bluuebunny/crossref_metadata_2025_split huggingface dataset:
Minimisation of interference effects in thyristor converters by feedback/ forward control
Authors: Luo F.L. , Hill R.J. 
Published: August 2008

In industrial closed-loop control systems such as thyristor current converters, good system quality can be difficult to obtain, for example, because of the lack of complete compensation of interference by the feedback arrangement. This paper describes an application to such equipment of Feedback/Forward Control (FBFC), which can implement optimum regulation provided that the regulated output and the open-loop transfer function are both stable. The basic premise of the control scheme considered here is that, since there is zero steady-state error between reference and feedback signals, it is possible to replace the feedback circuit by a digital controller having a number of inputs; when the reference or feedback signal varies, the output of the controller will then follow the change, and the system output can reach a new steady-state with a minimum time lag (optimum regulation). FBFC achieves accurate system regulation by combining the usual advantages of feedback control with the anticipatory properties of feedforward control.
Analysis of swirl, viscosity and temperature effects on turbine flowmeters
Authors: Salami L.A. 
Published: August 2008

This paper shows that swirl has a great influence on turbine meter characteristics and the error per degree of swirl is about 2.5%. It also demonstrates that the viscosity effect on the turbine meter is not correlated by Reynolds' number especially at high viscosities. Range of viscosity covered is 1-400 centipoise. Temperature effects were shown to be better correlated using an empirical relation based on pulses per unit mass flow rather than pulses per unit volumetric flow. Temperature range covered is 20-60°C. A theoretical model has been proposed which gives a fair agreement with experimental results provided that the changes in the axial velocity profile with swirl are taken into consideration. The same model has been used to explain the effects of viscosity and temperature.
Finite element modelling of Bourdon tubes used in pressure and temperature gauges
Authors: Bansil M.S. , Abdullah F. 
Published: August 2008

A finite element program has been developed for the elastic analysis of Bourdon tubes used in both pressure and temperature sensing. The theory developed succeeds in enabling the three-dimensional Bourdon tube to be treated as a two-dimensional problem, by assuming that material properties and geometry do not change in one direction. The program was applied to several Bourdon tubes. Results for end-deflection data given by Bourdon tube manufacturers are compared with the finite-element-program results. These agree to within 10%. Also, stress patterns for two temperature Bourdon tubes are presented; one with edge grooves and one without. The post-processing showed that reduction in the level of stresses can be achieved by incorporating edge grooves. The use of such a model for Bourdon tube design is discussed briefly.
Occam structures in control applications
Authors: Jones D.I. 
Published: August 2008

Examples are given illustrating the use of the Occam programming language in control applications. It is demonstrated that numerical algorithms for real-time control and computer aided design may be configured for multiprocessor systems using the Occam approach. The three examples are: 1. Numerical integration., 2. Gradient minimisation with array line search ; 3. Inverse dynamics for a robot manipulator.
Thermocouple and RTD approximations for the design of portable microprocessor-based simulators
Authors: Dooley L.S. , Evanst W.A. 
Published: August 2008

Thermocouple and R TD simulators are instruments that fall into the 'intelligent instrument' category and are increasingly being used for calibration and fault diagnosis purposes in applications where thermocouple and resistance-temperature detectors (RTDs) are used for the sensing of temperature, These instruments depend on storing and retrieval of the transducer characteristics so that, in operation, the instrument will meet and exceed the British Standards for thermocouples and RTDs. This paper contains a detailed study of the problem of storage and generation of the transducer characteristics, concluding that linear curve fitting combined with the exchange algorithm offers the best solution for instruments based on cheap, low-powered microprocessors with limited instruction sets.
Microcomputer-controlled robotic equipment for precision TIG welding
Authors: Morris E. , Lucas J. 
Published: August 2008

