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As a physiological disorder, chilling injury in kiwifruit may develop when the fruit are stored for long periods at a low storage temperature of 0–1°C. Presence of the disorder, inconsistent with marketing requirements for high-quality fruit, may lead to substantial financial and reputational losses. Thus, early detection or removal of chill-damaged fruit is desirable. This study demonstrates a novel dual-laser scanning system which has potential to be developed into a fast online system for the detection of chilling injury in Actinidia chinensis var. chinensis ‘Zesy002’ kiwifruit. The system consists of two laser modules at 730 and 880 nm wavelengths, a scanning mechanism and two detectors at partial (90°) and full (180°) light transmission. A sample of 231 kiwifruit was used to prove the concept, including 80 sound and 151 chill-damaged fruit of three different severity categories (slight, moderate and severe). A principal component analysis – back propagation neural network was used to classify fruit with 5-fold cross-validation. A comparison was made with standard visible-near infrared (Vis-NIR) interactance spectroscopy used to classify the same fruit using the same modelling algorithm. The dual-laser scanning system showed a slightly higher binary classification accuracy than the Vis-NIR spectroscopy, with an average accuracy of 95% for distinguishing sound and chill-damaged fruit. The classification error rate was 0% for severe damaged fruit. These experimental results demonstrate the potential of this dual-laser scanning system for the detection of chill-damaged fruit. The setup using only two wavelengths, its unique scanning operation and flexible system layout make it practical and attractive for future development for application on high-speed fruit graders.

Elevated intraocular pressure (IOP) is the only modifiable risk factor for primary open-angle glaucoma (POAG). Herein we sought to prioritize a set of previously identified IOP-associated genes using novel and previously published datasets. We identified several genes for future study, including several involved in cytoskeletal/extracellular matrix reorganization, cell adhesion, angiogenesis, and TGF-β signaling. Our differential correlation analysis of IOP-associated genes identified 295 pairs of 201 genes with differential correlation. Pathway analysis identified β-estradiol as the top upstream regulator of these genes with ESR1 mediating 25 interactions. Several genes (i.e., EFEMP1, FOXC1, and SPTBN1) regulated by β-estradiol/ESR1 were highly expressed in non-glaucomatous human trabecular meshwork (TM) or Schlemm’s canal (SC) cells and specifically expressed in TM/SC cell clusters defined by single-cell RNA-sequencing. We confirmed ESR1 gene and protein expression in human TM cells and TM/SC tissue with quantitative real-time PCR and immunofluorescence, respectively. 17β-estradiol was identified in bovine, porcine, and human aqueous humor (AH) using ELISA. In conclusion, we have identified estrogen receptor signaling as a key modulator of several IOP-associated genes. The expression of ESR1 and these IOP-associated genes in TM/SC tissue and the presence of 17β-estradiol in AH supports a role for estrogen signaling in IOP regulation.

Wenchang Field in the South China Sea contains a well-developed fault system, resulting in complex subsurface geology. Imaging the complex fault system plays an important role in hydrocarbon exploration in this area since the fault system forms a link between the source rocks and reservoirs. However, it is difficult to obtain a high-quality depth image of the fault system due to the effects of complex velocity and seismic absorption. Inaccurate depth velocities lead to fault shadows and structure distortions at the target zone. Absorption effects further deteriorate seismic imaging as they cause amplitude attenuation, phase distortion, and resolution reduction. We demonstrate how a combination of high-resolution depth velocity modeling and Q imaging work together to resolve these challenges. This workflow provides a step change in image quality of the complex fault system and targeted source rocks at Wenchang Field, significantly enhancing structure interpretation and reservoir delineation. A couple of commercial discoveries have been made, and several other potential hydrocarbon reservoirs have been identified based on the reprocessed data, which reveal new hydrocarbon potential in this region.

