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Facebook usage affects the mental health and behavior of the students. We should know about this topic because this kind of network may create dependency, with several negative consequences on people’s lives. Facebook may be beneficial, but overusing it may cause problems. Facebook usage may affect one’s mental health and behavior. The use of social media platforms such as Facebook may lead to depression, anxiety, poor sleep quality, and stress, which are often observed in teens and adolescents. This aspect is one of the problems that this study will discuss. This study is a mix of purposive and mixed with quantitative and qualitative research. The research subject of this study was composed of 50 selected Tourism students. First, the data gathered were statistically treated through a descriptive method by using thematic analysis. The process went beyond data gathering; it also involved the analysis and interpretation of the significance of what was described. Thus, the description was often combined with comparison or contrast, involving measurement, classification, analysis, and interpretation. The results of the study showed that Facebook usage affected the mental health of the respondents, with a composite weighted mean of 2.81. Facebook usage affected the behavior, with a composite weighted mean of 2.76. The respondents used a smartphone to access Facebook, with the length of use being 4–5 hours. The extent of Facebook usage affected their mental health and behavior in terms of the extent of Facebook usage in terms of family, which obtained a composite weighted mean of 2.90. In terms of friends, the extent of Facebook usage had a composite weighted mean of 2.90. In terms of school, the extent of Facebook usage had a composite weighted mean of 3.04. The data showed that Facebook usage had a moderate effect on the mental health and behavior of the respondents. This study showed that the students should focus on their subject content, syllabus, projects, activitie

This paper presents some results from the 2011 SHELL tests at the MARINTEK basin. The tests involved towing densely instrumented 38m long flexible cylinders at Reynolds numbers up to 220,000. The main objective it to present the experimental results in a manner that describes the response variability that exists in the measured response data. Despite the fact that VIV is known to be a stochastic process, this is rarely addressed in the literature and currently there is no framework or 'best-practice' in the VIV community that can address statistically non-stationary data. In this paper, the experimental measurements are treated like non-stationary time-series and all statistical quantities which are typically of interest are computed with the use of short duration moving windows (or time-gates). A novel way of plotting and presenting VIV response data for flexible cylinders is introduced that is capable of revealing the inherent variability that exists in the cylinder's response., SHEAR7 Joint Industry Project

Much effort in the past half century has been made to explain the role of damping in the prediction of VIV. Scruton (1965), Griffin et al. (1975), Klamo, et al. (2005) and Govardhan & Williamson (2006) all made significant contributions. None fully characterized the role of damping in governing the response over the full range reduced velocities, which encompass the wake synchronized region. In 2012 Vandiver devised a way to do that with a new damping parameter c*. His results were verified using 2D spring-mounted cylinders in uniform flow. The primary objective of the research described in this paper is to find a c* -like quantity for flexible cylinders, which is capable of organizing response data for flexible cylinders, which may have many modes, be exposed to sheared flows and possess spatially varying properties, such as the coverage of strakes and fairings. Data from a recent high mode VIV model test campaign conducted by SHELL Exploration and Production Company are used to illustrate the application of c* to flexible cylinders. It is shown that, if one accounts for Reynolds number, the response of flexible cylinders with varying strake coverage in the SHELL Tests collapse onto a single curve.

This paper explores the Reynolds number dependence of the Vortex-Induced Vibration (VIV) of flexible marine risers. Emphasis is placed on revealing the trends that exist between the Strouhal number and the Reynolds number and between the dimensionless amplitude (A/D) and Reynolds number. Data is drawn from recent towing tank experiments which used flexible cylinders of three different diameters. The 38m long pipes were exposed to uniform and sheared currents. The Reynolds number range extended from approximately 5,000 to 220,000 — well into the critical regime — with the larger diameter pipes responding in up to the 13th mode and the smaller diameter pipe responding well above the 20th mode. The results and trends from this set of experiments are compared to previous results from laboratory and field experiments., SHEAR7 JIP