The TIM robot has been designed for use with high-precision welding using the TIG (tungsten-inert-gas) process. Details are given of the design and construction of a five degrees of freedom machine, having cartesian and wrist movements. Details are also given of the operating features and the microcomputer and electronic hardware necessary to achieve these design features. An Intel 8085 8-bit microcomputer was used to control the welding operation; the workpiece position and movement and the time sequence of the welding cycle could be controlled in accordance to a predetermined set of parameters stored in memory. The approach adopted for software development is also described. Emphasis is placed on the use of a high-level language to achieve flexibility, with subroutines in assembly language for faster response. Path entry was carried out by moving the torch around the joint and recording by the point-to-point technique. Complex joint paths, for example circular, square and triangular paths, can be reproduced accurately, and such welds have been used as illustrations of the flexibility of the machine. In designing the machine for TIG welding operations, the controller was fully protected against HF airborne noise present during arc initiation.
PWORLD: A Precedent-Based Global Simulation
Authors: Schrodt Philip A. 
Published: August 2008

A "world model" is constructed where precedent searching is one of the primary driving mechanisms. The simulation assumes that nations in the system are utility maximizers but that they have relatively primitive decision mechanisms and are strongly influenced by their previous short-term successes and those of other states in the system. This model of foreign-policy decision making has been heavily influenced by recent artificial intelligence studies and simulations. States in the simulation can follow one of three distinct strategies to maximize growth: imperialism, militarism, or trade. In each of these modes, a state can either increase or decrease its level of behavior, or it can switch modes. Decisions to switch are based on the success of the policy in increasing simulated GNP relative to earlier pro jections of how much GNP would increase. If a policy is clearly not working, a nation implements the reverse of it, if the policy is not producing major improvements, the nation randomly experiments or looks at the success of other nations in the system and follows whatever has worked for them. If a policy is clearly successful, it is continued. The simulation was run using a system vaguely characteristic of the 19th-century world system, with 5 large, 5 medium, and 10 small nations. The resulting behavior is generally plausible, with bounded and fairly diverse activity depending on the random experimentation involved Because of the weak bounded rationality, the system does not lock on to a single pattern of behavior based on initial conditions, and so, for example, situations exist where medium powers eventually become stronger than the initial major powers. The most common pattern is one of a combination of trade links and imperialism, with about half the minor power being colonized and some exchange of colonies occurring through conflict. Keywords: artificial intelligence, foreign policy, global simulation, precedent-searching simulation, world modeling, simulation.
Use of prescription and nonprescription medications and supplements by cancer patients during chemotherapy: questionnaire validation
Authors: Hanigan Marie H , dela Cruz Brian L , Thompson David M , Farmer Kevin C , Medina Patrick J 
Published: August 2008

Background. Cancer patients take medications for coexisting disease and self-medicate with over-the-counter drugs (OTCs). A complete analysis of the use of prescription drugs, OTCs, and supplements during cancer treatment has never been done. Methods. The study developed and validated a self-administered questionnaire on the use of concomitant medications by patients undergoing treatment with chemotherapy. The questionnaire listed 510 prescription medications, OTCs, and supplements (including vitamins, minerals, and herbs). Fifty-two subjects completed the questionnaire while visiting the infusion clinic to receive chemotherapy. On a subsequent visit the subjects brought their medications to the clinic and a pharmacist reviewed their completed questionnaire. Results. Ninety-six percent of the subjects reported taking prescription medications within 3 days prior to chemotherapy, 71% reported taking OTCs and 69% reported use of supplements. The subjects took an average of 5.5 (range 0—13) prescription drugs, 2.2 (0—20) OTCs, and 1.9 (0—11) supplements. Twenty-one drugs were each taken by at least 10% of the subjects. Acetaminophen was taken by 59.6% of the subjects. One subject reported taking five acetaminophen-containing drugs. The questionnaire's sensitivity was 92.0%, specificity 99.9%. Conclusion. Within 3 days prior to chemotherapy, subjects took an average of 9.6 concomitant medications, many of which alter drug metabolism and or disposition. In clinical trials, multivariate analysis of all concomitant medications could add to clinically relevant data to identify drug interactions that negate or potentiate the efficacy of cancer treatment regimens. In some instances, apparent resistance of tumors to chemotherapy may be the result of drug interactions. J Oncol Pharm Practice (2008) 14: 123—130.
Screening and management of osteoporosis in breast cancer patients on aromatase inhibitors
Authors: Gibson Kelli , O'Bryant Cindy L 
Published: August 2008