A new broadband wide-azimuth towed-streamer (WATS) survey was acquired to better resolve reservoir compartments in a shallow-water region of the East China Sea. To offset the shortcomings of narrow-azimuth acquisition along the strike direction, two vessels were added side-by-side as additional source vessels to form the WATS acquisition geometry for this survey. This WATS acquisition was much sparser than typical WATS surveys used in deepwater environments due to its one-sided configuration. The combination of sparse acquisition, shallow water, and deep targets set the challenge of how to optimally reveal the potential of side-gun data to improve the final image. Three-dimensional effects and severe aliasing in the crossline direction pose significant challenges for side-gun data processing. We present a comprehensive workflow to resolve these challenges consisting of 3D deghosting, 3D model-based water-layer demultiple, 3D surface-related multiple elimination, and 4D regularization for sparse and shallow-water wide-azimuth data. A tilted orthorhombic velocity model is built with better constraints from the wide-azimuth data, leading to improved fault positioning and imaging. Side-gun data clearly enhance the final target reservoir image and tie better with well data due to improved illumination. A new channel is discovered based on interpretation from the inverted VP/VS, explaining the previous incorrect prediction for one failed well that was drilled into a thinner and shallower channel unconnected to the main reservoir. An analysis of the impact of side-gun data from different offsets and azimuths shows that better azimuthal distribution within middle offset ranges had a more significant impact than far offsets in the final image of this survey. This information provides valuable reference in similar geologic conditions for future acquisition designs.

To facilitate the design of an optical system for detecting internal rot in onions, the light propagation properties in healthy and rotten onions were studied in the 700 to 1000 nm range. The absorption and reduced scattering coefficients of internal onion tissues were measured using a combination of measurements on excised onion slices, using the Inverse-Adding Doubling method (IAD), and light transmittance measurements on extracted onion juice. Standard NIRS transmittance measurements were made on intact onions, revealing a transmission window in the range of 670 to 950 nm. From 700 to 750 nm, more severely rotten onions had lower transmittance, whereas from 850 to 900 nm onions with larger rotten tissue had higher transmittance. A multi-laser light transmittance system was implemented to make accurate measurements for different source-detector positions around intact onions, enabling calculations of attenuation coefficients at 636, 700, 728 and 804 nm. The results showed the onion juice measurements yielded much more accurate absorption coefficients than the IAD method on the onion slices. The attenuation coefficients calculated using accurate optical properties were generally matched with the light transmission characteristics, and were in good agreement (6% on average) with the measured attenuation coefficients for both healthy and rotten onions at 700, 728 and 804 nm.

Deduplication has become essential in disk-based backup systems, but there have been few long-term studies of backup workloads. Most past studies either were of a small static snapshot or covered only a short period that was not representative of how a backup system evolves over time. For this article, we first collected 21 months of data from a shared user file system; 33 users and over 4,000 snapshots are covered. We then analyzed the dataset, examining a variety of essential characteristics across two dimensions: single-node deduplication and cluster deduplication. For single-node deduplication analysis, our primary focus was individual-user data. Despite apparently similar roles and behavior among all of our users, we found significant differences in their deduplication ratios. Moreover, the data that some users share with others had a much higher deduplication ratio than average. For cluster deduplication analysis, we implemented seven published data-routing algorithms and created a detailed comparison of their performance with respect to deduplication ratio, load distribution, and communication overhead. We found that per-file routing achieves a higher deduplication ratio than routing by super-chunk (multiple consecutive chunks), but it also leads to high data skew (imbalance of space usage across nodes). We also found that large chunking sizes are better for cluster deduplication, as they significantly reduce data-routing overhead, while their negative impact on deduplication ratios is small and acceptable. We draw interesting conclusions from both single-node and cluster deduplication analysis and make recommendations for future deduplication systems design.

