• Title/Summary/Keyword: failure stage

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Comparison of the Walz Nomogram and Presence of Secondary Circulating Prostate Cells for Predicting Early Biochemical Failure after Radical Prostatectomy for Prostate Cancer in Chilean Men

  • Murray, Nigel P;Reyes, Eduardo;Orellana, Nelson;Fuentealba, Cynthia;Jacob, Omar
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.16
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    • pp.7123-7127
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    • 2015
  • Purpose: To determine the utility of secondary circulating prostate cells for predicting early biochemical failure after radical prostatectomy for prostate cancer and compare the results with the Walz nomagram. Materials and Methods: A single centre, prospective study of men with prostate cancer treated with radical prostatectomy between 2004 and 2014 was conducted, with registration of clinical-pathological details, total serum PSA pre-surgery, Gleason score, extracapsular extension, positive surgical margins, infiltration of lymph nodes, seminal vesicles and pathological stage. Secondary circulating prostate cells were obtained using differential gel centrifugation and assessed using standard immunocytochemistry with anti-PSA. Biochemical failure was defined as a PSA >0.2ng/ml, predictive values werecalculated using the Walz nomagram and CPC detection. Results: A total of 326 men participated, with a median follow up of 5 years; 64 had biochemical failure within two years. Extracapsular extension, positive surgical margins, pathological stage, Gleason score ${\geq}8$, infiltration of seminal vesicles and lymph nodes were all associated with higher risk of biochemical failure. The discriminative value for the nomogram and circulating prostate cells was high (AUC >0.80), predictive values were higher for circulating prostate cell detection, with a negative predictive value of 99%, sensitivity of 96% and specificity of 75%. Conclusions: The nomagram had good predictive power to identify men with a high risk of biochemical failure within two years. The presence of circulating prostate cells had the same predictive power, with a higher sensitivity and negative predictive value. The presence of secondary circulating prostate cells identifies a group of men with a high risk of early biochemical failure. Those negative for secondary CPCs have a very low risk of early biochemical failure.

An Exploratory Research for the Conceptualization Failure knowledge (실패지식의 개념화를 위한 탐색적 연구)

  • Shim, Hyungseok
    • Knowledge Management Research
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    • v.12 no.4
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    • pp.121-132
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    • 2011
  • Failure, the research object, means situations when goals and their results are different, which has developed presenting various aspects from ancient times and modern times. Failure is a complex concept which essentially requires judgement, and also a relative concept which can be changed depending on how you set up time base and standard. There are four stages for failure study to have been developed from studying failure through historical facts to the approach of organizational theory and it has been studied by looking at the failure of an organization according to different categories such as a developmental stage, a type of business, a period and a course. Compared with success science, failure study has not been studied sufficiently and also the level of its analysis is low. Thus, since lessons of failure tend to repeat themselves instead of being didactically accumulated, there need more studies on this. This thesis identified the main cause of the failure through various studies regarding failure which have been conducted at home and abroad. What the main cause of the failure that more than three studies mentioned have in common was that it occurred because organizations concentrated on the inside without communicating with external environment. The key point of failure study is to analyze failure, utilize it as assets, and create a frame of failure management. This thesis focused on delivering fragmentary knowledge on failure study, but case studies regarding this subject should be done in the future.

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The Result and Failure after Adjuvant Postoperative Irradiation in Carcinoma of Recum (직장암의 방사선 치료결과 및 실패양상)

  • Kim Chul-Yong;Choi Myung-Sun
    • Radiation Oncology Journal
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    • v.11 no.1
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    • pp.133-141
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    • 1993
  • From Jan.1982 to Dec.1990, 77 patients with rectal cancer were treated with curative surgical resection followed by postoperative adjuvant irradiation alone or combined with chemotherapy at the Department of Radiation Oncology, Korea University Hospital (KUH). Fifty-four (54/77, $70.1{\%}$) patients underwent abdominoperineal resection , 20 (20/77, $26{\%}$) patients underwent low anterior resection, and 3 (3/77, $3.9{\%}$,) patients had wide excision only. Thirty-nine (39/77, $50.5{\%}$) received sequential chemotherapy (2 cycles to 12 cycles). The 5-year survival rate for the entire group was $43{\%}:\;78.2{\%}$ in B2+B3, $39.4{\%}$ in stage C1+C2+C3. Survival rates decreased with increasing penetration of the bowel wall by tumor and the presence of regional lymph node metastasis. Those patients survival who underwent an abdominoperineal resection also experienced a significant decrease in compared to low anterior resection ($23.1{\%}$ vs. $63.8{\%}$ in 5-year survival, p <0.05). Local failure occurred in 15 ($19.5{\%}$) out of the 77 patients overall, 1($5.3{\%}$) of 19 in stage B2+B3, and 14 ($24.1{\%}$,) of 58 in stage C1+C2+C3. Presacral area was most common site of local failufre (8/17, $47.1{\%}$). Distant failure occurred in 13 ($16.9{\%}$) of 77 patients. The most frequent site of distant failure was the lung followed by the liver, the bone, and the brain. Combined locoregional and distant failure occurred in 2 ($2.6{\%}$) of 77 patients. Pathological confirmation of perirectal fat and/or regional lymph node involvement resulted in a singificant decrease in survival and local control.

