Joint Benefits Research Articles

Novel sensing and joint beam and null steering based resource allocation for cross-tier interference mitigation in cognitive femtocell networks

Cognitive radios and femtocell networks are gaining much popularity due to the formers ability to carry out unlicensed transmission in licensed bands and the latter’s ability to increase the indoor capacity by bringing the transmitter and receiver closer to each other. The combination of the two provides us with a joint benefit of unlicensed transmission and increased system capacity. However, deployments of such cognitive radio based femtocell networks (CRFN) can pose some severe cross-tier interference towards the primary system. In this paper, we propose a novel spectrum sensing technique based on Uniform Linear array (ULA) combined with Genetic Algorithm to detect not only the presence of a Primary user but also estimate its parameters such as range, frequency, angle of arrival and amplitude. Furthermore, a joint beamforming and null steering technique is proposed to maximize the signal to interference plus noise ratio (SINR) towards the secondary user equipment (SUE) while minimizing the interference towards the primary Base Station (PBS). We are reutilizing the sensed uplink (UL) frequency of the Primary users for the downlink (DL) transmission; the cognitive femtocell base station (CFBS) calculates such weight vector that aims at sending the maximum signal power towards the femto user and null in the direction of PBS.

Anticipated international environmental agreements

Consider a situation in which countries anticipate an international environmental agreement (IEA) to be in effect sometime in the future. What is the impact of the future IEA on current emissions after its announcement? We show that the answer to this question is ambiguous.We examine four types of IEAs that aim to reduce pollution stock in the environment. IEA type 1 sets a level of emissions, IEA type 2 and IEA type 3 set a percentage and a uniform cut vis-à-vis the business-as-usual policy respectively. IEA type 4 sets the policy that maximizes future joint benefits of the signatories. We show that all of these agreements reach their goal in the long run, but the intended benefits of these IEAs can potentially be offset by the anticipatory non-cooperative response of the signatories, leading to an environmental degradation in the short run.Which IEA is preferable depends on the targeted level emissions during the phase of cooperation. When this target is above a certain threshold, welfare under IEA type 1 is larger than under IEA type 2 which is larger than under IEA type 3. Moreover, the highest level of welfare that can be attained under IEA type 1 is above the highest level of welfare achieved by any one of the other three IEAs.

Self-reported use of natural health products among rheumatology patients: A cross-sectional survey.

To describe the self-reported use of natural health products (NHPs) and identify characteristics that predict selected NHP use in rheumatology patients. We conducted a cross-sectional survey of consecutive rheumatology patients in two major clinics in Edmonton, Alberta. Survey items included demographic data, rheumatologic diagnoses, prescribed medications, NHPs, and information regarding patients' use of NHPs. Selected NHPs of interest - defined to include joint-specific products, oils with putative joint benefits, and other non-vitamin, non-mineral products - were classified by 2 reviewers. The characteristics of selected NHP users and non-users were compared using chi-squared and ANOVA tests, followed by multivariable-adjusted logistic regression. 1063 patients completed the survey (response rate = 36%, mean age 53 [sd 15], 70% female). 36% of respondents reported using one or more of a wide range of selected NHPs (mean 1.8, range 1-9). The most common source of NHP recommendations for selected NHP users were physicians (42%). Significant predictors of selected NHP use were: being female (aOR 1.41, 95%CI [1.05-1.90], p = 0.02), having a post-secondary degree (aOR 1.60 [1.15-2.22], p = 0.005), and the number of non-rheumatic medications (aOR 1.08 [ 1.00-1.15], p = 0.03) and NSAIDs (aOR 1.32 [1.06, 1.63], p = 0.01). Similar findings were observed among only inflammatory arthritis patients. Our study confirms the frequent use of selected NHPs, possibly to mitigate persistent symptoms of rheumatologic illness. Rheumatologists appear to be trusted sources of advice and recommendations on NHP use and should provide balanced counselling for their patients.

