Time-to-provision evaluation of IoT devices using automated zero-touch provisioning

The Internet of Things (IoT) is being widely adopted in today's society, interconnecting smart embedded devices that are being deployed for indoor and outdoor environments, such as homes, factories and hospitals. Along with the growth in the development and implementation of these IoT devices, their simple and rapid deployment, initial configuration and out-of-the-box operational provisioning are becoming prominent challenges to be circumvented. Considering a large number of heterogeneous devices to be deployed within next generation IoT networks, the amount of time needed for manual provisioning of these IoT devices can significantly delay the deployment and manual provisioning may introduce human-induced failures and errors. By incorporating zero-touch provisioning (ZTP), multiple heterogeneous devices can be provisioned with less effort and without human intervention. In this paper, we propose software-enabled access point (Soft-AP)- and Bluetooth-based ZTP solutions relying only on a single mediator device and evaluate their performances usi ng LOG-A-TEC testbed against manual provisioning in terms of the time required for provisioning (time-to-provision, TTP). We demonstrate that on average, Soft-AP- and Bluetooth-based ZTP solutions outperform manual provisioning with about 154% and 313% when compared to the expert provisioning, and with about 434% and 880% when compared to the non-expert provisioning in terms of TTP performances, respectively

Утицај секторијалне резидбе на продуктивност, вегетативни раст и квалитет плода сорте боровнице „Duke“ (Vaccinium corymbosum L.) гајене у супстрату

Рад приказује резултате компаративног испитивања утицаја секторијалне (СР) и конвенционалне резидбе (КР) биљака високожбунасте боровнице на параметре генеративног и вегетативног потенцијала, као и физичке и хемијске особине плода. СР, као нова стратегија резидбе боровнице која се примењује у Чилеу, подразумева да се сваке године уклони само 1/4 од укупног броја базалних грана у жбуну, без уклањања и скраћивања грана у осталим секторима жбуна, што може допринети: 1) олакшаном и бржем извођењу резидбе; 2) смањењу утрошка радне снаге; 3) побољшању осветљености у централном делу жбуна; 4) повећању приноса. Испитивања су вршена у периоду од 2019. до 2021. године у комерцијалном засаду боровнице, који се налази у месту Гружа (општина Кнић). Засад је подигнут у пролеће 2017. године садњом двогодишњих биљака сорте "Duke" у саксије запремине 113 l, које су испуњене супстратном смешом састављеном од струготине четинара и белог тресета (однос 50:50). Саксије су постављене на растојању од 0,8м у реду и 3,0м између редова (4170 биљака/ha). Добијени резултати су показали да је у третману са СР регистрован значајно нижи број плодова (1.233) и принос по жбуну (2,16 kg/жбуну), који се повећавао током година испитивања, достижући највишу вредност од 3,06 kg у 2021. години. Значајно повећање у вегетативном расту је забележено само код пречника базалних грана у третману са КР, док се висина и ширина жбуна нису значајно разликовале у зависности од примењеног начина резидбе. КР је испољила позитиван утицај на масу, димензије плода, број семенки у плоду и садржај укупних шећера, са доминантним учешћем фруктозе и глукозе (40,3 и 37,6 g/kg FW по редоследу), док је у третману са СР забележено значајно повећање садржаја укупних киселина (17,08 g/kg FW са највећим уделом лимунске и квинске киселине (7,14 и 9,17 g/kg FW по редоследу). Садржај укупних антоцијана, деривата хидроксициметних киселина, укупних флавонола и флаванола је био значајно већи у плодовима убраним у третману са СР

HOW DOES SECTORIAL PRUNING AFFECT THE VEGETATIVE GROWTH, PRODUCTIVITY AND FRUIT QUALITY OF SUBSTRATE-GROWN HIGHBUSH BLUEBERRY CV. 'BLUECROP'?

