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A Note on an Order Level Inventory Model with Varying Two-Phased Demand and Time-Proportional Deterioration
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作者 Sephali Mohanty Trailokyanath Singh +1 位作者 Sudhansu Sekhar Routary Chinmayee Naik 《American Journal of Operations Research》 2024年第1期59-73,共15页
The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. Th... The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out. 展开更多
关键词 Deteriorating Items EOQ (Economic Order Quantity) INVENTORY Time-Proportional deterioration Two-Phased Demand
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Risk Factors of the Progression of Renal Function Deterioration Among Patients with Diabetic Nephropathy
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作者 Nan Bao Tong Ding +2 位作者 Yanting Gao Yanting Zhu Pengjie Zhang 《Journal of Clinical and Nursing Research》 2024年第1期7-12,共6页
Objective:To explore the risk factors for the progression of renal function deterioration in patients with diabetic nephropathy(DN).Methods:The clinical data and biochemical indexes of 100 diabetic patients admitted t... Objective:To explore the risk factors for the progression of renal function deterioration in patients with diabetic nephropathy(DN).Methods:The clinical data and biochemical indexes of 100 diabetic patients admitted to our hospital from October 2021 to October 2022 were retrospectively analyzed.The patients were divided into a DN group,which consisted of 55 cases,and a nondiabetic nephropathy group(NDN),which consisted of 45 cases.The urinary microalbumin to creatinine ratio,the clinical data(gender,age,duration of the disease,and BMI),and the biochemical indexes(triglycerides[TG],low-density lipoprotein cholesterol[LDL-C],high-density lipoprotein cholesterol[HDL-C],total cholesterol[TC],glycated hemoglobin A1c[HbA1c],systolic blood pressure[SBP],diastolic blood pressure[DBP])of the two groups were compared.Subsequently,the risk factors related to the progression of renal function deterioration in DN were analyzed through multifactorial logistic regression analysis.Results:No statistically significant difference was observed in the comparison of gender,age,BMI,LDL-C,and DBP between the two groups(P>0.05).The DN group demonstrated a longer disease duration and higher SBP,TC,HDL-C,HbA1c,and TG compared to the NDN group(P<0.05).Through multifactorial logistic regression analysis,it was found that the duration of the disease,the TC,the HDL-C,the HbA1c,the TG,and the SBP were independent risk factors of the deterioration of renal function in DN patients.Conclusion:Other than conventional indicators,TC,HDL-C,HbA1c,TG,and SBP are also crucial indicators in determining the progression of renal function deterioration in DN patients. 展开更多
关键词 Diabetic nephropathy Renal function deterioration Risk factors
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Accelerated Deterioration Mechanism and Reliability Evaluation of Concrete in Saline Soil Area
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作者 付勇 乔宏霞 +2 位作者 HAKUZWEYEZU Theogene QIAO Guobin GUO Fei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期582-590,共9页
To reveal the deterioration mechanism and service life of concrete durability in the western saline soil area,the indoor accelerated test of the concrete specimen was simulated in the coupled environment of salt erosi... To reveal the deterioration mechanism and service life of concrete durability in the western saline soil area,the indoor accelerated test of the concrete specimen was simulated in the coupled environment of salt erosion and dry-wet cycles in the west saline soil area of China.The deterioration mechanism of concrete durability was revealed through the relative dynamic elastic modulus,relative quality evaluation parameters,SEM,and XRD evaluation indexes.Random Wiener distribution function was used for modeling life prediction.The results show that the relative dynamic elastic modulus evaluation parameter as an evaluation index of concrete durability under various environmental coupling effects is more reliable than the relative quality,there were holes and cracks in the concrete,and needle-like and layered crystals grow from the internal cracks.The corrosion products include ettringite,gypsum and other expansive crystals and non-gelling Mg(OH)_(2);the expansion stress caused by physical,chemical reaction,and temperature change under the action of drywet cycle aggravates the formation and development of cracks.The random Wiener distribution function can describe the degradation process of concrete specimen durability,and the established concrete reliability function can intuitively reflect the service life of concrete specimens. 展开更多
关键词 CONCRETE saline soil area service prediction random wiener DURABILITY deterioration mechanism
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The law of strength damage and deterioration of jointed sandstone after dry-wet cycles
