Добірка наукової літератури з теми "Indirect pressure assessment"

BACKGROUND: Indirect blood pressure measurement is the assessment tool used most frequently in epidemiological studies and hypertension management in the population at large. OBJECTIVE: To review indirect blood pressure measurement within the context of nursing practice. RESULTS: Nurses are not following recommended American Heart Association measurement guidelines. CONCLUSION: A national program of certification in indirect blood pressure measurement, similar to that of basic and advanced cardiac life support, is needed. An initial approach to evaluating present practice is also suggested.

Pulmonary muscle weakness is a symptom of multiple sclerosis (MS) that begins early in the disease process, although it is often not recognized by health-care providers until later stages. Standard pulmonary function tests are not effective in detecting this reduction in pulmonary muscle strength. Maximal inspiratory and expiratory pressures are indirect measures of pulmonary muscle strength that are effective in detecting early changes. Once detected, pulmonary muscle weakness is effectively treated with pressure threshold load inspiratory and expiratory muscle exercises that can be implemented using inexpensive handheld pressure threshold load muscle training devices. These exercises require little time and are effective in patients with any level of disability.

In indirect detecting, the measure value and the measured value are not the same or there is not a determined relationship between them, the measure physical value has to be surmised according to the measured value from statistics principals. Based on traditional and failure detecting method, the assessment methods of two different test conditions are deduced by the whole presumption method, theoretical formula of the confidence intervals, the method of probability and statistics. Moreover, the standard of qualification or unqualification is presented. The examples of engineering have shown that concrete strength is judged qualification with high probability. This method is used not only in test of building structure, especially in the evaluation of earthquake, but also popularizes to other domains, strength detecting for bridges, the pressure vessel, aircraft wing etc.

Abstract The dye-binding methods involving bromcresol green and bromcresol purple may seriously overestimate albumin in serum that has a below-normal albumin/globulin ratio, particularly in nephrotic syndrome hypoalbuminemia. To overcome this problem, we developed a new immunoturbidimetric method for albumin with use of a centrifugal analyzer. Results by this method (y) and by radial immunodiffusion (x) agreed well and yielded the regression equation: y = 0.91x + 1.33 (n = 40, r = 0.96). Compared with laser immunonephelometry, our method is easier and faster (15 min for the overall determination). Thus, the proposed immunoturbidimetric method is particularly suitable for the rapid indirect assessment of oncotic pressure and indirectly for monitoring intravascular body fluids.

The clinical assessment of aerodynamic parameters is important in the physiology and pathophysiology of laryngeal function. Vocal efficiency is among these objective measurements and can be calculated from simultaneous recordings of subglottic pressure, airflow, and sound intensity. Modern techniques allow us to accurately determine sound intensity and airflow. However, methods to determine subglottic pressure are either invasive or laborious. We have evaluated a noninvasive, indirect method to determine subglottic pressure by using a technique based on the interruption of transglottic airflow during phonation. The correlation between the indirectly acquired subglottic pressure measured in the oral cavity by using this technique and the subglottic pressure obtained directly by translaryngeal puncture in human volunteers was highly significant in 35 trials (r = .92, p < .01). This study describes a reliable technique for the noninvasive measurement of subglottic pressure, sound intensity, and airflow.

Various methods for indirect assessment of mean systemic filling pressure (MSFP) produce controversial results compared with MSFP at zero blood flow. We recently reported that the difference between MSFP at zero flow measured by right atrial balloon occlusion (MSFPRAO) and MSFP estimated using inspiratory holds depends on the volume status. We now compare three indirect estimates of MSFP with MSFPRAO in euvolemia, bleeding, and hypervolemia in a model of anesthetized pigs ( n = 9) with intact circulation. MSFP was estimated using instantaneous beat-to-beat venous return during tidal ventilation (MSFPinst_VR), right atrial pressure-flow data pairs at flow nadir during inspiratory holds (MSFPnadir_hold), and a dynamic model analog adapted to pigs (MSFPa). MSFPRAO was underestimated by MSFPnadir_hold and MSFPa in all volume states. Volume status modified the difference between MSFPRAO and all indirect methods (method × volume state interaction, P ≤ 0.020). All methods tracked changes in MSFPRAO concordantly, with the lowest bias seen for MSFPa [bias (confidence interval): −0.4 (−0.7 to −0.0) mmHg]. We conclude that indirect estimates of MSFP are unreliable in this experimental setup. NEW & NOTEWORTHY For indirect estimations of MSFP using inspiratory hold maneuvers, instantaneous beat-to-beat venous return, or a dynamic model analog, the accuracy was affected by the underlying volume state. All methods investigated tracked changes in MSFPRAO concordantly.

Investigation of the coarse alluvial foundation for the Pichi Picun Leufu embankment dam is described and evaluated. Direct and indirect investigation methods are compared and an assessment is made of their relative adequacy in order to gain a realistic understanding of foundation conditions. Indirect methods—dynamic cone penetration testing and shear wave velocity measurement—calibrated by comparative testing in a test embankment, have been found to provide a satisfactory means of evaluating the density of thick alluvial deposits below the water table. Relationships of relative density, penetration resistance, and shear wave velocity are discussed. Dynamic penetration resistance normalized for effective overburden pressure appears to be the more sensitive indicator of changes in material density. Key words: coarse alluvium, relative density, dynamic penetration, shear wave velocity, test embankment, overburden pressure.