Living cells act as smart and powerful therapeutic agents within the body. With their ability to sense multiple environmental signals, integrate a wide array of information to make critical decisions, and execute complex tasks, cells exert disease-fighting effects in the body with a precision and sophistication that far exceeds that of the small molecule and protein-based therapeutics that currently dominate modern medicine. The remarkable disease-fighting capabilities of cells can be harnessed for therapeutic use, and cellular therapies are currently being explored for the treatment of conditions ranging from cancer and autoimmunity to spinal cord injury and neurodegenerative disorders. Most cell therapy strategies today rely on the endogenous abilities of cells, but there is great untapped potential in using genetic engineering to tune, optimize, and direct their capabilities. A recent example is the use of genetic modification by researchers in adoptive T cell cancer immunotherapy to generate tumor-targeted T cells with highly potent anti-tumor and proliferative activity to effectively treat chemotherapy-resistant cancer patients. We present several new tools for enhancing the therapeutic capabilities of engineered cells through genetic engineering. First, we describe a synthetic biology approach to orthogonal control over cell migration. Migration is a core capability of many cell types in the body that truly sets cells apart from small molecules and biologics. Specifically, we demonstrate the use of an engineered G protein-coupled receptor to direct the homing and migration of a variety of cell types toward an orthogonal small molecule drug source both in vitro and in a mouse. We also describe ongoing work using the engineered cell migration tool described above to enhance the infiltration of tumors by anti-tumor T cells. Next, we discuss a project exploring the usage of two bacterial pathogen proteins, OspF from Shigella, and YopH from Yersinia Pestis, as reagents to precisely modulate MAPK signaling in yeast and in human T cells. Tools like these hold potential for use in the precise regulation of cellular signaling in therapeutic cells. Finally, I conclude this dissertation with closing remarks on some of the challenges and opportunities ahead for this exciting field of scientific research.

It is not clear if pre-existing anti-virus immunity or multicycle treatment of oncolytic virus (OV) can affect the treatment outcome. This study is to investigate the impact of pre-existing anti Herpes Simplex Virus type-1 (HSV-1) immunity or multicycle OV treatment on the efficacy of VG161, a novel HSV-1 OV armed with IL12, IL15 with its receptor α unit (IL15RA), and a PD-L1 peptide blocker (PDL1B). VG161 has entered phase I trial in Australia and China. Seventy Balb/c mice were divided into 2 groups. One group (35 mice) was subcutaneously immunized by mVG161 (a version of VG161 expresses mouse IL12, human IL15 and PDL1B) on day 1 (5x105 PFU/mouse) followed by a boost on day 7. The other group (35 mice) was non-immunized. On day 7 post-boost, the blood was collected from tail to determine anti-HSV antibody. At the same time, all 70 mice were subcutaneously implanted with CT26 mouse colon cancer cells. Once the tumors reached 100 mm3, 20 mice (10 from each group) were treated with intra-tumoral (IT) injection of either mVG161 at a dose of 5×106 PFU/mouse or Vehicle, once a day for 5 days. Hepatic cancer (HC) PDX tissues were dissected into pieces of 27 mm3 and subcutaneously implanted into humanized mice established by transplantation of 1×104 human CD34 stem cells (HLA matched with PDX). When the tumor reached 100-150 mm3, animals were divided into 4 groups (10 mice/group): vehicle control, positive control (oxaliplatin 5 mg/kg and gemcitabine 100 mg/kg), and 2 groups treated with VG161 at high dose (7.75×106 PFU) or low dose (3.10×105 PFU). The OV treatments were given for 3 cycles with IT injection of VG161 once a day for day 1-5 of each cycle. Tumor, spleen, and peripheral blood mononuclear cells were collected for further analysis. All HSV pre-immunized mice but not naïve mice were HSV-1 antibody positive. By day 19 post-treatment, mVG161 significantly inhibited CT26 tumor growth in both HSV-1 pre-immunized and non-immunized groups, while all control mice were euthanized due to tumor size reached 2000 mm3. Starting from day 27, tumors grew back in non-immunized group but not in pre-immunized group, resulting in a significant difference of tumor size between the 2 groups on day 31 to 39 (p As compared to the negative controls, HC PDX tumors in both treatment groups were significantly smaller with percentage of T/C less than 40% on day 72. The median time for 3-fold increase of tumor size is 41.5 days (95%CI: 32-58) in the vehicle control, 74 days (95%CI: 51-undefined) in high dose group, and not reached in low dose group (p The anti-cancer efficacy of VG161 can be enhanced by pre-immunization of HSV-1 or multicycle administration when the virus is given by IT, suggesting potential clinical benefits of HSV-1 based OV therapy in HSV sero-positive patients and multicycle administration of VG161 for long term maintenance treatment. Citation Format: Jun Ding, Jason Sun, Yana Murad, Erica Lee, Ismael Samudio, William Jia, Ronghua Zhao. Pre-existing HSV-1 Immunity enhances anti-cancer efficacy of a novel immune stimulating oncolytic virus - VG161 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1913.

