Predictive Criteria Research Articles

Predicting Consumption Intention of Consumer Relationship Management Users Using Deep Learning Techniques: A Review

Consumer/customer relationship management (CRM) can potentially influence business as it predicts changes in people’s perspectives, which could impact future sales. Accordingly, advancements in Information Technology are under investigation to see their capabilities to improve the work of CRM. Many prediction techniques, such as Data Mining, Machine Learning (ML), and Deep Learning (DL), were found to be utilized with CRM. ML methods were found to dominate other approaches in terms of the prediction of consumers’ intention to purchase. This review provides DL algorithms that are mostly used in the last five years, to support CRM to predict purchase intention for better product sales decisions. Prediction criteria related to online activities and behavior were found to be the most inputs of prediction models. DL approaches are slowly applied within purchase intention prediction due to their advanced capabilities in handling large and complicated datasets with minimum human supervision. DL models such as CNN and LSTM result in high accuracy in prediction intention with 98%. Future research uses the two algorithms (CNN, LSTM) compiled to make the best prediction consumption in CRM. Additionally, an effort is being made to create a framework for predicting purchases based on many DL algorithms and the most pertinent characteristics.

Study on rainfall early warning model for Xiangmi Lake slope based on unsaturated soil mechanics

Abstract Urban expansion caused numerous geological hazards, particularly in the mountainous areas. In this article, the unsaturated soil mechanics combined with a numerical method is applied to build the rainfall thresholds for the Xiangmi Lake slope in early warning. The drainage mechanism in soil slope under different rainfall conditions has been studied. Then, the actual rainfall data collected in the rainy season are taken as the rainfall condition to simulate the actual rainfall situation. The corresponding safety factor of the slope under the rainfall has been calculated and compared with the improved deformation tangential angle criterion for the slope safety prediction. The tangent angle can be used as the judgment basis to classify the early warning levels of a rainstorm, which helps to establish the early warning model of slope rainfall and guide the landslide early warning.

The level of acute phase blood proteins as a predictive criterion of the cryo resistance of stallion sperm

The indicators of the biochemical analysis of the blood of horses reflect the state of metabolism of the animal and at the same time are potential predictors of the qualitative characteristics of spermatozoa, the freezing of which is one of the most important ways to preserve and further use the genetic material. The aim of this study was to identify correlations between the level of such acute phase blood proteins, as C-reactive protein and fibrinogen, and the qualitative and quantitative characteristics of the native and thawed sperm of stallions. The object of the study was blood and sperm samples from 87 stallions of various breeds, the average age of which was 10.5±0.5 years. To assess the protein status of the blood, in addition to the aforementioned acute phase proteins, the total protein content, the levels of albumin, globulins, and the albumin / globulin ratio were determined. Stallion sperm samples were assessed according to the following indicators: ejaculate volume, concentration, the total number of spermatozoa in the ejaculate, progressive motility and survival at +4°C. When analyzing the correlations between the studied parameters, a statistically significant negative inverse relationship was revealed between the level of fibrinogen in the blood serum and such parameters as the content of progressively motile sperm in native and thawed cryopreserved sperm (r=-0.22, p<0.05 and r=-0.29, p<0.01, respectively), as well as sperm survival in native and thawed sperm (r=-0.48, p<0.001 and r=-0.22, p<0.05, respectively).There was no statistically significant relationship between the level of C-reactive protein and the studied characteristics of the spermogram. The revealed negative correlation between the level of fibrinogen and the characteristics of the stallions’ sperm can be considered as one of the prognostic important indicators that must be taken into account when selecting stallions with the highest indicators of the quality of cryopreserved sperm.

