Visual Screening Procedure Research Articles

Reliability-Based Seismic Safety Assessment of the Metropolitan Cathedral of Brasília

Recent destructive earthquakes in Turkey (2023) with devastating effects have reawakened the discussion about seismic activity in Brazil and the vulnerability of the Brazilian buildings. Despite the lower magnitudes, national records should not be disregarded, as earthquakes with a magnitude below five may still cause loss of life and property damage. The assessment of existing RC buildings allows us to understand the performance of a structure during an earthquake and the adoption of mitigating measures. This paper preliminarily investigates the seismic vulnerability of the Metropolitan Cathedral in Brasilia, which was recognized as a World Heritage Site by ONU in 1987. The Rapid Visual Screening (RVS) procedure has been adopted for qualitative vulnerability assessment through the guidelines of the Japan Building Disaster Prevention Association at the procedure updated in accordance with the Brazilian reality. This research examined the structure under horizontal acceleration defined by national seismic code, and various scenarios are assumed as time aging, structural irregularities, and the level of importance of the structure. In this study, the Monte Carlo simulation is carried out to evaluate the level of safety. A performed analysis has shown that the examined building possesses the seismic capacity required against the expected earthquake motions. Even with reliability analysis, the structure achieves an acceptable level of safety. The results highlight the importance of a probabilistic approach to make reliable decisions on the conservation and rehabilitation of architectural heritage buildings.

Assessment of Seismic Vulnerability of School Buildings: A case study in Bandung, West Java, Indonesia

Indonesia is an earthquake-prone country. In many earthquakes, school buildings suffer the most damage than other public facilities. In 2020, the conditions of around 70% of 218,234 school classrooms in Indonesia were deteriorating. This contributed to a significant earthquake vulnerability. Limited funding for rehabilitation and renovation became an obstacle to reduce the vulnerability. This study proposed that Rapid Visual Screening (RVS), which is a simple method and has a wide coverage, could be a solution to prioritize building rehabilitation. Bandung, the capital city of the most populated province in Indonesia, has complex earthquake hazard risks, which made it a suitable study area for implementing RVS. This study conducted a seismic vulnerability assessment of school buildings in the city of Bandung, Indonesia. The methodology used is based on Indonesia National Disaster Management Agency (BNPB)’s Regulation No. 4 of 2012 on Rapid Visual Screening (RVS) procedure compared to FEMA 154 RVS procedure with local hazard data and building data. RVS was conducted in total 334 elementary school buildings in 30 districts. The result of the BNPB’s RVS procedure showed an average RVS score (S) of 4.455 where 36.53% buildings were in safe condition and 63.47% buildings required further assessment of the conditions from construction experts. The result of the FEMA 154 RVS procedure showed an average RVS score (S) of 0.905 where 22.16% of the buildings were in high probability of grade 4 damage and 77.84% of the buildings were in high probability of grade 3 damage.

Development and rapid visual screening analysis of an Italian masonry building portfolio using post-earthquake damage observations

The damage observed during the seismic events occurred in Italy over the years have highlighted the seismic vulnerability of the existing masonry buildings. A significant percentage of the Italian masonry building heritage was built before the introduction of seismic provisions and their design was essentially based on the experience of professionals. Depending on the main characteristics of these buildings, both local and global damage mechanisms were observed during the post-earthquake inspections following the seismic events that occurred in Italy in the last 50 years, which have been cataloged by the Italian Civil Protection Department in the Da.D.O. platform (Observed Damage Database - Observed Damage Database). Using the data available in the Da.D.O. platform, this paper processes the main characteristics of the masonry buildings damaged by the 2009 L'Aquila earthquake to develop a representative masonry building portfolio. Such masonry buildings were then evaluated through nonlinear static analyses to identify the main sources of structural weakness and to develop or calibrate a simplified rapid visual screening (RVS) procedure. For this purpose, various RVS methods were applied to a number of buildings of the portfolio, obtaining different vulnerability indices to be scrutinized and compared with those obtained through FEM analytical methods. This ultimate goal is to identify the most seismically vulnerable buildings, with a view to prioritization, and to assist decision makers in implementing seismic risk reduction strategies.

