Development of a custom-built RTK-GNSS positioning system for agricultural operations

Received: February 1st, 2023 ; Accepted: June 16th, 2023 ; Published: July 6th, 2023 ; Correspondence: [email protected] objective of this research is to assess positioning accuracy of a custom-built RTK (Real Time Kinematic) base station. Setting up a RTK base station with open-source tools is rather straightforward process requiring only few components and basic programming skills. The base station and receiver unit were developed by using a SparkFun GPS-RTK2 Board with U-Blox ZED-F9P module. The board was paired with U-blox Multi band GNSS (Global Navigation Satellite System) antenna. The board can use GNSS satellite signals from Galileo, BeiDou, Glonass and GPS systems. The positioning accuracy was evaluated in a fixed position and during operations in agricultural fields. The RTK correction signal was used in connection with soil scanning measurements in different crop fields of the Viikki Research Farm of the University of Helsinki. For accuracy assessment, comparative measurements were carried out with a commercial network RTK (NRTK) correction signal. The vertical and horizontal accuracy of the positioning signal were evaluated based on the accuracy variables calculated by the receiver. The vertical accuracy was also evaluated by mapping the scanned trajectories on the height map which was obtained from NSL (National Land Survey of Finland) open map data service. The custom-built RTK positioning system accuracy was considered generally precise enough for autonomous field work, but the reliability of the observed accuracy should be confirmed with more extensive measurements. The commercial NRTK signal accuracy was considered very good and reliable also for the vertical direction

Ludics and its Applications to natural Language Semantics

Proofs, in Ludics, have an interpretation provided by their counter-proofs, that is the objects they interact with. We follow the same idea by proposing that sentence meanings are given by the counter-meanings they are opposed to in a dialectical interaction. The conception is at the intersection of a proof-theoretic and a game-theoretic accounts of semantics, but it enlarges them by allowing to deal with possibly infinite processes

Fullereenittomat push-pull-tyyppiset akseptorimateriaalit BHJ-aurinkokennoissa

Tiivistelmä. Orgaanisten aurinkokennojen noin kolmenkymmenen vuoden taival on nähnyt suurta kehitystä ensimmäisten kennojen 1 % hyötysuhteista päätyen lopulta jopa yli 12 % yltäviin hyötysuhteisiin. Hyötysuhdetutkimus painottui pitkän aikaa lähinnä donoripolymeerien optimointiin käyttäen PCBM-fullereenia eräänlaisena standardiakseptorina sen hyvien varauksenkuljetusominaisuuksiensa takia. Näyttäisi kuitenkin siltä, että fullereeni on pitkälti saavuttanut huippunsa orgaanisten aurinkokennojen kehitystaivalen varrella ja tutkimussuunta on alkanut kääntyä kohti vaihtoehtoisia akseptorimateriaaleja. Fullereenin ongelmina ovat sen tuotantoprosessista johtuva kallis hinta, stabiilisuusongelmat ja toisaalta myös huonosti säädettävissä olevat absorptio-ominaisuudet vaihtoehtoisiin materiaaleihin verrattuna. Polymeeriakseptorien ohella yhtenä vaihtoehtona fullereenille on alettu tutkia pienimolekyylisiä akseptoreita niiden helpon muokattavuuden ja polymeereihin verrattuna tasalaatuisen tuotantoprosessin takia. Tämän kirjallisuustutkielman painopisteenä toimivat push-pull-tyyppiset pienmolekyyliakseptorit niiden erittäin lupaavaksi osoittautuneen kehityssuunnan takia. Esimerkiksi ITIC-niminen molekyyli on tuottanut hyvää tulosta ja C71-fullereenia hipovan hyötysuhteen heti kättelyssä. Lisäksi kyseinen materiaali inspiroi muita vastaavanlaisia akseptoreita ja tämän tutkielman kirjoittamisen aikana fullereenittomilla akseptoreilla saavutetut hyötysuhteet ovat nousseet jopa 18 %:iin huolellisen molekyylisuunnittelun ja aktiivikerroksen hienorakennevuorovaikutusten optimoinnin tuloksena. Vaikka painopiste tutkielmassa on lähinnä korkeiden hyötysuhteiden tavoittelussa, on huomiota kiinnitetty myös erilaisiin prosessointimenetelmiin ja niissä käytettyihin liuottimiin ja lisäaineisiin, jotka luovat omanlaisiaan haasteita edettäessä kohti kennojen kaupallistamista ja laajamittaisempaa teollista tuotantoa

Game theoretical semantics for some non-classical logics

Paraconsistent logics are the formal systems in which absurdities do not trivialise the logic. In this paper, we give Hintikka-style game theoretical semantics for a variety of paraconsistent and non-classical logics. For this purpose, we consider Priest’s Logic of Paradox, Dunn’s First-Degree Entailment, Routleys’ Relevant Logics, McCall’s Connexive Logic and Belnap’s four-valued logic. We also present a game theoretical characterisation of a translation between Logic of Paradox/Kleene’s K3 and S5. We underline how non-classical logics require different verification games and prove the correctness theorems of their respective game theoretical semantics. This allows us to observe that paraconsistent logics break the classical bidirectional connection between winning strategies and truth values