The impact of pruning techniques on the plant growth, yield components and fruit quality traits of substrate-grown highbush blueberry (Vaccinium corymbosum) cultivar 'Bluecrop' were evaluated over four years (2019-2022). The orchard was planted in the village of Gruža (Knić municipality, Serbia) in the spring of 2017 with 5-year-old nursery plants using 113 l polypropylene pots spaced 0.8 m apart in a row and 3.0 m between rows (4,170 plants/ha). At the onset of the trial the ‘Bluecrop’ plants were 8 years old. The two pruning techniques were applied: i) conventional pruning (CP) - removal of the most unproductive canes at the center of the canopy, and weak and excessively fruiting shoots from the top of bushes, and ii) sectorial pruning (SP) - only removal of basal canes in ¼ of the canopy each year. The average number of basal canes per bush was significantly lower in SP than in the CP treatment (14.4 vs. 17.4 canes bush-1 , respectively). SP plants had thinner canes than CP plants, which increased over the years of the study and reached a maximum diameter of 11.12 mm in 2022. CP had a positive influence on fruit yield (5.98 kg bush-1 ), which was associated with a 20% higher number of fruits per bush than in sectorial pruned plants. The fruit yield increased in the first three years of the study, reaching a maximum value in 2021 (7.57 kg per bush), whereas an opposite trend was observed in average fruit weight over the years, with the lowest value reached in the last harvest year (1.81 g). Fruit weight and soluble solids content were not affected by the pruning method, while the content of total acids, total anthocyanins and total phenolics were significantly higher in fruit harvested from the SP treatment (0.70%, 37.04 mg eq mvd-3-G /100 g FW and 1.18 mg eq GA/g FW, respectively) along with the total antioxidant capacity (8.39 mg eq AsA /g FW)

A Genome Wide Association Study of arabinoxylan content in 2-row spring barley grain

In barley endosperm arabinoxylan (AX) is the second most abundant cell wall polysaccharide and in wheat it is the most abundant polysaccharide in the starchy endosperm walls of the grain. AX is one of the main contributors to grain dietary fibre content providing several health benefits including cholesterol and glucose lowering effects, and antioxidant activities. Due to its complex structural features, AX might also affect the downstream applications of barley grain in malting and brewing. Using a high pressure liquid chromatography (HPLC) method we quantified AX amounts in mature grain in 128 spring 2-row barley accessions. Amounts ranged from ~ 5.2 μg/g to ~ 9 μg/g. We used this data for a Genome Wide Association Study (GWAS) that revealed three significant quantitative trait loci (QTL) associated with grain AX levels which passed a false discovery threshold (FDR) and are located on two of the seven barley chromosomes. Regions underlying the QTLs were scanned for genes likely to be involved in AX biosynthesis or turnover, and strong candidates, including glycosyltransferases from the GT43 and GT61 families and glycoside hydrolases from the GH10 family, were identified. Phylogenetic trees of selected gene families were built based on protein translations and were used to examine the relationship of the barley candidate genes to those in other species. Our data reaffirms the roles of existing genes thought to contribute to AX content, and identifies novel QTL (and candidate genes associated with them) potentially influencing the AX content of barley grain. One potential outcome of this work is the deployment of highly associated single nucleotide polymorphisms markers in breeding programs to guide the modification of AX abundance in barley grain

Productivity and fruit quality of 'Clery' strawberry affected by planting density in a soilless growing system

This study illustrates the differences in yield components, morphometric and nutritional fruit properties of the strawberry cultivar 'Clery' affected by planting density in a soilless growing system. Cold stored frigo plants were planted at the beginning of August 2018 in bags filled with 20 L substrate mixture which were placed within styrofoam containers on a 1.2 m high tabletop. The effect of two planting densities, 10 and 14 plants m(-2), on mentioned parameters was monitored during 2019 in a greenhouse from the 'Euro Fruit' company in Kupinovo, Serbia. Results showed that the harvest window was similar in both applied planting densities and it lasted around one month (from April 20 to May 20, 2019). Contrary to this, a significantly higher number of fruits plant(-1), yield plant(-1) and average fruit weight was registered in the density of 10 plants m(-2) (27.8; 545.4 g plant(-1); 20.0 g, respectively). Higher planting density of 14 plants m(-2) significantly increased concentrations of glucose, citric, malic and shikimic acids in the fruit (20.3 g kg(-1); 5.41 mg g(-1); 2.23 mg g(-1) and 20.13 mu g g(-1), respectively). Soluble solids, fructose and vitamin C content in fruit were not affected by the planting density. These results indicate that the use of a planting density of 10 plants m(-2) could be considered more suitable in a soilless production system of 'Clery' with optimal yields plant(-1) and m(-2) despite positive effects on some morphometric and chemical fruit traits at the density of 14 plants m(-2)