Construction Duration Research Articles

近20年黄土高原生态系统服务研究进展

PDF HTML阅读 XML下载 导出引用 引用提醒 近20年黄土高原生态系统服务研究进展 DOI: 10.5846/stxb202204291190 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（42041007，42171088）；中央高效基本科研业务费专项资金资助 Research progress on the ecosystem services on the Loess Plateau during the recent 20 years Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:生态系统服务是自然生态系统及其物种提供的供给和维持人类生存的条件和过程，是人类通过生态系统的功能直接或间接得到的产品或服务，具有典型的区域性特征。黄土高原是黄河流域重要生态安全屏障，生态建设规模大、历时长，是我国生态系统服务研究的重要案例区。已有研究针对黄土高原生态系统服务进行物质量与价值量估算、权衡与协同关系识别和供需关系评估，但不同结论之间缺少归纳和对比。研究对近20年来黄土高原地区生态系统服务研究的文献总体特征和主要研究发现分析表明：相关中英文论文数量和被引频次整体呈上升趋势，研究内容上主要关注黄土高原生态系统服务的定量估算，近年来逐渐向生态系统服务权衡分析和供需关系评估拓展；黄土高原地区自退耕还林以来，各项生态系统服务总量呈上升趋势，呈现出东南增量较多、西北增量较少的空间格局；黄土高原地区供给服务和调节服务存在较明显的权衡关系，但在不同尺度上强度分异明显；区域内生态系统服务供给量和需求量均呈增加趋势，供需匹配状况具有明显时空差异。面向当前研究中物质量评估种类不足、价值量估算高度不确定、权衡与协同现象缺乏归因、空间流动性体现不足等问题，未来黄土高原生态系统服务研究有待加强面向生态产品价值实现的生态系统服务价值估算，空间流动视角下的生态系统服务供需关系评估，以及基于生态系统服务权衡情景模拟的国土空间优化。 Abstract:Ecosystem services are the conditions and processes provided by natural ecosystems and their species that supply and sustain human existence, and are products or services that human received directly or indirectly through the functions of ecosystems. It has typically regional characteristics. The Loess Plateau is an important ecological security barrier in the Yellow River Basin, with a large scale and long duration of ecological construction, and is an important case area for ecosystem service research in China. Previous studies have estimated the value and quality of ecosystem services, identified their trade-offs and synergies, and evaluated their supply-demand relationship on the Loess Plateau. However, there is a lack of generalization and comparison among different conclusions. We analysed the main findings of the literature on ecosystem services on the Loess Plateau region over the past 20 years, and got the following results. The number of relevant papers in both English and Chinese have been generally increasing, as well as the frequency of citations. The research content was mainly concerned with the quantitative estimation of ecosystem services on the Loess Plateau, and it has gradually expanded to the analysis of ecosystem service trade-offs and the assessment of supply-demand relationship in recent years. Since the Grain-for-Green project, the vegetation cover of the Loess Plateau has increased and the total amount of ecosystem services has been on the rise, presenting a spatial pattern of more increased in the southeast and less increased in the northwest. There are clear trade-offs between provision and regulation services on the Loess Plateau, and the intensity varies apparently at different scales. Both the supply and demand of ecosystem services are increasing in the region, with clear spatial and temporal differences in their matching degree. To address the limitations of insufficient types of quality assessments, high uncertainty in value estimation, lack of attribution of trade-offs and synergies, and insufficient representation of spatial delivery, future research on ecosystem services on the Loess Plateau needs to strengthen the estimation of ecosystem service values towards the realization of ecological product value, improve the assessment of ecosystem service supply and demand from the perspective of spatial delivery, and enhance the simulation of ecosystem service trade-off scenarios to support territorial space optimization. 参考文献 相似文献 引证文献

Математическая модель оптимального распределения ресурсов в строительной сфере в условиях их дефицита

