Diamond Bit Drilling Research

1973 ◽  
Vol 95 (1) ◽  
pp. 256-262
Author(s):  
T. B. Dellinger ◽  
B. J. Livesay
Keyword(s):  
Multiple Regression ◽  
Flow Rate ◽  
Penetration Rate ◽  
Full Scale ◽  
Hydraulic Lift ◽  
Regression Analyses ◽  
Diamond Drilling ◽  
Data Points ◽  
Rotary Speed ◽  
Diamond Bit

Fundamental relationships of the parameters; penetration rate, bit weight, rotary speed, bit horsepowers, flow rate, and pressure were developed using eight full-scale, oilfield diamond drilling bits under laboratory-controlled conditions. One thousand five hundred data points, with all the parameters, were analyzed with 642 plots and 131 multiple-regression analyses. The hydraulic lift under the diamond bit has been accounted for in order to obtain relationships of mechanical bit weight with torque and penetration.

A Multiple Regression Approach to Optimal Drilling and Abnormal Pressure Detection

1974 ◽  
Vol 14 (04) ◽  
pp. 371-384 ◽  
Author(s):  
A.T. Bourgoyne ◽  
F.S. Young
Keyword(s):  
Multiple Regression ◽  
Field Data ◽  
Penetration Rate ◽  
Drilling Process ◽  
Rotary Drilling ◽  
Natural Logarithm ◽  
Drilling Parameters ◽  
Abnormal Pressure ◽  
Drilling Data ◽  
Rotary Speed

Abstract Over the past decade, a number of drilling models have been proposed for the optimization of The rotary drilling process and the detection of abnormal pressure while drilling. These techniques have pressure while drilling. These techniques have been largely based Upon limited held and laboratory data and often yield inaccurate results. Recent developments in onsite well monitoring systems have made possible the routine determination of the best mathematical model for drilling optimization and pore pressure detection. This modeling is accomplished through a multiple regression analysis of detailed drilling data taken over short intervals. Included in the analysis are the effects of formation strength, formation depth, formation compaction, pressure differential across the hole bottom, bit diameter and bit weight, rotary speed, bit wear, and bit hydraulics.This paper presents procedures for using the regressed drilling model for selecting bit weight rotary speed, and bit hydraulics, and calculating formation pressure from drilling data. The application of the procedure is illustrated using field data. Introduction Operators engaged in the search for hydrocarbon reserves are facing much higher drilling costs as more wells are drilled in hostile environments and to greater depths. A study by Young and Tanner has indicated that the average well cost per foot drilled is increasing at approximately 7.5 percent/ year. Recently, more emphasis has been placed on the collection of detailed drilling data to aid in the selection of improved drilling practices.At present, many people are using one drilling model for optimizing bit weight and rotary speed, a different drilling model for optimizing jet bit hydraulics, and yet another model for detecting abnormal pressure from drilling data. Each model has been based on meager laboratory and field data. We have tried here to combine what is known about the rotary drilling process into a single model, develop equations for calculating formation pore pressure and optimum bit weight, rotary speed, and jet bit hydraulics that are consistent with that model, and provide a method for systematically "calibrating" the drilling model using field data. DRILLING MODEL The drilling model selected for predicting be effect of the various drilling parameters, xj, on penetration rate, dD/dt, is given by penetration rate, dD/dt, is given by(1) when Exp (z) is used to indicate the exponential function ez. The modeling of drilling behavior in a given formation type is accomplished by selecting the constants a, through a 8 in Eq. 1. Since Eq. 1 is linear, those constants can be determined from a multiple regression analysis of field data. EFFECT OF FORMATION STRENGTH The constant a, primarily represents the effect of formation strength on penetration rate. It is inversely proportional to the natural logarithm of the square proportional to the natural logarithm of the square of the drillability strength parameter discussed by Maurer. It also includes the effect on penetration rate of drilling parameters that have not yet been mathematically modeled; for example, the effect of drilled solids. EFFECT OF COMPACTION The terms a2x2 and a3x3 model the effect of compaction on penetration rate. x2 is defined by(2) and thus assumes an exponential decrease in penetration rate with depth in a normally compacted penetration rate with depth in a normally compacted formation. The exponential nature of the normal compaction trend is indicated by the published microbit and field data of Murray, and also by the field data of Combs (see Fig. 1). SPEJ P. 371