Обсяг роботи становить 56 сторінок, міститься 22 ілюстрації, 14 таблиць. Загалом опрацьовано 46 джерел. На сьогодні у ряді досліджень доведено, що довготривале спостереження за значеннями ВЧТ сприяє покращенню постоперативних результатів і запобіганню крововиливам і набрякам. Проте прилади, які наразі використовуються в сучасній медицині для цього, є стаціонарними та великогабаритними і можуть призводити до ряду ускладнень. Очевидно, коли пацієнта вже можна виписувати з лікарні, але ще доволі високий ризик повторних крововиливів та набряків, неможливо здійснювати моніторинг за допомогою цих пристроїв. Існує гостра потреба у бездротовій неінвазивній системі для спостереження за ІКТ для спостереження за темпами реабілітації пацієнтів та запобігання постоперативних ускладнень. Досліджено важливість постійного, довготривалого моніторингу внутрішньочерепного тиску (ВЧТ) і проблеми в цій сфері. На основі визначених складнощів і потреб нейрохірургії розроблено концепцію портативного неінвазивного приладу для опосередкованого вимірювання інтракраніального тиску через яремний. За прототип розглянуто патент «Method and apparatus for noninvasive monitorng of intracranial pressure», в якому було вдосконалено блок вимірювання таким чином, щоб в подальшому пристрій став придатним до портативного неінвазивного моніторингу ВЧТ.
The volume of the work is 56 pages, contains 22 illustrations, 14 tables. A total of 46 sources were processed. Nowadays a number of studies have shown that long-term monitoring of ICP values improves postoperative outcomes and prevents hemorrhage and edema. But the devices currently used in modern medicine for this purpose are stationary, large and can lead to a number of complications. Obviously, when a patient can be discharged from the hospital, but there is still a high risk of recurrent hemorrhage and edema, it is impossible to monitor with these devices. There is an urgent need for a wireless non-invasive ICP monitoring system to monitor the pace of patient rehabilitation and prevent postoperative complications. The importance of continuous, long-term monitoring of intracranial pressure (ICP) and problems in this area have been studied in this thesis. The concept of a portable non-invasive device for indirect measurement of intracranial pressure through the jugular is based on the identified complexities and needs of neurosurgery. The patent "Method and apparatus for noninvasive monitoring of intracranial pressure" was considered as a prototype, in which the measuring unit was improved so that in the future the device became suitable for portable non-invasive monitoring of ICP.

Dramatic climate changes have occurred in the Baltic Sea region caused by changes in orbital movement in the earth–sun system and the melting of the Fennoscandian Ice Sheet. Added to these longer-term changes, changes have occurred at all timescales, caused mainly by variations in large-scale atmospheric pressure systems due to competition between the meandering midlatitude low-pressure systems and high-pressure systems. Here we follow the development of climate science of the Baltic Sea from when observations began in the 18th century to the early 21st century. The question of why the water level is sinking around the Baltic Sea coasts could not be answered until the ideas of postglacial uplift and the thermal history of the earth were better understood in the 19th century and periodic behavior in climate related time series attracted scientific interest. Herring and sardine fishing successes and failures have led to investigations of fishery and climate change and to the realization that fisheries themselves have strongly negative effects on the marine environment, calling for international assessment efforts. Scientists later introduced the concept of regime shifts when interpreting their data, attributing these to various causes. The increasing amount of anoxic deep water in the Baltic Sea and eutrophication have prompted debate about what is natural and what is anthropogenic, and the scientific outcome of these debates now forms the basis of international management efforts to reduce nutrient leakage from land. The observed increase in atmospheric CO2 and its effects on global warming have focused the climate debate on trends and generated a series of international and regional assessments and research programs that have greatly improved our understanding of climate and environmental changes, bolstering the efforts of earth system science, in which both climate and environmental factors are analyzed together.Major achievements of past centuries have included developing and organizing regular observation and monitoring programs. The free availability of data sets has supported the development of more accurate forcing functions for Baltic Sea models and made it possible to better understand and model the Baltic Sea–North Sea system, including the development of coupled land–sea–atmosphere models. Most indirect and direct observations of the climate find great variability and stochastic behavior, so conclusions based on short time series are problematic, leading to qualifications about periodicity, trends, and regime shifts. Starting in the 1980s, systematic research into climate change has considerably improved our understanding of regional warming and multiple threats to the Baltic Sea. Several aspects of regional climate and environmental changes and how they interact are, however, unknown and merit future research.