Fertility Outcomes after Surgical Management of Colorectal Endometriosis: A Single-center Retrospective Study

To assess the pregnancy rate after surgery for colorectal endometriosis. A retrospective, single-centre study performed from January 2014 to December 2019. A university tertiary referral centre. Patients with the intention to get pregnant under the age of 43 years, with or without a history of infertility and who were surgically managed for colorectal endometriosis. Complete excision of deeply infiltrating endometriosis (DIE). The postoperative pregnancy rate was assessed. Seventy-seven patients had surgery; their mean age was 32.5 ± 4.4 years. Preoperative documented infertility was present in 77.9% (n = 60) of patients. The mean length of history of infertility was 36.2 ± 24.9 months. The procedure was performed by laparoscopic surgery in 92.2% (n = 71) of patients. Non-conservative, conservative and mixed treatment were performed in 66.2% (n = 51), 29.9% (n = 23) and 3.9% (n = 3) of patients, respectively. According to the Clavien-Dindo classification, the 3B complication rate was 6.5% (n = 5). The mean follow-up was 46.7 ± 20.6 months. Clinical pregnancies were defined by the presence of intra-uterine pregnancy with an embryo with cardiac activity. The postoperative pregnancy rate was 62.3% (n = 48), and 54.2% (n = 26) were spontaneous. The mean number of pregnancies was 1.2 ± 0.4 per patient. In addition, 18.7% (n = 9) of patients got pregnant twice. The mean time from surgery to pregnancy was 13.8 ± 13.1 months. The live birth rate was 89.1% (n = 41). There were no significant differences concerning the prognostic criteria reported in the literature (anti-Müllerian hormone level, age, presence of adenomyosis). There were no predictive criteria for live births. According to this study, surgery for colorectal endometriosis results in a high postoperative pregnancy rate. Studies with a high level of evidence are needed to determine good candidates for this type of surgery.

Added value of multiple autoantibody testing for predicting progression to inflammatory arthritis in at-risk individuals

BackgroundPredicting progression to clinical arthritis in individuals at-risk of developing rheumatoid arthritis is a prerequisite to developing stratification groups for prevention strategies. Selecting accurate predictive criteria is the critical step...

Identifying and ranking components of manufacturing sustainability in the Iranian papermaking industry

Factors of manufacturing sustainability in the papermaking industry were identified and ranked using qualitative analysis and nonparametric tests. Based on a review of the literature on sustainable development and production, seven main factors of economic, environmental, technological, social, human, material and product, and regulations were identified to underpin the manufacturing sustainability in the papermaking industry, as well as some sub-factors. Then, a self-designed questionnaire was developed to take a poll among papermaking managers and experts regarding the effectiveness of the factors and sub-factors in manufacturing sustainability and their status. The factors affecting manufacturing sustainability in the papermaking industry were confirmed by the standard and significance coefficients in the structural equations and the predictive criterion. The cross-validated redundancy index showed that the data were valid enough for prediction. The research factors were ranked by the ordinal average affecting sustainability, current status, and distance to sustainability. The materials and product, environmental, technological, and economic factors had the greatest influence on manufacturing sustainability, and the regulation and human factors had the highest distance to sustainability. To achieve manufacturing sustainability in the papermaking industry, regulations and human factors need to be further studied. Their improvement has potential to achieve manufacturing sustainability.

Clonal Hematopoiesis Detected at the Time of Tyrosine Kinase Inhibitor Cessation Is Associated with Delayed Molecular Recurrence after Treatment-Free Remission in Patients with CML