Enabling a Freight Traffic Controller for Collaborative Multidrop Urban Logistics

There is increasing interest in how horizontal collaboration between parcel carriers might help alleviate problems associated with last-mile logistics in congested urban centers. Through a detailed review of the literature on parcel logistics pertaining to collaboration, along with practical insights from carriers operating in the United Kingdom, this paper examines the challenges that will be faced in optimizing multi-carrier, multidrop collection, and delivery schedules. A “freight traffic controller” (FTC) concept is proposed. The FTC would be a trusted third party, assigned to equitably manage the work allocation between collaborating carriers and the passage of vehicles over the last mile when joint benefits to the parties could be achieved. Creating this FTC concept required a combinatorial optimization approach for evaluation of the many combinations of hub locations, network configuration, and routing options for vehicle or walking to find the true value of each potential collaboration. At the same time, the traffic, social, and environmental impacts of these activities had to be considered. Cooperative game theory is a way to investigate the formation of collaborations (or coalitions), and the analysis used in this study identified a significant shortfall in current applications of this theory to last-mile parcel logistics. Application of theory to urban freight logistics has, thus far, failed to account for critical concerns including ( a) the mismatch of vehicle parking locations relative to actual delivery addresses; ( b) the combination of deliveries with collections, requests for the latter often being received in real time during the round; and ( c) the variability in travel times and route options attributable to traffic and road network conditions.

Experimental test of oyster restoration within eelgrass

Abstract Both seagrasses and oysters are foundation species valued for their wide range of ecosystem services, but their space competition sets a constraint on joint benefits. A reserve for native Olympia oysters (Ostrea lurida) was established in lower Hood Canal (Washington State, USA) more than a century ago but is now devoid of that species and dominated by native eelgrass (Zostera marina). This situation sets up a conservation conflict because management activities for one species are at odds with the protection of another. In experimental enhancement plots, Olympia oysters were outplanted at low density, which successfully maintained eelgrass density and production. One method was used in 2013 (seeded cultch, 8% cover) and two additional methods in 2015 (anchored cultch and single oysters, the latter at 4% cover). For all outplant methods, oysters experienced 99% annual mortality, associated with the attraction of non‐native and native predators. Shell cover remained steady for a year and then declined rapidly, as shell accumulation did not exceed sedimentation rates. Eelgrass per se does not preclude Olympia oysters, given that the two species were observed to co‐occur at a coastal estuarine site (Willapa Bay, Washington). However, even when socio‐political constraints on restoration activities were overcome, ecological constraints remained from predation. Competition between these two protected species was avoided, but it may be the case that top‐down control on oysters was particularly acute owing to low oyster density and/or the environmental conditions of eelgrass beds.

Evaluating joint environmental and cost performance in municipal waste management systems through data envelopment analysis: Scale effects and policy implications

The widespread need to reduce public expenditure and meet the targets for separate collection established by current national and European legislation requires regulatory authorities to reorganize their municipal waste management systems to improve both their economic and environmental performance. This process can be helped to a great extent by the availability of empirical measures of comparative efficiency. Adding to the literature that evaluates this through data envelopment analysis (DEA) – usually focused on economic (cost) efficiency alone – this article proposes a joint evaluation of the two aspects through a modified DEA model that includes unsorted waste as an undesired output to be minimized. The article also provides an application using data for 289 municipalities located in an Italian region, Abruzzo, for the period 2011–2013. The main focus of the empirical analysis is on dimensional aspects. In particular, comparing the results obtained through DEA models based on different hypotheses concerning returns to scale, in the first place it is verified whether a particular municipal dimension emerges as an efficient benchmark, and secondly if waste collection is organized above or below its optimal scale in the municipalities taken into consideration. Tobit and probit regression models are then applied to some of the results to isolate the influence of territorial specificities on different kinds of scale inefficiencies. The information obtained allows to shed light on the usefulness of designing multi-municipal optimal territorial areas (OTAs) to improve the joint benefits of environmental and cost efficiency in waste collection, and to understand which variables the regulator should preferably take into account in the process.

The effect of code-sharing alliances on airline profitability

Code sharing and global alliances both have been increasingly adopted by airlines worldwide in recent years. A growing number of airlines, therefore, are embedded in networks of multilateral “coopetitive” (i.e., cooperative, but competitive) relationships that influence their product offering, pricing strategies, operating efficiency, market power, and their overall successes. There has been considerable research analyzing the benefits for airlines from joining global alliances, including bilateral code-sharing partnerships. However, the joint effect of code-sharing and global alliances on airline performance has not been fully investigated. In this paper, we study how the use of code-sharing strategies and their structural embeddedness into global alliances may impact airline performance. Using a unique dataset compiled from Flight Global and Airline Business's Annual Airline Alliance Report, the paper empirically investigates the joint benefits of code-sharing partnerships and global alliances on airline profitability. The results based on a group of 81 airlines during the 2007–2012 period show that the profit margin of an airline is positively associated with the number of code-sharing partners it has. Furthermore, the profit margin gains from code-sharing are greater when an airline has a higher proportion of its code-sharing partners in the same global alliance; i.e., allied code-sharing partners. Finally, we find no significant evidence that the percent of comprehensive code sharing partnerships to total partnerships has an impact on profit margin.

