Borehole resistivity curves near spheroidal masses

Geophysics ◽  
1980 ◽  
Vol 45 (10) ◽  
pp. 1513-1522 ◽  
Author(s):  
T. L. Dobecki

Modeling of in situ energy extraction processes (e.g., coal gasification and oil shale retorting) has been examined by assuming the affected zones may be described by oblate or prolate spheroids of lowered electrical resistivity. The purpose of the model study is to determine if such subsurface bodies may be monitored and defined by electrical resistivity measurements made in boreholes away from the reaction zone. Solutions of the Laplace equation in (1) oblate and (2) prolate spheroidal coordinate systems enable theoretical determination of the electrical potential distribution as would be measured in a borehole near an anomalous body of oblate or prolate shape. The body is assumed to be enclosed within an infinite, homogeneous mass. Normal (pole‐pole) type curves of (1) electrical resistivity for various electrode spacings (sounding curves) and (2) electrical resistivity for various positions in the borehole (vertical profiling) are developed for both oblate and prolate spheroidal models using spheroids of increasing size as a sensitivity parameter. Modeling results verify that an oblate body of the same cross‐sectional shape as a prolate body produces the larger anomaly. For the various size and resistivity parameters specified in this study, deviations from the homogeneous case (i.e., no spheroid) range from 3 percent for the smallest oblate and prolate bodies up to 60 percent for the largest modeled oblate body. If a ±5 percent uncertainty because of instrumentation, field technique, or random noise may be assumed, this implies a lower limit to the size of a detectable body. On this basis, the smaller spheroids of this study would not be detectable. However, both sounding and profiling type measurements offer promise as effective monitoring tools, and, if repeated over the period of process time, may enable process growth estimates. Further, because the oblate case is independent of azimuth while the prolate is not, measurements made in a series of borings surrounding the process center may describe the shape tendency (oblate versus prolate) of the process and determine directivity (azimuth of prolate major axis) of the process if existent.

Author(s):  
Courtney H. Graham ◽  
S. E. Jones ◽  
Mary L. Hughes ◽  
Kathryn G. Lee

In an earlier paper [1], a fundamental analysis of penetrator stability was presented that resulted in a simple criterion for penetrator design. This criterion was based on some features of long rod penetrator design that could be anticipated: namely, length, cross-sectional area of the shank, area moment of inertia of the cross-section, and the elastic properties of the body material. A number of approximations were made in this early work to reduce the complexity of the modeling effort. Of course, this led to some uncertainties in the results. The purpose of this paper is to explore some of the more prominent sources of uncertainty and to refine the stability estimate. Of specific concern is the effect of a crude approximation on the lowest Eigen function in the problem. In this paper, a small parameter is identified and used to find a regular perturbation solution. The results are found to be in good agreement with those presented earlier.


Author(s):  
W. Brünger

Reconstructive tomography is a new technique in diagnostic radiology for imaging cross-sectional planes of the human body /1/. A collimated beam of X-rays is scanned through a thin slice of the body and the transmitted intensity is recorded by a detector giving a linear shadow graph or projection (see fig. 1). Many of these projections at different angles are used to reconstruct the body-layer, usually with the aid of a computer. The picture element size of present tomographic scanners is approximately 1.1 mm2.Micro tomography can be realized using the very fine X-ray source generated by the focused electron beam of a scanning electron microscope (see fig. 2). The translation of the X-ray source is done by a line scan of the electron beam on a polished target surface /2/. Projections at different angles are produced by rotating the object.During the registration of a single scan the electron beam is deflected in one direction only, while both deflections are operating in the display tube.


Author(s):  
H. Kung ◽  
A.J. Griffin ◽  
Y.C. Lu ◽  
K.E. Sickafus ◽  
T.E. Mitchell ◽  
...  