Logistics in the field of construction is one of its most important components, directly affecting the success of the implementation of construction projects. The problem of the optimal distribution of available limited resources is an important and urgent task in planning and organizing construction work, especially in conditions of scarcity of resources. The solution of this problem directly affects the quality and result of construction projects, the duration and rhythm of construction, costs and labor productivity. Aim. The purpose of the study is to develop a mathematical model based on vector optimization methods that allows optimal distribution of various types of limited resources between construction activities, works or objects in order to increase the efficiency of construction projects. Materials and methods. The model of resource distribution described in the paper is based on the theory of vector linear optimization, which makes it possible to distribute limited resources of various types between works, activities, or construction objects. The model takes into account the minimum and optimal requirements for providing construction objects or works with resources, their supply, as well as the priority for supplying objects. A technique for organizing computational procedures according to the model by numerical methods is given. Simulation methods based on computational experiments substantiate the adequacy of the proposed model and the properties of the results obtained from it. Also, the effectiveness of the implementation of the resource allocation model in the system of planning and management of construction projects was assessed. Results. A mathematical model for the distribution of limited resources between construction objects, works or events has been developed and justified. The adequacy of the results obtained by the model is proved. A technique for carrying out computational procedures for the numerical implementation of the model in the MS Excel environment is described. On the basis of computational experiments, the efficiency of applying the resource allocation model in the management of construction projects was evaluated, which averaged more than 34%. Conclusion. The relevance of developing a model for the distribution of resources of various types in the field of construction is shown, the adequacy of the results is proved, the method for obtaining estimates from the model by numerical methods is described, and the economic effect of applying the model in practice is estimated. The proposed resource allocation model leads to a significant increase in the efficiency of organization and management of construction projects and increases the likelihood of their timely completion at minimal cost.

Estimation of ideal construction duration in tender preparation stage for housing projects

Abstract Despite the potential of various methods for calculating construction duration, few studies have focused on the application of these methods in the tender preparation stage, and even fewer have focused on their application in public housing projects. Moreover, research related to construction duration in Turkey has indicated that considerable delays occur in public housing projects. Therefore, we investigated the factors affecting the construction duration of housing projects and developed a novel calculation method for estimating the ideal construction duration. Data on public housing projects were obtained from a major Turkish construction authority. Statistical data analysis was performed using multiple linear regression analysis, chi-squared automatic interaction detection (CHAID), and classification and regression tree (CART) methods. The results revealed that several factors significantly affected the ideal construction duration for each statistical method. The cutoffs and standard errors were calculated to test the validity of all three statistical methods. The regression formula indicated statistical significance when the calculation method was tested. The implementation of the methods for other public housing projects significantly reduced the number of delayed projects. The findings of this study are expected to contribute by way of enabling senior project managers to estimate the ideal construction duration for housing projects during the tender preparation stage.

Research on construction duration coordination of complex equipment remanufacturing supply chain under dual time uncertainty

Research on construction duration coordination of complex equipment remanufacturing supply chain under dual time uncertainty

Research on construction duration coordination of complex equipment remanufacturing supply chain under dual time uncertainty

Research on construction duration coordination of complex equipment remanufacturing supply chain under dual time uncertainty

Optimal procurement strategy for off-site prefabricated components considering construction schedule and cost

The implementation of prefabricated buildings is hindered by the high construction cost. To address this problem, it is important to determine the efficient leverage of the supply capacity of local factories to assure just-in-time delivery to the construction site, as well as to accurately model the various types of cost to achieve a near-optimal procurement strategy. This paper describes a mathematical model to optimize the procurement of prefabricated components. A genetic algorithm is applied to efficiently obtain the minimum total cost that includes installation cost, business management cost and loan interest cost. Finally, a number of numerical experiments are conducted, showing that the procurement strategy generated from the proposed mathematical model is better than the traditional procurement strategy in terms of construction duration reductions and total cost savings. The component procurement method proposed in this paper improves the scientific management ability of decision-makers, and provides purchasing framework for other prefabricated structural forms.

Study on Construction Molding Technology of Long-Span Space Truss Suspended Dome Structure

Typically, the upper part of the roof a gymnasium building is a radial inverted triangular truss structure, and the lower part is a cable structure. They are connected by vertical braces to form a self-balancing structural system. The whole roof is supported by a complex, spatial, prestressed structure comprising tilted Y-shaped laced columns. Such structures rely on the integrity of the form and the application of prestress to achieve the best performance; it is in an extremely unstable state during construction. In order to study the mechanical behavior of the structure in this process, finite element software was used to analyze the cumulative slip of the structure and the construction process of cable tension, and the simulation values were compared to the actual monitoring values. The stress and deformation of the structure in different construction stages were investigated, and a reasonable structural unloading scheme was put forward. The study results showed that the stiffness of the long-span space truss suspended dome structure gradually increased with the structural integrity during construction, and the vertical deformation decreased from 25.4 mm to 19.26 mm with the construction process. The location and magnitude of the structure’s maximum internal force and maximum stress varied greatly compared to the static analysis when considering the construction process effects. Hence, conducting a construction process analysis is necessary. The construction technology of symmetrical rotating cumulative slip proposed in this paper has the advantages of a short construction duration, safe and stable construction process, etc., providing technical references for similar engineering constructions.

