Fly with me : algorithms and methods for influencing a flock

As robots become more affordable, they will begin to exist in the world in greater quantities. Some of these robots will likely be designed to act as components in specific teams. These teams could work on tasks that are too large or complex for a single robot - or that are merely more efficiently accomplished by a team - such as surveillance in a large building or product delivery to packers in a warehouse. Multiagent systems research studies how these teams are formed and how they work together. Ad hoc teamwork, a newer area of multiagent systems research, studies how new robots can join these pre-existing teams and assist the team in accomplishing its goal. This dissertation extends and applies research in ad hoc teamwork towards the general area of flocking, which is an emergent swarm behavior. In particular, the work in this dissertation considers how ad hoc agents - called influencing agents in this dissertation - can join a flock, be recognized by the rest of the flock as part of the flock, influence the flock towards particular behaviors through their own behavior, and then separate from the flock. Specifically, the primary research question addressed in this dissertation is How can influencing agents be utilized in various types of flocks to influence the flock towards a particular behavior? In order to address this research question, this dissertation makes six main types of contributions. First, this dissertation formalizes the problem of using influencing agents to influence a flock. Second, this dissertation contributes and analyzes algorithms for influencing a flock to a desired orientation. Third, this dissertation presents methods for determining how to best add influencing agents to a flock. Fourth, this dissertation provides methods by which influencing agents can join and then leave a flock in motion. Fifth, this dissertation evaluates some of the influencing agent algorithms on a robot platform. Sixth, although the majority of this dissertation assumes the influencing agents will join a flock that behaves similarly to European starlings, this dissertation also provides insight into when and how its algorithms are generalizable to other types of flocks as well as to general teamwork and coordination research. All of the methods presented in this dissertation are empirically evaluated using a simulator that can support large flocks.Computer Science

A Survey of Ad Hoc Teamwork: Definitions, Methods, and Open Problems

Ad hoc teamwork is the well-established research problem of designing agents that can collaborate with new teammates without prior coordination. This survey makes a two-fold contribution. First, it provides a structured description of the different facets of the ad hoc teamwork problem. Second, it discusses the progress that has been made in the field so far, and identifies the immediate and long-term open problems that need to be addressed in the field of ad hoc teamwork

Back to the Future: A Century of Compensation

What were the hot compensation issues and practices over the past century? Does history offer any lessons that may inform our compensation decisions in the future? To answer these questions, we reviewed newspapers and business publications from the past 100 years. To highlight changes in compensation systems during that time, we selected four topics to examine in detail in this paper: compensation\u27s role in the changing nature of the deal; the evolution of pay-for-performance; the emergence of benefits; and the bellwethers of compensation systems. Four lessons for the future are drawn. These include: End the search for the one right compensation strategy; Understand what in the context matters; Continue pragmatic experimentation, and Support continuous learning about compensation. Readers are invited to delve into the history of compensation to discover what they take away for the future

