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Background: Hepatocellular carcinoma (HCC) is the most common primary malignant tumor in the liver. Partial hepatectomy is one of the most effective therapies for HCC but suffer from the high recurrence rate. At present, the studies of association between clinical outcomes and CT features of patients with HCCs undergoing partial hepatectomy are still limited. The purpose of this study is to determine the predictive CT features and establish a model for predicting relapse or metastasis in patients with primary hepatocellular carcinomas (HCCs) undergoing partial hepatectomy.Methods: The clinical data and CT features of 112 patients with histopathologically confirmed primary HCCs were retrospectively reviewed. The clinical outcomes were categorized into two groups according to whether relapse or metastasis occurred within 2 years after partial hepatectomy. The association between clinical outcomes and CT features including tumour size, margin, shape, vascular invasion (VI), arterial phase hyperenhancement, washout appearance, capsule appearance, satellite lesion, involvement segment, cirrhosis, peritumoral enhancement and necrosis was analyzed using univariate analysis and binary logistic regression. Then establish logistic regression model, followed by receiver operating characteristic (ROC) curve analysis.Results: CT features including tumor size, margin, shape, VI, washout appearance, satellite lesion, involvement segment, peritumoral enhancement and necrosis were associated with clinical outcomes, as determined by univariate analysis (POR=6.41 and 10.92 respectively). The logistic regression model was logit(p)=-1.55+1.86 margin +2.39 VI. ROC curve analysis showed that the area under curve of the obtained logistic regression model was 0.887(95% CI：0.827-0.947).Conclusion: Patients with ill-defined margin or VI of HCCs were independent risk predictors of poor clinical outcome after partial hepatectomy. The model as logit(p)= -1.55+1.86 margin +2.39 VI was a good predictor of the clinical outcomes.

Background To investigate whether the relative computed tomography (CT) value (rCT) of adjacent pancreatic parenchyma can distinguish focal‐type autoimmune pancreatitis (fAIP) from pancreatic ductal adenocarcinoma (PDAC). Methods A total of 13 patients with fAIP and 20 patients with PDAC were included in this study. The rCT was calculated as the ratio of the CT value of adjacent pancreatic parenchyma to that of muscle. The diagnostic performance of rCT for discriminating fAIP from PDAC was evaluated using receiver operating characteristic (ROC) analysis. Results Both fAIP and PDAC presented hyper‐fibrosis histologically and delayed enhancement on CT examination. Moreover, the pancreatic parenchyma of fAIP presented serious inflammation. The mean rCT of the parenchyma was significantly lower in fAIP than in PDAC in all phases. The best diagnostic performance of the rCT value was found in the pancreatic phase, with an area under the ROC curve of 0.912, while the areas under the ROC curve of the portal and delayed phases were 0.812 and 0.754, respectively. The optimal cut‐off value for distinguishing fAIP from PDAC was 1.62 in the pancreatic phase. Conclusions The rCT of the pancreatic parenchyma during the pancreatic phase may be a feasible CT feature for differentiating fAIP from PDAC., Similar imaging features such as regional enlargement of the pancreas and delayed enhancement became a big challenge to differentiate focal‐type autoimmune pancreatitis (fAIP) from PDAC. In this study, we found that the pancreatic parenchyma of fAIP presented severe inflammation. Moreover, the mean relative computed tomography values of the pancreatic parenchyma were lower in fAIP than that in PDAC in all phases.

