bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of ASP Flooding in a Shallow Oil Reservoir in the Niger Delta
Authors: Hillary Attah , Taiwo Oluwaseun Ayodele , Mamudu Abbas , Olafuyi Olalekan
Published: July 2016

ASP flooding has been most pertinent among the chemical IOR techniques because it has proven most promising depending on the candidate reservoir.

This paper presents the studies of the applicability of ASP flooding in depleted reservoirs in the Niger Delta and reservoirs of similar geologic formation for reasonable incremental oil recovery. The rate of recovery of oil from the reservoir using four different core samples (A, B, T and R) as well as the displacement efficiencies of all four core samples were comparatively analyzed. The fluid flow mechanism of ASP flooding to economically mobilize the residual oil through analyzing production performance was studied. Oil of API gravity of 42.86 degrees and viscosity of 2.5cp and core samples from a Niger delta field were used. 1% wt of NaOH, 0.15% wt of Shell Enordet 0242 and 0.02% wt of Hengfloc 63020 were the alkali, surfactant and polymer used respectively. A sequence of experimental procedure of brine saturation, oil saturation, water flooding and ASP flooding was carried out on the core samples. High pressure core holder, pressure transducer + digital display, digital camera and confining pressure pump were among the instruments used to accomplish the studies.

The results show potential to recover significant additional oil by ASP flood after the 10% recovery factor common to a large number of conventional oil reservoirs in the Niger Delta to date. The reservoir rock shows favourable response to the ASP flooding mechanism, recovering a reasonable percentage of the OOIP which is definitely handy for resolving the declining marginal fields in the Niger delta.
Effect of Temperature on Nigeria Tar Sand Bitumen Viscosity
Authors: Ohenhen I. , Ikiesikimama S. S. , Olafuyi O. A.
Published: July 2016

Production of bitumen from tar sands requires heating the reservoir to several degrees of magnitude to reduce the viscosity of the bitumen. Proper characterization of viscosity property of this fluid is necessary for the designing and optimization of recovery methods. In this work, tar sand samples were collected from different locations in the Ore axis of Ondo state. Bitumen were extracted from the tar sands. The effect of temperature on the viscosity of each sample were measured using an NDJ-8S digital viscometer at temperature ranging from 122-374°F. Viscosity behaviour were different from location to location and they typically reduced as temperature increased. Viscosity measurement varied from 876,000cp – 5,200cp as temperature increased from 122-374°F. Some samples showed higher viscosity profile than other sample. Therefore, higher temperature and energy requirement is needed for the recovery process of these Nigeria Reservoirs.
Comparative Studies of the Performance of ASP Flooding on Core Plugs and Beadspacks
Authors: Taiwo Oluwaseun Ayodele , Mamudu Abbas , Olafuyi Olalekan , Mohammed Ismaila
Published: July 2016

In this work, we present extensive study of Alkaline-Surfactant-Polymer (ASP) flooding in reduction of residual oil saturation in both core plugs and heterogeneous beads-packs. During the ASP flooding of the core plugs, the effectiveness of the ASP flooding EOR technique on a typical Niger Delta reservoir core and other model cores and the determination of the rock properties that most affect the displacement efficiencies of the processes were analyzed. And in the beads-pack flood test, the potential of the ASP slug for oil recovery, the effect of heterogeneity on the oil recovery efficiency of the process and the investigation of the displacement efficiency of Hengfloc in ASP slug for recovery of Niger Delta oil were all analyzed. Finally, the performance in both was comparatively examined. In the ASP Flooding for beadspack, four different beadspack labeled as W, X, Y and Z were used in the experiment. For core flood test, four different core samples termed A1, B1 T1 and R1 used. For each type of porous media, Brine saturation, oil saturation, water flooding and SP flooding were all carried out on different core samples.

The results show that the oil recovery by the imbibition process does not follow a regular pattern. It reveals some complexities in the oil mobilization process and an uneven pattern in the oil recovery due the simulated reservoir heterogeneity. It shows that it's not only the grain size of the reservoir rock but also the arrangement of the grains in the core affect the oil recovery. Water flooding can recover about 70% while ASP flooding can recover between 16 to 19% of the original oil in place from the synthesized heterogeneous beads pack. Bernheimer core gives the best results for ASP EOR flooding operations.
Gas Sales and Aggregation Agreements: Key Risks and Value Drivers
Authors: Adedamola Adegun , Isaac Oluwadiya
Published: July 2016

The domestic natural gas market in Nigeria has undergone significant changes in the past decade. Domestic demand has substantially increased, supply projects are been accelerated and the old amorphous market framework is been gradually organized. The strategic aggregator, the Gas Aggregator Company of Nigeria (GACN) is authorized by government policy to administer the domestic gas supply obligations (DSO) issued for operating exploration and production companies.