Prevention of secondary cerebral ischaemic insults is an important management strategy in acute neurological conditions. Monitoring of cerebral perfusion may aid in early identification of ischaemic insults and help with management. A number of tools are available for this purpose. Cerebral perfusion pressure (CPP) is the simplest assessment of cerebral perfusion, but in some cases ischaemia can be present even with a normal CPP. Cerebral blood flow (CBF) imaging, either with computed tomography or magnetic resonance imaging techniques, can provide quantitative regional CBF measurement, but only at a single instance in time. Such studies are valuable in the diagnosis of ischaemia, but are difficult for the management of critically-ill patients. CBF can also be measured within the intensive care unit (ICU), either directly or indirectly through the measurement of cerebral oxygenation. These monitors provide a more continuous measure of CBF, and are more useful in assessing response to treatment. Some of the ICU tools monitor global perfusion and some assess perfusion only in a local area of brain surrounding the monitor. With local monitors, the location of the probe is important for interpretation of the findings.

Abnormalities of diastolic function in the critically ill have been demonstrated to be associated with important intensive care outcomes such as mortality and ventilator weaning failure. The assessment of left ventricular (LV) diastolic function refers requires the analysis of the onset, pattern, and termination of left ventricular filling as determined by the time course and magnitude of the pressure gradient between the left atrium (LA) and LV. Echocardiographic two-dimensional and Doppler findings can provide an indirect assessment of the pattern of LV filling and LA–LV pressure gradients. Current guidelines suggest as a minimum the measurement of LA area and volume, mitral inflow velocities, mitral annular velocities, and tricuspid regurgitant flow velocity (as an indirect assessment of left atrial pressure). Other measurable parameters are also available (e.g. pulmonary venous inflow velocities, isovolumic relaxation time, Colour M-mode mitral propagation velocity) and these may help in identifying and characterizing diastolic dysfunction. Generally, however, they are more difficult to perform. Irrespective of the echocardiographic findings measured and the guidelines followed, there is a paucity of data that validates either the individual measures or the guidelines themselves in the critically ill.

There is now overwhelming evidence that the recent rapid climate change has multiple consequences for birds: their abilities to adapt to climate change is thus a major issue. To understand the evolutionary consequences of climate change, an assessment of how it alters selection pressures is needed. As expected, climate change increases selection for earlier breeding but non-intuitive selection patterns are likely to arise for traits other than phenology. Evolutionary responses to these new selection pressures depend on the evolutionary potential in wild bird populations. Heritability alone is not sufficient to predict responses to selection, as many genetic factors (e.g., genetic correlations, indirect genetic effects) can affect evolutionary trajectories. Altogether, studies investigating the nature of responses to climate change in wild populations (plastic vs microevolutionary responses) are still scarce but suggest that the majority of responses would be due to plasticity.

Decision making processes for developing water resources systems infrastructure and operational policies have ceased to be the exclusive domain of just a few, privileged persons making decisions. Now, more and more groups of the society at both the international and national levels are demanding opportunities to participate in decision making, as well as information about potential consequences of policy decisions. In some countries, public participation in the decision making process has been already sanctioned by law, for example through Environmental Impact Assessment (EIA), public permitting processes, and notice and comment rulemaking procedures. However, in many developing countries, public participation remains unfulfilled despite growing awareness and pressure exercised by various interest groups. To be effective, public participation – either active or passive (through access to knowledge and information concerning the decisions and their impact) – needs appropriate political and legal regulations, in addition to technical means to disseminate objective, complete, and comprehensive information about nature of the decisions to be made, potential alternatives, feasibility of solutions, impact of the potential decisions, etc. Among plethora of the available methods and means for providing the information to the broad circles of the society, the Internet already plays a special and powerful role. This chapter presents the concepts and notions underlying formal approaches to decision making processes, as well as providing a review of the possibilities offered by the Internet to enable access to various sources and types of information that can directly or indirectly support the decision making processes in complex water resources systems.

A contrail (a term introduced for “condensation trail” in 1942 by British pilots) is a visible cloud forming behind aircraft, mainly due to water vapor emissions from the engines. Contrails were first observed behind propeller-driven aircraft in 1915 but form as well from the exhaust of jet engines in cold ambient air (Schumann 1996a). Contrails are visible indicators of cruising aircraft and may impact the Earth's climate. Aircraft exhaust may influence cloud formation either directly by forming contrails or indirectly by causing an aerosol of black carbon soot, volatile particles, and metallic particles which later impact the formation and properties of cirrus clouds in the same air mass at other places. Though the cover by contrails is small compared to the cover by natural cirrus clouds, the potential climatic importance of contrails is being studied intensively. A review of the results obtained so far has been prepared for an assessment on Aviation and the Global Atmosphere (IPCC 1999). It reveals considerable progress in understanding aviation-produced aerosols and cloudiness (Fahey and Schumann 1999). Contrail studies also aid in learning about cirrus formation because contrails are cirrus clouds that form under relatively well defined and reproducible conditions. This chapter reviews some of the progress in understanding contrail formation, occurrence, properties, and radiative impact and identifies some important unanswered questions. Contrail formation can be accurately predicted for given atmospheric temperature and humidity conditions. Contrails form thermodynamically according to the Schmidt-Appleman criterion (Schmidt 1941; Appleman 1953) when the relative humidity (RH) in the plume of exhaust gases mixing with ambient air temporarily reaches or exceeds liquid saturation, so that liquid droplets form on cloud-condensation nuclei (CCN) and soon freeze to ice particles. Measurements have shown that liquid saturation is indeed necessary (see fig. 11.1) and that contrails do not form when the RH exceeds ice saturation (Jensen et al. 1998b; Kärcher et al. 1998a; Schumann et al. 2000). The maximum RH reaches liquid saturation when the ambient temperature is below a threshold temperature of typically -50° to -35°C, depending on ambient pressure and humidity and aircraft properties. This maximum is reached in the young plume (age <0.5 s) closely behind the aircraft.

