Proportional Costs Research Articles

An interrater reliability study of gait analysis systems with the dual task paradigm in healthy young and older adults

Background and aimsOne reason for the controversial discussion of whether the dual task (DT) walking paradigm has an added value for diagnosis in clinical conditions might be the use of different gait measurement systems. Therefore, the purpose was 1) to detect DT effects of central gait parameters obtained from five different gait analysis devices in young and old adults, 2) to assess the consistency of the measurement systems, and 3) to determine if the absolut and proportional DT costs (DTC) are greater than the system-measurement error under ST.MethodsTwelve old (72.2 ± 7.9y) and 14 young adults (28.3 ± 6.2y) walked a 14.7-m distance under ST and DT at a self-selected gait velocity. Interrater reliability, precision of the measurement and sensitivity to change were calculated under ST and DT.ResultsAn age effect was observed in almost all gait parameters for the ST condition. For DT only differences for stride length (p < .029, ɳ2p = .239) as well as single and double limb support (p = .036, ɳ2p = .227; p = .034, ɳ2p = .218) remained. The measurement systems showed a lower absolute agreement compared to consistency across all systems.ConclusionsWhen reporting DT effects, the real changes in performance and random measurement errors should always be accounted for. These findings have strong implications for interpreting DT effects.

Carcass Traits, Organ Proportion and Bio-Economic Cost Benefits Analysis of Broiler Chickens Fed Different Dietary Plant Protein Sources in Sorghum-Based Diet

A 56-day study was carried out to evaluate the carcass characteristics and organ proportions of broiler chickens fed sorghum-based diets with varying plant protein. A total of 120 day-old broiler chickens from a reputable and disease free farm were used for this study. There were four treatments, each having thirty broiler birds replicated thrice with ten broiler birds per replicate using a Completely Randomized Design (CRD). The broiler birds were offered feed and water ad libitum. The growth parameters were taken on weekly basis. Carcass evaluation was carried out at the end of the trial. One bird per replicate was randomly selected, fasted over-night and slaughtered by severing the jugular vein. After scalding in warm water for about a minute, the feathers were manually plucked, each bird was cut into parts for carcass evaluation. The relative weights of the cut parts were as a percentage of dressed weight. The internal organs, such as heart, kidney, gizzard/proventriculus were all weighed separately and recorded using electric micrometer (3000g weighing gauge). The findings from this study showed that all the carcass parameters considered showed significant differences (p&lt;0.05). Birds fed diet 3 gave the best live weight, slaughtered weight, defeathered weight, dressed weight and commensurate cut-parts. Soybean (whether cake or full-fat) demonstrate superiority over groundnut cake and cashew nut cake. Birds fed diet 3 gave the highest value of thigh, breast -cut, drumstick and wings, while birds fed diets 2, 1 and 4 gave less. The organ proportions of broiler chickens fed different dietary plant sources have all the parameters significantly difference (p&lt;0.05), except the lungs though without any definite pattern. Average weight gain and feed conversion ratio were better (p&lt;0.05) among birds fed diet 2, and 3. Cost benefits analysis per kilogram in naira terms for birds fed different plant protein sources in a sorghum-based diets were significant (p&lt;0.05) among treatment levels. Least cost per kg feed was obtained in diet 1 (p&lt;0.05). Cost of weight gained was (p&lt;0.05) low in T1. Cost of feed consumed was low for diet T1 and T3. Revenue, gross margin and cost benefit ratio estimated were found to high (p&lt;0.05) among T2 and T3. Broiler chickens fed diet 3 gave the best parameters. The actual contributions of the experiment, is to alternatively replace corn with sorghum completely at least cost with optimum performance.

Trade credit or vertical merger strategy for financial constrained retailer in a supply chain with asymmetric competing retailers

Motivated by the practices that many small and middle-sized enterprises (SME) retailers have financial constraints due to their limited budget and financing access, this paper studies the manufacturer’s financial strategy (i.e., trade credit versus vertical merger with a capital-constrained retailer) in a supply chain with two financial asymmetric retailers. We first compare the equilibrium profits under different financing modes and find that if manufacturer’s capital cost under trade credit or administrative cost under vertical merger is below a certain threshold, the manufacturer should finance instead of deselect the capital-constrained retailer even though the competition is intensified. Furthermore, manufacturer can choose a financing strategy based on the tradeoff between financing value and cost from trade credit or vertical merger. Under trade credit, the increased horizontal competition intensity is against the capital-constrained retailer while with vertical merger the competition intensity is harmful to the capital-abundant retailer. In addition, through investigating the impact of different financial modes on the equilibrium profits of the supply chain players, we find that whether trade credit can outperform vertical merger for both the manufacturer and the capital-constrained retailer depends on horizontal competition intensity, profit-sharing proportion and administrative cost of vertical merger. Moreover, the capital-abundant retailer will get the lowest profit when other participators act like an alliance. Our study provides a roadmap for the manufacturer to make a financing policy for capital-constrained retailer who competes with a funded retailer.

