bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of Short-Term and Long-Term Wave Statistics by Time Domain Simulations Statistics
Authors: Hagen Øistein , Håøy Grue Ida , Birknes-Berg Jørn , Lian Gunnar , Bruserud Kjersti 
Published: October 2017

In the design of new structures and assessment of existing structures, short- and long term statistical distributions of wave height, crest height and wave periods, as well as joint distributions, are important for structural integrity assessment. It is important to model the statistical distributions accurately to calculate wave design criteria and to assess fatigue life.
A detailed study of the wave statistics for an offshore location at the Norwegian Continental Shelf field is carried out. Extensive time domain simulations for the complete scatter diagram of possible sea states are carried out by a second order wave model. Time series of the surface elevation are generated for JONSWAP and Torsethaugen wave spectra, and for several wave spreading models. Statistics for individual wave heights, crest heights and wave periods are established. The simulated results for the short-term statistics are compared with existing short term models that are commonly used, viz. the Forristal, Næss and Rayleigh wave height distributions, and the Forristall 2nd order crest height distribution. Also, parameterized distributions for wave height and for crest height are fitted to the simulated data.
The long-term distributions F(H) and F(C) of all simulated individual wave heights H and crest heights C are determined by weighting the simulations with the long-term probability of occurrence of the sea state. Likewise, the long-term distributions F(Hmax) and F(Cmax) of the maximum simulated individual wave heights Hmax and crest heights Cmax in the sea states are determined.
The design criteria for return periods R = 1, 10, 100 and 10 000 years are determined from the appropriate quantile levels.
The effect of statistical uncertainty is investigated by comparing the confidence intervals for the estimated extreme values results as function of the number N of 3-hour time domain simulations per sea state for 10<N<500.
Structural Reliability Analysis Applied on Steel Ships for Rule Partial Safety Factors Calibration
Authors: Benhamou Alexis , Derbanne Quentin , de Lauzon Jérôme 
Published: October 2017

Ultimate strength assessments in current IACS Common Structural Rules (CSR) are determined by a limited number of constant partial safety factors (PSF). These coefficients are inherited from the previous Common Structural Rules for Oil Tankers, and were determined using a structural reliability analysis (SRA) based on a limited number ship. The authors decided to lead a more comprehensive structural reliability analysis to propose and discuss a new set of rule formulations.
A literature review is carried out in order to determine an extensive database of virtual ships covering the whole range of existing ships with a few representative parameters. SRA is applied for ultimate strength assessment on this database. Uncertainties are modeled by a set of probability distributions applied to each characteristic quantity (still water bending moment, wave bending moment and capacity) and a Second Order Reliability Method (SORM) is used to target the ultimate capacity corresponding to a given failure probability for each ship.
A set of several PSF formulations are then derived from these results using both Working Stress Design (WSD) and Load and Resistance Factor Design (LRFD) approaches. These formulations are then discussed to get an optimum between simplicity and accuracy of the results.
Grounding Damage Estimate Through Acceleration Measurements
Authors: Haag Stan R. , Hoogeland Martijn G. , Vredeveldt Alex W. 
Published: October 2017

Instantaneous insight into the structural damage sustained by a ship running aground, can be of great aid in the decision making following such a disaster. It should be possible to distil the extent of structural damage from acceleration measurement data of the entire vessel. Such measurements could possibly even be done using a simple smartphone.
This paper describes experimental research exploring the detection of plate rupture in a raking damage scenario by merely looking at acceleration measurement data. Drop tower experiments were performed, which reflect a realistic raking damage scenario and also aim to gain better understanding of both friction and failure in such a scenario.
In total four drop tests were performed. Ductile fracture occurred without precedence of necking. A calibration method for a failure criterion, using only one single strain-state, was successfully applied. Separate friction tests showed that static Coulomb friction seems to be a proper model to be applied for the energy dissipation through friction. Moreover, the transition to plate rupture can readily be detected from the experimental acceleration data.
When accurate calibration of both the failure and the friction is performed, it is envisaged that the extent of raking damage can indeed be derived through real time acceleration measurements on board of a vessel.
Application of Frequency Domain Methods for Response Based Analysis of Flexible Risers
Authors: Armstrong C. , Drobyshevski Y. , Chin C. 
Published: October 2017

