scholarly journals The Efficiency of Large Hole Boring (MSP) Method in the Reduction of Blast-Induced Vibration

2021 ◽  
Vol 11 (4) ◽  
pp. 1814
Author(s):  
Min Seong Kim ◽  
Sean Seungwon Lee
Keyword(s):  
Urban Areas ◽  
Cost Effective ◽  
Base Case ◽  
Large Hole ◽  
Promising Alternative ◽  
Geological Information ◽  
Drill And Blast ◽  
Smooth Blasting ◽  
Alternative Designs ◽  
Blasting Method

Drill and blast is the most cost-effective excavation method for underground construction, however, vibration and noise, induced by blasting, have been consistently reported as problems. Cut blasting has been widely employed to reduce the blast-induced problems during underground excavation. We propose that the large hole boring method using the state-of-the-art MSP (Multi-setting smart-investigation of the ground and pre-large hole boring) machine (“MSP method”) can efficiently improve vibration reduction. The MSP machine will be used to create 382 mm diameter empty holes at the tunnel cut area for this purpose. This study assessed the efficiency of the MSP method in reducing blast-induced vibration in five blasting patterns using a cylinder-cut, which is a traditional cut blasting method. The controlled blasting patterns using the MSP method demonstrated up to 72% reduction in blast-induced vibration, compared to the base case, Pattern B, where only cylinder-cut and smooth blasting method were applied. Therefore, the MSP method proves to be a promising alternative for blasting in sensitive urban areas where non-vibration excavation techniques were initially considered. Geological characteristics of 50 m beyond the excavation face can be acquired through the proposed real-time boring data monitoring system together with a borehole alignment tracking and ground exploration system. The obtained geological information will be a great help in preparing alternative designs, and scheduling of construction equipment and labour during the tunnel construction.

Efficient Schedule of Energy-Constrained UAV Using Crowdsourced Buses in Last-Mile Parcel Delivery

2021 ◽  
Vol 5 (1) ◽  
pp. 1-23
Author(s):  
Yan Pan ◽  
Shining Li ◽  
Qianwu Chen ◽  
Nan Zhang ◽  
Tao Cheng ◽  
...  
Keyword(s):  
Traffic Congestion ◽  
Large Scale ◽  
Load Capacity ◽  
Scheduling Algorithm ◽  
Cost Effective ◽  
Promising Alternative ◽  
Logistics Industry ◽  
Last Mile ◽  
Delivery Scheduling ◽  
Schedule Approach

Stimulated by the dramatical service demand in the logistics industry, logistics trucks employed in last-mile parcel delivery bring critical public concerns, such as heavy cost burden, traffic congestion and air pollution. Unmanned Aerial Vehicles (UAVs) are a promising alternative tool in last-mile delivery, which is however limited by insufficient flight range and load capacity. This paper presents an innovative energy-limited logistics UAV schedule approach using crowdsourced buses. Specifically, when one UAV delivers a parcel, it first lands on a crowdsourced social bus to parcel destination, gets recharged by the wireless recharger deployed on the bus, and then flies from the bus to the parcel destination. This novel approach not only increases the delivery range and load capacity of battery-limited UAVs, but is also much more cost-effective and environment-friendly than traditional methods. New challenges therefore emerge as the buses with spatiotemporal mobility become the bottleneck during delivery. By landing on buses, an Energy-Neutral Flight Principle and a delivery scheduling algorithm are proposed for the UAVs. Using the Energy-Neutral Flight Principle, each UAV can plan a flying path without depleting energy given buses with uncertain velocities. Besides, the delivery scheduling algorithm optimizes the delivery time and number of delivered parcels given warehouse location, logistics UAVs, parcel locations and buses. Comprehensive evaluations using a large-scale bus dataset demonstrate the superiority of the innovative logistics UAV schedule approach.

scholarly journals Cost-effectiveness analysis of ranibizumab for retinal vein occlusion patients in China from the societal perspective

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Weiyi Ni ◽  
Jia Liu ◽  
Yawen Jiang ◽  
Jing Wu
Keyword(s):  
Cost Effectiveness ◽  
Retinal Vein Occlusion ◽  
Societal Perspective ◽  
Laser Photocoagulation ◽  
Cost Effective ◽  
Sensitivity Analyses ◽  
Gdp Per Capita ◽  
Base Case ◽  
Vein Occlusion ◽  
Per Capita

