The Impact of Fleet Size, Harvesting Site Reserve, and Timing of Machine Relocations on the Performance Indicators of Mechanized CTL Harvesting in Finland

Upscaling an operation typically results in economies of scale, i.e., cost advantages in business, especially when the production unit’s utilization rate can be improved. According to economic studies of mechanized timber harvesting, large wood harvesting entrepreneurs tend to be more successful in business than small entrepreneurs. What are the factors that influence harvesting costs, and how great is their effect on costs? These questions were investigated in mechanized cut-to-length timber harvesting in Eastern Finland by varying (a) the size of the harvesting fleet, (b) the harvesting site reserve, and (c) the timing and duration of the working day of machine relocations, in the case of an entrepreneur using a discrete-event simulation method. Prior to the simulations, harvesting site data were generated from the National Forest Inventory data by the MELA software, and the spatial data analyses by ArcGIS. According to the results, largely because of the low utilization rate of the contractor’s own relocation truck, the harvesting cost of a 2-harvesting-unit (2 HU) scenario was 9% or 6% higher than 4 HU, and 13% or 8% higher than 8 HU, with or without a specifically employed driver of a relocation truck, respectively (the harvesting unit consists of a harvester and a forwarder). In the 4 and 8 HU scenarios, harvesting costs decreased on average by 1% (0.3–1.5), when doubling the size of the harvesting site reserve. With fleet sizes of 6 and 8 HU, good utilization of a relocation truck reduced relocation costs, whereas machine costs only increased a small amount because of a longer machine relocation waiting time than with smaller entrepreneurs. The study raised the importance of entrepreneur-specific planning of machine relocations in the cost-efficient timber harvesting in Finland.

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Nachhaltiges Holzproduktionspotenzial im Schweizer Wald

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2011.0300 ◽

2011 ◽

Vol 162 (9) ◽

pp. 300-311 ◽

Cited By ~ 7

Author(s):

Edgar Kaufmann

Keyword(s):

Forest Management ◽

Management Strategies ◽

National Forest Inventory ◽

Forest Area ◽

Long Term Effects ◽

Growing Stock ◽

Rotation Periods ◽

The Impact ◽

Harvesting Costs

Potential of sustainable wood production in Swiss forests In the Swiss National Forest Inventory (NFI), the data collected in the three inventories (NFI1 1983–1985, NFI2 1993–1995, NFI3 2004–2006) provide the basis not only for analysing the present state of the forest and how it has developed up to now, but also for assessing, with the help of models, how it might develop in future. The scenario model «Massimo 3», developed at the Swiss Federal Institut for Forest, Snow and Landscape Research, is an empirical and stochastic simulation model. It relies on data from the NFI and forecasts the development of the forest according to how it is managed. Six scenarios with different management regimes were defined according to the economic, silvicultural and ecological aspects considered. In three scenarios the growing stock is kept constant at the level of NFI3, but different management strategies are used (Scenario A: basis [business as usual], Scenario E: even-aged forests are transformed into uneven-aged forests, and Scenario F: near-natural percentages of conifers are promoted). In two scenarios forest management is partially abandoned for either ecological reasons (Scenario B: reservations, 10% of the forest area is left unmanaged) or for economic reasons (Scenario C: harvesting costs, 40% of the forest area is left unmanaged). Scenario D (rotation periods are shortened) was used to study the effects of augmenting the annual harvesting amount. A forecasting time period of 100 years was selected to assess the long-term effects of the scenarios. Scenarios A, D, and E show that the sustainable harvesting potential of merchantable wood lies in a relatively narrow range of 7.1 to 7.3 million m3/year, even though in Scenario D the growing stock is reduced from 360 m3/ha to 305 m3/ha. In Scenario F regeneration is systematically established with near-natural percentages of conifers, the long-term harvesting potential is slightly less: about 6.5 million m3/year of merchantable wood. If forest management is abandoned for economic reasons on as much as 40% of the forest area (Scenario C, harvesting costs), the impact on the wood reserves is very negative.