Singular Control of the Drift of a Brownian System

We consider a standard Brownian motion whose drift can be increased or decreased in a possibly singular manner. The objective is to minimize an expected functional involving the time-integral of a running cost and the proportional costs of adjusting the drift. The resulting two-dimensional degenerate singular stochastic control problem has interconnected dynamics and it is solved by combining techniques of viscosity theory and free boundary problems. We provide a detailed description of the problem’s value function and of the geometry of the state space, which is split into three regions by two monotone curves. Our main result shows that those curves are continuously differentiable with locally Lipschitz derivative and solve a system of nonlinear ordinary differential equations.

Emissions trading with transaction costs

We develop an equilibrium model of emissions permit trading in the presence of fixed and proportional trading costs in which the permit price and firms' participation in and extent of trading are endogenously determined. We analyze the sensitivity of the equilibrium to changes in the trading costs and firms' allocations, and characterize situations where the trading costs depress or raise permit prices relative to frictionless market conditions. We calibrate our model to annual transaction data in Phase II of the EU ETS (2008–2012) and find that trading costs in the order of 10 k€ per annum plus 1 € per permit traded substantially reduce discrepancies between observations and theoretical predictions for firms’ behavior (e.g. autarkic compliance for small and/or long firms). Our simulations suggest that ignoring trading costs leads to an underestimation of the price impacts of supply-curbing policies, this difference varying with the incidence on firms.

Equity Cost Induced Dichotomy for Optimal Dividends with Capital Injections in the Cramér-Lundberg Model

We investigate a control problem leading to the optimal payment of dividends in a Cramér-Lundberg-type insurance model in which capital injections incur proportional cost, and may be used or not, the latter resulting in bankruptcy. For general claims, we provide verification results, using the absolute continuity of super-solutions of a convenient Hamilton-Jacobi variational inequality. As a by-product, for exponential claims, we prove the optimality of bounded buffer capital injections (−a,0,b) policies. These policies consist in stopping at the first time when the size of the overshoot below 0 exceeds a certain limit a, and only pay dividends when the reserve reaches an upper barrier b. An exhaustive and explicit characterization of optimal couples buffer/barrier is given via comprehensive structure equations. The optimal buffer is shown never to be of de Finetti (a=0) or Shreve-Lehoczy-Gaver (a=∞) type. The study results in a dichotomy between cheap and expensive equity, based on the cost-of-borrowing parameter, thus providing a non-trivial generalization of the Lokka-Zervos phase-transition Løkka-Zervos (2008). In the first case, companies start paying dividends at the barrier b*=0, while in the second they must wait for reserves to build up to some (fully determined) b*&gt;0 before paying dividends.

Full-waveform inversion strategies using common-receiver gathers for ocean-bottom cable data

Full-waveform inversion (FWI), which is among the most powerful seismic data processing techniques for imaging subsurface geological structures, has a huge computational cost in proportion to the number of sources. To increase the speed of FWI, we explored the use of common-receiver gathers (CRGs) as an alternative to common-shot gathers (CSGs) as observed data. This approach has the potential to reduce the computational cost of FWI significantly, particularly for ocean-bottom cable (OBC) acquisition. As we match modelled and observed CSGs in CSG-based FWI, we match observed CRGs with modelled CSGs of switched source–receiver geometry in CRG-based FWI. According to the reciprocity principle, CRG FWI based on the steepest descent or Gauss–Newton method yields the same inverted velocity models as CSG FWI for an identical and known source signature applied over whole source positions. However, when the source wavelet is unknown, and changes from one source position to another, each trace of a CRG contains a different source signature, making it difficult to apply conventional source estimation or source-independent methods to CRG FWI. Therefore, in this study, we proposed inversion strategies for CRG FWI in both the time and frequency domains to deal with errors arising from different source wavelets between CRG traces. Then, we used a synthetic example for the Marmousi-II model and a real data example from the North Sea to demonstrate that our strategies for CRG FWI provide very similar inverted velocity models to those obtained from CSG FWI, at a lower computational cost.