Hybrid Bit-to-Symbol Mapping for Spatial Modulation

In spatial modulation (SM), the information bit stream is divided into two different sets: the transmit antenna index bits (TA-bits) and the amplitude and phase modulation bits (APM-bits). However, the conventional bit-to-symbol mapping (BTS-MAP) scheme maps the APM-bits and the TA-bits independently. For exploiting their joint benefits, we propose a new BTS-MAP rule based on the traditional 2-D Gray mapping rule, which increases the Hamming distance (HD) between the symbol pairs detected from the same transmit antenna (TA) and simultaneously reduces the average HD between the symbol pairs gleaned from different TAs. Based on the analysis of the distribution of minimum Euclidean distance (MED) of SM constellations, we propose a criterion for the construction of a meritorious BTS-MAP for a specific SM setup, with no need for additional feedback links or extra computational complexity. Finally, Monte Carlo simulations are conducted for confirming the accuracy of our analysis.

Effect of Intraarticular Triamcinolone Acetonide Injection for Wrist Pain in Rheumatoid Arthritis Patients: A Statistical Investigation.

A significant number of patients on long-term treatment and users of biologics complain of wrist pain due to synovial proliferation and arthropathic changes. Synovectomy or joint arthroplasty is often indicated for such patients, but many refuse surgery. For these patients triamcinolone acetonide was injected into the dorsum of the wrist, and evaluated the clinical benefit and safety of the wrist joint. We injected triamcinolone acetonide into the dorsum of the wrist. We evaluated the clinical benefit and safety of intraarticular triamcinolone acetonide by analyzing data on (1) the number of injections, (2) decrease in visual analog scale pain, (3) changes in carpal height ratio, radio carpal distance ratio, and radial rotation angle in X-ray imaging, and (4) the adverse reactions of triamcinolone acetonide injection on the subcutaneous tissue and extensor tendons. 1. The number of injections per patient over 3 years 8 months was 1 for 44 wrists, 2 for 21 wrists, 3 for 17 wrists, 4 for 6 wrists, 5 for 3 wrists, 6 for 3 wrists, 7 for 2 wrists, 9 for 2 wrists, 12 for 4 wrists, and 13 for 1 wrist. 2. The overall mean VAS improved from 79 mm at baseline to 11 mm post-injection. 3. In the grade I and II group, CHS, RCDR and RRA were not statistically significant. In the grade III and IV group, CHR showed a significant decrease. 4. Neither subcutaneous atrophy nor extensor tendon rupture was reported. More than 90% of patients of all disease grades responded to an average of 1 to 4 injections per year.

Anticipated International Environmental Agreements

Consider a situation in which countries anticipate an international environmental agreement (IEA) to be in effect sometime in the future. What is the impact of the future IEA on current emissions after its announcement? We show that the answer to this question is ambiguous. We examine four types of IEAs that aim to reduce pollution stock in the environment. IEA type 1 sets a level of emissions, IEA type 2 and IEA type 3 set a percentage and a uniform cut vis-a-vis the business-as-usual policy respectively. IEA type 4 sets the policy that maximizes future joint benefits of the signatories. We show that all of these agreements reach their goal in the long run, but the intended benefits of these IEAs can potentially be offset by the anticipatory non-cooperative response of the signatories, leading to an environmental degradation in the short run. Which IEA is preferable depends on the targeted level emissions during the phase of cooperation. When this target is above a certain threshold, welfare under IEA type 1 is larger than under IEA type 2 which is larger than under IEA type 3. Moreover, the highest level of welfare that can be attained under IEA type 1 is above the highest level of welfare achieved by any one of the other three IEAs.

Does performance disclosure influence physicians’ medical decisions? An experimental study

Quality improvements in markets for medical care are key objectives in any health reform. An important question is whether disclosing physicians’ performance can contribute to achieving these goals. Due to the asymmetric information inherent in medical markets, one may argue that changes in the information structure are likely to influence the environment in which health care providers operate. In a laboratory experiment with medical students that mimics a physician decision-making environment we analyze the effect of disclosing performance information to peers. Our results suggest that the information structure does influence the individual physician's supply of medical services. Under performance disclosure, choices that are in accordance with the medical norm or maximize the joint benefit become more frequent.