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作者 WANG Gui-lin ZHANG Tian-yu ZHANG Liang 《Journal of Mountain Science》 SCIE CSCD 2023年第4期1170-1182,共13页
Under the periodic rise and fall of the water level in the Three Gorges Reservoir in China,the rock mass in the ebb and flow zone of the slope is always in a state of a dry-wet cycle.In order to explore the influence ... Under the periodic rise and fall of the water level in the Three Gorges Reservoir in China,the rock mass in the ebb and flow zone of the slope is always in a state of a dry-wet cycle.In order to explore the influence of dry-wet cycle on mechanical properties of jointed sandstone,the triaxial and uniaxial compression tests of dry-wet cycle of jointed sandstone were carried out.For the experiment,four groups of samples with different numbers of joints were set up,and the jointed rock samples were subjected to 20 dry-wet cycles.Using both the triaxial compression test and the Mohr-Coulomb(M-C)rock fracture criterion,the strength envelope of the sandstone samples was fitted,and their strength degradation was further analyzed and studied.The results show that:(1)The peak intensity and elastic modulus of the sandstone samples decrease with increased number of dry-wet cycles.(2)The total deterioration of mechanical properties of intact rock samples is bigger than that of jointed sandstone samples as the number of dry-wet cycles increases.(3)With the increase of confining pressure,the peak intensity of intact sandstone samples increases much more than that of jointed sandstone samples,which indicates that joints and their numbers have obvious influence.(4)Joints and their numbers play an important role in guiding the damage effects of sandstone samples,which weaken the damage caused by dry-wet cycles.Therefore,the envelope of the M-C strength criterion of intact sandstone samples moves more than that of jointed sandstone samples. 展开更多
关键词 Jointed sandstone Dry-wet cycle Triaxial compression Strength damage deterioration mechanism
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Influence of Harvest Periods on Cassava (Manihot esculenta Crantz) Agronomic Traits and Physiological Response to Post-Harvest Physiological Deterioration
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作者 Astride Stéphanie Mouafi Djabou Herman Pascal Kounty Ewane +4 位作者 Victor Jos Evina Eyamo Franklin Tounkam Ketchiemo Priscila Gonzales Figueiredo Nicolas Niemenak Libert Brice Tonfack 《American Journal of Plant Sciences》 CAS 2023年第1期89-103,共15页
Cassava (Manihot esculenta Crantz) is the third largest source of calories in tropical countries and the sixth most important food crop in the World. However, the short shelf life of its storage roots after harvest du... Cassava (Manihot esculenta Crantz) is the third largest source of calories in tropical countries and the sixth most important food crop in the World. However, the short shelf life of its storage roots after harvest due to a rapid post-harvest physiological deterioration (PPD) makes the roots to be considered as a risky product to market. The objectives of this work were to investigate the influence of two harvest periods on cassava agronomic parameters and their physiological response to PPD. Three cassava cultivars 96/1414, I070593 and LMR were selected for the experiment and harvested at 10 and 12 months after planting (MAP). The response to PPD was assessed during storage at 0, 3, 8 and 15 days after harvest (DAH). Total proteins content, soluble sugars and starch, total polyphenols compounds, polyphenoloxidase and peroxidase activities were recorded during storage. Results showed large variation among the parameters at the two harvest periods across the cultivars. High number of tubers was recorded in all the cultivars at 12 MAP and a significant increase in storage roots length was observed in 96/1414 and LMR from 10 MAP to 12 MAP (25 ± 5.1 to 41.3 ± 5.9 and 22.6 ± 3.3 to 27.9 ± 4.8) respectively. A reduction of about 49% of tubers weight was observed in I070593 from 10 to 12 MAP while an increase of about 36% and 11% were recorded in LMR and 96/1414 respectively. Tubers from I070593 showed less susceptibility to PPD when harvested at 10 MAP compared to those from LMR and 96/1414 where less susceptibility to PPD were recorded at 12 MAP. An increase in soluble sugars content, total proteins content and peroxidase activity subsequently to a decrease in starch content were recorded during storage from 8 to 15 days after harvest especially at 10 MAP in I070593 and at 12 MAP in LMR and 96/1414. High content of total phenolic compounds and less activity of polyphenol oxidase were correlated to PPD susceptibility. This work opens a new insight issue of the consideration of the appropriate harvest time of the cultivars as a tool to better control the onset of postharvest physiological deterioration. 展开更多
关键词 Manihot esculenta Harvest Period Post-Harvest deterioration Agronomic and Biochemical Parameters