Indirect combustion noise, generated by the acceleration and distortion of entropy waves through the turbine stages, has been shown to be the dominant noise source of gas turbines at low-frequencies and to impact the thermoacoustic behavior of the combustor. In the present work, indirect combustion noise generation is evaluated in the realistic, fully 3D transonic high-pressure turbine stage MT1 using Large-Eddy Simulations (LES). An analysis of the basic flow and the different turbine noise generation mechanisms is performed for two configurations: one with a steady inflow and a second with a pulsed inlet, where a plane entropy wave train at a given frequency is injected before propagating across the stage generating indirect noise. The noise is evaluated through the Dynamic Mode Decomposition of the flow field. It is compared with previous 2D simulations of a similar stator/rotor configuration, as well as with the compact theory of Cumpsty and Marble. Results show that the upstream propagating entropy noise is reduced due to the choked turbine nozzle guide vane. Downstream acoustic waves are found to be of similar strength to the 2D case, highlighting the potential impact of indirect combustion noise on the overall noise signature of the engine.

Dynamic pressure measurements have been made at a number of power plants using externally mounted strain gages on piping in order to characterize structural loading of upstream piping and pressure vessel components. The pressure fluctuations are derived from the ‘breathing’ mode of the piping therefore this indirect technique must be robust enough to reject the effects of other shell modes and/or bending. Several factors influence the ability to ensure that the breathing mode response can be measured; these factors include strain gage configuration options and data processing methods. The tested strain gage configurations utilized up to eight strain gages per location in an axisymmetric manner to facilitate the handling of any shell mode responses that may exist. Data processing strategies utilizing channel combination and filtering techniques were designed to extract pure breathing mode data for conversion to dynamic pressure. This paper will evaluate the various approaches and identify the most reliable one for plant implementation.

Excavation and Direct Examination of buried piping using conventional non-destructive examination (NDE) has been the traditional inspection approach for decades and remains the only quantitative method for piping evaluations in plants when internal in-line inspection tools cannot be used due to geometry or other constraints. This “difficult to assess” piping presents many challenges, including limited effectiveness of traditional indirect inspection tools, high cost and operational concerns associated with excavations, and the ability to evaluate only a small sampling of a piping system. Many inspection technologies exist for buried pipe assessments; however, no indirect techniques provide the ability to yield quantitative wall loss values suitable for ASME fitness for service calculations beyond what’s exposed in the excavation. An evolving technology, guided wave testing (GWT), has many applications including the ability to provide assessment information beyond the excavation. In this paper, the application of GWT for buried piping inspection will be discussed. We will review: principles behind its operation; the competitive technologies on the market; challenges for the technology; management of data within the Electric Power Research Institute (EPRI) industry standard buried pipe database (BPWorks™ 2.0); trending; case histories showing how GWT can be used to extend the knowledge gained during an excavation by screening adjacent areas for more significant corrosion than observed in the excavated and exposed area; coupling GWT results with other inspection technologies to gain an enhanced interpretation of the overall condition of the line; and how to incorporate this data into an effective structural and/or leakage integrity program as part of the reasonable assurance process.

The integrated assessment of the ecological state of the main rivers of the lake Baikal basin - Verkhnyaya Angara, Tyya, Barguzin, Selenga, Snezhnaya, Bolshaya Rechka, Khilok, Chikoy is based on the assessment of the variability of the basin system under the influence of two groups of indicators: 1) Direct (immediate) impact - the volume of water intake and wastewater discharge, water use and sequential water supply. Assessment of the impact on the state of the above-listed rivers basins from wastewater was performed using the algorithm proposed by A. Korolev et al. (2007). 2) Indirect (mediate) impact - indicators of areal and linear-network impacts on the catchment area. Based on the calculation of the integral anthropogenic pressure on the territory of the above-listed river basins, only the Selenga river experiences an “average” anthropogenic load. On the territory of most river basins, the anthropogenic load is “lowered” and “low”.