Facial makeup transfer is a hot research field in computer vision, aiming to transfer the reference face's makeup style to the non-makeup face. In the existing research, we can use to combat the loss to keep the identity information of the face consistent before and after the makeup transfer, but because the input face sometimes has a massive deflection and expression action, which seriously affects the effect of makeup transfer. This paper proposed a face makeup transfer framework based on multi-scale feature loss. Our model is composed of a generator, discriminator, and multi-scale discriminator. The reference makeup and the non-makeup face are input into the generator at the same time. The generator will output the non-makeup face after makeup, which contains the input non-makeup face's identity information and the reference makeup style. To enhance the robustness of the makeup result on the network and improve the effect of makeup on the network, the output makeup face and the input non-makeup face are input into the multiscale discriminator to calculate the feature loss. The multi-scale discriminator takes the pixel multiplication of the semantic segmentation image of the makeup face and the non-makeup face as the input 1 of the multi-scale discriminator, and the pixel multiplication of the non-makeup face and its semantic segmentation as the input 2 of the multi-scale discriminator, and then calculates the feature loss of the two inputs after passing through the multi-scale discriminator. In the calculation process, the feature loss can constrain the pixel differences of different semantic segmentation, which can restrain the shadow and makeup overflow caused by angle deflection and facial expression in makeup transfer. The experimental results show that this paper's experimental method achieves a better effect of makeup transfer than the existing experimental methods.

OBJECTIVE. The purpose of our study was to retrospectively characterize the CT and MRI features of primary intrahepatic lymphoepithelioma-like cholangiocarcinoma (LELCC). MATERIALS AND METHODS. Eleven patients (10 women and one man; age range, 30-63 years) with 11 pathologically proven LELCCs were enrolled retrospectively from April 2016 to December 2018. Triphasic enhanced images were obtained of all patients: MR images of five patients, CT images of five patients, and both CT and MR images of one patient. The clinical data and CT and MRI findings were reviewed. RESULTS. All LELCC cases were associated with Epstein-Barr virus (EBV) infection. Eight of the 11 patients had hepatitis B virus (HBV) infection. The tumor diameter ranged from 1.1 to 8.7 cm. All tumors were well defined with a smooth or lobulated margin. A cystic area was noted in two of the 11 tumors. After the administration of contrast material, the tumors showed homogeneous (n = 7) or heterogeneous (n = 4) hypervascular arterial enhancement and gradual washout, delayed central scar or irregular enhancement (n = 9), delayed circular thin or incomplete pseudocapsule enhancement (n = 7), and homogeneous hypointensity in the hepatobiliary phase (n = 2). No cirrhosis, focal dilatation of intrahepatic ducts, or satellite nodules were detected. Lymphadenopathy were detected in four patients, appearing as hypervascular enhancement and no necrosis (even in multiple nodes > 3 cm) or as moderate peripheral enhancement and necrosis. CONCLUSION. A liver mass in a middle-aged woman with EBV and HBV infection that appears on CT and MRI to have a well-defined boundary and a combination of hypervascularity, washout, delayed intratumoral enhancement, or pseudocapsule enhancement may suggest an imaging diagnosis of primary LELCC. More cases are needed to better understand this disease.

Background Infection prevention and control (IPC) measures are crucial to combat the COVID-19 pandemic. This study aimed to explore the levels and determinants of HCWs’ IPC behaviors based on the theoretical domains framework (TDF), which has been shown to be effective in guiding behavior change. Methods A cross-sectional survey was conducted in Wuhan, China in January 2020. Self-reported hand hygiene and droplet isolation behaviors (including the use of masks, gloves, goggles and gowns) were set as dependent variables. TDF domains and HCWs’ characteristics were independent variables. Negative binomial regression analyses were performed to explore their relationships. Results HCWs reported good IPC behaviors, while the compliance with goggle and gown use was relatively low (below 85%). Environmental context and resources domain was significantly related to hand hygiene (β = 0.018, p = 0.026), overall droplet isolation behaviors (β = 0.056, p = 0.001), goggle (β = 0.098, p = 0.001) and gown use (β = 0.101. p p = 0.005) and gown use (β = 0.053, p = 0.013). Emotion domain was a predictor of overall droplet isolation behaviors (β = 0.043, p = 0.016), goggle (β = 0.074, p = 0.026) and gown use (β = 0.106, p p = 0.029) and gown use (β = 0.039, p = 0.035). HCWs in high-risk departments had better behaviors of gown use (β = 0.158, p = 0.032). HCWs who had encountered confirmed or suspected patients reported worse behaviors of goggle (β = − 0.127, p = 0.050) and gown use (β = − 0.153, p = 0.003). Conclusions Adequate personal protective materials and human resources, education and training, as well as supervision and role model setting are necessary to improve IPC behaviors regarding the COVID-19 pandemic.