Objective. Breast cancer patients are at an increased risk of osteoporosis due to age, cancer, chemotherapy, and aromatase inhibitor therapy. This retrospective review determined if patients treated with aromatase inhibitors received appropriate screening and management for osteoporosis. Design. University of Colorado Cancer Center breast cancer patients treated with aromatase inhibitor therapy during July 2005 through July 2006 were studied. Data was collected for each patient from the time of breast cancer diagnosis up to April 2007. The study endpoints included (1) appropriate screening for osteoporosis, (2) incidence of osteoporosis diagnosis, and (3) initiation of appropriate drug therapy for bone loss. Appropriate management was defined as adherence to the 2003 American Society of Clinical Oncology guidelines for bone health issues in women with breast cancer. Results. Of the 54 patients included in this study, 12 (22.2%) had no DEXA scans documented, 22 (40.7%) patients received a baseline DEXA scan and 8 (14.8%) patients received baseline and yearly DEXA scans. During the study timeline, 26 (48%) patients were diagnosed with osteopenia and 4 (7%) patients were diagnosed with osteoporosis. Forty-one (75.9%) patients received calcium and vitamin D therapy. Bisphosphonate therapy was received by less than one-third of the osteopenic patients and three-fourths of the osteoporotic patients. Conclusions. The majority of patients were not adequately screened which may have falsely lowered the diagnosis of osteoporosis resulting in omission of drug therapy. All high-risk patients should receive calcium and vitamin D therapy and be evaluated for bisphosphonate therapy. Screening and medical management for osteoporosis in breast cancer patients on aromatase inhibitors is an important area for clinical intervention. J Oncol Pharm Practice (2008) 14: 139—145.
Characterization of the occurrence of ifosfamide-induced neurotoxicity with concomitant aprepitant
Authors: Howell Joshua E , Szabatura Audrea H , Hatfield Seung Amy , Nesbit Suzanne A 
Published: August 2008

Purpose. Ifosfamide is metabolized by the cytochrome P450 system to its active form, ifosforamide mustard. A potential side effect is neurotoxicity, often manifesting as confusion, hallucination, or seizure. Aprepitant, a neurokinin-1 inhibitor, is recommended for highly and moderately emetogenic chemotherapy regimens and may interfere with the metabolism of ifosfamide as it inhibits CYP3A4. The objective of the study is to identify if an increase in the incidence of neurotoxicity may be associated with the use of aprepitant with concomitant ifosfamide. Methods. A retrospective study of inpatients with sarcoma who received a two or four-day regimen of MAI (mesna, doxorubicin, and ifosfamide) between January 1, 2004 and December 31, 2006 was conducted. Data collection focused on characterizing neurotoxicity of patients receiving ifosfamide with or without aprepitant. Correlation between serum creatinine, albumin, liver function tests, age, gender, and total doses of ifosfamide was examined. Results. A total of 45 patients received ifosfamide of which 23 (51%) were male and 24 (53%) received aprepitant. All baseline characteristics were similar for those who received aprepitant versus those who did not. No significant differences were noted between patients with or without neurotoxicity for age, gender, or liver enzymes. Eight patients (18%) of 45 developed neurotoxicity of which six (75%) of those patients also received aprepitant. A trend of increased occurrence of neurotoxicity was noted with aprepitant administration (6 vs. 2 patients respectively, p = 0.176), although a statistical difference was not observed. A relative risk of 2.6 (95% CI, 0.47—26.6) was associated with the addition of aprepitant. Conclusions. An increased risk was identified for ifosfamide-induced neurotoxicity associated with aprepitant use; however, the observed difference was not statistically significant. The necessity of aprepitant given in association with ifosfamide may need to be reconsidered due to this risk. J Oncol Pharm Practice (2008) 14: 157—162.
An Unusual Case of Effort Thrombosis of the Subclavian Vein Successfully Treated by Resection and Saphenous Vein Grafting
Authors: Human Lance 
Published: August 2008

An unusual case of effort thrombosis of the left subclavian vein, occurring in a fifteen-year-old girl who indulged in regular, vigorous horseriding, is pre sented. This is the youngest case reported in the world so far. The majority of patients are usually young men and the condition usually involves the right upper extremity. Complete fibrosis of a segment of the subclavian vein where it crosses the first rib occurred as a result of repeated trauma to the vein from repeated, sudden, forceful muscular contractions of the shoulder girdle due to excessive and vigorous, almost daily horseriding over a fifteen-month period. Claviculectomy of the medial half of the clavicle with resection of the nar rowed and thrombosed dilated segment and saphenous vein grafting gave an excellent result.
In-Situ Bypass Graft: Comparison of Two Techniques
Authors: Kaynan Arieh , Sheth Mahendra 
Published: August 2008

