Energy Harvesting in Wireless Applications

The objective of this thesis has been to study how extensive current research has gone within energy harvesting and to investigate a solution for making the OLP425 (a sensor module developed by ConnectBlue AB) independent of a conventional battery as energy source, whilst staying wireless. This has been done by investigating the amounts of energy that is available from our surroundings (e.g. solar´radiation, thermal gradients, and radio waves) and how suitable the methods are for supplying the OLP425. A solution based on a photovoltaic cell was chosen and an electrical circuit was designed around it, powering the OLP425 and recharging a Li-ion rechargeable battery. It was successful in powering the OLP425 but limited by the sensor module’s duty cycle. Whilst being a successful solution there is still more to investigate in the field that includes other energy harvesting methods where some require a larger business model to implement

SZZ Unleashed: An Open Implementation of the SZZ Algorithm -- Featuring Example Usage in a Study of Just-in-Time Bug Prediction for the Jenkins Project

Numerous empirical software engineering studies rely on detailed information about bugs. While issue trackers often contain information about when bugs were fixed, details about when they were introduced to the system are often absent. As a remedy, researchers often rely on the SZZ algorithm as a heuristic approach to identify bug-introducing software changes. Unfortunately, as reported in a recent systematic literature review, few researchers have made their SZZ implementations publicly available. Consequently, there is a risk that research effort is wasted as new projects based on SZZ output need to initially reimplement the approach. Furthermore, there is a risk that newly developed (closed source) SZZ implementations have not been properly tested, thus conducting research based on their output might introduce threats to validity. We present SZZ Unleashed, an open implementation of the SZZ algorithm for git repositories. This paper describes our implementation along with a usage example for the Jenkins project, and conclude with an illustrative study on just-in-time bug prediction. We hope to continue evolving SZZ Unleashed on GitHub, and warmly invite the community to contribute

Report on the excavation of a Punic tomb

On 19th November 2001, while two of us (DB, NJC) were preparing a drawn record of the Punic tomb that is situated on Bajda Ridge, Xemxija, a small ceramic bowl (100211) was uncovered from below a few centimetres of soil that covered the inner part of the threshold to the rock-cut chamber (Fig. 1). An official from the Museums Department was informed of the discovery on the same day and a site inspection was carried out. It was realised that more artefacts could lie undisturbed within the chamber and a decision was taken to excavate the deposit. Authorisation for the Department of Classics and Archaeology, University of Malta, to undertake the excavation was received from the Director, Museums Department, and the excavation was completed on the 22nd November. The tomb is located on the ridge, near a path that diverges eastwards from the track that links Pwales valley to the Mistra valley. It is cut in the Upper Coralline limestone that outcrops in the area on a North-South axis and consists of a sub-rectangular chamber that is reached through a low entrance at the bottom of a rectangular shaft (Fig. 1). The tomb appears in an inventory for the first time in 1996 when it was listed in the survey of archaeological sites prepared by Malta University Services for the Planning Authority by Anthony Bonanno in connection with the preparation of the North-West local plan for Malta. The tomb had been examined and photographed by one of us (NCV) in 1992. At the time, it was littered with debris and it was only with difficulty that a view of the chamber could be achieved through the entrance that was partly concealed by an irregular blocking stone. Late in 2000, members of the St Paul's Bay Heritage Group lifted the debris from the trench and cleared the area around the site.peer-reviewe