Effect of steam‒curing on the glass fiber reinforced concrete

Due to the increased need to use precast concrete to reduce construction duration and to accelerate the cement reaction process to achieve the required concrete resistance that enables the elements to gain the required strength to handle the loads generated by the transportation process, many companies use steam curing methods to expedite the hydration process. The steam curing process negatively affects the concrete strength, especially in the long term. Fibers of different types are used to improve the interior composition of concrete and increase its crack resistance. The purpose of the current study was to determine the effect of the glass fiber on the behavior of steam-cured concrete. In this study 90 concrete cubes were used with 15cm dimensions, three different weight ratios of glass fibers (0%, 0.12%, and 0.24%) with two curing methods standard curing in the water tank (water curing - WC) for 3, 7, and 28 days, and steam curing (SC) for 4 and 8 hours. Nine specimens of each mix were cast in 12 mm, and 24 mm fibers length and tested for each curing duration and method. The results of this study indicate that fiber glass addition to the steam-cured concrete has a positive effect on the concrete unit weight and the ultrasonic pulse velocity. Moreover, the result showed that the tensile and compressive strength of the concrete has been positively affected by the length of the fiber more than the fiber weight percentage.

Application of project management tool in construction for Planning, Scheduling and Optimization

In India, the number of building construction projects is increasing, with growth expected to reach double digits in Fiscal Year 2022, up from an 8.6 % decrease last year. Time and cost overruns, on the other hand, are important issues in the construction sector due to poor planning. The goal of this study is to determine the impact of typical construction flaws and scheduling errors on construction time and expense overruns. In the present work, the scheduling and estimation of G + 11 building at Pune, Maharashtra has been performed on available project planning software (Microsoft Project (MSP2010) and Wrike). Microsoft Project (MSP) and Wrike software are promoted as excellent project management tools. MSP is a technique for reducing time and expense overruns via proper planning and scheduling. Wrike is used to plan and organizethe building project. Implementation of these planning software is not only results in reduction of construction cost but also allows reduction in construction duration.

Efficiency and optimization of building insulation with the help of facade systems

In the article Selection of optimal technological solutions for the installation of hinged ventilated facades using calculations. Necessary factors are identified, in which the optimal methods of facade insulation, the minimum period of time for installation work and the corresponding cost of materials and works are determined. Optimization of organizational and technological solutions can be achieved due to the limit limitations of design indicators. The solution of this task was carried out using the combination of duration and cost diagrams.
 Minimization of resource costs can be achieved by increasing the number of work teams and working days per week. According to the results of the research, the following parameters of the technological process were recommended for the use of the following parameters of the technological process, provided that the minimum indicators of cost and duration were achieved when installing single-layer thermal insulation systems: - number of crews - 3; - number of working days per week - 6.
 The construction duration indicator is one of the most important at all stages of organizational, design and economic preparation for the installation of the house insulation system. The duration of warming is determined according to the calendar schedule. In turn, the cost of construction and installation work may change during the construction process due to changes in the cost of the project as a whole. Therefore, it is also quite relevant to determine the influence of organizational and technological factors on it.

