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By Nehad Elsafty

It is always necessary to expand existing buildings, so that they could meet the growing societal needs. Compared with demolishing them and then constructing new ones, the expansion of existing buildings could not only reduce project cost, but also save the use of energy and raw materials in projects. Therefore, it is widely adopted in most under-developed countries. However, the expansion of existing buildings is not an easy task. It has been involved with a lot of issues in defining the scope of work, planning landscape, managing construction activities, etc. This paper investigates the potential challenges in expanding existing buildings. The project of expanding the Al-Agoza Hospital, one of the biggest and oldest hospitals in Cairo, Egypt, is selected as a case study. In the case study, the project documents have been carefully reviewed. The project engineers and the health-care professionals working in the hospital have been interviewed. This way, the point of views from the owner, the architect/engineer, and the contractor have been taken into account. Several lessons are learned through the discussion with these people. The results from this paper are expected to provide pieces of useful advice and suggestion for the expansion of existing buildings in the future.

Aug 1, 2013

By Magdy Ibrahim

This paper presents experimental design and development of a low-cost remote sensing hardware designed to support automated site data acquisition for near real-time progress reporting of construction operations. The developed hardware utilizes open source microcontroller equipped with multiple sensors that include 3D accelerometer, GPS, Data logger and Bluetooth. The use of open source microcontroller makes the developed design cost effective; freeing it from the need for costly license fees. Its platform configuration is flexible; enabling the addition of temperature, weight and other sensors, Wi-Fi and Xbee capabilities to suit individual field applications. Pilot tests have been carried out in laboratory and outdoor environments. The results prove effectiveness and robustness of the developed configuration. The paper provides description of the individual components used in the development of this prototype hardware. It also describes the technical characteristics, capabilities and limitations of the developed hardware. The findings of comparison with alternative technologies used for outdoor tracking of construction operations are presented. The comparison is carried out with respect to range, cost and suitability for outdoor environment. The developed hardware is expected to support a wide range of applications including tracking of earthmoving operations, highway construction and onsite resources. As well, it is expected to enhance safety on construction jobsites.

Aug 1, 2013

By Yu Chen, Charlie C. Li

The application of rock bolts for the stabilisation of underground openings needs a good understanding of the response of the bolts during rock excavation. The pull-and-shear performance of two types of rock bolts—that is, the fully encapsulated rebar and the D-Bolt—has been studied both experimentally and numerically. The rock bolts were tested under a pull-and-shear load at five displacing angles (i.e., 0°, 20°, 40°, 60°, and 90°), and at the same time, the strains on the bolts were monitored during testing. The two types of rock bolts have similar loading capacities, while the loading angle has obvious influence on the deformation capacity of the D-Bolt. The ultimate total displacement of the D-Bolt decreases from 140 mm under pure pull loading to 70 mm under shearing. The displacement capacity of the rebar is not significantly influenced by the loading angle but remains at a quite low level from 29 to 53 mm. The D-Bolt yielded in a longer section the rebar bolt under pure shear. A trilinear material model was used to simulate the strain hardening behaviour of the bolt steels in the numerical code FLAC3D. The numerical results show that the axial load in the bolt decreases exponentially with the distance from the loading position for the rebar bolts, but it remains constant in the bolt sections between the anchor positions for the D-Bolts. When the bolt is subjected to a lateral load, shear stresses are created on the D-Bolt surface within a short distance from the loading position.

Jan 1, 2015

By H. Q. Fan

Construction equipment is an important type of resources of heavy construction contractors. Since equipment breakdowns can cause project delays and significant financial losses, the contractors are eager to know those factors causing equipment failures directly or indirectly, related to equipment design, maintenance, and operations. Although Bayesian network can be used for diagnostic analysis of failure events or making predictive analysis, building a Bayesian network for such purpose can be difficult as the cause-effect relations can be subjective and their conditional probabilities change with a wide variety of causal factors. A hybrid approach is proposed in this paper to update the Bayesian diagnostic network structures and parameters using real life data, the conditional probabilities and cause-effect relationships can be dynamically updated with observed failure records to reflect the real life situations of a complex equipment system. A case study is conducted to show the benefits of the hybrid approach in construction equipment diagnostic analysis.