GACN matches gas suppliers and potential buyers and also negotiates as part of a tripartite party the Gas Sale Aggregation Agreements (GSAAs). The GSAA template was developed to achieve uniform commercial terms in gas sale transactions across strategic offtake industries. The template has provisions that are protected to achieve uniformity and prevent distortion of the price aggregation process while other provisions are bilateral that allow parties ample room for negotiation. The agreement allocates rights and obligations, risks and roles, rewards and penalties to the parties (gas seller and buyer). GSAAs are long term, multi-million dollar commitments and parties are at the risk of exposure to significant economic losses if they are not aware of the key value drivers. Furthermore, outcome of recent negotiations have necessitated redrafting of hitherto sacrosanct provisions in line with reality.

This paper therefore seeks to highlight the key value drivers, bilateral gaps and contractual provisions that can guarantee proper risk allocation and management amongst parties in the GSAA. The paper further explores generic solution to GSAA activation bottlenecks, outlines operability of certain clauses in the GSAA, provides simple mathematical illustrations of the various interdependent gas supply terms and notes potential areas of conflicts during and after negotiations. An insight into other ancillary agreements to the GSAA is also included. Increased education and understanding of the GSAA framework would minimize commercial disputes, support the growth of the domestic gas market and help mitigate the Nigerian energy challenge.
Experimental Evaluation of Particle Sizing in Drilling Fluid to Minimize Filtrate Losses and Formation Damage
Authors: Anyanwu Chimaroke , Mustapha Unubi Momoh
Published: July 2016

Filtrate losses from drilling mud is a serious issue because it gives rise to several problems during the drilling phase and the production phase of the well. Such problems range from pipe sticking, formation damage to loss of productivity due to phase trapping. Several methods have been proposed and applied to manage this problem but most have been ineffective. Some researchers in the past sought to reduce filtrate invasion by formulating muds capable of forming a seal over the formation pores using bridging agents with properly distributed particle sizes. Others tried to leverage the mud cake permeability by ensuring a high proportion of coarse particles in the mud but only succeeded in controlling invasion to a small extent. The main objective of this work is to reduce filtrate losses and formation damage through investigation of the effect of particle sizing of mica and alumina nano particles on filtrate loss. Four muds were prepared—mud #1: base mud; mud #2: base mud + 60microns mica; mud #3: base fluid + 40microns mica; mud #4: base fluid + alumina nano particles. The names 40 mics mica and 60 mics were derived from the d50s of the 20-200microns mica and 20-325microns mica respectively. Results from the API filtration experiment showed that muds containing large percentage of fine particles, produce filter cakes that have very effective sealing ability. This was evidenced in the respective 30mins fluid loss values obtained for the different muds: base mud (23ml), mud #2 (20ml), mud #3 (17ml), mud #4 (13ml). The alumina nano mud offered the least mud cake permeability, hence the very low amount of filtrate. Field application of this discovery in mud formulation will reduce costs of treating damage and optimize hydrocarbon recovery as phase trapping will become a non issue.
Success Factors for Reservoir Navigation in the Niger Delta Sedimentary Basin: A Case Study of Well-X
Authors: Ndokwu Chidi , Imomoh Victor , Okowi Victor , Onuchukwu Amaka , Idris Maaji
Published: July 2016

The Niger delta sedimentary basin is a depositional complex of Cenozoic-aged sand and shales that extend from an approximate of longitude 3˚ to 9˚ east and latitude 4˚ 30' to 5˚ 20' north. This delta is characterized by progradation, rapid sedimentation, continual loading of sediments and gravity-driven syn-depositional deformations. Hydrocarbon exploration in the Niger delta started in 1937, mainly onshore. Exploration and production now extends offshore.

Given the enormous resources that go into drilling a well, the objective is to get it right the first time (especially when drilling high-angle and horizontal wells with their associated problems of true vertical depth uncertainty and resolution of surface seismic). In drainhole sections, geological uncertainty and production technology pushes geo-steering to the limits. Sometimes, these challenges put forward questions such as: is the reservoir faulted, compartmentalized, thin, undulating or show vertical lithological changes; how far from the roof must the trajectory be; what is the minimum required drain length; and how much dogleg is acceptable?

To achieve success in the reservoir navigation of any well, some success factors must be considered: the drilling strategy, available downhole tool (drilling system and formation evaluation), surface software, personnel and communication protocol. This paper examines these success factors using the example of Well-X. The goal is to bring more understanding to the procedures involved in reservoir navigation, the challenges posed by geology, the factors to consider when planning a modern geo-steering job, the importance of teamwork, the benefits of integrated interpretation and the value communication brings to the entire process.
An Investigation of Dehydration Inefficiencies and Associated Design Challenges in a Gas Dehydration Unit-A Case Study of X Gas Plant
Authors: Ibeh S. U , Chibueze S. E , Abonyi C. L
Published: July 2016

The value and contribution of natural gas in both domestic and economic terrains are extensive. However, its contaminants limits direct application and hence must be treated. Water vapour existing in equilibrium with dry gas is the principal among contaminants. Most corrosion both with acid gases and carbonate salts are traceable to the presence of water. Also the formation of solid icy structures called hydrates constitutes a threat to flow assurance. Removal of water by TEG dehydration trains is not uncommon.