Two techniques of in-situ bypass for lower limb revascularization were com pared over a period of fifteen months (between July, 1986, and October, 1987). Twelve patients underwent surgery employing the Leather and Karmody tech nique (group I). Fourteen patients underwent surgery employing the LeMaitre technique (group II). Throughout the study period, 11 of 12 grafts in group I and all grafts in group II remained patent. One patient in group I underwent a below-knee amputation. One patient in group II died of myocardial infarction. Skin problems developed in 3 patients (25%) of group I and in 1 patient (7.1%) of group II. Average time for performance of the procedure was four hours and fifteen minutes with the Leather and Karmody technique and three hours and thirty minutes with the LeMaitre technique. Though both techniques are equally good for limb salvage, the LeMaitre technique is easier to master and simpler to perform.
Anatomic and Histologic Studies on the Valves of the Venous System in Lower Extremities
Authors: Sun Jian-Min , Zhang Pei-Hua 
Published: August 2008

Anatomic and histologic studies of vein valves were made on 50 adult cadav ers (100 lower extremities). In the deep and superficial venous trunks, big valves were found mostly with two cuspids. At the inlets of their branches, small valves monocuspid in shape were commonly found. There was no valve in the common iliac vein, and the percentages of the other veins containing valves were: external iliac 42%, common femoral 51%, deep femoral 88%, superficial femoral 100%, popliteal 93%, tibioperoneal trunk 26%, and all the deep veins in the lower leg, including tibial and peroneal 100%. The valves in the deep venous trunk are much stronger than those in the long saphenous vein. They can resist a retrograde pressure of 180 to 420 and 100 to 260 mmHg respectively. The clinical value of this study concerning the staged arteriovenous reversal in the treatment of severely ischemic limbs and the etiology of the primary incompetence of the deep veins of the lower extremity are discussed.
Evaluation of a Partial Open Beam Laser Probe in Laser-Assisted Angioplasty
Authors: Diethrich Edward B. , Timbadia Ela , Bahadir Ilhan 
Published: August 2008

A partial open beam laser delivery system was evaluated in a series of 664 lower extremity laser-assisted an gioplasties performed in 349 consecu tive patients with atherosclerotic oc clusive disease. The 2.5 mm, metal- capped, fiberoptic probe featured a 2 μm central window through which 10-20% active laser light was emitted. In combination with the thermal ef fect produced by the metal tip, the partial beam probe was designed to more effectively ablate calcified ath eroma that had been resistant to the closed beam hot tip probes. In 28 (4%) angioplasties, lesions recalcitrant to the closed beam probe were treated with the partial beam delivery system. This probe opened 23 (82%) arteries without difficulty. Three of the 5 probe failures were in lengthy occlusions (> 10 cm) in the superficial femoral artery. In the other 2 lesions, the delivery system opened a channel too small for the probe's body to pass easily. The partial beam laser delivery system works satisfactorily in recana lizing many of the peripheral vessels resistant to the standard closed beam probe.
Significance of Distal Runoff and Concomitant Lumbar Sympathectomy in Bypass Surgery for Patients with Thromboangiitis Obliterans
Authors: Doko Soroku , Katsumura Tatsuki , Fujiwara Takashi , Inada Hiroshi , Masaki Hisao 
Published: August 2008

The graft patency of bypass surgery to or distal to the popliteal artery for 29 lower extremities with thromboangiitis obliterans (TAO) and for 67 lower ex tremities with arteriosclerosis obliterans (ASO) and six factors influencing graft patency were studied and a new method of scoring distal runoff determined from angiographic findings was employed. Early graft occlusion (EGO, < one month) was found only in lower extremi ties with distal runoff of 5 or less and more frequently in patients with TAO than in those with ASO, although distal runoff in TAO patients (n=29) was signifi cantly less than that in ASO. Among TAO patients with distal runoff of 5 or less, EGO (n = 7) was found only in those without concomitant lumbar sympathectomy (CLS), but the dif ference in distal runoff between patients with EGO and those without it was not significant. From these results, it was concluded that: (1) EGO in patients with TAO is probably due to poor distal runoff with high constrictivity and (2) CLS for such patients could improve EGO, which, in turn, would result in a better cumula tive patency rate.
Carotid Endarterectomy: Experience at a Community Hospital
Authors: Vo Nghia M. , Floresguerra Carlos , Sutter Janice , Watson Scott , Blankenship Joan , Stanton Paul E. 
Published: August 2008