A novel dual-laser system with laser wavelengths of 730 nm and 850 nm has been developed for the non-destructive detection of chilling injury in Actinidia chinensis var. chinensis ‘Zesy002’ kiwifruit. Chilling injury in kiwifruit is a physiological disorder that may occur during low-temperature storage, with symptoms that are often not evident until the fruit is cut open. This study involved a sample of 162 kiwifruit with differing severity of chilling injury, and a performance comparison between the novel dual-laser system and a standard visible – near infrared (Vis-NIR) interactance spectroscopy approach proven in a prior study. The dual-laser system involved scanning the laser beams across the fruit to generate spatial profiles of light transmission in the fruit. Data analysis with supervised model training, using a support vector machine algorithm, was successfully used to achieve cross-validation prediction accuracies higher than 90 % for distinguishing sound and chilling-injured kiwifruit. The performance was equivalent to that achieved by the Vis-NIR interactance spectroscopy approach, suggesting that the dual-laser method is an alternative and more attractive option because of its easier system layout for high-speed on-line sorting of kiwifruit for chilling injury disorder.

A multispectral imaging (MSI) system, using four discrete wavelengths (685, 850, 904 and 980 nm), has been developed and validated for making spatially resolved reflectance spectroscopy (SRRS) measurements. The primary aim was to evaluate the potential of MSI for high-speed firmness grading of apples. The MSI system validations were made using Intralipid solutions of known concentration and comparing the results against measurements made using a laboratory based inverse adding-doubling method (IAD). The results compared well for scattering properties with both the MSI and IAD measurements in reasonable agreement with known properties. For the absorption properties only the MSI measurements were close. Performance of the MSI system was then compared with a near-infrared spectroscopy (NIRS) system using 100 ‘Royal Gala’ apples ( Malus domestica Borkh.). The apples were measured non-destructively by both the MSI and NIRS systems. Cut apple surfaces were also examined by the MSI system and excised slices of apple tissue were measured using the IAD system. Actual apple firmness was measured by destructive penetrometer. The MSI data analysis involved use of both a phenomenological diffusion model and a heuristic modified Lorentzian model for describing the scattering images at each wavelength. The best MSI results of R = 0.87 and RMSECV = 7.17 N were obtained when the Lorentzian model parameters derived at each wavelength were combined using multiple linear regression (MLR). The NIRS system measurements were still a little better, with a best correlation on R = 0.90 and RMSECV = 6.99 N.

This study presents the development of a spatially resolved transmittance system for detecting internal rots in onions, particularly small and localised rots. A two-wavelength classifier was chosen by considering sensitivities to rots and path-length variations. Near-infrared spectroscopy transmittance measurements were carried out on rot-affected onions, to determine wavelength sensitivities to the presence and severity of rots. Finite Element simulations of light transport in onions were run to determine wavelength sensitivities to source-detector separation. A spatially resolved transmittance system was then developed, using two laser diodes as sources (728 and 805 nm wavelengths) and a single photodiode as detector. The system was experimentally verified, with the measured spatial profiles of the transmittance ratios of the two source wavelengths being sensitive to variation in position and size of internal rots in onions.