Background: Irrational use of antimicrobial agents for gastrointestinal diseases deserves attention, but corresponding antimicrobial stewardship programs (ASPs) are generally not a priority for managers. We conducted this study to evaluate the effectiveness of multifaceted pharmacist-led (MPL) interventions in the gastroenterology ward (GW) to provide evidence for the efficacy of ASPs in a non-priority department. Methods: This was an interventional, retrospective study implemented in China. The MPL intervention lasting 1.5 years involved daily ward rounds with physicians, regular review of medical orders, monthly indicator feedback, frequent physician training, and necessary patient education. Data on all hospitalized adults receiving antibiotics was extracted from the hospital information system over a 36-month period from January 2016 to December 2018. Segmented regression analysis of interrupted time series was performed to evaluate the effect of the MPL interventions (started in July 2017) on antibiotic use and length of hospital stay, which was calculated monthly as analytical units. Results: A total of 1763 patients receiving antibiotics were enrolled. Segmented regression models showed descending trends from the baseline in the intensity of antibiotic consumption (coefficient = -0.88, p = 0.01), including a significant decline in the level of change of the proportion of patients receiving combined antibiotics (coefficient = -9.91, p = 0.03) and average length of hospital stay (coefficient = -1.79, p = 0.00), after MPL interventions. The MPL interventions led to a temporary increase in the proportion of patients receiving antibiotics (coefficient = 4.95, p = 0.038), but this was part of a declining secular trend (coefficient = -0.45, p = 0.05). Conclusion: The MPL interventions led a statistically significant decline in the number of patients receiving antibiotics, the antibiotic consumption and the average hospital stay post-intervention compared to the pre-intervention phase of the study. Health policymakers should actively practice MPL interventions by clinical pharmacists in ASPs in those departments that are not included in priority management.

To explore the relationship between osteosclerotic changes and chemotherapy response in non-small-cell lung cancer (NSCLC) patients with bone metastases (BM). Fifty-two NSCLC patients with BM were enrolled from 1 January 2010–31 June 2015 and divided into two groups based on their CT features: an osteosclerotic change (OC) group and a no-osteosclerotic change (NOC) group. The disease control rate (DCR) was evaluated, and progression-free survival (PFS) was analysed using Kaplan-Meier curves. Univariate and multivariate Cox regression analyses were performed to analyse the factors that could affect PFS. Osteosclerotic changes were observed in 35/52 patients. The median interval when osteosclerotic changes occurred was 2 months (range 1–3 months) after chemotherapy. The OC group had a significantly higher 3-month DCR than the NOC group (p < 0.001). The OC group had a higher 1-year PFS rate than the NOC group (1-year PFS: 74.9% vs. 30.2%, p < 0.001). Univariate Cox regression analysis indicated that pathological subtype (HR = 4.419; 95% CI = 1.635–11.941, p = 0.003) and osteosclerotic changes (HR = 0.199; 95% CI = 0.083–0.477, p < 0.001) were significant predictors of PFS. Early osteosclerotic changes predict chemotherapy response in NSCLC patients with BM. • Osteosclerotic changes were prevalent CT features after chemotherapy in NSCLC patients. • Osteosclerotic changes were positively related to increased 3-month DCR. • Osteosclerotic changes were positively related to increased 1-year PFS rate.

