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This paper presents the power quality assessment of large synchronous motor starting and loading in the integrated steel-making cogeneration facility. To execute the transient stability analysis, the proper mathematical models, and the accurate parameters of the cogeneration units, excitation systems, governor systems, load, and static var compensators (SVCs) are investigated in detail. Four case studies with or without considering the connection of the power grid, the installation of autotransformer (AT) starter, and SVC are performed to demonstrate the dynamic responses of system frequency, voltage, and cogeneration units due to motor starting and loading. Also, the voltage sag ride-through curve of sensitivity load has been included, and a power quality index (PQI) due to voltage variation in the assessment period has been proposed to find the impact of motor starting and loading on the power quality of the cogeneration system. It is concluded that the system dynamic responses and PQI values have better performance if the AT starter is applied with either the regulation of the SVC system or connection to the bulk power grid. Index Terms--Cogeneration, motor starting, power quality.

This paper presents the influence of the large motor starting and the large rolling mill operation on the isolated integrated steel cogeneration facility by executing the transient stability analysis. The system configuration of the steel facility will be introduced first. Furthermore, the proper mathematical models and the accurate parameters of the cogeneration units, excitation systems, and governor systems are investigated in detail. Both the static and dynamic load models are applied in this paper. To reduce the starting current of large motors, the conventional step-down voltage method by adjusting the suitable tap position of the autotransformer and the constant magnetic flux control method by using the variable-voltage and variable-frequency inverter are considered in the computer simulations. Also, the system voltage and frequency fluctuations due to the operation of the rolling mill will he observed and investigated carefully to verify that the isolated cogeneration can be operated well and safely. Index Terms--Cogeneration, motor starting, transient stability.

This paper presents the proper design of protective relay settings for tie-line tripping and load shedding of a cogeneration system in a high-tech science-based industrial park in Taiwan, R.O.C. To improve the power service quality for the industrial customers, two 161/161-kV transformers with tap changers have been designed to be in series with the tie line. According to the transient stability analysis, the voltage levels at the customer buses can be significantly improved during the time interval of utility fault. The reduction of the voltage drop at the cogeneration bus can also benefit the critical clearing time to restore the stable operation of the cogeneration units after system disturbance. To comply with the fault interruption capacity of the circuit breakers of other industrial customers served by the same utility substation, the series transformers can effectively reduce the fault current magnitude supplied by the cogeneration units. It is found that the application of the series transformers and the cogeneration system with proper protective relay settings can enhance the power service quality of high-tech industrial customers by providing better voltage control and transient stability. Index Terms--Cogeneration, relay design, Science-Based Industrial Park.

Background and Aims: Regorafenib has demonstrated its survival benefit for unresectable hepatocellular carcinoma (uHCC) patients in a phase III clinical trial. We aimed to assess the efficacy and tolerability of regorafenib and the predictors of treatment outcomes in Taiwanese patients. Methods: We analyzed the survival, best overall response, predictors of treatment outcomes, and safety for uHCC patients who had tumor progression on sorafenib therapy and received regorafenib as salvage therapy between March 2018 and November 2020. Results: Eighty‐six patients with uHCC were enrolled (median age, 66.5 years; 76.7% male). The median regorafenib treatment duration was 4.0 months (95% confidence interval [CI], 3.6–4.6). The most frequently reported adverse events were hand‐foot skin reaction (44.2%), diarrhea (36.0%), and fatigue (29.1%). No unpredictable toxicity was observed during treatment. The median overall survival (OS) with regorafenib was 12.4 months (95% CI, 7.8–17.0) and the median progression‐free survival (PFS) was 4.2 months (95% CI, 3.7–4.7). Of 82 patients with regorafenib responses assessable, 4 patients (4.9%) achieved a partial response, and 33 (40.2%) had stable disease, leading to a disease control rate (DCR) of 45.1% (n = 37). Patients possessing baseline AFP < 400 ng/ml exhibited a markedly longer median OS, median PFS, and higher DCR compared with their counterparts (15.7 vs. 8.1 months, 4.6 vs. 3.7 months, 60.9% vs. 27.5%, respectively). Despite possessing high baseline AFP levels, patients with early AFP response (>10% reduction at 4 weeks or >20% reduction at 8 weeks after regorafenib administration) exhibited comparable treatment outcomes to those with baseline AFP < 400 ng/ml. Conclusions: The results of this real‐world study verified the tolerability and efficacy of regorafenib treatment for uHCC patients who failed prior sorafenib therapy, especially for those with lower baseline AFP levels or with early AFP response. [ABSTRACT FROM AUTHOR]

This paper has developed the coordination of load shedding scheme and superconducting magnetic energy storage (SMES) unit to enhance the transient stability of a large industry cogeneration facility. The load-shedding scheme and the tie line tripping strategy by using the frequency relays have been designed to prevent the power system from collapse when an external fault of utility power system occurs. An actual external fault case and a simulated internal fault case have been selected to verify the accuracy of load shedding scheme by executing the transient stability analysis. To improve the frequency and voltage responses, an SMES unit with various control modes has been installed in the cogeneration system. The sensitivity analysis of SMES unit with different parameters is applied to achieve better system responses. Besides, an SMES unit with active power deviation as feedback signal is also considered to improve the electric power fluctuation of the study plant with rolling mills. It is found that the SMES system will enhance the electric power quality and minimize the economic losses of the cogeneration facility due to unnecessary load shedding. Index Terms--Cogeneration, superconducting magnetic energy storage, transient stability.

