An Assessment to Benchmark the Seismic Performance of a Code-Conforming Reinforced-Concrete Moment-Frame Building

This report describes a state-of-the-art performance-based earthquake engineering methodology that is used to assess the seismic performance of a four-story reinforced concrete (RC) office building that is generally representative of low-rise office buildings constructed in highly seismic regions of California. This “benchmark” building is considered to be located at a site in the Los Angeles basin, and it was designed with a ductile RC special moment-resisting frame as its seismic lateral system that was designed according to modern building codes and standards. The building’s performance is quantified in terms of structural behavior up to collapse, structural and nonstructural damage and associated repair costs, and the risk of fatalities and their associated economic costs. To account for different building configurations that may be designed in practice to meet requirements of building size and use, eight structural design alternatives are used in the performance assessments. Our performance assessments account for important sources of uncertainty in the ground motion hazard, the structural response, structural and nonstructural damage, repair costs, and life-safety risk. The ground motion hazard characterization employs a site-specific probabilistic seismic hazard analysis and the evaluation of controlling seismic sources (through disaggregation) at seven ground motion levels (encompassing return periods ranging from 7 to 2475 years). Innovative procedures for ground motion selection and scaling are used to develop acceleration time history suites corresponding to each of the seven ground motion levels. Structural modeling utilizes both “fiber” models and “plastic hinge” models. Structural modeling uncertainties are investigated through comparison of these two modeling approaches, and through variations in structural component modeling parameters (stiffness, deformation capacity, degradation, etc.). Structural and nonstructural damage (fragility) models are based on a combination of test data, observations from post-earthquake reconnaissance, and expert opinion. Structural damage and repair costs are modeled for the RC beams, columns, and slabcolumn connections. Damage and associated repair costs are considered for some nonstructural building components, including wallboard partitions, interior paint, exterior glazing, ceilings, sprinkler systems, and elevators. The risk of casualties and the associated economic costs are evaluated based on the risk of structural collapse, combined with recent models on earthquake fatalities in collapsed buildings and accepted economic modeling guidelines for the value of human life in loss and cost-benefit studies. The principal results of this work pertain to the building collapse risk, damage and repair cost, and life-safety risk. These are discussed successively as follows. When accounting for uncertainties in structural modeling and record-to-record variability (i.e., conditional on a specified ground shaking intensity), the structural collapse probabilities of the various designs range from 2% to 7% for earthquake ground motions that have a 2% probability of exceedance in 50 years (2475 years return period). When integrated with the ground motion hazard for the southern California site, the collapse probabilities result in mean annual frequencies of collapse in the range of [0.4 to 1.4]x10 -4 for the various benchmark building designs. In the development of these results, we made the following observations that are expected to be broadly applicable: (1) The ground motions selected for performance simulations must consider spectral shape (e.g., through use of the epsilon parameter) and should appropriately account for correlations between motions in both horizontal directions; (2) Lower-bound component models, which are commonly used in performance-based assessment procedures such as FEMA 356, can significantly bias collapse analysis results; it is more appropriate to use median component behavior, including all aspects of the component model (strength, stiffness, deformation capacity, cyclic deterioration, etc.); (3) Structural modeling uncertainties related to component deformation capacity and post-peak degrading stiffness can impact the variability of calculated collapse probabilities and mean annual rates to a similar degree as record-to-record variability of ground motions. Therefore, including the effects of such structural modeling uncertainties significantly increases the mean annual collapse rates. We found this increase to be roughly four to eight times relative to rates evaluated for the median structural model; (4) Nonlinear response analyses revealed at least six distinct collapse mechanisms, the most common of which was a story mechanism in the third story (differing from the multi-story mechanism predicted by nonlinear static pushover analysis); (5) Soil-foundation-structure interaction effects did not significantly affect the structural response, which was expected given the relatively flexible superstructure and stiff soils. The potential for financial loss is considerable. Overall, the calculated expected annual losses (EAL) are in the range of $52,000 to$97,000 for the various code-conforming benchmark building designs, or roughly 1% of the replacement cost of the building ($8.8M). These losses are dominated by the expected repair costs of the wallboard partitions (including interior paint) and by the structural members. Loss estimates are sensitive to details of the structural models, especially the initial stiffness of the structural elements. Losses are also found to be sensitive to structural modeling choices, such as ignoring the tensile strength of the concrete (40 EAL) or the contribution of the gravity frames to overall building stiffness and strength (15 change in EAL). Although there are a number of factors identified in the literature as likely to affect the risk of human injury during seismic events, the casualty modeling in this study focuses on those factors (building collapse, building occupancy, and spatial location of building occupants) that directly inform the building design process. The expected annual number of fatalities is calculated for the benchmark building, assuming that an earthquake can occur at any time of any day with equal probability and using fatality probabilities conditioned on structural collapse and based on empirical data. The expected annual number of fatalities for the code-conforming buildings ranges between 0.05*10 -2 and 0.21*10 -2 , and is equal to 2.30*10 -2 for a non-code conforming design. The expected loss of life during a seismic event is perhaps the decision variable that owners and policy makers will be most interested in mitigating. The fatality estimation carried out for the benchmark building provides a methodology for comparing this important value for various building designs, and enables informed decision making during the design process. The expected annual loss associated with fatalities caused by building earthquake damage is estimated by converting the expected annual number of fatalities into economic terms. Assuming the value of a human life is$3.5M, the fatality rate translates to an EAL due to fatalities of $3,500 to$5,600 for the code-conforming designs, and $79,800 for the non-code conforming design. Compared to the EAL due to repair costs of the code-conforming designs, which are on the order of$66,000, the monetary value associated with life loss is small, suggesting that the governing factor in this respect will be the maximum permissible life-safety risk deemed by the public (or its representative government) to be appropriate for buildings. Although the focus of this report is on one specific building, it can be used as a reference for other types of structures. This report is organized in such a way that the individual core chapters (4, 5, and 6) can be read independently. Chapter 1 provides background on the performance-based earthquake engineering (PBEE) approach. Chapter 2 presents the implementation of the PBEE methodology of the PEER framework, as applied to the benchmark building. Chapter 3 sets the stage for the choices of location and basic structural design. The subsequent core chapters focus on the hazard analysis (Chapter 4), the structural analysis (Chapter 5), and the damage and loss analyses (Chapter 6). Although the report is self-contained, readers interested in additional details can find them in the appendices