To investigate the predictive clinical and imaging factors associated with pulmonary metastasis in pulmonary nodules (PNs) ≤10 mm in patients with primary extrapulmonary malignancy (PEPM) on initial CT as well as the inter-nodular imaging features in the non-solitary PNs patients, to make a more reliable diagnosis and appropriate management of the PNs at an earlier stage after detection. 161 patients with PNs ≤10 mm were reviewed from April 2013 to December 2013. The nature of PNs were determined on the interval change in imaging features on serial CT images (158 patients) and histologically proven (three patients). Independent predictors of changed PNs on initial CT were examined by multivariate regression analysis. 36.6% of patients developed interval change in nodules size. The average interval of the first change was 65.0 days (29–144 days). Tumor staging of III (P = 0.011) and IV (P

Background COVID-19 arise global attention since their first public reporting. Infection prevention and control (IPC) is critical to combat COVID-19, especially at the early stage of pandemic outbreak. This study aimed to measure level of healthcare workers’ (HCW’) self-reported IPC behaviors with the risk of COVID-19 emerges and increases. Methods A cross-sectional study was conducted in two tertiary hospitals. A structured self-administered questionnaire was delivered to HCWs in selected hospitals. The dependent variables were self-reported IPC behavior compliance; and independent variables were outbreak risk and three intent of infection risk (risk of contact with suspected patients, high-risk department, risk of affected area). Chi-square tests and multivariable negative binomial regression models were employed. Results A total of 1386 participants were surveyed. The risk of outbreak increased self-reported IPC behavior on each item (coefficient varied from 0.029 to 0.151). Considering different extent of risk, HCWs from high-risk department had better self-reported practice in most IPC behavior (coefficient ranged from 0.027 to 0.149). HCWs in risk-affected area had higher self-reported compliance in several IPC behavior (coefficient ranged from 0.028 to 0.113). However, HCWs contacting with suspected patients had lower self-reported compliance in several IPC behavior (coefficient varied from − 0.159 to − 0.087). Conclusions With the risk of COVID-19 emerges, HCWs improve IPC behaviors comprehensively, which benefits for better combat COVID-19. With the risk (high-risk department and affected area) further increases, majority of IPC behaviors achieved improvement. Nevertheless, under the risk of contact with suspected patients, HCWs show worse IPC behaviors. Which may result from higher work load and insufficient supplies and resources among these HCWs. The preparedness system should be improved and medical assistance is urgently needed.

The development of the millimeter-level wireless magnetic actuated robot has provided the possibility for the development of endoscope. In the modern medical system, drugs enter the human body by oral administration and reach the intestinal tract through the esophagus and stomach. If the lesion is located in the gastrointestinal tract, most of the drugs have been absorbed by other parts, and the efficacy is not maximized. In this paper, a structure design of multi-capsule robotic group fixed-point drug release based on Ferro fluid is proposed. The robots group is composed of a front robot and a rear robot, each of which is composed of the robotic body, permanent magnet and Ferro fluid. Permanent magnets are fixed inside of the robot and the rotating electromagnetic field generated by the Helmholtz coils actuates the robots to move forward. Each robot is injected with Ferro fluid, and a clamping force can be generated between the two robots by applying an external magnetic field. The experimental results show that the capsule robots group can reach the designated location for drug release by rotating magnetic field and external permanent magnet.

Magnetic driven microrobots, which travel in water or other aqueous mediums, have provided great potential and are urgently demanded in the biomedical field. Many advances in the self-propulsion mechanism suggest that these small robots are very suitable for using in channels. However, the spatial limitations of the internal environment and the size constraint of the millimeter robots are huge challenges in the medical applications. In this paper, a driven approach for multiple capsule robots with screw structure and propeller structure is explored. The two robots can be controlled by a rotational electromagnetic field generated by two pairs of three-axis Helmholtz coils. Mechanical model is set and hydrodynamics of multiple capsule robots is analyzed. Based on the nonoverlapping driven frequencies, these robots are able to set off at different start frequencies and stop at different step-out frequencies. The verified experiments are conducted in pipe filled with water. Different movements such as docking and release are verified. The experimental results indicate that the multiple capsule robots would be a promising way to accomplish multifunctional manipulation and perform complex surgeries.