Background and Aim: Hepatitis B virus (HBV) surface antigen (HBsAg) seroreversion usually occurs during immunosuppressive therapy. The risk and factors of HBsAg seroreversion from resolved HBV infection in the general population remained unclear. Methods: This retrospective study enrolled subjects with resolved HBV infection and who had received at least two times of screening in a longitudinal community screening program. HBsAg, hepatitis B surface antibody (anti‐HBs), and hepatitis C virus antibody (anti‐HCV) were tested every time in all subjects. The primary endpoint was HBsAg seroreversion. Results: Of the 7630 subjects enrolled, 5158 (67.6%) subjects had positive anti‐HBs at baseline. HBsAg seroreversion occurred in 84 subjects during 42 815‐person‐year follow‐up with an annual incidence of 0.2% and a 10‐year cumulative risk of 1.9%. Anti‐HBV treatment‐experienced subjects had a significantly higher risk of HBsAg seroreversion than anti‐HBV treatment‐naive subjects (83/310 [26.8%] vs 1/7320 [0.01%], P < 0.001). Lower rates of positive anti‐HBs and anti‐HCV were observed in anti‐HBV treatment‐experienced subjects who developed HBsAg seroreversion. Both positive anti‐HBs (hazard ratio/95% confidence interval: 0.56/0.348–0.903, P = 0.017) and positive anti‐HCV (hazard ratio/95% confidence interval: 0.08/0.030–0.234, P < 0.001) were independent factors of HBsAg seroreversion in anti‐HBV treatment‐experienced subjects. Less than 5% of the HBsAg seroreverters had clinical hepatitis flare at HBsAg seroreversion. The HBsAg titer was low, and only transient reappeared in most of the HBsAg seroreverters. Conclusions: Subjects with resolved HBV infection were at a minimal risk of HBsAg seroreversion, unless with prior anti‐HBV treatment experience. Fortunately, even with a reappearance of HBsAg, it was transient and clinically non‐relevant. [ABSTRACT FROM AUTHOR]

Background and Aim: Hemodialysis patients are at increased risk of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. Both HBV and HCV infections lead to risks of end‐stage liver diseases and extrahepatic manifestations. This study aimed to investigate hepatic and extrahepatic comorbidities in hemodialysis patients with HBV or HCV infections compared with those without viral hepatitis. Methods: A total of 1910 hemodialysis patients, including 159 HCV viremic patients (HCV group), 217 seropositive for HBV surface antigen (HBsAg, HBV group) and 1534 seronegative for both anti‐HCV and HBsAg (non‐B and non‐C [NBNC] group), from 23 hemodialysis centers were enrolled. Comorbidities were classified into 10 categories by the International Classification of Diseases‐10th Revision. Results: Among the 1910 patients, the mean age was 64.6 years, and 52.7% were male patients. A total of 1834 (96%) patients had at least one comorbidity, and the mean number of comorbidities was 2.9 ± 1.5 per person. The three most common comorbidities were hypertension, diabetes, and ischemic heart diseases. The mean number of comorbidities per person was significantly higher in the HCV group (3.3 ± 1.7) than in the HBV (2.7 ± 1.5, P < 0.001) and NBNC groups (2.9 ± 1.5, P = 0.004), mainly due to the higher prevalence of ischemic heart disease, respiratory disorders, and mental/behavioral disorders. The HBV and NBNC groups exhibited comparable burdens of comorbidities. Conclusions: Hemodialysis patients had a high prevalence of multiple comorbidities. Hemodialysis patients with HCV exhibited a higher burden of comorbidities, especially ischemic heart diseases, respiratory disorders, and mental/behavioral disorders, than HBV and NBNC patients did. [ABSTRACT FROM AUTHOR]

Uraemic patients undergoing haemodialysis are at high risk of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. We aimed to evaluate the evolutionary seroprevalence of viral hepatitis and the gap in HCV care cascades in this special population by a large‐scale surveillance study in Taiwan. Uraemic patients on maintenance haemodialysis from 22 sites (FORMOSA‐LIKE group) in 2012 (n = 1,680) and 2019 (n = 2,326) were recruited for this study. The distributions and sequential changes of viral hepatitis markers were analysed. The prevalence of anti‐HCV antibody and hepatitis B surface antigen (HBsAg) seropositivity was 13.6% (316/2326) and 11.5% (267/2326), respectively, in 2019 compared with 17.3% (290/1680, P =.002) and 13.6% (229/1680, P =.046), respectively, in 2012. The HCV‐viremic rate among anti‐HCV‐seropositive patients was significantly lower in 2019 than in 2012 (56.3% [178/316] vs. 73.8% [214/290], P <.001). The HCV treatment rate increased from 2.3% (5/217) in 2012 to 21.7% (49/226) in 2019 (P <.001). In the sequential analysis of the 490 patients who participated in both screens, 17 of the 55 HCV‐viremic patients became HCV RNA seronegative, including 13 by antivirals and four spontaneously. By contrast, one anti‐HCV‐seropositive but nonviremic patient became viremic, and six anti‐HCV‐seronegative patients became anti‐HCV‐seropositive in 2019. The annual incidence of new HCV was 0.2%/year. Seven HBsAg‐seropositive patients experienced HBsAg loss (1.25%/year). Two patients had new anti‐HBc seropositivity (new HBV exposure: 0.57%/year). The seroprevalence of viral hepatitis decreased in an 8‐year follow‐up but remained prevalent, and the treatment of HCV infection was underutilized in uraemic patients. Additional efforts are needed to enhance the HCV treatment uptake of uraemic patients. Clinical Trial IDs: NCT03803410, NCT01766895. [ABSTRACT FROM AUTHOR]

This article proposes a fault identification method that is embedded in an asset management system (AMS) to identify the faulted location based on the fault flags reported from the fault indicators (FIs). The fault identification model based on the Petri-net technology is developed using the distribution network topology generated by a geographic information system. The proposed method uses the data set of fault flags generated by FIs, the statuses of circuit breakers, the available precurrent and postcurrent measurements of FIs, and the loadings of distribution feeders and laterals. The hybrid communication system is applied to provide two-way communication between the control center and FIs. The AMS with the embedded fault identification method can dispatch the repair crews to the fault location faster to accelerate the customer service restoration. A distribution feeder of Taiwan Power Company was selected for the computer simulation to demonstrate the effectiveness of the proposed method by using the communication-capable FIs to identify the exact fault location of distribution lines after a short circuit fault occurs in a distribution system. [ABSTRACT FROM AUTHOR]