This paper presents results obtained as part of the DeepStar Phase 10 program on VIV Factors of Safety. The objective was to develop a general methodology to calibrate Factors of Safety for VIV-induced fatigue and to apply it to partially straked risers. This was achieved using reliability methods, accepted industry VIV prediction software and state-of-the-art model test experiments. Most oil companies use a Factor of Safety of 20 when predicting VIV damage using VIV software tools. There are numerous software tools currently in use in industry to predict VIV damage to straked risers and each of them will have different accuracy, and therefore an intrinsic level of conservatism. Understanding the level of conservatism in different VIV prediction software is therefore critical to determining what Factor of Safety to use. This study benchmarks the latest generation of industry accepted VIV design tools at the time of the study (2011): SHEAR7v4.6, VIVAv6.5 and VIVANAv3.7.24 against high quality VIV data from three separate straked riser experiments. A bias distribution (predicted to measured VIV damage results) is obtained for each software tool as a function of the strake coverage. A novel reliability framework approach is then developed to incorporate all uncertainties associated with VIV fatigue prediction into a limit state function, including variability in met-ocean conditions and variability in the fatigue resistance of the material characterized by a design S-N curve. The limit state function is analyzed using First Order Reliability Methods to develop Factors of Safety for target probabilities of failure. The general method is then applied on two case studies involving an SCR and TTR in Gulf of Mexico loop currents, but it can be easily extended to different locations and riser configurations. The resulting FoS range from about 1 to 15 for most software, and are lower than industry standards for VIV prediction. The FoS do not vary markedly for different riser, DeepStar (Consortium), SHEAR7 JIP

Despite of considerable research activity during the last decades considerable uncertainties still remain in prediction of Vortex Induced Vibrations (VIV) of risers. Model tests of risers subjected to current have been shown to be a useful method for investigation of the VIV behavior of risers with and without suppression devices. In order to get further insight on VIV of risers, an extensive hydrodynamic test program of riser models subjected to vortex-induced vibrations was undertaken during the winter 2010 by Shell Oil Company. The VIV-model test campaign was performed in the MARINTEK Offshore Basin Laboratory. A new test rig was constructed and showed to give good test conditions. Three different 38m long riser models were towed horizontally at different speeds, simulating uniform and linearly varying sheared current. Measurements were made In-Line (IL) and Cross-Flow (CF) of micro bending strains and accelerations along the risers. The test program compromised about 400 tests, which give a rich test material for further studies. In the present paper the test set-up and program are presented and selected results are reported.

This paper addresses a practical problem: “Under which coverage of buoyancy modules, would the Vortex Induced Vibration (VIV) excitation on buoyant segments dominate the response?” This paper explores the excitation competition between bare and buoyant segments of a 38 meter long model riser. The source of data is a recent model test, conducted by SHELL Exploration and Production at the MARINTEK Ocean Basin in Trondheim Norway. A pipe model with five buoyancy configurations was tested. The results of these tests show that (1) the excitation on the bare and buoyant regions could be identified by frequency, because the bare and buoyant regions are associated with two different frequencies due to the different diameters; (2) a new phenomenon was observed; A third frequency in the spectrum is found not to be a multiple of the frequency associated with either bare or buoyancy regions, but the sum of the frequency associated with bare region and twice of the frequency associated with buoyancy region; (3) the contribution of the response at this third frequency to the total amplitude is small; (4) the power dissipated by damping at each excitation frequency is the metric used to determine the winner of excitation competition. For most buoyancy configurations, the excitation on buoyancy regions dominates the VIV response; (5) a formula is proposed to predict the winner of the excitation competition between bare and buoyant segments for a given buoyancy coverage., DeepStar (Consortium), SHEAR7 JIP

Analysis of the data from two Vortex-Induced Vibration (VIV) experiments conducted in the Gulf Stream on a 500-foot-long, 1.43 inches diameter, flexible, tension dominated riser model revealed that the response is predominantly characterized by the presence of traveling waves. It was also observed that the location of the VIV excitation region (power-in) affects the characteristics of the response. The conventional method of modeling the excitation force as a standing wave was found inadequate to predict the location of the peak measured response accurately, especially in the cases where the excitation region is close to a boundary (the ends of the riser model). A modified excitation force model consisting of a combination of standing and traveling wave excitation regions is demonstrated to predict the location of the peak response more accurately. This work presents the idea of modifying the VIV excitation model to include traveling wave characteristics and using mode superposition method for computing the response to this modified force. Examples of the implementation of this method are shown for the two distinct cases of the location of the power-in region — the power-in region adjacent to the boundary and the power-in region away from the boundary. Depending on the location of the power-in region, different proportions of standing and traveling wave excitations are used to yield predicted responses that match the measured response characteristics., DeepStar (Consortium), United States. Office of Naval Research. Ocean Engineering and Marine Systems Program, SHEAR7 JIP