One hundred and nineteen consecutive carotid endarterectomies (CEAs) performed on 86 patients have been reviewed. Thirty-three patients had bilateral CEAs. The indications were: (1) asymptomatic stenosis or ulceration (29%); (2) transient ischemic attack and amaurosis fugax (58%); and (3) reversible is chemic neurologic deficit and stroke (13%). Sixty percent of patients were shunted and 40% were not. There were 1 postoperative death in the first group and 2 strokes in each group. The overall stroke and death rates were 3.4% and 0.8% respectively. Eighty-eight percent and 83% of patients were alive and stroke free respectively during the forty-two-month follow-up period. The authors conclude that (1) CEA can be safely performed at a community hospital and (2) routine shunting or no shunting does not affect the patient's outcome.
Cost:Benefit Analysis of Elective Retroperitoneal Aortic Bypass
Authors: Markowitz Ira P. , Bell William H. , Senkowsky Jon , Fernandez Jose I. , Swetnam Jeffrey A. , Rubino Linda J. , Kerstein Morris D. 
Published: August 2008

Of 72 consecutive patients needing abdominal aortic surgery, the transperi toneal approach (TA) was used in 34 patients. In this TA group, with a mean age of fifty-eight years, 28 patients had aortoiliac or aortobifemoral grafts. Of the 38 patients operated via the retroperitoneal approach (RA), 27 had aortoiliac disease and 11 had aneurysms. In the RA group, the mean age was fifty-nine years; 32 patients in this group had aortofemoral grafts. The groups were simi lar with regard to hypertension, heart disease, obstructive pulmonary disease, previous myocardial infarction, and stroke. The TA was associated with the larger intraoperative blood loss (1,100 mL) when compared with the RA (mean: 400 mL). Intraoperative crystalloid re quirements were significantly higher for the TA (5,500 mL) versus the RA (3,000 mL). Similarly, the intraoperative blood requirements were higher for the TA (3.0 units packed red blood cells [PRBC]) than the RA (1.0 unit PRBC). The numbers of units of PRBC transfused after surgery were significantly less with the RA (1.25 units) compared with the TA (0.5 unit). The total operative time for the TA was 225 minutes; the time for the RA was 165 minutes (p < 0.01). The number of hospitalized postoperative days in the TA was 11.5 compared with 6 days in the RA; average number of days of nasogastric intubation was 4 days for the TA compared to 0.25 day for the RA; and tolerance for regular food was initiated at 5.5 days in the TA compared with 1.5 days in the RA. The number of hours of postoperative intubation for the TA was an average of 19.5 compared with 4.5 for the RA; the number of postoperative verbal orders in the TA was 14.0 compared with 4.5 in the RA; and complications in the TA were six times greater than in the RA. Most of the TA complications were pulmonary; these were not present in the RA. The incidence of wound infection was zero in both groups; mortality was zero in both groups. The average hospital cost of the TA was $20,125.26 compared with $5,164.05 for the RA. The RA for abdominal aortic vascular surgery is more cost effective than the TA.
Aneurysm of the Extracranial Internal Carotid Artery Seven Years After Trauma: A Case History and Literature Review
Authors: Vanmaele R.G. , Vaneerdeweg W. , Haenen L. , Koekelkoren E. 
Published: August 2008

A false aneurysm of the extracranial internal carotid artery developed seven years after the effects of a motorcar accident had been treated in the Depart ment of Otolaryngology. Excision and reconstructive surgery were successfully performed in the Division of Vascular Surgery. Literature study shows aneurysms of the extracranial carotid artery to be a rare condition. Trauma is mentioned as a major cause. Active treatment is man datory. Surgical resection and reconstruction should be preferred.