 400Hz Constant Voltage Constant Frequency (CVCF) inverter has been proposed . Based on active damping, this strategy damps the oscillations on the output LC filter of inverter under unload or light load. Using state-observer to weaken the impact of time delay in digital control, a 5.5 kW one-phase 400Hz inverter prototype by this strategy has been tested.The result shows that low THD (about 1.5%) with inductive loads and fast error convergence (2 fundamental periods) can be achieved by this strategy which can be demonstrated to be brief and effective.

AbstractIn this study, two deep convective cloud cases were analyzed in detail to study their initiation and evolution. In both cases, all deep convective clouds were posi-tioned at the rear of the cold front cloud bands and propagated backward. Satellite data showed that prior to initiation of the deep convective clouds, thermodynamic and moist conditions were favorable for their formation. In the morning, a deep convective cloud at the rear of cold front cloud band propagated backward, the outflow boundary of which created favorable conditions for initiation. An additional deep convective cloud cluster moved in from the west and interacted with the outflow boundary to develop a mesoscale convective system (MCS) with large, ellipse-shaped deep convective clouds that brought strong rainfall. The initiation and evolution of these clouds are shown clearly in satellite data and provide significant information for nowcasting and short-term forecasting.

Novel MgCl2-supported Ziegler-Natta (Z-N) catalysts prepared using a new one-pot ball milling method can effectively control the amounts of Ti-loading in the catalysts. Complex GPC data on polypropylene synthesized by these novel catalysts were analyzed using the method of fitting the molecular weight distribution (MWD) curves with a multiple Flory-Schulz function. It was found that multiple active centers exist in these novel catalysts. Detailed study of the effects of the Ti-loadings in the catalysts on the distribution of the active centers showed that the Ti-loadings in the novel MgCl2-supported Z-N catalysts might affect the proportion of each type of active centers; and might be the main factor responsible for the effect of the Ti-loadings on the microstructure, the molecular weight and molecular weight distribution width of the resultant polymer, the catalytic activity and polymerization kinetics.

Danckwert's method was used to determine the specific interfacial area,a, and the individual mass transfer coefficient,kL, during absorption of CO2in a bubble column with an anionic surfactant in the carbonate-bicarbonate buffer solution and NaAsO2as catalyst, the presence of which decreases the specific interfacial area and the individual mass transfer coefficient. The specific interfacial area and the individual mass transfer coefficient increase with increasing superficial gas velocity. The specific interfacial area decreases whereas the individual mass transfer coefficient increases with increasing temperature. The results of experiments were used to determine the dependence ofa, kL, andkLaon the surface tension, the temperature of the absorption phase, and the superficial velocity of the gas. The calculated results from the correlation were found to be within 10% deviation from the actual experimental results.

Objective: To explore the characteristics of acupoint selection in the treatment of apoplexy.Method: This paper reviews and analyzes the ancient and current medical literature, and then summarizes the characteristics of acupoint selection in treating apoplexy.Results: Four characteristics are presented: the acupoints on the head are mostly used; the acupoints are principally selected according to the course of nerves; the acupoints of the yang meridians are usually selected; the special acupoints and empirical acupoints are often combined.Conclusion: Above principles may be adopted in the selection of acupoints to treat apoplexy.

The effect of bilateral salpingectomy on ovarian function was studied in the rabbit. Nine rabbits underwent a microsurgical removal of both fallopian tubes, and nine other rabbits underwent sham operations. Four weeks after surgery the rabbits were mated, and the number of ovulation sites were recorded 18 hours after mating. Serum progesterone (P) levels were also determined prior to the operation and at 6 days and 8 days after mating. Eight days after mating the ovaries were recovered, and the corpora lutea were removed and weighed. The mean number and weights of corpora lutea as well as serum P levels did not differ significantly between the groups. These findings suggest that the absence of fallopian tubes has no effect on subsequent ovulatory function in this animal model.

Serum antibody responses to shigella lipopolysaccharide (LPS) and invasion plasmid-coded antigens (Ipa) were studied in 74 Swedish patients with culture verified bacillary dysentery using class-specific enzyme immunoassay (EIA). Anti-LPS responses were found in 80% and 79% serum samples, respectively, from S. flexneri and S. sonnei infected patients and anti-Ipa responses in 60% and 43%, respectively. The mean anti-Ipa IgG antibody titres in S. flexneri infected patients remained high for 4-6 months after onset while the anti-LPS IgG antibody titres had dropped to normal levels. The specificity of EIA for shigella Ipa was 90% and for S. dysenteriae, S. flexneri and S. sonnei LPSs it varied between 84% and 90%. No close correlations between the anti-LPS and anti-Ipa antibody responses were observed indicating that they may be differently regulated. The dynamics of the serum antibody responses indicates that an anti-LPS response is a good indicator of a recent shigella infection and an anti-Ipa IgG response a good indicator of a previous infection.