Meritocracy, egalitarianism and the stability of majoritarian organizations

Egalitarianism and meritocracy are competing principles to distribute the joint benefits of cooperation. We examine the consequences of letting members of society vote between those two principles, in a context where individuals must join with others into coalitions of a certain size to become productive. Our setup induces a hedonic game of coalition formation. We study the existence of core stable partitions (organizational structures) of this game. We show that the inability of voters to commit to one distributional rule or another is a potential source of instability. But we also prove that, when stable organizational structures exist, they may be rich in form, and different than those predicted by alternative models of coalition formation. Non-segregated coalitions may arise within core stable structures. Stability is also compatible with the coexistence of meritocratic and egalitarian coalitions. These phenomena are robust, and persist under alternative variants of our initial model.

La innovación en la empresa a través del abastecimiento estrategico. Una revisión de la literatura

Innovation is considered to be a strategic action to be realized by companies, especially in recent years (Schumpeter, 2000). The action of innovating has generated competitive advantages for businesses; additionally, it depends on and influences different areas within organizations. In this paper, it is argued the possibility of generating innovations in a company through the technological management of its supply chain; specifically, making rational use of the strategic sourcing. The strategic sourcing is a systematic method, based on facts, to optimize the delivery of all types of inputs within a company and aims to improve the value proposition for its customers (University of Michigan, 2013). Although strategic sourcing has several aspects, one of those with the greatest impact on the business is the selection and development of suppliers. Through this article, the need of linking the concepts of Technological Innovation and Strategic Sourcing is developed, stressing out the relationship among these concepts, showing the necessity to include factors that generate innovation in the methods for selection of suppliers and vendors. This work suggests that strategic innovation-capacity of suppliers and customers will bring joint benefits to the members of a supply chain.

A decision-making framework to integrate maintenance contract conditions with critical spares management

Maintenance outsourcing is a strategic driver for asset intensive industries pursuing to enhance supply chain performance. Spare parts management plays a relevant role in this premise since its significant impact on equipment availability, and hence on business success. Designing critical spares policies might therefore seriously affect maintenance contracts profitability, yet service receivers and external providers traditionally attempt to benefit separately. To coordinate both chain parties, we investigated whether the spare components pool should be managed in-house or contracted out. This paper provides a decision-making framework to efficiently integrate contractual conditions with critical spares stockholding. Using an imperfect maintenance strategy over a finite horizon, the scheme maximizes chain returns whilst evaluating the impact of an additional part to stock. As result, an original joint value – preventive interval and stock level – sets the optimal agreement to profitably allocate the components pool within the service contract. Subsidization bonuses on preventive interventions and pooling costs are also estimated to induce the service provider to adjust its policy when needed. The proposed contractual conditions motivate stakeholders to continuously improve maintenance performance and supply practices, thus obtaining higher joint benefits.

Dynamic Indexing: Leakage-Aging Co-Optimization for Caches

Traditional implementations of low-power states based on voltage scaling or power gating have been shown to have a beneficial effect on the aging phenomena caused by negative bias temperature instability (NBTI), which can be explained in terms of the intuitive correlation between the idleness and the reduced workload of a system. Such a joint benefit has been exploited only partially because of the different nature of energy and aging as cost functions: as a performance figure, aging is affected by the worst idleness pattern. Therefore, large potential energy savings usually result in limited aging reductions. In this paper, we address this problem in the context of power-managed caches, which represent a critical target for NBTI-reduced aging: given their symmetric structure, SRAM structures are, in particular, sensitive to NBTI effects because they cannot take advantage of the value-dependent recovery typical of NBTI. We propose a strategy called dynamic indexing, in which the cache indexing function is changed over time in order to uniformly distribute the idleness over all the various power managed units (e.g., lines). This distribution allows fully using the leakage optimization potential and extending the lifetime of a cache. We explore various alternatives, in particular different granularities of the power managed units as well as different reindexing functions. Experimental analysis shows that it is possible to simultaneously reduce leakage power and aging in caches, with minimal power consumption overhead.

