During extended warranty(EW)period,maintenance events play a key role in controlling the product systems within normal operations.However,the modelling of failure process and maintenance optimization is complicated ow...During extended warranty(EW)period,maintenance events play a key role in controlling the product systems within normal operations.However,the modelling of failure process and maintenance optimization is complicated owing to the complex features of the product system,namely,components of the multi-component system are interdependent with each other in some form.For the purpose of optimizing the EW pricing decision of the multi-component system scientifically and rationally,taking the series multi-component system with economic dependence sold with EW policy as a research object,this paper optimizes the imperfect preventive maintenance(PM)strategy from the standpoint of EW cost.Taking into consideration adjusting the PM moments of the components in the system,a group maintenance model is developed,in which the system is repaired preventively in accordance with a specified PM base interval.In order to compare with the system EW cost before group maintenance,the system EW cost model before group maintenance is developed.Numerical example demonstrates that offering group maintenance programs can reduce EW cost of the system to a great extent,thereby reducing the EW price,which proves to be a win-win strategy to manufacturers and users.展开更多
BACKGROUND Ewing sarcoma(ES)is a malignant neoplasm of neuroectodermal origin and is commonly observed in children and young adults.The musculoskeletal system is the main body system impacted and ES is rarely seen in ...BACKGROUND Ewing sarcoma(ES)is a malignant neoplasm of neuroectodermal origin and is commonly observed in children and young adults.The musculoskeletal system is the main body system impacted and ES is rarely seen in the visceral organs particularly the adrenal gland.AIM To present a comprehensive review of primary adrenal ES,with emphasis on diagnosis,therapy and oncological outcomes.METHODS A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020.PubMed/MEDLINE,EMBASE and Google Scholar bibliographic databases were searched to identify articles from 1989 to 2022 and included patients with ES/primitive neuroectodermal tumor(PNET)of the adrenal gland.PubMed,Google Scholar and EMBASE medical databases were searched,combining the terms“adrenal”,“ES”and“PNET”.Demographic,clinical,pathological and oncological data of patients were analyzed by SPSS version 29.0.RESULTS A total of 52 studies were included for review(47 case reports and 5 case series)with 66 patients reported to have primary adrenal ES.Mean age at diagnosis was 26.4±15.4 years(37.9%males,57.6%females,sex not reported in 3 cases).The most frequent complaint was abdominal/flank pain or discomfort(46.4%)followed by a palpable mass(25.0%),and the average duration of symptoms was 2.6±3.1 mo.The imaging modality of choice was computed tomography scan(81.5%),followed by magnetic resonance imaging(20.4%).Preoperative staging revealed that 17 tumors(27.9%)were metastatic and 14 patients had inferior vena cava or renal vein neoplastic thrombus at initial diagnosis.Open adrenalectomy was performed in the majority of cases(80.0%),of which 27.9%required more extensive resection.Minimally invasive surgery was attempted in 8.2%of tumors.Complete surgical resection was achieved in 89.4%of the patients.Adjuvant therapy was administered to 32 patients,in the form of chemotherapy(62.5%),radiotherapy(3.1%)or combination(34.4%).Median overall survival was 15 mo and 24-mo overall survival was 40.5%.Median disease-free survival was 10 mo and 24-mo disease-free survival was 33.3%.CONCLUSION The significant progress in molecular biology and genetics of ES does not reflect on patient outcomes.ES remains an aggressive tumor with a poor prognosis and high mortality.展开更多
目的采用一测多评(QAMS)法同时测定法制半夏曲中肌苷、鸟苷、腺苷等11种成分含量,并建立其灰色关联度分析(GRA)联合熵权逼近理想解排序分析法(EW-TOPSIS)综合质量评价方法。方法采用Shimadzu C 18色谱柱;乙腈-0.5%醋酸为流动相,梯度洗脱...目的采用一测多评(QAMS)法同时测定法制半夏曲中肌苷、鸟苷、腺苷等11种成分含量,并建立其灰色关联度分析(GRA)联合熵权逼近理想解排序分析法(EW-TOPSIS)综合质量评价方法。方法采用Shimadzu C 18色谱柱;乙腈-0.5%醋酸为流动相,梯度洗脱,流速1.0 mL·min-1;检测波长254和290 nm。以对甲氧基肉桂酸乙酯为内参比物质,计算其他10个成分的相对校正因子(RCF),测定各成分含量。采用GRA联合EW-TOPSIS模型对法制半夏曲进行综合质量评价。结果法制半夏曲中11种成分在一定浓度范围内线性关系良好,相关系数均>0.999;平均加样回收率96.94%~100.12%(RSD<2.0%,n=9);QAMS与外标法(ESM)实测值无明显差异。GRA模型相对关联度0.2903~0.6187,EW-TOPSIS模型相对接近度0.2114~0.6343;GRA和EW-TOPSIS模型综合评价结果基本一致。结论QAMS法便捷、准确,可用于法制半夏曲多指标成分定量控制,GRA联合EW-TOPSIS模型可用于法制半夏曲综合质量评价。展开更多
基金supported by the National Natural Science Foundation of China(71871219).