Background Treatment-free remission (TFR) is a goal of therapy. However, ~50% of patients who attempt TFR will relapse, which mostly occurs by 6 months. The acquisition of somatic mutations in hematopoietic cells is common with age (clonal hematopoiesis, CH). Through next-generation sequencing studies we identified CH in patients in deep molecular remission. CH variants provide a selective growth advantage to cells, driving their clonal expansion. The clones also give rise to mutated immune effector cells with a proinflammatory profile that exacerbate diseases with a chronic inflammatory component, such as atherosclerosis. CH variants could potentially influence TFR, either by outcompeting an emerging residual CML clone or by altering immune function, which is known to play an important role in TFR. Aim To determine whether CH variants present at the time of therapy cessation could influence TFR. Methods An RNA-based hybridization capture sequencing method targeting 17 of the most frequently mutated CH genes was developed and applied to samples of 138 patients who attempted TFR. CH variants met strict criteria for pathogenicity based on their potential to confer growth and survival advantages. The CH status was confirmed by repeat testing of samples of 28 patients. The method reproducibly detected variants with a variant allele frequency (VAF) of ≥0.4%. Results The median follow-up for the 138 patients was 66 months from the TFR attempt. Molecular recurrence was defined as loss of major molecular response (MMR, BCR::ABL1 ≤0.1%). The probability of TFR was 64.5% at 6 months, 59.4% at 12 months and 51.0% at 84 months. CH variants were detected in 61/138 patients (44%): 107 variants in 12 genes. Multiple variants, range 2 - 7, were detected in 26 patients (19%). The median VAF was 0.9%, range 0.4 - 44%. Variants most frequently occurred in TET2 (44% of variants), DNMT3A (25%), PPM1D (7.4%) and ASXL1 (6.5%). The average age at cessation was 59.6 years, range 33 - 85. The average age of patients with CH was higher than those without CH: 64.7 versus 55.5 years, P < .0001. Only 3/13 patients (15%) aged ≤40 had CH compared with 6/7 patients (86%) ≥80. CH was significantly associated with TFR to 36 months after cessation. The optimal criteria for TFR prediction were at least one CH variant of VAF >2% or >2 variants (CH >2%/>2). Thirty-one of 138 patients (22%) had CH of VAF >2% (n = 24) or >2 variants (n = 7). The probability of TFR for these 31 patients was significantly higher than for the remaining patients when assessed at 6, 12, 24 and 36 months after cessation, Figure. The probability of TFR at 6 months was 90.3% for patients with CH >2%/>2 versus 57.0% for the remaining patients, P = .001. The probability of TFR at 36 months was 65.9% versus 51.2%, P = .049. A landmark analysis was performed at 12 months for the 74 patients who maintained TFR at 12 months. MMR was subsequently lost in 8/74 patients and the probability of TFR at 84 months was 86.9%. CH >2%/>2 occurred for 23/74 patients (31%). The probability of late molecular recurrence was higher among the patients with CH >2%/>2: 27.3% versus 5.5% for the remaining patients, P = .009. Overall, molecular recurrence occurred for 12/31 patients (39%) with CH >2%/>2 and 53/107 of remaining patients (50%). Time to molecular recurrence after cessation was longer for patients with CH >2%/>2 than the remaining patients: median 12.5 months versus 3.5 months, P < .0001. The longer time to molecular recurrence was linked to a different pattern of loss of MMR. The median time between first loss of MR4 (BCR::ABL1 ≤0.01%) and loss of MMR was 145 days for patients with CH >2%/>2 and 28 days for remaining patients, P = .0007. BCR::ABL1 values more frequently fluctuated before loss of MMR in patients with CH >2%/>2: 8/12 patients (67%, fluctuation over 120-1335 days) versus 6/53 (11%, fluctuation over 85-715 days) in the remaining patients, P =.016. Conclusion CH may improve the probability and duration of TFR, delaying the time to molecular recurrence, which has implications for patient selection and monitoring. Patients with CH who are eligible for therapy cessation have an excellent prospect of remaining drug-free for 1-2 years but their long term prospects of sustained TFR may be less certain compared to other patients, given the slower dynamics of relapse. Delayed relapse could be due to competition for clonal dominance between residual leukemic cells and larger CH clones, or modulation of the immune microenvironment. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Clinical and immunological criteria for prediction of thechronic course of cytomegalovirus infection on the background of hypoxic-ischemic damage of the central nervous system in children in the first year of life