Background/Aims: Undetectable HCV RNA 12 weeks after the end of treatment (SVR12) has been the valid efficacy endpoint in the era of direct-acting antivirals (DAAs). Its concordance with SVR4 and SVR24 and long-term durability is unknown in Taiwanese chronic hepatitis C (CHC) patients. Methods: A total of 1080 CHC patients who received all-oral DAAs and an achieved end-of-treatment virological response (EOTVR), defined as undetectable HCV RNA at the end of therapy, were consecutively enrolled. HCV RNA was monitored 4, 12, and 24 weeks after EOT. Patients who achieved SVR24, defined as undetectable HCV RNA 24 weeks after EOT, were followed annually for assessing SVR durability. Results: Eleven (1.02%) patients experienced HCV RNA reappearance after EOT. The most frequent timing of RNA reappearance was observed at SVR4 (n = 7), followed by SVR12 (n = 3) and SVR 24 (n = 1). The positive predictive value (PPV) and negative predictive value (NPV) of SVR4 in predicting SVR12 were 99.7% and 100%, respectively, whereas the PPV and NPV of SVR12 in predicting SVR24 were 99.9% and 100%, respectively. Pyrosequencing confirmed delayed relapse rather than reinfection for the patient who had detectable HCV RNA at SVR24. Among 978 patients who achieved SVR24, after a median follow-up period of 17.3±8.2 months, the SVR durability is 100% up to a 4-year follow-up. Conclusion: Achievement of SVR12 provides excellent durability of HCV seroclearance after DAA therapy. On-demand HCV RNA beyond SVR12 should be recommended for patients with unexplainable abnormal liver function or high-risk behaviors. [ABSTRACT FROM AUTHOR]

Background: The biochemical response is a crucial indicator of prognosis in chronic hepatitis B (CHB) patients treated with nucleotide/nucleoside analogues (NAs). The impact of hepatitis D virus (HDV) infection on alanine aminotransferase normalization is elusive.Methods: The longitudinal study recruited 1185 CHB patients who received NAs. These patients were tested for anti-HDV antibody and HDV RNA at the initiation of anti-hepatitis B virus (HBV) therapy and annually for patients who were HDV-seropositive. ALT levels were examined at the first and second year of anti-HBV therapy. ALT abnormality was defined as ALT levels above 40 IU/mL in both male and female, and the risk factors associated with ALT abnormality were analysed.Results: Rates of seropositivity for anti-HDV and HDV RNA were 2.0% and 0.8% among 1185 NA-treated CHB patients, respectively. The strongest factor associated with ALT abnormality (>40 IU/mL) after first year treatment with NAs was HDV RNA seropositivity at year 1 (odds ratio [OR]/95% confidence interval [CI]: 31.44/3.49-283.56, P = 0.002), followed by liver cirrhosis (2.18/1.51-3.15, P < 0.001), detectable HBV DNA at year 1 (OR/CI: 1.99/1.36-2.92, P < 0.001), diabetes (OR/CI: 1.75/1.10-2.78, P = 0.02), body mass index (BMI) (OR/CI: 1.13/1.09-1.18, P < 0.001) and age (OR/CI: 0.97/0.96-0.98, P < 0.001). Among patients who were seronegative for HBV DNA at year 1, the strongest factor associated with ALT abnormality was HDV RNA seropositivity at year 1 (OR/CI: 30.00/3.28-274.05, P = 0.003), followed by liver cirrhosis (OR/CI: 1.83/1.21-2.75, P = 0.004), BMI (OR/CI: 1.16/1.11-1.21, P < 0.001) and age (OR/CI: 0.97/0.96-0.99, P < 0.001). Similarly, the impact of HDV RNA seropositivity on ALT abnormality was noted in patients without detectable HBV DNA but not in those with hepatitis B viremia at treatment year 2 (OR/CI: 10.16/1.33-77.74, P = 0.03).Conclusion: HDV infection played an important role in ALT abnormality in CHB patients receiving 1-year and 2-year NAs. The impact was particularly noted in patients who had successfully suppressed HBV DNA. [ABSTRACT FROM AUTHOR]

This article presents the innovative control scheme of renewable ancillary services to support the system operation of a bulk power system with high penetration of renewable energy. The smart inverters of PV systems can be controlled to adjust the renewable generation of real and reactive power according to the variation of system voltage and frequency. The dispatch control of renewable ancillary services is integrated with the energy management system to achieve the coordination control of renewable energy and synchronous generators. The sensitivity factors of renewable system was applied to determine the generation curtailment for the mitigation of line overloading. The ancillary service of reactive power compensation by renewable energy was considered to improve the system voltage quality. The emergency generation control of renewable systems with fast ramping up capability was applied to illustrate the effectiveness of renewable ancillary service to improve the system frequency response after sudden generator tripping. Based on the computer simulation of an actual power system with large renewable energy to be integrated, the functions of virtual synchronous generators by the photovoltaic systems and wind farms have to be applied to ensure the successful steady-state operation and to improve the system transient stability for severe disturbance contingency. [ABSTRACT FROM AUTHOR]