Large-scale seismic assessment of RC buildings through rapid visual screening

Rapid urban growth, particularly in developing countries, is often accompanied by unplanned and highly vulnerable settlements which could lead to high seismic risk. This problem becomes even more pronounced when such developing countries are located in seismic prone regions, which, without a well-enforced seismic code, face high probability of major human and economic losses following a seismic event. With this in mind, large-scale rapid visual screening (RVS) procedures to perform seismic vulnerability assessment are of paramount importance to, at least, obtain a preliminary estimate of the risk to which buildings of a certain region are exposed to. RVS methods generally provide a seismic risk index based on the site hazard, the structural vulnerability and the exposure. This paper presents one of many available RVS procedures, applied and assessed for large-scale seismic vulnerability mapping of a case-study province in Northern Algeria. Based on data collected during ad-hoc field surveys, the index-based selected RVS methodology was adapted to the reinforced concrete (RC) portion of the building portfolio, featuring over 2900 buildings, to estimate its seismic vulnerability. Taking advantage of a large amount of available data, a parametric study was then performed to understand the effect of the individual variables used in the RVS method on the vulnerability indices of the different buildings. The consistency of the method, as evidenced by the results found across different building stock typologies, was also investigated to confirm the soundness of RVS approaches in large-scale assessments. Furthermore, in specific for the case-study region, the outcome of this study is extremely useful for preliminary identification of buildings (or building classes) more prone to earthquake damage and to assist decision-makers in planning seismic risk reduction strategies.

Seismic Vulnerability Assessment of Buildings for Seismic Retrofitting Strategies: Rapid Visual Screening Method

The objective of this study is to provide the assessment of the seismic vulnerability of R.C.C. and Load bearing structures by the Rapid Visual Screening Method. As Rapid Visual Screening is a preliminary stage to conducting a Simplified Vulnerability Assessment of the building.The rapid visual screening procedure requires only a visual evaluation and a few additional details. These procedures are recommended for all buildings. Rapid Visual Screening score has been evaluated for the various building which suggests further assessment for Seismic Vulnerability. India is expected to be the most populous country in the world by 2025. India has a huge volume of building stocks at present, and most of them are significantly vulnerable to earthquake hazards. In order to overcome this issue, firstly it is required to conduct the seismic vulnerability assessment at a massive scale of building stocks and buildings with a high probability of damage further evaluated with the simplified vulnerability assessment method procedures. After a detailed evaluation, it recommends a suitable retrofitting strategy. In this paper, we have studied various parameters of the Rapid Visual Screening method and the procedure to conduct it. Keywords: Seismic vulnerability, Existing Building, Simplified Vulnerability Assessment, Method, Rapid Visual Screening, Detailed vulnerability assessment.

Visual Screening Programs in British Columbia Schools

The purpose of this investigation was to deter­mine whether changes had occurred in visual screening procedures used in British Columbia schools during the last five years. The findings were obtained from a 95% return of questionnaires sent to the 75 school districts in British Columbia. A majority of districts continued to rely primarily on the use of far-point acuity testing by means of an eye-chart. Greater use of learning assistance teachers and of community vision specialists - optometrists and ophthalmologists - appears now to be made when children have reading difficulties.

Analysis of the occurrence of microplastics in beach sand on the Brazilian coast

The occurrence of microplastics in coastal areas is a growing concern due to the increase in plastic waste pollution in recent decades. This study had as objective to evaluate the occurrence of microplastics in Brazilian beach sand, using a simple and fast methodology. In addition, possible microplastics were classified according to color, shape and chemical composition. The study was conducted on six beaches on the Brazilian coast: Pecado Beach (RJ), Castanheiras Beach (ES), Regência Beach (ES), Imbassaí Beach (BA), Viral Beach (SE) and Ponta dos Mangues Beach (SE). The methodology was adapted from international protocols, with section demarcation (100 m), where samples were collected from the superficial layer of the beach sand in ten quadrants (50 cm × 50 cm). The laboratory extraction procedure consisted of the density separation technique in two stages: the first used sodium chloride solution and the second used zinc chloride solution. For the visual inspection and screening procedures, a stereoscopic microscope was used. A total of 166 items of microplastics were collected on the six beaches on the Brazilian coast under study. The largest quantity of possible microplastics was recorded on the beaches of Viral (SE) and Ponta dos Mangues (SE) with 30.4 items/m2 and 17.4 items/m2, respectively. Regarding colour, white items were predominant (49.3%), and among particle types, fragments represented 85.1%. In addition, some microplastic particles were sent for FT-IR analysis, one of which was identified as being polyethylene. This study contributes to the knowledge of the presence of microplastics in different locations, and to supporting decision makers regarding coastal management.

