A Method for Structuring Service Failure Factors to Realize Highly Reliable Services

As the society matures, customer requirements have become more varied. Services have been attracting increasing attention from industry and academic field as an effective mean to satisfy such varied customer requirements. In order to make a profit, it is important for companies to build and maintain long-term relationships with customers. Therefore, service providers should maintain their service quality and always satisfy their customers. To realize highly reliable product or services, in general, it is an effective approach to prevent failures from occurring in the use phase. Therefore, it is necessary that analysts identify the factors that could cause service failure and take appropriate measures against the target failure factor in advance. However, service failure factors are varied compared to physical products because service failures occur due to uncertainty elements such as human factors. In this study, we aim to enable service analysts to identify the critical failure factor from a number of failure factors. To achieve this, we identify complex failure factors and relationships among them from the viewpoint of the field where the service provided. This paper proposes a method for structuring the causal sequence between service failure factors by using a method of system modeling.

Factors of Failure of Community Interventions of PMTCT Activities in Haut Katanga in the Democratic Republic of Congo

The objective of the study was to identify the failure factors of community interventions in terms of HIV activities in the province of Haut-Katanga during the year 2016. Materials and Methods: The study was phenomenological of the factors, carried out in Haut Katanga. All health facilities (FOSAs) having integrated the prevention of transmission of HIV infection from mother to child (PMTCT) were included in the study. The collection was carried out through individual semi-structured interviews with PMTCT focal points, mentor mothers and people living with HIV (PLWHA) cared for in some of these health facilities (FOSAs). The number of participants was determined by the saturation of responses. Nvivo v.11 software was used for the analyses. The data of each woman was handled confidentially. The authorization of the ethics committee of the University of Kinshasa ESP/CE091/2015, the free and written consent, was obtained before collecting the information. Results: It was observed the socio-cultural factors of success and failure of the interventions: the social fear generated by contradictory messages in the sensitization of the community;the lack of an obvious strategy for the involvement of the partner;the weak coordination of community care activities between the central office of the health zone;the FOSA and the community worker: low interest in community care evidenced by weak accountability of FOSAs, community and program providers in this regard;that relates to community activities;coordination of care between care units;overload of the staff in charge of activities within the health structure and their low motivation;the low communication time devoted to people living with HIV in the FOSAs. Conclusion: The study shows that interventions that can improve the quality and outcomes of prevention of mother-to-child transmission of HIV (PMTCT) services can be directly linked to the program itself, as well as come from another or the community, which generally remains the weak link in which efforts are even less noticeable, at least as far as PMTCT is concerned. Integrating care data for the mother-child couple improve the continuum of services between the different care units as well as the quality of data management.

Study on the main factors that contribute to the success or failure of strategic alliances

Strategic alliance is an effective way for enterprise to realize its development and to enhance its competitiveness; however, the success rate of strategic alliances is less than fifty percent. According to this problem, this paper makes systematic research on the factors that relevant to the failure or success of strategic alliance based on comprehensive analysis on internal and external motivation for the formation of strategic alliance, the purpose of which is to give some references and supports for successfully constructing the strategic alliance.

A study of grid failure mode drivers and methods for accelerated life testing of a 30cm diameter ion thruster

In view of the high cost caused by the 1:1 lifetime verification test of ion thrusters,the lifetime acceleration test should be considered.This work uses the PIC-MCC(Particle-in-Cell MonteCarlo Collision)method to analyze the five failure factors that lead to the failure of the accelerator grid of a 30 cm diameter ion thruster under the working mode of 5 k W.Meanwhile,the acceleration stress levels corresponding to different failure factors are obtained.The results show that background pressure has the highest stress level on the grid's erosion.The accelerator grid aperture's mass sputtering rate under the rated vacuum degree(1×10^(-4)Pa)of 5 k W work mode is 8.78 times that of the baseline vacuum degree(1×10^(-6)Pa),and the mass sputtering rate under worse vacuum degree(5×10^(-3)Pa)is 5.08 times that of 1×10^(-4)Pa.Under the influence of the other four failure factors,namely,the voltage of the accelerator grid,upstream plasma density,the screen grid voltage and mass utilization efficiency,the mass sputtering rates of the accelerator grid hole are 2.32,2.67,1.98 and 2.51 times those of the accelerator grid hole under baseline condition,respectively.The ion sputtering results of two 30 cm diameter ion thrusters(both installed with new grids assembly)after working for 1000 h show that the mass sputtering rate of the accelerator grid hole under vacuum conditions of 5×10^(-3)Pa is 4.54 times that under the condition of 1×10^(-4)Pa,and the comparison error between simulation results and test results of acceleration stress is about 10%.In the subsequent ion thruster lifetime verification,the working vacuum degree can be adjusted according to the acceleration stress level of background pressure,so as to shorten the test time and reduce the test cost.

