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Son yıllarda tarımsal üretimde yaşanan küresel dalgalanmalar mevcut tarım teknolojilerin sorgulanmasına neden olmuştur. Özellikle ülkemizde bitki besin elementi analizleri konusunda halihazırda analiz yöntemlerinin ağır maliyeti ve hammadde konusunda dışa bağımlılık üretici ve araştırmacılarımızın belini bükmektedir. Bu sorunların çözümü adına alternatif teknolojilerin geliştirilmesi amaçlanarak yaptığımız çalışmada günümüzde popüler olan X-ışını teknolojisinden yararlanılmış, bitkilerin toplam besin elementi içeriklerinin belirlenmesinde mevcut yöntemlere göre daha düşük maliyetle ve pratik bir şekilde yapılabileceği hedeflenmiştir. Bu doğrultuda, ülkemizde yaygın olarak yetiştiriciliği yapılan çay, lahana ve mısır bitkilerinin X ışını floresan tekniğiyle çalışan EDXRF cihazıyla kuru bitki okumaları yapılmış Kalsiyum (Ca), Potasyum (K), Magnezyum (Mg), Kükürt (S), Demir (Fe), Bakır (Cu), Çinko (Zn), Mangan (Mn), Fosfor (P) elementlerinin mg/kg cinsinden değerleri tespit edilmiştir. Eş zamanlı olarak bu bitki örnekleri ICP cihazında da okutulmuştur. ICP okumaları referans kabul edilerek EDXRF cihazı ICP-OES cihazına göre korelasyonu sağlanmıştır. Bu korelasyonda her element için lineer regresyon analizi yapılarak re-slope ve intercept değerleri belirlenmiştir. Her bir bitki için belirlenen bu değerler EDXRF cihazına yüklenerek elde edilen formül yardımıyla tahmini ICP değerleri hesaplanmıştır. Yapılan istatistiki hesaplamalar sonucunda r2 değerleri p<0.05 p<0.01 düzeyinde yakınlık tespit edilmiştir. Sistemin doğruluğunu kontrol etmek amacı ile sertifikalı referans bitki materyalleri kullanılmış, yapılan analizler sonucunda %81-119 arasında geri kazanımlar elde edilmiştir. Bu oranlar sertifikalı materyaller ile EDXRF cihazı arasındaki okumalarda pozitif ilişkiler görmemize sebep olmuştur. Böylelikle bu teknolojinin entegrasyonu bitki besin elementi analizleri için laboratuvar bağımlılığı ortadan kaldırarak, düşük maliyet ve zamandan tasarruf edilerek hem tarımsal yetiştiricilik açısından üretici ve araştırmacılar için önemli bir kaynak olma niteliği taşımaktadır. Global fluctuations in agricultural production in recent years has led to the questioning of existing agricultural technologies. Plant nutrient analyses on the cost and methods of analysis, especially in our country currently heavy dependence on raw materials manufacturer and bends the back of our researchers. For this purpose, in the work we do that are popular in recent years X-ray technology, taking advantage of a lower cost compared to the existing methods of the plants of total and elemental that can be done in a practical way, it is aimed. Our work in this direction, in our country, widely cultivated tea, cabbage, and corn plants, X-ray fluorescence EDXRF technique working with plant dry readings made with the device Calcium (Ca), potassium (K) magnesium (Mg), sulfur (S) Iron (Fe), Copper (Cu), zinc (Zn), Manganese (Mn), Phosphorus (P) of the elements mg/kg denominated in the values were determined. Simultaneously, the samples of this plant are given in the ICP device. The device adopted by reference readings EDXRF ICP ICP-OES according to the correlation device is provided. This correlation by linear regression analysis for each element in re-slope and intercept values were determined. The formula determined for each plant estimated values obtained by EDXRF-ICP values were calculated with the help of installing the device. Statistical calculations performed as a result of the r2 values p<0.05 p<0.01 at the level of proximity have been identified. Plant certified reference materials used to verify the accuracy of the system with the aim of your analysis results %81-119 between the feedback has been obtained. Positive relationships between these rates with certified materials EDXRF has been the reason we see the device in reading. Thus, the integration of this technology for plant nutrient analysis laboratory by eliminating the dependence, low cost and time saving in terms of agricultural production and producers and is intended to be an important resource for researchers. 44