Coherent Coupling of Multiple Transverse Modes in Quantum Cascade Lasers

Quantum cascade lasers are a unique laboratory for studying nonlinear laser dynamics because of their high intracavity intensity, strong intersubband optical nonlinearity, and an unusual combination of relaxation time scales. Here we investigate the nonlinear coupling between the transverse modes of quantum cascade lasers. We present evidence for stable phase coherence of multiple transverse modes over a large range of injection currents. We explain the phase coherence by a four-wave mixing interaction originating from the strong optical nonlinearity of the gain transition. The phase-locking conditions predicted by theory are supported by spectral data and both near- and far-field mode measurements.Engineering and Applied Science

Cloud e-learning for mechatronics: CLEM

his paper describes results of the CLEM project, Cloud E-learning for Mechatronics. CLEM is an example of a domain-specific cloud that is especially tuned to the needs of VET (Vocational, Education and Training) teachers. An interesting development has been the creation of remote laboratories in the cloud. Learners can access such laboratories to support their practical learning of mechatronics without the need to set up laboratories at their own institutions. The cloud infrastructure enables multiple laboratories to come together virtually to create an ecosystem for educators and learners. From such a system, educators can pick and mix materials to create suitable courses for their students and the learners can experience different types of devices and laboratories through the cloud. The paper provides an overview of this new cloud-based e-learning approach and presents the results. The paper explains how the use of cloud computing has enabled the development of a new method, showing how a holistic e-learning experience can be obtained through use of static, dynamic and interactive material together with facilities for collaboration and innovation

A Rare Tumor Case in an Adult Patient with Neurofibromatosis: Lumbar Ependymoma

In patients with type 1 neurofibromatosis (NF1), there is an increased susceptibility to tumor development in the central nervous system due to the loss of neurofibromin, an inactivator of the protooncogene Ras. NF1 has a broad clinical spectrum,which includes spinal tumors. Although the most common intramedullary tumor of the spinal cord in adults is ependymoma, few patients with NF1 accompanied by spinal ependymoma have been reported to date, and the localization of the tumors is cervical and thoracic in these cases. In this study, we report the case of a patient with NF1 presenting to our clinic with low back pain and gait disturbance. The patient had an intradural extramedullary ependymoma at the L2-3 vertebra level. This report is the first case of NF1 with spinal ependymoma localized in the lumbar region

The Effect of Covid-19 Outbreak on Turkish Diesel Consumption Volatility Dynamics

We analyze the effect of the COVID-19 outbreak on volatility dynamics of the Turkish diesel market. We observe that a high volatility pattern starts around mid-April, 2020 and reaches its peak on 24/05/2020. This is due to the government imposed weekend curfews and bans on intercity travels. Two policy suggestions are provided. First is a temporary rearrangement of profit margins of dealers and liquid fuel distributors; and, second is a temporary tax regulation to compensate lost tax revenue

How sustainable is Türkiye's food import? A linearized almost ideal demand system estimation for food import elasticities

