bluuebunny/crossref_metadata_2025 huggingface dataset:
Advancing Cervical Cancer Prevention in India: Implementation Science Priorities
Authors: Krishnan Suneeta , Madsen Emily , Porterfield Deborah , Varghese Beena
Published: November 2013

Cervical cancer is the leading cause of cancer mortality in India, accounting for 17% of all cancer deaths among women aged 30 to 69 years. At current incidence rates, the annual burden of new cases in India is projected to increase to 225,000 by 2025, but there are few large-scale, organized cervical cancer prevention programs in the country. We conducted a review of the cervical cancer prevention research literature and programmatic experiences in India to summarize the current state of knowledge and practices and recommend research priorities to address the gap in services. We found that research and programs in India have demonstrated the feasibility and acceptability of cervical cancer prevention efforts and that screening strategies requiring minimal additional human resources and laboratory infrastructure can reduce morbidity and mortality. However, additional evidence generated through implementation science research is needed to ensure that cervical cancer prevention efforts have the desired impact and are cost-effective. Specifically, implementation science research is needed to understand individual- and community-level barriers to screening and diagnostic and treatment services; to improve health care worker performance; to strengthen links among screening, diagnosis, and treatment; and to determine optimal program design, outcomes, and costs. With a quarter of the global burden of cervical cancer in India, there is no better time than now to translate research findings to practice. Implementation science can help ensure that investments in cervical cancer prevention and control result in the greatest impact.
Performance of dovetailed synthetic fibers in concrete
Authors: Richardson Alan E. , Coventry Kathryn A. , Boussoffara Riyadh
Published: November 2013

This research investigated the bond strength and toughness of a range of widely used commercially available synthetic Type 2 structural fibers defined within BS EN 14889 and compared these against novel prototype dovetailed (DT) synthetic Type 2 structural fibers. The DT shapes are three in number when viewed across the diameter of the circular DT fiber, and they run longitudinally, creating an open flute effect. Synthetic fibers tend to be made from low-modulus materials when compared with steel crack control products, and they suffer a greater diameter reduction and increase in length when compared with steel, for an equal load. Diameter reduction of fibers in concrete causes debonding and eventual failure. DT fibers are designed to offer additional bond when a diameter reduction occurs under load. Fibers were cast into concrete cubes to a depth of half their length and pulled out recording load and extension to ultimate failure. The findings showing large degrees of toughness were available when using DT fiber technology. The DT fibers transferred less bond stress at the point of the initial pull out prior to the DT feature of the fiber taking effect. The DT fiber under test provided additional grip through the contraction of the internal faces of the DT features when under load. Further work is needed to determine the optimum DT fiber diameter and aspect ratio that may provide increased bond stress while retaining large degrees of toughness.
Cementing Light & Tight: A CBM Cementing Story
Authors: Kumar Animesh , Kumar Anjani
Published: November 2013

The CBM process is an amalgam of oilfield and coal-mining practices that have merged and often require the investigation of parameters that were previously ignored. Production of coal bed methane (CBM) in a short time has become an important industry, providing an abundant, clean-burning fuel in an age when concerns about pollution and fuel shortages preoccupy the thoughts of many Indians.

This paper excerpts the successful use of high strength & low density cement slurry used for primary and remedial cementing jobs in Coal Bed Methane wells in the Raniganj block of Eastern India.

Cement is placed as a sheath across coal seams in coal bed methane wells primarily for hydraulic isolation and to support the casing. Designing a cement job for coal seam wells requires contemplating factors beyond those considered in cementing conventional oil & gas wells.

The successful cementing job in coal seams faces several challenges, viz. cement invasion into coal seams, losses during jobs, low fracture gradient and low formation temperature. Since, most of the CBM wells need to fracture the cement sheath between casing and formation, thus the set cement should not only have high compressive strength, but high tensile strength as well.

The unique advantages of high strength & low density cement slurries are: Reduced density to take care of low fracture gradient of coal seams.Prevent invasion and loss circulation.Eliminate the need for stage cementing.High compressive strength.

The paper also explains the importance of flush-type spacer for better hole cleaning. It is also be used to cure loss circulation zones.

This paper shares case histories and best practices developed for successful cementing operations in CBM wells; and experience of designing, simulating and real time data acquisition.

With the application of real time data acquisition, downhole ECDs (equivalent circulating densities) of fluids can be monitored and kept in check.
Evaluation of WARMF model for flow and nitrogen transport in an agricultural watershed under a cold climate
Authors: Dayyani Shadi , Prasher Shiv O. , Madani Ali , Madramootoo Chandra A. , Enright Peter
Published: November 2013