The Master’s thesis analyzes energy consumption of WiFi modules, which serve to connect devices pertaining to the Internet of Things with the internet. In the context of the thesis, I have reviewed over 200 WiFi modules online and reduced the number of modules to 28 according to certain criteria outlined beforehand. Of the remaining 28 WiFi modules, I selected 4 that I have thoroughly examined and used for various measurements. For measurement purposes, I connected the modules with a test environment via an SPI interface and implemented the necessary software drivers on the microcontroller with ARM architecture. To measure energy consumption, I used a digital flow meter with a sampling frequency up to 20 kHz and an accuracy of the 300 μA order, for which I implemented a library in the Python programming language. I concentrated on the energy consumption using WPA2 encryption, since data security is always of utmost importance. The results of the measurements have shown that despite having comparable specifications, WiFi modules differ greatly between different manufacturers in terms of actual energy consumption. Additionally, the complexity of controlling WiFi modules also varies from manufacturer to manufacturer, which affects costs and development time. Magistrska naloga obravnava problematiko energijske porabe modulov WiFi, ki služijo za povezavo z internetom pri napravah interneta stvari. V sklopu naloge sem preko spleta pregledal preko 200 modulov WiFi, nato sem seznam po v naprej določenih grobih kriterijih skrčil na 28 modulov. Od preostalih 28 modulov WiFi sem izbral 4, ki sem jih nato temeljito preučil ter uporabil v meritvah. Za potrebe meritev sem module priklopil na testno okolje preko vmesnika SPI in implementiral potrebne programske gonilnike na mikro krmilniku z arhitekturo ARM. Za meritev porabe sem uporabil digitalni tokovni merilnik s frekvenco vzorčenja do 20 kHz in natančnostjo reda 300 μA, za katerega sem implementiral knjižnico v skriptnem jeziku python. Osredotočil sem se na porabo energije pri uporabi enkripcije WPA2, ker je varnost podatkov vedno zahtevana. Rezultati meritve so pokazali, da se kljub primerljivim specifikacijam porabe modulov WiFi med različnimi proizvajalci, dejanska poraba energije zelo razlikuje. Poleg tega pa se od proizvajalca do proizvajalca razlikuje tudi zapletenost krmiljenja modulov WiFi, kar vpliva na stroške in čas razvoja.

Environmental pollution as the result effluents discharged by industry is increasing, principally owing to mixtures of pollutants, including dyes. The objective of the present study was to evaluate the adsorption process of the bicomponent mixture of Tartrazine (Y5) and Brilliant Blue FCF (B1) dyes in a dynamic regime (fixed-bed column), using rice husks (RH) as adsorbent material. A 3-level response surface design of experiments was employed to evaluate the adsorption process of the dyes in the mixture at the following initial concentrations: 0.0216, 0.0739, 0.1261, 0.1477 (mmol L−1). The response surface analysis of the experimental design made it possible to identify a competitive adsorption of both dyes. RH had higher affinity for B1, although the adsorption capacity changed depending on the concentration of each dye in the mixture. The highest RH adsorption capacity was 3.4 mg g−1 for B1 and 1.45 mg g−1 for Y5, respectively, under a monocomponent condition. It was considered that the interactions in the mechanism proposed for the adsorption process occurred because of the formation of hydrogen bonds between the sulfonate groups of the dyes and the –OH groups present on the surface of the adsorbent. B1 had a higher affinity towards RH because it had one more sulfonate group than Y5. The multiple-response optimization results make it possible to recommend the use of RH beds with low concentrations of B1 and Y5 in the same feed.

Salt marsh vegetation density varies considerably on short spatial scales, complicating attempts to evaluate plant characteristics using airborne remote sensing approaches. In this study, we used a mast-mounted hyperspectral imaging system to obtain cm-scale imagery of a salt marsh chronosequence on Hog Island, VA, where the morphology and biomass of the dominant plant species, Spartina alterniflora, varies widely. The high-resolution hyperspectral imagery allowed the detailed delineation of variations in above-ground biomass, which we retrieved from the imagery using the PROSAIL radiative transfer model. The retrieved biomass estimates correlated well with contemporaneously collected in situ biomass ground truth data ( R 2 = 0.73 ). In this study, we also rescaled our hyperspectral imagery and retrieved PROSAIL salt marsh biomass to determine the applicability of the method across spatial scales. Histograms of retrieved biomass changed considerably in characteristic marsh regions as the spatial scale of the imagery was progressively degraded. This rescaling revealed a loss of spatial detail and a shift in the mean retrieved biomass. This shift is indicative of the loss of accuracy that may occur when scaling up through a simple averaging approach that does not account for the detail found in the landscape at the natural scale of variation of the salt marsh system. This illustrated the importance of developing methodologies to appropriately scale results from very fine scale resolution up to the more coarse-scale resolutions commonly obtained in airborne and satellite remote sensing.