Seismic vulnerability assessment of building stock of Malakand (Pakistan) using FEMA P-154 method

Earthquakes have caused huge infrastructural damages along with loss of lives in the recent past. Continuous subduction of the Indian plate beneath the Eurasian plate has made Pakistan a seismically active region in the world. Malakand, located in the Khyber Pakhtunkhwa Province of Pakistan, is declared at high earthquake risk by the National Disaster Management Authority of Pakistan, warranting a seismic vulnerability assessment study for its existing building stock. Vulnerability assessment of a representative sample of different building use-types was carried out using the rapid visual screening (RVS) procedure of FEMA P-154. The sample size was calculated based on Yamane formula. RVS sheets are used to calculate structural scores, and likely seismogenic damage is depicted as a function of damage grades of European Macro Seismic Scale. Of the building stock inspected, it was observed that almost half of the buildings fall in damage grade 4 and 5, implying a strong probability of heavy structural and non-structural damages in the case of future earthquake occurrence. Government school buildings were found to be less vulnerable than private counterparts. Most of the commercial buildings were not constructed according to building code, making them highly susceptible to damage. Based on the results of vulnerability assessment of building structures, the article recommends implementation of building codes which can lead to a decrease in infrastructural damages and economic losses in the wake of a future seismic event.

The Effect of Instructor-Produced Videos as Supplemental Material for Training Visual Screening Procedures in Occupational Therapy Education

The Effect of Instructor-Produced Videos as Supplemental Material for Training Visual Screening Procedures in Occupational Therapy Education

A Proposed Rapid Visual Screening Procedure for Developing Countries

Many earthquakes in the past had shown that major damage to structures took place in the absence of proper design, construction, and quality control. Based on the extent of damages caused by earlier earthquakes and the building vulnerability parameters that has caused the damages, a statistical analysis was carried out to develop a vulnerability score sheet. In this score sheet, a vulnerability score is computed considering building attributes such as soft storey, substantial overhang, re-entrant corners, the age of buildings, apparent material and construction quality, eccentric staircase location with respect to building plan, maintenance, soil type and a number of storeys. This score sheet will be a very helpful technique for assessing huge building stocks.

İstanbul’un Esenler İlçesinde yer alan Betonarme Yapıların Sismik Hasar Görebilirliğinin Değerlendirilmesi

Istanbul is one of the largest cities of Turkey which is located on the regions where there is high seismic activities. Recent studies performed on mid-rise reinforced concrete (RC) structures showed that majority of the existing building stock does not conform to current seismic code requirements and they can be evaluated as vulnerable structures. The seismic performance evaluation of an existing buildings can be conducted by using nonlinear procedures stated in Turkish Earthquake Code (TEC-07). According to the code, an existing building completing its economic lifetime and/or having a performance level in between “Life Safety” to “Collapse Prevention” under the effect of Design Earthquake is defined as “building under seismic risk”. Before going into such a detailed seismic evaluation procedure for each building, there is a need for regional screening surveys to rank the building stock in terms of the potential seismic hazard. This study aims to assess the seismic vulnerability of a group of midrise RC buildings located in Esenler District of Istanbul employing the Rapid Visual Screening (RVS) procedure. In this study, valuable results have been derived to rank the buildings in terms of seismic vulnerability of existing structures located in Istanbul. It is concluded that the number of stories is the key parameter to change the priority range of the building from lowest to highest level. Majority of the buildings with the highest priority level (0≤PS≤30) suffer from the parameters related with poor construction quality, soft story irregularity and the heavy overhang. The aforementioned method could be used to estimate the performance scores of the buildings to determine the priority for more detailed seismic risk assessment procedures.

Rapid visual screening procedure of existing building based on statistical analysis

A statistical regression method was used to model the relationship between the outcome variable, e.g. different damage grade of existing building during an earthquake, and the explanatory variables concerning the building attributes that enhance the vulnerability of building during an earthquake. The analysis was performed by employing a building database of 396 damaged buildings surveyed after the 4th January Manipur earthquake of 2016. It is observed that the type of soil, apparent construction quality, maintenance condition, age of the buildings, substantial overhang and number of storey of the existing buildings are highly significant parameters in analyzing the vulnerability of the building during an earthquake. From the statistical analysis, a rapid visual screening procedure is proposed which can used as preliminary assessment technique for identifying vulnerable buildings in disaster risk reduction programme.