The Watershed Analysis Risk Management Framework (WARMF) model is adapted to simulate flow and nitrate-N transport in an agricultural watershed in Quebec, Canada. The model was evaluated for the St. Esprit Watershed (24.3 km2), which is a part of the 210 km2 St. Esprit river basin, a tributary of the L'Assomption Watershed (4,220 km2). WARMF's hydrologic calibration and validation was performed using data from the gauge station located at the outlet of the watershed. Water-quality data collected were used to guide water quality calibration/validation. Simulations were carried out from 1994 to 1996; data from 1994 and 1995 were used for model calibration and data from 1996 were used for model validation. The model performed reasonably well in simulating the hydrologic response and nitrate losses at the outlet of the watershed. The R2 between the observed and simulated monthly stream flow for calibration was 0.92, and that for validation was 0.94. The corresponding coefficients of efficiency (E) were 0.89 and 0.91. The R2 and E values for calibration/validation of NO3−-N loads simulation were 0.89/0.84 and 0.86/0.75, respectively. Thus, the model simulated monthly flow and nitrogen losses with a good degree of accuracy over the entire year.
Comparison of Accuracy Among Pedometers from Five Japanese
Manufacturers
Authors: Osawa So , Tabuchi Hisaaki , Nemoto Kenichi , Tokimasa Shuhei , Misaki Shotaro , Okuhara Masao , Terasawa Koji
Published: November 2013

The reliability of commercially available pedometers is not known in detail. Therefore, the present study
examines the accuracy and reliability of the FS500 (Acos), HJ301 (Omron), EX700 (Yamax), FB727 (Tanita) and TW600
(Citizen) pedometers to count steps and measure energy expenditure at various walking speeds. Twenty individuals (age,
32.5 ± 15.3 years; body mass index, 22.0 ± 1.6 kg/m2) walked at three speeds for 6 min. Step-counts and energy
expenditure determined by each pedometer were compared with actual values. All five pedometers accurately measured
steps at all speeds, but tended to underestimate expended calories to within 50% of the actual amount of energy
expenditure. The correlation coefficients (R) between actual energy expenditure and pedometer values were between 0.74
and 0.87. Thus, feedback about energy expenditure is somewhat inaccurate. In contrast, step counts are very accurate, and
thus pedometers are useful tools with which to indicate daily exercise levels.
Yoked Versus Self-Controlled Practice Schedules and Performance on
Dual-Task Transfer Tests
Authors: Sanli Elizabeth A. , Lee Timothy D.
Published: November 2013

The authors examined yoked versus self-controlled practice schedules to determine their influence in immediate
and delayed dual-task performance. The task was to propel a small disc along a smooth table top, with the purpose of
stopping it in a specified target area. Participants in the self-controlled schedule group chose the order in which eight
acquisition targets, differing in distance from a home position, were practiced during acquisition. Members of a control group
followed identical schedules to yoked participants in the self-controlled group. The authors hypothesized that those in the
self-controlled group would perform with less error on retention and transfer tests and with more error on dual-task transfer
tests in comparison to those in the yoked group. No differences in performance on retention, transfer, or dual-task tests were
found. Possible reasons for the similar performance between groups include the provision of choice over blocks of rather than
individual trials and feelings of autonomy in both groups due to choice as to how to propel the disc.
Learning Effects of Interactive Whiteboard Pedagogy for Students in Taiwan from the Perspective of Multiple Intelligences
Authors: Chen Hong-Ren , Chiang Chih-Hao , Lin Wen-Shan
Published: November 2013

With the rapid progress in information technology, interactive whiteboards have become IT-integrated in teaching activities. The theory of multiple intelligences argues that every person possesses multiple intelligences, emphasizing learners' cognitive richness and the possible role of these differences in enhanced learning. This study is the first to investigate the influence of interactive whiteboards on the learning effectiveness of 4th-grade science students in Taiwan from the perspective of multiple intelligences. The experiment in this study was based on a quasi-experimental design. The results indicated that the learning achievement of the students taught using interactive whiteboards was greater than that of the students taught using lectures. Among the students in the experimental group using interactive whiteboards, the learning achievement of the students with weaker logical-mathematical intelligence was higher than that of those with strong logical-mathematical intelligence. In other words, it can be inferred that the interactive whiteboards achieved good learning effects even for the students with weak logical–mathematical intelligence.
The effect of salinity on germination, emergence, seed yield and biomass of black cumin
Authors: Faravani Mahdi , Emami Davazdeh , Gholami Ali , Faravani Akram
Published: November 2013

Salinity sensitivity of black cumin (Nigella sativa L.) was studied to
determine salinity effects on germination, emergence, biological yield, seed
yield and plant height. A set of experiments were conducted under completely
randomized design in the germinator, greenhouse and field. Seeds of black
cumin were grown in a growth chamber irrigated with normal water, electric
conductivity (EC) of 0.3 dS m-1 as the control, and treatments amended with
NaCl to obtain EC from 3 to 39 dS m-1. Different EC treatments (3-39 dS m-1,
3-15 dS m-1 and 3-9 dS m-1) were applied at different phenological stages of
germination, emerging and seed setting, respectively. The effect of salinity
on seed germination, germination rate, shoot length, root length, seedling
weight, root to shoot ratio and seed vigor was significant at p<0.01. The
highest germination rate (94.8%) was observed at the salinity of 3 dS m-1 and
no germination was observed at the salinity of 36 dS m-1. Increase of
salinity from 0.3 (control) up to 15 dS m-1 significantly (p<0.01) influenced
the rate and percentage of emergence. The highest germination percentage
(52.5%) and emergence rate (9.2 seedlings per day) were achieved in the
control treatment. Seed yield, biomass and plant height were affected
significantly (p<0.05) by different salinity treatments. The essential oil
percentage was not significantly affected by salinity stress. With an
increase in the salinity level from 0.3 to 9 dS m-1, the average seed yield
and biological yield were decreased from 105.5 to 40.2 g m-2 and from 550.2
to 268.6 g m-2 respectively.
Effect of vermicompost and vermicompost extract on oil yield and quality of peppermint (Mentha piperita L.)
Authors: Ayyobi Hossein , Peyvast Gholam-Ali , Olfati Jamal-Ali
Published: November 2013