Aug 1, 2013

By A. Hayatdavoudi, K. G. Sawant, F. Boukadi

"In this work, we found that contact between shale and water results in development of micro fractures. Based on results of experiments on Pierre shale, we conclude that appearance of micro fractures begin with saturation of capillaries, ionic and diffusive transport of water into the shale clays and once capillaries are saturated, the cause of micro fracture propagation is the conversion of ionic activity/exchange to excess pressure that did not exist before fracking. Based on these findings, the spread of micro fractures appear to be a time-dependent phenomenon which has not been addressed in the existing macro/micro fracture models.INTRODUCTIONShale has often been involved as a hazard in drilling operations. This hazard can be defined as “destabilization” of shale. When contacted with water-based drilling fluids, some shales readily swell and sometimes, cause the wellbore to cave-in, slough, wash-out, close, and pack-off, impeding the drilling by sticking the drill-pipe. However, once drilling reaches the desired depth or length, the casing is set, cemented, and perforated, and then actually we wish to initiate fractures and destabilize the shale formation, using hydraulic fracturing.Clays constitute a major portion of minerals in shale. These clays contain a large amount of free energy which is the main factor for “slick” water adsorption/absorption. In fact, the reason for using “surfactants” in hydraulic fracturing fluids is to make the penetration of the fluid into the capillaries much easier, thus water meets with less resistance to enter the small capillaries. Also, the result of high capillary suction pressure is due to small Angstrom size capillaries, smaller pores and presence of ions and hydrateable metal atoms. The free energy is thus, related to all the above mentioned and other affects. Capillary pressure, osmotic pressure and other pressures are responsible for creating the micro-fractures in shale, thus, increasing the network of micro-fractures which leads to more gas production. The objective of this study is to evaluate the pressures of the individual ions which are released by the diffusing “slick” water into shale. These pressures would be added to the above mentioned capillary pressure, osmotic pressure, bacterially-induced pressures, chemically-induced reaction pressure, pressure due to exchangeable ion-transport, pressure due to release of free energy of solvation and eventually to the pore pressure as suggested by Terzaghi’s equation."

Jan 1, 2015

By I. A. Kovalevska

Considered problems: elaboration and implementation of resource-saving technologies, low-cost support systems improvement, openings security and support, based on wallrock condition control with supreme implication into the rock pressure occurrence counteraction work. Results of analytic and underground investigations using computer simulation of the finite elements in order to calculate stressstrain state of the multivariable geomechanical systems are presented. Solutions of concrete objectives are found using spatial geomechanical model of solid motion around openings, considering real geomechanical parameters formation of support forms with proper conditions of their contact and real mechanical characteristics. Ultimate solutions of resource-saving technologies implementation based on the analysis of multivariate vertical, horizontal, and reduced stresses components calculation and also near-contour rock, support bearing components and security constructions movements are found. Results of experimental investigations of combined supports and security constructions, which increase openings' stability in difficult conditions of flat coal seams are presented.

Aug 1, 2013

By J. Lipp

The lion share of lithium produced globally originates from South American salars. The standard operation for lithium production utilizes an array of evaporation ponds. This process consume vast areas and is either very slow when relying on solar evaporation - roughly 18 months of residence time; or with very high energy consumption since over 90% of initial water volume needs to be evaporated. A new technology, based on solvent extraction was developed. Results indicate a distribution coefficient up to 30, and selectivity greater than 1,000 towards Na extraction. The loaded solvent is stripped using a strong mineral acid, and the product solution is the lithium derivative of that stripping acid. Utilization of this new LiSXTM technology results in reducing the area needed for a commercial plant as well as reduces the residence time. In addition applying different stripping acids can diversify the product line of such facility.

Jan 1, 2014

By S. Steinlechner, G. Schneeberger, J. Antrekowitsch

Due to always getting stricter environmental legislations as well as increasing land filling fees the efforts for treating residues from metallurgy are continuously increasing. In case of filter dusts from metallurgical industry, the high zinc bearing electric arc furnace (EAF) dusts or also dusts from secondary copper industry are important sources for the recovery of secondary zinc oxide. Because of low capacities for secondary zinc concentrates (like Waelz oxide) in primary zinc metallurgy, the upgrade of such concentrates to a quality that meets the requirements of high quality (technical) zinc oxide becomes more and more important. This would open the opportunity to break into new markets and use it for example directly in electrolytic galvanizing. Therefore this paper will summarize possibilities for an elimination of halogens from secondary zinc oxides. Furthermore selective volatilization trials, with a synthetic mixture according to the analysis of Waelz oxide, were carried out to remove impurities to achieve an upgraded product quality.