Online monitoring of structural materials integrity in process industry for I4.0: A focus on material loss through erosion and corrosion sensing

This paper presents a critical review of the main sensing techniques considered for online monitoring of the integrity of alloys steel-made equipment used in process industry. This includes pipelines, tanks, electrical transformers and other metallic structures used in construction of buildings and bridges. Radio frequency (RF), Magnetic flux leak (MFL), ultrasonic-acoustic, fiber brag grating (FBG), thin layer strips, and photoacoustic sensors remain the main sensing techniques used or suggested for this purpose. However, despite lot of research works to improve their sensitivity and accuracy, further efforts are required to have them readily operational in the field especially for covering large volumes. This can be facilitated by the significant development carried out in various areas related to information technology (IT) and instrumentation, such as optical fiber sensors and self-powered wireless sensors under I4.0 paradigm. While optical fiber sensors, particularly FBG sensors, have the advantage to be scalable to cover wide areas with a few number of wires, they encounter the challenge of being not highly sensitive, especially for detecting degradations e.g. corrosion and erosion occurring at the opposite side of the steel structure. In addition, for such types of degradations, the fiber needs to be permanently and tightly connected to the structure, which is difficult to sustain. In addition, their proportional cost to the target sensitivity and resolution remains expensive. Wireless sensors equipped with ultrasonic sensors remain another tangible potential alternative for detecting internal corrosion and erosion of the structures if some pending issues relevant to power supply, using for instance energy harvesting, are sorted out. Overall, the existing technologies still suffer from a lack of sensitivity, accuracy, universality and/or cost effectiveness which justifies that more development efforts need to be done.

Forecasting and trading cryptocurrencies with machine learning under changing market conditions

This study examines the predictability of three major cryptocurrencies—bitcoin, ethereum, and litecoin—and the profitability of trading strategies devised upon machine learning techniques (e.g., linear models, random forests, and support vector machines). The models are validated in a period characterized by unprecedented turmoil and tested in a period of bear markets, allowing the assessment of whether the predictions are good even when the market direction changes between the validation and test periods. The classification and regression methods use attributes from trading and network activity for the period from August 15, 2015 to March 03, 2019, with the test sample beginning on April 13, 2018. For the test period, five out of 18 individual models have success rates of less than 50%. The trading strategies are built on model assembling. The ensemble assuming that five models produce identical signals (Ensemble 5) achieves the best performance for ethereum and litecoin, with annualized Sharpe ratios of 80.17% and 91.35% and annualized returns (after proportional round-trip trading costs of 0.5%) of 9.62% and 5.73%, respectively. These positive results support the claim that machine learning provides robust techniques for exploring the predictability of cryptocurrencies and for devising profitable trading strategies in these markets, even under adverse market conditions.

Scientific approach to quantitative measurement and economic processes research in corporate management

Theoretical and methodological studies of quantitative measurement problems of the outcome economic indicators in corporate management are examined in the article. The author’s vision of scientific exploration as one of the corporate management optimization directions is offered and the basis of such direction as profit margin calculation methodology is presented. It is also suggested to solve problems of quantitative measurement of basic economic processes by using allocation of fixed costs in proportion to profit margin. The methodological basis for evaluating cost-effectiveness with the help of profit margin ratio is developed by the authors. It was revealed that fixed costs are the conditions for doing business and the functional purpose of profit margin is the fixed costs coverage. It is proved that in case of multi-assortment production one of the most effective corporate management approaches to cost estimation and pricing is the profit margin concept provided in this article. One of the advantages of proposed profit margin concept is the availability of special tools revealing the resources that allow covering fixed costs and generating profit with a given level of cost-effectiveness. The obtained results of further adoption can be applied as element of corporate management of manufacturing companies and enterprises in conditions of multi-assortment production and changeable economic environment

Aggregation-Based Colocation Datacenter Energy Management in Wholesale Markets

In this paper, we study how colocation datacenter energy cost can be effectively reduced in the wholesale electricity market via cooperative power procurement. Intuitively, by aggregating workloads and renewables across a group of tenants in a colocation datacenter, the overall power demand uncertainty of the colocation datacenter can be reduced, resulting in less chance of being penalized when participating in the wholesale electricity market. We use cooperative game theory to model the cooperative electricity procurement process of tenants as a cooperative game, and show the cost saving benefits of aggregation. Then, a cost allocation scheme based on the marginal contribution of each tenant to the total expected cost is proposed to distribute the aggregation benefits among the participating tenants. Besides, we propose proportional cost allocation scheme to distribute the aggregation benefits among the participating tenants after realizations of power demand and market prices. Finally, numerical experiments based on real-world traces are conducted to illustrate the benefits of aggregation compared to noncooperative power procurement.