Organic fertilizers have beneficial effects on plants growth and quality.
However, vermicompost increases electrical conductivity in soil due to
increased salinity associated with continued usage. The experiment was
conducted in a research field at the University of Guilan to determine
effects of 7 Mt ha-1 of cow manure vermicompost, vermiwash prepared from 7 Mt
ha-1 of vermicompost, leachate vermicompost + vermiwash, 50 Mt ha-1 municipal
solid waste compost (MSWC), chemical fertilizer (NPK 50-0-300) and no
fertilization as a control on peppermint yield and quality. Fertilizer type
affected all measured characteristics except number of nodes, stem fresh
weight, total phenols and antioxidant capacity. Plants treated with
vermicompost, vermiwash or leachate vermicompost + vermiwash were the tallest
and had the highest levels of chlorophyll a, chlorophyll b, total chlorophyll
and carotenoids. Plants treated with vermicompost or vermiwash had the
highest total plant fresh weight, leaf fresh weight and total fresh yield.
The leachate vermicompost, vermiwash and vermicompost can be used as organic
fertilizers for sustainable peppermint cultivation.
Prediction of excess molar volumes of selected binary mixtures from refractive index data
Authors: Vuksanovic Jelena , Bajic Divna , Ivanis Gorica , Zivkovic Emila , Radovic Ivona , Serbanovic Slobodan , Kijevcanin Mirjana
Published: November 2013

The excess molar volumes of twenty two binary mixtures containing various
groups of organic compounds: alcohols (ethanol, 1-propanol, 1,2-propanediol,
1,3-propanediol and glycerol), ketone (acetone), ester (butyl lactate),
lactam (N-methyl-2-pyrrolidone), PEGs (PEG 200, PEG 400) and aromatics
(benzene, toluene and pyridine) were predicted from the refractive index
data, using three types of equations coupled with several mixing rules for
refractive index calculations: the Lorentz-Lorenz, Dale-Gladstone, Eykman,
Arago-Biot, Newton, and Oster. The obtained results were analysed in terms of
the applied equation and mixing rule and the nature of interactions between
the mixtures? components.
Simulation-based calculations of the proton dose in phase change memory cells
Authors: Zdjelarevic Nevena , Knezevic Ivan , Vujisic Milos , Timotijevic Ljubinko
Published: November 2013

Monte Carlo simulations of proton irradiation on phase change memory cells
were conducted and the proton dose, in both the whole memory cell and in its
active layer, calculated. The memory cell was modeled by a multi-layer stack
consisting of two TiW electrodes and ZnS-SiO2 films as insulators surrounding
the active region. Materials considered for the active region were Ge2Sb2Te5,
AgSbSe2, and Si2Sb2Te5. The effects of exposing phase change memory cells to
proton beams were investigated for various thicknesses of phase change
materials and different proton energies. Radiation-induced changes in the
investigated memory cells are presented, including the accumulation of atomic
displacements and the thermal heating of the active region. Possible effects
of these changes on cell operation are discussed.
Mechanical eye injuries in children aged 0-15 years treated at the Clinic of Eye Diseases in Belgrade: Frequency, causes and preventive measures
Authors: Jovanovic Milos , Medarevic Aleksandar , Knezevic Miroslav , Krstic Vera
Published: November 2013

Introduction. Eye injuries represent a significant problem in children.
Objective. The aim of the study was to determine the incidence and causes of
the eye injury and to propose measures of the eye injury prevention in
children up to 15 years of age. Methods. This was a retrospective study of
552 children with the eye injuries treated at the Clinic of Eye Diseases in
Belgrade during the period March 1999 to February 2010. Gender and age of the
children, time of injury, the type and site of injuries, visual acuity upon
admission and at discharge, as well as the time of surgery in relation to
time of injury were analyzed. Results. The ratio between the injured boys and
girls was 3.6:1. The highest percentage of injured children was in the group
6-10 years old (39.7%); the injuries were almost evenly distributed according
to months during the year and days during the week. The percentages of severe
closed and open injuries of the eyeball were almost equal. Visual acuity upon
discharge and subsequent follow-up examinations were significantly improved
after the applied treatment in comparison with the visual acuity upon
admission. Conclusion. Eye injuries in children still represent a severe
health problem. Regarding the youngest age group of children, adults are
mainly responsible for these injuries due to their lack of attention, while
in older children these injuries are the result of the production and
distribution of inappropriate toys and a failure to implement the legal
traffic regulations applicable to children. The prevention of eye injuries is
essential.
Laboratory monitoring of the haemostatic system changes during orthotopic liver transplantation
Authors: Novakovic-Anucin Sladjana , Gnip Sanja , Canak Visnja , Jurisic Djurdjina , Radovic Pavica , Erdeljan Svetlana , Milosevic Zoran , Mitic Gorana
Published: November 2013