Response Based Analysis (RBA) is an advanced method for the prediction of long term distributions of critical responses in offshore floating systems. For complex non-linear systems such as flexible risers, RBA requires time domain simulations that form the core data to which probabilistic models are applied. Because RBA requires significantly larger amounts of data than traditional short term analysis approaches, running the required number of simulations in the time domain can quickly become unfeasible if the system’s physics being modelled are exceedingly complex. In addition, flexible risers are complex composite structures with highly dynamic, non-linear responses which further limit the feasibility of application of the RBA process to these systems.
As an alternative, frequency domain solvers, such as that used in the OrcaFlex software, are potential substitutes for portions of datasets due to their processing times being significantly faster than time domain solvers.
A comparison of extreme responses generated by frequency and time domain solvers was performed over the duration of two storms. An upper threshold limit for the frequency domain’s accuracy was found by comparing the differences of the two solver’s responses as the storm progressed; where the differences became too large the threshold limit was set. For environmental conditions smaller than this threshold, the frequency domain solver may provide a quicker method for predicting the riser responses. Conditions that exceed this threshold require full time domain analysis for accurate responses to be generated.
Limitations of the frequency domain solvers include their reduced ability to deal with non-linear mechanics such as bending/curvature responses. As a result, curvature component results from the frequency domain are limited in their direct usability, especially when exposed to more extreme metocean conditions and locations along the riser that are subject to larger curvature (generally where risers are connected to structures with greater stiffness).
Although these limitations exist, the frequency domain solver may still provide reasonable insight into metocean conditions that potentially cause extreme responses.
A method is proposed for the use of both frequency and time domain simulations in the flexible riser flowline RBA process. Screening, filtering and ‘stitching’ methods utilizing the speed of the frequency domain solver are presented in order to compensate for the time domain’s extensive computation times. The proposed method of stitching, when applied to an example storm history, required 39% of the processing time when using only the time domain solver.
Next Generation Hull-Platform “Noah-FPSO Hull” Based on Modular Design and Construction Concept
Authors: Tanaka Shigeru , Takano Kotaro 
Published: October 2017

It is often said that every offshore oil field has its own environmental condition and oil property according to its geographical location. This means that it is very difficult to apply a specific standard design to any FPSO hull, which is usually preferred by many shipyards.
This fact often leads to serious trouble for FPSO hull construction in terms of cost and delivery time.
In order to cope with this problem, Mitsui Engineering and Shipbuilding Co., Ltd. (MES) developed a next generation offshore platform for FPSO, “Mitsui noah-FPSO Hull” (noah : New Offshore Adapted Hull), which consists of unique modular design and construction concept and simple hull form. Structural design is also modularized, i.e. common cross section and frame space, will facilitate to standardized topside module design. In fact, it can be constructed even in multi-shipyards as a consistent cross-platform.
MES has obtained Approval In Principle (AIP) for the noah-FPSO Hull design and concept from American Bureau of Shipping (ABS) and Bureau Veritas (BV).
In this paper, MES introduces these modular concept of the noah-FPSO Hull and its developed technical issues.
Nonlinear Random Wave Time Domain Analysis of Jack-Up Rigs Including Foundation
Authors: Chakrabarti Partha , Somasundaram Deepak Sankar , Chawan Abhijeet 
Published: October 2017