WISC—R IQ Estimates from the Luria-Nebraska Neuropsychological Battery

1993 ◽  
Vol 77 (2) ◽  
pp. 683-688 ◽  
Author(s):  
Thomas A. Boyd ◽  
Stephen R. Hooper
Keyword(s):  
Multiple Regression ◽  
Predictive Accuracy ◽  
Psychiatric Patients ◽  
Total Sample ◽  
Full Scale ◽  
Stepwise Multiple Regression ◽  
Chronological Age ◽  
Regression Equations ◽  
Regression Analyses ◽  
Mean Differences

Multiple regression equations predicting WISC—R IQs from Luria-Nebraska T scores and subjects' chronological age were developed and cross-validated on a total sample of 152 adolescent psychiatric patients. Data from a randomly drawn subsample of 100 subjects were entered into three stepwise multiple-regression analyses to derive equations predicting WISC—R IQs. These equations were applied to the remaining subsample ( n = 52) as were the equations developed by McKay, et al. (1981) for estimating adult WAIS IQs. Mean differences, correlations, and classification hit rates between the two sets of predicted IQs and the actual WISC—R IQs were examined. Findings were similar to those of previous studies examining the predictive relationship between the Luria-Nebraska and adult intelligence. As expected, chronological age entered significantly into all three stepwise multiple-regression analyses. The newly derived equations had significantly higher correlations with the WISC—R for Verbal and Full Scale IQs and significantly better predictive accuracy for Full Scale IQ. Rates of IQ misclassification warrant caution in the use of these methods, but it is concluded that the equations derived here predict about as well as do short forms of the WISC—R.

Language and Literacy Predictors of Dialect Density Among School-Age African American Children From Two Geographic Regions

2020 ◽  
Vol 51 (3) ◽  
pp. 807-820
Author(s):  
Lena G. Caesar ◽  
Marie Kerins
Keyword(s):  
African American ◽  
Multiple Regression ◽  
Oral Language ◽  
East Coast ◽  
Geographic Region ◽  
Literacy Skills ◽  
School Age ◽  
Regression Analyses ◽  
Geographic Regions ◽  
American Children

Purpose The purpose of this study was to investigate the relationship between oral language, literacy skills, age, and dialect density (DD) of African American children residing in two different geographical regions of the United States (East Coast and Midwest). Method Data were obtained from 64 African American school-age children between the ages of 7 and 12 years from two geographic regions. Children were assessed using a combination of standardized tests and narrative samples elicited from wordless picture books. Bivariate correlation and multiple regression analyses were used to determine relationships to and relative contributions of oral language, literacy, age, and geographic region to DD. Results Results of correlation analyses demonstrated a negative relationship between DD measures and children's literacy skills. Age-related findings between geographic regions indicated that the younger sample from the Midwest outscored the East Coast sample in reading comprehension and sentence complexity. Multiple regression analyses identified five variables (i.e., geographic region, age, mean length of utterance in morphemes, reading fluency, and phonological awareness) that accounted for 31% of the variance of children's DD—with geographic region emerging as the strongest predictor. Conclusions As in previous studies, the current study found an inverse relationship between DD and several literacy measures. Importantly, geographic region emerged as a strong predictor of DD. This finding highlights the need for a further study that goes beyond the mere description of relationships to comparing geographic regions and specifically focusing on racial composition, poverty, and school success measures through direct data collection.

Full Scale Study of Biological Phosphorus Removal Processes

1985 ◽  
Vol 17 (11-12) ◽  
pp. 297-298 ◽  
Author(s):  
Takao Murakami ◽  
Atsushi Miyairi ◽  
Kazuhiro Tanaka
Keyword(s):  
Flow Rate ◽  
Phosphorus Removal ◽  
Phosphorus Release ◽  
Full Scale ◽  
Aeration Tank ◽  
Biological Phosphorus Removal ◽  
Mode 2 ◽  
Removal Processes ◽  
Biological Phosphorus ◽  
Total P