Failure characteristics of surface vertical wells for relieved coal gas and their influencing factors in Huainan mining area

Based on data from through-hole and logging,we studied the failure characteristics of surface drainage wells for relieved coal gas in Huainan mining area and its influencing factors.The results show that the damaged positions of drainage wells are mainly located at the thick clay layer in the low alluvium and the lithological interface in the upper section of bedrock in west mining area.The failure depth of casing is 244-670 m and concentrates at about 270-460 m deep.These damaged positions are mainly located in the bending zone according to three zones of rock layers in the vertical section above the roof divided. Generally,the casing begins to deform or damage before the face line about 30-150 m.Special formation structure and rock mass properties are the direct causes of the casing failure,high mining height and fast advancing speed are fundamental reasons for rock mass damage.However,the borehole configuration and spacing to the casing failure are not very clear.

Analyzing risk factors for postoperative acute renal failure requiring dialysis after valve surgery

Objective To evaluate risk factors for postoperative acute renal failure requiring dialysis (ARF-D) after hear valve surgery. Methods Adult patients (age≤18 years) underwent valve surgery with preoperative serum creati nine 【 300 μmol / L were included between January 2005 and December 2008. Fifty patients developed ARF-D

THE NEW CRITERIA OF ELASTIC AND FATIGUE FAILURE IN THE COMPONENT OF COMPLEX STRESS STATES

In this paper, a total criterion on elastic and fatigue failure in complex stress, that is. octahedral stress strength theory on dynamic and static states on the basis of studying modern and classic strength theories. At the same time, an analysis of an independent and fairly comprehensive theoretical system is set up. It gives generalized failure factor by 36 materials and computative theory of the 11 states of complex stresses on a point, and derives the operator equation on generalized allowable strength and a computative method for a total equation can be applied to dynamic and static states. It is illustrated that the method has a good exactness through computation of eight examples of engineering. Therefore, the author suggests applying it to engineering widely.

Energy analysis of stability on shallow tunnels based on non-associated flow rule and non-linear failure criterion

On the basis of upper bound theorem, non-associated flow rule and non-linear failure criterion were considered together.The modified shear strength parameters of materials were obtained with the help of the tangent method. Employing the virtual power principle and strength reduction technique, the effects of dilatancy of materials, non-linear failure criterion, pore water pressure,surface loads and buried depth, on the stability of shallow tunnel were studied. In order to validate the effectiveness of the proposed approach, the solutions in the present work agree well with the existing results when the non-associated flow rule is reduced to the associated flow rule and the non-linear failure criterion is degenerated to the linear failure criterion. Compared with dilatancy of materials, the non-linear failure criterion exerts greater impact on the stability of shallow tunnels. The safety factor of shallow tunnels decreases and the failure surface expands outward when the dilatancy coefficient decreases. While the increase of nonlinear coefficient, the pore water pressure coefficient, the surface load and the buried depth results in the small safety factor. Therefore, the dilatancy as well as non-linear failure criterion should be taken into account in the design of shallow tunnel supporting structure. The supporting structure must be reinforced promptly to prevent potential mud from gushing or collapse accident in the areas with abundant pore water, large surface load or buried depth.

Adult-to-adult living donor liver transplantation for acute liver failure in China

AIM:To investigate the long-term outcome of recipients and donors of adult-to-adult living-donor liver transplantation(AALDLT) for acute liver failure(ALF).METHODS:Between January 2005 and March 2010,170 living donor liver transplantations were performed at West China Hospital of Sichuan University.All living liver donor was voluntary and provided informed consent.Twenty ALF patients underwent AALDLT for rapid deterioration of liver function.ALF was defined based on the criteria of the American Association for the Study of Liver Diseases,including evidence of coagulation abnormality [international normalized ratio(INR) ≥ 1.5] and degree of mental alteration without pre-ex-isting cirrhosis and with an illness of < 26 wk duration.We reviewed the clinical indications,operative procedure and prognosis of AALDTL performed on patients with ALF and corresponding living donors.The potential factors of recipient with ALF and corresponding donor outcome were respectively investigated using multivariate analysis.Survival rates after operation were analyzed using the Kaplan-Meier method.Receiver operator characteristic(ROC) curve analysis was undertaken to identify the threshold of potential risk factors.RESULTS:The causes of ALF were hepatitis B(n = 18),drug-induced(n = 1) and indeterminate(n = 1).The score of the model for end-stage liver disease was 37.1 ± 8.6,and the waiting duration of recipients was 5 ± 4 d.The graft types included right lobe(n = 17) and dual graft(n = 3).The mean graft weight was 623.3 ± 111.3 g,which corresponded to graft-torecipient weight ratio of 0.95% ± 0.14%.The segment Ⅴor Ⅷ hepatic vein was reconstructed in 11 right-lobe grafts.The 1-year and 3-year recipient's survival and graft survival rates were 65%(13 of 20).Postoperative results of total bilirubin,INR and creatinine showed obvious improvements in the survived patients.However,the creatinine level of the deaths was increased postoperatively and became more aggravated compared with the level of the survived recipients.Multivariate analysis showed that waiting duration was independently correlated with increased mortality(P = 0.014).Furthermore,ROC curve revealed the cut-off value of waiting time was 5 d(P = 0.011,area under the curve = 0.791) for determining the mortality.The short-term creatinine level with different recipient's waiting duration was described.The recipients with waiting duration ≥ 5 d showed the worse renal function and higher mortality than those with waiting duration < 5 d(66.7% vs 9.1%,P = 0.017).In addition,all donors had no residual morbidity.Furthermore,univariate analysis did not show that short assessment time induced the high morbidity(P = 0.573).CONCLUSION:Timely AALDLT for patients with ALF greatly improves the recipient survival.However,further systemic review is needed to investigate the optimal treatment strategy for ALF.