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The Deterioration of the Compson Family——From Character's Perspective
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作者 谭幸 《海外英语》 2013年第5X期205-207,共3页
The Sound and the Fury is William Faulkner's greatest work; four narrators tell the story of the deterioration of the Compson family from different perspective, exploring the cause of deterioration indirectly. The... The Sound and the Fury is William Faulkner's greatest work; four narrators tell the story of the deterioration of the Compson family from different perspective, exploring the cause of deterioration indirectly. The novel centers on Caddy's moral decay from different perspective. The thesis analyzes the processing fall of the Compson family through the analysis of three characters, Caddy, Quentin, and Jason. Caddy's deterioration is closely related to her loss of virginity, and her impending wedding causes Quentin to commit suicide who loves her deeply and possessively. However, Jason is heartless who he does not care his family. His tragedy lies in the decay of human nature. The thesis gives the general cause of the downfall of the family and readers will have a general concept of the family's deterioration. 展开更多
关键词 The SOUND and the Fury SYMBOL deterioration destin
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The Deterioration of the English Language
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作者 尹轶群 《海外英语》 2013年第22期300-301,共2页
The English language has been deteriorating because of the modern e-mail and chat room language abbreviations,in corporation of different dialects depending on culture,and the inappropriate use of words as well as inc... The English language has been deteriorating because of the modern e-mail and chat room language abbreviations,in corporation of different dialects depending on culture,and the inappropriate use of words as well as incorrect spelling.If we want to keep English language from deterioration,we should take advantage of the advances in technology and to learn about other cultures dialects,but we should keep the proper written and spoken English in mind. 展开更多
关键词 ENGLISH LANGUAGE deterioration echnology DIALECTS
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Numerical study on non-uniform heat transfer deterioration of supercritical RP-3 aviation kerosene in a horizontal tube 被引量:7
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作者 Yanhong Wang Yingnan Lu +1 位作者 Sufen Li Ming Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第6期1542-1557,共16页
The convective heat transfer of supercritical-pressure RP-3(Rocket Propellant 3)aviation kerosene in a horizontal circular tube has been numerically studied,focusing mainly on the non-uniform heat transfer deteriorati... The convective heat transfer of supercritical-pressure RP-3(Rocket Propellant 3)aviation kerosene in a horizontal circular tube has been numerically studied,focusing mainly on the non-uniform heat transfer deterioration along the circumferential direction.The governing equations of mass,momentum and energy have been solved using the pressure-based segregated solver based on the finite volume method.The re-normalization group(RNG)k-εturbulence model with an enhanced wall treatment was selected.Considering the heat conduction in the solid wall,the mechanism of heat transfer deterioration and the buoyancy effect on deteriorated heat transfer were discussed.The evolution of secondary flow was analyzed.Effects of the outer-wall heat flux,mass flux,pressure and tube thermal conductivity on heat transfer were investigated.Moreover,the buoyancy criterion and the heat transfer correlation were obtained.Results indicate that the poor flow performance of near-wall fluid causes the pseudo-film boiling,further leads to the heat transfer deterioration.The strong buoyancy has an effect of enhancing the heat transfer at the bottom of tube,and weakening the heat transfer at the top of tube,which results in the non-uniform inner-wall temperature and heat flux distributions.Decreasing the ratio of outer-wall heat flux and mass flux,increasing the pressure could weaken the heat transfer difference along the circumferential direction,while the effect of thermal conductivity of tube on the circumferential parameters distributions is more complicated.When the buoyancy criterion of(Grq/Grth)max≤0.8 is satisfied,the effect of buoyancy could be ignored.The new correlations work well for non-uniform heat transfer predictions. 展开更多
关键词 Supercritical pressure Aviation kerosene Non-uniform heat transfer Heat transfer deterioration BUOYANCY Prediction correlation
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Stress-Strength Structural Reliability Model with a Stochastic Strength Aging Deterioration Process 被引量:5
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作者 叶欢 陈庆华 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期847-849,共3页