LED-mellanbelysningsförsök i ett tomatblockväxthus i Pjelax, Närpes

Växthusnäringen i Finland är energiintensiv och stigande energikostnader äventyrar branschen. Tidigare undersökningar visar att växthusbranschen kräver stora mängder energi gällande både uppvärmning och konstbelysning samtidigt som stora andelar fossila bränslen fortfarande används. Elförbrukningen står idag för ungefär 60 % av den totala energiförbrukningen för åretrunttomatodlarna och den stora konsumtionen gör odlarna väldigt beroende av elbolagen och de varierande priserna på marknaden. I projektet Växthus-LED (1.12.2012–31.11.2014) har LED-mellanbelysningen Hortishine från företaget Netled Oy installerats som komplement till den traditionella HPS-toppbelysningen (högtrycksnatriumlampor) och testats i ett tomatblockväxthus i Pjelax, Närpes. LED-armaturerna installerades på arealen 484 m2 (HPS+LED) i ett blockväxthus med arealen 6300 m2. Som referens fungerade ett område i samma växthus med arealen 484 m2 (HPS). HPS-lampornas eleffekt vid referensområdet (HPS) sänktes för att motsvara elinstallationseffekten vid hybridområdet (HPS+LED). I den här rapporten presenteras hur LED-försöket har utförts, vilken mätutrustning och hurudant försöksväxthus som använts. Rapporten innehåller även analyser och resultat som berör t.ex. skördeförändring, energifördelning och -förbrukning och strålningsnivåer på olika ställen i försöksväxthuset. I rapporten finns även ett kapitel där olika PAR-mätare och LED-växtbelysningsarmaturer av olika tillverkare utvärderas. I slutet av rapporten diskuteras projektresultaten. Resultaten visade att skördeskillnaderna mellan HPS+LED (hybridområdet) och HPS (referensområdet) var positiva men små, totalt 2,2 % större skörd under hela odlingssäsongen vid HPS+LED. Största skördeskillnaden var under de mörkaste månaderna med +6,6 % vid HPS+LED. Elförbrukningen [kWh/kg tomat] var ca 5,1 % lägre vid HPS+LED jämfört med HPS under hela säsongen. Vid mätningar på konstljus i laboratorieförhållande konstaterades att skillnaden mellan olika PAR-mätare är stor. Vid mätning av olika LED-växtarmaturer visade det sig att PAR-effektiviteten varierar. Bästa LED-armaturen är ca 25 % effektivare än en HPS-lampa, om man jämför mellanbelysning med toppbelysning. Slutsatsen är att det krävs bättre LED-teknik innan LED blir ett verkligt konkurrenskraftigt alter-nativ, men LED-växtbelysning kan mycket väl vara den dominerande ljuskällan i växthus i framtiden. Frågan är om 2,2 % större skörd och 5,1 % lägre elförbrukning per producerat kilogram tomat idag är tillräckligt för att odlarna skall välja LED som mellanbelysning. Varje odlare är unik med unika växthus och det är många faktorer som man måste tänka på vid en investeringskalkyl.Kasvihuone-elinkeino Suomessa kuluttaa paljon energiaa ja nousevat energian hinnat vaikeuttavat alan kannattavuutta. Aikaisempien tutkimusten mukaan kasvihuonetuotanto käyttää suuria ener-giamääriä sekä lämmitykseen että tekovalotukseen. Suuri osa energiasta tuotetaan edelleen fossiilisilla polttoaineilla. Sähkönkulutus on tänä päivänä noin 60 % kokonaisenergiasta ympärivuotisella tomaattiviljelmällä. Suuri kulutusmäärä tekee viljelijän hyvin riippuvaiseksi sähköyhtiöistä ja vaihtelevista sähkön hinnoista. Kasvihuonehankkeessa ”Växthus-LED” (1.12.2012-31.11.2014) Netled Oy:n Hortishine LED-valaisimia asennettiin välivaloiksi HPS (suurpainenatrium) –valaisimien ylävalotuksen lisäksi tomaat-tihuoneeseen Närpiöön. LED-valaisimet asennettiin 484 m2:n alalle blokkihuoneeseen, jonka koko-naispinta-ala oli 6300 m2. Kontrollina ilman välivaloja oli samassa blokkihuoneessa samankokoinen koeala kuin LED valaisimilla. HPS-lamppujen sähkötehoa vähennettiin kontrollialueella vastaamaan koealan HPS+LED sähkötehoa. Tässä raportissa esitellään LED-kokeen suoritus, mittalaitteet ja niiden käyttö kasvihuoneessa. Raportissa on lisäksi analyysit ja tulokset, mm. sadon määrien erot, energian jakautuminen ja –kulutus sekä valaistusolosuhteita eri puolilla kasvihuonetta. Raportissa on lisäksi kappale, jossa eri PAR-valomittareita ja eri valmistajien LED-valaisimia verrataan. Lopussa tarkastellaan tuloksia. Satotulos oli 2,2 % suurempi HPS+LED-koejäsenessä kuin kontrollissa. Suurin satoero koejäsen-ten välillä oli pimeimpinä talvikuukausina, 6,6 % suurempi sato HPS+LED-koejäsenessä kuin kontrol-lissa. Koko viljelyjakson aikana sähkönkulutus kWh/kg tomaatteja oli noin 5,1 % alhaisempi HPS+LED kuin kontrollissa. Laboratorio-olosuhteissa tehdyt mittaukset osoittivat, että eri valmistajien PAR-valomittarit antoivat hyvin erilaisia lukemia. Eri valmistajien LED-valaisimissa oli eroja PAR-tehokkuuksissa. Paras LED-valaisin oli noin 25 % tehokkaampi kuin HPS. Loppupäätelmä oli, että LED-tekniikan on kehityttävä tehokkaammaksi, jotta se olisi varteenotettava kilpailija HPS:lle. Tulevaisuudessa LED-valot voivat hyvinkin olla pääasiallisin valon lähde kasvihuonevalaistuksessa. Viljelijän on mietittävä jos 2,2 % korkeampi sato ja 5,5 % alhaisempi sähkönkulutus tuotettua tomaattikiloa kohti tänäpäivänä ovat riittävästi, jotta välivaloksi valitaan LED. Jokaisella viljelijällä on kuitenkin erilaiset olosuhteet ja viljelystrategiat erilaisissa kasvihuoneissa, jotka vaikuttavat investointilaskemiin.201