Background and Aim: The serial serologic changes of hepatitis D virus (HDV) infection among chronic hepatitis B virus (HBV) infected patients who received oral nucleotide/nucleoside analogues are elusive. Methods: Serum anti‐HDV and HDV RNA among chronic hepatitis B (CHB) patients were tested at the time of initiating anti‐HBV therapy and subsequently during the follow‐up period. Results: The seropositive rate of anti‐HDV and HDV RNA among 2850 CHB patients, was 2.7% and 0.9%, respectively. Factors associated with anti‐HDV seropositivity were platelet counts (odds ratio [OR]/95% confidence intervals [CI]: 0.995/0.992–0.999; P = 0.006), HBV DNA levels (OR/CI: 0.81/0.70–0.94; P = 0.005), and hepatitis B e‐antigen (HBeAg) seropositivity (OR/CI: 0.22/0.05–0.95; P = 0.04). The only factor associated with HDV RNA positivity among anti‐HDV seropositive patients was age (OR/CI: 0.95/0.90–1.00; P = 0.03). The spontaneous clearance rate of serum anti‐HDV antibody was 3.0 per 100 person‐years with a median follow‐up period of 3.5 years (range 2–12 years), whereas the seroclearance rate of HDV RNA was 4.3 per 100 person‐years among anti‐HDV seropositive patients after a median follow‐up period of 6.0 years (range 2–11 years). A baseline anti‐HDV titer < 0.5 cut‐off index was the only factor predictive of anti‐HDV seroclearance (hazard ratio [HR]/CI: 30.11/3.73–242.85; P = 0.001). Conclusions: HDV infection was not common among patients treated for HBV in Taiwan. Seroclearance of anti‐HDV and HDV RNA did occur over time, albeit the chance is rare. [ABSTRACT FROM AUTHOR]

Background and Aims: The features of non-viral, nonalcohol hepatocellular carcinoma (NBNC-HCC) remain elusive. The aim of this study was to investigate this clinical characteristics and overall survival of NBNC-HCC compared to hepatitis B- (HBV-HCC) and hepatitis C-related (HCV-HCC) HCC.Methods: We analyzed the etiologies, fibrosis stages, clinical data, and outcomes of newly diagnosed patients with HCC.Results: A total of 1777 HCC patients were recruited, including 332 patients with NBNC-HCC, 682 patients with HBV-HCC, 680 patients with HCV-HCC, and 83 patients with HBV/HCV HCC. Patients with NBNC-HCC were older (69.9 ± 11.9 years). Patients with NBNC-HCC exhibited a higher prevalence of diabetes (43.9%) compared to the HBV-HCC (27.1%, p < 0.05) and HCV-HCC (30.2%, p < 0.05) groups. Compared to patients from the viral-related HCC groups, patients with NBNC-HCC exhibited a significantly lower fibrosis stage. NBNC-HCC patients exhibited a higher proportion of Barcelona Clinic Liver Cancer (BCLC) classification stage C and stage D compared to patients from the HBV-HCC and HCV-HCC groups. With a mean of 2.33 ± 2.31 years of follow-up, the median survival of patients with NBNC-HCC was 1.75 (95% CI 1.33-2.17) years, which was significantly lower than that of patients with HBV-HCC (p = 0.041) and HCV-HCC (p < 0.001).Conclusions: Patients with NBNC-HCC have a higher risk of diabetes than patients with HCC of viral etiologies. Although patients with NBNC-HCC exhibited a milder fibrosis stage, their more advanced HCC stages and worse overall survival should be taken into consideration in clinical care. [ABSTRACT FROM AUTHOR]

To enhance the outage quality of a distribution system with a high penetration of photovoltaic (PV) renewable energy, this paper proposes a coordinating control strategy for an on-load tap changer (OLTC) of the main transformer in a distribution substation and PV smart inverters. The voltages at the end points of all distribution feeders that are served by the main transformer and the power generation of each PV system are collected using a SCADA system. The hourly tap position of the OLTC is then derived from the daily profiles of feeder voltage and the injected power that is generated by all PV systems along the feeder. Thereafter, the PV smart inverters perform autonomous control of reactive power compensation so that the voltage at the point of common coupling can be fixed at the specified voltage level. To demonstrate the effectiveness of the proposed voltage-control strategy, a main transformer, which serves six feeders of the Taiwan Power Company(Taipower) with high PV penetration, was considered in a case study. The proposed coordinating control of the OLTC and PV smart inverters dramatically improved the voltage quality of the distribution feeder and enabled the effective mitigation of the impact of large PV integration in the distribution system. [ABSTRACT FROM AUTHOR]

This paper proposes an innovative transformer management system (TMS) for energy control of customer loads and photovoltaic (PV) systems to solve the problems of transformer overloading and overvoltage due to power injection by PV renewable energy. The operation status of distribution transformers is monitored by transformer terminal unit (TTU) and reported to the control master station via the hybrid communication system. The demand response of customer load control is activated to reduce the loading level of transformers for mitigation of overloading problem. For the residential customers with installation of roof top PV system, the TTU is applied to perform the power factor control of smart inverter to prevent the overvoltage problem. The hybrid communication system consisting of power line carrier, LoRa radio frequency, and optical fiber is used to provide two-way communication for data collection and controls of customer loads and PV system. According to the field testing of the proposed TMS in Taiwan Power Company, the adaptive energy control of customer loads by TTU is executed when the overloading problem of distribution transformer occurs. The TTU also performs the power factor control of PV smart inverters to solve the overvoltage problem due to too much of PV power being injected during the solar peak period. The overvoltage problem due to PV power injection has also been solved by TTU for control of PV smart inverters to perform the proper reactive power compensation. [ABSTRACT FROM AUTHOR]

This paper presents the proper underfrequency relay settings to enhance the operation of industrial power systems with cogeneration facilities. A cogeneration unit was installed in the plant in 1996 to supply the power demand of the plant. The cogeneration unit always faces the shutdown problem when a severe fault occurs on the nearby Taipower network. It is, therefore, necessary to investigate the plant protective relay settings to prevent a whole plant blackout when the contingency occurs. The transient stability analysis has been performed by considering both the detailed models of the cogenerators with the governor and exciter control systems and the external utility power system. The underfrequency relay settings for tie line tripping and load shedding are designed to prevent the tripping of the cogeneration units so that the electricity service to the critical loads of the industrial customer can be maintained in case serious external disturbances such as short circuit faults occur. In this study, the scheme of underfrequency relay settings has been developed for the power system of a large synthetic rubber manufacturer with a large cogeneration unit. Three study cases have been selected for the transient stability analysis to verify the effectiveness of the proposed protective relay setting. Index Terms--Load-shedding scheme, transient stability.