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Plasmaphresis therapy for pulmonary hemorrhage in a pediatric patient with IgA nephropathy

  • Yim, Dae-Kyoon;Lee, Sang-Taek;Cho, Heeyeon
    • Clinical and Experimental Pediatrics
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    • v.58 no.10
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    • pp.402-405
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    • 2015
  • IgA nephropathy usually presents as asymptomatic microscopic hematuria or proteinuria or episodic gross hematuria after upper respiratory infection. It is an uncommon cause of end-stage renal failure in childhood. Pulmonary hemorrhage associated with IgA nephropathy is an unusual life-threatening manifestation in pediatric patients and is usually treated with aggressive immunosuppression. Pulmonary hemorrhage and renal failure usually occur concurrently, and the pulmonary manifestation is believed to be caused by the same immune process. We present the case of a 14-year-old patient with IgA nephropathy who had already progressed to end-stage renal failure in spite of immunosuppression and presented with pulmonary hemorrhage during oral prednisone treatment. His lung disease was comparable to diffuse alveolar hemorrhage and was successfully treated with plasmapheresis followed by oral prednisone. This case suggests that pulmonary hemorrhage may develop independently of renal manifestation, and that plasmapheresis should be considered as adjunctive therapy to immunosuppressive medication for treating IgA nephropathy with pulmonary hemorrhage.

Reliability test design for Electric and movement apparatus of recliner sofa for home use (가정용 리클라이너 소파의 전기 및 기구부에 대한 신뢰성시험 설계)

  • Jang, In-Hyeok;Hyung, Jae-pil;Lim, Hong-Woo;Choi, Youn-Ok
    • Journal of Advanced Engineering and Technology
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    • v.11 no.4
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    • pp.259-265
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    • 2018
  • In this paper, we propose a test method to evaluate the reliability of the recliner sofa in the early stage of production. In order to develop the test method, we analyzed the failure mechanism occurring in the field and designed the performance test, environmental test, accelerated life test methods based on the analysis of failure mechanism. The failure mechanism is reproduced by applying the designed test. The reliability of the recliner sofa can be verified at the production stage through the proposed test method.

Experimentally evaluating the seismic retrofitting of square engineered cementitious composite columns using CFRP

  • Akhtari, Alireza;Mortezaei, Alireza;Hemmati, Ali
    • Structural Engineering and Mechanics
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    • v.78 no.5
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    • pp.545-556
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    • 2021
  • The present experimental study evaluated the seismic performance of six engineered cementitious composite (ECC) columns strengthened with carbon fiber reinforced polymer (CFRP) laminates under cyclic lateral loading. The ECC columns damaged and crushed in the first stage of cyclic tests were repaired using the ECC with a certain polyvinyl alcohol (PVA) fiber and strengthened with flexural and sheer CFRP laminates and then re-assessed under the cyclic loading. The effects of some variables were examined on lateral displacement, energy absorption and dissipation, failure modes, crack patterns, load bearing capacity and plasticity, and the obtained results were compared with those of the first stage of cyclic tests. The results showed that retrofitting the ECC columns can improve their performance, plasticity and load-bearing threshold, delayed the concrete failure, changed the failure modes and increased the energy absorbed by the strengthened columns element by over 50%.

Experimental and analytical assessment of SRF and aramid composites in retrofitting RC columns

  • Dang, Hoang V.;Shin, Myoungsu;Han, Sang Whan;Lee, Kihak
    • Earthquakes and Structures
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    • v.7 no.5
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    • pp.797-815
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    • 2014
  • This research aimed to investigate retrofitting methods for damaged RC columns with SRF (Super Reinforced with Flexibility) and aramid composites and their impacts on the seismic responses. In the first stage, two original (undamaged) column specimens, designed to have a flexural- or shear-controlled failure mechanism, were tested under quasi-static lateral cyclic and constant axial loads to failure. Afterwards, the damaged column specimens were retrofitted, utilizing SRF composites and aramid rods for the flexural-controlled specimen and only SRF composites for the shear-controlled specimen. In the second stage, the retrofitted column specimens were tested again under the same conditions as the first stage. The hysteretic responses such as strength, ductility and energy dissipation were discussed and compared to clarify the specific effects of each retrofitting material on the seismic performances. Generally, SRF composites contributed greatly to the ductility of the specimens, especially for the shear-controlled specimen before retrofitting, in which twice the deformation capacity was obtained in the retrofitted specimen. The shear-controlled specimen also experienced a flexural failure mechanism after retrofitting. In addition, aramid rods moderately fortified the specimen in terms of the maximum shear strength. The maximum strength of the aramid-retrofitted specimen was 12% higher than the specimen without aramid rods. In addition, an analytical modeling of the undamaged specimens was conducted using Response-2000 and Zeus Nonlinear in order to further validate the experimental results.