Rapid visual screening of earthquake-susceptible buildings

Many people in the Indian subcontinent can only afford non-engineered shelters. Unfortunately, such buildings are easy victims of earthquakes and they need to be assessed and graded to see how susceptible they are to damage during the frequent, moderate tremors of the region. The large number of these buildings warrants a wide screening programme but a dearth of technical personnel requires a simple methodology that can be carried out by non-technical people. This paper discusses the strategies for evolving a rapid visual screening procedure for non-engineered and semi-engineered buildings as a means of seismic vulnerability assessment. It is based on damage surveys of three moderate earthquakes and from shake-table experiments. The proposed methodology can be applied to traditional and semi-engineered buildings using a number of visually identifiable parameters.

Development of Visual Field Screening Procedures: A Case Study of the Octopus Perimeter.

PurposeWe develop a methodology for designing perimetric screening procedures, using Octopus perimeters as a case study.MethodsThe process has three stages: analytically determining specificity and number of presentations required for different multisampling suprathreshold schemes at a single location of the visual field, ranking visual field locations by their positive predictive value (PPV) for glaucoma, and determining a pass/fail criteria for the test. For the case study the Octopus G-program visual field test pattern is used, and a dataset of 385 glaucoma and 86 normal patients.ResultsUsing a 1-of-3 sampling strategy at a level equal to the 95 percentile of normal observers gave the most robust specificity under the influences of false-negative responses using an average of 1.5 presentations per location. The PPV analysis gave 19 locations that completely classified our glaucomatous data. A further 9 points were added to screen for nonglaucomatous loss. The final stage found that insisting that 3 locations are missed for the screening to fail gave a simulated specificity and sensitivity of approximately 95% for unreliable responders.ConclusionsOur method gives a principled approach to choosing between the many parameters of a visual field screening procedure. We have developed a procedure for the Octopus that should terminate in less than 1 minute for normal observers with high specificity and sensitivity to glaucoma.Translational RelevanceVisual field screening is used in community settings and eye care practice. This study provides a principled approach to the development of such screening procedures and details a new procedure.

Rapid seismic vulnerability assessment of building stocks for developing countries

While dealing with a large building stocks, one needs rapid visual screening procedures to identify buildings susceptible to earthquake damage. Relevant structural characteristic information is collected and used to determine a structural score, which should indicate if a building requires further investigation. This paper presents a procedure for rapid visual screenings for building stocks constructed in developing countries. Score sheets are prepared for three seismicity viz. low, moderate and high. Structural scores are related with damage grades I to V. The structural score <0.7 indicates high vulnerability requiring detail evaluation and retrofitting of the building.

Review on Rapid Seismic Vulnerability Assessment for Bulk of Buildings

This paper provides a brief overview of rapid visual screening (RVS) procedures available in different countries with a comparison among all the methods. Seismic evaluation guidelines from, USA, Canada, Japan, New Zealand, India, Europe, Italy, UNDP, with other methods are reviewed from the perspective of their applicability to developing countries. The review shows clearly that some of the RVS procedures are unsuited for potential use in developing countries. It is expected that this comparative assessment of various evaluation schemes will help to identify the most essential components of such a procedure for use in India and other developing countries, which is not only robust, reliable but also easy to use with available resources. It appears that Federal Emergency Management Agency (FEMA) 154 and New Zealand Draft Code approaches can be suitably combined to develop a transparent, reasonably rigorous and generalized procedure for seismic evaluation of buildings in developing countries.

An inventory of buildings in the city of Tunis and an assessment of their vulnerability

Tunis is a densely populated city. Its building stock was constructed without any seismic design code and mostly over soft soils. These facts make a seismic risk assessment of the city necessary. To prepare a large-scale vulnerability assessment of the buildings of Tunis, the following methodology was employed: (1) a collection of data based on a rapid visual screening procedure was gathered using an inventory form. These data were composed of files and information placed at the disposal of the authors by the municipality of Tunis. The data also contained information gathered by surveys carried out by engineering departments and information gathered from building owners. (2) A classification of building typologies was carried out considering construction material, structural system, age, height, function and state of maintenance. A measure of seismic vulnerability was assigned to each typology considering the first two parameters. (3) A large-scale vulnerability assessment using two methods was conducted for buildings for which few data were available. Vulnerability methods inspired by the EMS98 concepts and the Italian GNDT concepts were modified and applied to pilot-scale buildings located in the downtown zone (Habib Bourguiba Avenue) and in the old zone (Medina). The data analysis, through the application of the two methods, suggests that the vulnerability of buildings surveyed in Tunis is significant and risk mitigation efforts are necessary.