This paper presents the effectiveness of the particle swarm optimization (PSO) to minimize the total active power loss of an island scale micro grid distribution network. In the adopted method, the co-simulation of the PSO algorithm and the Mat-power software on an island scale electrical network was proposed. The power system in Kiribati is selected as the study case. Two diesel power generation stations, one voltage regulator unit and one switching shunt capacitor bank are used to regulate the system voltage. The 24-h load flow is executed with the proposed PSO algorithm to minimize the active power loss and the annual power loss savings can be estimated. It is concluded that the proposed PSO algorithm can work well and give a satisfactory result. [ABSTRACT FROM AUTHOR]

This study develops a renewable energy management system (REMS) for the control of photovoltaic (PV) smart inverters to mitigate the voltage violation of distribution systems with high penetration of PV installation. The impact analysis of distribution feeders with the PV system integration for decision making of smart inverter control has been embedded in REMS to solve the voltage violation problem. To verify the effectiveness of the proposed REMS to enhance the system voltage quality, a PV system installed in a distribution feeder of Taiwan Power Company (Taipower) has been selected for field testing. The real power, reactive power, and voltage of the studied PV system have been collected. The impact analysis of PV integration is performed to solve the mitigation of voltage variation by the control of reactive power compensation of smart inverters. It is found that the voltage at the test PV system is very consistent with the field test results. The computer simulation of a distribution feeder with a large PV farm has been executed to illustrate that the control of smart inverters can enhance the utilization of solar energy by reducing the curtailment of renewable power generation dramatically for a distribution system with high penetration of PV systems. [ABSTRACT FROM PUBLISHER]

An intelligent load-shedding strategy was designed and embedded in the special protection system (SPS) to enhance the system stability for an offshore island with high penetration of photovoltaic (PV) systems. To prepare the training dataset for the artificial neural network (ANN), the transient stability analysis of the isolated power system was executed to determine the minimum amount of load to be interrupted to prevent the tripping of diesel generators for the emergency shutdown of PV systems. By selecting various combinations of PV penetration levels, total system load demand, and the frequency decay rate at the instant of PV system tripping as the input neurons of the ANN, the proper load-shedding scheme is derived and stored in the decision knowledge base of the SPS. When the intelligent energy management system detects the tripping of a PV system, the SPS will be triggered to determine the amount of loss to be disconnected and executes the corresponding load interruption. By applying the proposed ANN-based load-shedding scheme in SPS, the amount of customer loading to be interrupted has been reduced dramatically for the restoration of system stability after the emergency shutdown of high-penetration PV system. [ABSTRACT FROM PUBLISHER]

This paper investigates the impacts of a large wind power generation system (WPGS) on the distribution system. The installation of various types of distributed generators (DGs) on the distribution system will significantly affect the operating, planning and maintaining strategies of the utility. In this paper, one practical distribution system of Taiwan Power Company (Taipower) is selected for study. Various power quality issues like steady state voltage variation ratio, reverse power, flicker, short-circuit current as well as harmonic are investigated and calculated by applying the computer program simulation and the simplified calculation methods suggested by the International Electrotechnical Commission (IEC). The results will be compared with the Taipower relative standards to demonstrate the feasibility of the WPGS to be installed in the distribution feeder. [ABSTRACT FROM AUTHOR]

This paper presents the dispatch of reactive power compensation and real power curtailment of photovoltaic (PV) systems to prevent the overvoltage violation when load transfer between distribution feeders is executed. The voltage sensitivity factors of reactive power injection at all PV buses are derived according to the configuration of the distribution network. The advanced distribution automation system issues the control command to each PV inverter for adjustment of PV power generation, according to the sensitivity coefficients and PV installation capacity, so that the ancillary service of voltage support can be provided by all PV systems in a fairer manner. The practical Taiwan Power Company (Taipower) distribution feeders are selected for computer simulation, to verify the effectiveness of the proposed control method to mitigate the voltage violation problem for the operation of load transfer between distribution feeders with high penetration of PV installation. [ABSTRACT FROM AUTHOR]

This paper presents a method for an adaptive relay setting for distribution systems with wind generators (WGs). The advanced distribution automation system (ADAS) is applied to monitor the operational status of WGs and line switches. For the change of operational status of WGs or network reconfiguration of distribution systems because of the operation of line switches, the function of the adaptive relay setting is activated by the ADAS control master station. Short-circuit analysis is performed to solve the magnitude and direction of fault-current flows. The protective relay settings are then accordingly revised and loaded to the protective relays along the feeder to achieve the adaptive fault protection. Sample distribution feeders with open- and closed-loop configurations are used to demonstrate the adaptive relay setting for distribution systems with various operational scenarios of WGs. It is concluded that the fault currents contributed by WGs must be included in the design of the tap/level settings of protective relays by the ADAS to achieve good protection of smart distribution systems. [ABSTRACT FROM PUBLISHER]