In Japan various biological phosphorus removal processes have recently been researched by laboratory or pilot plant scale studies and most of them have shown good results. Based on these results, the Japan Sewage Works Agency has conducted a full scale study of the biological phosphorus removal process from June 1982 until February 1983, which was the first full scale operation of this process in Japan. The main purpose of the study was to evaluate phosphorus removal efficiency and also nitrogen removal efficiency of the process and in addition, to ascertain the important operating factors of the process. For the study a treatment train of a large scale sewage treatment plant was remodelled. The aeration tank of 3.825 m3 volume was divided into four equal cells. The whole train including return sludge line was operated entirely independently of the other trains. During the experiment the train was operated under two different modes, Mode 1 and Mode 2. In Mode 1, the train was operated as an A/O process, the first cell of the aeration tank being anaerobic and the other cells oxic. In Mode 2, the train was operated as a Modified Phoredox process. In this case, the first cell was anaerobic, but the second cell was anoxic and nitrified liquor was returned to it from the end of the oxic cells. Mode 1 and Mode 2 were further divided into many ‘runs' and the flow rate varied between 12,550 m3 d−1 and 25,270 m3 d−1 , corresponding to retention times of 7.3 hours and 3.6 hours, respectively. Throughout the experimental period the mean value of influent (primary effluent) total-P concentration was 3.38 mg 1−1 , and that of the final effluent was 0.47 mg 1−1 . A cumulated frequency curve of the data showed that about 93% of measured effluent total-P was below 1.0 mg l−1 . Therefore, it can be concluded that with these influent total-P levels, biological phosphorus removal processes can sufficiently satisfy the effluent standard of 1 mg 1−1 total-P. Even when the process was operated as a Modified Phoredox Process, no obstruction to phosphorus removal because of nitrification was observed and phosphorus removal remained good. However, since the sewage treatment plant treated influent from a combined sewerage system, phosphorus removal was sometimes affected by heavy rainfalls. In such cases phosphorus release in the anaerobic cell was insufficient because of increased influent NOx concentration and accordingly increased denitrification level in the anaerobic cell. Therefore, as a result, enhanced phosphorus uptake in the following cells could not be observed. Higher process stability can be expected if an effective countermeasure to high influent NOx concentration can be made. Influence of flow rate fluctuation on the process was also studied. The treatment train was operated for a week under a daily flow rate fluctuation pattern which ranged between 460 m3 hr−1 and 820 m3 hr−1 . Nevertheless, the effluent total-P concentration showed no increase and stayed constantly lower than 0.5 mg 1−1. The oxidation reduction potential (ORP) was an effective control index to evaluate the degree of phosphorus release in the anaerobic cell. Water temperature did not affect phosphorus release and uptake rates.

THE EVALUATION OF SELF-MONITORING ATTRIBUTES

1991 ◽  
Vol 19 (3) ◽  
pp. 205-215 ◽  
Author(s):  
Arts Jiujias ◽  
Peter Horvath
Keyword(s):  
Regression Analysis ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Regression Analyses ◽  
Self Monitoring

Eighty-six Canadian female undergraduates attributed self-monitoring traits to a target presented on videotape, and evaluated her in terms of liking. Attributed self-monitoring was negatively correlated with attraction to the target and was the only predictor of attraction in a multiple regression analysis. Multiple regression analyses with subscales of attributed self-monitoring as predictors suggested that the evaluations may be the result of the attributed unpredictability of the high self-monitoring prototype.

Phenotypic selection in a population of Crepis tectorum ssp. pumila (Asteraceae)

1992 ◽  
Vol 70 (1) ◽  
pp. 89-95 ◽  
Author(s):  
Stefan Andersson
Keyword(s):  
Life History ◽  
Multiple Regression ◽  
Large Scale ◽  
Demographic Data ◽  
Phenotypic Selection ◽  
Direct Selection ◽  
Surprising Result ◽  
Regression Analyses ◽  
Ecotypic Differentiation ◽  
Crepis Tectorum

A 3-year demographic study was conducted to reveal targets of selection on morphology and life history in a population of Crepis tectorum ssp. pumila, a winter annual plant confined to calcareous grasslands (alvars) on the Baltic island of Öland (south Sweden). I calculated the selection differential to describe the change in the mean value of a character due to selection and used multiple regression analyses to partition the direct effect of selection on the trait from indirect responses of selection on other traits. Rosette leaf number, a convenient measure of plant size, was strongly correlated with both viability and fertility (fitness). There was also a strong relationship between fitness and the extent to which the plants expressed traits characterizing this particular taxon. Multiple regression analyses indicated direct selection favouring plants with deeply lobed leaves and a densely branched stem, two distinctive traits of ssp. pumila believed to be adaptive in the alvar habitat. Only stem height was subject to both direct and indirect selection in the wrong direction; taller individuals were more successful than those with a shorter stem, a surprising result considering the inferred advantage of a short stature in the exposed alvar habitat. Selection on other traits assumed to be ecologically important (germination time, flowering time, and seed size) was found to be either absent or variable in direction when other traits were held constant. The failure of plants to survive to the flowering stage in the last two summers indicates strong selection for plants that produce a high percentage of dormant seeds. Overall, the contemporary selection regime as revealed by demographic data was only partly congruent with predictions regarding historical selection pressures based on large-scale patterns of variation (ecotypic differentiation). Key words: Crepis tectorum, ecotypic differentiation, life history, morphology, phenotypic selection.