A stress-strength structural reliability model was proposed with a stochastic strength aging deterioration process. In structural engineering,the deterioration of structure's strength should be the total of the de... A stress-strength structural reliability model was proposed with a stochastic strength aging deterioration process. In structural engineering,the deterioration of structure's strength should be the total of the deterioration owing to continual wear, fatigue,corrosion,etc.,and the abrupt deterioration as a result of randomly variable loads. The deterioration of structure's strength should be influenced by both the internal deterioration owing to direct wear and the external deterioration due to randomly variable loads.Meanwhile,the load process was given as Poisson square wave process. The reliability was derived using stress-strength interference theory. In particular,the reliability was also given when random variables followed the normal distribution. 展开更多
关键词 stress-strength interference internal deterioration external deterioration randomly variable loads POISSON SQUARE wave process
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Effect of salts on earthen materials deterioration after humidity cycling 被引量:3
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作者 沈云霞 谌文武 +1 位作者 匡静 杜伟飞 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期796-806,共11页
Salt weathering leads to destruction of many valuable cultural heritage monuments and porous building material. The present study aims at providing more laboratory evidence for evaluating the effects of salt precipita... Salt weathering leads to destruction of many valuable cultural heritage monuments and porous building material. The present study aims at providing more laboratory evidence for evaluating the effects of salt precipitation on the deterioration process. In view of this, the remoulded soil specimens were mixed with three kinds of salts(i.e., NaCl, Na_2SO_4 and their mixture) with different salt concentrations, and the specimens were kept in environment cabinet for undergoing different wet-dry cycles. After each cycle, the ultrasound velocity measurements were employed to monitor the deterioration process. For the specimens that have suffered three wet-dry cycles, the mechanical properties(i.e. shear strength and compression strength) were determined to evaluate the degree of deterioration. Furthermore, considering the realistic conservation environment of earthen sites, mechanical stability of these specimens against sediment-carrying wind erosion was conducted in a wind tunnel. These experiments results indicate that the overall average velocities of the specimens after the third cycle are significantly lower than those subjected to only one cycle. Ultrasound velocity, mechanical strength and wind erosion rate decrease when salt content increases. However, the internal friction angle increases firstly, and then decreases with the increase in salt content added to the specimens. Na_2SO_4 contributes most of the surface deterioration, while NaCl plays little role in the deterioration. The damage potential of the salt mixture is less obvious and largely dependent on the crystallisation location. 展开更多
关键词 earthen archaeological sites wet-dry cycles deterioration SALT content SALT CRYSTALLIZATION
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Experimental Study on Deterioration of Concrete Strength under Different Sub-high Temperature Cycles 被引量:3
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作者 赵顺波 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第z1期53-57,共5页
Tests were carried out to study the strength deterioration of concrete cooled in air or by water after sub-high temperature at different level and varying with cycles. It is proved that the cross-shaped cracks turned ... Tests were carried out to study the strength deterioration of concrete cooled in air or by water after sub-high temperature at different level and varying with cycles. It is proved that the cross-shaped cracks turned up and extended little by little on the surface of specimen subjected to repeat sub-high temperature, the splitting failure is characterized by cross-shaped cracks after 30 cycles, the concrete strengths decrease rapidly at early stage and to be steady subsequently with the increase of the temperature cycles,the splitting-tensile strength is more sensitive to temperature cycles than the compressive strength, the decline of concrete strength is mainly controlled by the maximum temperature having reached, the ultrasonic velocity in concrete is also declined. On the basis of test results, the mechanisms of sub-high temperature to the strength deterioration of concrete are analyzed.The formulas for calculating the compressive and splitting-tensile strength of concrete relating to the variation of temperature are proposed. 展开更多
关键词 sub-high temperature deterioration cooled by water COMPRESSIVE STRENGTH splitting-tensile STRENGTH ULTRASONIC WAVE