Materials with compositionally modulated structures have gained much attention recently due to potential improvement in electrical, magnetic and mechanical properties. Specifically, Cu-Nb laminate systems have been extensively studied mainly due to the combination of high strength, and superior thermal and electrical conductivity that can be obtained and optimized for the different applications. The effect of layer thickness on the hardness, residual stress and electrical resistivity has been investigated. In general, increases in hardness and electrical resistivity have been observed with decreasing layer thickness. In addition, reduction in structural scale has caused the formation of a metastable structure which exhibits uniquely different properties. In this study, we report the formation of b.c.c. Cu in highly textured Cu/Nb nanolayers. A series of Cu/Nb nanolayered films, with alternating Cu and Nb layers, were prepared by dc magnetron sputtering onto Si {100} wafers. The nominal total thickness of each layered film was 1 μm. The layer thickness was varied between 1 nm and 500 nm with the volume fraction of the two phases kept constant at 50%. The deposition rates and film densities were determined through a combination of profilometry and ion beam analysis techniques. Cross-sectional transmission electron microscopy (XTEM) was used to examine the structure, phase and grain size distribution of the as-sputtered films. A JEOL 3000F high resolution TEM was used to characterize the microstructure.


Author(s):  
T.B. Ball ◽  
W.M. Hess

It has been demonstrated that cross sections of bundles of hair can be effectively studied using image analysis. These studies can help to elucidate morphological differences of hair from one region of the body to another. The purpose of the present investigation was to use image analysis to determine whether morphological differences could be demonstrated between male and female human Caucasian terminal scalp hair.Hair samples were taken from the back of the head from 18 caucasoid males and 13 caucasoid females (Figs. 1-2). Bundles of 50 hairs were processed for cross-sectional examination and then analyzed using Prism Image Analysis software on a Macintosh llci computer. Twenty morphological parameters of size and shape were evaluated for each hair cross-section. The size parameters evaluated were area, convex area, perimeter, convex perimeter, length, breadth, fiber length, width, equivalent diameter, and inscribed radius. The shape parameters considered were formfactor, roundness, convexity, solidity, compactness, aspect ratio, elongation, curl, and fractal dimension.


2015 ◽  
Vol 8 (3) ◽  
pp. 161
Author(s):  
Samuel Gideon

This research was conducted as a learning alternatives for study of CT (computed tomograpghy) imaging using image reconstruction technique which are inversion matrix, back projection and filtered back projection. CT imaging can produce images of objects that do not overlap. Objects more easily distinguishable although given the relatively low contrast. The image is generated on CT imaging is the result of reconstruction of the original object. Matlab allows us to create and write imaging algorithms easily, easy to undersand and gives applied and exciting other imaging features. In this study, an example cross-sectional image recon-struction performed on the body of prostate tumors using. With these methods, medical prac-titioner (such as oncology clinician, radiographer and medical physicist) allows to simulate the reconstruction of CT images which almost resembles the actual CT visualization techniques.Keywords : computed tomography (CT), image reconstruction, Matlab


2017 ◽  
Vol 19 (1) ◽  
pp. 7-11
Author(s):  
Vivi Linda Fristianti ◽  
Nur Hidayat ◽  
Slamet Iskandar

Background : IDD problem is a serious problem, 33% of districts in Indonesia are endemic, 21% of endemic mild, moderate endemic 5% and 7% by weight endemic. Urine Iodine Excretion (EYU) illustrates the iodine intake of a person, because 90% of the iodine that enter the body are excreted through the urine. Blocking agents are substances certain minerals such as iron, manganese and calcium, which can bind iodine in groundwater. Objectives : This study aims to determine the relationship of Fe content in ground water sources against EYU levels in school children in the village of the District Cerme Panjatan Kulon Progo. Methods : An observational analytic research with cross sectional design. Data collection is done in May - June 2015. Location research Elementary School Cerme, District Panjatan Kulon Progo. The subjects of the study as many as 34 children in elementary school classroom Cerme 3, 4 and 5 were taken by simple random sampling. Well water and urine samples taken students then tested the iron in the Central Health Laboratory test Yogyakarta and iodine in urine in Magelang BP2GAKY Laboratory. Data analysis using Spearman Range test with significancy level : 0.05. Result : Fe content in the ground water is below the normal threshold is <0.3 mg / L. While levels EYU school children who are under the optimal level of 5.9%, the optimal level of 32.4%, and the optimum levels above 61.8% (optimal: 100 - 199μg / L). Conclusion : There was no significant relationship between the Fe content in groundwater with levels of EYU in school children in District Panjatan Kulon Progo (p = 0.447).   Keywords: Fe, EYU