Abstract Background Clinical trials in China have demonstrated that ranibizumab can improve the clinical outcomes of branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO). However, no economic evaluation of ranibizumab has been conducted among Chinese patient population. Methods To provide insights into the economic profile of ranibizumab among Chinese RVO population, a Markov state-transition model was used to predict the outcomes of ranibizumab comparing to laser photocoagulation and observational-only care from the societal perspective. This model simulated changes in patient visuality, quality-adjusted of life years (QALY), medical costs, and direct non-medical costs of individuals with visual impairment due to BRVO or CRVO in lifetime. The base-case analysis used an annual discount rate of 5% for costs and benefits following the China Guidelines for Pharmacoeconomic Evaluations. Deterministic and probabilistic sensitivity analyses were performed to test the robustness of the model. Results The base-case incremental cost-effectiveness ratio (ICER) comparing ranibizumab to laser photocoagulation was ¥65,008/QALY among BRVO patients and was ¥65,815/QALY among CRVO patients, respectively. Comparing to the 2019 gross domestic product (GDP) per capita of ¥71,000, both two ICERs were far below the cost-effective threshold at three times of GDP per capita (¥213,000). The deterministic and probabilistic sensitivity analyses demonstrated the base-case results were robust in most of the simulation scenarios. Conclusion The current Markov model demonstrated that ranibizumab may be cost-effective compared with laser photocoagulation to treat BRVO and cost-effective compared to observation-only care to treat CRVO in China from the societal perspective.

scholarly journals Prenatal Nutritional Strategies to Reduce the Risk of Preterm Birth

2021 ◽  
pp. 1-9
Author(s):  
Karen Patricia Best ◽  
Judith Gomersall ◽  
Maria Makrides
Keyword(s):  
Preterm Birth ◽  
Large Scale ◽  
Cochrane Review ◽  
Cost Effective ◽  
Omega 3 ◽  
Promising Alternative ◽  
Nutritional Interventions ◽  
Dietary Nutrients ◽  
Preterm Babies ◽  
Nutritional Strategies

Worldwide, around 15 million preterm babies are born annually, and despite intensive research, the specific mechanisms triggering preterm birth (PTB) remain unclear. Cost-effective primary prevention strategies to reduce PTB are required, and nutritional interventions offer a promising alternative. Nutrients contribute to a variety of mechanisms that are potentially important to preterm delivery, such as infection, inflammation, oxidative stress, and muscle contractility. Several observational studies have explored the association between dietary nutrients and/or dietary patterns and PTB, often with contrasting results. Randomized trial evidence on the effects of supplementation with zinc, multiple micronutrients (iron and folic acid), and vitamin D is promising; however, results are inconsistent, and many studies are not adequately powered for outcomes of PTB. Large-scale clinical trials with PTB as the primary outcome are needed before any firm conclusions can be drawn for these nutrients. The strongest evidence to date for a nutritional solution exists for omega-3 long-chain polyunsaturated fatty acids (LCPUFAs), key nutrients in fish. In 2018, a Cochrane Review (including 70 studies) showed that prenatal supplementation with omega-3 LCPUFAs reduced the risk of PTB and early PTB (EPTB) compared with no omega-3 supplementation. However, the largest trial of omega-3 supplementation in pregnancy, the Omega-3 to Reduce the Incidence of Prematurity (ORIP) trial (<i>n</i> = 5,544), showed no reduction in EPTB and a reduction in PTB only in a prespecified analysis of singleton pregnancies. Exploratory analyses from the ORIP trial found that women with low baseline total omega-3 status were at higher risk of EPTB, and that this risk was substantially reduced with omega-3 supplementation. In contrast, women with replete or high baseline total omega-3 status were already at low risk of EPTB and additional omega-3 supplementation increased the risk of EPTB compared to control. These findings suggest that determining an individual woman’s PUFA status may be the most precise way to inform recommendations to reduce her risk of PTB.