Objective. To develop prognostic criteria for the chronic course of cytomegalovirus infection by studying disorders of the regulation of the immune response in children of the first year of life against the background of hypoxic-ischemic CNS damage.Materials and methods. 108 newborns with cytomegalovirus infection occurring against the background of perinatal hypoxicischemic lesions of the central unequal system were examined. All observed patients at 1 and 3 months of life conducted an immunological examination, including the determination of T and B-lymphocytes. Determination of the population and subpopulation composition of peripheral blood lymphocytes, activation markers was carried out by the method of one- and twoparameter phenotyping using reagents from Immunotex (France), FITC (fluorescein isothiocynate) — labeled with CD3+, CD4+, CD8+, CD20+ and PE (phycoerythrin) — labeled CD28+, CD40+. The results were recorded on a BECKMAN COULTER EPICSXL-II flow cytometer (USA) using standard protocols. The observation groups consisted of 78 children (72.2%) with an acute course of the disease (Group 1) and 30 children (27.3%) with a chronic course (Group 2).Results. Of the totality of the studied parameters of the cellular and humoral parts of the immune system, statistically significant for the prognosis of the chronic course of cytomegalovirus infection in children of the first year of life against the background of hypoxic-ischemic CNS damage were found: CD8, CD40, CD3+CD28+, CD20+CD40+. Using the PolyAnalist 3.5 Pro CNS package, systems of inequalities were obtained and a formula for predicting the chronic course of cytomegalovirus infection in children in the first year against the background of perinatal hypoxic-ischemic CNS damage was calculated.Conclusion. A statistically significant relationship was found between the prognosis of the chronic course of cytomegalovirus infection against the background of perinatal hypoxic-ischemic CNS damage and the level of CD20, CD4, costimulatory molecules CD3+CD28–, CD20+CD40+. The proposed diagnostic rules can be considered screening markers for the prognosis of the chronic course of cytomegalovirus infection against the background of perinatal hypoxic-ischemic CNS damage in newborns, which makes it possible to start specific therapy in a timely manner.

Characteristics of lung metastasis in testicular cancer: A large-scale population analysis based on propensity score matching.

This study aims to systematically evaluate predictive factors for lung metastasis (LM) in patients with testicular cancer (TC) and to investigate cancer-specific survival (CSS) and overall survival (OS) of LM in TC patients based on a large population-cohort. A total of 10,414 patients diagnosed with TC during 2010-2015 were adopted from the Surveillance, Epidemiology, and End Results (SEER). After propensity score matching (PSM), 493 patients with LM were included for subsequent analysis. Univariate and multivariate logistic regression analyses were employed to identify risk factors, a nomogram was developed, and the receiver operating characteristic (ROC) curve was utilized to confirm the validation of the nomogram. Prognostic factors for OS and CSS among TC patients with LM were estimated via Cox proportional hazards models. Postmatching indicated that 11 parameters were successfully balanced between both groups (P > 0.05). After PSM, TC patients with LM presented an undesirable prognosis in both CSS and OS than those without LM (P < 0.001). The logistic regression model showed that tumor size; T stage; N stage; liver, brain, and bone metastases; and histology were positively associated with LM (P < 0.05). A nomogram was developed to predict diagnostic possibilities based on the independent risk variables, and the ROC curve verified the predictive capacity of the logistic regression model [area under the curve (AUC) = 0.910]. The selected variates in the nomogram can be predictive criteria for TC patients with LM. Brain metastasis, liver metastasis, and larger tumor size were prognostic factors for CCS and OS among TC patients with LM.

Kernel Liu prediction approach in partially linear mixed measurement error models

ABSTRACT In this paper, we put forward ‘kernel Liu prediction approach’ instead of ‘kernel prediction approach’ under multicollinearity case in partially linear mixed measurement error model. We obtain the necessary and sufficient condition for the superiority of the linear combinations of the predictors in the sense of the matrix mean square error criterion and give the selection of the Liu biasing parameter via the Conceptual Prediction () criterion. The asymptotic normality condition is examined and the unknown covariance matrix of measurement errors circumstance is derived. We study a numerical example together with a Monte Carlo simulation study to evaluate the performance of the kernel Liu prediction approach at the end of this paper.