Making friends on the fly : advances in ad hoc teamwork

textGiven the continuing improvements in design and manufacturing processes in addition to improvements in artificial intelligence, robots are being deployed in an increasing variety of environments for longer periods of time. As the number of robots grows, it is expected that they will encounter and interact with other robots. Additionally, the number of companies and research laboratories producing these robots is increasing, leading to the situation where these robots may not share a common communication or coordination protocol. While standards for coordination and communication may be created, we expect that any standards will lag behind the state-of-the-art protocols and robots will need to additionally reason intelligently about their teammates with limited information. This problem motivates the area of ad hoc teamwork in which an agent may potentially cooperate with a variety of teammates in order to achieve a shared goal. We argue that agents that effectively reason about ad hoc teamwork need to exhibit three capabilities: 1) robustness to teammate variety, 2) robustness to diverse tasks, and 3) fast adaptation. This thesis focuses on addressing all three of these challenges. In particular, this thesis introduces algorithms for quickly adapting to unknown teammates that enable agents to react to new teammates without extensive observations. The majority of existing multiagent algorithms focus on scenarios where all agents share coordination and communication protocols. While previous research on ad hoc teamwork considers some of these three challenges, this thesis introduces a new algorithm, PLASTIC, that is the first to address all three challenges in a single algorithm. PLASTIC adapts quickly to unknown teammates by reusing knowledge it learns about previous teammates and exploiting any expert knowledge available. Given this knowledge, PLASTIC selects which previous teammates are most similar to the current ones online and uses this information to adapt to their behaviors. This thesis introduces two instantiations of PLASTIC. The first is a model-based approach, PLASTIC-Model, that builds models of previous teammates' behaviors and plans online to determine the best course of action. The second uses a policy-based approach, PLASTIC-Policy, in which it learns policies for cooperating with past teammates and selects from among these policies online. Furthermore, we introduce a new transfer learning algorithm, TwoStageTransfer, that allows transferring knowledge from many past teammates while considering how similar each teammate is to the current ones. We theoretically analyze the computational tractability of PLASTIC-Model in a number of scenarios with unknown teammates. Additionally, we empirically evaluate PLASTIC in three domains that cover a spread of possible settings. Our evaluations show that PLASTIC can learn to communicate with unknown teammates using a limited set of messages, coordinate with externally-created teammates that do not reason about ad hoc teams, and act intelligently in domains with continuous states and actions. Furthermore, these evaluations show that TwoStageTransfer outperforms existing transfer learning algorithms and enables PLASTIC to adapt even better to new teammates. We also identify three dimensions that we argue best describe ad hoc teamwork scenarios. We hypothesize that these dimensions are useful for analyzing similarities among domains and determining which can be tackled by similar algorithms in addition to identifying avenues for future research. The work presented in this thesis represents an important step towards enabling agents to adapt to unknown teammates in the real world. PLASTIC significantly broadens the robustness of robots to their teammates and allows them to quickly adapt to new teammates by reusing previously learned knowledge.Computer Science

Pehkun kunnon vaikutus broilerin ja broileriemojen jalkapohjaterveyteen ja korotettujen ritilätasojen vaikutus broilerin jalkaterveyteen