Serum granulocyte colony-stimulating factor in patients with chronic renal failure

Objective To gain a better understanding of the regulatory mechanism and kinetic behaviour of granulocyte colony-stimulating factor (G-CSF).Methods An enzyme-linked immunosorbent assay (ELISA) method was used to detect serum G-CSF in 61 patients with chronic renal failure±long-term hemodialysis and 30 normal controls. Results Serum G-CSF levels in CRF patients were significantly higher than in normal controls. Eighty percent of patients had detectable G-CSF and serum G-CSF levels were 566.40±207.98?ng/L in non-hemodialyzed (non-HD) patients. The detectable percentage in hemodialyzed patients was 93.33%, serum G-CSF levels in pre-HD and post-HD patients were 1255.36±611.25?ng/L and 1151.61±599.47?ng/L respectively. Serum G-CSF levels in HD patients were slightly higher than in non-HD patients, but no significant difference was found between the two groups. No difference was found between the G-CSF values obtained in pre-HD and post-HD patients. There was no relationship between G-CSF levels and WBC, BUN or Scr (P>0.05).Conclusion The high value of G-CSF in patients with CRF may be caused by a decrease in G-CSF clearance and/or an increase in G-CSF release.

Determination and stability analysis of ultimate open-pit slope under geomechanical uncertainty

In open-pit mines,pit slope as one of the important parameters affects the mine economy and total minable reserve,and it is also affected by different uncertainties which arising from many sources.One of the most critical sources of uncertainty effects on the pit slope design is rock mass geomechanical properties.By comparing the probability of failure resulted from deterministic procedure and probabilistic one,this paper investigated the effects of aforesaid uncertainties on open-pit slope stability in metal mines.In this way,to reduce the effect of variance,it implemented Latin Hypercube Sampling(LHS)technique.Furthermore,a hypothesis test was exerted to compare the effects on two cases in Middle East.Subsequently,the investigation approved high influence of geomechanical uncertainties on overall pit steepness and stability in both iron and copper mines,though on the first case the effects were just over.

Research on the stability analysis and design of soil tunnel surrounding rock

The paper first analyzes the failure mechanism and mode of tunnel according to model experiments and mechanical calculation and then discusses the deficiency of taking the limit value of displacement around the tunnel and the size of the plastic zone of surrounding rock as the criterion of stability. So the writers put forward the idea that the safety factor of surrounding rock calculated through strength reduction FEM(finit element method) should be regarded as the criterion of stability,which has strict mechanical basis and unified standard and would not be influenced by other factors. The paper also studies the safety factors of tunnel surrounding rock (safety factors of shear and tension failure) and lining and some methods of designing and calculating tunnels. At last,the writers take the loess tunnel for instance and show the design and calculation results of two-lane railway tunnel.

Advanced Unified Failure Model on Uniformly Reinforced Concrete Box Section Members

Based on the traditional Nielsen model,a unified failure model on the uniformly reinforced concrete box section members under combined forces was introduced by Luo and Liu.One of their contributions is adjustment of the shear carrying capacity of concrete at the member failure surface.In the unified failure model,the comparison with the experimental results verified this adjustment.Nevertheless,it should be pointed out that the adjustment factor of shear carrying capacity at member failure surface for the reinforced concrete members in the unified failure model is a fixed adjustment constant for all experiment data,which is basically determined by curve fitting.However,the adjustment factor should vary with the normal stress at the member failure surface.In this paper,an advanced theoretical model is introduced,in which the adjustment factor of shear carrying capacity at failure surface is a variable related to the normal stress at failure surface.Furthermore,the advanced unified failure model on the uniformly reinforced concrete box section member can still be expressed in a simple form.Finally,the comparison with several groups of test data has verified that this advanced model is more accurate and feasible to be used in design.