Fuzzy Based Interleaved Step-up Converter for Electric Vehicle

This work focuses on the fuzzy controller for the proposed three-phase interleaved Step-up converter(ISC).The fuzzy controller for the proposed ISC converters for electric vehicles has been discussed in detail.The proposed ISC direct current(DC-DC)converter could also be used in automobiles,satellites,industries,and propulsion.To enhance voltage gain,the proposed ISC Converter combines boost converter and interleaved converter(IC).This design also reduces the number of switches.As a result,ISC converter switching losses are reduced.The proposed ISC Converter topology can produce a 143 V output voltage and 1 kW of power.Due to the high voltage gain of this converter design,it is suitable for medium and high-power systems.The proposed ISC Converter topology is simulated in MATLAB/Simulink.The simulated output displays a high output voltage.But the output voltage contains maximum ripples.Fuzzy proposes an ISC Converter which makes closed loop responsiveness and reduces the output voltage ripple.The proposed ISC converter has the lowest ripple output voltage,which is less than 2%,because the duty cycle is regulated using the fuzzy logic controller.It offers high voltage gain,minimal ripple,and low switching loss.The performance of the proposed converter is compared to that of the fuzzy and Pro-portional Integral(PI)controllers implemented in MATLAB.

一种低输入电压、低功率Step-up DC-DC变换器的设计

文章提出一种Step-up DC-DC的变换器的设计方法,效率高达70%,输入电压范围低至500 mV,最小起动电压能够达到300 mV。

One-step laparoscopic pancreatic necrosectomy verse surgical step-up approach for infected pancreatic necrosis:a case-control study

BACKGROUND:The surgical step-up approach often requires multiple debridements and might not be suitable for infected pancreatic necrosis(IPN)patients with various abscesses or no safe route for percutaneous catheter drainage(PCD).This case-control study aimed to investigate the safety and effectiveness of one-step laparoscopic pancreatic necrosectomy(LPN)in treating IPN.METHODS:This case-control study included IPN patients undergoing one-step LPN or surgical step-up in our center from January 2015 to December 2020.The short-term and long-term complications after surgery,length of hospital stay,and postoperative ICU stays in both groups were analyzed.Univariate and multivariate logistic regression analyses were performed to explore the risk factors of major complications or death.RESULTS:A total of 53 IPN patients underwent one-step LPN and 37 IPN patients underwent surgical step-up approach in this study.There was no significant difference in the incidence of death,major complications,new-onset diabetes,or new-onset pancreatic exocrine insufficiency between the two groups.However,the length of hospital stay in the one-step LPN group was significantly shorter than that in the surgical step-up group.Univariate regression analysis showed that the surgical approach(one-step/step-up)was not the risk factor for major complications or death.Multivariate logistic regression analysis indicated that computed tomography(CT)severity index,American Society of Anesthesiologists(ASA)class IV,and white blood cell(WBC)were the significant risk factors for major complications or death.CONCLUSION:One-step LPN is as safe and effective as the surgical step-up approach for treating IPN patients,and reduces total hospital stay.

Mortality and morbidity in necrotizing pancreatitis managed on principles of step-up approach:7 years experience from a single surgical unit

AIM To determine percentage of patients of necrotizing pancreatitis(NP) requiring intervention and the types of interventions performed. Outcomes of patients of step up necrosectomy to those of direct necrosectomy were compared. Operative mortality, overall mortality, morbidity and overall length of stay were determined. METHODS After institutional ethics committee clearance and waiver of consent, records of patients of pancreatitis were reviewed. After excluding patients as per criteria, epidemiologic and clinical data of patients of NP was noted. Treatment protocol was reviewed. Data of patients in whom stepup approach was used was compared to those in whom it was not used. RESULTS A total of 41 interventions were required in 39% patients. About 60% interventions targeted the pancreatic necrosis while the rest were required to deal with the complications of the necrosis. Image guided percutaneous catheter drainage was done in 9 patients for infected necrosis all of whom required further necrosectomy and in 3 patients with sterile necrosis. Direct retroperitoneal or anterior necrosectomy was performed in 15 patients. The average time to first intervention was 19.6 d in the non step-up group(range 11-36) vs 18.22 d in the Step-up group(range 13-25). The average hospital stay in non step-up group was 33.3 d vs 38 d in step up group. The mortality in the step-up group was 0%(0/9) vs 13%(2/15) in the non step up group. Overall mortality was 10.3% while post-operative mortality was 8.3%. Average hospital stay was 22.25 d.CONCLUSION Early conservative management plays an important role in management of NP. In patients who require intervention, the approach used and the timing of intervention should be based upon the clinical condition and local expertise available. Delaying intervention and use of minimal invasive means when intervention is necessary is desirable. The step-up approach should be used whenever possible. Even when the classical retroperitoneal catheter drainage is not feasible, there should be an attempt to follow principles of step-up technique to buy time. The outcome of patients in the step-up group compared to the non stepup group is comparable in our series. Interventions for bowel diversion, bypass and hemorrhage control should be done at the appropriate times.