Introduction. In liver diseases, all components of the haemostatic system are
changed and the degree of dysfunction is proportional to hepatocellular
damage. During the liver transplantation, values of haemostatic parameters
show substantial changes, while postoperatively there is a gradual
normalisation of the haemostatic system function. Objective The aim was to
monitor the changes of the haemostatic system intraoperatively and
postoperatively, including the dynamics at which physiological values of
parameters are reached after transplantation. Methods. There were 17
cadaveric transplantations performed at the Clinical Centre of Vojvodina in
the period from June 2008 to February 2012. The following parameters were
tested: platelets, activated partial thromboplastin, prothrombin and thrombin
time, fibrinogen, euglobulin clot lysis time, D-dimer, antithrombin and
heparinemia. The results were presented intraoperatively in phases of
transplantation, and postoperatively from day 1 to day 7, ending with
postoperative day 14. Results. During transplantation, the most pronounced
disorders among those observed are: thrombocytopenia (96?66.1?109/L),
prolonged activated partial thromboplastin (1.80?0.8 R), prothrombin
(1.59?0.4 R) and thrombin time (2.03?1.7 R), hypofibrinogenemia (2.13?0.5
g/L), hyperfibrinolysis (29?12.0 min), increase of D-dimer (1393?1220.4
ng/mL) and decrease of antithrombin (61?18.0%). Further monitoring after
transplantation from postoperative day 1 revealed a gradual normalisation in
the values, reaching physiological values for all parameters on postoperative
day 14, except for the sustained high value of D-dimer (2606?1055.1 ng/mL).
Heparinemia was within the prophylactic range (0.26?0 IU/mL). Conclusion.
Thorough monitoring of the haemostatic system parameters in liver
transplantations is of great importance, as it enables the use of optimal
substitution therapy during and after transplantation, as well as an adequate
postoperative thromboprophylaxis. Our study has shown normalisation of
investigated laboratory parameters within 7-14 days after transplantation.
Sexual and reproductive behaviour of young female internet users in Serbia
Authors: Rasevic Mirjana , Sedlecki Katarina
Published: November 2013

Introduction. Investigation of sexual and reproductive behaviour of youth in
Serbia has not been performed by Internet, although it is their popular
information and communication channel. Objective. Analysis of the Internet
acceptability among adolescent females as a research method for sexual and
reproductive behaviour, identification of the common girl from Serbia, which
is informed via the Internet, as well as an overview of the most important
problems in the field of sexual and reproductive health of our adolescents.
Methods. The possibility of using the Internet is perceived on the basis of
the number of girls aged 19?20 years who responded to certain questions asked
on the website of the Association of Reproductive Health of Serbia, and
reliability of the findings by monitoring the consistency of the obtained
responses. Girl?s profile is defined according to most commonly selected
answer to a particular issue, and the most important problems by selecting
answers to some questions chosen by a significant proportion of patients.
Results. Internet has proven to be the accepted research tool among young
people, according to a large number of adolescent females who responded to
the given questionnaire. The common girl lives in the city (78%), with
parents (53%), in the functional family (78%) and belongs to a higher
economic stratum (47%). She declares having many friends (44%), being a
student, and financially completely relying on parents (67%). She had first
sexual intercourse at the age of 17 (20%) and sexual experience with one
partner (46%). Her main motive for sexual activity is being in love (64%),
and is satisfied with her sexual life (64%). She prefers condom as a
contraceptive method, has not been pregnant (90%), and has not been diagnosed
with STI (85%). At the same time, serious problems, which may affect sexual
and reproductive health, have been identified in a significant proportion of
respondents. Conclusion. Internet has a great potential for defining the
model of sexual and reproductive behavior of youth, and offers the
possibility of alleviating these problems by a variety of activities,
including sending motivational messages via Internet.
Lateral extracavitary approach to spine
Authors: Ivetic Drazen , Spaic Milan , Antic Branislav
Published: November 2013

Introduction. This paper describes the lateral extracavitary approach to the
lumbar spine using the three?quarter prone position. Owing to unsatisfied
results of the posterior approaches to spine in patients with the ventral
compressive lesions, many ventral approaches as well as lateral extracavitary
approach have been developed. Case Outline. A patient with tumor (chordoma)
of L3 vertebral body was operated on by means of ventral compression of cauda
equina; the tumor had paraspinal propagation. Lateral extracavitary approach
was used with a patient in three?quarter prone position, and corpectomy with
the anterior stabilisation was performed followed by posterior transpedicular
stabilisation through the same approach. Complete tumor removal and excellent
neurological improvement were achieved. Conclusion. This approach provides
safe ventral decompression of the spinal cord; it also enables the anterior
and posterior instrumental stabilisation through the same incision and in the
same position during the intervention. The three?quarter prone position
allows excellent view of the dural sac.
Pseudoachondroplasia: A case report
Authors: Radlovic Vladimir , Smoljanic Zeljko , Radlovic Nedeljko , Jakovljevic Miroslav , Lekovic Zoran , Ducic Sinisa , Pavicevic Polina
Published: November 2013