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Data-Driven Design Strategies to Address Crowding and Boarding in an Emergency Department: A Discrete-Event Simulation Study

HERD Health Environments Research & Design Journal ◽

10.1177/1937586720969933 ◽

2020 ◽

pp. 193758672096993

Author(s):

Shabboo Valipoor ◽

Mohsen Hatami ◽

Hesamedin Hakimjavadi ◽

Elif Akçalı ◽

Wendy A. Swan ◽

...

Keyword(s):

Discrete Event Simulation ◽

Discrete Event ◽

Data Driven ◽

Utilization Rate ◽

Design Strategies ◽

Event Simulation ◽

Lengths Of Stay ◽

Exam Room ◽

The Impact ◽

Room Time

Objective: To address prolonged lengths of stay (LOS) in a Level 1 trauma center, we examined the impact of implementing two data-driven strategies with a focus on the physical environment. Background: Crowding in emergency departments (EDs) is a widely reported problem leading to increased service times and patients leaving without being seen. Methods: Using ED historical data and expert estimates, we created a discrete-event simulation model. We analyzed the likely impact of initiating care and boarding patients in the hallway (hallway care) instead of the exam rooms and adding a dedicated triage space for patients who arrive by emergency medical services (EMS triage) to decrease hallway congestion. The scenarios were compared in terms of LOS, time spent in exam rooms and hallway spaces, service time, blocked time, and utilization rate. Results: The hallway care scenario resulted in significantly lower LOS and exam room time only for EMS patients but when implemented along with the EMS triage scenario, a significantly lower LOS and exam room time was observed for all patients (EMS and walk-in). The combination of two simulated scenarios resulted in significant improvements in other flow metrics as well. Conclusions: Our findings discourage boarding of admitted patients in ED exam rooms. If space limitations require that admitted patients be placed in ED hallways, designers and planners should consider enabling hallway spaces with features recommended in this article. Alternative locations for boarding should be prioritized in or out of the ED. Our findings also encourage establishing a triage area dedicated to EMS patients in the ED.

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Ansätze zur Senkung der Holzerntekosten in der Schweiz

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2013.0148 ◽

2013 ◽

Vol 164 (6) ◽

pp. 148-157 ◽

Cited By ~ 2

Author(s):

Patric Bürgi ◽

Bernhard Pauli

Keyword(s):

Economies Of Scale ◽

Timber Harvest ◽

Timber Harvesting ◽

Enterprise Management ◽

Cause And Effect ◽

Timber Sales ◽

Large Numbers ◽

Forest Enterprises ◽

Operation Results ◽

Harvesting Costs

Approaches to reducing timber harvesting costs in Switzerland For over two decades, the majority of Swiss forest enterprises have been confronted with financial losses. One of the main reasons for this is the general diminishing of revenues from timber sales since the 1980s. Moreover, Swiss forest enterprises have not managed to reduce the most important matter of expenses – the timber harvesting costs – to a similar extent. In comparison, unit costs from timber harvest in Switzerland are more than twice as high as those in the neighboring countries. This study analyzes the cause-and-effect relationships that lead to the high timber harvesting costs in Swiss forest enterprises. Building on that, possibilities of reducing these costs are proposed. The study is based on the results obtained through the Swiss Forestry Holding Network (HDN). The results have been systematically analyzed, the cause-and-effect relationships graphically depicted, and the gained knowledge has been discussed with experts. In essence, the results from the HDN suggest that the high timber harvesting costs are primarily a consequence of the structural situation of the Swiss forest enterprises. The over-proportionally high number of employees and large machinery parks allocated to each of the management areas are inevitably leading to high timber harvesting costs, and thus to suboptimal timber harvesting methods. Subsequently, this is all giving rise to an unfavorable cost situation. Furthermore, economies of scale can hardly be reached among the large numbers of relatively small forest enterprise management areas producing low usage quantities. In essence, the most important approaches to reducing the timber harvesting costs are the more frequent involvement of specialized forest services for harvesting, and measures that lead to the enlargement of the management areas. In order to reduce timber harvesting costs and by that improve operation results, a critical reflection of the current forest management strategy is unavoidable.