We incorporate an explicit neural interlingua into a multilingual encoder-decoder neural machine translation (NMT) architecture. We demonstrate that our model learns a language-independent representation by performing direct zero-shot translation (without using pivot translation), and by using the source sentence embeddings to create an English Yelp review classifier that, through the mediation of the neural interlingua, can also classify French and German reviews. Furthermore, we show that, despite using a smaller number of parameters than a pairwise collection of bilingual NMT models, our approach produces comparable BLEU scores for each language pair in WMT15., Accepted in WMT 18

Offshore pipeline on-bottom roughness analysis is generally performed to understand pipe stress and areas of free spanning. In this paper, the predicted pipeline profiles, by finite element analysis (FEA) modeling, are compared with survey data. Several case studies are presented and parametric effects are assessed. The FEA modeling procedures are presented in this paper along with several project experiences. The pipeline on-bottom roughness analysis is conducted to determine the pipe stress and the associated fatigue damage due to internal pressure and temperature fluctuation and vortex-induced vibration (VIV) of free span sections due to seabed unevenness. The analysis presented in this paper can aid the design of pipeline free spans and mitigation, if required. The parametric effects of higher and lower bound soil stiffness, friction resistance, pipeline bottom tension, external / internal pressure, and content density are considered. The predicted pipeline profiles by FEA modeling are compared with surveyed profiles under several loading conditions. A strong correlation between survey data and finite element analysis (FEA) is achieved. This paper shows that the FEA stress prediction is adequate, and the FEA modeling is suitable as an advanced design tool for pipeline on-bottom roughness assessment and free span behavior analysis. A commonly used mitigation method for VIV fatigue is to install VIV suppression strakes. For overstresses due to pipeline bending effect, the common mitigation methods are to install mechanical supports, use heavy wall pipe and correct the seabed unevenness among others. It is important to reliably predict the pipeline profiles in order to precisely assess the pipeline free span response and to provide guidance to determine a proper free span mitigation strategy. The FEA method can be utilized to realistically simulate the pipeline on-bottom roughness behavior affected by the pipe properties, pipe-soil interaction including penetration and soil friction resistance, the internal and external pressure, product content, temperature profile, and the bottom tension from pipe-lay. An accurately built FEA model can provide a reliable prediction for the pipeline profile, free spanning length and gap under all conditions, which are crucial for the stress and fatigue assessment as well as for the design of free span mitigation.

Improving outcomes for English language learners (ELLs) in secondary science remains an area of high need. The purpose of this study is to investigate bilingual knowledge organization in secondary science classrooms. This study involved thirty-nine bilingual students in three biology classes at a public high school in The Bronx, New York City. Methods included an in-class survey on language use, a science content and English proficiency exam, and bilingual free- recalls. Fourteen students participated in bilingual free-recalls which involved a semi-structured process of oral recall of information learned in science class. Free-recall was conducted in both English and Spanish and analyzed using flow-map methods. Novel methods were developed to quantify and visualize the elaboration and mobilization of ideas shared across languages. It was found that bilingual narratives displayed similar levels of organizational complexity across languages, though English recalls tended to be longer. English proficiency was correlated with narrative complexity in English. There was a high degree of elaboration on concepts shared across languages. Finally, higher Spanish proficiency correlated well with greater overlapping elaboration across languages. These findings are discussed in light of current cognitive theory before presenting the study’s limitations and future directions of research.

In this paper, we present a reprocessing case study that applied the latest processing technologies to improve the seismic imaging inside the granite basement reservoir. The highlight of this effort is the application of the latest Controlled Beam Migration (CBM) technology, and a stack sweep method for updating velocity inside the basement.

Multispectral imaging has been studied in recent years as a means of assessing fruit firmness. Here we report on the development of a static multispectral imaging system (MSI) that was used to validate the potential of the technique for high-speed commercial grading. The system consists of a high-performance CMOS camera, four lasers, electronically controlled shutters and a location control system. It captures four spectral scattering images on the fruit. In this study 100 ‘Royal Gala’ apples have been measured using the static MSI. The MSI measurements were applied on the intact apple and also on a flat surface of internal flesh exposed by removing a thick skin slice. The scattering profiles were fitted with a standard light diffusion model and a heuristic modified Lorentzian model. The results showed that the correlations between penetrometer firmness and model parameters were poor, with the correlation coefficient, R, ranging from 0.4 to 0.8 in the best circumstance of the flat surface measurements. Although multivariate models can improve the correlations, this work suggests that laser scattering information on its own is not sufficient to predict the firmness.