Dehydration inefficiencies such as high water content of the outlet gas and glycol losses could impair operations and considerably reduce profit. Inefficiency in GDU was identified to be due to design factors and operational conditions/scenarios. In the case studied, laboratory analysis of TEG was combined with process simulation results to resolve inconsistencies in design and operational phases. Recommendations for further improvements were also presented.
Challenges, Opportunities and Learnings of Brown Field Re-Entry; A Case Study of XYZ Field in Niger Delta
Authors: Oso Bisong Anthony , Oludewa Awani , Favour Otite , Ebby Ajayi
Published: July 2016

A brown field is an oil or gas asset that has matured to a production plateau or even progressed to a stage of declining production, where significant oil or gas reserves have been produced. Acquisition of brown fields all over the world was on the increase prior to the current volatility of crude oil price in the international market. On acquisition of brown fields, the new investors are always eager to revive the field, explore for more reserves and increase production to maximize profit by seeking to extend the economic producing life of the field using cost-effective, low risk, adaptable technologies. Brown fields' re-entry are usually associated with enormous challenges and opportunities that requires proper solutions to unlock such opportunities to maximize production, break even and maximize profit. This paper focuses on re-entry/re-opening challenges, opportunities, solutions and learnings of XYZ field in Niger delta. Areas to be discussed include; wells selection, estimated vs actual start-up rates, well reactivation, wellheads and facility refurbishment.
Hydrocarbon Utilization Optimization for Sustainable Development in Nigeria: Economic Growth Potential
Authors: Echendu Joseph C. , Iledare Omowunmi O. , Onwuka Emmanuel O. , Ikiensikimama Sunday S.
Published: July 2016

The risks and uncertainties associated with oil price volatility and its global economic impact recently is creating a new thinking in terms of hydrocarbon utilization and energy security. Petroleum rent seeking nations are re-evaluating their micro/macroeconomic policies towards budgeting and producers are restrategizing on the most efficient cost of extraction means for sustained development and production. Ensuing oil geopolitics and regional conflicts are also driving a new energy supply and demand route in meeting global energy demand.

Consequently, this work proffers an energy model that helps to answer the microeconomic implications of oil price volatility on resource based economies. The model incorporates empirical data and estimated aggregate domestic utilization needs to proffer solution on appropriate energy security and sustenance policy to adopt given forecasts of domestic oil and gas production and imports.

The research aim is to analyze the nexus of oil price and economic potentials, especially in Nigeria, with respect to the petroleum value chain. Analysis of the challenges and prospects of hydrocarbon utilization towards economic growth and understanding of the resource base, energy demand and supply mix including development strategy towards energy sustenance are portrayed.

Empirical results reveals that increased domestic utilization of resources gives comparative economic advantage in the balance of trade; eliminate opaque subsidy product loss margin; increase transparent downstream refining; and enormous revenune recapture opportunites approximately 25%, ceteris paribus. Result also shows that Nigeria and Africa at large compete favourably in terms of resource base among the committee of nations. As a result, value creation, economic and pragmatic policy and strategy are plausible imperatives toward energy security and stability.
Comparison of Permeability Plugging Characteristics of Locally Sourced Wellbore Strengthning Materials for Mature Fields Drilling
Authors: Dosunmu Adewale , Anyanwu Chimaroke
Published: July 2016

There is a lot of room for improvement in oil and gas technology among the complex processes in exploration and production. However, the need to prolong the value of mature assets and provide better access to their reserves focuses considerable investment on drilling programs. Pore pressure depletion and its consequent loss circulation problems make up the wellbore instability concerns in mature fields as they translate to cost overruns, Non-Productive Time, Equipment damages. Although loss circulation problems are not new to the industry, repeatedly the need arises to design optimally plugging system to isolate thief zones from the well, while drilling. Wellbore Strengthening materials available to the industry put significant weights on mud costs and usually availability as when needed is not guaranteed. In this work, the performance of a locally sourced Wellbore strengthening material, palm kernel shell (a waste product) is compared with materials used in field operations. The Particle sizing and size distribution as well as permeability filtration tests were conducted to assess and compare the performance of these materials with regards to loss circulation control. Results from these tests showed that permeability plugging characteristics of these local materials compared favorably with those used in field operations.
Managing Subsurface Uncertainty Through Effective Well and Reservoir Management in a Gas Reservoir_X1000YM Reservoir Case Study
Authors: Korubo Waazor , Magnus Nnadi , Suleiman Ahmed , Tunji Bakare , Chima Emelle
Published: July 2016

Understanding the dynamics of a reservoir based on performance and acquired data is key to optimal field development. This is the case for a matured gas reservoir with more than 2Tscf of gas in-place in the Niger Delta.

Based on initial data acquisition during the field development planning, the reservoir was interpreted to be compartmentalized by series of intra-reservoir shales. After four years production, acquired performance data analysis suggests increased communication between reservoir units and lower range of in-place volumes. This is believed to be driven by high mobility of gas and presence of intra reservoir faults that breached the intra-reservoir shales. This updated understanding forms the basis of the re-evaluation of the reservoir.