OR12-3 Identification of Predictive Criteria for the Primary Bilateral Macronodular Adrenal Hyperplasia Gene ARMC5: A European Series of 352 Unselected Patients.

Abstract Objective Primary Bilateral Macronodular Adrenal Hyperplasia (PBMAH) is a heterogeneous disease characterized by adrenal macronodules and variable levels of cortisol excess, with not clearly established clinical diagnostic criteria. PBMAH can be caused by germline inactivating variants of the tumor suppressor gene ARMC5. We aimed to better characterize ARMC5-mutated and wild-type patients and to identify predictive criteria for ARMC5 variants. Methods We included 352 consecutive index patients from 12 European centers, sequenced for germline ARMC5alteration because of PBMAH suspicion, regardless their clinical presentation. Clinical, biological and imaging data were collected retrospectively. Sensitivity, specificity, negative and positive predictive values for the prediction of ARMC5variant were calculated for various parameters. Results 53 patients (15.1%) carried 40 different ARMC5 germline pathogenic variants and showed a more distinct phenotype than non-mutated patients for cortisol excess (24-hour urinary free cortisol 2.32 vs. 1.11-fold ULN, respectively, p&amp;lt;0.001; plasma cortisol after 1 mg dexamethasone suppression test 337.5 vs. 142.4 nmol/L, respectively, p&amp;lt;0.001) and adrenal morphology (maximal adrenal diameter 104 vs. 83 mm, respectively, p&amp;lt;0.001; 9.8 vs. 3.2 adrenal nodules, respectively, p&amp;lt;0.001), with more frequent metabolic complications such as diabetes (51.0 vs. 35.4%, respectively, p=0.038) and hypertension (88.0 vs. 70.6%, respectively, p=0.014). Thus, ARMC5-mutated patients were more often surgically or medically treated in order to control cortisol excess (67.9 vs. 36.8%, respectively, p&amp;lt;0.001). Among operated patients, a bilateral adrenalectomy was more often performed in those carrying an ARMC5 pathogenic variant than in wild-type patients (56.7 vs. 32.3%, respectively, p=0.019). Even if all patients were more often primarily investigated in front of adrenal incidentaloma than clinical evidence for Cushing's syndrome (73 vs. 27%, respectively), ARMC5 patients were more often referred for Cushing's syndrome than wild-type patients (44 vs. 24%, respectively, p=0.004). To improve the ARMC5 mutation rate, the association of a clear bilateral adrenal involvement with evidence for autonomous cortisol secretion (defined at least by a plasma cortisol after 1 mg dexamethasone suppression test above 50 nmol/L) holds the better yield with a 27% specificity and a 20% positive predictive value, and a 100% sensitivity and negative predictive value, meaning that a useless genotyping could have been avoided for more than 20% of negative patients, without missing any mutated patient. Conclusion We report the largest series of index case patients investigated for ARMC5 with clinical characterization and confirm that ARMC5 pathogenic variants are associated with a more severe phenotype. In order to minimize negative ARMC5 screening, genotyping could be limited to clear bilateral adrenal involvement on imaging and autonomous cortisol secretion, with an optimum yield for routine clinical practice. These findings will also help better define PBMAH diagnostic criteria. Presentation: Sunday, June 12, 2022 11:30 a.m. - 11:45 a.m.