Keunggulan Kompetitif Teknologi Modular Rumah Instan Sederhana Sehat (RISHA) Jayagiri

<p><em>The RISHA applied to the Jayagiri house was compared with conventional technology, in terms of construction duration, costs, and environmental friendliness. </em><em>T</em><em>he strength of the RISHA structure was be analyzed based on existing standards using SAP2000 and spColumn. The data were the literature studies and interviews with RISHA users, applicators, and the Directorate of Engineering Affairs for Human Settlements and Housing. Compared to conventional, the Jayagiri house is proven to be more eco-friendly with an efficiency value of 48.6 points. It was also built four weeks faster, with a lower cost of IDR123,043.90 per square meter, or 3.97%. </em><em>The</em><em> strength analysis shows that the capacity of the column reinforcement is still capable of carrying the designed loa</em><em>d</em><em>, the anchorage capacity of the X-direction beam has not met the requirements.</em></p>

Unauthorised Instructions in Civil Engineering Project: Contributing Factors

The civil engineering project, by its very nature, is a big user of natural resources. Nevertheless, with growing concerns on the climate change and the limit nature of these resources, there is increasing pressure to ensure the implementation of the construction to be completed within the stipulated quality, cost and time. This is due to the severity impacts on the environment it causes in the event that there is prolongation in the construction duration or face abandonment. Hence, this study looks upon the occurrence of unauthorised instructions as it is among the significant factor causing the project problems and delay. This paper aims to investigate the occurrence of unauthorised instruction in civil engineering projects and to determine the significant factors causing it. The data was obtained from professional civil engineers and Grade G7 contractors registered with their respective organisations i.e Board of Engineers Malaysia (BEM) and the Construction Industry Development Board (CIDB). From 288 questionnaire survey returns, this study determined that the occurrence of unauthorised instructions in civil engineering projects in Malaysia was at a moderate level. There were seven significant factors contributing to it namely poor in complying with the condition of contract, level of understanding condition of contract, ground uncertainty, the familiarity of procurement method used, tight project milestone, clarity of SFoC and project complexity. These seven factors if properly understood and be put more concern by all parties at the onset of every project may ensure the project can be successfully completed on time and eventually could reduce damage to the environment.

Robotic construction analysis: simulation with virtual reality

Advances in robotic construction are evident and increasing every year, bringing present and potential improvements. However, the economic and social impacts are hard to assess and quantify without physical in situ testing, which is expensive and time-consuming. This paper presents a methodology for the simulation of robotic construction technologies, namely drones, using a virtual reality environment. Our hypothesis is that a virtual reality simulation of a robotic construction (H1) has the potential of increasing the precision of predicting the construction duration and cost and (H2) allows for the detection of construction problems. The study begins with a review of the literature on drones, robotic arms, and hybrid automatic construction solutions, as well as virtual reality construction simulations, summarising the robotic technologies currently being used, mainly in academic research, to assemble construction elements. It then proposes a construction simulation methodology applied to three architectonic elements to analyse different approaches and different scenarios for robotic construction simulation methodology. A construction simulation is tested, and the data is analysed and compared with traditional construction methods, focussing on construction time and costs.

Developing six hybrid machine learning models based on gaussian process regression and meta-heuristic optimization algorithms for prediction of duration and cost of road tunnels construction

Tunnels are among essential subsurface projects used for various applications that often encounter instability, cost overruns and time consumption. Forecasting the duration and cost required to construct tunnels is always an essential factor in determining whether an assistant's decision-making system is useful or not. Therefore, research on the duration and cost of tunnels’ construction and the possibility of their distribution is essential, which can be a valid basis for concluding a contract and a tool to optimize the construction plan and reduce costs. In this work, six Gaussian process regression (GPR)-based meta-heuristic optimization algorithms, including GPR-PSO, GPR-GWO, GPR-MVO, GPR-MFO, GPR-SCA, and GPR-SSO were developed to predict the duration and cost parameters. 900 datasets, including 16 input parameters obtained through 34 historical road tunnels, were utilized in the models. The performance prediction of the developed models from high to low was GPR-PSO, GPR-GWO, GPR-MVO, GPR-MFO, GPR-SCA, GPR-SSO, and GPR, with ranking scores of 42, 36, 30, 22, 19, 13, and 6 (for the duration), and with ranking scores of 41, 35, 29, 23,19, 12, and 6 (for cost), respectively. However, the GPR-PSO hybrid model produced the most accurate results, and it was recommended to predict the duration and cost of road tunnels construction. The sensitivity analysis revealed that the most influential parameters on the duration and cost of tunnelling projects are the drilling machinery system and groundwater, respectively. The friction angle and cross-sectional tunnel were the least effective parameters for the duration and cost.