Capital Intensity and Labour Productivity in Waste Companies

At first glance, it might seem that the economic aspects of sustainability in terms of waste management have resolved themselves already in areas of activity. In reality, however, companies in this area also need to address how to ensure their future operations. The primary priority for companies in the area of waste disposal is to provide efficient collection, sorting, and recycling, effectively using company resources. The goal of this paper was to explore the relation between capital intensity and the productivity of labour in companies in the waste sector in the countries of the Visegrad Group (V4), and consequently, to define the bonds among economic indicators in the form of the economic normal. The study used data from 875 enterprises from the V4 countries, which were divided into categories according to the development of capital intensity and labour productivity. This study found that companies mainly implement modest investment development, which was characterised by the high effectiveness of capital usage, diminishing labour productivity, low labour endowment, but at the same time, increasing profitability. The reason for the labour productivity decrease was due to the growing proportional cost of labour. This trend was typical for most of the large-sized and middle-sized companies, whereas for most small companies, there was a dominant severe capital development with decreasing labour productivity and relatively high profitability of incomes. The smallest representation takes companies with capital-intensive development with the positive development of all monitored economic indicators.

The role of proportionality in the law of transboundary waters

Equitable and reasonable utilization, the core substantive rule of the law of transboundary waters, requires the utilization of transboundary waters by States, considering the needs and interests of other States. This implies that the uses and benefits of transboundary waters should be shared in proportion to each basin State’s needs. Such needs are calculated through the consideration and balancing of factors associated with the rule of equitable and reasonable utilization. However, the formulation of the rule in the 1997 Convention on the Law of the Non‐navigational Uses of International Watercourses does not prescribe how the balancing between competing needs of the transboundary watercourse States may be achieved. This article argues that the principle of proportionality can play a role in facilitating the equitable balancing between the competing needs of States in transboundary river basins. Proportionality can also play a role in informing the balancing inherent in other substantive and procedural rules and dispute resolution in the law of transboundary waters. The article further examines the role of proportionality in benefit‐sharing practices in transboundary river basins, where States have adopted a proportionate cost–benefit‐sharing approach. The article uses China as an example to understand the role of proportionality in informing Chinese transboundary water treaties.

Patient-Reported Outcomes of Robotic vs Laparoscopic Ventral Hernia Repair With Intraperitoneal Mesh

Despite rapid adoption of the robotic platform for ventral hernia repair with intraperitoneal mesh in the United States, there is no level I evidence comparing it with the traditional laparoscopic approach. This randomized clinical trial sought to demonstrate a clinical benefit to the robotic approach.To determine whether robotic approach to ventral hernia repair with intraperitoneal mesh would result in less postoperative pain.A registry-based, single-blinded, prospective randomized clinical trial at the Cleveland Clinic Center for Abdominal Core Health, Cleveland, Ohio, completed between September 2017 and January 2020, with a minimum follow-up duration of 30 days. Two surgeons at 1 academic tertiary care hospital. Patients with primary or incisional midline ventral hernias of an anticipated width of 7 cm or less presenting in the elective setting and able to tolerate a minimally invasive repair.Patients were randomized to a standardized laparoscopic or robotic ventral hernia repair with fascial closure and intraperitoneal mesh.The trial was powered to detect a 30% difference in the Numerical Rating Scale (NRS-11) on the first postoperative day. Secondary end points included the Patient-Reported Outcomes Measurement Information System Pain Intensity short form (3a), hernia-specific quality of life, operative time, wound morbidity, recurrence, length of stay, and cost.Seventy-five patients completed their minimally invasive hernia repair: 36 laparoscopic and 39 robotic. Baseline demographics and hernia characteristics were comparable. Robotic operations had a longer median operative time (146 vs 94 minutes; P < .001). There were 2 visceral injuries in each cohort but no full-thickness enterotomies or unplanned reoperations. There were no significant differences in NRS-11 scores preoperatively or on postoperative days 0, 1, 7, or 30. Specifically, median NRS-11 scores on the first postoperative day were the same (5 vs 5; P = .61). Likewise, postoperative Patient-Reported Outcomes Measurement Information System 3a and hernia-specific quality-of-life scores, as well as length of stay and complication rates, were similar. The robotic platform adds cost (total cost ratio, 1.13 vs 0.97; P = .03), driven by the cost of additional operating room time (1.25 vs 0.85; P < .001).Laparoscopic and robotic ventral hernia repair with intraperitoneal mesh have comparable outcomes. The increased operative time and proportional cost of the robotic approach are not offset by a measurable clinical benefit.ClinicalTrials.gov Identifier: NCT03283982.