The depth uncertainty used to generate the low and high case top reservoir structure was revised from 60ft to 33ft (based on residual analysis). The dynamic model was re-calibrated with the updated static model using the Experimental Design (ED) workflow. Performance data from the producing wells were used to calibrate the simulation model to ensure consistent ultimate recoveries estimation. The estimated developed ultimate recovery from the reservoir simulation is comparable with the results from a P/Z analysis and material balance model.

The novelty of this approach is the ability to manage subsurface uncertainty through effective use of well and reservoir data to improve reservoir understanding. Overall, the subsurface uncertainty management strategy ensured collaboration within the sub-surface team, effective use of the installed permanent downhole gauges, and integration of surface and sub-surface data in the update of the simulation model.
Achieving Cost Effective 4D Monitoring in Deep Water Fields
Authors: Effiom Oghogho
Published: July 2016

During times of cost constraints, expensive seismic data acquisition is an activity that is often seen as expendable in a bid to reduce the cost of reservoir management in deepwater offshore fields where such activities can easily add hundreds of millions of dollars to the capital expenditure. It becomes imperative for a field management team to devise innovative ways to aerially monitor their field to manage the subsurface uncertainties that limit the effectiveness of injector wells that support production through water flooding.

One method involves the use of a borehole recording system (DAS-VSP) that can be used to acquire well bore seismic in wells that have fibre optic cables installed. The seismic around the wellbore can be acquired without the use of a rig or a receiver installation on the sea floor. Field studies in Gulf of Mexico indicate that 4D acquired by DAS-VSP are comparable in signal quality to other acquisition methods. Additional advantage is that this system has a low acquisition footprint; hence the surveys can be acquired prior to injection start up in new wells and more frequently in order to determine the efficacy of injection in the short term.

A second method involves the use of i4D, which leverages ocean bottom node technology. It is an intelligent way of acquiring 4D signals in short time stamps (weeks) to get dynamic information with fewer nodes around problem wells. i4D identifies changes due to pressure and water flooding while it is taking place. The cost implication of i4D is an order of magnitude less than full field OBN acquisition because fewer nodes are used in a smaller shot box.

These methods will not totally replace the value of a full field 4D survey, but they can be used to provide the necessary information in-between full field surveys.

Individually, these methods are limited in scope but by combining them, 4D monitoring is achieved cost effectively to close knowledge gaps over time.
Stability of dronabinol capsules when stored frozen, refrigerated, or at room temperature
Authors: Wempe Michael F. , Oldland Alan , Stolpman Nancy , Kiser Tyree H.
Published: July 2016

Purpose

Results of a study to determine the 90-day stability of dronabinol capsules stored under various temperature conditions are reported.

Methods

High-performance liquid chromatography (HPLC) with ultraviolet (UV) detection was used to assess the stability of dronabinol capsules (synthetic delta-9-tetrahydrocannabinol [Δ9-THC] mixed with high-grade sesame oil and other inactive ingredients and encapsulated as soft gelatin capsules) that were frozen, refrigerated, or kept at room temperature for three months. The dronabinol capsules remained in the original foil-sealed blister packs until preparation for HPLC–UV assessment. The primary endpoint was the percentage of the initial Δ9-THC concentration remaining at multiple designated time points. The secondary aim was to perform forced-degradation studies under acidic conditions to demonstrate that the HPLC–UV method used was stability indicating.

Results

The appearance of the dronabinol capsules remained unaltered during frozen, cold, or room-temperature storage. Regardless of storage condition, the percentage of the initial Δ9-THC content remaining was greater than 97% for all evaluated samples at all time points over the three-month study. These experimental data indicate that the product packaging and the sesame oil used to formulate dronabinol capsules efficiently protect Δ9-THC from oxidative degradation to cannabinol; this suggests that pharmacies can store dronabinol capsules in nonrefrigerated automated dispensing systems, with a capsule expiration date of 90 days after removal from the refrigerator.

Conclusion

Dronabinol capsules may be stored at room temperature in their original packaging for up to three months without compromising capsule appearance and with minimal reduction in Δ9-THC concentration.
Quantifying the effects of channel change on the discharge diversion of Jingjiang Three Outlets after the operation of the Three Gorges Dam
Authors: Li Yanyan , Yang Guishan , Li Bing , Wan Rongrong , Duan Weili , He Zheng
Published: July 2016