The PV penetration level of a distribution system is often limited by the violation of voltage variation caused by large intermittent power generation. This study investigates the use of a distribution static compensator (DSTATCOM) in reactive power compensation for system voltage control, during peak solar irradiation, in order to increase the PV installation capacity of a distribution feeder and avoid the voltage violation problem. PV power generation is simulated using hourly solar irradiation and temperature data provided by the weather bureau. The voltage variation at the point of common coupling (PCC) is also derived by executing the 3-\varphi load flow analysis to determine the maximum PV power injection without causing voltage violation. By applying the proposed voltage control scheme of DSTATCOM during high solar irradiation periods, the total power generation and the total energy delivered by the PV system over one year are determined according to the annual duration of solar irradiation. The annual sales of PV power, the system O&M cost, the cost of DSTATCOM installation and the initial capital investment for a PV system are then used to calculate the cash flow over the system life-cycle and the final net present value (NPV) of the PV project. With the proposed DSTATCOM voltage control to perform reactive power compensation, the optimal installation capacity of PV systems can be determined by maximizing the net present value of the system to ensure the best cost-effectiveness of the PV project and to better utilize solar energy. [ABSTRACT FROM PUBLISHER]

This paper presents the three-phase voltage and unbalance analysis for the distribution systemwith the loading of a light rail transit (LRT) tram. To investigate the dynamic responses of the system voltage and current, this paper adopts the Alternative Transients Program(ATP) software tomodel and simulate amultigrounded four-wire distribution system with an LRT loading. Two different definitions about unbalance are used to evaluate the problem. In this paper, the traction supply substation (TSS) with a singlephase transformer configuration is designed first for providing the electric power to the trams of LRT. However, itmay result in the significant neutral line current and unbalance phenomenon to deteriorate the power quality of the distribution system. A Le-Blanc connection transformer in the TSS is therefore proposed to solve the problems. [ABSTRACT FROM AUTHOR]

Abstract: This article proposes a concept of “effective Seebeck coefficient”, which discusses the inconsistency between the theoretical Seebeck coefficient and the measured one. The inconsistency can be explained via contact effect and thermal resistor network. Two different clamping forces are applied to the TEG module to observe the contact effect. Throughout the experiments, the electric resistance seems insensitive to the clamping force; somehow the thermal contact effect dominates the TEG module performance. In addition, a thermal resistor network, which is used to calculate the exact temperature difference traverse the TE ingot, has been constructed. After applying a suitable clamping pressure and modifying the actual ΔT with thermal resistor network, the “effective Seebeck coefficient” has been proposed. Notably, this proposed value is very helpful for better understanding characteristics of the behavior of the TEG module operating in the actual conditions we provided, and it can be used to predict the performance of the TEG module under any other condition. [Copyright &y& Elsevier]

This paper presents the electric power system analysis and design of an expanding steel cogeneration plant. The site and capacity of shunt capacitor banks as well as the tap position of transformers are determined according to the power flow analysis. Also, to comply with the restriction of circuit breaker capacity, the high-impedance transformers are designed. In addition, the voltage fluctuation resulted from the dramatic reactive power variation of hot strip rolling mill can be greatly reduced if proper static var compensator is installed. The significant voltage sag due to the starting of induction motor can be effectively improved by applying wye–delta transformer starter. Furthermore, the total voltage harmonic distortion and the total current demand distortion are both acceptable if the proper filters are installed. It is also found that the cogeneration system can keep stable operation in autonomous mode by applying the governor control action and the load-shedding scheme after tie line tripping. It is concluded that the power system analyses are important for the steel plant with cogeneration unit to identify hidden problems and remedy strategy to ensure the system power quality and operation performance. [ABSTRACT FROM AUTHOR]

To promote the photovoltaic (PV) installation, a large-scale PV system installed in the Main Stadium of the 2009 World Games has been investigated for the design of selling price of PV power generation. The PV power generation is simulated according to the hourly solar irradiation and temperature provided by the weather bureau. The cash flow of annual power generation, the O&M cost, and the capital investment cost of the PV system is then used to derive the payback years and the internal rate of return for the PV system under different selling price of PV power generation. The voltage variation and the power system loss of the distribution feeder, which serves the Main Stadium, are also performed by executing the 3-\varphi load flow analysis for the impact analysis of the PV system. The results indicate that the reduction of voltage drop and power system loss can be obtained with the PV system installed to provide the dispersed generation for the local loads. However, the PV system penetration is limited due to the violation of voltage variation introduced by the large intermittent PV power generation. The selling price of PV generation has to be designed according to the conditions of solar irradiation and temperature so that sufficient incentives can be provided to encourage more customers to participate the PV program. [ABSTRACT FROM AUTHOR]

Abstract: In this case study, a system to recover waste heat comprised 24 thermoelectric generators (TEG) to convert heat from the exhaust pipe of an automobile to electrical energy has been constructed. Simulations and experiments for the thermoelectric module in this system are undertaken to assess the feasibility of these applications. A slopping block is designed on the basis of simulation results to uniform the interior thermal field that improves the performance of TEG modules. Besides simulations, the system is designed and assembled. Measurements followed the connection of the system to the middle of an exhaust pipe. Open circuit voltage and maximum power output of the system are characterized as a function of temperature difference. Through these simulations and experiments, the power generated with a commercial TEG module is presented. Overview this case study and our previous work, the results establish the fundamental development of low-temperature waste heat thermoelectric generator system that enhances the TEG efficiency for vehicles. [Copyright &y& Elsevier]