Introduction. Pseudoachondroplasia (PSACH) is an autosomal dominant
osteochondrodysplasia due to mutations in the gene encoding cartilage
oligomeric matrix protein. It is characterized by rhizomelic dwarfism, limb
and vertebral deformity, joint laxity and early onset osteoarthrosis. We
present the girl with the early expressed and severe PSACH born to clinically
and radiographically unaffected parents. Case Outline. A 6.5-year-old girl
presented with short-limbed dwarfism (body height 79.5 cm, <P5; -32%) and
normal craniofacial appearance and intelligence. The girl was normal until 3
months of age when she expressed growth retardation with apparently shorter
extremities in relation to the torso. With age, her rhizomelic dwarfism
became increasingly visible, and since completed 15 months of age, when she
started to walk, the disease was complicated with genu varum, lumbar lordosis
and abnormal gait. Beside visibly short forearms, short, broad and ulnar
deviation of the hands, brachydactyly and joint hyperlaxity, the radiographic
picture showed markedly flared metaphyses, small and irregular epiphyses and
poorly formed acetabulum. Conclusion. PSACH is an achondroplasia-like
rhizomelic dwarfism recognized by the absence of abnormality at birth, normal
craniofacial appearance, characteristic epiphyseal and metaphyseal
radiographic finding and joint hyperlaxity.
Ruptured corpus luteum cyst in early pregnancy: A case report
Authors: Vidakovic Snezana , Dokic Milan , Vilendecic Zoran , Djakonovic-Maravic Maja
Published: November 2013

Introduction. Transvaginal sonography and human chorionic gonadotropin (hCG)
testing are cornerstones of modern clinical practice in cases with the
suspected ectopic pregnancy. In unclear cases, if the level of hCG is above
the discriminatory zones, the use of uterine curettage is recommended. There
is an increasing concern that strict observation of the guidelines would
potentially harm otherwise normal early intrauterine pregnancies in certain
cases. Case Outline. A 35-year-old woman was admitted to hospital due to a
severe lower abdominal pain. Based on the positive pregnancy test and
sonographic exams which failed to demonstrate intrauterine pregnancy, the
diagnosis of ectopic pregnancy was presumed. Laparoscopy revealed ruptured
corpus luteum cyst and the diagnosis was confirmed on histopathological
finding. Postoperatively, normal intrauterine gestation was visualized.
Conclusion. Since the diagnosis of early pregnancy and its complications can
be misleading, in unclear cases, we support the expectative ?wait and see?
management consisting of serial hCG testing and repeated ultrasound
examinations. Avoidance of uterine curettage in such unclear cases would
further reduce the possibility of normal early pregnancy interruption.
Chiari pelvic osteotomy in treatment of hip dysplasia
Authors: Slavkovic Nemanja , Vukasinovic Zoran , Apostolovic Milan , Vukomanovic Boris
Published: November 2013

Chiari pelvic osteotomy is a surgical procedure having been performed for
almost sixty years in patients with the insuffcient coverage of the femoral
head. It is most frequently used in young patients with dysplastic acetabular
sockets as a part of developmental hip dysplasia. Even though performance of
the Chiari osteotomy is associated with positive therapeutical results, above
all, its main goal is to delay inevitable degenerative changes. Original
surgical technique has been modified and improved over time. Nevertheless,
the basic idea has remained unchanged - increasing of the femoral head
coverage by medial displacement of the distal part of the pelvis along with
capsular interpositioning. Given the complexity of operation, the
complication percentage is rather low. Chiari pelvic osteotomy has lost its
actuality and importance during this past six decades. The role of Chiari
pelvic osteotomy has been considerably taken over by other more efficient and
more lasting surgical procedures. Nonetheless, Chiari pelvic osteotomy is
still present in modern orthopedic practice, above all as ?salvage?
osteotomy.
Towards a definition of the concept of scene: Communicating on the basis of things that matter
Authors: Kozorog Miha , Stanojevic Dragan
Published: November 2013

The article proceeds from four different but equally important concepts of
scene by the authors John Irwin, Barry Shank, Will Straw, and Keith Harris.
On the basis of these authors? formulations, some essential elements for
conceptualizing scenes are developed - interaction, communication, identity,
and local and supralocal spaces. The four authors? definitions are elaborated
comparatively, and certain problems in the operationalisation of the concept
are discussed. The authors of this article propose their own definition of
the concept of scene, which is based on communication around core or
important ?things?.
The role of cultural and structural factors in the explanation of marginal social position in the USA: Scopes and dilemmas
Authors: Jankovic Stefan
Published: November 2013

The paper gives a historical account of the genesis of marginal social
position explanations in the USA, with special emphasis on the
characteristics, related to the generating of cultural factors in
explanation. In this light, the two fundamental and interrelated concepts are
being indentified - the culture of poverty and the underclass, whose
conceptual genesis, in a causal manner, varies between structural and
cultural grounding. Due the translation of perceived minority behavioural
patterns into the dimensions used for defining the marginal social position,
conceptual validity of the underclass has been heavily disputed. At the same
time, dilemmas created by the implementation of cultural factors constructed
in that way open up broader issues of the relationship between culture and
structure, lines of determination and the possibility of a consistent
explanation of marginal social position.
The internet as interpersonal media: Case of Serbia
Authors: Petrovic Dalibor
Published: November 2013