Evaluation of Strategies to Mitigate Culvert-Involved Crashes

2021 ◽  
pp. 036119812199207
Author(s):  
Hitesh Chawla ◽  
Megat-Usamah Megat-Johari ◽  
Peter T. Savolainen ◽  
Christopher M. Day
Keyword(s):  
Negative Binomial ◽  
Negative Binomial Regression ◽  
Cost Effective ◽  
Negative Binomial Regression Model ◽  
Promising Alternative ◽  
Roadside Safety ◽  
Adverse Conditions ◽  
Traffic Characteristics ◽  
Annual Average Daily Traffic ◽  
Binomial Regression

The objectives of this study were to assess the in-service safety performance of roadside culverts and evaluate the potential impacts of installing various safety treatments to mitigate the severity of culvert-involved crashes. Such crashes were identified using standard fields on police crash report forms, as well as through a review of pertinent keywords from the narrative section of these forms. These crashes were then linked to the nearest cross-drainage culvert, which was associated with the nearest road segment. A negative binomial regression model was then estimated to discern how the risk of culvert-involved crashes varied as a function of annual average daily traffic, speed limit, number of travel lanes, and culvert size and offset. The second stage of the analysis involved the use of the Roadside Safety Analysis Program to estimate the expected crash costs associated with various design contexts. A series of scenarios were evaluated, culminating in guidance as to the most cost-effective treatments for different combinations of roadway geometric and traffic characteristics. The results of this study provide an empirical model that can be used to predict the risk of culvert-involved crashes under various scenarios. The findings also suggest that the installation of safety grates on culvert openings provides a promising alternative for most of the cases where the culvert is located within the clear zone. In general, a guardrail is recommended when adverse conditions are present or when other treatments are not feasible at a specific location.

scholarly journals OutFin, a multi-device and multi-modal dataset for outdoor localization based on the fingerprinting approach

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Fahad Alhomayani ◽  
Mohammad H. Mahoor
Keyword(s):  
Global Navigation Satellite System ◽  
Urban Areas ◽  
Satellite System ◽  
Reference Points ◽  
Navigation Satellite ◽  
Data Types ◽  
Entry Barrier ◽  
Promising Alternative ◽  
Global Navigation ◽  
Global Navigation Satellite

AbstractIn recent years, fingerprint-based positioning has gained researchers’ attention since it is a promising alternative to the Global Navigation Satellite System and cellular network-based localization in urban areas. Despite this, the lack of publicly available datasets that researchers can use to develop, evaluate, and compare fingerprint-based positioning solutions constitutes a high entry barrier for studies. As an effort to overcome this barrier and foster new research efforts, this paper presents OutFin, a novel dataset of outdoor location fingerprints that were collected using two different smartphones. OutFin is comprised of diverse data types such as WiFi, Bluetooth, and cellular signal strengths, in addition to measurements from various sensors including the magnetometer, accelerometer, gyroscope, barometer, and ambient light sensor. The collection area spanned four dispersed sites with a total of 122 reference points. Each site is different in terms of its visibility to the Global Navigation Satellite System and reference points’ number, arrangement, and spacing. Before OutFin was made available to the public, several experiments were conducted to validate its technical quality.

scholarly journals Biomimicry-Based Strategies for Urban Heat Island Mitigation: A Numerical Case Study under Tropical Climate

Biomimetics ◽  
2021 ◽  
Vol 6 (3) ◽  
pp. 48
Author(s):  
Kevin Araque ◽  
Paola Palacios ◽  
Dafni Mora ◽  
Miguel Chen Austin
Keyword(s):  
Thermal Comfort ◽  
Urban Heat Island ◽  
Urban Areas ◽  
Outdoor Thermal Comfort ◽  
Base Case ◽  
Heat Island ◽  
Urban Heat ◽  
Historical Heritage ◽  
Pet Index ◽  
Radiant Temperature

In recent years, demographic growth has caused cities to expand their urban areas, increasing the risk of overheating, creating insurmountable microclimatic conditions within the urban area, which is why studies have been carried out on the urban heat island effect (UHI) and its mitigation. Therefore, this research aims to evaluate the cooling potential in the application of strategies based on biomimicry for the microclimate in a historical heritage city of Panama. For this, three case studies (base case, case 1, and case 2) of outdoor thermal comfort were evaluated, in which the Envi-met software was used to emulate and evaluate the thermal performance of these strategies during March (highest temperature month) and October (rainier month). The strategies used were extracted from the contrast of zebra skin, human skin, evaporative cooling, and ant skin. The results showed a reduction of 2.8 °C in the air temperature at 11:00, the radiant temperature decreased by 2.2 °C, and the PET index managed to reduce the thermal comfort indicator among its categories. The importance of thinking based on biomimicry in sustainable strategies is concluded; although significant changes were obtained, high risks of discomfort persist due to the layout and proximity of the building.