A jack-up rig has to be designed for extreme storm conditions in its elevated mode during operations. Guidelines of ISO 19905-1 [1] and SNAME TR-5-5A [2] for site specific assessment of jack-up rigs explain in detail such analysis and assessment requirements. It is well known that for higher water depths and extreme environment, structural dynamics and spudcan-soil interaction plays a very significant role. The extreme storm response can be determined either by a two-stage deterministic storm analysis procedure using a quasi-static analysis that includes an inertial load set or by a more detailed fully integrated (random wave) dynamic analysis procedure that uses a stochastic analysis. More commonly, however, jack-up rigs are assessed using a two-stage deterministic wave model along with steady wind loads, since this is much simpler. In two-stage deterministic analysis, the first step is the determination of the inertial load set and structural analysis for all the environmental and gravity loads. To include the effects of the spudcan and soil foundation, an initial rotational stiffness or fixity is assumed that depends on the soil type and the preload. Assessment of the foundation is performed thereafter using the yield interaction approach. This is normally an iterative approach to arrive at the right fixity that satisfies the assessment.
The two-stage approach, although simpler could be conservative leading to adverse conclusions for the suitability of a jack-up at a site. As indicated, the other approach is the one-stage approach involving random time domain analysis which is normally not used and reported in the literature probably due to its complexity and difficulty.
The present paper describes random wave time domain analysis of a specific jack-up using a 3D model in 400 ft water depth using USFOS software [3]. This software has the spudcan-soil interaction integrated, to simulate the foundation behavior. In this one-stage analysis, the assessment for the foundation is performed through an iterative approach inside the software using yield and bounding surfaces. Extreme values of some of key responses are compared with traditional deterministic analysis. Benefits and limitations of random wave time domain analysis are explained and quantified. These benefits are sometimes so significant that one-stage analysis may lead to favorable conclusions where the conservative two-stage analysis approach had failed to show the adequacy of the rig. These observations and the overall methodology of analysis used here could be beneficial to any rig’s applicability at a specific site.
Yaw Galloping of a TLWP Platform Under High Speed Currents by Analytical Methods and its Comparison With Experimental Results
Authors: Lamas Francisco , Ramirez Miguel A. M. , Fernandes Antonio Carlos 
Published: October 2017

Flow Induced Motions are always an important subject during both design and operational phases of an offshore platform life. These motions could significantly affect the performance of the platform, including its mooring and oil production systems.
These kind of analyses are performed using basically two different approaches: experimental tests with reduced models and, more recently, with Computational Fluid Dynamics (CFD) dynamic analysis. The main objective of this work is to present a new approach, based on an analytical methodology using static CFD analyses to estimate the response on yaw motions of a Tension Leg Wellhead Platform on one of the several types of motions that can be classified as flow-induced motions, known as galloping.
The first step is to review the equations that govern the yaw motions of an ocean platform when subjected to currents from different angles of attack.
The yaw moment coefficients will be obtained using CFD steady-state analysis, on which the yaw moments will be calculated for several angles of attack, placed around the central angle where the analysis is being carried out. Having the force coefficients plotted against the angle values, we can adjust a polynomial curve around each analysis point in order to evaluate the amplitude of the yaw motion using a limit cycle approach. Other properties of the system which are flow-dependent, such as damping and added mass, will also be estimated using CFD.
The last part of this work consists in comparing the analytical results with experimental results obtained at the LOC/COPPE-UFRJ laboratory facilities.
Bifidobacterium bifidum
Extracellular Sialidase Enhances Adhesion to the Mucosal Surface and Supports Carbohydrate Assimilation
Authors: Nishiyama Keita , Yamamoto Yuji , Sugiyama Makoto , Takaki Takashi , Urashima Tadasu , Fukiya Satoru , Yokota Atsushi , Okada Nobuhiko , Mukai Takao 
Published: October 2017

ABSTRACT

Bifidobacterium
is a natural inhabitant of the human gastrointestinal (GI) tract. We studied the role of the extracellular sialidase (SiaBb2, 835 amino acids [aa]) from
Bifidobacterium bifidum
ATCC 15696 in mucosal surface adhesion and carbohydrate catabolism. Human milk oligosaccharides (HMOs) or porcine mucin oligosaccharides as the sole carbon source enhanced
B. bifidum
growth. This was impaired in a
B. bifidum
ATCC 15696 strain harboring a mutation in the
siabb2
gene. Mutant cells in early to late exponential growth phase also showed decreased adhesion to human epithelial cells and porcine mucin relative to the wild-type strain. These results indicate that SiaBb2 removes sialic acid from HMOs and mucin for metabolic purposes and may promote bifidobacterial adhesion to the mucosal surface. To further characterize SiaBb2-mediated bacterial adhesion, we examined the binding of His-tagged recombinant SiaBb2 peptide to colonic mucins and found that His-SiaBb2 as well as a conserved sialidase domain peptide (aa 187 to 553, His-Sia) bound to porcine mucin and murine colonic sections. A glycoarray assay revealed that His-Sia bound to the α2,6-linked but not to the α2,3-linked sialic acid on sialyloligosaccharide and blood type A antigen [GalNAcα1-3(Fucα1-2)Galβ] at the nonreducing termini of sugar chains. These results suggest that the sialidase domain of SiaBb2 is responsible for this interaction and that the protein recognizes two distinct carbohydrate structures. Thus, SiaBb2 may be involved in
Bifidobacterium
-mucosal surface interactions as well as in the assimilation of a variety of sialylated carbohydrates.