Bearing in mind that modern technological tools for communication play an
integral role in sustaining of social relationships, the aim of this article
is to determine whether the internet has been replacing face to face (FtF)
contacts in sustaining interpersonal relationships and are there some aspects
of personal networks contact that are handled by interpersonal media of the
internet, email and IM (Instant Messenger). The analysis has been performed
on two levels, first through examination of existing studies on this subject,
and second, trough a survey on communicational use of the internet in Serbia,
conducted in the period 2011-2012. on the sample of 1063 respondents and
through 15 indepth interviews. The obtained results are similar to those from
the vast body of other research, meaning that the internet doesn?t replace
FtF contacts, but also that the internet`s interpersonal media are becoming
more and more important in handling some aspects of personal networks
connections.
A General Model to Monitor the Risk of a Failure to a Means of Transport in Service
Authors: Tomaszek Henryk , Kaleta Ryszard , Zieja Mariusz
Published: November 2013

A model to monitor the risk of a failure/damage (undesirable event) to a means of transport has been outlined in the paper, with findings presented in [2] applied. Destructive processes such as the wear-and-tear, fatigue, and ageing, which arise in the course of the system’s (here: the means of transport) service are most fundamental factors that make health/maintenance status thereof deteriorate. A relationship that describes the probability of an undesirable event (failure) against the system’s service life has been formulated. The rate at which undesirable events may occur, i.e. the failure rate, has also been defined. What results from derived relationships is the statement that failure rates are functions of time the system remains in service. With the permissible risk level assumed, there is a chance to determine the permissible time of failsafe operation.
Pulsacje napięcia wyjściowego jako źródło informacji diagnostycznych o komutatorowych prądnicach prądu stałego
Authors: Gębura Andrzej , Radoń Tomasz
Published: November 2013

Streszczenie

W pracy omówiono wybrane problemy eksploatacyjne komutatorowych prądnic prądu stałego. Omówiono pewne aspekty komutacji oraz wpływ zjawisk fizycznych na kształtowanie się składowej pulsacji napięcia wyjściowego komutatorowych prądnic prądu stałego. Składowa pulsacji jest wypadkową wielu zjawisk fizycznych, w związku z tym - zgodnie z wiedzą zawartą w literaturze specjalistycznej - jest rozdzielana na kilka składowych. Omówiono każdą z nich, systematyzując dostępną w literaturze wiedzę teoretyczną, jednocześnie weryfikując ją z wynikami własnych badań laboratoryjnych. Szczególną uwagę zwrócono na zjawiska komutacji - omówiono objawy nieprawidłowości, możliwości ich wykrywania i przeciwdziałania. Omówiono również pewne zjawiska towarzyszące zmianom w charakterze pulsacji podczas zwarć lub przerw w uzwojeniach w tworniku lub stojanie - wskazano na możliwość diagnozowania tych elementów prądnic za pomocą analizy parametrów składowych pulsacji.
Możliwości diagnozowania systemów nawigacji inercjalnej na bazie analizy wartości błędów Schulera
Authors: Szelmanowski Andrzej
Published: November 2013

Streszczenie

W artykule omówiono błędy czujników inercjalnych wykorzystywanych w systemach odniesienia kursu i pionu AHRS (ang. Attitude and Heading Reference Systems) i systemach nawigacji inercjalnej INS (ang. Inertial Navigation Systems) w zakresie prędkości kątowych i przyspieszeń liniowych. Przedstawiono zależności matematyczne określające ich wpływ na błędy wyliczanych parametrów pilotażowo-nawigacyjnych (takich jak prędkości liniowe i współrzędne pozycji nawigacyjnej) obrazowanych m.in. w nahełmowych systemach celowniczych. Przedstawiono problemy diagnozowania systemów nawigacji inercjalnej, zarówno tych najnowocześniejszych (np. centrali TOTEM-3000 z czujnikami laserowymi, stosowanej na śmigłowcu W-3PL GŁUSZEC), integrowanych na bazie cyfrowej szyny danych MIL-1553B lub ARINC-429, jak i „starszych” rozwiązań konstrukcyjnych (np. układów IKW-1 i IKW-8 stosowanych na samolotach Su-22). Podano metody badań torów przetwarzania sygnałów z czujników inercjalnych oraz wytyczne dla komputerowego systemu oceny stanu technicznego systemów nawigacji inercjalnej z przedłużanym resursem technicznym.
Feasibility to Diagnose Inertial Navigation Systems Through Analysis of Schuler Errors
Authors: Szelmanowski Andrzej
Published: November 2013

The paper is intended to discuss errors in measurements of angular velocity and linear acceleration by means of electronic inertial sensors incorporated into the Attitude and Heading Reference Systems (AHRS) as well as Inertial Navigation Systems (INS). The mathematical equations are found out to establish how these errors affect deviations of flight parameters (such as linear speed and coordinates of the aircraft position indicated by navigation systems) that are calculated from the measurements and imaged e.g. in helmetmounted cueing systems. Some issues related to diagnostics of inertial navigation systems are addressed as well, both the most recent ones (e.g. the TOTEM-3000 central station with laser sensors installed on-board of the W-3PL GŁUSZEC helicopter) integrated via digital data buses MIL-1553B or ARINC-429 as well as more outdated solutions, such as IKW-1 and IKW-8 system used for Su-22 aircrafts. The methods of examination of the data processing paths for signals received from inertial sensors are presented with guidelines for development of the computer system for assessment of technical condition exhibited by systems of inertial navigation with prolonged technical resource.
Diagnostics and Technical Status Monitoring of Electric Fuel Pumps for Aircrafts
Authors: Tokarski Tomasz , Gębura Andrzej
Published: November 2013