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Peripheral Artery Disease and Risk of Fibrosis Deterioration in Nonalcoholic Fatty Liver Disease:A Prospective Investigation 被引量:2
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作者 ZHU Wen DENG Chan Juan +10 位作者 XUAN Li Ping DAI Hua Jie ZHAO Zhi Yun WANG Tian Ge LI Mian LU Jie Li XU Yu CHEN Yu Hong WANG Wei Qing BI Yu Fang XU Min 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第4期217-226,共10页
Objective Liver fibrosis is an important predictor of mortality in nonalcoholic fatty liver disease(NAFLD).Peripheral artery disease(PAD)and liver fibrosis share many common metabolic dysfunctions.We aimed to explore ... Objective Liver fibrosis is an important predictor of mortality in nonalcoholic fatty liver disease(NAFLD).Peripheral artery disease(PAD)and liver fibrosis share many common metabolic dysfunctions.We aimed to explore the association between PAD and risk of fibrosis deterioration in NAFLD patients.Methods The study recruited 1,610 NAFLD patients aged≥40 years from a well-defined community at baseline in 2010 and followed up between August 2014 and May 2015.Fibrosis deterioration was defined as the NAFLD fibrosis score(NFS)status increased to a higher category at the follow-up visit.PAD was defined as an ankle-brachial index of<0.90 or>1.40.Results During an average of 4.3 years’follow-up,618 patients progressed to a higher NFS category.PAD was associated with 92%increased risk of fibrosis deterioration[multivariable-adjusted odds ratio(OR):1.92,95%confidence interval(CI):1.24,2.98].When stratified by baseline NFS status,the OR for progression from low to intermediate or high NFS was 1.74(95%CI:1.02,3.00),and progression from intermediate to high NFS was 2.24(95%CI:1.05,4.80).There was a significant interaction between PAD and insulin resistance(IR)on fibrosis deterioration(P for interaction=0.03).As compared with non-PAD and non-IR,the coexistence of PAD and IR was associated with a 3.85-fold(95%CI:2.06,7.18)increased risk of fibrosis deterioration.Conclusion PAD is associated with an increased risk of fibrosis deterioration in NAFLD patients,especially in those with IR.The coexistence of PAD and IR may impose an interactive effect on the risk of fibrosis deterioration. 展开更多
关键词 Ankle-brachial index Nonalcoholic fatty liver disease Fibrosis deterioration NAFLD fibrosis score Insulin resistance
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Field mold stress induced catabolism of storage reserves in soybean seed and the resulting deterioration of seed quality in the field 被引量:1
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作者 DENG Jun-cai LI Xiao-man +15 位作者 XIAO Xin-li WU Hai-jun YANG Cai-qiong LONG Xi-yang ZHANG Qi-hui Nasir IQBAL WANG Xiao-chun YONG Tai-wen DU Jun-bo YANG Feng LIU Wei-guo ZHANG Jing WU Xiao-ling WU Yu-shan YANG Wen-yu LIU Jiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第2期336-350,共15页
Excessive rainfall provides a favorable condition for field mold infection of plants, which triggers field mold(FM) stress. If FM stress occurs during the late maturation stage of soybean seed, it negatively affects s... Excessive rainfall provides a favorable condition for field mold infection of plants, which triggers field mold(FM) stress. If FM stress occurs during the late maturation stage of soybean seed, it negatively affects seed yield and quality. To investigate the responses of soybean seed against FM stress and identify the underlying biochemical pathways involved, a greenhouse was equipped with an artificial rain producing system to allow the induction of mold growth on soybean seed. The induced quality changes and stress responses were revealed on the levels of both transcriptome and metabolome. The results showed that soybean seeds produced under FM stress conditions had an abnormal and inferior appearance, and also contained less storage reserves, such as protein and polysaccharide. Transcriptional analysis demonstrated that genes involved in amino acid metabolism, glycolysis, tricarboxylic acid, β-oxidation of fatty acids, and isoflavone biosynthesis were induced by FM stress. These results were supported by a multiple metabolic analysis which exhibited increases in the concentrations of a variety of amino acids, sugars, organic acids, and isoflavones, as well as reductions of several fatty acids. Reprogramming of these metabolic pathways mobilized and consumed stored protein, sugar and fatty acid reserves in the soybean seed in order to meet the energy and substrate demand on the defense system, but led to deterioration of seed quality. In general, FM stress induced catabolism of storage reserves and diminished the quality of soybean seed in the field. This study provides a more profound insight into seed deterioration caused by FM stress. 展开更多
关键词 seed deterioration seed quality primary metabolism storage reserves resistance
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Parallel-batch scheduling with deterioration and rejection on a single machine 被引量:1