As selenium transfer reagents, arylselenoamides react with a variety of alkyl halides in ethanol under mild conditions to give dialkyl diselenides in excellent yields. Similarly, alkyl halides treated with selenourea form dialkyl diselenides. The possible mechanism is discussed.

Spectral changes in fluorescence of phycobilisomes (PBS) of A. variabilis treated with proteinase K were studied at room and liquid nitrogen temperature. In control PBS, the relative yield of 77 K fluorescence of F686 was very high, and those of F655 and F666 were low. In PBS treated with proteinase K for less than 1 h, F686 decreased, and F655 and F666 increased. In PBS treated with proteinase K for 2 h, F655 was the main peak of fluorescence emission, F686 was the second peak, the fluorescence emission peak of F666 disappeared. In PBS treated with proteinase K for more than 8 h, F655 showed only one fluorescence emission peak.

The Bering sea is susceptible to ocean acidification driven by both human activities (anthropogenic CO2) and distinctive natural processes. To assess the situation of ocean acidification, we investigated the spatial variability of aragonite saturation states (ΩAr) in July 2010 during the 4th Chinese National Arctic Research Expedition (CHINARE). The surface waters were all oversaturated with respect to aragonite (ΩAr> 1) due to high biological removal, and ΩArranged from 1.43 to 3.17. The relatively low ΩArvalues were found in the western Bering Strait and eastern nearshore region of the Bering Sea Shelf, which were associated with the upwelling and riverine input, respectively. In the subsurface, the ΩArdecreased to generally low saturation states and were observed to be strongly undersaturated (ΩAr< 1) in the bottom waters with a lowest value of 0.45, which might be caused by remineralization. However, unlike prior studies, the low ΩArvalues in the shallow nearshore region were still above the saturation horizon throughout the water column, which were probably counteracted by high local primary production. In the context of climate change and increasing anthropogenic CO2absorption, the suppression and undersaturation of ΩArin the Bering Sea are not only attributed to the natural processes but also the accumulation of anthropogenic CO2.

Lateral phase change memory (PCM) has attracted a lot of interest due to its simpler fabrication process and lower current. Researchers are trying to increase the storage capacity of lateral PCM. This paper proposed a novel super-lattice like (SLL) structure for lateral PCM to achieve multi-level storage. Lateral PCM with SLL structure incorporated with N-doped Sb70Te30and ZnS-SiO2has been fabricated and tested. Both tested static I-V curve and dynamic pulse mode R-V curve show multi states existing in the device. Electrical and thermal simulations have been done for this device. Simulation results show that different resistance level can be found in this device with different states of phase change bridges. With increasing periods of SLL structure, more states can be achieved.

The selective etching of n-Al0.3Ga0.7As with respect to p+-GaAs is useful for the fabrication of AlGaAs/GaAs heterojunction bipolar transistors (HBTs). The KI/I2/H2O/H2SO4etching solution was found to be superior to the KI/I2/H2O solution in terms of selectivity. The selectivity could be furthered improved by aging the etching solution for 3 days and by lowering the temperature from room temperature to the ice point. The best selectivity achieved was 330 with etch rates of 0.165 µ m/min and 0.0005 µ m/min for Al0.3Ga0.7As and GaAs respectively for a stabilized KI/I2/H2O/H2SO4at an etching temperature of 3° C.

Phase change random access memory (PCRAM) is the most promising candidate for the next-generation nonvolatile memory. Recently, elevated-confined PCRAM using an elevated metal column was proposed as a promising approach to achieve lower RESET current. This paper studied the writing strategy to enhance the endurance of elevated-confined PCRAM through both experiment and simulation. Elevated-confined PCRAM incorporating Ge2Sb2Te5were fabricated and tested. The overwriting test showed that the failure mode of elevated-confined PCRAM was stuck SET. As diffusion, which is the main reason for stuck SET, is highly dependent on working temperature, writing strategies are investigated to minimize the over-heating in elevated-confined PCRAM. From the simulation results, it is found that RESET pulse width is more effective than RESET pulse amplitude in controlling of over-heating. The testing results showed that the endurance cycles can be improved from $10^{6}$ to $10^{8}$ with shorter and lower RESET pulse, which is consisted with simulation results.

The dependence of the optical and thermal characteristics of phase-change optical disks on the multilayer disk structure was analyzed and simulated. Using the integrated software developed, a phase-change optical disk structure for a blue laser is designed with both optical and thermal considerations, and a suitable disk structure is proposed. Based on the designed disk structure, writing and rewriting processes are simulated, and the results are satisfactory.