The Jingjiang Three Outlets (JTO) are the water-sediment connecting channels between the Yangtze River and the Dongting Lake. The discharge diversion of the JTO plays a dominant role in the flood control of the middle–lower Yangtze River, Dongting Lake evolution, and ecological environment. After the operation of the Three Gorges Dam (TGD), the river channels downstream experienced dramatic channel changes. To study the influences of the channel change on the discharge diversion, the authors analyzed the channel changes by water level–discharge rating curves and cross-sectional channel profiles in 1980–2014. Hence, changes in the water level with the same discharge and the decline of discharge diversion at the JTO were noted. Channel incision caused the water level with the same discharge to greatly decrease in the upper Jingjiang River. The water level with the same discharge significantly increased at the JTO as a result of the channel deposition. The channel changes contributed approximately 37.74% and 76.36%, respectively, to the amount and ratio of discharge diversion decreases after the TGD operation. The channel changes serve as the primary factor in facilitating the decrease in the discharge diversion ratio, but not the main factor for the decreased amount of the discharge diversion.
The Evaluation of Implementation the Integrated Farming System Program and the Reality of Increasing Farmers Income in Bali
Authors: Muliarta I Nengah
Published: July 2016

The integrated farming system was an agricultural system that integrates the various agriculture components in a whole unified. It has a positive impact and meets the criteria for the development of sustainable agricultural by optimizing the user of local resources. The one indicator of the success of the integrated farming development was the farmer’s income are increasing. In developing, the program of an integrated farming system in Bali was targeted in 3-4 years for getting a double income. On the one hand, there were many research shows that the implementation of an integrated farming system in Bali has increased the farmer’s income. On the other hand, the job vacancy was created for family farmers. Although, the implementation of the integrated agriculture system has not been optimal. Wherein, the farmers get a benefit in selling their organic fertilizers that were used to reduce the use of chemical fertilizers.
The influence of perceived discrimination, sense of control, self-esteem and multiple discrepancies on the mental health and subjective well-being in Serbian immigrants in Canada
Authors: Vukojevic Vesna , Kuburic Zorica , Damjanovic Aleksandar
Published: July 2016

The study focuses on the mental health and subjective well-being (SWB) of
Serbian immigrants of the first generation in Canada. We wanted to examine if
perceived discrimination, sense of control, self-esteem and perceived
multiple discrepancy affect their mental health and SWB. Our results indicate
that self-esteem and sense of control have a positive effect on mental health
and all aspects of the SWB, while the perceived discrimination and perceived
multiple discrepancy negatively affect SWB and mental health. Self-esteem was
the most salient predictor of mental health, while the perceived multiple
discrepancy was the most salient predictor of life satisfaction of Serbian
immigrants.
Antiepileptic potential of ganaxolone
Authors: Jankovic Slobodan , Lukic Snezana
Published: July 2016

nema
Alveolar bone defect regeneration after bilateral periapical cyst removal with and without use of platelet rich fibrin: A case report
Authors: Vukovic Nemanja , Marjanovic Marjan , Jovicic Bojan , Aleksic Ema , Kalevski Katarina , Borotic Nenad , Pejanovic Djordje , Andjelkovic Marko
Published: July 2016

Introduction. Periapical inflammatory lesions are local bone responses around the apex of a tooth that occur after necrosis of the pulp tissue. The ultimate goal of reconstructive surgical techniques in the treatment of the intra-bone defects is a regeneration of lost bone tissue. The aim of this report was to evaluate clinical and radiographic outcome following the removal of two big, periapical lesions, approximately of the same size, located around maxillary lateral incisors, in the same person at the same time, using two different regenerative approaches. Case report. A healthy, 21-year-old female presented with two large periapical lesions around both upper lateral incisors, and a surgical treatment was indicated. One residual defect (tooth #12) was filled with the mixture of bovinederived hydroxyapatite xenograft and platelet rich fibrin (PRF) gel and covered with PRF membrane, while the other (tooth #22) was filled with bovine-derived hydroxyapatite xenograft only and covered with a resorbable collagen membrane. Clinical and radiographic examinations were performed seven months after the surgery. All clinical and radiographic parameters were significantly improved after the treatment on both sites; however, a newly formed bone around the tooth 12 showed a higher bone density. Conclusion. The use of PRF significantly speeded up filling of the defect compared to bovine- derived hydroxyapatite xenograft.
Effect of comprehensive rehabilitation on the upper limb function in patients after mastectomy
Authors: Zwolińska Jolanta , Homenda Małgorzata , Kwolek Andrzej , Misior Anna
Published: July 2016

Introduction: Breast cancer is the most common cancer in Poland, in Europe and the US. Women after breast cancer treatment suffer from various motor dysfunctions. The most frequent is upper limb dysfunction on the operated side caused by lymphedema and limitations in the shoulder complex mobility. Physical therapy and psychotherapy have a significant beneficial effect on the quality of life of these women. The aim of the study was to assess the effect of comprehensive rehabilitation on the upper limb function and incidence of lymphedema, sensory dysfunctions and pain on the operated side.

Material and methods: The experimental group included 19 patients with diagnosed breast cancer. All of them underwent a standard surgical intervention - radical mastectomy according to Patey’s method followed up by outpatient rehabilitation according to a designed plan. The control group consisted of 16 women who underwent the same treatment but did not take part in the designed rehabilitation program. During the examinations the following parameters were measured: motion range of the shoulder complex, hand-grip strength and occurrence of lymphedema, pain and sensory dysfunctions.