2018 ◽  
Vol 1 (2) ◽  
pp. 114
Author(s):  
Wahdaniah Wahdaniah ◽  
Sri Tumpuk

Abstract: Routine blood examination is the earliest blood test or screening test to determine the diagnosis of an abnormality. Blood easily froze if it is outside the body and can be prevented by the addition of anticoagulants, one of which Ethylene Diamine Tetra Acetate (EDTA). Currently available vacuum tubes containing EDTA anticoagulants in the form of K2EDTA and K3EDTA. K3EDTA is usually a salt that has better stability than other EDTA salts because it shows a pH approaching a blood pH of about 6.4. The purpose of this research is to know the difference of erythrocyte index results include MCH, MCV and MCHC using K3EDTA anticoagulant with K2EDTA. This research is a cross sectional design. This study used venous blood samples mixed with K2EDTA anticoagulant and venous blood mixed with K3EDTA anticoagulants, each of 30 samples. Data were collected and analyzed using paired different test. Based on data analysis that has been done on MCH examination, p value <0,05 then there is a significant difference between samples with K3EDTA anticoagulant with K2EDTA to erythrocyte index value. Then on the examination of MCV and MCHC obtained p value <0.05 then there is no significant difference between samples with K3EDTA anticoagulant with K2EDTA to erythrocyte index value.Abstrak: Pemeriksaan darah rutin merupakan pemeriksaan darah yang paling awal atau screening test untuk mengetahui diagnosis suatu kelainan. Darah mudah membeku jika berada diluar tubuh dan bisa dicegah dengan penambahan antikoagulan, salah satunya Ethylene Diamine Tetra Acetate (EDTA). Dewasa ini telah tersedia tabung vakum yang sudah berisi antikoagulan EDTA dalam bentuk  K2EDTA dan  K3EDTA. K3EDTA  biasanya berupa garam yang mempunyai stabilitas yang lebih baik dari garam EDTA yang lain karena menunjukkan pH yang mendekati pH darah yaitu sekitar 6,4. Tujuan dari penelitian ini adalah untuk mengetahui perbedaan hasil indeks eritrosit meliputi MCH, MCV dan MCHC menggunakan antikoagulan K3EDTA dengan K2EDTA. Penelitian ini merupakan penelitian dengan desain cross sectional. Penelitian ini menggunakan sampel darah vena yang dicampur dengan antikoagulan K2EDTA dan darah vena yang dicampur dengan antikoagulan K3EDTA, masing-masing sebanyak 30 sampel. Data dikumpulkan dan dianalisis menggunakan uji beda berpasangan. Berdasarkan analisis data yang telah dilakukan pada pemeriksaan MCH didapatkan nilai p < 0,05 maka ada perbedaan yang signifikan antara sampel dengan antikoagulan K3EDTA dengan K2EDTA terhadap nilai indeks eritrosit. Kemudian pada pemeriksaan MCV dan MCHC didapatkan nilai p < 0,05 maka tidak ada perbedaan yang signifikan antara sampel dengan antikoagulan K3EDTA dengan K2EDTA terhadap nilai indeks eritrosit.


Author(s):  
J.S. McMurray ◽  
C.M. Molella

Abstract Root cause for failure of 90 nm body contacted nFETs was identified using scanning capacitance microscopy (SCM) and scanning spreading resistance microscopy (SSRM). The failure mechanism was identified using both cross sectional imaging and imaging of the active silicon - buried oxide (BOX) interface in plan view. This is the first report of back-side plan view SCM and SSRM data for SOI devices. This unique plan view shows the root cause for the failure is an under doped link up region between the body contacts and the active channel of the device.