The noise originating from the core of an aero-engine is usually difficult to quantify and the knowledge about its generation and propagation is less advanced than that for other engine components. In order to overcome the difficulties associated with dynamic measurements in the crowded core region, dedicated experiments have been set up in order to investigate the processes associated with the generation of noise in the combustor, its propagation through the turbine and the interaction of these two components, which may produce additional — so-called indirect combustion — noise. In the current work, a transonic turbine stage installed at the Laboratorio di Fluidodinamica delle Macchine of the Politechnico di Milano was exposed to acoustic, entropic, and vortical disturbances. The incoming and outgoing sound fields were analyzed in detail by two large arrays of microphones. The mean flow field and the disturbances were carefully mapped by several aerodynamic and thermal probes. The results include transmission and reflection characteristics of the turbine stage, latter one was found to be much lower than usually assumed. The modal decomposition of the acoustic field in the upstream and downstream section show beside the expected rotor-stator interaction modes additional modes. At the frequency of entropy or respectively vorticity excitation, a significant increase of the overall sound power level was observed.

Seismic analysis of tube bundle is of paramount importance in the safety assessment of nuclear installations. These analyses require in particular the calculation of frequency, mode shape and effective mass of the system eigenmodes. As fluid-structure interaction effects can significantly affect dynamic behaviour of immersed structures, the numerical modeling of the tube bundle has to take into account FSI. A complete modeling of heat exchangers (including pressure vessel, tubes and fluid) is not accessible to the engineer for industrial design studies. In the past decades, homogenization methods have been studies and developed in order to model tubes and fluid through an equivalent continuous media, thus avoiding the tedious task to mesh all structure and fluid sub-domains within the tube bundle. Few of these methods have nonetheless been implemented in industrial finite element codes. In previous papers (Sigrist & Broc, Pressure Vessel and Piping, Vancouver, July 2006), a homogenization method has been developed and applied to an industrial case for the modal analysis of a nuclear rector with internal structures and coupling effects modeling. The present paper aims at investigating the application of the proposed method for the dynamic analysis of tube bundle. The homogenization method is compared with direct and indirect fluid-structure coupled methods for the calculation of eigenmode frequencies, shapes and modal masses.

Gibson Energy performed a liquid pipeline spill analysis on the approximately 1 kilometre long 168.3 mm Crude Oil pipeline near the Edmonton South Terminal. This pipeline crosses a sensitive tributary that drains into the North Saskatchewan River. The pipeline is currently not in operation, however is locked in with product. This spill analysis is unique in that the pipeline is under minimal pressure with no appreciable flow rate. As a result, the objective of this analysis was to illustrate the length of time required to perform drain down at various locations along the pipeline. The Spill Analysis consisted of modeling a potential liquid release scenario for overland flow modeling of a liquid release and reports both direct and indirect High Consequence Area (HCA) impacts. Additionally, data showing spill plume extents, final volumes and other GIS data was generated for map generation. This presentation will discuss the methods, data, parameters, and results of this analysis and the next steps in providing regulators sufficient information for a comprehensive contingency plan of the Edmonton terminal.

Managing the integrity of pipeline system is the primary goal of every pipeline operator. To ensure the integrity of pipeline system, its health assessment is very important and critical for ensuring safety of environment, human resources and its assets. In long term, managing pipeline integrity is an investment to asset protection which ultimately results in cost saving. Typically, the health assessment to managing the integrity of pipeline system is a function of operational experience and corporate philosophy. There is no single approach that can provide the best solution for all pipeline system. Only a comprehensive, systematic and integrated integrity management program provides the means to improve the safety of pipeline systems. Such programme provides the information for an operator to effectively allocate resources for appropriate prevention, detection and mitigation activities that will result in improved safety and a reduction in the number of incidents. Presently GAIL (INDIA) LTD. is operating & maintaining approximately 10,000Kms of natural gas/RLNG/LPG pipeline and HVJ Pipeline is the largest pipeline network of India which transports more than 50% of total gas being consumed in this country. HVJ pipeline system consists of more than 4500 Kms of pipeline having diameter range from 04” to 48”, which consist of piggable as well as non-piggable pipeline. Though, lengthwise non-piggable pipeline is very less but their importance cannot be ignored in to the totality because of their critical nature. Typically, pipeline with small length & connected to dispatch terminal are non-piggable and these pipelines are used to feed the gas to the consumer. Today pipeline industries are having three different types of inspection techniques available for inspection of the pipeline. 1. Inline inspection 2. Hydrostatic pressure testing 3. Direct assessment (DA) Inline inspection is possible only for piggable pipeline i.e. pipeline with facilities of pig launching & receiving and hydrostatic pressure testing is not possible for the pipeline under continuous operation. Thus we are left with direct assessment method to assess health of the non-piggable pipelines. Basically, direct assessment is a structured multi-step evaluation method to examine and identify the potential problem areas relating to internal corrosion, external corrosion, and stress corrosion cracking using ICDA (Internal Corrosion Direct Assessment), ECDA (External Corrosion Direct Assessment) and SCCDA (Stress Corrosion Direct Assessment). All the above DA is four steps iterative method & consist of following steps; a. Pre assessment b. Indirect assessment c. Direct assessment d. Post assessment Considering the importance of non-piggable pipeline, integrity assessment of following non piggable pipeline has done through direct assessment method. 1. 30 inch dia pipeline of length 0.6 km and handling 18.4 MMSCMD of natural gas 2. 18 inch dia pipeline of length 3.65 km and handling 4.0 MMSCMD of natural gas 3. 12 inch dia pipeline of length 2.08 km and handling 3.4 MMSCMD of natural gas In addition to ICDA, ECDA & SCCDA, Long Range Ultrasonic Thickness (LRUT-a guided wave technology) has also been carried out to detect the metal loss at excavated locations observed by ICDA & ECDA. Direct assessment survey for above pipelines has been conducted and based on the survey; high consequence areas have been identified. All the high consequence area has been excavated and inspected. No appreciable corrosion and thickness loss have observed at any area. However, pipeline segments have been identified which are most vulnerable and may have corrosion in future.