Darfur farming and pastoralist livelihoods are both adaptations to the environmental variability that characterises the region. This article describes this adaptation and the longer‐term transformation of these specialised livelihoods from the perspective of local communities. Over several decades farmers and herders have experienced a continuous stream of climate, conflict and other shocks, which, combined with wider processes of change, have transformed livelihoods and undermined livelihood institutions. Their well‐rehearsed specialist strategies are now combined with new strategies to cope. These responses help people get by in the short term but risk antagonising not only their specialist strategies but also those of others. A combination of factors has undermined the former integration between farming and pastoralism and their livelihood institutions. Efforts to build resilience in similar contexts must take a long‐term view of livelihood adaptation as a specialisation, and consider the implications of new strategies for the continuity and integration of livelihood specialisations.

The greenhouse gas (GHG) emissions, expressed in carbon dioxide equivalents (CO2-eq), of different Austrian biogas systems were analyzed and evaluated using life-cycle assessment (LCA) as part of a national project. Six commercial biogas plants were investigated and the analysis included the complete process chain: viz., the production and collection of substrates, the fermentation of the substrates in the biogas plant, the upgrading of biogas to biomethane (if applicable) and the use of the biogas or biomethane for heat and electricity or as transportation fuel. Furthermore, the LCA included the GHG emissions of construction, operation and dismantling of the major components involved in the process chain, as well as the use of by-products (e.g. fermentation residues used as fertilizers). All of the biogas systems reduced GHG emissions (in CO2-eq) compared with fossil reference systems. The potential for GHG reduction of the individual biogas systems varied between 60% and 100%. Type of feedstock and its reference use, agricultural practices, coverage of storage tanks for fermentation residues, methane leakage at the combined heat and power plant unit and the proportion of energy used as heat were identified as key factors influencing the GHG emissions of anaerobic digestion processes.

Abstract In this study, intergeneric grafting was employed between Populus cathayana and Salix rehderiana to investigate the grafting compatibility of the two Salicaceae plants and to reveal whether grafting can improve their drought resistance. Under different grafting combinations (P. cathayana scion with P. cathayana rootstock, P/P; P. cathayana scion with S. rehderiana rootstock, P/S; S. rehderiana scion with S. rehderiana rootstock, S/S; and S. rehderiana scion with P. cathayana rootstock, S/P), the survival and growth rate, biomass accumulation and allocation, photosynthetic traits, carbon isotope composition (δ13C), relative water content (RWC) and non-structural carbohydrates (NSCs) were measured. The results showed that the grafting compatibility between P. cathayana and S. rehderiana was very high, as the survival rates ranged from 76% to 100% under different grafting combinations. Drought significantly decreased growth, biomass accumulation, photosynthetic pigment contents, net photosynthesis rates (Pn) and RWC, and increased δ13C in all grafting combinations. Under drought stress, biomass accumulation, total chlorophyll, transpiration rate (E) and Pn were higher in P/P and P/S than in S/S and S/P. Compared with P/P, the growth rate, biomass accumulation, root/aboveground ratio (R/A ratio), carotenoid, RWC, starch and total soluble sugar (TSS) of P/S were less affected by drought. The height growth rate (GRH), R/A ratio, carotenoid, chlorophyll a, total chlorophyll, WUEi and TSS of S/P were lower than those of S/S under water-limited conditions. Moreover, a principal component analysis indicated that P/S and S/S had higher drought resistance than P/P and S/P under water deficits. The used method allows combining specific advantageous traits from P. cathayana and S. rehderiana, which may be a highly useful tool to enhance drought resistance in the cultivation of Salicaceae plants.