Patterns of Epistasis between Beneficial Mutations in an Antibiotic Resistance Gene

Understanding epistasis is central to biology. For instance, epistatic interactions determine the topography of the fitness landscape and affect the dynamics and determinism of adaptation. However, few empirical data are available, and comparing results is complicated by confounding variation in the system and the type of mutations used. Here, we take a systematic approach by quantifying epistasis in two sets of four beneficial mutations in the antibiotic resistance enzyme TEM-1 β-lactamase. Mutations in these sets have either large or small effects on cefotaxime resistance when present as single mutations. By quantifying the epistasis and ruggedness in both landscapes, we find two general patterns. First, resistance is maximal for combinations of two mutations in both fitness landscapes and declines when more mutations are added due to abundant sign epistasis and a pattern of diminishing returns with genotype resistance. Second, large-effect mutations interact more strongly than small-effect mutations, suggesting that the effect size of mutations may be an organizing principle in understanding patterns of epistasis. By fitting the data to simple phenotype resistance models, we show that this pattern may be explained by the nonlinear dependence of resistance on enzyme stability and an unknown phenotype when mutations have antagonistically pleiotropic effects. The comparison to a previously published set of mutations in the same gene with a joint benefit further shows that the enzyme's fitness landscape is locally rugged but does contain adaptive pathways that lead to high resistance.

Cooperate “and” compete: coopetition strategy in retailer‐supplier relationships

PurposeThis study aims to examine the strategic implications and managerial outcomes of the concurrent use of cooperation and competition in vertical channel relationships.Design/methodology/approachThis study employs a structured questionnaire to gather data regarding vertical channel relationships in China.FindingsWhereas the academic literature has emphasized cooperation between channel members because of the interdependence between them, in reality, retailers may accept competition as just another part of doing business with suppliers.Research limitations/implicationsThe outcome variables used may not be comprehensive. In particular, the authors choose the flexibility of channel resources to stand for private benefits and joint benefits to represent common benefits, and though these variables certainly represent the intended benefits of the ambidextrous strategy, it remains to be seen whether other benefits may emerge for the exchange parties in vertical relationships.Practical implicationsUsing an ambidextrous strategy does not damage relationship quality, though it certainly does not enhance it. This view is based on the notion that an ambidextrous strategy at least does not harm either common or private benefits. Therefore, exchange parties using the ambidextrous strategy should not experience a relationship that is worse than that which results when they use cooperation or competition alone. The results of the current study indicate that this view reflects reality more accurately.Originality/valueThe value of the current study centers on the application of a conceptual framework regarding ambidextrous strategy to vertical channel relationships in a developing economy.

To Allot Secrecy-Safe Association Rules Mining Schema Using FP Tree

Association rules mining is a frequently used technique which finds interesting association and correlation relationships among large set of data items which occur frequently together. Nowadays, data collection is ubiquitous in social and business areas. Many companies and organi¬zations want to do the collaborative association rules mining to get the joint benefits. However, the sensitive information leakage is a problem we have to solve and privacy- preserving techniques are strongly needed. In this paper, we focus on the privacy issue of the association rules mining and propose a secure frequent-pattern tree (FP-tree) based scheme to pre- serve private information while doing the collaborative association rules mining. We display that our schema is secure and collusion-resistant for n parties, which means that even if n - 1 dishonest party collude with a dishonest data miner in an attempt to learn the associations’ rules between honest respondents and their responses, they will be unable to success.

Meritocracy, Egalitarianism and the Stability of Majoritarian Organizations

Egalitarianism and meritocracy are competing principles to distribute the joint benefits of cooperation. We examine the consequences of letting members of society vote between those two principles, in a context where individuals must joint with others into coalitions of a certain size to become productive. Our setup induces a hedonic game of coalition formation. We study the existence of core stable partitions (organizational structures) of this game. We show that the inability of voters to commit to one distributional rule or another is a potential source of instability. But we also prove that, when stable organizational structures exist, they may be rich in form, and different than those predicted by alternative models of coalition formation. Non-segregated coalitions may arise within core stable structures. Stability is also compatible with the coexistence of meritocratic and egalitarian coalitions. These phenomena are robust, and persist under alternative variants of our initial model.

Sequential multi-agent exploration for a common goal

Motivated by applications in Dynamic Spectrum Access Networks, we focus on a system in which a few agents are engaged in a costly individual exploration process where each agent's benefit is determined according to the minimum obtained value. Such an exploration pattern is applicable to many systems, including shipment and travel planning. This paper formally introduces and analyzes a sequential variant of the general model. According to that variant, only a single agent engages in exploration at any given time, and when an agent initiates its exploration, it has complete information about the minimum value obtained by the other agents so far. We prove that the exploration strategy of each agent, according to the equilibrium of the resulting Stackelberg game, is reservation-value based, and show how the reservation values can be calculated. We also analyze the agents' expected-benefit maximizing exploration strategies when they are fully cooperative i.e., when they aim to maximize the expected joint benefit. The equilibrium strategies and the expected benefit of each agent are illustrated using a synthetic homogeneous environment, thereby demonstrating the properties of this new exploration scheme and the benefits of cooperation.