Jan 1, 2011

"Dry crushing trials at pilot scale have shown that the IMPTEC Super-fine Crusher has the capacity to generate ultra-fine products from hard mineral assemblages presenting at either coarse or fine feed sizes. The super-fine crusher was introduced at the 27th International Mineral Processing Congress in Santiago Chile, with results from a range of duties, which demonstrated the crusher’s potentially expansive operating scope. This paper focuses on current preparations to progress the technology from pilot scale to commercial scale within a concrete production plant, where lead blast furnace slag will be crushed to ultrafine sizes to generate an active silica product for use as a supplementary cementitious material, which can replace Ordinary Portland Cement. A key objective of the operation is to demonstrate an economical route to reducing the cost of concrete production, improving concrete quality and reducing greenhouse gas emissions. The paper also highlights the potentially key contribution super-fine crushing can make to the long-term viability of iron ore beneficiation by simplifying comminution flow-sheets and reducing operating costs. There is every indication that the technology has the potential to feature universally in metalliferous and industrial mineral flow-sheets. INTRODUCTIONToday’s IMPTEC super-fine crusher is the successful end product of development work over 19 years and is the third particle size reduction device conceived, built and tested over that time. The concept evolved as engineering design progressively developed a mechanism capable of harnessing a highly efficient combination of fundamental particle breakage mechanisms. Early development trials at pilot scale indicated that super-fine crushing had the potential to establish a wet or dry, media free, low energy route to ultra- fine products from hard mineral assemblages. Having achieved some impressive results from open circuit pilot tests on fly ash and granulated blast furnace slag it became clear that the cement industry may well provide opportunities to apply the technology commercially. Following expressions of interest from local cement and concrete plant operators, IMPTEC negotiated an agreement to undertake commercial trials with a SFC 350 super-fine crusher installed on site at a concrete supply plant in South Australia. Super-fine crushing scope was recently expanded following further expressions of interest from research groups involved in the processing of iron ores. Pilot trials are progressing in these areas."

Jan 1, 2016

By Freislich. M., Y. Gordon

"In the changing global market scenario for raw materials for the steel industry, a number of novel iron- and steelmaking process technologies are being developed to provide the steel companies with economically-sustainable alternatives for iron- and steel-making. In addition, the steel industry is also focusing on reduction of energy consumption as well as green-house gas (GHG) emissions to address the crucial subject of climate change. In this context, it is important to assess these critical issues for the alternate iron- and steelmaking technologies that have been developed. This paper presents a comparative evaluation of energy-efficiency and GHG emissions for some selected iron- and steelmaking technologies that are being considered for implementation. In this work, Hatch’s G-CAP™ and En-MAP™ tools that were developed with the main objective of quantifying and qualifying the potential energy savings and CO2 abatement within the iron and steel industry, were employed in the evaluation conducted. INTRODUCTIONThe iron and steel industry continues to transform itself and evolve in the ever-changing global market place – the raw material scenario is constantly changing with respect to quality and quantity (availability), there is stiff competition in both global and local markets, and there is increasing pressure to address global climate change issues, especially since the steel industry is highly energy- and carbonintensive. There is growing importance of steel production in developing countries such as China and India – this means that the steel industry in these countries will play an important role in defining and shaping the future of the industry.Climate change is expected to present new risks to the steel industry with respect to ensuring a sustainable business. Legislators are proposing to limit GHG emission by placing an implicit price on CO2 emission - market-based “cap and trade”, carbon tax etc.. In this scenario, it is important for the steel companies to reduce exposure to climate-related risks and at the same time, find business opportunities within these risks. Thus, there is a need to strategically manage the climate change risks; the key steps to strategically manage climate change risks are presented in Table 1[1]."