ANALISIS KELAYAKAN INVESTASI DALAM PENGAJUAN FASILITAS KREDIT PADA PT. XYZ

Abstract: PT. XYZ working in fertilizer trade to fulfill XYZ Group's fertilizer needs. The fertilizer supply is constrained by PT XYZ’s suppliers. In order to meet these fertilizer needs, PT. XYZ plans to build NPK plant located in Central Java. Investation is planned to use a bank credit facility. Based on the requirement in the credit application, an analysis of investment feasibility is carried out on the submission of PT. XYZ credit facilities. This research was conducted using a qualitative approach and a quantitative approach. A qualitative approach is used to examine non-financial aspects including review of the NPK fertilizer industry and business plan analysis. The quantitative approach is used to examine financial aspects including financial projections and sensitivity analysis. Review from NPK fertilizer industry, Indonesia have a market prospect of 4.8 million tons NPK fertilizer needs for palm oil plantation sector. The business plan for the construction of the NPK fertilizer plant includes a 300,000 MTPY capacity, chemical granulation based technology, fertilizer product with formulas 12-12-17 and 13-6-27, and Engineering, Procurement and Construction duration of project is 26 months. The results showed that the construction of NPK Fertilizer Plant was feasible in business and feasible to be financed with credit from creditors with an investment credit of Rp. 541,725,406,300 and working capital loans of Rp. 92,245,261,932, -. The feasibility of providing credit facilities is seen from the positive cash flow ability of NPK fertilizer sales and financial indicators, namely the Payback Period for 5.62 years, NPV (DF 11%) of Rp. 756,104,248,537, -, Internal Rate of Return 23.25%, Profitability Index 1.88.Keywords: NPK Fertilizer Industry, Business Plan Analysis, Financial Projection, Sensitivity Analysis, Payback Period, Internal Rate of Return, Net Present Value, Profitability Index

A Bayesian-driven Monte Carlo approach for managing construction schedule risks of infrastructures under uncertainty

The construction of infrastructures has often been challenged by construction delays, which are disruptive and expensive. As the construction of infrastructures is more complex and riskier under uncertainty, the construction schedule risks are becoming more interconnected and occurring in a chain of cascading events in practice. However, past research typically ignored the interdependency between sequence of risk occurrence (e.g., chronological and causal relationships). This research aims to close this gap through developing a novel approach based on Bayesian-driven Monte Carlo (BDMC) simulation for managing these interdependent construction schedule risks of infrastructures under uncertainty. This approach integrates hybrid data processing and analytics methods to (1) construct Bayesian network for identifying risks and risk interdependencies (i.e., causal relationships), (2) conduct risk inference and construction duration prediction involving both of chronological and causal relationships between risks, and (3) identify critical and sensitive risks and provide the most appropriate strategy for risk mitigation. The approach firstly pre-processes the data from risks and risk interdependencies to construct the risk network. It further constructs the Bayesian network using deep-first search (DFS), adapted maximum-weight spanning tree (A-MWST) algorithms and leaky-MAX model. Then the approach is developed for risk mapping based on BDMC simulation and for risk mitigation based on sensitivity and scenario analysis. Finally, a real infrastructure project is selected as the case study to verify this developed approach. Compared to conventional methods, the results show that the developed approach can provide more accurate schedule prediction with least 0.166% error ratio through incorporating interdependent risks into schedule prediction. It is also more informative through proposing effective risk mitigation strategies for delay avoidance and uncertainty reduction, and more convenient in data acquisition and processing when developing a Bayesian network through the developed hybrid data transformation approach converting the risk network into Bayesian network. This research contributes a new way to understand and analyse the interdependencies of risks and their impacts on construction schedule. The developed approach can be beneficial to managing construction schedule risks of infrastructures under uncertainty.

SELECTING HIGH PRIORITY ACTIVITIES FOR THE REALLOCATION OF RESOURCES TO REDUCE CONSTRUCTION DURATION

It is difficult to identify economically feasible alternatives to reduce the duration of construction, as many important factors are present in any given construction project, such as increased construction costs and incentives and decreased delay liquidated damages. Most importantly, thousands of activities are interconnected in a complicated manner. This study proposes a method for analyzing the priority of activities for the reallocation of resources in order to reduce construction delay duration. The proposed method is composed of two steps: the prioritization of activities that can reduce construction duration and a reallocation of resources based upon that prioritization. First, in order to analyze priority, combinations of the lowest-cost activities for reducing per day are derived. Then, the importance of influence factors is analyzed, using the fuzzy analytic hierarchy process and fuzzy inference, and priority is derived based on the importance level. Next, the resources are reallocated based on the objective functions of maximizing the importance of the selected activities, reducing the duration, and minimizing the reducing cost. Decision-makers can compare between the reduction duration and available cost, and compare between results of the proposed method and the existing cost-slope method. Then, decision-makers can use the proposed method differently based on their own preferences toward economic and qualitative importance.