EGFR is frequently mutated and amplified in lung adenocarcinomas sensitive to EGFR inhibitors gefitinib and erlotinib. A secondary mutation, T790M, has been associated with acquired resistance but has not been shown to be sufficient to render EGFR mutant/amplified lung cancers resistant to EGFR inhibitors. We created a model for studying acquired resistance to gefitinib by prolonged exposure of a gefitinib-sensitive lung carcinoma cell line (H3255; EGFR mutated and amplified) to gefitinib in vitro. The resulting resistant cell line acquired a T790M mutation in a small fraction of the amplified alleles that was undetected by direct sequencing and identified only by a highly sensitive HPLC-based technique. In gefitinib-sensitive lung cancer cells with EGFR mutations and amplifications, exogenous introduction of EGFR T790M effectively conferred resistance to gefitinib and continued ErbB-3/PI3K/Akt signaling when in cis to an activating mutation. Moreover, continued activation of PI3K signaling by the PIK3CA oncogenic mutant, p110alpha E545K, was sufficient to abrogate gefitinib-induced apoptosis. These findings suggest that allelic dilution of biologically significant resistance mutations may go undetected by direct sequencing in cancers with amplified oncogenes and that restoration of PI3K activation via either a T790M mutation or other mechanisms can provide resistance to gefitinib.

The high costs associated with hydrocarbon exploration in deepwater have led to an increased business demand for acquisition and processing of high-resolution broadband seismic data. In this paper,...

Summary In this paper, we present the first variable-depth streamer seismic survey offshore China. The objective of the broadband survey is to obtain high resolution and high fidelity seismic data in order to better assess the exploration potential in the region. The acquisition and imaging were done on two separated blocks. The initial result is encouraging, and shows the benefit of broadband data to interpretation.

In this paper we present a case history of multi-azimuth 3D PSDM processing. The datasets show strong HTI as well as VTI anisotropy. We show the processing workflow with emphasis on the construction of an imaging velocity model that correctly represents the orthorhombic anisotropy and short-wavelength velocity variations. The PSDM image is improved over earlier processings.

We report on sub-milliwatt operation of ultra-violet light emitting diodes on sapphire with a peak emission wavelength of 315 nm having quaternary AlInGaN multiple quantum well (MQW) active region. A significant increase in the device-emitted power was achieved using an interdigitated finger geometry design, which reduces the differential resistance and eliminates current crowding. The flip-chip mounting of the diced chips with sapphire substrates improves thermal management and increases the light extraction efficiency from the device active area. For 315 nm emission an optical power as high as 0.23 mW was obtained with 800 mA pulsed pumping current.