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作者 LI Da-wei LU Xi-wen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2020年第2期141-156,共16页
The single machine parallel-batch scheduling with deteriorating jobs and rejection is considered in this paper.A job is either rejected,in which a rejection penalty should be paid,or accepted and processed on the mach... The single machine parallel-batch scheduling with deteriorating jobs and rejection is considered in this paper.A job is either rejected,in which a rejection penalty should be paid,or accepted and processed on the machine.Each job’s processing time is an increasing linear function of its starting time.The machine can process any number of jobs simultaneously as a batch.The processing time of a batch is equal to the largest processing time of the jobs in the batch.The objectives are to minimize the makespan and the total weighted completion time,respectively,under the condition that the total rejection penalty cannot exceed a given upper bound Q.We show that both problems are NP-complete and present dynamic programming algorithms and fully polynomial time approximation schemes(FPTASs)for the considered problems. 展开更多
关键词 parallel-batch scheduling REJECTION deterioration FPTAS NP-COMPLETE
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An Inventory Model for Deteriorating Items with Generalised Exponential Decreasing Demand, Constant Holding Cost and Time-Varying Deterioration Rate 被引量:2
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作者 Isiyaku Aliyu Babangida Sani 《American Journal of Operations Research》 2018年第1期1-16,共16页
In this present paper, an inventory model with a generalised exponential decreasing demand is considered. A numerical example is used to illustrate the application of the model. Sensitivity analysis of the optimal sol... In this present paper, an inventory model with a generalised exponential decreasing demand is considered. A numerical example is used to illustrate the application of the model. Sensitivity analysis of the optimal solution with respect to various parameters is carried out to see the effect of parameter changes on the solution. 展开更多
关键词 Linear deterioration Generalize EXPONENTIAL DECREASING DEMAND Inventory CONSTANT HOLDING Cost
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Serious Deterioration of Renal Function after Percutaneous Nephrolithotomy: A Case Report 被引量:1
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作者 Heng Zhang Houyong Zhou +2 位作者 Bo Song Zhansong Zhou Longkun Li 《Open Journal of Nephrology》 2011年第2期15-18,共4页
A 25-year-old man presented with stones in left kidney received the left Percutaneous nephrolithotomy (PCNL) with holmium laser lithotripsy. All the stones were successfully removed, and all the results were normal in... A 25-year-old man presented with stones in left kidney received the left Percutaneous nephrolithotomy (PCNL) with holmium laser lithotripsy. All the stones were successfully removed, and all the results were normal in the first three months followup. However, a deterioration of renal function was confirmed two years later. No mechanical obstruction was found with ureteroscopy. The deterioration of renal function may be induced by high internal renal pelvis pressure, injury of the laser energy, potential functional obstruction, and/or ischemia-reperfusion injury. 展开更多
关键词 PERCUTANEOUS NEPHROLITHOTOMY RENAL Function deterioration
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Simulation investigations on the marble deterioration by sulphur dioxide
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作者 Gan Weitang, Dai Shugui, Liu Youying, Liu Zhaomeng, Zhang Qingmin,Zhou Xingdi, Su Shengpei, Liu Xiao, Zhu RuiZhi,Fu Xueqi and R. J. ChengDepartment of Chemistry,Nankai University,Tianjin 300071,ChinaAtmospheric Science Ressarch Center,State University of New York,Albany,N.Y.12222,USA 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1991年第1期79-88,共10页
This paper deals with investigations on corrosion of marble SO2. We have simulated oxidation of SO2 by photochemical process in the atmosphere. The experiments indicate that formation of SO3 aerosols is related to the... This paper deals with investigations on corrosion of marble SO2. We have simulated oxidation of SO2 by photochemical process in the atmosphere. The experiments indicate that formation of SO3 aerosols is related to the concentration of SO2, the UV light intensity, the time of irradiation and the humidity of the air. The corrosion feature of surfaces of the marble and the depth profiles of sulphur were obtained by SEM (Scanning electron microscope), EDXA (Energy-dispersive X-ray analyzer) and SIMS (Secondary ion mass spectrometer). The results of experiments show the corrosive extent of marble depends on its compositions and microareas of marble, which contain lower silicon content can be easily corroded by SO2. 展开更多
关键词 acid RAIN ACIDIFICATION of environment PHOTOCHEMICAL process MARBLE deterioration SO2.