Jan 1, 2012

"The content of production reports has its origins in raw measurements taken in harsh production environments. The ensuing measurement/estimation errors always affect reproducibility such that, regardless of the fact that they are balanced through statistical data reconciliation, reported numbers are simply the most probable values of inferred probability distributions. This has important implications for how metal recoveries should be monitored and reported. Indeed, in a context where many process optimisation activities are based on small improvements in recovery, there should be no doubt that inadequate handling of measurement/estimation errors can easily exaggerate or mask actual changes in process performance. However, estimates of the reproducibility of reported metal recoveries are rarely reported to plant management. This situation persists despite the fact that a code compliant metal accounting system must inform management about business risks related to metal accounting. To this extent, this paper focuses on the continuous management of reproducibility level of metal recoveries in compliance with the best practices. Sensitivity analysis of primary and secondary metal accounting models is performed to show the resulting probability distributions for metal recoveries. Some guidelines are given for designing and managing metal accounting systems capable of achieving and sustaining predefined levels for the reproducibility of metal recoveries.INTRODUCTIONEach and every mineral processing plant produces daily, weekly and monthly production reports in which metal balances for payable and penalty elements are presented. While such production reports are usually consulted in offices, underlying raw measurements are taken in harsh production environments where mechanical vibrations, humidity, corrosion and dust, to name a few, disturb measurement procedures. It is thus no surprise that several authors (Francois-Bongarcon & Gy, 2002; Gaylard, Randolph, & Wortley, 2014; Holmes, 2010; Spangenberg & Minnitt, 2014) have reported pervasive issues related to mass/sampling measurements in the context of mineral processing."

Jan 1, 2016

By I. Lackey

In 2004, Zinifex Budel Zink commenced testing with the objective to increase the precipitation of aluminium in the iron purification stage of its hydrometallurgical zinc circuit, without the use of expensive reagents. Findings from the literature applied to the leach circuit at Zinifex Budel Zink demonstrated that aluminium removal from the leach circuit could be increased by lowering the ferric concentration and acidity in the vessels where jarosite precipitation occurs. An associated increase in copper precipitation was mitigated by limiting the extent to which the ferric concentration was lowered in the vessels where jarosite forms and lowering the ratio of copper to aluminium in the solutions entering these vessels.

Jan 1, 2006

By T. Guan, G. Fu, X. Zhou, L. Deng

"Currently, tailings water is required to be recycled in minerals processing plants. When the flotation tailings water of complex copper-sulfur-tungsten polymetallic ore is reused to the flotation of copper-sulfur ore, a portion of tungsten would be lost in copper concentrate or sulfur concentrate due to the addition of the collectors used for oxidized ore which are also effective for the sulfide minerals in the process of tungsten flotation. At the same time, the technical index of copper concentrate and sulfur concentrate would be seriously affected by tailings water. Our experimental researches of many years show that the copper concentrate with a grade of 18.36% Cu at a recovery of 76.67% is obtained for the raw ore containing 0.60% Cu, 18.99% S, 0.16% WO3 in small locked cycle test using recycled water, through simple pretreatment of the tailings water from tungsten flotation and adding special regulator CW and new tungsten collector TM. The result is close to the performance without using tailings water. And, in the continuous pilot experiment which was continuously conducted for 4 days with the same technology, the following results was obtained: the copper concentrate with a grade of 21.74% Cu, the recovery was 71.55%; the sulfur concentrate with a grade of 45.16% S, the recovery was 80.10%; the tungsten concentrate with a grade of 42.63% WO3, the recovery was 54.62% relative to raw ore (the recovery relative to scheelite was 76.47%). The throughput of the continuous pilot experiment is 1.0~1.2 t/d, and the raw ore contains 0.56% Cu, 18.80% S, 0.14% WO3 on average.INTRODUCTIONMining industry is one of the most important developing fields, it supplies raw materials for industrial production as well as discharges much waste water. Tailings water is the main source of beneficiation waste water, it would result in severe environmental pollution if discharged directly. Generally, the tailings water would bring undesirable effect on flotation index after simple pretreatment by lime (Kalin, Fyson, & Wheeler, 2006). On the other hand, the treatment of tailings water through ion-exchange (Cui & Liu, 2015) before recycling is of high cost. Generally, in the flotation of Cu-S-W polymetallic ore, when the tailings water from tungsten flotation is treated simply by lime and recycled to the flotation of sulfide minerals, the flotation index of sulfide minerals decreases, and a portion of oxide mineral would be lost in the sulfide concentrate. As a result, the recycle rate of this kind of tailings water is relatively low, some of the tailings water is discharged after simple treatment and then environmental pollution is caused subsequently. One of the effective ways to improve beneficiation performance and increase the recycle rate of tailings water is to conduct research on developing recycle technology for flotation tailings water of complex copper-sulfur-tungsten polymetallic ore."

