Mehanizovana berba peršuna u regionu Južnog Banata

So far, many types, styles and sizes of mowing equipment has been developed and introduced in the agricultural practice. Therefore, leaf crops harvesting seems to be easier to mechanize with respect to other cultivars. However, keeping the leaf matter clean and loaded into a dryer without contaminants limits the kind of mechanization that can be used. In this paper is given a general review of Parsley (Petroselinum crispum) crops properties, possible benefits of its applications and basic principles of mechanized growing technology. In addition a simplified agroeconomical calculation of the production costs against possible income from sold vegetables, based on current prices expressed in euros is also provided. This way, the production of Parsley herbs is justified from medical, nutritive, culinary and economical points of view. Finally, results of testing three harvesters of different design, applied for collecting and preparation of parsley leaves at parcels in the region of south Banat (North Serbia) are presented and analysed. Measurements comprehended following working parameters: harvester velocity, loss of acquired crop and cutting lengths distribution of parsley leafs.Do sada je razvijen i uveden u poljoprivrednu proizvodnju veliki broj tipova i konstrukcija mašina za košenje. Stoga se čini da je mehanizovanje žetve lisnatih useva lakše u poređenju sa ostalim kulturama. Ipak, očuvanje čistoće lisnatih useva i njihov utovar u sušare bez neželjenih kontaminanata ograničava vrstu opreme koja se može koristiti. U radu je prikazan opšti pregled opreme i postupaka za mehanizovano ubiranje peršuna (Petroselinum crispum). Na osnovu uprošćene ekonomske analize, zasnovane na tekućim cenama u Srbiji izraženim u evrima, potvrđena je opravdanost uzgoja ove poljoprivredne kulture sa ekonomske tačke gledišta. Konačno, prikazani su i analizirani rezultati uporednog testiranja tri kombajna različite konstrukcije, primenjene za sakupljanje i pripremu lišća peršuna na parcelama u regionu južnog Banata (severna Srbija). Merenjem su obuhvaćeni: brzina kombajna, gubici sakupljenog useva i raspodela dužina isečenih frakcija peršuna

Civic Networks of the Srem District – Overcoming or Indicating the Digital Divide?

The phenomenon of digital divide has been examined recent years from many different viewpoints. There is still a variety of definitions and a range of propositions for its examination and measuring. According to the OECD reports: “digital divide refers to the gap between individuals, households, business and geographic areas at different socio-economic levels with regard both to their opportunities to access information and communication technologies and to their use of the Internet for a wide variety of activities”. Civic networks are regarded as one of such activities, where the Internet has been used to reflect civic life of the particular region. Measuring the digital divide is mainly based on comparative statistics, primarily in an international context. In this paper, results of qualitative observations of the civic networks are considered as a possible indicator of the digital divide overcome in a regional context

Kritički prikaz akcionog plana adaptacije Beograda na klimatske promene

In the European context, the region of the Western Balkans is seen as one significantly affected by the actual climate changes. Using experiences from numerous European cities that are already adapting to their changing climates, the capital cities of the Western Balkans countries are starting to develop strategies of adaptation to actual and expected climate conditions. In this article we give an overview of the document titled Climate Change Adaptation Action Plan with Vulnerability Assessment issued by the City of Belgrade, Secretariat for Environmental Protection. After giving a brief introduction on the document creation within the project Climate Change Adaptation in the Western Balkans and the methodology applied, a structure of the document has been presented highlighting proposed adaptation actions. The paper continues with a critique of the document, main point of which is a lack of indication of financial sources for the proposed actions, as well as interlinking with national adaptation strategies and disaster risk reduction for the parts of the city particularly affected with the floods in 2014.U evropskom kontekstu, područje Zapadnog Balkana smatra se jednim od najviše pogođenih aktuelnim klimatskim promenama. Koristeći iskustva brojnih evropskih gradova koji su usvojili mere adaptacije na izmenjene klimatske uslove, glavni gradovi zemalja Zapadnog Balkana započinju kreiranje strategija prilagođavanja na postojeće i očekivane klimatske promene. U ovom radu dat je kritički osvrt na dokument pod naslovom Akcioni plan adaptacije na klimatske promene sa procenom ranjivosti koji je publikovao Sekretarijat za zaštitu životne sredine Grada Beograda. Nakon kratkog osvrta na nastanak ovog dokumenta u okviru projekta Adaptacija na klimatske promene u zemljama Zapadnog Balkana, kao i na primenjenu metodologiju, prikazana je struktura celokupnog dokumenta sa akcentom na predložene mere adaptacije. Rad se nastavlja kritikom prikazanog dokumenta, čija je ključna tačka odsustvo indikacije o finansijskim aspektima podrške predloženim merama adaptacije, kao i povezivanje/formiranje nacionalne strategije adaptacije na klimatske promene i dokumenata o redukciji rizika od prirodnih katastrofa za delove grada koji su naročito bili ugroženi u poplavama 2014

Comparison and evaluation of recently reported methods for optimization of industrial drying regimes

In our previous studies we have presented the calculation method along with the procedure for setting up the non isothermal drying regime. Even though this method is harmonized, with the theory of moisture migration during drying and can be used to predict the optimal industrial drying regime and proper drying air parameters, up till now it was not compared with other models. The main goal of this paper, was to compare and evaluate our model with the one reported by the German group of authors in 2008. The first task was to create criteria for model evaluation. Five parameters were chosen: non-existence of cracks, total drying time, twist coefficient, chamber coefficient and flexural strength. The second task was to create a software tool, for modeling the first and second drying section of green clay masonry element, using the instructions provided within the published articles. The third task was to apply German and our procedure on the same clay raw material. Results have shown the absence of cracks on dried and fired samples. In the case of German method total drying time, as well as twist and camber coefficients were higher while the physico - mechanical properties were lower. Presented results have additionally validated that our dying model can be used for the accurate prediction of industrial drying kinetics and a reliable estimation of moisture transport during drying