Abstract Fire protection is considered only part of a facility’s safety and loss prevention program. Fire protection systems are designed to respond to events after they have occurred, and do not take into consideration other systems in place that prevent the event from occurring in the first place. In many instances, and especially after events have occurred, lawsuits have been filed, regulatory consent orders have been issued, and recommendations from outside experts and insurance companies have been issued, directly pressuring the company to take action. Other companies with similar risks have also felt indirect pressure to install additional protection systems. Good engineering judgment has not always been applied to assure that the money was well spent. This paper will present a fire protection risk assessment methodology for oil and chemical facilities. In this methodology, not only are fire protection issues considered, but also select management, process safety and engineering systems are reviewed. The systematic review of these factors will assist a facility in establishing its own risk assessment criteria. ECRC has applied and proven the benefits of this methodology at a Gulf Coast refining and petrochemical complex. This paper will summarize the results of this work.

The energy performance of buildings represents a major challenge in terms of sustainable development. The buildings and buildings construction sectors combined are responsible for over one-third of global final energy consumption and nearly 40% of total direct and indirect CO2 emissions. In order to reduce the energy consumption of buildings and their harmful impact on the environment, special attention has been paid in recent years to the use of bio-based materials. In the present paper, a model of heat and moisture transfer hollow hemp concrete wall is proposed using finite element method. The energy and mass balances are expressed using measurable transfer drivers as temperature water content and vapor pressure and coefficients related explicitly to the macroscopic properties of material as thermal conductivity, specific heat, and water vapor permeability. The proposed model is implemented in MATLAB code and validated through experimental measurements.