Strongest Cyclone of the New Millennium in the Bay of Bengal: Strategy of RVS for Nonengineered Structures

Coastal areas of the Indian subcontinent are familiar with aftermaths of severe tropical cyclones. Nonengineered structures of the common people are major casualties of these natural disasters. The present paper documents features of damages due to the 2007 Cyclone Sidr, the strongest cyclone in the Bay of Bengal portion of the Indian Ocean in the new millennium. A critical analysis of the documented damages is followed by suggestions regarding the adoption of relevant remedial measures during future constructions in the coastal regions compatible with the socioeconomic situation. In the absence of any rapid visual screening (RVS) procedure for cyclones, the paper further discusses strategies for evolving RVS procedures for cyclone-affected nonengineered structures as part of a quick and easy vulnerability assessment. The application of the proposed RVS methodology, consisting of 11 visually identifiable parameters and basic scores for eight different types of nonengineered or semiengineered buildings, is cross-checked for two cases whose RVS scores strongly match those of the proposal.

Phenomic technologies in drug discovery of neglected diseases

Leishmaniasis, Chagas Disease and Dengue are examples of neglected infectious disease that, together with Malaria, are responsible for over 1 million deaths each year. In all cases, new treatments are badly needed. Malaria treatment, although available, is becoming problematic due to worldwide spread of parasite resistance to drugs. For Leishmaniasis, drugs are often ineffective due to the pathogens’ resistance, and in some cases the drugs themselves are potentially deadly for patients. For Chagas, available treatment is often ineffective past the acute phase of the disease, and for Dengue there is no current treatment available at all. IP-Korea develops Phenomic Screen™, image-based high-content/high-throughput screening assays to find new drugs against Leishmaniasis. Using a whole-cell-based approach, we designed assays that allow selection of compounds that have potent activity against pathogens and are not toxic for the human cells. These cellular assays were adapted to high-throughput for automated image acquisition. Using this technology we have screened 200,000 drugs that impair the growth of the most deadly species causing visceral Leishmaniasis, inside their natural host cell, the human macrophages. We have also developed a phenotypic screen for Chagas disease and screened 150,000 compounds, in collaboration with Pfizer and the Drugs for Neglected Diseases initiative (DNDi), for their ability to inhibit Trypanosoma cruzi, the parasite causing Chagas, inside human host cells. Also, we established visual screening procedure to screen human genome in high content imaging mode within 8h. Genome-wide RNAi screening to identify human host proteins that are required in Chagas disease infection has been finished. The identification of these factors provides potential new targets for anti-parasitic therapies. Dengue is still in the early stage but is progressing towards the development of a cell-based high-throughput screening assay using different virus serotypes and clinical isolates. For malaria, we are developing HCS/HTS assays that target the invasion of human red blood cells by the deadliest of all malaria parasites, P. falciparum. We have screened 80,000 compounds for their antimalarial activity, and the selected hits will be re-tested for their ability to interfere with the invasion pathway using an image based high-content assay. In parallel, we are developing a phenotypic assay to screen for drugs that interfere with P. falciparum infected red blood cells cytoadhesion, one the main pathogenic mechanism of this parasite.

A Proposed Rapid Visual Screening Procedure for Seismic Evaluation of RC-Frame Buildings in India

Poor performance of reinforced concrete (RC) frame buildings in India during past earthquakes has been a matter of serious concern. Hence, it becomes important to identify and strengthen the deficient buildings. When dealing with a large building stock, one needs evaluation methods for quick assessment of the seismic safety of existing buildings so that corrective retrofitting measures may be undertaken on the deficient buildings. This paper presents a review of some of the available methods for rapid visual screening (RVS) of RC-frame buildings and proposes a RVS method for RC-frame buildings in India based on systematic studies on damage data of the 2001 Bhuj earthquake.