Two-Step Continuous-Control Set Model Predictive Current Control Strategy for SPMSM Sensorless Drives

Integration of model predictive current control (MPCC) and the existing position estimation method is an attractive and promising strategy for surface-mounted permanent magnet synchronous machines (SPMSMs) sensorless drives. However, its system control performance is severely weakened by the filter delay and position estimation errors in the position estimation process because the conventional MPCC requires accurate rotor position information. In order to effectively resolve these problems, a two-step continuous-control-set MPCC (TS-CCS-MPCC) strategy is proposed in this paper. By adopting the two-step prediction to complete the machine mathematical model, the predictive currents can be obtained without the estimated rotor position. Meanwhile, a new proportional cost function is developed to obtain the optimal voltage vector. With the proposed control strategy, the necessary position estimation process in the conventional MPCC can be removed, and the MPCC-based sensorless control can be achieved rapidly and steadily, which not only simplifies the whole implementation process but also dramatically improves the system dynamic performance. Besides, the one-beat delay compensation and machine parameter identification are deduced to enhance the control performance of the proposed scheme. Finally, the experiments validate that the proposed sensorless control scheme can achieve excellent control performance for both steady-state and dynamic operations.

Effects of age on listening and postural control during realistic multi-tasking conditions.

Successful performance of balance-related activities requires the effective integration of sensory, cognitive, and motor processes that can be affected by age-related changes. Of these age-related sensory changes, the effects of declines in hearing on balance have not been well-studied despite the fact that hearing loss has now been acknowledged as a significant risk factor for falls. The goal of this study was to evaluate age-related differences in a "standing while listening" task within increasingly challenging conditions resembling those that are often encountered in realistic, everyday situations. This study used a dual-task paradigm in an immersive Virtual Reality street scene setting in which postural load (firm, compliant), listening load (number of talkers), and visual load (eyes open/closed) were manipulated. A multi-talker divided attention listening task was used. Postural performance was assessed using center of pressure (COP) path length, while listening performance was assessed using spoken word recognition accuracy. Results demonstrated that age-related differences were observed in postural performance when postural demands were the highest and in listening performance when listening demands were the highest. Proportional dual-task costs were more pronounced for postural task performance compared to listening task performance and were more pronounced for older compared to younger adults. Postural dual-task costs increased as a function of increasing listening loads. Removal of visual information improved listening task performance across both groups and reduced the dual-task costs to listening in older adults when listening demands were highest (resulting in dual-task benefits). Taken together, the findings support previously documented age-related declines in postural control and auditory processing, demonstrate that increasing listening demands may result in poorer balance, particularly in older adults, and provide additional insights into the interactive effects of age-related declines when sensory, motor, and cognitive challenges are incremented factorially.

Recycling Infrastructure Development under Extended Producer Responsibility in Developing Economies

To tackle the severe pollution caused by electronic waste (e‐waste), several developing countries have introduced e‐waste legislation based on Extended Producer Responsibility (EPR). A major challenge to implement EPR in developing countries is the lack of formal recycling infrastructure. In this paper, we study if a collective form of EPR implementation where producers may jointly invest in recycling facilities can promote their incentives to do so. We develop a Nash bargaining model that captures the decision dynamics underlying joint recycling facility investment. We show that despite its advantage in reducing producers’ fixed investment costs, joint investment in the collective system may lead to a worse recycling infrastructure development outcome than independent investment in an individual system. This can particularly happen when the collective system involves products whose recycling costs are highly differentiated. We further show that cost sharing based on the principle of Individual Producer Responsibility (IPR) may undermine the recycling infrastructure development outcome in the collective system compared to simple proportional cost sharing rules. In practice, it is generally believed that IPR leads to better design incentives than proportional cost sharing rules. Accordingly, our result indicates that there exists a tradeoff between these two cost sharing rules, and promoting recycling infrastructure development via collective systems may come at the expense of design incentives and vice versa.