Wireless capsule robots, traveling in water or other aqueous mediums, have been urgently demanded in biomedical field. Many advancements to self-propelling mechanisms have shown that these small scale robots are well-suited for use in channels. However, the space constraint of the internal environment of body cavities and the size limitation of the millimeter scale robots are great challenges in medical application. In this paper, a driven approach based on different start frequencies is proposed for a multiple modular capsule robot moving in pipe. The robot is designed with two modules. Composing driven permanent magnets (DPMs), these modules can be steered by rotational electromagnetic field generated by Helmholtz coils. More specifically, the multiple modular capsule robot forms new construction via docking mechanism. Joint permanent magnets (JPMs) are fabricated on both sides in the robot body. Dynamic model is utilized to research the start frequencies. Based on the different geometrical parameters of screw structure, these modules are able to set off at different start frequencies. The experiments are conducted in pipe filled with water to verify different motions such as combination and separation. The experimental results indicate that the multiple modular capsule robot would be a promising way to perform complex surgeries and accomplish multifunctional operations.

To investigate the optimal monochromatic energy for artifacts reduction from 125I seeds as well as image improvement in the vicinity of seeds on monochromatic images with and without metal artifacts reduction software (MARS) and to compare this with traditional 120-kVp images, so as to evaluate the application value of gemstone spectral imaging for reducing artifacts from 125I seeds in liver brachytherapy. A total of 45 tumors from 25 patients treated with 125I seed brachytherapy in the liver were enrolled in this study. Multiphasic spectral computed tomography (CT) scanning was performed for each patient. After a delay time of 15 s of portal vein phase, a traditional 120-kVp scan was performed, focusing on several planes of 125I seeds only. The artifact index (AI) in the vicinity of seeds and the standard deviation (SD) of the CT density of region of interest in the outside liver parenchyma were calculated. Artifact appearance was evaluated and classified on reconstructed monochromatic S and 120-kVp images. Image quality in the vicinity of seeds of three data sets were evaluated using a 1–5 scale scoring method. The Friedman rank-sum test was used to estimate the scoring results of image quality. The greatest noise in monochromatic images was found at 40 keV (SD = 27.38, AI = 206.40). The optimal monochromatic energy was found at 75 keV, which provided almost the least image noise (SD = 10.01) and good performance in artifact reduction (AI = 102.73). Image noise and AI reduction at 75 keV was decreased by 63.44 and 50.23 %, compared with at 40 keV. Near-field thick artifacts were obvious in all 45 lesions, in 120-kVp images, and 75-keV images, but basically reduced in 75 keV MARS images and artifacts completely invisible in 7 lesions. The number of diagnosable images (score ≥3) was significantly more in the 75-keV MARS group (28/45), and the 75-keV group (22/45) than in the 120-kVp group (11/45) (p

Demand-side energy management is used for regulating the consumers’ energy usage in smart grid. With the guidance of the grid’s price policy, the consumers can change their energy consumption in response. The objective of this study is jointly optimizing the load status and electric supply, in order to make a tradeoff between the electric cost and the thermal comfort. The problem is formulated into a nonconvex optimization model. The multiplier method is used to solve the constrained optimization, and the objective function is transformed to the augmented Lagrangian function without constraints. Hence, the Powell direction acceleration method with advance and retreat is applied to solve the unconstrained optimization. Numerical results show that the proposed algorithm can achieve the balance between the electric supply and demand, and the optimization variables converge to the optimum.

Interest is growing in the interventional surgery training system used before the treatment of vessel diseases. As one of the elementary component of the simulator, an accurate reconstruction of blood vessel obtaining from cross-sectional images is ugly needed. Digital Subtraction Angiography (DSA) data is used as a criterion for reconstruction result of blood vessel. In this paper, an improved threshold method is proposed to segment blood vessel from medical images. Firstly, with optimization characteristic, the genetic algorithm is used to determine the pre-segmentation greyscale from best histogram entropy. Secondly, we enlarge greyscale around the best greyscale to adjust image intensity value which can greatly singularize the region of interest. And then, classical threshold method (Otsu algorithm) is used to determine the best threshold value which can separate blood vessel from background. To test the improved method, comparative trial was set to testify the improvement. Finally, a series of DSA images were obtained to demonstrate this method and the final experimental results showed the effectiveness of the improved method.