IMPORTANCE
Adhesion to the host mucosal surface and carbohydrate assimilation are important for bifidobacterium colonization and survival in the host gastrointestinal tract. In this study, we investigated the mechanistic basis for
B. bifidum
extracellular sialidase (SiaBb2)-mediated adhesion. SiaBb2 cleaved sialyl-human milk oligosaccharides and mucin glycans to produce oligosaccharides that supported
B. bifidum
growth. Moreover, SiaBb2 enhanced
B. bifidum
adhesion to mucosal surfaces via specific interactions with the α2,6 linkage of sialyloligosaccharide and blood type A antigen on mucin carbohydrates. These findings provide insight into the bifunctional role of SiaBb2 and the adhesion properties of
B. bifidum
strains.
Formation and breaching of two palaeolakes around Leh, Indus valley, during the late Quaternary
Authors: Mujtaba S. A. I. , Lal Ravish , Saini H. S. , Kumar Pawan , Pant N. C. 
Published: October 2017

Abstract

Of the several types of Quaternary deposits formed by glacial, alluvial and mass-wasting processes, with vast climatic and tectonic significance lake deposits stand out prominently in the Indus valley around the town of Leh. We studied a number of palaeolake deposits between the Zinchan–Indus confluence and Shey village and carried out optically stimulated luminescence (OSL) quartz dating of samples from critical sections. Our results indicate that, during the late Quaternary, the Indus River was dammed at least twice in the narrow gorge downstream of Spituk Gompa, forming a reservoir up to 35 km long in which 20–68 m thick sediments were deposited under fluvial and lacustrine environments. During the older phase, the Indus was blocked by debris of moraines/landslides in the narrow zone near the Zinchan–Indus confluence. The resulting lake existed between
c.
125 ± 11 and 87 ± 8 ka during marine isotopic stage (MIS) 5. No evidence of damming material is preserved. Present-day elevations of lake deposits suggest a possible extension of the lake up to Ranbirpura upstream. After the lake breach, the Indus River was again dammed near Phey village by the advancing alluvial fan of the Phyang River. This lake, extending up to Karu, formed at
c.
79 ± ka. The lake existed in this phase during
c.
72–49 ka, during cold-stage MIS-4. The lake was breached after
c.
46 ± 3 ka, however.
Annual cycle of temperature and snowmelt runoff in Satluj River Basin using
in situ
data
Authors: Tiwari Sarita , Kar Sarat C. , Bhatla R. , Bansal R. 
Published: October 2017

Abstract

Melting of snow and ice contributes a large amount of water to the streamflow in the Satluj River. During the winter season, there is low base flow in the river as compared to spring and summer. Temperature is one of the key factors which directly impacts snow and ice melting throughout the year. A substantial amount of snowmelt only occurs when all the snow in a pack reaches isothermal condition. It is therefore very important to know the duration of impact of temperature on snowmelt runoff. Since the Himalayas have very few stations observing hydrological as well as meteorological conditions, it is difficult to validate the snowmelt models and examine changes in small-scale features in river basins of the region. The present study examines the annual cycle and interannual variability of runoff in the Satluj Basin in the western Himalayas and documents the impact of temperature on snowmelt runoff of Satluj River using daily
in situ
data for the period 1982–2005. A multivariate regression model using precipitation and surface temperature has been developed to predict the discharge of Satluj River at a daily scale. It is seen that after every warm phase and cold phase of temperature, the impact persists for around one month and affects the snowmelt runoff during January, February and March at lower- and higher-elevation stations such as Bhakra and Kasol, respectively. The effect of a large fall and rise in temperature is noticed on snowmelt runoff measured at all the discharge stations, while a small temperature change does not affect the observed discharge at all the stations. The remote sensing and reanalysis data are consistent with
in situ
data in the basin, and there is no major change in peak month of discharge or the amplitude during two different periods at Rampur gauge station.
Common TDP1 Polymorphisms in Relation to Survival among Small Cell Lung Cancer Patients: A Multicenter Study from the International Lung Cancer Consortium
Authors: Lohavanichbutr Pawadee , Sakoda Lori C. , Amos Christopher I. , Arnold Susanne M. , Christiani David C. , Davies Michael P.A. , Field John K. , Haura Eric B. , Hung Rayjean J. , Kohno Takashi , Landi Maria Teresa , Liu Geoffrey , Liu Yi , Marcus Michael W. , O'Kane Grainne M. , Schabath Matthew B. , Shiraishi Kouya , Slone Stacey A. , Tardón Adonina , Yang Ping , Yoshida Kazushi , Zhang Ruyang , Zong Xuchen , Goodman Gary E. , Weiss Noel S. , Chen Chu 
Published: October 2017