Understanding the level of conservatism in a riser system design for vortex-induced vibration (VIV) fatigue is an important issue for operators. This study represents a demonstration of the calibration methodology to derive consistent values for the Factor of Safety (FoS). The exercise is performed here based on medium scale VIV data and utilizing the most commonly used VIV prediction software by industry. The results emphasize the need for (i) a coherent approach to estimate the FoS to be used and (ii) monitoring/measurement of software improvements as this may increase risk of failure if the influence of such improvements on the FoS is not quantified., DeepStar (Consortium) (DeepStar Phase IX)

A VIV benchmarking study was undertaken using SHEAR7v4.5 against NDP high mode VIV response laboratory data. The purpose of which was to derive an improved set of modeling parameters for partial strake coverage cases whilst not comprising previous accuracy of shear flow bare riser response predictions. Fifty percent (50%) partial strake coverage experimental data was utilized from both uniform and shear flow conditions while bare data was also included in the activity for reference purposes. The results showed that such an activity can derive an improved set of modeling parameters that significantly improve the ability to match experimental results and also highlight where future improvement efforts can be targeted.

Risers are fluid conduits from subsea equipment to surface floating production platforms. The integrity of a riser system plays a very important role in deepwater developments. Riser dynamic analysis is an important part to the system design. This paper investigates riser dynamic analysis using the WKB-Based dynamic stiffness method. This paper first presents a theoretical formulation of the dynamic stiffness method. It then combines the dynamic stiffness method with the WKB theory, which assumes that the coefficients in the differential equation of motion are slowly varying. The WKB-based dynamic stiffness method is derived and a frequency dependent shape function is expressed implicitly. The Wittrick and Williams (W-W) algorithm is further extended to solve eigen value problem for a general non-uniform marine riser. Examples of non-uniform riser are analyzed and the results show the efficiency of this method. In addition, a pipe-in-pipe riser system is analyzed for natural frequencies and mode shapes using the WKB-based dynamic stiffness method with the W-W algorithm. The characteristic of the mode shapes is described for such a riser system., SHEAR7 JIP

Risers are fluid conduits from subsea equipment to surface floating production platforms. The integrity of a riser system plays a very important role in deepwater developments. A top-tensioned riser generally consists of outer casing, inner casing and tubing. The pipes are coupled either through fluids in the annuli or through intermediate guides (centralizers) or through both. This paper investigates the dynamic analysis for such an internally coupled fluid/ riser system. This paper first presents a theoretical formulation for a general riser system coupled with fluids in the annuli and centralizers between pipes. Hydrodynamic forces associated with the viscous fluid in between concentric cylinders are considered. An effective dynamic stiffness matrix method is then developed to evaluate the added mass and damping influence of the fluid on the natural frequencies and the dynamic response of the coupled riser system. A riser example is used to illustrate the fluid coupling impact on the system’s dynamic performance. The coupling through the fluid and centralizers can be optimally designed such that an inner pipe acts as a vibration absorber to the outer casing., SHEAR7 JIP

This paper addresses a practical problem: “What portion of fairing or strake coverage may be lost or damaged, before the operator must take corrective measures?” This paper explores the effect of lost fairings (the exposure length) on Vortex-Induced Vibration (VIV) of flexible cylinders. The source of data is a recent model test, conducted by SHELL Exploration and Production. A 38m long pipe model with varying amounts of fairings was tested. Response as a function of percent exposure length is reported. Unexpected results are also reported: (i) the flexible ribbon fairings used in the experiment did not suppress VIV at speeds above 1 m/s; (ii) Above 1 m/s, a competition was observed between VIV excited in the faired and bare regions of the cylinder, (iii) Unusual traveling wave behavior was documented—waves generated in the bare region periodically changed direction, and exhibited variation in VIV response frequency. The results of these tests showed that (1) the excitation on the bare and faired regions could be identified by frequency, because the faired region exhibited a much lower Strouhal number; (2) as expected, the response to VIV on the bare region increased with exposure length; (3) the response to VIV on the faired region decreased with exposure length., DeepStar (Consortium), SHEAR7 JIP