Background: Prisoners are at risk of hepatitis C virus (HCV) infection, especially among the people who inject drugs (PWID). We implemented an outreach strategy in combination with universal mass screening and immediate onsite treatment with a simplified pan-genotypic direct-acting antivirals (DAA) regimen, 12 wk of sofosbuvir/velpatasvir, in a PWID-dominant prison in Taiwan., Aim: To implement an outreach strategy in combination with universal mass screening and immediate onsite treatment with a simplified pan-genotypic DAA regimen in a PWID-dominant prison in Taiwan., Methods: HCV-viremic patients were recruited for onsite treatment program for HCV micro-elimination with a pangenotypic DAA regimen, 12 wk of sofosbuvir/ velpatasvir, from two cohorts in Penghu Prison, either identified by mass screen or in outpatient clinics, in September 2019. Another group of HCV-viremic patients identified sporadically in outpatient clinics before mass screening were enrolled as a control group. The primary endpoint was sustained virological response (SVR12, defined as undetectable HCV ribonucleic acid (RNA) 12 wk after end-of-treatment)., Results: A total of 212 HCV-viremic subjects were recruited for HCV micro-elimination campaign; 91 patients treated with sofosbuvir/Ledipasvir or glecaprevir/ pibrentasvir before mass screening were enrolled as a control. The HCV micro-elimination group had significantly lower proportion of diabetes, hypertension, hyperlipidemia, advanced fibrosis and chronic kidney diseases, but higher levels of HCV RNA. The SVR12 rate was comparable between the HCV micro-elimination and control groups, 95.8% (203/212) vs 94.5% (86/91), respectively, in intent-to-treat analysis, and 100% (203/203) vs 98.9% (86/87), respectively, in per-protocol analysis. There was no virological failure, treatment discontinuation, and serious adverse event among sofosbuvir/velpatasvir-treated patients in the HCV micro-elimination group., Conclusion: Outreach mass screening followed by immediate onsite treatment with a simplified pangenotypic DAA regimen, sofosbuvir/velpatasvir, provides successful strategies toward HCV micro-elimination among prisoners., Competing Interests: Conflict-of-interest statement: No author had reported a potential conflict of interest relevant to this work., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: Chronic hepatitis C virus (HCV) infection induces profound alterations in the cytokine and chemokine signatures in peripheral blood. Clearance of HCV by antivirals results in host immune modification, which may interfere with immune-mediated cancer surveillance. Identifying HCV patients who remain at risk of hepatocellular carcinoma (HCC) following HCV eradication remains an unmet need. We hypothesized that antiviral therapy-induced immune reconstruction may be relevant to HCC development., Aim: To investigate the impact of differential dynamics of cytokine expression on the development of HCC following successful antiviral therapy., Methods: One hundred treatment-naïve HCV patients with advanced fibrosis (F3/4) treated with direct-acting antivirals (DAAs) or peginterferon/ribavirin who achieved sustained virologic response [SVR, defined as undetectable HCV RNA throughout 12 wk (SVR12) for the DAA group or 24 wk (SVR24) for the interferon group after completion of antiviral therapy] were enrolled since 2003. The primary endpoint was the development of new-onset HCC. Standard HCC surveillance (abdominal ultrasound and α-fetoprotein) was performed every six months during the follow-up. Overall, 64 serum cytokines were detected by the multiplex immunoassay at baseline and 24 wk after end-of-treatment., Results: HCC developed in 12 of the 97 patients over 459 person-years after HCV eradication. In univariate analysis, the Fibrosis-4 index (FIB-4), hemoglobin A1c (HbA1c), the dynamics of tumor necrosis factor-α (TNF-α), and TNF-like weak inducer of apoptosis (TWEAK) after antiviral therapy were significant HCC predictors. The multivariate Cox regression model showed that ΔTNF-α (≤ -5.7 pg/mL) was the most important risk factor for HCC (HR = 11.54, 95%CI: 2.27-58.72, P = 0.003 in overall cases; HR = 9.98, 95%CI: 1.88-52.87, P = 0.007 in the interferon group). An HCC predictive model comprising FIB-4, HbA1c, ΔTNF-α, and ΔTWEAK had excellent performance, with 3-, 5-, 10-, and 13-year areas under the curve of 0.882, 0.864, 0.903, and 1.000, respectively. The 5-year accumulative risks of HCC were 0%, 16.9%, and 40.0% in the low-, intermediate-, and high-risk groups, respectively., Conclusion: Downregulation of serum TNF-α significantly increases the risk of HCC after HCV eradication. A predictive model consisting of cytokine kinetics could ameliorate personalized HCC surveillance strategies for post-SVR HCV patients., Competing Interests: Conflict-of-interest statement: The authors declare that they have no competing interests., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