Abstract In early 2008, Chevron Thailand and partners contracted CGGVeritas to reprocess forty of their key 3D seismic surveys in the Pattani Basin, Gulf of Thailand, with a combined area of more than 15,000 sq.km. The 40 surveys had been acquired over a period of 26 years (1979 to 2005) with variable acquisition parameters, geometries and azimuths, which resulted in variable amplitude and frequency content and variable fold or sampling density. The benefit of the reprocessing is enormous, but the technical challenges are just as great. In this paper we present some of the technical challenges and solutions in the data processing work. A) Detecting and correcting navigation errors in vintage data. Old surveys tend to have navigation errors. Some errors are not obvious until merging with adjacent surveys. We show how we detect the errors and correct them. B) Data regularization. The data of the 40 surveys were loaded into common grid and offset slots for imaging. A challenge is to bridge any acquisition gaps caused by existing platforms at the time of acquisition. Using advanced interpolation technology, we filled in gaps as wide as 350m. C) Offset-dependent matching of frequency bandwidth, amplitude, time and phase between surveys. We present a workflow that was tested and implemented successfully. D) Fault imaging. We show how fault imaging was improved by incorporating anisotropy in migration. Introduction The Gulf of Thailand Super Cube project in the Pattani Basin was initiated and financed by Chevron Thailand, and carried out by CGGVeritas over a period of 3 years. The project area is shown in Figure 1. The 40 3D seismic surveys cover approximately 15,000 sq. km. Prior to the current project, the data had been processed individually or in small groups for use in interpreting individual field areas. The primary objective of the reprocessing was to produce superior seismic imaging by making use of more advanced processing technology, and by making use of neighbouring surveys as migration aperture input. Specifically, the reprocessing aimed to accurately define the principal faults, and to broaden bandwith for high resolution definition of the reservoirs and near water bottom reflectors for the assessment of drilling hazards. The reprocessing also brought about other benefits, which include: regional consistency with DHI or AVO assessment; continuous regional interpretation and data management; fewer seismic volumes to manage; reducing the number of (redundant) faults and horizons in the database; and conveniently working in multiple field areas without the need to switch seismic workstation projects during an interpretation session. The 40 surveys were acquired over a time span of 26 years (1979 to 2005) with variable acquisition parameters, geometries and azimuths, which resulted in variable amplitude and frequency content and variable fold or sampling density. To merge them seamlessly requires great effort in spectral conditioning, time/phase matching, and AVO characteristics preservation. In addition, for some vintage surveys, essential information such as source signature, accurate navigation and well preserved trace data could be missing or incomplete. The essential information had to be cross-examined and reconstructed to facilitate the reprocessing.

Abstract This paper gives an overview of the latest developments of advanced finite element analysis (FEA) tools that are used for the design of subsea pipelines. It focuses on the deepwater and high pressure / high temperature conditions. The paper demonstrates through the use of FEA, that designs can be undertaken for complex scenarios that were not previously possible. This paper includes three main sections. The first section looks at the ‘global’ analysis of pipelines using a set of highly non-linear finite element programs based on ABAQUS. These programs have been widely utilized for over ten years in oil and gas industry and for hundreds of field developments around the world, in various design stages, from pre-FEED, FEED, to final detail design. The programs are used to undertake the complex design cases, such as lateral buckling, upheaval buckling, pipeline walking; pipe-in-pipe (PIP); thermal buckle management; and pipeline span identification, as well as span stress and collapse screening. The programs have been calibrated against the observed pipeline structural responses in the field. The simulation process covers from installation to operation and can be expanded to pipeline span analysis, route curve stability, and pressure-thermal load fatigue assessment. The second section demonstrates how FEA can be used to undertake ‘local’ modeling of pipelines to address local issues and provide verification and support for a reliable global pipeline design. Pipeline end structure behavior, thermal mitigation buoyancy and soil interaction, thermal mitigation sleeper embedment and installation tolerance, PIP inner pipe lock-in load, field joint stress/strain localization, and free span VIV analysis, are some typical applications. These works can be in component level or represent some local pipeline section. Such detail analyses ultimately relies on the ‘global’ FEA to provide trustworthy loading and boundary conditions. This paper also presents the analysis strategies based on the project experiences, the lessons learned, and future improvement. The presentations include, the route selection versus thermal expansion and global buckling, the FEA modeling process (1-D, 2-D versus 3-D), the pipeline-soil interaction, the selection of mitigation for lateral buckling, and related design issues. The combination of these analysis advancements and extensive project experiences will provide the strong supports on solving the most complex engineering problems presently faced in the offshore industry, and in some cases have allowed significant cost savings to be achieved in the engineering.