In this paper we present some results from the recent SHELL tests at the MARINTEK basin. The tests involved towing densely instrumented flexible cylinders at Reynolds numbers up to 220,000. The main objective is to present the experimental results describing the effectiveness of different amounts of strake coverage and to explore the influence of simulated marine growth. The data is presented in terms of CF response amplitudes and rainflow-counted damage rates due to the combined CF and IL bending stresses. All results are compared with the bare cylinder cases which will be used as a reference to determine how effective the strakes are in suppressing VIV and how this effectiveness can be affected by marine growth. The results show that even small bare sections (missing strakes) can lead to significant VIV response. We also observe that moderate amounts of marine growth can quickly negate any suppression coming from the strakes., SHEAR7 JIP

This paper proposes a novel method to identify the power-in regions of long flexible cylinders subjected to vortex-induced vibration (VIV). It also attempts to address a practical problem: “Will a secondary power-in region appear after the primary power-in region is covered with suppression devices?” The source of data is a recent model test on a 38 meter long flexible cylinder, densely instrumented with fiber optic strain gauges and accelerometers. For pipes with partial coverage of suppression devices in uniform flow, the bare region would be expected to be a power-in region and the section with suppression devices is expected to be a power-out region. Experimental data from these types of tests are used to benchmark the proposed power-in zone identification method. The method is then used to identify the power-in zones on a bare cylinder in a sheared flow. This paper also explores the occurrence of secondary power-in regions that may exist, when suppression devices are placed in the primary power-in zone. Secondary power-in regions were observed. Lessons learned from the power-in region identification in sheared flows will be a useful tool for designer/engineers choosing where to place suppression devices., DeepStar (Consortium), SHEAR7 JIP

This paper compares model test data for risers with partial strake coverage to predictions made with the Vortex-Induced Vibration (VIV) prediction program SHEAR7 Versions 4.5 and 4.6. It is shown that new features in Version 4.6 substantially enhance the capability for predicting the VIV response of risers with partial coverage. Experimental data is taken from two large L/D tests: the NDP 38 m long riser tests and the Deepstar-Miami, 500 foot long riser. New methods are described for modeling risers partially covered with helical strakes. Key SHEAR7 parameters are recommended, based on parametric investigations to calibrate the model against the available experimental data. Recommended modeling procedures are described so as to facilitate implementation by SHEAR7 users in their VIV modeling tasks., SHEAR7 JIP

Much effort in the past half century has been made to explain the role of damping in the prediction of VIV. Scruton (1965), Griffin et al. (1975), Klamo, et al. (2005) and Govardhan & Williamson (2006) all made significant contributions. None fully characterized the role of damping in governing the response over the full range reduced velocities, which encompass the wake synchronized region. In 2012 Vandiver devised a way to do that with a new damping parameter c*. His results were verified using 2D spring-mounted cylinders in uniform flow. The primary objective of the research described in this paper is to find a c* -like quantity for flexible cylinders, which is capable of organizing response data for flexible cylinders, which may have many modes, be exposed to sheared flows and possess spatially varying properties, such as the coverage of strakes and fairings. Data from a recent high mode VIV model test campaign conducted by SHELL Exploration and Production Company are used to illustrate the application of c* to flexible cylinders. It is shown that, if one accounts for Reynolds number, the response of flexible cylinders with varying strake coverage in the SHELL Tests collapse onto a single curve.