Objective: HCV prevails in uremic haemodialysis patients. The current study aimed to achieve HCV microelimination in haemodialysis centres through a comprehensive outreach programme., Design: The ERASE-C Campaign is an outreach programme for the screening, diagnosis and group treatment of HCV encompassing 2323 uremic patients and 353 medical staff members from 18 haemodialysis centres. HCV-viremic subjects were linked to care for directly acting antiviral therapy or received on-site sofosbuvir/velpatasvir therapy. The objectives were HCV microelimination (>80% reduction of the HCV-viremic rate 24 weeks after the end of the campaign in centres with ≥90% of the HCV-viremic patients treated) and 'No-C HD' (no HCV-viremic subjects at the end of follow-up)., Results: At the preinterventional screening, 178 (7.7%) uremic patients and 2 (0.6%) staff members were HCV-viremic. Among them, 146 (83.9%) uremic patients received anti-HCV therapy (41 link-to-care; 105 on-site sofosbuvir/velpatasvir). The rates of sustained virological response (SVR12, undetectable HCV RNA 12 weeks after the end of treatment) in the full analysis set and per-protocol population were 89.5% (94/105) and 100% (86/86), respectively, in the on-site treatment group, which were comparable with the rates of 92.7% (38/41) and 100% (38/38), respectively, in the link-to-care group. Eventually, the HCV-viremic rate decreased to 0.9% (18/1,953), yielding an 88.3% reduction from baseline. HCV microelimination and 'No-C HD' were achieved in 92.3% (12/13) and 38.9% (7/18) of the haemodialysis centres, respectively., Conclusion: Outreach strategies with mass screenings and on-site group treatment greatly facilitated HCV microelimination in the haemodialysis population., Clinicaltrialsgov Identifier: NCT03803410 and NCT03891550., Competing Interests: Competing interests: M-LY: research support from Abbvie, Abbott, BMS, Gilead, Merck and Roche. Consultant for Abbvie, Abbott, Ascletis, BMS, Gilead, J&J, Merck, Novartis, Pharmaessential and Roche. Speaker for Abbvie, Abbott, Ascletis, BMS, Gilead, Merck, Pharmaessential and Roche. C-FH: speaker for Abbvie, BMS, Gilead, Merck and Roche., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The World Health Organization (WHO) set out to eliminate hepatitis C virus (HCV) infection by 2030, a goal Taiwan might achieve before 2025. Using effective direct antiviral agents (DAAs) against chronic hepatitis C (CHC) in Taiwan, the treatment of CHC has been initiated in rural areas. Here, we aimed to elucidate the clinical and virological characteristics of HCV infection, and the treatment efficacy of DAAs in patients from Pingtung county in southern Taiwan., Methods: A total of 152 chronic hepatitis patients treated with DAAs were consecutively enrolled. Baseline characteristics and therapeutic efficacy were evaluated., Results: HCV genotype 2 was the most common viral genotype (39.5%), followed by 1b (36.8%), 6 (10.5%), and 1a (9.2%). The sustained virological response (SVR) rate was 98.7%. Hakka patients accounted for 22.4% of the study cohort, of which 14.7% had HCV genotype 6. There were no differences in clinical characteristics between Hakka and non-Hakka patients. Patients with HCV genotype 6 were younger in age (OR/CI: 0.95/0.91-1.00, p = 0.04) and composed of more people who inject drugs (PWID) (OR/CI: 17.6/3.6-85.5, p <0.001), when compared with other patients., Conclusion: We demonstrated that DAA therapy can achieve a 98.7% SVR rate among CHC patients in Pingtung county of southern Taiwan, with a relative higher prevalence of genotype 6. The most important factor attributed to genotype 6 infection was PWID., Competing Interests: Conflicts of interest: The authors declare that they have no conflicts of interest related to the subject matter or materials discussed in this article., (Copyright © 2020, the Chinese Medical Association.)

Background/aims: Direct-acting antivirals (DAAs) have been approved for hepatitis C virus (HCV) treatment in patients with end-stage renal disease (ESRD) on hemodialysis. Nevertheless, the complicated comedications and their potential drug-drug interactions (DDIs) with DAAs might limit clinical practice in this special population., Methods: The number, class, and characteristics of comedications and their potential DDIs with five DAA regimens were analyzed among HCV-viremic patients from 23 hemodialysis centers in Taiwan., Results: Of 2,015 hemodialysis patients screened in 2019, 169 patients seropositive for HCV RNA were enrolled (mean age, 65.6 years; median duration of hemodialysis, 5.8 years). All patients received at least one comedication (median number, 6; mean class number, 3.4). The most common comedication classes were ESRD-associated medications (94.1%), cardiovascular drugs (69.8%) and antidiabetic drugs (43.2%). ESRD-associated medications were excluded from DDI analysis. Sofosbuvir/velpatasvir/voxilaprevir had the highest frequency of potential contraindicated DDIs (red, 5.6%), followed by glecaprevir/pibrentasvir (4.0%), sofosbuvir/ledipasvir (1.3%), sofosbuvir/velpatasvir (1.3%), and elbasvir/grazoprevir (0.3%). For potentially significant DDIs (orange, requiring close monitoring or dose adjustments), sofosbuvir/velpatasvir/voxilaprevir had the highest frequency (19.9%), followed by sofosbuvir/ledipasvir (18.2%), glecaprevir/pibrentasvir (12.6%), sofosbuvir/velpatasvir (12.6%), and elbasvir/grazoprevir (7.3%). Overall, lipid-lowering agents were the most common comedication class with red-category DDIs to all DAA regimens (n=62), followed by cardiovascular agents (n=15), and central nervous system agents (n=10)., Conclusion: HCV-viremic patients on hemodialysis had a very high prevalence of comedications with a broad spectrum, which had varied DDIs with currently available DAA regimens. Elbasvir/grazoprevir had the fewest potential DDIs, and sofosbuvir/velpatasvir/voxilaprevir had the most potential DDIs.

Background/aims: Obstacles exist in facilitating hepatitis C virus (HCV) care cascade. To increase timely and accurate diagnosis, disease awareness and accessibility, in-hospital HCV reflex testing followed by automatic appointments and a late call-back strategy (R.N.A. model) was applied. We aimed to compare the HCV treatment rate of patients treated with this strategy compared to those without., Methods: One hundred and twenty-five anti-HCV seropositive patients who adopted the R.N.A. model in 2020 and another 1,396 controls treated in 2019 were enrolled to compare the gaps in accurate HCV RNA diagnosis to final treatment allocation., Results: The HCV RNA testing rate was significantly higher in patients who received reflex testing than in those without reflex testing (100% vs. 84.8%, P<0.001). When patients were stratified according to the referring outpatient department, a significant improvement in the HCV RNA testing rate was particularly noted in patients from non-hepatology departments (100% vs. 23.3%, P<0.001). The treatment rate in HCV RNA seropositive patients was 83% (83/100) after the adoption of the R.N.A. model, among whom 96.1% and 73.9% of patients were from the hepatology and non-hepatology departments, respectively. Compared to subjects without R.N.A. model application, a significant improvement in the treatment rate was observed for patients from non-hepatology departments (73.9% vs. 27.8%, P=0.001). The application of the R.N.A. model significantly increased the in-hospital HCV treatment uptake from 6.4% to 73.9% for patients from non-hepatology departments (P<0.001)., Conclusion: The care cascade increased the treatment uptake and set up a model for enhancing in-hospital HCV elimination.