Selecting Sanitation Solutions for Peri-urban Areas: A Case Study of Can Tho, Vietnam

2010 ◽  
Vol 5 (4) ◽  
Author(s):  
Naomi Carrard ◽  
Juliet Willetts ◽  
Cynthia Mitchell ◽  
Mick Paddon ◽  
Monique Retamal
Keyword(s):  
Urban Areas ◽  
Cost Effective ◽  
Asset Replacement ◽  
Fit For Purpose ◽  
Infrastructure Investments ◽  
Sanitation Systems ◽  
Can Tho City ◽  
Sustainable Futures ◽  
Sanitation Infrastructure ◽  
Selection Of

In peri-urban areas where infrastructure investments have not yet been made, there is a need to determine the most context-appropriate, fit for purpose and sustainable sanitation solutions. Decision makers must identify the optimal system scale (on the spectrum from centralized to community to cluster scale) and assess the long-term costs and socio-economic/environmental impacts associated with different options. Addressing both cost-effectiveness and sustainability are essential to ensure that institutions and communities are able to continue to bear the costs and management burden of infrastructure operation, maintenance and asset replacement. This paper describes an approach to sanitation planning currently being undertaken as a research study in Can Tho City in southern Vietnam, by the Institute for Sustainable Futures and Can Tho University in collaboration with Can Tho Water Supply and Sewerage Company. The aim of the study is to facilitate selection of the most context-appropriate, fit for purpose, cost effective and sustainable sanitation infrastructure solution. As such, the study compares a range of sanitation alternatives including centralized, decentralized (at household or cluster scale) and resource recovery options. This paper provides an overview of the study and considers aspects of the Can Tho and Vietnamese regulatory, development and institutional context that present drivers and challenges for comparison of options and selection of fit for purpose sanitation systems.

scholarly journals Economic evaluation of robot-assisted radical prostatectomy compared to open radical prostatectomy for prostate cancer treatment in Ontario, Canada

2020 ◽  
Vol 14 (8) ◽  
Author(s):  
Anna Parackal ◽  
Jean-Eric Tarride ◽  
Feng Xie ◽  
Gord Blackhouse ◽  
Jennifer Hoogenes ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Radical Prostatectomy ◽  
Time Horizon ◽  
Cost Effective ◽  
Cost Utility ◽  
Economic Evaluations ◽  
Base Case ◽  
Robot Assisted ◽  
Open Radical Prostatectomy ◽  
Life Years

Introduction: Recent health technology assessments (HTAs) of robot-assisted radical prostatectomy (RARP) in Ontario and Alberta, Canada, resulted in opposite recommendations, calling into question whether benefits of RARP offset the upfront investment. Therefore, the study objectives were to conduct a cost-utility analysis from a Canadian public payer perspective to determine the cost-effectiveness of RARP. Methods: Using a 10-year time horizon, a five-state Markov model was developed to compare RARP to open radical prostatectomy (ORP). Clinical parameters were derived from Canadian observational studies and a recently published systematic review. Costs, resource utilization, and utility values from recent Canadian sources were used to populate the model. Results were presented in terms of increment costs per quality-adjusted life years (QALYs) gained. A probabilistic analysis was conducted, and uncertainty was represented using cost-effectiveness acceptability curves (CEACs). One-way sensitivity analyses were also conducted. Future costs and QALYs were discounted at 1.5%. Results: Total cost of RARP and ORP were $47 033 and $45 332, respectively. Total estimated QALYs were 7.2047 and 7.1385 for RARP and ORP, respectively. The estimated incremental cost-utility ratio (ICUR) was $25 704 in the base-case analysis. At a willingness-to-pay threshold of $50 000 and $100 000 per QALY gained, the probability of RARP being cost-effective was 0.65 and 0.85, respectively. The model was most sensitive to the time horizon. Conclusions: The results of this analysis suggest that RARP is likely to be cost-effective in this Canadian patient population. The results are consistent with Alberta’s HTA recommendation and other economic evaluations, but challenges Ontario’s reimbursement decision.

scholarly journals The effects of global changes upon regional ozone pollution in the United States

2009 ◽  
Vol 9 (4) ◽  
pp. 1125-1141 ◽  
Author(s):  
J. Chen ◽  
J. Avise ◽  
B. Lamb ◽  
E. Salathé ◽  
C. Mass ◽  
...  
Keyword(s):  
Urban Areas ◽  
The United States ◽  
Base Case ◽  
Global Changes ◽  
Ozone Pollution ◽  
Modeling Framework ◽  
Voc Emissions ◽  
The Us ◽  
The Future ◽  
Future Case