1.1 Macroeconomic summary Economic recovery has consistently outperformed the technical staff’s expectations following a steep decline in activity in the second quarter of 2020. At the same time, total and core inflation rates have fallen and remain at low levels, suggesting that a significant element of the reactivation of Colombia’s economy has been related to recovery in potential GDP. This would support the technical staff’s diagnosis of weak aggregate demand and ample excess capacity. The most recently available data on 2020 growth suggests a contraction in economic activity of 6.8%, lower than estimates from January’s Monetary Policy Report (-7.2%). High-frequency indicators suggest that economic performance was significantly more dynamic than expected in January, despite mobility restrictions and quarantine measures. This has also come amid declines in total and core inflation, the latter of which was below January projections if controlling for certain relative price changes. This suggests that the unexpected strength of recent growth contains elements of demand, and that excess capacity, while significant, could be lower than previously estimated. Nevertheless, uncertainty over the measurement of excess capacity continues to be unusually high and marked both by variations in the way different economic sectors and spending components have been affected by the pandemic, and by uneven price behavior. The size of excess capacity, and in particular the evolution of the pandemic in forthcoming quarters, constitute substantial risks to the macroeconomic forecast presented in this report. Despite the unexpected strength of the recovery, the technical staff continues to project ample excess capacity that is expected to remain on the forecast horizon, alongside core inflation that will likely remain below the target. Domestic demand remains below 2019 levels amid unusually significant uncertainty over the size of excess capacity in the economy. High national unemployment (14.6% for February 2021) reflects a loose labor market, while observed total and core inflation continue to be below 2%. Inflationary pressures from the exchange rate are expected to continue to be low, with relatively little pass-through on inflation. This would be compatible with a negative output gap. Excess productive capacity and the expectation of core inflation below the 3% target on the forecast horizon provide a basis for an expansive monetary policy posture. The technical staff’s assessment of certain shocks and their expected effects on the economy, as well as the presence of several sources of uncertainty and related assumptions about their potential macroeconomic impacts, remain a feature of this report. The coronavirus pandemic, in particular, continues to affect the public health environment, and the reopening of Colombia’s economy remains incomplete. The technical staff’s assessment is that the COVID-19 shock has affected both aggregate demand and supply, but that the impact on demand has been deeper and more persistent. Given this persistence, the central forecast accounts for a gradual tightening of the output gap in the absence of new waves of contagion, and as vaccination campaigns progress. The central forecast continues to include an expected increase of total and core inflation rates in the second quarter of 2021, alongside the lapse of the temporary price relief measures put in place in 2020. Additional COVID-19 outbreaks (of uncertain duration and intensity) represent a significant risk factor that could affect these projections. Additionally, the forecast continues to include an upward trend in sovereign risk premiums, reflected by higher levels of public debt that in the wake of the pandemic are likely to persist on the forecast horizon, even in the context of a fiscal adjustment. At the same time, the projection accounts for the shortterm effects on private domestic demand from a fiscal adjustment along the lines of the one currently being proposed by the national government. This would be compatible with a gradual recovery of private domestic demand in 2022. The size and characteristics of the fiscal adjustment that is ultimately implemented, as well as the corresponding market response, represent another source of forecast uncertainty. Newly available information offers evidence of the potential for significant changes to the macroeconomic scenario, though without altering the general diagnosis described above. The most recent data on inflation, growth, fiscal policy, and international financial conditions suggests a more dynamic economy than previously expected. However, a third wave of the pandemic has delayed the re-opening of Colombia’s economy and brought with it a deceleration in economic activity. Detailed descriptions of these considerations and subsequent changes to the macroeconomic forecast are presented below. The expected annual decline in GDP (-0.3%) in the first quarter of 2021 appears to have been less pronounced than projected in January (-4.8%). Partial closures in January to address a second wave of COVID-19 appear to have had a less significant negative impact on the economy than previously estimated. This is reflected in figures related to mobility, energy demand, industry and retail sales, foreign trade, commercial transactions from selected banks, and the national statistics agency’s (DANE) economic tracking indicator (ISE). Output is now expected to have declined annually in the first quarter by 0.3%. Private consumption likely continued to recover, registering levels somewhat above those from the previous year, while public consumption likely increased significantly. While a recovery in investment in both housing and in other buildings and structures is expected, overall investment levels in this case likely continued to be low, and gross fixed capital formation is expected to continue to show significant annual declines. Imports likely recovered to again outpace exports, though both are expected to register significant annual declines. Economic activity that outpaced projections, an increase in oil prices and other export products, and an expected increase in public spending this year account for the upward revision to the 2021 growth forecast (from 4.6% with a range between 2% and 6% in January, to 6.0% with a range between 3% and 7% in April). As a result, the output gap is expected to be smaller and to tighten more rapidly than projected in the previous report, though it is still expected to remain in negative territory on the forecast horizon. Wide forecast intervals reflect the fact that the future evolution of the COVID-19 pandemic remains a significant source of uncertainty on these projections. The delay in the recovery of economic activity as a result of the resurgence of COVID-19 in the first quarter appears to have been less significant than projected in the January report. The central forecast scenario expects this improved performance to continue in 2021 alongside increased consumer and business confidence. Low real interest rates and an active credit supply would also support this dynamic, and the overall conditions would be expected to spur a recovery in consumption and investment. Increased growth in public spending and public works based on the national government’s spending plan (Plan Financiero del Gobierno) are other factors to consider. Additionally, an expected recovery in global demand and higher projected prices for oil and coffee would further contribute to improved external revenues and would favor investment, in particular in the oil sector. Given the above, the technical staff’s 2021 growth forecast has been revised upward from 4.6% in January (range from 2% to 6%) to 6.0% in April (range from 3% to 7%). These projections account for the potential for the third wave of COVID-19 to have a larger and more persistent effect on the economy than the previous wave, while also supposing that there will not be any additional significant waves of the pandemic and that mobility restrictions will be relaxed as a result. Economic growth in 2022 is expected to be 3%, with a range between 1% and 5%. This figure would be lower than projected in the January report (3.6% with a range between 2% and 6%), due to a higher base of comparison given the upward revision to expected GDP in 2021. This forecast also takes into account the likely effects on private demand of a fiscal adjustment of the size currently being proposed by the national government, and which would come into effect in 2022. Excess in productive capacity is now expected to be lower than estimated in January but continues to be