Copying, Reading, and Writing of Kana and Simple Forms by Japanese Preschoolers

1988 ◽  
Vol 66 (2) ◽  
pp. 387-394
Author(s):  
Jun Yamada ◽  
Miyuki Sasaki ◽  
Naoko Motooka
Keyword(s):  
Multiple Regression ◽  
Good Predictor ◽  
Quality Measure ◽  
Writing Achievement ◽  
Regression Analyses ◽  
Reading And Writing ◽  
Conventional Form ◽  
Form Quality ◽  
Japanese Kana ◽  
Children's Reading

42 Japanese preschoolers were administered tasks of copying, reading, and writing of Japanese kana (cursive syllabic letters) and simple forms. Multiple regression analyses were used to determine whether two kana-copying measures, speed and span, make significant contributions to children's reading and writing achievement after a conventional form-quality measure had been controlled. Analysis showed that speed or span accounts uniquely for a significant and sizable amount of the variance of reading and writing, suggesting that kana-copying is a good predictor of reading and writing for Japanese preschoolers.

Relationship Between Spirituality and Distress in Ascetics

2021 ◽  
pp. 003329412110434
Author(s):  
Rudra B. Bhandari ◽  
Nidhi Chaudhry ◽  
Sarita Devi
Keyword(s):  
Multiple Regression ◽  
Negative Relationship ◽  
Spiritual Intelligence ◽  
Self Report ◽  
Regression Analyses ◽  
Psychosomatic Health ◽  
Spirituality And Health ◽  
Medical Index ◽  
The Relationship ◽  
Health Questionnaires

The relation between spirituality and health has been argued for decades. The study aimed to ascertain the extent and nature of the relationship between spirituality quantified in terms of Spiritual Intelligence (SI) and distress in ascetics. Sixty-three Hindu ascetics aged 31.3 ± 6.6 years were sampled from Patanjali Yogpeeth, India. Participants’ distress and spiritual levels were measured by using the Cornell Medical Index Health Questionnaires (CMHIQs) and Spiritual Intelligence Self-Report Inventory-24 (SISRI-24), respectively. Multiple regression analyses showed an insignificant negative relationship between SI and distress implying SI as a predictor of psychosomatic health.

Predictors of quality of life and functioning in schizophrenia

2021 ◽  
Vol 25 (4) ◽  
pp. 341-356
Author(s):  
Octavia Căpățînă ◽  
◽  
Cristina Pojoga ◽  
Bogdan Savu ◽  
Mihaela Fadgyas-Stănculete ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Multiple Regression ◽  
Predictive Factors ◽  
Negative Symptoms ◽  
Clinical Symptoms ◽  
Cross Sectional Study ◽  
Regression Analyses ◽  
Cross Sectional ◽  
General Functioning

Background: In order to pursue recovery, Quality of life (QoL) and general functioning in patients with schizophrenia are milestones that need to be addressed in the treatment of the disease. The major aim of the present study was to examine the relationship between QoL, functionality and symptoms, and clinical characteristics of the disease, and to identify whether the two domains of negative symptoms, avolition/apathy and diminished expression, are predictive factors for the quality of life and functionality in patients diagnosed with schizophrenia. In the present cross-sectional study, 87 patients diagnosed with schizophrenia completed a thorough battery of instruments evaluating: clinical symptoms, stigma, QoL, functionality, socio-demographic and clinical variables. Multiple regression analyses were performed to test the significance of predictor variables for QoL and functionality. Multiple regression analyses revealed that internalized stigma, depression, and excitement were significant predictors for the variability of QoL, and experiential deficit and cognitive symptoms were significant predictors of the variability of functioning. In patients with schizophrenia, functioning and quality of life are two related but different constructs. Even though they are strongly associated, they have different predictive factors. The clinical implication of these results is that both of these constructs should be assessed and that the strategies for improving them should be different.

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