Contact dermatitis in broilers is a multifactorial condition that is most commonly caused by poor litter quality or otherwise unsuitable material affecting the footpad or hock skin. Footpad health is mainly maintained by keeping litter in a dry and friable condition. Hence, footpad lesions reflect litter quality that, more widely, describes the housing conditions and bird health. The evaluation of the prevalence of contact dermatitis denotes a commonly accepted approach to assess the welfare of broiler flocks. However, there is lack of knowledge about footpad lesions in broiler breeders. Although numerous studies on the effect of litter materials on footpad condition have been conducted, experiments with peat are scarce. Also, knowledge of the influence of peat on hock burns and litter quality is lacking. Modern fast-growing broilers spend excessive time resting and this inactivity has been suggested to increase the incidence of impaired gait and leg disorders. Tibial dyschondroplasia (TD) is one of the most common leg pathologies in broilers. Perches or elevated platforms add complexity to the broilers’ environment and may stimulate locomotion. However, research on the use of elevated structures under commercial rearing conditions and possible benefits for broiler leg health is limited. This thesis provides descriptive information about contact dermatitis and breast blisters in broiler breeders throughout the production period with respect to litter condition. Secondly, the study compared the influence of peat bedding with wood shavings and ground straw (fine crushed straw) on contact dermatitis and plumage cleanliness in fast-growing broilers and litter condition in commercial broiler houses. Furthermore, the study examined the use of perches and elevated platforms by broilers, and the impact of the additional equipment on contact dermatitis, plumage cleanliness, walking ability, the occurrence of TD and litter conditions under intensive rearing circumstances. Litter condition in broiler and breeder houses was evaluated according to the Welfare Quality® (WQ) protocol for broiler chicken. Additionally, litter height was measured, and litter quality determined according to moisture, pH and ammonia content. Footpad condition was visually inspected with the WQ-scoring method (broilers), the official Finnish system (broilers) or employing a method modified from the official system (breeders). Hock skin lesions and plumage cleanliness were assessed according to the WQ-protocol. Broiler gait was scored before slaughter following the WQ-protocol. The severity of TD was determined. The use of perches and platforms was monitored by video recording. Additionally, farmers estimated the platform and perch usage twice a week throughout the growing period. The condition of breeder footpads deteriorated towards the end of the production period, with the occurrence of severe lesions reaching a maximum of 64% on average at slaughter. However, hock burns and breast blisters were rarely recorded. The litter layer became drier over time. Although dry and friable litter in breeder houses was associated with healthier footpads, other factors were of greater importance, as footpad lesions, particularly severe lesions, appeared more often towards slaughter age. Broiler footpads were generally in good condition at slaughter age, 80% of the birds having healthy footpads. In broilers, hock burns were more frequently detected than footpad lesions. Inferior footpad and hock skin health was scored on wood shavings rather than on peat, without differences in litter condition and moisture. Moreover, the lack of difference in moisture between ground straw and peat still resulted in poorer litter, footpad and hock skin condition on ground straw. Farms differed for footpad and hock burn condition, and litter quality. In risk analysis, the impact of farmer on contact dermatitis severity exceeded the effect of litter quality. The platforms were used frequently while only single birds used perches. The study indicated no effects of platform treatment on footpad and hock skin health, and litter condition. The birds with access to platforms, however, had enhanced leg health: mean gait score, the percentage of birds scored 3, and TD percentage and severity were lower for birds in platform-equipped houses. Access to platforms most likely enables more versatile movement, such as walking forward, up and down, grasping by feet, and jumping, which may promote leg health and gait. This was the first study to follow footpad health in broiler breeders through the whole production period. The results indicate the need for further investigation because good litter condition alone appears insufficient to keep breeder footpads healthy for their entire life. Further, this thesis provides new knowledge about the applicability of peat as broiler bedding. According to our results, regarding footpad health, peat seems to be the optimal litter material for Finnish conditions. Furthermore, the study underlines the importance of farmer ability to manage litter conditions, regardless of the chosen litter material. Hock burn monitoring could represent a more sensitive indicator of litter condition and possibly also signal leg health status, therefore monitoring hock burns at slaughter should be considered. The advantages of traditional perches for broilers should be re-evaluated as they remained largely unused. However, the extensive use of platforms suggests that broilers are motivated to perch on elevated structures. Hence, platform availability could enhance their emotional wellbeing. Elevated platforms offering additional possibilities for locomotion seem promising because they show apparent potential to