Results: Women in the experimental group improved the upper limb mobility on the operated side and hand-grip strength, and rated lower their level of pain intensity.

Conclusions: The outcomes confirmed the necessity to implement early rehabilitation program as a follow-up treatment for patients after mastectomy. Comprehensive rehabilitation leads to reduced pain intensity and improved upper limb function on the operated side and has a beneficial effect on the general physical fitness of women.
Comprehensive physiotherapy in traumatic brachial plexus injuries conducted in health-resort conditions
Authors: Zgorzalewicz-Stachowiak Małgorzata , Zeńczak Krystyna , Tomczewska Lucyna , Bartkowiak Zuzanna
Published: July 2016

Traumatic brachial plexus palsy is one of the most frequent injuries of the upper limbs in our society. Road-traffic accidents are its most common cause. Due to the clinical picture of brachial plexopathy that can vary to a great extent, its treatment is complicated and long-term. The aim of the study was to evaluate the effectiveness of physiotherapeutic procedures in patients with traumatic brachial plexus injury. A group of 31 patients were investigated during their stay in Szczawno-Jedlina health-resort. The mean age was 43.3. The average time that passed from injury was 34 months. The patients were examined twice: before and after a 3-week motor therapy which consisted of kinesiotherapy after whole-body cryotherapy, magnet therapy, laser therapy, electrotherapy and massage. The following parameters were measured and analyzed: pain intensity on the verbal scale, the range of motion in the shoulder joint, the circumference of the upper limbs and muscle strength on the Lovett scale. The upper limb functional use was evaluated using the Smól and Nowak scale. Additionally, patients’ subjective opinion about the effectiveness of therapy was evaluated. After therapy the intensity of pain decreased and the functional use of the upper limbs improved significantly. The range of motion around the joint increased, but statistically significant results were recorded only in the passive abduction of the arm. There was a slight improvement in muscle strength and circumference of the limbs, but the results were not statistically significant. Most patients claimed that physiotherapy was definitely effective or quite effective. A comprehensive physiotherapy used in patients with traumatic brachial plexus injury in health-resort conditions contributed to pain reduction and improvement in the functional use of the upper limb.
“Dunag 02” dynamic orthosis
Authors: Małachowska-Sobieska Monika , Demczuk-Włodarczyk Ewa , Wronecki Krzysztof , Skolimowski Tadeusz , Kwiatkowski Robert , Skolimowska Beata , Staniszewski Łukasz
Published: July 2016

The “Dunag 02” dynamic orthosis is rehabilitation equipment used to assist the therapy of children with neurological deficits. The elastic tension system of the orthosis enables posture correction and contributes to the compensation control process. Thanks to the functionality (dynamic quality) of the orthosis, the child is not artificially held in uniform, static conditions. The orthosis enables symmetrical stimulation and, by changing biomechanical conditions, prevents the development of irreversible changes in the locomotor system. Using a dynamic orthosis requires an individual approach to each and every patient. It depends on the type of disorder and the current clinical status. The aim of this review is to present the “Dunag 02” dynamic orthosis.
Overall physical fitness in young school-age children with bilateral severe hearing loss
Authors: Bolach Eugeniusz , Bolach Bartosz , Wiernicka Kamila
Published: July 2016

Introduction: Physical fitness is expressed by the function of the motor apparatus, the capacity of organs and systems of the body, as well as motor abilities and life activity. Motor and physical development of children with hearing loss due to a damage of the hearing organ can differ from their hearing peers. The hearing organ dysfunctions can have adverse effect on motricity due to its connections with the nervous system and semicircular canals.

Material and methods: The present study comprised 60 school-age children; the experimental group consisted of 30 girls and boys with hearing loss, while the control group included 30 hearing girls and boys. The children’s age varied between 9 and 11 years; the mean age was 9.75 years. In both groups of children their body mass index was calculated and their overall physical fitness was assessed using the Eurofit - European Physical Fitness Test.

Results: It was found that hearing impairment was mainly connected with the worse sense of balance, lower velocity of upper limb movements and decreased level of agility, i.e. indirectly with worse motor coordination. In addition, it was proved that generally girls manifested a better sense of balance and flexibility, whereas boys showed a higher static and dynamic strength and better agility and endurance.