Acclimatization to Hearing Aids by Older Adults.

Audiologists and hearing aid users (HAUs) generally agree that an adaptation period is needed following the first hearing aid (HA) experience. The main purpose of this study is to investigate the acclimatization of older adult listeners with hearing loss to HAs using listening effort and behavioral measures. Participants (N=47) were older adults with mild to moderately severe sensorineural hearing loss. Thirty-two participants were new HAUs and 15 participants were experienced HAUs. New HAUs were randomly assigned to one of two groups: noise reduction algorithms and directional microphones activated or noise reduction algorithms and directional microphones deactivated. Speech recognition in noise and listening effort were assessed on 8 different occasions during a 10-month period. A dual-task paradigm was used to measure the listening effort deployed to recognize speech in noise. The primary task consisted of the Hearing in Noise Test which also served as the behavioral speech in noise measure. The secondary task was a tactile pattern-recognition task in which participants had to identify a sequence of three tactile stimuli that varied in duration. The two listening effort outcomes were the proportional dual-task cost and the response time on the secondary task. Cognitive abilities, including working memory and speed of processing, were evaluated using the Reading Span Test and the Digit Symbol Substitution Test, respectively. Results show a significant time*group interaction. Both groups of new HAUs showed improvement over time in speech in noise performances (change of ~2 dB signal to noise ratio) and the experienced HAUs did not improve over time. The acclimatization effect was observed over a period of 4 weeks. There was no significant change over time on both measures of listening effort. There was no association between amplitude of acclimatization and the cognitive abilities measured. An acclimatization effect following HA experience was observed. Specifically, the new HAUs displayed a clinically significant change of 2 dB in signal to noise ratio on the Hearing in Noise Test 4 weeks following their initial fitting. The acclimatization effect is not correlated to cognitive abilities.

Power Flow Analysis and Optimization in Ring Distribution Network of Bahawalpur using Newton Raphson Method

Background: The primary motive of an electrical power system is to generate and supply electric power efficiently and reliably to the consumer-end. Transmission losses, system instability and increasing cost in proportion to demand are the main challenges faced in this process. Power flow analysis is required to robustly predict the active / reactive power within the buses, voltage magnitude / phase angles at each bus, cost of transmission and losses well before the practical installation of the power network. Methods/Statistical Analysis: In this paper, we employ power flow analysis using Newton Raphson method and Fast Decoupled method to minimize cost of the electricity and finding optimum active and reactive powers without affecting the voltage regulation. The power flow algorithms are applied for solving the aforementioned load flow problem for ring distribution network of Bahawalpur. We carried out the modeling by obtaining realistic data for constructing bus admittance matrix and specifications of generation units and loads which are connected at the buses. Findings: As a result, optimum flow of power along with the voltage values among different regions of Bahawalpur is obtained. The results from both the algorithms successfully converge and there is an absolute match to validate the accuracy. Novelty: These novel results are of paramount importance since the proposed architecture of Bahawalpur is ring distribution network to replace the existing radial network for improved performance. Furthermore, this research will pave the way for power system planning of Bahawalpur region where all the electrical parameters are known beforehand to design the components according to the requirement. Keywords: Electric power system; voltage magnitude; phase angle; power flow analysis; Newton Raphson method; ring distribution network; active power; reactive power

Optimal dividends and capital injection under dividend restrictions

We study a singular stochastic control problem faced by the owner of an insurance company that dynamically pays dividends and raises capital in the presence of the restriction that the surplus process must be above a given dividend payout barrier in order for dividend payments to be allowed. Bankruptcy occurs if the surplus process becomes negative and there are proportional costs for capital injection. We show that one of the following strategies is optimal: (i) Pay dividends and inject capital in order to reflect the surplus process at an upper barrier and at 0, implying bankruptcy never occurs. (ii) Pay dividends in order to reflect the surplus process at an upper barrier and never inject capital—corresponding to absorption at 0—implying bankruptcy occurs the first time the surplus reaches zero. We show that if the costs of capital injection are low, then a sufficiently high dividend payout barrier will change the optimal strategy from type (i) (without bankruptcy) to type (ii) (with bankruptcy). Moreover, if the costs are high, then the optimal strategy is of type (ii) regardless of the dividend payout barrier. We also consider the possibility for the owner to choose a stopping time at which the insurance company is liquidated and the owner obtains a liquidation value. The uncontrolled surplus process is a Wiener process with drift.