Prediction Criteria for the Formation of Refracture after Union of a Long Bone Fracture on the Basis of Hemodynamic Changes in the Tissues of the Area of Damage

We studied hemodynamic changes in the area of leg bone fracture and determined the prognostic criteria for refracture formation after achieved union. In Wistar rats (n=18), shin bone fracture with external fixation of the fragments was modeled. The union was formed 35 days after osteosynthesis, the device was removed at this term. In 5 cases, a refracture was formed after the termination of fixation. Hemodynamics and local temperature in the tissues in the area of injury were recorded before the start of the experiment and on days 21 and 35 of fixation. In rats with refracture after union, the blood circulation in the area of damage was characterized by a pronounced hypertonicity of the arteries of both large and small diameters, obstruction of venous outflow, and local hyperthermia. This hemodynamics in tissues in the area of damage can serve as an informative criterion for predicting the course of reparative osteogenesis.

Clinical and psychological ground of principles of prognostication of premature delivery risk

The objective: to assess the diagnostic significance of anamnestic and clinical-psychological factors and develop the prediction criteria for the threat of premature birth (PB). Materials and methods. An analysis of the data of pregnant women who were tested in the II and early III trimesters (screening is the I stage of the study) was carried out. The pregnant women were conditionally divided into two groups. The main group included 30 women whose further course of pregnancy was complicated by the threat of PB. The comparison group included 222 women without clinical manifestations of threat of PB during the current pregnancy. During the II stage of the study, the systematization of existing anamnestic and clinical-psychological factors among the examined women was performed. At the III stage, a comparative analysis of the frequency of the symptoms identified at the I stage was carried out in pregnant women in groups with the calculation of diagnostic coefficients (DC) of measures of informativeness (MI) according to formulas. Diagnostic (prognostic) tables were created for each factor, DC and MI were calculated based on the ratio of frequencies. According to the methodology for calculating the accuracy of the diagnostic decision to achieve a probability level of 95 % (p=0.05), the limit ∑DC is a constant = ±13, to achieve a probability of 99 % = ±20, to achieve a probability of 99.9% = ±30. If there is a factor in the column of the scale that is not included in the spectrum of exclusions, put a check mark in the “yes” column of the corresponding row. In the absence of such a check mark is placed in the “no” column of the corresponding row. Regarding the filling of each row, the sum of DC is calculated by adding up the indicated DCs, in the case of reaching the value of ∑DC, a preliminary diagnostic conclusion is made about the probability for threat of PB (at ∑DC = -13), which has a confidence level of 95 % (p=0.05). If the value of ∑DK = -20 is reached, a final diagnostic conclusion is made about the probability of 99 % for threat of PB (p=0.01). If the limit of the range is -13 &lt; ∑DC &lt; +13, the conclusion is significant because in such case its “p” is &gt; 0.05.Results. Based on the values ​​of DC and MI of Kullbak (valid signs), a clinical scale to predict threat of PB with a confidence level of 95 % (p=0.05) or 99 % (p=0.01) was developed. Among the informative signs (factors) for predicting of threat of PB the following factors were established: spontaneous miscarriage in the anamnesis, high personal and situational anxiety (45 points and above), IV and more pregnancies and artificial abortion in the anamnesis, as well as the level of neuroticism (16 points and above). Conclusions. It has been established that anamnestic and clinical-psychological factors, namely, miscarriage in the anamnesis, artificial abortion in the anamnesis, IV and more pregnancies, high levels of personal and situational anxiety and neuroticism, are important and effective criteria for predicting the threat of premature birth.

Tumor response assessment on imaging following immunotherapy.