Conclusions: The study confirmed the hypothesis that children with hearing loss have lower overall physical fitness than their hearing peers. Therefore there is a need to develop motor abilities in children with hearing loss by involving them in deliberate and systematic physical activity.
Objective and parametric methods used in functional classification disabled swimmers
Authors: Uścinowicz Natalia , Seidel Wojciech , Zostawa Paweł , Klich Sebastian
Published: July 2016

The recent Olympic Games in London incited much interest in the competition of disabled athletes. Various people connected with swimming, including coaches and athletes, have speculated about the fairness of competitions of disabled athletes. A constant problem are the subjective methods of classification in disabled sport. Originally, athletes with disabilities were classified according to medical diagnosis. Due to the injustice which still affects the competitors, functional classification was created shortly after. In the present review, the authors show the anomalies in the structure of the classification. The presented discovery led to the suggestion to introduce objective methods, thanks to which it would be no longer necessary to rely on the subjective assessment of the classifier. According to the authors, while using objective methods does not completely rule out the possibility of fraud by disabled athletes in the classification process, it would certainly reduce their incidence. Some of the objective methods useful for the classification of disabled athletes are: posturography, evaluation of the muscle parameters, electrogoniometric assessment, surface electromyography, and analysis of kinematic parameters. These methods have provide objective evaluation in the diagnostic sense but only if they are used in tandem. The authors demonstrate the undeniable benefits of using objective methods. Unfortunately, there are not only advantages of such solution, there also several drawbacks to be found. The conclusion of the article is the statement by the authors that it is right to use objective methods which allow to further the most important rule in sport: fair-play.
The assessment of the body posture and motor abilities of 14-year-old boys and girls
Authors: Walaszek Robert , Kasperczyk Tadeusz , Borowiec Krzysztof
Published: July 2016

Aim of the study: The purpose of this study was to assess the body posture parameters measured with the photogrammetric Moiré’s method, and motor abilities of 14-year-old boys and girls living in Kraków.

Material and methods: The study group consisted of 273 children, including 140 girls and 133 boys, aged 14. Their height and body mass were measured. Their body posture was assessed using the Moiré’s method, as a result of which 14 parameters were described (6 parameters in plane median, 1 in plane transverse and 7 in plane coronal). Motor abilities were assessed using the test of marching balance as well as some trials being part of the battery test EUROFIT.

Results: As far as the body posture, significant differences between the boys and the girls were observed in respect of five parameters assessed with the Moiré’s method thoracic kyphosis angle, elevation of the left inferior angle of scapulae, lowering of the left waist triangle, the difference in height of posterior superior iliac spines, the maximum leftwards deviation of the spine line from the line C7-S1. The statistically significant differences between the boys and the girls were pointed out in terms of the motor abilities with the components of strength, as well as suppleness and flexibility.

Conclusions: Worse body posture of girls and boys aged 14 does not lead to a decrease in physical fitness, therefore it seems that it is necessary to increase the time of physical exercises for these children compared to their peers with better posture.
Posture control after 5 months body balance training in Down syndrom children and youth
Authors: Drzewowska Izabela , Sobera Małgorzata , Sikora Aleksandra
Published: July 2016

Aim of the study: The aim of this study was to verify whether the 5-month training exercises using specific balance exercises of the authorial program improves body balance control in children with Down syndrome (DS).

Materials and methods: The purpose of this study was the verification if the 5-months posture control exercises training by original program relays to posture control in Down syndrome (DS) children and youth. The subjects were 8 DS persons: 4 males and 4 females, aged 13-24. Two 20-seconds consecutive trails of natural bipedal standing position on 2 force platforms AccuSway (AMTI), one under each foot, were performed during research. On the basis of COP (centre of pressure) time series the following indices were computed: range, variability, velocity and area of COP shifts. There were 2 sessions of the research: one just before and the second just after 5-month lasting specific posture control training based on the original exercise program.

Results: The results revealed decreasing of the COP velocity of right lower limb and the COP range in anterior-posterior direction of both lower limbs after the training, comparing to the values from the first research session.

Conclusions: It is concluded that the specific posture control training by the presenting of the original exercises program influenced the posture control improving it and the program can be used in therapy of DS children and youth.
Effect of Corner Modifications on Wind Pressure Characteristics of
Authors: Zhuang Xiang , Zheng Yimin , Dong Xin , Zhao Xin
Published: July 2016

Pressures on a standard high building CAARC and other two same-sized buildings but with chamfered corners and rounded corners are numerical simulated based on the CFD (computational fluid dynamics) software FLUENT. By comparing with the results of the CAARC building from a wind tunnel test, the numerical results are proved to be in good agreements with experimental results. In contrast to the building with sharp corners, the shear layers separated from the chamfered and rounded corners approach the side surface, thus decreasing the drag force due to the reduction of wake width. It is recognized that the flow patterns around the buildings with sharp corners and chamfered corners are a type of complete separation in turbulent flow. While because the round-cornered building is more streamline in turbulent flow, smaller vortex size and thinner wake width decrease the wind pressure on leeward face remarkably. It is concluded that small chamfered corners and rounded corners are very effective to prevent aeroelastic instability for a rectangular building. Among the sharp, chamfered and rounded corners, the corner roundness is the most effective one to decrease the wind pressures.
Stress Evaluation and Fatigue Prediction in a Steel Girder Bridge
Authors: Su Di , Fujino Yozo , Shimada Yuuki , Nagayama Tomonori
Published: July 2016