This paper proposes an economic dispatch strategy for the electricity system with one generation company, multiple utility companies and multiple consumers, which participate in demand response to keep the electricity real-time balance. In the wholesale markets, multiple utility companies will commonly select a reliable agent to negotiate with the generation company on the wholesale price. It is challengeable to find a wholesale price to run the electricity market fairly and effectively. In this study, we use the multiple utility companies’ profits to denote the utility function of the agent and formulate the interaction between the agent and the generation company as a bargaining problem, where the wholesale price was enforced in the bargaining outcome. Then, the Raiffa–Kalai–Smorodinsky bargaining solution (RBS) was utilized to achieve the fair and optimal outcome. In the retail markets, the unfavorable disturbances exist in the power management and price when the consumers participate in the demand response to keep the electricity real-time balance, which motivates us to further consider the dynamic power management algorithm with the additive disturbances, and then obtain the optimal power consumption and optimal retail price. Based on the consumers’ utility maximization, we establish a price regulation model with price feedback in the electricity retail markets, and then use the iterative algorithm to solve the optimal retail price and the consumer’s optimal power consumption. Hence, the input-to-state stability condition with additive electricity measurement disturbance and price disturbance is given. Numerical results demonstrate the effectiveness of the economic dispatch strategy.

Mass Spring Model (MSM) and Finite Element Method (FEM) are two basic methods for soft model deformation simulation. However, MSM has a high computation efficiency but low accuracy which is only a coarse approximation of the real biological soft tissue while FEM is inverse on the two sides. To achieve realistic and real-time simulation at the same time, in this paper, we proposed an improved non-linear elastic tensor-mass modelling method, which realizes fast computation of non-linear mechanical deformations, and it is suitable for simulating the hollow biological tissue surface. Based on the tensor-mass concept, we applied the tensors of triangles to the surface vessel model, which is distinguished from the current study of tetrahedral tensors while simulating solid tissue, such as liver. Also, we applied an extension of an efficient implicit numerical analytical method for the simulation. Moreover, we introduced a haptic force feedback device for interactions between the vessel model and the virtual medical instrument which improves the realism of the simulation. A set of experiments, including the interactive deformation of the physical vessel model, and the stress-strain data analyses of different nodes and a single node, were conducted to validate the realism, accuracy, steadiness of the TMM model during the simulation. The simulation results showed high efficiency and real time performance over 91 fps which is about 30% higher than the current realistic simulation method in the training system.

To retrospectively evaluate risk factors related to incomplete computed tomography (CT)-guided radiofrequency (RF) ablation of metastatic and primary lung tumors.This study included 93 patients with 147 tumors: 70 men, 23 women; median age 54 y (range, 19-81 y); 24 cases of primary lung tumors, 69 cases of metastases; average largest diameter of tumors, 1.8 cm ± 1.2 (range, 0.3-6.0 cm). Local efficacy was evaluated based on CT follow-up scans. Complete ablation rates (CARs) for tumors were calculated according to several variables; independent risk factors for local tumor progression (LTP) were examined by binary logistic regression analysis.CAR of tumors was 60.54% within first 6 months after lung RF ablation; median interval of LTP was 1.5 months (mean, 1.3 months ± 1.0; range, 0 days to 3 months). Compared with tumors3 cm, CAR of tumors ≤ 3 cm was significantly higher (68.55% vs 17.39%, P.001). CAR of tumors with complete ablation margin (AM) was dramatically higher compared with tumors with incomplete AM (74.77% vs 16.67%, P.001). Among tumors with complete AM, CAR of tumors with shortest distance between outer edge of tumor and AM (ablative margin D) ≥ 5 mm was compared with tumors with ablative margin D 1-4 mm (85.96% vs 62.96%, P = .005). Multivariate regression analysis showed that lobulation and/or spicules, contact with blood vessels, and ablative margin D5 mm were independent risk factors for incomplete lung RF ablation. LTP was likely to develop at the edge of ablated lesions and especially the site of incomplete AM or shortest AM.RF ablation for lung cancers should be individualized based on tumor size, morphology, and tumor type to obtain an adequate AM.