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The Impact of a Chemostat Discharge Containing Oil Degrading Bacteria on the Biological Kinetics of a Refinery Activated Sludge Process

Water Science & Technology ◽

10.2166/wst.1988.0276 ◽

1988 ◽

Vol 20 (11-12) ◽

pp. 131-136 ◽

Cited By ~ 7

Author(s):

A. D. Wong ◽

C. D. Goldsmith

Keyword(s):

Activated Sludge ◽

Retention Time ◽

Waste Treatment ◽

Treatment Plant ◽

Utilization Rate ◽

Activated Sludge Process ◽

Kinetic Evaluation ◽

Degrading Bacteria ◽

Waste Treatment Plant ◽

The Impact

The effect of discharging specific oil degrading bacteria from a chemostat to a refinery activated sludge process was determined biokinetically. Plant data for the kinetic evaluation of the waste treatment plant was collected before and during treatment. During treatment, the 500 gallon chemostatic growth chamber was operated on an eight hour hydraulic retention time, at a neutral pH, and was fed a mixture of refinery wastewater and simple sugars. The biokinetic constants k (days−1), Ks (mg/L), and K (L/mg-day) were determined before and after treatment by Monod and Lineweaver-Burk plots. Solids discharged and effluent organic concentrations were also evaluated against the mean cell retention time (MCRT). The maximum utilization rate, k, was found to increase from 0.47 to 0.95 days−1 during the operation of the chemostat. Subsequently, Ks increased from 141 to 556 mg/L. Effluent solids were shown to increase slightly with treatment. However, this was acceptable due to the polishing pond and the benefit of increased ability to accept shock loads of oily wastewater. The reason for the increased suspended solids in the effluent was most likely due to the continual addition of bacteria in exponential growth that were capable of responding to excess substrate. The effect of the chemostatic addition of specific microbial inocula to the refinery waste treatment plant has been to improve the overall organic removal capacity along with subsequent gains in plant stability.

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Effects of Regional Bank Merger on Small Business Borrowing: Evidence from Japan

International Journal of Economics and Finance ◽

10.5539/ijef.v7n11p62 ◽

2015 ◽

Vol 7 (11) ◽

pp. 62

Author(s):

Hironobu Miyazaki ◽

Hiroyuki Aman

Keyword(s):

Small Business ◽

Small Businesses ◽

Economies Of Scale ◽

Loan Portfolio ◽

Small Business Lending ◽

Borrowing Costs ◽

Bank Merger ◽

Regional Bank ◽

Small Business Loans ◽

The Impact

This study examines the impact of a regional bank merger in Japan on borrowing by small businesses, focusing on firms that borrow from the acquiring bank, the acquired bank, or both. First, we find that post-merger borrowing costs declined. This result suggests that small borrowers enjoy more favorable post-merger financing conditions because efficiencies from economies of scale lead to lower costs. Second, we<strong> </strong>find that post-merger borrowing costs decline for firms that borrow only from the acquiring or acquired bank, whereas they did not decline for firms that borrow from both. Third, we find that only small business loans to firms that borrow from both the acquiring and acquired banks decrease post-merger. This result suggests that small business lending might decline because of a merged bank’s loan portfolio and lending strategy.

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Stochastic simulation for determining the design flood of cascade reservoir systems

Hydrology Research ◽

10.2166/nh.2011.002 ◽

2012 ◽

Vol 43 (1-2) ◽

pp. 54-63 ◽

Cited By ~ 6

Author(s):

Baohong Lu ◽

Huanghe Gu ◽

Ziyin Xie ◽

Jiufu Liu ◽

Lejun Ma ◽

...