One of the primary damages of steel girder bridges is the fatigue cracks which suffer from the local stress concentration caused by heavy traffic. In this paper, dynamic stress responses of such a bridge subjected to traffic-induced load is studied to investigate the capability of a FE model in evaluating stress response and extend to predict fatigue life in local members. Good agreement is found in the comparisons between the measurement and the simulation results either for main member or secondary members. By refining the mesh size, the stress concentration effect could be simulated accurately to evaluate the fatigue phenomenon. Furthermore, by the parametric analysis including the vehicle’s load, the running speed, and the road roughness, the results reveal that the quality of the pavement significantly influences the dynamic stress responses of the secondary members and indicates the importance of maintenance of the road pavement.
Shenzhen Bridge #2: An Urban Window
Authors: Dister Vincent , Leclert Louis , Ney Laurent
Published: July 2016

In the heart of the southern Chinese city of Shenzhen, the Futian District is undergoing complete transformation. The construction of a luxury high-rise shopping and residential complex is underway and it includes 5 footbridges which traverse the surrounding expressways and a canopy structure which will protect the central plaza from the sun. Ney & Partners has been encharged of the design of two of these footbridges and the canopy.

"Bridge #2" is a 3.5 m wide and 35 m long footbridge, with a free height of 2.5m. It is covered to protect its occupants from the sun and the rain, but is open along its sides to create a pleasant connection between the buildings, on the axis of the central plaza.

The shape of the footbridge is generated by the extrusion of a simple elliptical shape. The result is a continuous three-dimensional surface which appears to spring from the facades of the two buildings it connects. Two wide openings are created on both sides of the hull. These openings are veritable urban windows which give the structure great transparency and offer users the pleasure of views from inside the footbridge. In view of the dimensions of these openings they are bordered by peripheral plates which enable the connection of a deck hanger system. The bridge takes advantage of its particular geometry to work as a 3D steel shell. In order to reduce the thickness of the steel plates which make up the shell, it is stiffened by a diagonal grid of stiffeners on the internal face. Globally the footbridge works as a 3D bow-string. As it was impossible for the bridge to bear on the buildings, 2 V-shaped columns support the deck, these columns also integrate the rainwater evacuation system.
Periodic Responses of a Taut Cable Attached with a Friction Damper Computed Using Multi-Harmonic Balance Method
Authors: Sun Limin , Chen Lin
Published: July 2016

Friction is an effective and convenient source of energy dissipation for many mechanical and structural systems. For stay cables that are susceptible to multi-mode vibrations due to low intrinsic damping, friction damper is of particular significance because it is able to provide frequency- independent damping. However, the level of damping supplied by a friction damper for a cable has not been fully understood owing to its strong nonlinearity. This study concerns the periodic responses of the cable-friction damper system. The damper is considered using a macro-slip model where the compliance accounts for elasticity of the contact interface and damper support flexibility as well. The periodic response that represents a substantial subset of the dynamic characteristic of the nonlinear system, beside the free decay which is previously focused on in the literature, is solved using multi-harmonic balance method. Subsequently, frequency response of the nonlinear system in the vicinity of cable resonant frequencies are computed through a continuation procedure, based on which the control effect of the friction damper on cable can be appreciated. Eventually, the optimal friction damper parameters can be discussed on the basis of system resonant steady-state responses.
Incorporating Noise Effect in Damage Detection With a Curvature Based Method
Authors: Sun Zhen , Nagayama Tomonori , Fujino Yozo
Published: July 2016

Damage detection is essential for ensuing safety of bridges, and many damage detection methods have been developed in the past few years, which utilizes static or dynamic responses. In this paper, a curvature-based method is proposed for damage detection. In order to verify its reliability and efficacy, laboratory experiment is conducted on a beam specimen, and the measured displacement is used to identify damage with the proposed method. Damage location and severity were both identified. Taking into account measurement noise, two techniques are proposed to reduce effect of measurement noise. The first one uses averaged multiple measurement, and the other one chooses reasonable interval for curvature calculation. They are both verified with the measurements from the laboratory test.
Precast Concrete Segmental Bridge Piers under Ship Impact
Authors: Fang Hai , Zhu Lu , Au Francis T. K.
Published: July 2016

Because of the convenience in construction and quality control, the precast segmental method has been increasingly used not only in bridge decks, but also in bridge piers. For example, this is being used in the bridge piers of the approaches in the Hong Kong-Zhuhai-Macao Bridge currently under construction. As ship collision with bridge piers is one of the most frequent accidents that may lead to bridge failure, attention has been drawn to the safety of precast concrete segmental bridge piers under ship impact.

A numerical study was carried out to analyse the structural behaviour of typical bridge piers under ship impact. Two different designs of bridge pier were considered, namely the cast-in-place reinforced concrete and post-tensioned precast concrete segmental versions. Finite element analyses of the bridge piers under ship impact were conducted taking into account the joints, prestressing tendons, material nonlinearity, etc. The effects of location of ship impact were examined. Results of impact force and the displacement at pier top end were examined. In the light of the numerical results, the design impact loads prescribed by the Chinese bridge design code, Eurocode and AASHTO LRFD Bridge Design Specifications were evaluated.