Abstract
Purpose: DNA topoisomerase inhibitors are commonly used for treating small-cell lung cancer (SCLC). Tyrosyl-DNA phosphodiesterase (TDP1) repairs DNA damage caused by this class of drugs and may therefore influence treatment outcome. In this study, we investigated whether common TDP1 single-nucleotide polymorphisms (SNP) are associated with overall survival among SCLC patients.
Experimental Design: Two TDP1 SNPs (rs942190 and rs2401863) were analyzed in 890 patients from 10 studies in the International Lung Cancer Consortium (ILCCO). The Kaplan–Meier method and Cox regression analyses were used to evaluate genotype associations with overall mortality at 36 months postdiagnosis, adjusting for age, sex, race, and tumor stage.
Results: Patients homozygous for the minor allele (GG) of rs942190 had poorer survival compared with those carrying AA alleles, with a HR of 1.36 [95% confidence interval (CI): 1.08–1.72, P = 0.01), but no association with survival was observed for patients carrying the AG genotype (HR = 1.04, 95% CI, 0.84–1.29, P = 0.72). For rs2401863, patients homozygous for the minor allele (CC) tended to have better survival than patients carrying AA alleles (HR = 0.79; 95% CI, 0.61–1.02, P = 0.07). Results from the Genotype Tissue Expression (GTEx) Project, the Encyclopedia of DNA Elements (ENCODE), and the ePOSSUM web application support the potential function of rs942190.
Conclusions: We found the rs942190 GG genotype to be associated with relatively poor survival among SCLC patients. Further investigation is needed to confirm the result and to determine whether this genotype may be a predictive marker for treatment efficacy of DNA topoisomerase inhibitors. Clin Cancer Res; 23(24); 7550–7. ©2017 AACR.
Lycorine Promotes Autophagy and Apoptosis via TCRP1/Akt/mTOR Axis Inactivation in Human Hepatocellular Carcinoma
Authors: Yu Haiyang , Qiu Yuling , Pang Xu , Li Jian , Wu Song , Yin Shuangshuang , Han Lifeng , Zhang Yi , Jin Chengyun , Gao Xiumei , Hu Wenwei , Wang Tao 
Published: October 2017

Abstract
Lycorine is a multifunctional bioactive compound, and it possesses potential anticancer activities. However, little is known about the underlying mechanism. In this research, we have found that lycorine significantly induces the apoptotic and autophagic capacities of hepatocellular carcinoma (HCC) cells in vitro and in vivo. Treatment with specific autophagy inhibitor (3-methyladenine/Bafilomycin A1) or knockdown of LC-3B/Atg5 by siRNA drastically enhances the apoptotic cell death effect by facilitating the switch from autophagy to apoptosis. Molecular validation mechanistically demonstrates that lycorine-induced apoptosis and autophagy in HCC cells is associated with decreased protein levels of tongue cancer resistance–associated protein 1 (TCRP1), and we further find that inhibition of TCRP1 decreases phosphorylation level of Akt and represses Akt/mTOR signaling. Finally, lycorine-induced apoptosis and autophagy suppress the growth of xenograft hepatocellular tumors without remarkable toxicity. Our results elucidate a novel molecular mechanism whereby lycorine promotes apoptosis and autophagy through the TCRP1/Akt/mTOR pathway in HCC. Our results reveal that lycorine might be a potential therapeutic agent for the treatment of HCC. Mol Cancer Ther; 16(12); 2711–23. ©2017 AACR.