Controversies in the treatment of Crohn’s disease: The case for an accelerated step-up treatment approach

The ideal treatment strategy for Crohn’s disease (CD) remains uncertain, as does the optimal endpoint of therapy. Top-down versus step-up describes two different approaches: early use of immunomodulators and biological agents in the former versus initial treatment with steroids in the latter, with escalation to immunomodulators or biological drugs in patients proven to be steroid refractory or steroid dependent. Top-down therapy has been associated with higher rates of mucosal healing. If mucosal healing proves to be associated with better long-term outcomes, such as a decreased need for hospitalization and surgery, top-down therapy may be the better approach for many patients. The main concern with the top-down approach is the toxicity of the immunomodulators and biological agents, which have been linked with infectious complications as well as an increased risk of lymphoma. It is unlikely that one strategy will be best for all patients given the underlying heterogeneity of CD presentation and severity. Ultimately, we must weigh the safety and efficacy of the therapies with the risks of the disease itself. Unfortunately our ability to risk stratify patients at diagnosis remains rudimentary. The purpose of this paper is to review the data that supports or refutes the differing treatment paradigms in CD, and to provide a rationale for an approach, termed the "accelerated step-up" approach, which attempts to balance the risks and benefits of our currently available therapies with the risk of disease related complications as we understand them in 2008.

Step-up approach in emphysematous hepatitis: A case report

BACKGROUND Emphysematous hepatitis(EH)is a rare,rapidly progressive fulminant gasforming infection of the liver parenchyma.It is often fatal and mostly affects diabetes patients.CASE SUMMARY We report a case of EH successfully managed by a step-up approach consisting of aggressive hemodynamic support,intravenous antibiotics,and percutaneous drainage,ultimately followed by laparoscopic deroofing.Of 11 documented cases worldwide,only 1 of the patients survived,treated by urgent laparotomy and surgical debridement.CONCLUSION EH is a life-threatening infection.Its high mortality rate makes timely diagnosis essential,in order to navigate treatment accordingly.

Analysis and Design of Single Switch Hybrid Step-Up Converter

A Single Switch Hybrid Step-up Converter with high voltage gain, which is suitable for renewable energy system, is proposed in this paper. The proposed converter consists of one switched diode-inductor cell and a capacitor. While switching, both are charged in parallel from the input source and discharged in series to the output. In order to obtain extra voltage gain at lower duty cycle, the voltage multiplier cell is integrated with the proposed converter. The main advantages of the converter are high voltage gain, reduced voltage stress, simple structure and low output voltage ripples. The operating principle and steady state theoretical analysis are presented. A 250 W prototype converter is implemented with 12 V input and 120 V output to verify the design and analysis of this converter and it has an efficiency of over 90% in all operations.

Management of acute pancreatitis in Japan: analysis of nationwide epidemiological survey