Multi-stage Analysis of Elliptic Cup Drawing Processes with the Large Aspect Ratio by an Explicit Elasto-Plastic Finite Element Method (외연적 유한요소법을 이용한 세장비가 큰 타원형 컵 성형공정의 다단계 해석)

  • Kim, S.H.;Kim, S.H.;Huh, H.
    • Transactions of Materials Processing
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    • v.9 no.3
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    • pp.313-319
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    • 2000
  • Finite element analysis is carried out for simulation of the multi-stage elliptic cup drawing process with the large aspect ratio. The analysis incorporates with shell elements for an elasto-plastic finite element method with the explicit time integration scheme. For the simulation, LS-DYNA3D is utilized for its wide capability of solving forming problems. The simulation result shows that the non-uniform drawing ratio at the elliptic cross section ad the small shoulder radius cause failure such as tearing and wrinkling. The result suggests the guideline to modify the tool shape for prevention of the failure during the drawing process.

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Comparison of Hoek-Brown and Mohr-Coulomb failure criterion for deep open coal mine slope stability

  • Aksoy, Cemalettin O.;Uyar, Guzin G.;Ozcelik, Yilmaz
    • Structural Engineering and Mechanics
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    • v.60 no.5
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    • pp.809-828
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    • 2016
  • In deep open pit mines, slope stability is very important. Particularly, increasing the depths increase the risks in mines having weak rock mass. Blasting operations in this type of open pits may have a negative impact on slope stability. Several or combination of methods can be used in order to enable better analysis in this type of deep open-pit mines. Numerical modeling is one of these options. Many complex problems can be integrated into numerical methods at the same time and analysis, solutions can be performed on a single model. Rock failure criterions and rock models are used in numerical modeling. Hoek-Brown and Mohr-Coulomb terms are the two most commonly used rock failure conditions. In this study, mine planning and discontinuity conditions of a lignite mine facing two big landslides previously, has been investigated. Moreover, the presence of some damage before starting the study was identified in surrounding structures. The primary research of this study is on slope study. In slope stability analysis, numerical modeling methods with Hoek-Brown and Mohr-Coulomb failure criterions were used separately. Preparing the input data to the numerical model, the outcomes of patented-blast vibration minimization method, developed by co-author was used. The analysis showed that, the model prepared by applying Hoek-Brown failure criterion, failed in the stage of 10. However, the model prepared by using Mohr-Coulomb failure criterion did not fail even in the stage 17. Examining the full research field, there has been ongoing production in this mine without any failure and damage to surface structures.

Dilatation characteristics of the coals with outburst proneness under cyclic loading conditions and the relevant applications

  • Li, Yangyang;Zhang, Shichuan;Zhang, Baoliang
    • Geomechanics and Engineering
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    • v.14 no.5
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    • pp.459-466
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    • 2018
  • By conducting uniaxial loading cycle tests on the coal rock with outburst proneness, the dilatation characteristics at different loading rates were investigated. Under uniaxial loading and unloading, the lateral deformation of coal rock increased obviously before failure, leading to coal dilatation. Moreover, the post-unloading recovery of the lateral deformation was rather small, suggesting the onset of an accelerated failure. As the loading rate increased further, the ratio of the stress at the dilatation critical point to peak-intensity increased gradually, and the pre-peak volumetric deformation decreased with more severe post-peak damage. Based on the laboratory test results, the lateral deformation of the coals at different depths in the #1302 isolated coal pillars, Yangcheng Coal Mine, was monitored using wall rock displacement meter. The field monitoring result indicates that the coal lateral displacement went through various distinct stages: the lateral displacement of the coals at the depth of 2-6 m went through an "initial increase-stabilize-step up-plateau" series. When the coal wall of the working face was 24-18 m away from the measuring point, the coals in this region entered the accelerated failure stage; as the working face continued advancing, the lateral displacement of the coals at the depth over 6 m increased steadily, i.e., the coals in this region were in the stable failure stage.