The paper outlines selected operational problems associated with electric fuel pumps that are indispensable to build-up positive pressure upstream the plunger pump of turbojet engines. Any failure of that electric pump may lead to suction of air into the plunger pump and eventually the engine flameout. Comparison is made between two electric drives for fuel pumps: a three phase 115/208 VG, 400 Hz AC drive and a 26V DC drive. Attention is paid to serviceability of pumps and capacities of the AFIT to diagnose and monitor technical status of electric fuel pumps.
Vision-Guided Control Algorithms for Micro Aerial Vehicles
Authors: Wijaszka Mirosław
Published: November 2013

This study presents an image analysis method used in the vision guided control system for Micro Air Vehicles (MAVs). The paper describes a hypothetical model of a MAV located in the GPS-denied unknown environment, somewhere indoors. The model keeps moving autonomously following ‘the track’ marked with corners and other feature points recorded with a monocular camera pointed at the far end of a corridor and slightly tilted down at the angle β (20° - 30°). The flight stability and control are provided with an on-board autopilot that maintains zero pitch and roll angles and constant altitude. The image analysis has been based on the real-time computer vision library - OpenCV (Open Source Computer Vision library - http://opencv.willowgarage.com).
Numerical Simulation of Underground Mining Exploitation Influence Upon Terrain Surface / Modelowanie Numeryczne Wpływu Podziemnej Eksploatacji Górniczej Na Powierzchnię Terenu
Authors: Tajduś Krzysztof
Published: November 2013

Underground mining exploitation may result in mining damages to building objects located on a terrain surface. Considering high harmfulness of this phenomenon, the scientists from all over the world have tried to describe impact of underground exploitation on deformations of terrain surface and objects located thereon. The first theories, based on the Gaussian distribution, have emerged in the 1950s and are in use until now. Later on, in connection with development of computational techniques, their availability and numerical methods, a possibility of numerical computations use for forecasting of deformations has emerged. These methods, when suitable numerical models are adopted, enable to include higher number of factors influencing the results being obtained. When constructing numerical model, particular attention should be paid on selection of: appropriate geometry of model, proper constitutive model describing behavior of rock and soil layers, adequate values of rock mass parameters prior to execution of mining exploitation, and after it. The author presented in this article part of these problems, based on own experience.
Study of Ground Response Curve (GRC) Based on a Damage Model / Badanie Krzywej Odpowiedzi Gruntu (Grc) W Oparciu O Model Pękania Skał
Authors: Molladavoodi H.
Published: November 2013

Analysis of stresses and displacements around underground openings is necessary in a wide variety of civil, petroleum and mining engineering problems. In addition, an excavation damaged zone (EDZ) is generally formed around underground openings as a result of high stress magnitudes even in the absence of blasting effects. The rock materials surrounding the underground excavations typically demonstrate nonlinear and irreversible mechanical response in particular under high in situ stress states. The dominant cause of irreversible deformations in brittle rocks is damage process.

One of the most widely used methods in tunnel design is the convergence-confinement method (CCM) for its practical application. The elastic-plastic models are usually used in the convergence-confinement method as a constitutive model for rock behavior. The plastic models used to simulate the rock behavior, do not consider the important issues such as stiffness degradation and softening. Therefore, the use of damage constitutive models in the convergence-confinement method is essential in the design process of rock structures. In this paper, the basic concepts of continuum damage mechanics are outlined. Then a numerical stepwise procedure for a circular tunnel under hydrostatic stress field, with consideration of a damage model for rock mass has been implemented. The ground response curve and radius of excavation damage zone were calculated based on an isotropic damage model. The convergence-confinement method based on damage model can consider the effects of post-peak rock behavior on the ground response curve and excavation damage zone. The analysis of results show the important effect of brittleness parameter on the tunnel wall convergence, ground response curve and excavation damage radius.
Evolution of the Structure and Mechanical Strength of a Coal Particle During Combustion in the Atmosphere of Air and the Mixture of Oxygen and Carbon Dioxide / Ewolucja Struktury Oraz Wytrzymałości Mechanicznej Ziarna Węgla Podczas Spalania W Atmosferze Powietrza Oraz Mieszaninie Tlenu I Dwutlenku Węgla
Authors: Pełka Piotr , Golański Grzegorz , Wieczorek Paweł
Published: November 2013