In recent years, various systemic immunotherapies have been developed for cancer treatment, such as monoclonal antibodies (mABs) directed against immune checkpoints (immune checkpoint inhibitors, ICIs), oncolytic viruses, cytokines, cancer vaccines, and adoptive cell transfer. While being estimated to be eligible in 38.5% of patients with metastatic solid or hematological tumors, ICIs, in particular, demonstrate durable disease control across many oncologic diseases (e.g., in melanoma, lung, bladder, renal, head, and neck cancers) and overall survival benefits. Due to their unique mechanisms of action based on T-cell activation, response to immunotherapies is characterized by different patterns, such as progression prior to treatment response (pseudoprogression), hyperprogression, and dissociated responses following treatment. Because these features are not encountered in the Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1), which is the standard for response assessment in oncology, new criteria were defined for immunotherapies. The most important changes in these new morphologic criteria are, firstly, the requirement for confirmatory imaging examinations in case of progression, and secondly, the appearance of new lesions is not necessarily considered a progressive disease. Until today, five morphologic (immune-related response criteria (irRC), immune-related RECIST (irRECIST), immune RECIST (iRECIST), immune-modified RECIST (imRECIST), and intra-tumoral RECIST (itRECIST)) criteria have been developed to accurately assess changes in target lesion sizes, taking into account the specific response patterns after immunotherapy. In addition to morphologic response criteria, 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG-PET/CT) is a promising option for metabolic response assessment and four metabolic criteria are used (PET/CT Criteria for Early Prediction of Response to Immune Checkpoint Inhibitor Therapy (PECRIT), PET Response Evaluation Criteria for Immunotherapy (PERCIMT), immunotherapy-modified PET Response Criteria in Solid Tumors (imPERCIST5), and immune PERCIST (iPERCIST)). Besides, there is evidence that parameters on 18F-FDG-PET/CT, such as the standardized uptake value (SUV)max and several radiotracers, e.g., directed against PD-L1, may be potential imaging biomarkers of response. Moreover, the emerge of human intratumoral immunotherapy (HIT-IT), characterized by the direct injection of immunostimulatory agents into a tumor lesion, has given new importance to imaging assessment. This article reviews the specific imaging patterns of tumor response and progression and available imaging response criteria following immunotherapy.

Influence of different gypsum plasterboards on the fire performance of cold-formed steel walls

As typical fire protection sheathings, the thermal physical properties of gypsum boards may vary among manufacturers, which may affect the fire performance of gypsum-sheathed cold-formed steel (CFS) walls. Six different gypsum boards were selected for the sheathing of six mid-scale, non-load-bearing, CFS wall specimens, and fire tests were conducted under ISO 834 conditions. The results indicated that the insulation performance of gypsum boards may be related to the density and fibre content of gypsum boards. High-density gypsum boards have an improved heat absorption capacity. Adding fibre to the gypsum boards can effectively delay fire-induced fall-off of the gypsum boards. When gypsum boards with no visible fibre exhibit fire-induced fall off, their cold surface temperature fell between 560 °C and 710 °C, while that for gypsum boards with obvious fibre contained in fire exceeded 780 °C. Hence, from the perspective of safety, the performance variation of gypsum boards caused by different manufacturers should be considered in the fire design of CFS walls. A new prediction criterion was proposed to determine fire-induced fall-off of gypsum boards, namely, the cold surfaces of gypsum boards reaching 550 °C and a heating rate above 40 °C/min. The new criteria can clearly quantify the fire-induced fall-off time and temperature of gypsum boards according to their time–temperature curve. In addition, it is suggested to adopt fire-resistant gypsum boards as face-layer sheathing and to adopt standard gypsum boards as base-layer sheathing to make gypsum-sheathed CFS walls more cost-effective.

Experimental and theoretical investigation of mixed-mode I/II and I/III fracture behavior of PUR foams using a novel strain-based criterion

Brittle fracture in Polyurethane (PUR) foam is experimentally and theoretically investigated under mixed-mode I/II and I/III loading conditions. Original test data are generated to examine different criteria in prediction of the mixed-mode fracture behavior of PUR foam. To this end, edge notched disc bend (ENDB) specimen which has been proven to be a suitable test configuration for such loading conditions is used, and subsequently, fracture angles and fracture toughness values are obtained experimentally. Three different fracture criteria, including minimum strain energy density (SED), maximum principal stress (MPS), and the recently introduced strain-based criterion called ECD-SN – which is established based on considering an effective critical distance – are considered to theoretically estimate the fracture behavior of PUR foam. A comparison between the experimental and theoretical results revealed that the ECD-SN criterion gives a better prediction both for the fracture angles and the mixed-mode fracture toughness of PUR foam. The results indicated that considering effective critical distance instead of the traditional approach, which assumes the critical distance is constant as a material property and independent of the loading mode, can considerably increase the accuracy of the theoretical estimation.