Acute pancreatitis(AP) is an acute inflammatory disease of the exocrine pancreas. In Japan, nationwide epidemiological surveys have been conducted every 4 to 5 years by the Research Committee of Intractable Pancreatic Diseases, under the support of the Ministry of Health, Labour, and Welfare of Japan. We reviewed the results of the nationwide surveys focusing on the severity assessment and changes in the therapeutic strategy for walled-off necrosis. The severity assessment system currently used in Japan consists of 9 prognostic factors and the imaging grade on contrastenhanced computed tomography. By univariate analysis, all of the 9 prognostic factors were associated with AP-related death. A multivariate analysis identified 4 out of the 9 prognostic factors(base excess or shock, renal failure, systemic inflammatory response syndrome criteria, and age) that were associated with AP-related death. Receiver-operating characteristics curve analysis showed that the area under the curve was 0.82 for these 4 prognostic factors and 0.84 for the 9 prognostic factors, suggesting the comparable utility of these 4 factors in the severity assessment. We also examined the temporal changes in treatment strategy for walled-off necrosis in Japan according to the 2003, 2007, and 2011 surveys. Step-up approaches and lessinvasive endoscopic therapies were uncommon in 2003 and 2007, but became popular in 2011. Mortality has been decreasing in patients who require intervention for walled-off necrosis. In conclusion, the nationwide survey revealed the comparable utility of 4 prognostic factors in the severity assessment and the increased use of less-invasive, step-up approaches with improved clinical outcomes in the management of walled-off necrosis.

Design of small-area and high-efficiency DC-DC converter for 1 T SRAM

The direct current-direct current （DC-DC） converter is designed for 1 T static random access memory （SRAM） used in display driver integrated circuits （ICs）, which consists of positive word-line voltage （VpwL）, negative word-line voltage （VinyL） and half-VDD voltage （VHDo） generator. To generate a process voltage temperature （PVT）-insensitive VpWL and VNWL, a set of circuits were proposed to generate reference voltages using bandgap reference current generators for respective voltage level detectors. Also, a VOWL regulator and a VNWL charge pump were proposed for a small-area and low-power design. The proposed VpwL regulator can provide a large driving current with a small area since it regulates an input voltage （VCI） from 2.5 to 3.3 V. The VmvL charge pump can be implemented as a high-efficiency circuit with a small area and low power since it can transfer pumped charges to VNWL node entirely. The DC-DC converter for 1 T SRAM were designed with 0.11 μm mixed signal process and operated well with satisfactory measurement results.

QFP接地失效研究

SMT技术的发展促进了电子制造业的繁荣，芯片封装技术得到前所未有的发展，作为一种常规的封装形式，通过QFP封装技术（Plastic Quad Flat Pockage）实现的CPU技术蓟装操作方便，寄生参数减小，适合高频应用，基于QFP封装的以上特点，QFP的可制造性及产品的焊接可靠性要求也越来越高，根据业界各大厂商的提供的资料，焊脚的平面和接地焊盘的平面有0．05-0．15mm不等的间距，焊接的难点主要出现在接地不良以及I／O开路，为了提高制造良率，必须详细探讨QFP的结构特点，以便更好地提高整机焊接的可靠性。

SARS-CoV-2 and the pancreas: What do we know about acute pancreatitis in COVID-19 positive patients?

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)can cause pancreatic damage,both directly to the pancreas via angiotensin-converting enzyme 2 receptors(the transmembrane proteins required for SARS-CoV-2 entry,which are highly expressed by pancreatic cells)and indirectly through locoregional vasculitis and thrombosis.Despite that,there is no clear evidence that SARS-CoV-2 is an etiological agent of acute pancreatitis.Acute pancreatitis in coronavirus disease 2019(COVID-19)positive patients often recognizes biliary or alcoholic etiology.The prevalence of acute pancreatitis in COVID-19 positive patients is not exactly known.However,COVID-19 positive patients with acute pancreatitis have a higher mortality and an increased risk of intensive care unit admission and necrosis compared to COVID-19 negative patients.Acute respiratory distress syndrome is the most frequent cause of death in COVID-19 positive patients and concomitant acute pancreatitis.In this article,we reported recent evidence on the correlation between COVID-19 infection and acute pancreatitis.