ALS patients in otorhinolaryngology : A retrospective study

Objectives Given its rarity and the lack of clear clinical markers, amyotrophic lateral sclerosis (ALS) remains a diagnostic challenge. Because bulbar-onset ALS (buALS) presents with impaired speech or swallowing, patients are often primarily referred to an otolaryngologist (ORL) or phoniatrician. The objectives of this retrospective cohort study were to analyze the role of ORLs and phoniatricians in ALS diagnostics and treatment and the potential diagnostic delay related to initial visit to aforementioned specialists. Methods We reviewed data for all 327 patients treated for ALS through the Hospital District of Helsinki and Uusimaa (HUS) between 2010 and 2014, focusing specifically on 110 (34%) patients presenting with bulbar nerve onset (buALS). Their presenting symptoms, referral to specialized care, and delay in referral to a neurology clinic were assessed. Indications and findings from swallowing studies were reviewed as well as the incidence of percutaneous endoscopic gastrostomy (PEG) and tracheostomy. Results Among the 110 patients with buALS, 64 (58%) were primarily referred to a neurologist, 28 (25%) to an ORL, and five (5%) to a phoniatrician. The most common presenting symptom was dysarthria in 89 patients, (81%), followed by dysphagia in 26 (24%). In most cases, an ORL or phoniatrician suspected a neuromuscular disease; however, in eight (24%) cases, the neurological etiology of symptoms was missed. Overall, 49 (45%) patients underwent a swallowing study and 86 (78%) patients underwent PEG placement. Conclusions Among buALS patients, 30% initially consulted an ORL or phoniatrician and 45% underwent a swallowing study. Based on our results, swallowing studies rarely lead to immediate PEG placement. An initial visit to other specialists had no impact on diagnostic delays or survival.Peer reviewe

Work-up of globus : assessing the benefits of neck ultrasound and videofluorography

Globus patients with normal ear, nose, and throat ( ENT) status are a diagnostic challenge. The symptom may be long lasting and cause concern about malignancy, leading to possibly unnecessary further investigation. The aim of the study was to assess whether radiological examinations are useful in globus diagnostics, how often patients suffer from persistent globus, and whether globus patients with normal ENT status develop a malignancy during a follow-up. We reviewed medical records of all 76 globus patients referred to Helsinki University Hospital, Department of Otorhinolaryngology-Head and Neck Surgery in 2009. Patient history and findings in physical and radiological examinations were registered. A questionnaire concerning patients' present pharyngeal symptoms was sent 3 and 6 years after their initial visit. Data from the Finnish Cancer Registry revealed whether patients developed malignancies within a 3-year follow-up. Based on medical records, neck ultrasound was performed for 37 (49 %) and videofluorography for 22 patients (29 %), with nonsignificant findings. After a 3- and 6-year follow-up, half patients indicated that they were asymptomatic or had fewer symptoms, whereas the rest had persistent symptoms. The Finnish Cancer Registry data confirmed that globus patients developed no head and neck malignancies during a 3-year follow-up. In the present study, neck ultrasound and videofluorography showed no additional benefit to evaluate the globus etiology in patients whose ENT status was normal. Half the globus patients suffered from persistent symptoms after a 3- and 6-year follow-up, indicating that globus may cause discomfort chronically. However, no patients developed malignancies during a 3-year follow-up.Peer reviewe

The Intrinsic Quantum Nature of Nash Equilibrium Mixtures

Every undergraduate textbook in game theory has a chapter discussing the difficulty to interpret the mixed Nash equilibrium strategies. Unlike the usual suggested interpretations made in those textbooks, here we prove that these randomised strategies neither imply that players use some coin flips to make their decisions, nor that the mixtures represent the uncertainty of each player about the others' actions.Instead, the paper demonstrates a fundamental connection between the Nash equilibrium 'randomised' or 'mixed' strategies of classical game theory and the pure quantum states of quantum theory in physics. This link has some key consequences for the meaning of randomised strategies:In the main theorem, I prove that in every mixed Nash equilibrium, each player state of knowledge about his/her own future rational choices is represented by a pure quantum state. This indicates that prior making his/her actual choice, each player must be in a quantum superposition over her/his possible rational choices (in the support of his probability measure). This result notably permits to show that the famous 'indifference condition' that must be satisfied by each player in an equilibrium is actually the condition that ensures each player is in a 'rational epistemic state of ignorance' about her/his own future choice of an action

Readout system test benches

We propose to develop and exploit versatile multi-purpose Personal Computer-based Test Benches to support the evaluation and design of the basic elements required for digital front-end readout and data transmission systems for an LHC experiment. These test benches will have modular hardware facilities for the operation of new readout system components under realistic conditions, and will implement advanced modern software engineering concepts. They will support components such as fast ADCs, hybrid fibre-optic transceivers, and the prototype VLSI systolic array and data-flow processors currently being developed in national research laboratories and by the emerging European HDTV industry. These efforts would also lay the foundations for projects involving the development of custom-designed VLSI circuits