The research was conducted on the basis of four different types of hard coal and one type of brown coal. There are typical coals commonly used as fuel in Polish CFB boilers. The combustion process was conducted at a temperature of 850°C and the atmosphere of ambient air as well as in the mixture of oxygen and carbon dioxide in different proportions. The research was carried out using specially prepared cubical coal particles with measurements of 15×15mm and also 10×10 mm. The change of the mechanical properties was analyzed based on three parameters, i.e. compression strength, Vickers hardness and fracture toughness. The analysis was supplemented by microscopic images of the surface of the particles using an atomic force microscope. The results obtained clearly indicated the mechanical changes of the coal during its combustion, particularly at the moment of ignition of the char. Moreover, the results correlate very well with the processes of coal comminution that have been described by other authors (Basu, 1999; Chirone et al., 1991) during combustion in the circulating fluidized bed and also explain the sudden change of susceptibility to erosion in the conditions with and without combustion. The measured values can be used as strength parameters in the modelling of the mass loss of coal particles in conditions of circulating fluidized bed combustor that are hard to describe.
Estimating Volume of Roof Fall in the Face of Longwall Mining by Using Numerical Methods / Estymacja Objętości Zawału Stropu W Rejonie Przodka Ścianowego W Oparciu O Metody Numeryczne
Authors: Saeedi Gholamreza , Shahriar Korosh , Rezai Bahram
Published: November 2013

Dilution is one of many challenges confronting professionals in mining and milling, and is perhaps one of the oldest. Longwall mining is one of the mining methods that is often affected by out-of-seam dilution (OSD). In this method, roof falls play a significant role in increasing OSD in the prop-free front of the face area. Thus, estimating the volume of roof fall can be extremely helpful to assess dilution of the run of mine coal without a sampling process. This paper presents the effect of exposed area geometry on potential roof falls using the 2D numerical modelling program FLAC. In this respect, a half-prolate ellipsoid was considered as the low stress level or plasticity zone under yield tension which roof material fall. Since FLAC software does not show roof falls in prop-free front of the face, a series of two-dimensional numerical models are developed using UDEC software. The comparison of the results of two numerical models clearly indicates that volumes of roof fall obtained by means of these methods are in good agreement with each other.
Results from Dealing with Rock and Gas Outburst Prevention in The Czech Republic / Efekty Działań Mających Na Celu Zapobieganie Wybuchom Skał I Gazu, Podejmowanych W Republice Czeskiej
Authors: Hudeček Vlastimil , Zapletal Pavel , Stoniš Milan , Sojka Radislav
Published: November 2013

In the Czech Republic, the prevention of rock and gas outbursts is carried out in the course of driving mine workings in seams and in sandstone and conglomerate beds classified into a category with the highest degree of rock and gas outburst hazard. It is a case of active methods that aim at prevention of rock and gas outbursts by creating a protection zone in front of and in sides of mine workings being driven and passive methods that mitigate the effects of outbursts (Hudeček et al., 2009, 2010).

In this article, authors present recommendations and proposals for changes in rock and gas outburst prevention. These proposed changes should reflect in increased efficiency in coping with this anomalous geomechanical events.
Determination of the Friction Work of a Link Chain Interworking with a Sprocket Drum / Wyznaczenie Pracy Tarcia Łańcucha Ogniwowego We Współdziałaniu Z Bębnem Łańcuchowym
Authors: Sobota Piotr
Published: November 2013

The significant abrasive wear of sprocket drum teeth and seats bottoms is observed during the exploitation of longwall scraper conveyors. For this reason, it is important to determine friction work in sliding conditions of the horizontal link on the tooth seat bottom and on the tooth flank and friction work in the joint of links in the context of such nodes’ abrasive wear. The different construction variants of sprocket drums can be compared by determining friction work in the sliding positions of the horizontal link on the drum. The determination of the losses of the power transmitted is a requisite condition in such situation for determining the efficiency values of chain meshing. The friction work of the friction couple of a sprocket drum - link chain consists of friction work of the horizontal link in the places where it contacts with the seat bottom Ag and the tooth flank Af and friction work in the joints of a horizontal link in the contact place with vertical links: in the front joint Ap and the rear joint At. The article presents dependencies enabling to determine the value of such work for specific geometric relations between the chain and the drum and different friction conditions. The curves of relative friction work and the values of total friction work on the seat bottom, on the tooth flank and in a front and rear joint of links are presented for examples of friction conditions.
Analysis of Methods Used for Assessing Damage Risk of Buildings Under the Influence of Underground Exploitation in the Light of World’s Experience – Part 1 / Analiza Metod Oceny Zagrożenia Obiektów Budowlanych Eksploatacją Podziemną W Świetle Doświadczeń Światowych – Część 1
Authors: Malinowska Agnieszka
Published: November 2013

Methods used for evaluating damage risk of buildings threatened with continuous strains generated by underground exploitation have been addressed in this paper. The main emphasis was put on methods thanks to which the degree of damage of a large group of structural objects could be approximated. The investigations were focused on the origin of those methods, especially the assumed criteria. The final stage of theoretical study was a comparative analysis of presented methods, thanks to which the basic differences between assumptions to those methods as well as the main advantages and disadvantages could be enumerated. Then the damage risk of buildings was evaluated with selected methods. The obtained results were compared with actual data registered in those objects. This enabled the authors to practically evaluate the adaptability of those methods to the underground exploitation conditions in Poland. The first part of the paper is devoted to the presentation of methods and theoretical anaysis of their shortcomings and advantages, followed by the results of analyses performed on actual data.