Keyword(s):

Simulation Model ◽

Stochastic Simulation ◽

Southern China ◽

Flow Simulation ◽

Simulation Method ◽

Simulation Approach ◽

Design Flood ◽

Design Values ◽

Stochastic Simulation Model ◽

The Impact

Stochastic simulation is widely applied for estimating the design flood of various hydrosystems. The design flood at a reservoir site should consider the impact of upstream reservoirs, along with any development of hydropower. This paper investigates and applies a stochastic simulation approach for determining the design flood of a complex cascade of reservoirs in the Longtan watershed, southern China. The magnitude of the design flood when the impact of the upstream reservoirs is considered is less than that without considering them. In particular, the stochastic simulation model takes into account both systematic and historical flood records. As the reliability of the frequency analysis increases with more representative samples, it is desirable to incorporate historical flood records, if available, into the stochastic simulation model. This study shows that the design values from the stochastic simulation method with historical flood records are higher than those without historical flood records. The paper demonstrates the advantages of adopting a stochastic flow simulation approach to address design-flood-related issues for a complex cascade reservoir system.

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Erosion Transportation Processes as Influenced by Gully Land Consolidation Projects in Highly Managed Small Watersheds in the Loess Hilly–Gully Region, China

Water ◽

10.3390/w13111540 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1540

Author(s):

Qianqian Ji ◽

Zhe Gao ◽

Xingyao Li ◽

Jian’en Gao ◽

Gen’guang Zhang ◽

...

Keyword(s):

Similarity Theory ◽

Design Method ◽

Simulation Method ◽

Practical Significance ◽

Land Consolidation ◽

Small Watershed ◽

Flood Peak ◽

Erosion Area ◽

The Impact ◽

Erosion Environment

The Loess Hilly–Gully region (LHGR) is the most serious soil erosion area in the world. For the small watershed with high management in this area, the scientific problem that has been paid attention to in recent years is the impact of the land consolidation project on the erosion environment in the gully region. In this study, the 3D simulation method of vegetation, eroded sediment and pollutant transport was innovated based on the principles of erosion sediment dynamics and similarity theory, and the impacts of GLCP were analyzed on the erosion environment at different scales. The verification results show that the design method and the scale conversion relationship (geometric scale: λl = 100) were reasonable and could simulate the transport process on the complex underlying surface of a small watershed. Compared with untreated watersheds, a significant change was the current flood peak lagging behind the sediment peak. There were two important critical values of GLCP impact on the erosion environment. The erosion transport in HMSW had no change when the proportion was less than 0.85%, and increased obviously when it was greater than 3.3%. The above results have important theoretical and practical significance for watershed simulation and land-use management in HMSW.

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Sustainability of Extraction of Raw Material by a Combination of Mobile and Stationary Mining Machines and Optimization of Machine Life Cycle

Sustainability ◽

10.3390/su122410454 ◽

2020 ◽

Vol 12 (24) ◽

pp. 10454

Author(s):

Katarína Teplická ◽

Martin Straka

Keyword(s):

Life Cycle ◽

Raw Materials ◽

Simulation Method ◽

Raw Material ◽

Optimal Distribution ◽

Transport Costs ◽

Scientific Discussion ◽

Mining Companies ◽

Conveyor Belts ◽

The Impact

This article summarizes the arguments within the scientific discussion on the issue of using mining machines and their life cycle. The main goal of the article is to investigate the impact of a combination of mobile and stationary mining machines and their optimal distribution in the mining process to increase the efficiency of mining and processing of raw materials. The following methods of research were focused on the use of technical indicators for the valuation efficiency of the mining process: a simulation method was used for the distribution of mining machines, comparison analysis was used for the real and past state of mining machines, and a decision tree was used as managerial instrument for optimal alternatives of mining machines. The research empirically confirms and theoretically proves that optimal distribution of mining machines and machine parks is very important for mining companies. The benefit of this research for the mining company was the new location of the machines and the combination of stationary production lines and mobile equipment. The optimal layout of the machines reduced the number of conveyor belts and improved the transfer of limestone processing to mobile devices, saving time, which was reflected in transport costs. The results can be useful for other mining companies seeking to create an optimal machine park.