40/28纳米存储器IP技术综述

本文介绍了28nm/40nm存储器I P的设计挑战及智原科技提供的相应解决方案。硅验证的结果也证明了有效性。这些技术包括:ROM设计裕度改进、SRAM读写辅助方案、在低VCC电压自适跟踪的检测裕度控制方案和在双端口SRAM中同时访问双端口时单元电流增强。所提出的方法都是对工艺参数波动容忍,适合编译器的有效解决方案并减少面积开销。

Real-world insights for the evolving intervention strategy for non-mild acute pancreatitis:35-year experience in a Chinese Tertiary Center

Background:With the accumulation of experience and evidence,guidelines for invasive intervention for acute pancreatitis(AP)have continuously evolved,followed in Peking Union Medical College Hospital(PUMCH).We aimed to review AP case series to help understand the impact of guideline evolution on the management and prognosis of AP in real-world practice.Methods:This was a single-center study of AP patients who had received invasive interventions from 1988 to 2022.Patient demographics,baseline severity,imaging findings,and the indication,timing,and specific modalities of invasive interventions were collected.The composite primary endpoint was death during hospitalization or major complications after intervention.Other endpoints included pancreatic fistula,incision infection,number of interventions,length of intensive care stay,length of hospitalization,and total medical cost.Results:A total of 195 patients were included.The most common indication for invasive intervention was suspected infection,followed by persistent symptoms.The step-up and delayed strategies reduced the incidence of major complications or death.Over 35 years,the number of patients requiring surgery has gradually declined,and more patients need only minimally invasive procedures for remission.The incidence of the primary outcome decreased as well as the duration of hospitalization.Conclusions:The management of AP patients at PUMCH in the last 35 years has undergone therapeutic guideline changes that support the efficacy and safety of the deferred step-up strategy in real-world practice.

Design of a Level-3 electric vehicle charging station using a 1-MW solar system via the distributed maximum power point tracking technique

Solar power is mostly influenced by solar irradiation,weather conditions,solar array mismatches and partial shading conditions.Therefore,before installing solar arrays,it is necessary to simulate and determine the possible power generated.Maximum power point tracking is needed in order to make sure that,at any time,the maximum power will be extracted from the photovoltaic system.However,maximum power point tracking is not a suitable solution for mismatches and partial shading conditions.To overcome the drawbacks of maximum power point tracking due to mismatches and shadows,distributed maximum power point tracking is util-ized in this paper.The solar farm can be distributed in different ways,including one DC-DC converter per group of modules or per module.In this paper,distributed maximum power point tracking per module is implemented,which has the highest efficiency.This technology is applied to electric vehicles(EVs)that can be charged with a Level 3 charging station in<1 hour.However,the problem is that charging an EV in<1 hour puts a lot of stress on the power grid,and there is not always enough peak power reserve in the existing power grid to charge EVs at that rate.Therefore,a Level 3(fast DC)EV charging station using a solar farm by implementing distributed maximum power point tracking is utilized to address this issue.Finally,the simulation result is reported using MATLAB®,LTSPICE and the System Advisor Model.Simulation results show that the proposed 1-MW solar system will provide 5 MWh of power each day,which is enough to fully charge~120 EVs each day.Additionally,the use of the proposed photovoltaic system benefits the environment by removing a huge amount of greenhouse gases and hazardous pollutants.For example,instead of supplying EVs with power from coal-fired power plants,1989 pounds of CO_(2) will be eliminated from the air per hour.

Microbiota transplantation： concept, methodology and strategy for its modernization

Fecal microbiota transplantation （FMT） has become a research focus of biomedicine and clinical medicine in recent years. The clinical response from FMT for different diseases provided evidence for microbiota-host interactions associated with various disorders, including Clostridium difficile infection, inflammatory bowel disease, diabetes mellitus, cancer, liver cirrhosis, gut- brain disease and others. To discuss the experiences of using microbes to treat human diseases from ancient China to current era should be important in moving standardized FMT forward and achieving a better future. Here, we review the changing concept of microbiota transplantation from FMT to selective microbiota transplantation, methodology development of FMT and step- up FMT strategy based on literature and state experts＇ perspectives.

Inguinoscrotal region as an unusual site of extra-pancreatic collections in infected pancreatic necrosis

Severe acute pancreatitis often leads to pancreatic and peripancreatic collections but,rarely,it can lead to collections at sites remote from the pancreas.Three male patients presented with abdominal pain and inguinoscrotal swelling.They were initially misdiagnosed with obstructed inguinal hernia,epididymo-orchitis and hydrocele,respectively.Later,their diagnosis of acute pancreatitis was revealed on laparotomy in one patient and on computed tomography(CT)in the remaining two patients.All these cases had extensive peripancreatic necrosis and paracolic collections tracking along the psoas muscle,downwards towards the pelvis.These collections were initially managed by percutaneous drainage and saline irrigation as a part of the‘step-up’approach.Two of these patients required open necrosectomy,while all required incision and drainage of inguinoscrotal collections.All the patients were discharged in satisfactory condition.Inguinoscrotal swelling is unusual as a first presentation of acute pancreatitis.A high index of suspicion,with careful study of patient’s history and examination along with CT,may provide an accurate diagnosis.Local drainage may be required to control sepsis and also provide an egress route for intra-abdominal collections.