This study examines the import demand for four key agricultural commodities—cereals, meat, sugar, and vegetable oils—in Türkiye, using a Linear Almost Ideal Demand System (AIDS) model. Spanning the period from 1986 to 2020, the analysis focuses on these commodities as they constitute over 90% of Türkiye's food import budget. The results reveal significant long-run own-price elasticities, with vegetable oils and cereals being particularly sensitive to price changes, whereas the impact of price on meat and sugar imports is negligible. The study also highlights the limited role of income and exchange rates on import demand, except for sugar where the exchange rate has a significant but small positive effect. Short-run estimates indicate a heightened responsiveness of budget allocations for cereals and vegetable oils to price fluctuations, suggesting a persistent element in food import patterns over time. The findings underscore the essential nature of these commodities, with low own-price elasticity for cereals and vegetable oils, reflecting their status as necessities. In contrast, short-run elasticity results suggest that cereal imports may be viewed as a luxury, with the potential for domestic production to substitute imports. The study concludes that Türkiye's food security is increasingly vulnerable to global price fluctuations, particularly for vegetable oils, and calls for policies that stabilize exchange rates and inflation while enhancing domestic agricultural productivity to mitigate this risk

Effect of animal breed, season and milk production scale on somatic cell count and composition of cow milk

Production of high quality dairy products requires profound knowledge about factors conducting raw milk quality. Therefore, the present study aimed to provide to dairy processors the necessary information for the effect of animal breed, season and milk production scale on the quality and technological properties of raw milk. In this respect, the main composition parameters (total solids, milk fat, protein content) and microbiological parameters (somatic cell count (SCC) and total viable count (TVC)) of bulk raw milk collected from small-scale producers and of raw milk from Simmental, Holstein and Jersey breeds produced in large-scale farms were studied over a one year period. Total solids, protein and fat levels in bulk milk demonstrated seasonal trends. Milk fat and protein contents were the highest in autumn and winter and the lowest in spring and summer. However, no significant seasonal variations were detected in total solids, milk fat and protein contents in the milk from large-scale farms. The values of these parameters were significantly higher (P<0.05) in milk from Jersey breed in comparison with the other two breeds studied. Lower TVC and SCC of milk produced by large-scale farms in comparison with small-scale producers were found. The SCC values of bulk milk samples were significantly higher (P < 0.05) during the autumn-winter period compared to spring and summer. The milk produced by large-scale producers lacks significant seasonal variations of SCC. It was found that the SCC of milk from Jersey breed is statistically (P < 0.05) higher than that the other breeds studied. © 2017, National Centre for Agrarian Sciences. All rights reserved

The relation of the pleural thickening in tuberculosis pleurisy with the activity of adenosine deaminase

Selvi, A. Kant, S. Arslan, M. Ozgel. Background: Residual pleural thickening (RPT) still occurs in most patients with tuberculosis pleurisy despite advances in the treatment of tuberculosis. The aim of this study was to evaluate the significance of RPT in tuberculosis pleurisy with the patients clinical findings, biochemical and microbiological properties of pleural effusion and with the total adenosine deaminase (ADA) and isoenzymes levels. Methods: 121 tuberculosis pleurisy patients were evaluated retrospectively. According to posteroanterior chest x-rays, the 63 (52%) cases with the thickness 2 mm or more in lower lateral hemithorax were grouped as I and the 58 (48%) cases without pleural thickness were grouped as II. The amount of pleural effusion was classified into small, medium or massive according to their chest x-rays. In both groups; sex, age, symptoms score, bacteriological and biochemical tests and ADA levels were recorded. Results: 81 (67%) male and 40 (33%) female, overall 121 patients were enrolled into the study. RPT was found higher in males (p=0.014) and the increase ran parallel with the amount of cigarette smoking (p=0.014). RPT was found to be lower in small effusions (p=0.001). The group with RPT, the serum albumin was found lower (p=0.002), pleural fluid total protein (p=0.047) and the ratio of pleural fluid protein to serum protein (p=0.002) were found higher. In group I, total ADA: 69.5±38.9 IU/L and ADA2: 41.3±31.6 IU/L were higher than the cases without RPT (p=0.032, p=0.017, respectively). Conclusions: We suggest that the immunological mechanisms are effective in the development of pleural thickening

Multiarticular chronic tophaceous gout with severe and multiple ulcerations: a case report

<p>Abstract</p> <p>Introduction</p> <p>Gout is a common inflammatory arthritis caused by articular precipitation of monosodium urate crystals. It usually affects the first metatarsophalangeal joint of the foot and less commonly other joints, such as wrists, elbows, knees and ankles.</p> <p>Case presentation</p> <p>We report the case of a 75-year-old Caucasian man with tophaceous multiarticular gout, soft-tissue involvement and ulcerated tophi on the first metatarsophalangeal joint of the left foot, on the first interphalangeal joint of the right foot and on the left thumb.</p> <p>Conclusion</p> <p>Ulcers due to tophaceous gout are currently uncommon considering the positive effect of pharmaceutical treatment in controlling hyperuricemia. Surgical treatment is seldom required for gout and is usually reserved for cases of recurrent attacks with deformities, severe pain, infection and joint destruction.</p