2018 ◽  
Vol 8 (4) ◽  
pp. 28-33
Author(s):  
Mao Nguyen Van ◽  
Thao Le Thi Thu

Background: In practice it was difficult or impossible to have a correct diagnosis for the lymphoid proliferation lesions based on only H.E standard histopathology. In addition to histopathology, the application of immunohistochemistry was indispensable for the definitive diagnosis of the malignant or benign tumours and the origin of the tumour cells as well. Objectives: 1. To describe the gross and microscopic features of the suspected lesions of lymphoma; 2. To asses the expression of some immunologic markers for the diagnosis and classification of the suspected lesions of lymphoma. Materials and Method: Cross-sectional research on 81 patients diagnosed by histopathology as lymphomas or suspected lesions of lymphoma, following with immunohistopathology staining of 6 main markers including LCA, CD3, CD20, Bcl2, CD30 and AE1/3. Results: The most site was lymph node 58.1% which appeared at cervical region 72.3%, then the stomach 14.9% and small intestine 12.4%. The other sites in the body were met with lower frequency. Histopathologically, the most type of the lesions was atypical hyperplasia of the lymphoid tissue suspecting the lymphomas 49.4%, lymphomas 34.5%, the other diagnoses were lower including inflammation, poor differentiation carcinoam not excluding the lymphomas, lymphomas differentiating with poor differentiation carcinomas. Immunohistochemistry showed that, LCA, CD3, CD20, Bcl2, CD30 and AE1/3 were all positive depending on such type of tumours. The real lymphomas were 48/81 cases (59.3%), benign ones 35.8% and poor differentiated carcinomas 4.9%. Conclusion: Immunohistochemistry with 6 markers could help to diagnose correctly as benign or malignant lesions, classify and determine the origin of the tumour cells as lymphocytes or epithelial cells diagnosed by histopathology as lymphomas or suspected lesions of lymphomas. Key words: histopathology, immunohistochemistry, lymphomas, poor differentiated carcinomas, hyperplasia, atypicality


2019 ◽  
Vol 31 (3) ◽  
pp. 251-256

Cirrhosis of liver is one of the common medical problem in daily clinical practice and one of the leading causes of morbidity and mortality. Zinc is an essential trace elements for human and plays in many biological roles in the body. Among them, zinc deficiency is thought to be involved in metabolism of ammonia and causes hyperammonia that worsen hepatic encephalopathy. This study aimed to find out the severity of cirrhosis of liver was by Child Turcotte Pugh score and to investigate the associations between serum zinc level and severity of cirrhosis. A hospital-based cross-sectional descriptive study was performed on 78 patients with different underlying causes of cirrhosis of liver at the Medical Units of Yangon General Hospital and Yangon Specialty Hospital. Among the study population, Child grade A was found to be 28.21%, Child grade B was 30.77% and Child grade C was 41.03%. Regarding result of serum zinc level, 62.8% were low level, 28.2% were within normal level and 8.9% were high level. Mean value of serum zinc level in grade A was 0.68 mg/l, grade B was 0.54 mg/l and grade C was 0.48 mg/l (p=0.00). It was found out that there was a high prevalence of zinc deficiency in severe cirrhotic patients. The zinc level was significantly lowest among patients with Child-Pugh C as compare to those with Child-Pugh B and C. Severity of zinc deficiency should be requested for supplementation therapy in cirrhotic patients as to prevent complications such as hepatic encephalopathy, hepatocellular carcinoma and liver failure. Screening for zinc deficiency may need in these patients with more advanced cirrhosis because it seems to be a marker of advanced liver disease and it can be deducted that awareness of serum zinc level among cirrhotic patients is very important in clinical practice.


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