PV Maximum Power-point Tracking Using Modified Particle Swarm Optimization under Partial Shading Conditions

A novel maximum power-point tracking approach is proposed based on studies investigating the output characteristics of photovoltaic(PV)systems under partial shading conditions.The existence of partially shaded conditions leads to the presence of several peaks on PV curves,which decrease the efficiency of conventional techniques.Hence,the proposed algorithm,which is based on the modified particle-swarm optimization(MPSO)technique,increases the output power of PV systems under such abnormal conditions and has a better performance compared to other methods.The proposed method is examined under several scenarios for partial shading condition and non-uniform irradiation levels using Matlab,and to investigate its effectiveness adequately,the results of the proposed method are compared with those of the neural network technique.The experimental results show that the proposed method can decrease the interference of the local maximum power-point to cause the PV system to operate at a global maximum power-point.The efficiency of the MPSO is achieved with the least number of steady-state oscillations under partial shading conditions compared with the neural network method.

Acute necrotizing pancreatitis:challenges and interventions—a narrative review

Acute pancreatitis(AP)is a complicated disease with rising incidence over the years.Twenty percent of AP will develop into acute necrotizing pancreatitis(ANP).Interventions for ANP have evolved from traditional open surgery to minimally invasive step-up approaches.Infected pancreatic necrosis(IPN)is the most serious event of ANP and associated with extremely poor prognosis.The contrast-enhanced computed tomography(CECT)-based classification of IPN describes various types of IPN and will help to carry out surgical interventions for each subtype.Nevertheless,many challenges are still remaining during the treatment of ANP.Including the balance between endoscopic and surgical approaches,and the selection of optimal timing of surgical intervention for infected necrosis.In nowadays treatment scenario of ANP,the necessity for open surgery remains to be debated.Despite of the development of advanced interventional techniques,postoperative residual infection(PRI)remains thorny,and effective prevention and treatment of PRI is of significance.

High-Voltage-Gain DC-DC Converter with Three-Winding Coupled Inductor

A novel DC-DC converter topology that uses a three-winding coupled inductor(TWCI)and a new voltagemultiplication technique is presented for achieving high voltage gain.The proposed converter comprises one boost unit,one passive absorption circuit,and two voltage-multiplier cells.The tertiary winding of the coupled inductor is connected to a capacitor and diode,and this combination acts as a secondary voltage-multiplier cell(SVMC).The SVMC,when combined with two capacitors,the secondary winding of the coupled inductor,a diode,and a switch,forms a primary voltage-multiplier cell,which can achieve a large voltage-conversion ratio that can be adjusted easily.The new voltage-multiplier technique can be used to decrease the number of capacitors and diodes,which improves the transformation efficiency.A prototype circuit with a nominal rating of 300 W is designed to verify the correctness of theoretical analysis.

Acute necrotizing pancreatitis: challenges and interventions-a narrative review

Acute pancreatitis(AP)is a complicated disease with rising incidence over the years.20%of AP will develop into acute necrotizing pancreatitis(ANP).Interventions for ANP have evolved from traditional open surgery to minimally invasive step-up approaches.Infected pancreatic necrosis(IPN)is the most serious event of ANP and associated with extremely poor prognosis.The CT-based classification of IPN describes various types of IPN and will help to carry out surgical interventions for each subtype.Nevertheless,many challenges are still remaining during the treatment of ANP.Including the balance between endoscopic and surgical approaches,and the selection of optimal timing of surgical intervention for infected necrosis.In nowadays treatment scenario of ANP,the necessity for open surgery remains to be debated.Despite of the development of advanced interventional techniques,postoperative residual infection(PRI)remains thorny,and effective prevention and treatment of PRI is of significance.