Jan 1, 2016

By W. A. Jankola, M. T. Martin

"The world's first zinc pressure leaching plant at Cominco's Trail operations started production in 1981. Sullivan zinc concentrate is leached at the rate of 190 tpd in a four-compartment autoclave at elevated temperatures and oxygen pressures to produce a zinc sulphate solution and elemental sulphur. Zinc extraction exceeds 98% and sulphide to elemental sulphur conversion exceeds 95%.The sulphur is recovered from the discharged slurry in the underflow of a hydrocyclone, and is upgraded as a flotation concentrate. The concentrate is dewatered, melted and filtered to produce a polished sulphur product of better than 99% purity. An alternative sulphur recovery process employs an unique sulphur separation method that recovers over 90% of the sulphur in the molten state. The remaining sulphur is recovered by flotation following flash discharge of the slurry. The product slurry containing the zinc sulphate solution and the iron-lead residue joins the existing roast-leach zinc plant for purification and zinc electrowinning.IntroductionIn 1981, Cominco Ltd. commissioned the world's first commercial zinc pressure leaching plant at their Trail operations in British Columbia. As part of a $700 million modernization and expansion program for lead and zinc started in 1977, the company installed the first o f two autoclave trains.Prior to pressure leaching, zinc production was closely tied to acid and fertilizer production. Sulphur dioxide produced from roasting the concentrates had to be converted to sulphuric acid. Thus, any expansion of zinc operations with the roast-leach technology would have required extensive modifications to the acid and fertilizer plants as well as to the roasters. Zinc pressure leaching, on the other hand, offered a one-step dissolution of zinc from the concentrates with high extraction, and production of elemental sulphur. The associated dust and sulphur dioxide generated in the roasting process are both eliminated from the working environment of the pressure leach facility. The flexibility allowed by producing elemental sulphur, and the opportunity to break the sulphuric acid link for about 25 per cent of the targeted 272,000 tonnes per year zinc production was very appealing. The process was successfully demonstrated at a pilot plant in 1977(1-6)."

Jan 1, 1985

By Ed Labelle, Terry Overton, Gary Bell

"LocationThe Miller Minerals lime and limestone production facility is located in the Temiskaming district of Ontario at Hailey bury on the west shore of Lake Temiskaming. Located less than 300 km from Sudbury, Timmins, Rouyn-Noranda and Val d'Or, the plant is very well situated to market products to the mining, pulp and paper, and environmental industries. Being located a few kilometres from the Trans-Canada Highway and the Ontario Northland Railway adds to transportation efficiencies.ProductsAt Miller Minerals, two principal products in various sizes are produced, which are limestone (CaC03) and quicklime (CaO).HistoryProduction of limestone products began in 1979 at this quarry site. During the 1980s, limestone products were marketed to a variety of applications for mining, forestry, environmental and agriculture applications. In 1990, the production of quicklime products began, following the commissioning of an Italian-designed vertical shaft calcining plant. During the 1990s, both quicklime and limestone products were produced to meet the customers' demands.From the quarry's conception until 1992, the operation was owned and operated by Dymond Clay Products. In 1992, it was purchased by Miller Paving Ltd. of Markham, Ontario, and became a key part of the company's industrial minerals sector of business. Other Miller interests include dolomite, cement, paving materials and waste management."

Jan 1, 2000

By Robert Halupka

The industrial minerals sector represents a broad range of products involving a variety of technologies serving a diversity of markets and end uses. Unit values of products vary widely, reflecting the peculiarities of each product/market sector. Generalizations are therefore understandably difficult to make and borrowers may need to take extra time to "educate" lenders on the key aspects of their business and industry sub-sector. This paper will examine the factors and the thinking that lenders apply when considering financing proposals to companies in the industrial minerals sector. If you understand the lender's perspective and their concerns, then you can make better use of your own time and resources when arranging financing for your company or project.