Toward automated construction: The design-to-printing workflow for a robotic in-situ 3D printed house

In the construction industry, the labor shortage is a global issue. Characterized by the forming process of layered extrusion and rapid solidification, 3D concrete printing (3DCP) technology begins to be used in digital concrete construction to minimize the demand for manpower. However, the utilization of 3DCP in full-scale architectural constructions is still in its infancy, involving many manual processes like rebars-binding and formwork-making, which reduces the benefits of construction automation that should be brought by such technology. Therefore, this study proposes a design-to-printing workflow to 3D print the entire structure of a farmhouse in Wujiazhuang (WJZ) village. Firstly, design strategies are built up by a series of multi-disciplinary research, including printing system development, site planning, material design, and structure evaluation. Secondly, construction strategies involving printing process organization and man-hour-saving construction methods are utilized in the 3D printing process. By applying the introduced workflow, the project saves 62.4 % of human resources compared with the traditional reinforced concrete (RC) method, and the participation of 3D printing technologies arises from 18.3 % in the common 3DCP scenario to 76.5 % in this project. The on-site construction duration of the WJZ farmhouse is also reduced by 24.5 % in comparison with the unplanned construction process.

Insights into Increasing the Implementation of Concrete Overlay Rehabilitation Methods for Highway Pavements

Concrete overlays provide a promising solution to extending pavement life, and are currently the focus of the Federal Highway Administration Every Day Counts initiative. Despite their potential benefits, concrete overlays are not commonly used in many areas of the U.S.A., including the Southeast. A survey of 19 paving contractors active in the Southeastern U.S.A. was performed to quantify recent concrete overlay projects performed by these contractors, to assess the capabilities of contractors to construct concrete overlays in this region, and to identify barriers to implementation of concrete overlays as well as opportunities to increase their use. Findings indicated contractors in the region either had extensive overlay experience or no experience constructing concrete overlays. Regardless of the experience level of the contractor, the primary barrier to implementation is that this type of work is not being let for bid. Concerns about traffic control and safety was the second most important barrier among all contractors. Experienced contractors indicated the lack of available and skilled construction personnel were also key barriers. Inexperienced contractors cited concerns about the length and duration of construction as the third most important barrier. Respondents indicated an eagerness to bid on and complete overlays. The results of this study provide insight to regional state highway agencies, municipalities, and design engineers of the capabilities of concrete pavement contractors in the region to complete concrete overlay projects. The findings will help agencies understand the capabilities and concerns of concrete paving contractors and aid in informed decisions about overlays.

Impact of modularization and site staffing on construction schedule of small and large water reactors

Recent nuclear construction project schedules in the US and Europe were 2.5x their original estimates due to productivity misses, supply chain challenges, hiring constraints, and other issues. Small modular reactors are proposed as a remedy. Smaller reactors will require one fourth to one third the person-hours of labor and leverage more common supply chains, putting less strain on each step of the construction process. This study presents a methodology for estimating the construction duration of nuclear projects, so the sensitivity of proposed concepts to staffing and labor constraints can be analyzed. The methodology builds on a previous overnight capital cost estimation tool and builds a Gantt chart out of 226 tasks. The genetic algorithm assigns resources to each task to minimize construction time subject to peak staffing and hiring rate constraints. The results were consistently within 15% of seven benchmark durations. Under tighter labor constraints, the construction duration of large reactors increased 42% on average and only 3% for small reactors. Modularization of systems and structures reduced construction durations 60%, but it increased the sensitivity to labor constraints. Small reactors were more sensitive to the modularization assumptions because of the compact structures and layout, and the power specific cost ($/kW) sensitivity was higher, but the total financial impact was smaller because the total costs were lower.