significant and affected by high levels of uncertainty, as reflected in the wide forecast intervals. The possibility of new waves of the virus (of uncertain intensity and duration) represents a significant downward risk to projected GDP growth, and is signaled by the lower limits of the ranges provided in this report. Inflation (1.51%) and inflation excluding food and regulated items (0.94%) declined in March compared to December, continuing below the 3% target. The decline in inflation in this period was below projections, explained in large part by unanticipated increases in the costs of certain foods (3.92%) and regulated items (1.52%). An increase in international food and shipping prices, increased foreign demand for beef, and specific upward pressures on perishable food supplies appear to explain a lower-than-expected deceleration in the consumer price index (CPI) for foods. An unexpected increase in regulated items prices came amid unanticipated increases in international fuel prices, on some utilities rates, and for regulated education prices. The decline in annual inflation excluding food and regulated items between December and March was in line with projections from January, though this included downward pressure from a significant reduction in telecommunications rates due to the imminent entry of a new operator. When controlling for the effects of this relative price change, inflation excluding food and regulated items exceeds levels forecast in the previous report. Within this indicator of core inflation, the CPI for goods (1.05%) accelerated due to a reversion of the effects of the VAT-free day in November, which was largely accounted for in February, and possibly by the transmission of a recent depreciation of the peso on domestic prices for certain items (electric and household appliances). For their part, services prices decelerated and showed the lowest rate of annual growth (0.89%) among the large consumer baskets in the CPI. Within the services basket, the annual change in rental prices continued to decline, while those services that continue to experience the most significant restrictions on returning to normal operations (tourism, cinemas, nightlife, etc.) continued to register significant price declines. As previously mentioned, telephone rates also fell significantly due to increased competition in the market. Total inflation is expected to continue to be affected by ample excesses in productive capacity for the remainder of 2021 and 2022, though less so than projected in January. As a result, convergence to the inflation target is now expected to be somewhat faster than estimated in the previous report, assuming the absence of significant additional outbreaks of COVID-19. The technical staff’s year-end inflation projections for 2021 and 2022 have increased, suggesting figures around 3% due largely to variation in food and regulated items prices. The projection for inflation excluding food and regulated items also increased, but remains below 3%. Price relief measures on indirect taxes implemented in 2020 are expected to lapse in the second quarter of 2021, generating a one-off effect on prices and temporarily affecting inflation excluding food and regulated items. However, indexation to low levels of past inflation, weak demand, and ample excess productive capacity are expected to keep core inflation below the target, near 2.3% at the end of 2021 (previously 2.1%). The reversion in 2021 of the effects of some price relief measures on utility rates from 2020 should lead to an increase in the CPI for regulated items in the second half of this year. Annual price changes are now expected to be higher than estimated in the January report due to an increased expected path for fuel prices and unanticipated increases in regulated education prices. The projection for the CPI for foods has increased compared to the previous report, taking into account certain factors that were not anticipated in January (a less favorable agricultural cycle, increased pressure from international prices, and transport costs). Given the above, year-end annual inflation for 2021 and 2022 is now expected to be 3% and 2.8%, respectively, which would be above projections from January (2.3% and 2,7%). For its part, expected inflation based on analyst surveys suggests year-end inflation in 2021 and 2022 of 2.8% and 3.1%, respectively. There remains significant uncertainty surrounding the inflation forecasts included in this report due to several factors: 1) the evolution of the pandemic; 2) the difficulty in evaluating the size and persistence of excess productive capacity; 3) the timing and manner in which price relief measures will lapse; and 4) the future behavior of food prices. Projected 2021 growth in foreign demand (4.4% to 5.2%) and the supposed average oil price (USD 53 to USD 61 per Brent benchmark barrel) were both revised upward. An increase in long-term international interest rates has been reflected in a depreciation of the peso and could result in relatively tighter external financial conditions for emerging market economies, including Colombia. Average growth among Colombia’s trade partners was greater than expected in the fourth quarter of 2020. This, together with a sizable fiscal stimulus approved in the United States and the onset of a massive global vaccination campaign, largely explains the projected increase in foreign demand growth in 2021. The resilience of the goods market in the face of global crisis and an expected normalization in international trade are additional factors. These considerations and the expected continuation of a gradual reduction of mobility restrictions abroad suggest that Colombia’s trade partners could grow on average by 5.2% in 2021 and around 3.4% in 2022. The improved prospects for global economic growth have led to an increase in current and expected oil prices. Production interruptions due to a heavy winter, reduced inventories, and increased supply restrictions instituted by producing countries have also contributed to the increase. Meanwhile, market forecasts and recent Federal Reserve pronouncements suggest that the benchmark interest rate in the U.S. will remain stable for the next two years. Nevertheless, a significant increase in public spending in the country has fostered expectations for greater growth and inflation, as well as increased uncertainty over the moment in which a normalization of monetary policy might begin. This has been reflected in an increase in long-term interest rates. In this context, emerging market economies in the region, including Colombia, have registered increases in sovereign risk premiums and long-term domestic interest rates, and a depreciation of local currencies against the dollar. Recent outbreaks of COVID-19 in several of these economies; limits on vaccine supply and the slow pace of immunization campaigns in some countries; a significant increase in public debt; and tensions between the United States and China, among other factors, all add to a high level of uncertainty surrounding interest rate spreads, external financing conditions, and the future performance of risk premiums. The impact that this environment could have on the exchange rate and on domestic financing conditions represent risks to the macroeconomic and monetary policy forecasts. Domestic financial conditions continue to favor recovery in economic activity. The transmission of reductions to the policy interest rate on credit rates has been significant. The banking portfolio continues to recover amid circumstances that have affected both the supply and demand for loans, and in which some credit risks have materialized. Preferential and ordinary commercial interest rates have fallen to a similar degree as the benchmark interest rate. As is generally the case, this transmission has come at a slower pace for consumer credit rates, and has been further delayed in the case of mortgage rates. Commercial credit levels stabilized above pre-pandemic levels in March, following an increase resulting from significant liquidity requirements for businesses in the second quarter of 2020. The consumer credit portfolio continued to recover and has now surpassed February 2020 levels, though overall growth in the portfolio remains low. At the same time, portfolio projections and default indicators have increased, and credit establishment earnings have come down. Despite this, credit disbursements continue to recover and solvency indicators remain well above regulatory minimums. 1.2 Monetary policy decision In its meetings in March and April the BDBR left the benchmark interest rate unchanged at 1.75%.