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Spatial Agglomeration of China’s Forest Products Manufacturing Industry: Measurement, Characteristics and Determinants

Forests ◽

10.3390/f12081006 ◽

2021 ◽

Vol 12 (8) ◽

pp. 1006

Author(s):

Zhenhuan Chen ◽

Hongge Zhu ◽

Wencheng Zhao ◽

Menghan Zhao ◽

Yutong Zhang

Keyword(s):

Spatial Distribution ◽

Spatial Data ◽

Large Scale ◽

Manufacturing Industry ◽

Economies Of Scale ◽

Forest Products ◽

Spatial Data Analysis ◽

Forest Protection ◽

Spatial Agglomeration ◽

Continuous Space

China’s forest products manufacturing industry is experiencing the dual pressure of forest protection policies and wood scarcity and, therefore, it is of great significance to reveal the spatial agglomeration characteristics and evolution drivers of this industry to enhance its sustainable development. Based on the perspective of large-scale agglomeration in a continuous space, in this study, we used the spatial Gini coefficient and standard deviation ellipse method to investigate the spatial agglomeration degree and location distribution characteristics of China’s forest products manufacturing industry, and we used exploratory spatial data analysis to investigate its spatial agglomeration pattern. The results show that: (1) From 1988 to 2018, the degree of spatial agglomeration of China’s forest products manufacturing industry was relatively low, and the industry was characterized by a very pronounced imbalance in its spatial distribution. (2) The industry has a very clear core–periphery structure, the spatial distribution exhibits a “northeast-southwest” pattern, and the barycenter of the industrial distribution has tended to move south. (3) The industry mainly has a high–high and low–low spatial agglomeration pattern. The provinces with high–high agglomeration are few and concentrated in the southeast coastal area. (4) The spatial agglomeration and evolution characteristics of China’s forest products manufacturing industry may be simultaneously affected by forest protection policies, sources of raw materials, international trade and the degree of marketization. In the future, China’s forest products manufacturing industry should further increase the level of spatial agglomeration to fully realize the economies of scale.

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Balancing scarce hospital resources during the COVID-19 pandemic using discrete-event simulation

Health Care Management Science ◽

10.1007/s10729-021-09548-2 ◽

2021 ◽

Author(s):

G.J. Melman ◽

A.K. Parlikad ◽

E.A.B. Cameron

Keyword(s):

Resource Allocation ◽

Discrete Event Simulation ◽

Elective Surgery ◽

Discrete Event ◽

Specific Patient ◽

Event Simulation ◽

The Impact ◽

Allocation Decisions ◽

Allocation Strategies ◽

Resource Allocation Decisions

AbstractCOVID-19 has disrupted healthcare operations and resulted in large-scale cancellations of elective surgery. Hospitals throughout the world made life-altering resource allocation decisions and prioritised the care of COVID-19 patients. Without effective models to evaluate resource allocation strategies encompassing COVID-19 and non-COVID-19 care, hospitals face the risk of making sub-optimal local resource allocation decisions. A discrete-event-simulation model is proposed in this paper to describe COVID-19, elective surgery, and emergency surgery patient flows. COVID-19-specific patient flows and a surgical patient flow network were constructed based on data of 475 COVID-19 patients and 28,831 non-COVID-19 patients in Addenbrooke’s hospital in the UK. The model enabled the evaluation of three resource allocation strategies, for two COVID-19 wave scenarios: proactive cancellation of elective surgery, reactive cancellation of elective surgery, and ring-fencing operating theatre capacity. The results suggest that a ring-fencing strategy outperforms the other strategies, regardless of the COVID-19 scenario, in terms of total direct deaths and the number of surgeries performed. However, this does come at the cost of 50% more critical care rejections. In terms of aggregate hospital performance, a reactive cancellation strategy prioritising COVID-19 is no longer favourable if more than 7.3% of elective surgeries can be considered life-saving. Additionally, the model demonstrates the impact of timely hospital preparation and staff availability, on the ability to treat patients during a pandemic. The model can aid hospitals worldwide during pandemics and disasters, to evaluate their resource allocation strategies and identify the effect of redefining the prioritisation of patients.

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