This paper presents some results from the recent SHELL tests at the MARINTEK basin. The tests involved towing densely instrumented flexible cylinders at Reynolds numbers up to 220,000. The main objective is to present the experimental results describing the effectiveness of different amounts of strake coverage and to explore the influence of simulated marine growth. The data are presented in terms of cross-flow (CF) response amplitudes and rainflow-counted damage rates due to the combined CF and in-line (IL) bending stresses. All the results are compared with the bare cylinder cases which will be used as a reference to determine how effective the strakes are in suppressing vortex-induced vibrations (VIV) and how this effectiveness can be affected by marine growth. The results show that even small bare sections (missing strakes) can lead to significant VIV response. Finally, the tests revealed that even moderate amounts of marine growth can quickly negate any suppression coming from the strakes., SHEAR7 JIP

With Jooyoung Kim, piano.; This recital is presented in partial fulfillment of the requirements for the degree Doctor of Arts in Music (primary emphasis : Music Theory and Composition, secondary emphasis : Saxophone Performance).; Includes a list of upcoming BSU School of Music events (for April 2016)., Series LXX, Number 215., This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about

With Jooyoung Kim, piano.; This recital is presented in partial fulfillment of the requirements for the degree Doctor of Arts in Music (primary emphasis : Music Theory and Composition, secondary emphasis : Saxophone Performance).; Includes a list of upcoming BSU School of Music events (for April 2016)., Series LXX, Number 215., This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about

Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Ocean Engineering., Includes bibliographical references., by J. Kim Vandiver., Ph.D.

Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Ocean Engineering., Includes bibliographical references., by J. Kim Vandiver., Ph.D.

Late Tertiary marine strata of the Waiouru Formation were unconformably deposited on a dissected Late Cretaceous peneplain surface of unusually high relief formed on Torlesse Supergroup greywacke at Waiouru. Central North Island, New Zealand. Waiouru is uniquely located on the southern boundary of the Taupo Volcanic Zone and the northern margin of the Wanganui Basin, an infilled Pliocene basin now subject to Plio-Pleistocene uplift. Two transgressive episodes are identified. The first involved submergence of the peneplain in the Neogene, when Kapitean mudstone was deposited. Then a general marine shallowing occurred around the New Zealand landmass which saw uplift of Waiouru towards the end of the Kapitean Stage, followed by a period of sub-aerial erosion. The second transgressive episode was initiated by subsidence of the Wanganui Basin in the Pliocene, which led to onlap of coarse shallow-water sandstones during the Opoitian Stage. Basement subsidence tended to result in vertical rather than horizontal migration of the shoreline. No evidence has been found for previously recognised eustatic sealevel cycles, due possibly to masking by strong tidal conditions throughout the Opoitian sequence; Waiouru being located on the northern edge of the Pliocene Kuripapango Strait. Eventually, shallow seas supported a faunal population sufficient to produce widespread carbonate skeletal fragments that formed extensive shell limestone beds at the top of the Waiouru Formation. Rapid lateral and vertical changes in the facies are interpreted as due to rapidly changing local depositional conditions. These were caused by the submerging basement initially forming a steep coast with at least two offshore islands. Marine infilling occurred within former incised river valleys 3 km wide and over 300 m in depth. Erosion of local greywacke contributed to the Opoitian sedimentation, as did a granitic source, probably in North-west Nelson, with materials transported from this latter source b

Phorbol esters selectively and reversibly disassemble the contractile apparatus of cultured skeletal muscle as well as inhibit the synthesis of many contractile proteins without inhibiting that of housekeeping proteins. We now demonstrate that phorbol esters reversibly decrease the message levels of at least six myofibrillar genes: myosin heavy chain, myosin light chain 1/3, myosin light chain 2, cardiac and skeletal $\alpha$-actin, and skeletal troponin T. The steady state message levels decrease 50 to 100 fold after 48 hours of exposure to phorbol esters. These decreases can be attributed at least in part to decreases in transcription rates. For at least two genes, cardiac and skeletal $\alpha$-actin, some of the decreases are the result of increased message turnover. In contrast, cardiac troponin T steady state message level does not change and its transcription rate decreases only transiently upon exposure to phorbol esters. Phorbol esters do not decrease the expression of the housekeeping genes, $\alpha$-tubulin, $\beta$-actin, and PA3. Interestingly, phorbol esters do not decrease the steady state message levels of MyoD1, a gene known to be important in the activation of many skeletal muscle specific genes.

An analysis of the motion of a docking platform for a deep submersible is presented. The problem is defined as a docking platform, or cradle, suspended beneath a surface vessel by elastic elements, composed of cable, chain, or similar material. The analysis attempts to predict the motion of the cradle in response to sinusoidal motion of the surface vessel. (Author), Master's thesis.