Jan 1, 2001

By T. V. Lord

Minerals containing uranium have been successfully pre-concentrated by flotation at Queen's University, Kingston. In particular, uraninite, uranothorite, euxenite, and fergusonite, have responded to flotation to yield grades of 0.2 to 6.0 .per cent U .o. with recoveries of 85 to 98 per cent, from heads analysing approximately 0.10 per cent U3Os. Of the ten or so radioactive samples examined to date, two distinct groups were recognizable, firstly, those samples in which uranium was the sole constituent of economic interest, and, secondly, those in which Columbium (with minor amount of tantalum) was present in addition to uranium. For the purpose of this paper, the results of investigation on two samples of each of the above groups have been selected as typical.

Jan 1, 1945

By S. Goodman

Successful exploration for and exploitation of a mineral deposit requires an accurate understanding of the deposit architecture in 3D, and of the development of the mineralizing system through time, which requires a thorough comprehension of the structural framework of the deposit. The integration of geological, geophysical and geochemical datasets to arrive at a 4D structural framework is well-established and has been successfully applied by SRK Consulting in projects from deposit to regional scale. In some cases, we can go beyond this, applying the SEEBASETM technique, which utilizes a ?bottom-up? approach to basin analysis. SRK?s approach primarily relies on the interpretation of magnetic and gravity data, calibrated with many other datasets including mapped geology, topography, event histories, wells/drillholes and seismic data. The SEEBASETM model is a culmination of this data integration and is produced through an iterative process of structural interpretation and geophysical modeling, where an interpretation of basement composition and 4D structure is used to constrain depth-to-basement geophysical modeling, and the modeled depths are then used in conjunction with the structural interpretation to constrain contouring of the basement topography. The result is a rigorously calibrated, 3D view of the basement surface, which can be used to understand the basement and basin architecture, and thus serves as a predictive exploration model. This technique, which was developed for use in the petroleum industry, is now finding success as a predictive tool in mineral exploration.

May 1, 2003

By C. J. Sullivan

Many metalliferous ?provinces are co-extensive with particular groups of sedimentary, volcanic, or :basic plutonic rocks. Deposits may be truly syngenetic (Rand, Rhodesia-Katanga, Mans-field, Blind River, White Pine); re-. concentrated by circulating waters (Colorado Plateau, Red Bed Coppers) ; or re-concentrated thermally during metamorphism and granitization (most uranium and lead-zinc provinces ?and some copper and gold provinces). Basalts may yield important cop-per provinces when folded and re-heated. Granitization of basalts which have not reached the chlorite-carbon-ate phase of metamorphism may produce copper provinces. If they reach ?the chlorite-carbonate stage, granitization may result in a gold province. Copper and copper-nickel provinces may result if gabbros are granitized, and a ?similar alteration of per-idotite may result in asbestos or nickel ores. Many similar associations are known. Granite is not a source of ore, but a result of heat. A classification of ?ore with respect to source rocks is of greater prospecting value than are classifications based on magmatic differentiation and hydrother-mal solution theories. Volcanic centres are important ore foci because the thermally unstable metallic sulphides may be concentrated here by a distillation process. The ores found in the hot spring deposits, viz., mercury, mercury sulphide, sulphur, and the compounds of ?antimony and arsenic, are not those which are soluble in water at low temperature (epithermal sub-division of hydrothermal class), abrut those which are unstable thermally at comparatively low temperatures . Water is one of the most common thermally unstable minerals, and generally accompanies the thermally activated ore-forming sulphides.

Jan 1, 1957

By Jared Onyirimba, Jim Viellenave, Hal Demuth, Dale Verran, Chad Sorba, Errol Lawrence, David Bronkhorst

As outlined within the Denison Mines Corp’s (“Denison”) Pre-Feasibility Study ("PFS") completed in late 2018, additional work is required to increase confidence and reduce risk associated with the application of the In-Situ Recovery (“ISR”) mining method at the Phoenix deposit, located on the Wheeler River Uranium Project (“Wheeler River” or the “Project”) in northern Saskatchewan. The successful application of ISR in any geological environment largely hinges on three fundamental requirements, 1) permeability (of the deposit), 2) containment (of the mining solution) and 3) leachability (of the mineralization). Denison has designed several staged technical programs to progressively reduce risk associated with these requirements as the Company advances the Project toward a Feasibility Study (“FS”) and Environmental Impact Assessment (“EIA”). This paper will discuss the scope and results of certain technical programs being undertaken as the Company aims to develop the first ISR mining operation in the Athabasca Basin.

Jan 1, 2020