In order to suppress LCL inherent resonance and grid background harmonic problems, virtual impedance control based on capacitor current feedback and grid voltage feedforward control strategies are typically introduced in grid-connected inverters. However, the inverter control strategy can't make the system operate stably in a weak grid. By analyzing the characteristics of voltage and current in weak grid, this paper shows grid-inverter's stability margins significantly reduce due to the grid impedance. The margins of stability get smaller when the grid impedance gets larger, and at last results to an unstable system. Based on the distribution of system's zero-poles, a strategy with a reconstructed regulator is proposed to improve the system's stability margins and optimize the grid current waveform. Finally, the effectiveness of the proposed strategy is tested through simulations and experiments. And the inverter system can operate stably within a large grid impedance range.

This article detailed introduction things of Internet technology in domestic and foreign research condition, trend of development as well as research goal and significance. Elaborated the things of Internet concept, the principle and the characteristic, then from home automation(HA), intelligent medical service(IM), intelligent transportation(ITS), intelligent electrical network (SPG), modern agriculture (MA) and intelligent Logistics (IL)from the intelligence aspects and so on intelligent physical distribution separately introduced the question which the things of Internet application, simultaneously also extracted the networking to face the core technologies which challenges and urgently awaits to be solved, finally carried on the analysis and the forecast to the industrial production development.

A fusion decision algorithm of hydrophobic level is proposed according to the analysis of D-S evidence theory. The area, shape and analysis of hydrophobicity are considered as the characteristics of the three classifiers, and then the basic probability assignment function is calculated by adopting fuzzy rules. The results of the three classifiers are estimated using the composite law of D-S evidence theory. Experiment results show that the method can improve the accuracy and reliability of hydrophobic level identification effectively, and meet the needs of on-line hydrophobic monitoring.

A new control approach based on Proportional Complex Integral control for grid-connected current is presented in this paper. The working principle is analyzed, parameter design and implementation method for PCI control are given. this controller is different from traditional PI control, PCI control can introduce the infinite gain at the fundamental frequency, so it not only can eliminate steady-state amplitude and phase errors. but also grid-connected current is not disturbed by Network Voltage at the fundamental frequency completely, but PI control can not eliminate steady-state amplitude and phase errors of grid-connected current, and the function of anti-interference isn't good, Simulation study is made with the tool-boxes of SIMULINK in the MATLAB through theoretical analysis and simulation, effectiveness of PCI control is verified.

The basic principles of the fiber-circled cavity ring-down spectroscopy were described. A new gas measurement system based on the fiber-circled cavity ring-down spectroscopy using continuous wave (CW) laser was designed and constructed. And the precise research about the principles and functions of the main devices was made during the designing process. Through analyzing the change of loss before and after filling H2S gas, know that the insertion loss cannot exceed 0.01dB.Because gain fluctuation of erbium doped fiber amplifier(EDFA) seriously influences measurement accuracy, a method which stabilizes the gain of EDFA was introduced, and the change of gain stability characteristics was compared. After adding the feedback loop, the gain changes within 0.01dB, and the measuring precision is 1ppm. The decay characteristics of H 2 S gas with different concentrations and the empty cavity at different loss levels were obtained. From the experiment results, as the gas concentration increased, the decay time declined. Influencing factors on measurement precision were analyzed, and a new method for the high accuracy gas concentration in-situ measurement was proposed.

Snake model is taken into account in order to effectively extract the waterdrops shape of hydrophobic image. Because the fixed energy parameters were used for the whole curve's deformation resulting in over convergence or inconsecutive edges, the Balloon Snake model with adaptive parameters is proposed in this paper. Firstly, the initial contour which is close to the true contour is confirmed based on the principle of region homogeneity. Secondly, according to the prior knowledge of waterdrops shape, each energy parameter can be adjusted during the curve's deformation, respectively, until the curve stops at the true contour. Finally, compared with the original Snake model, experimental results demonstrate that the proposed method has better performance than original Snake for the waterdrops shape extraction of hydrophobic image.