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Experimental Study on Surface Deterioration of Hot Rolling Mill Rolls under Near Service Conditions
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作者 Cui Peiyong 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 1996年第1期46-50,共5页
With specially designed hot rolling test equipment,the surface deterioration process of hot rolling mill rolls can be simulated and representative samples were obtained.Thus a series of micro-analyses can be done onto... With specially designed hot rolling test equipment,the surface deterioration process of hot rolling mill rolls can be simulated and representative samples were obtained.Thus a series of micro-analyses can be done onto the sample's worn surface,including wear loss,worn surface morphology,wear mode,oxidation and other influences from environment conditions.A leading study has been done with a high chromium cast iron to show the rolling test conditions and the methodologies of follow-up investigations for all the above-mentioned micro-analyses.Primary results have shown that high chromium iron roll may undergo complex degrading mechanism,and most of them can be investigated with the help of this research method- 展开更多
关键词 WEAR test SURFACE deterioration hot WEAR rolling MILL ROLL chromium iron
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Performance Deterioration Analysis of the Used Gear Oil 被引量:1
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作者 Qunfeng Zeng Guangneng Dong +1 位作者 Yanling Yang Tonghai Wu 《Advances in Chemical Engineering and Science》 2016年第2期67-75,共9页
In the present paper, we have investigated the tribological properties and microstructure of the used gear oil theoretically and experimentally. The deterioration process of the in-service gear lubricant oils was also... In the present paper, we have investigated the tribological properties and microstructure of the used gear oil theoretically and experimentally. The deterioration process of the in-service gear lubricant oils was also discussed. The viscosity and microstructure of oils running different mileages were analyzed by viscometer and Fourier Transform Infrared Spectroscopy (FTIR), respectively. In addition, the friction and wear behaviors of the friction pair of the GCr15 steel ball and disc were investigated using a ball on disc tribometer under different mileages’ gear oils lubrication conditions. These techniques give reproducible and reliable data with which to evaluate the severity of deterioration process of oils. The objective of this work is to understand the deterioration process of gear oil and analyze the influence of deterioration on the performance and microstructure of lubricant oils used in gear box. Possible explanations of deterioration process as well as its influence on friction and wear behaviors are also discussed. The results reveals the tribological properties of used oils depended on strongly the microstructure and its deterioration process of oil. 展开更多
关键词 Used Gear Oil Tribological Properties VISCOSITY FTIR deterioration
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THE MECHANISM OF SEED DETERIORATION
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作者 Liu Enju Feng Yulong Sun Hongzhi Northeast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1993年第1期6-10,共5页
Seed deterioration is an irresistible physiological phenomenon.The aim to studyseed deterioration is to see if seed deterioration can be retarded artificially and the higher seedvigor of fine varieties be maintained.T... Seed deterioration is an irresistible physiological phenomenon.The aim to studyseed deterioration is to see if seed deterioration can be retarded artificially and the higher seedvigor of fine varieties be maintained.The change of seed deterioration occurs in almost every sys-tem,and affects many kinds of enzyme and almost all organelle,as a result,the seed loses its vig-or.The reason of seed deterioration and the lost of seed vigor are mainly studied and discussed inthis paper.According to the external and internal two kinds of theory advanced by E.H.Roberts,Much deep discussions are made from the view of biochemistry. 展开更多
关键词 SEED deterioration deterioration Loses of VIGOR
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