Regional prediction and prevention analysis of rockburst hazard based on the Gaussian process for binary classification

Rockburst is a complex dynamic disaster in coal mining and affected by many factors. To accurately predict the rockburst hazard among complex influencing factors, a prediction model of rockburst hazard based on the Gaussian process for binary classification (GPC) was proposed after the identification of the intrinsic relationship between multiple factors of coal mines and rockburst. Through computerized machine learning and integrated intelligent analysis, the non-linear mapping of rockburst hazard and its influencing factors was established. The multi-factor pattern recognition model was constructed using artificial intelligence. The prediction criteria of the rockburst hazard probability and the hazard probability value of the prediction area unit were determined by applying neural network and fuzzy inference methods. In addition, the rockburst hazardous zone was classified, and the corresponding technical scheme for the prevention was put forward. The validity and feasibility of the regional prediction of rockburst hazard based on GPC were verified in the engineering practice. This method is highly targeted and can improve the accuracy and precision of rockburst prediction, thus contributing to the safe and efficient production of coal mines.

Development of maximum tangential strain (MTSN) criterion for prediction of mixed-mode I/III brittle fracture

A number of fracture criteria are available for predicting the cracking behavior under combined contribution of opening-tearing damage mechanism (i.e. mixed-mode I/III). But most of them have some limitations or discrepancies with the experimental results. In this research, a new form of maximum tangential strain criterion called 3D-MTSN is developed for predicting mixed-mode I/III fracture phenomenon. This criterion was used originally for analyzing the mixed-mode I/II fracture but we extended its ability for mixed mode I/III as well. Also, the influence of T-stress in addition to modes I and III stress intensity factors was also considered in driving the fracture toughness and fracture angle formulations of the 3D-MTSN criterion. According to this strain-based criterion it is shown that both sign and magnitude of T-stress can affect the fracture behavior of mixed mode I/III. In general, positive T-stress increases the mixed mode I/III fracture envelope and conversely negative sign of T-stress can decrease it. Meanwhile, the Poisson’s ratio (v) has noticeable influence on the mixed mode I/III fracture envelopes and by increasing v, the mixed mode fracture curve predicted by the generalized MTSN criterion shifts down except for those specimens having positive T-stress values and subjected to dominantly pure mode I loading conditions. The practical ability and validity of 3D-MTSN criterion is examined by predicting different sets of mixed mode I/III experimental results reported in the literature for different brittle and quasi-brittle materials tested with different test samples including edge-notch disc bend (ENDB), inclined single edge notch beam (ISENB) and semi-circular bend (SCB) specimens. A comprehensive comparison with the well-known 3D-MTS (stress-based) criterion was also performed. Compared to the other available energy-based fracture models, the presented 3D-MTSN criterion provided better estimations for the experimental results of different materials and specimens under dominantly mode III conditions.

Study produces unparalleled predictive criterion for glass forming ability

Advancing metallic glass materials research and development with artificial intelligence

The P-h2 relationship as a function of (hf/hm) in indentation

In the present study, a semi-empirical modeling of the mechanical response in pile-up mode is obtained by deriving the load-depth relationship during the indentation loading cycle. The advantage compared to the relations previously used is that this new expression is a function of the predictable criterion of the mode of deformation, (hf/hm), which makes it possible to distinguish the sink-in mode from the pile-up mode. A comparison between the proposed expression and the results of the instrumented indentation tests shows excellent agreement.