enhance leg health without compromising litter condition or footpad health. Based on all these findings, elevated platforms with ramps can be recommended as a way forward to enhance broiler welfare in commercial environments.Broilereiden jalkapohjien ja kintereiden iholla yleinen kontakti-ihottuma syntyy kosketuksesta huonokuntoiseen kuivikepohjaan tai muuten sopimattomaan pohjamateriaaliin. Tärkeimpänä ihovaurioita ennaltaehkäisevänä tekijänä pidetään hyväkuntoista ja kuivaa kuivikepohjaa eli pehkua. Jalkapohjavaurioiden arvostelua käytetään paitsi parven ja yksilön hyvinvoinnin myös kasvatusolosuhteiden onnistumisen arvioinnissa. Eri kuivikemateriaalien vaikutuksia jalkapohjaterveyteen on tutkittu runsaasti, mutta suomalaisen broilerituotannon yleisimmästä kuivikkeesta, turpeesta, on vähän tutkimustietoa. Broileriemojen jalkapohjaterveyttä on toistaiseksi tutkittu hyvin vähän. Nopea kasvu ja vähäinen liikunta huonontavat broilerin kävelykykyä ja altistavat jalkavioille, kuten esimerkiksi sääriluun kasvuruston luutumishäiriölle. Kasvattamoon sijoitetuilla orsilla on mahdollista parantaa broilerien liikkuvuutta. Tutkimustietoa tarvitaan siitä, miten linnut käyttävät orsia käytännön tilaolosuhteissa ja onko orsilla vaikutusta pehkun kuntoon, kontakti-ihottuman esiintymiseen ja jalkaterveyteen. Väitöskirjassa kartoitettiin ensimmäistä kertaa emojen jalkapohjaterveyttä ja kuivikepohjan kuntoa läpi koko tuotantokauden. Lisäksi selvitettiin, vaikuttaako kuivikemateriaalin valinta broilereiden jalkapohjatulehdusten ja kinnerpalamien esiintymiseen ja pehkun kuntoon. Kuivikkeista verrattiin turvetta kutteriin ja hienojakoiseen olkikuivikkeeseen. Väitöskirjassa tutkittiin lisäksi, miten broilerit käyttävät kasvattamoon sijoitettuja orsia ja ritilätasoja sekä näiden vaikutusta pehkun kuntoon, kontakti-ihottuman yleisyyteen ja jalkaterveyteen. Tutkituissa broileriemokanaloissa kuivikepohja pysyi koko tuotantokauden ajan hyvässä tai melko hyvässä kunnossa. Pehkun kosteus aleni tuotantokauden edetessä. Jalkapohjavauriot, varsinkin vakavat muutokset, yleistyivät iän myötä. Vakavia vaurioita todettiin teurasiässä keskimäärin 64 %:lla tutkituista broileriemoista. Vaikka huonokuntoisempi ja kosteampi kuivikepohja lisäsi jalkapohjavaurioiden määrää, tulosten perusteella näyttää siltä, että pelkästään kuiva ja irtonainen pehku ei riitä pitämään emojen jalkapohjia terveinä koko tuotantokautta. Tutkituissa broileriparvissa lintujen jalkapohjat olivat keskimäärin hyvässä kunnossa, terveiden jalkapohjien osuus oli noin 80 %. Kinnerpalamia esiintyi jalkapohjavaurioita enemmän, keskimäärin 32 %:lla linnuista. Vaikka turve- ja kutteripohjan kunto ja kosteus eivät eronneet, turpeella esiintyi vähemmän kontakti-ihottumaa. Olkikuivike- ja turvepehkun kosteudessa ei todettu eroa, mutta olkikuivikepohjan kunto oli huonompi ja kontakti-ihottumaa esiintyi sillä enemmän. Tilojen väliset erot olivat merkittäviä, joten tuottajan rooli olosuhteiden hallinnassa on keskeinen. Broilerit käyttivät rampillisia ritilätasoja mielellään, mutta orsien käyttö oli vähäistä. Ritilätasojen avulla näyttäisi olevan mahdollista parantaa broilereiden jalkaterveyttä: ritiläparvilla todettiin parempi kävelykyky, vähemmän ontuvia lintuja ja sääriluun kasvuruston luutumishäiriötä. Ritilöiden vaikutus pehkun ja jalkapohjien kuntoon näytti olevan hallittavissa oikeilla olosuhdesäädöillä. Kaikki tutkimukset tehtiin suomalaisilla tuotantotiloilla, joten tulosten käytännön merkitys on suuri. Tuottajien ja tutkijoiden innovatiivista yhteistyötä tarvitaan jatkossakin, jotta saataisiin selville mistä emojen jalkapohjamuutokset juontuvat ja millaisin keinoin jalkavaurioista päästään eroon. Turvepehkulla broilerilla kontakti-ihottumaa esiintyi vähemmän kuin kutterilla ja olkikuivikkeella, mutta tuottajan ammattitaidon merkitys oli kuitenkin kuivikemateriaalia suurempi. Broilerilla kinnerpalamat saattaisivat olla jalkapohjavaurioita herkempi mittari kertomaan pehkuolosuhteista tai esimerkiksi jalkaterveydestä, joten kinnerpalamien esiintymistä olisi hyvä seurata säännöllisesti. Koska broilerit käyttivät ritilöitä innokkaasti, ritilätasojen käytön edistäminen broilerikasvattamoissa olisi tutkimuksen perusteella suositeltavaa

Software Startups -- A Research Agenda

Software startup companies develop innovative, software-intensive products within limited time frames and with few resources, searching for sustainable and scalable business models. Software startups are quite distinct from traditional mature software companies, but also from micro-, small-, and medium-sized enterprises, introducing new challenges relevant for software engineering research. This paper's research agenda focuses on software engineering in startups, identifying, in particular, 70+ research questions in the areas of supporting startup engineering activities, startup evolution models and patterns, ecosystems and innovation hubs, human aspects in software startups, applying startup concepts in non-startup environments, and methodologies and theories for startup research. We connect and motivate this research agenda with past studies in software startup research, while pointing out possible future directions. While all authors of this research agenda have their main background in Software Engineering or Computer Science, their interest in software startups broadens the perspective to the challenges, but also to the opportunities that emerge from multi-disciplinary research. Our audience is therefore primarily software engineering researchers, even though we aim at stimulating collaborations and research that crosses disciplinary boundaries. We believe that with this research agenda we cover a wide spectrum of the software startup industry current needs