Abstract. A comprehensive numerical modeling framework was developed to estimate the effects of collective global changes upon ozone pollution in the US in 2050. The framework consists of the global climate and chemistry models, PCM (Parallel Climate Model) and MOZART-2 (Model for Ozone and Related Chemical Tracers v.2), coupled with regional meteorology and chemistry models, MM5 (Mesoscale Meteorological model) and CMAQ (Community Multi-scale Air Quality model). The modeling system was applied for two 10-year simulations: 1990–1999 as a present-day base case and 2045–2054 as a future case. For the current decade, the daily maximum 8-h moving average (DM8H) ozone mixing ratio distributions for spring, summer and fall showed good agreement with observations. The future case simulation followed the Intergovernmental Panel on Climate Change (IPCC) A2 scenario together with business-as-usual US emission projections and projected alterations in land use, land cover (LULC) due to urban expansion and changes in vegetation. For these projections, US anthropogenic NOx (NO+NO2) and VOC (volatile organic carbon) emissions increased by approximately 6% and 50%, respectively, while biogenic VOC emissions decreased, in spite of warmer temperatures, due to decreases in forested lands and expansion of croplands, grasslands and urban areas. A stochastic model for wildfire emissions was applied that projected 25% higher VOC emissions in the future. For the global and US emission projection used here, regional ozone pollution becomes worse in the 2045–2054 period for all months. Annually, the mean DM8H ozone was projected to increase by 9.6 ppbv (22%). The changes were higher in the spring and winter (25%) and smaller in the summer (17%). The area affected by elevated ozone within the US continent was projected to increase; areas with levels exceeding the 75 ppbv ozone standard at least once a year increased by 38%. In addition, the length of the ozone season was projected to increase with more pollution episodes in the spring and fall. For selected urban areas, the system projected a higher number of pollution events per year and these events had more consecutive days when DM8H ozone exceed 75 ppbv.

Cost-effectiveness of dual-mobility components in patients with displaced femoral neck fractures

2021 ◽  
Vol 103-B (12) ◽  
pp. 1783-1790
Author(s):  
Spencer Montgomery ◽  
Jonathan Bourget-Murray ◽  
Daniel Z. You ◽  
Leo Nherera ◽  
Amir Khoshbin ◽  
...  
Keyword(s):  
Sensitivity Analysis ◽  
Cost Effectiveness ◽  
Femoral Neck ◽  
Incremental Cost ◽  
Probabilistic Sensitivity Analysis ◽  
Cost Effective ◽  
Physiological Age ◽  
Base Case ◽  
Dual Mobility ◽  
Displaced Femoral Neck Fractures

Aims Total hip arthroplasty (THA) with dual-mobility components (DM-THA) has been shown to decrease the risk of dislocation in the setting of a displaced neck of femur fracture compared to conventional single-bearing THA (SB-THA). This study assesses if the clinical benefit of a reduced dislocation rate can justify the incremental cost increase of DM-THA compared to SB-THA. Methods Costs and benefits were established for patients aged 75 to 79 years over a five-year time period in the base case from the Canadian Health Payer’s perspective. One-way and probabilistic sensitivity analysis assessed the robustness of the base case model conclusions. Results DM-THA was found to be cost-effective, with an estimated incremental cost-effectiveness ratio (ICER) of CAD $46,556 (£27,074) per quality-adjusted life year (QALY). Sensitivity analysis revealed DM-THA was not cost-effective across all age groups in the first two years. DM-THA becomes cost-effective for those aged under 80 years at time periods from five to 15 years, but was not cost-effective for those aged 80 years and over at any timepoint. To be cost-effective at ten years in the base case, DM-THA must reduce the risk of dislocation compared to SB-THA by at least 62%. Probabilistic sensitivity analysis showed DM-THA was 58% likely to be cost-effective in the base case. Conclusion Treating patients with a displaced femoral neck fracture using DM-THA components may be cost-effective compared to SB-THA in patients aged under 80 years. However, future research will help determine if the modelled rates of adverse events hold true. Surgeons should continue to use clinical judgement and consider individual patients’ physiological age and risk factors for dislocation. Cite this article: Bone Joint J 2021;103-B(12):1783–1790.

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