文摘During extended warranty(EW)period,maintenance events play a key role in controlling the product systems within normal operations.However,the modelling of failure process and maintenance optimization is complicated owing to the complex features of the product system,namely,components of the multi-component system are interdependent with each other in some form.For the purpose of optimizing the EW pricing decision of the multi-component system scientifically and rationally,taking the series multi-component system with economic dependence sold with EW policy as a research object,this paper optimizes the imperfect preventive maintenance(PM)strategy from the standpoint of EW cost.Taking into consideration adjusting the PM moments of the components in the system,a group maintenance model is developed,in which the system is repaired preventively in accordance with a specified PM base interval.In order to compare with the system EW cost before group maintenance,the system EW cost model before group maintenance is developed.Numerical example demonstrates that offering group maintenance programs can reduce EW cost of the system to a great extent,thereby reducing the EW price,which proves to be a win-win strategy to manufacturers and users.
文摘BACKGROUND Ewing sarcoma(ES)is a malignant neoplasm of neuroectodermal origin and is commonly observed in children and young adults.The musculoskeletal system is the main body system impacted and ES is rarely seen in the visceral organs particularly the adrenal gland.AIM To present a comprehensive review of primary adrenal ES,with emphasis on diagnosis,therapy and oncological outcomes.METHODS A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020.PubMed/MEDLINE,EMBASE and Google Scholar bibliographic databases were searched to identify articles from 1989 to 2022 and included patients with ES/primitive neuroectodermal tumor(PNET)of the adrenal gland.PubMed,Google Scholar and EMBASE medical databases were searched,combining the terms“adrenal”,“ES”and“PNET”.Demographic,clinical,pathological and oncological data of patients were analyzed by SPSS version 29.0.RESULTS A total of 52 studies were included for review(47 case reports and 5 case series)with 66 patients reported to have primary adrenal ES.Mean age at diagnosis was 26.4±15.4 years(37.9%males,57.6%females,sex not reported in 3 cases).The most frequent complaint was abdominal/flank pain or discomfort(46.4%)followed by a palpable mass(25.0%),and the average duration of symptoms was 2.6±3.1 mo.The imaging modality of choice was computed tomography scan(81.5%),followed by magnetic resonance imaging(20.4%).Preoperative staging revealed that 17 tumors(27.9%)were metastatic and 14 patients had inferior vena cava or renal vein neoplastic thrombus at initial diagnosis.Open adrenalectomy was performed in the majority of cases(80.0%),of which 27.9%required more extensive resection.Minimally invasive surgery was attempted in 8.2%of tumors.Complete surgical resection was achieved in 89.4%of the patients.Adjuvant therapy was administered to 32 patients,in the form of chemotherapy(62.5%),radiotherapy(3.1%)or combination(34.4%).Median overall survival was 15 mo and 24-mo overall survival was 40.5%.Median disease-free survival was 10 mo and 24-mo disease-free survival was 33.3%.CONCLUSION The significant progress in molecular biology and genetics of ES does not reflect on patient outcomes.ES remains an aggressive tumor with a poor prognosis and high mortality.
文摘目的采用一测多评(QAMS)法同时测定法制半夏曲中肌苷、鸟苷、腺苷等11种成分含量,并建立其灰色关联度分析(GRA)联合熵权逼近理想解排序分析法(EW-TOPSIS)综合质量评价方法。方法采用Shimadzu C 18色谱柱;乙腈-0.5%醋酸为流动相,梯度洗脱,流速1.0 mL·min-1;检测波长254和290 nm。以对甲氧基肉桂酸乙酯为内参比物质,计算其他10个成分的相对校正因子(RCF),测定各成分含量。采用GRA联合EW-TOPSIS模型对法制半夏曲进行综合质量评价。结果法制半夏曲中11种成分在一定浓度范围内线性关系良好,相关系数均>0.999;平均加样回收率96.94%~100.12%(RSD<2.0%,n=9);QAMS与外标法(ESM)实测值无明显差异。GRA模型相对关联度0.2903~0.6187,EW-TOPSIS模型相对接近度0.2114~0.6343;GRA和EW-TOPSIS模型综合评价结果基本一致。结论QAMS法便捷、准确,可用于法制半夏曲多指标成分定量控制,GRA联合EW-TOPSIS模型可用于法制半夏曲综合质量评价。