Offshore industry is now pushing into the deepwater and starting to face the much higher energy reservoir with high pressure and high temperature. Besides the significant impacts on the material, strength, and reliability of the wellhead, tree, and manifold valve; high Pressure (HP) also leads to thicker pipe wall that increases manufacturing and installation cost. High Temperature (HT) can have much wider impact on operation since the whole subsea system has to be operated over a greater temperature range between the non-producing situations such as installation, and long term shut down, and the maximum production flow. It is more concerned for fact that thicker wall pipe results in much greater thermal load so to make the pipeline strength and tie-in designs more challenging. Burying sections of a HPHT pipeline can provide the advantages of thermal insulation by using the soil cover to retain the cool-down time. Burial can also help to achieve high confidence anchoring and additional resistance to the pipeline axial expansion and walking. Upheaval buckling is a major concern for the buried pipelines because it can generate a high level of strain when happens. Excessive yielding can cause the pipeline to fail prematurely. Partial burial can have less concern although it may complicate the pipeline global buckling behavior and impose challenges on the design and analysis. This paper presents the studies on the upheaval buckling of partially buried pipelines, typical example of an annulus flooded pipe-in-pipe (PIP) configuration. The full-scale FE models were created to simulate the pipeline thermal expansion / upheaval / lateral buckling responses. The pipe-soil interaction (PSI) elements were utilized to model the relationship between the soil resistance (force) and the pipe displacement for the buried sections. The effects of soil cover height, vertical prop size, and soil resistance on the upheaval and lateral buckling response of a partially buried pipeline were investigated. This paper presents the latest techniques, allows an understanding in the global buckling, upheaval or lateral, of partially buried pipeline under the HPHT, and assists the industry to pursue safer but cost effective design.Copyright © 2011 by ASME

A common issue confronted by engineers in analyzing high pressure high temperature (HPHT) pipelines for installation and operating conditions is pipe-soil interaction. For installation, a key concern is whether the soil can generate sufficient resistance to allow the pipeline to be laid on the curve. For operation, a concern is whether the pipeline structural stress can be controlled and mitigated, for the given soil condition, under conditions of thermal expansion and potential global buckling. In both scenarios, pipeline embedment is a critical parameter as it is directly related to soil resistances to the pipeline stability. Previous studies have used experimental, analytical and numerical methods to provide estimates to the pipe embedment during the laying operation. The recently developed Coupled Eulerian-Lagrange (CEL) finite element analysis (FEA) method provides a promising numerical technique in analyzing large-deformation geotechnical problems, such as pipeline embedment analysis. This paper uses this approach, together with currently available embedment solutions, to cross-validate these methods for cohesive soils.Copyright © 2011 by ASME

Thermal expansion and global buckling is a critical design aspect for subsea flowline systems subjected to high pressure and high temperature (HPHT). In the Gulf of Mexico, HPHT oil/gas production is becoming exceedingly common as drilling and production depths extend deeper. Advanced finite element analysis becomes essential for flowline expansion and buckling design which is highly dependent on pipe-soil interaction behavior. For decades, pipe-soil interaction has been the focus of many research studies and joint industry projects. For HPHT flowline systems, thermal mitigation is decisive for safe design. Thermal mitigation acts to control global buckling at designate locations and avoid buckling in unknown locations. Thermal mitigation results in significant cost savings by lowering the welding class besides the buckling locations and increases safety in terms of local buckling, fracture, and fatigue. One widely used thermal mitigation method involves attaching a buoyancy module around a segment of the flowline. In this paper the Coupled Eulerian Langrangian (CEL) finite element (FE) formulation is utilized to simulate the interaction between soil and the thermal mitigation buoyancy module (TMBM). The paper demonstrates the capability of the CEL FE method to simulate large soil deformation without the numerical difficulties that are commonly associated with other numerical formulations e.g. ALE (Arbitrary Lagrangian Eulerian) or more conventional Lagrangian. Initially, a three dimensional (3D), continuum, FE model is used to establish the variation of initial embedment along the length of the buoyancy and adjoining pipe. The study then establishes the lateral displacement/resistance relationships under different levels of contact pressure and soil embedment for a series of buoyancy-soil interaction segments, also using the CEL FE method. Current practice for global pipeline thermal expansion FEA is to utilize the same friction model for both buoyancy-soil interaction and pipe-soil interaction. The obtained buoyancy-soil interaction model from the current study is to be used as input to the global FE model to more precisely simulate flowline lateral buckling behavior. This paper presents a practical application of the current state of the art in modeling large soil deformations in providing an improved approach for modeling buoyancy-soil interactions in the global FEA of pipeline thermal expansion and lateral buckling.Copyright © 2010 by ASME