Free diving-inspired breathing techniques for COPD patients:A pilot study

Objectives: Pulmonary rehabilitation (PR) is a key factor in enhancing self-management and exercise capacity in patients with chronic obstructive pulmonary disease (COPD). The content and length of PR varies between countries and authorities responsible for rehabilitation. After completion of rehabilitation, it is often difficult for patients to stay motivated and perform regular exercise. Methods: In this pilot study, nine patients with moderate to severe COPD completed a 6-week training programme consisting of free diving-inspired breathing techniques, designed to be incorporated into daily activities. Results: Participants significantly increased the distance walked in 6 min by 48 m (p < 0.05) and a significant reduction was seen on the COPD self-efficacy scale (p < 0.05). Furthermore, adherence to the programme sessions was very high at 96.3% and no adverse events occurred. Discussion: This pilot study tested the feasibility of introducing breathing techniques used by COPD patients to enhance their walking capacity. The techniques were well tolerated and participant’s adherence to the weekly group sessions was high

Can magnetotail reconnection produce the auroral intensities observed in the conjugate ionosphere?

[1] In a recent case study, Borg et al. (2007) reported that an inverted V structure, caused by a field-aligned potential drop of 30 kV producing very strong X-ray aurora, was found in connection with tail reconnection. However, the in situ particle measurements indicated clearly that the particles responsible for the X-ray aurora were not accelerated by the reconnection process. In this article, we report the predicted auroral intensities of thirteen reconnection events where Cluster passed through the reconnection region. For six of the events, global auroral imaging data were available and the predicted auroral intensities could be compared with the observed intensities. Our main findings are as follows: (1) Acceleration in the reconnection region is generally not sufficient to account for the observed auroral intensities. (2) Additional acceleration between the reconnection region and the ionosphere is needed to explain the auroral intensities. Although we see signatures that point toward potential drops at the flanks of bursty bulk flows (BBFs), we also find signatures of Alfvén wave accelerated electrons at 700 km and we are not able to determine the most likely acceleration mechanism. (3) The reconnection events are observed 2–14 min after substorm onset and indicate that reconnection is an expanding process observed along the poleward boundary of the aurora.publishedVersio

A synthetic data set to benchmark anti-money laundering methods

Bank transactions are highly confidential. As a result, there are no real public data sets that can be used to investigate and compare anti-money laundering (AML) methods in banks. This severely limits research on important AML problems such as efficiency, effectiveness, class imbalance, concept drift, and interpretability. To address the issue, we present SynthAML: a synthetic data set to benchmark statistical and machine learning methods for AML. The data set builds on real data from Spar Nord, a systemically important Danish bank, and contains 20,000 AML alerts and over 16 million transactions. Experimental results indicate that performance on SynthAML can be transferred to the real world. As use cases, we present and discuss open problems in the AML literature

The Influence of Curator Goals on Collections of Lived Experience Narratives: A Qualitative Study

Objective: The aim of this study was to investigate how curator goals influence the design of curation processes for collections of mental health lived experience narratives. The objectives were (1) to characterize the goals of a range of curators of existing collections, and (2) to identify specific working practices impacted by these goals.Research Design and Methods: Thirty semi-structured interviews were conducted with a purposive sample of curators of collections of lived experience narratives. Thematic analysis was conducted. Goals and impacts on working practice were tabulated, and narrative summaries were constructed to describe the relation between the two.Results: Curators interviewed were from seven countries (Brazil, Canada, Hong Kong, India, Italy, UK, USA), and 60% had lived experience of mental health service usage. Participants discussed eight goals that inspired their work: fighting stigma, campaigning for change in service provision, educating about mental health and recovery, supporting others in their recovery journey, critiquing psychiatry, influencing policy, marketing health services, and reframing mental illness. These goals influenced how decisions were made about inclusion of narratives, editing of narrative content, withdrawal rights, and anonymization. Conclusions: Our work will support the development of curatorship as a professional practice by shaping training for curators, helping curators reflect on the outcomes they would like to achieve, and helping individuals planning a collection to reflect on their motivations. We argue that transparency is an essential orientation for curators. Transparency allows narrators to make an informed choice about donating a narrative. It allows policy makers to understand the influences on a collection and hence treat it as a source of collective evidence