Defining a procedure for predicting the duration of the approximately isothermal segments within the proposed drying regime as a function of the drying air parameters

One of the main disadvantages of the recently reported method, for setting up the drying regime based on the theory of moisture migration during drying, lies in a fact that it is based on a large number of isothermal experiments. In addition each isothermal experiment requires the use of different drying air parameters. The main goal of this paper was to find a way how to reduce the number of isothermal experiments without affecting the quality of the previously proposed calculation method. The first task was to define the lower and upper inputs as well as the output of the "black box" which will be used in the Box-Wilkinson's orthogonal multi-factorial experimental design. Three inputs (drying air temperature, humidity and velocity) were used within the experimental design. The output parameter of the model represents the time interval between any two chosen characteristic points presented on the Deff -t. The second task was to calculate the output parameter for each planed experiments. The final output of the model is the equation which can predict the time interval between any two chosen characteristic points as a function of the drying air parameters. This equation is valid for any value of the drying air parameters which are within the defined area designated with lower and upper limiting values

Non isothermal drying process optimisation - Drying of clay tiles

In our previous studies we have developed a model for determination of the variable effective diffusivity and identification of the exact transition points between possible drying mechanisms. The next goal was to develop a drying regime which could in advance characterize the real non isothermal process of drying clay tiles. In order to do this four isothermal experiments were recorded. Temperature and humidity were maintained at 350C / 75%; 450C / 70%; 450C / 60% and 500C / 60%; respectively in each experiment. All experimentally collected data were analyzed and the exact transition points between possible drying mechanisms were detected. Characteristic drying period (time) for each isothermal drying mechanism was also detected. The real, non-isothermal drying process was approximated by 5 segments. In each of these segments approximately isothermal drying condition were maintained. Temperature and humidity of the drying air, in the first four segments, was maintained on the same level as in recorded isothermal experiments while in the fifth segment, it were maintained at 700C / 40%. The duration of the first four segments were calculated from the diagrams Deff - t respectively for each experiment. The clay tile in experiment five was dried without cracking using the proposed non isothermal drying regime

Nutricioni i hormonalni faktori rastenja kalusnog tkiva graška

A callus tissue was obtained from an immature embryo of Meteor pea (Pisum sativum cv. Meteor) and its requirements for optimal growth were investigated. The tissue showed rather peculiar responses in respect to the concentration of mineral salts, to the carbohydrate used and to the kind of auxin supplied to the medium. Of the five mineral solutions tested, only two could support growth, in which the concentration of mineral salts was relatively high. It was not possible to show the specific role for any particular element. However, the stimulating effect of any ion was not evident, unless the content of potassium was increased at the same time. Sucrose was the best carbon source, while the tissue could not grow on media containing glucose or fructose. The addition of thiamine was necessary, while nicotinic acid had a beneficial effect. An absolute requirement for auxin was shown. Only the synthetic auxins could stimulate growth of the tissue, while IAA was almost ineffective. Cytokinins and gibberellic acid were not needed, but they considerably increased the weight of the tissue.Kalusna kultura tkiva graška (Pisum sativum L. cv. Meteor) dobijena je od nezrelog embriona i ispitivani su faktori neophodni za njeno optimalno rastenje. Od pet mineralnih rastvora samo dva, koji imaju relativno visoku koncentraciju mineralnih soli, mogu da stimuliraju rastenje. Nijedan elemenat posebno nema u tome specifičnu ulogu. Međutim, stimulativni efekat bilo kog jona opaža se samo ako je u isto vreme i koncentracija kalij uma povećana. Najbolji izvor ugljenika je saharoza, dok na rastvorima sa glukozom ili fruktozom tkiva ne mogu da rastu. Vitamin Bt je neophodan za rastenje, dok nikotinska kiselina ima povoljan efekat. Takođe je pokazano da je neophodno dodavati auksin. Međutim, samo sintetički auksini mogu da indukuju rastenje, a IAA je skoro sasvim neaktivna. Citokinini i giberelini nisu neophodni, ali znatno povećavaju težinu tkiva

A Model of Security Management System for Transportation Systems

The Transportation Systems Sector, a sector that comprises all modes of transportation (aviation, maritime, mass transit, highway, freight rail, and pipeline), is a vast, open, interdependent networked system that moves millions of passengers and millions of tons of goods. The transportation network is critical to both our way of life and economic vitality. Ensuring its security is a mission charged to all sector partners, including governments (national, regional, local) and private industry stake-holders. Transportation systems represent an important part of critical infrastructure. The security and safety of transportation influence all other social and industrial pro-cesses. Disruption of this system causes disruptions in all other segments of social life. Specific characteristics of this system which influence its security are: easy accessibility, interconnection and vastness. Hence, the tolerance of this system to malfunctions and security and safety risks is very low. In order to achieve security and safety, along with reliability, efficiency and punctuality of these systems we need to consider applying an 40integrated approach to security and safety management systems. Like many other criti-cal infrastructure sectors, the Transportation Systems Sector faces a dynamic landscape of potential natural disasters, accidents, and terrorist attacks. The terrorist threat poses special challenges. Taken together, the risk from terrorism and other hazards demands a coordinated approach involving all sector stakeholders. Stakeholders throughout the sector have been and continue to be actively developing methods to improve their oper-ational security and overall resilience. However, since the Transportation Systems Sec-tor is segmented by individual modes, an increased emphasis is needed on a risk-based approach across the entire transportation spectrum. Security management systems, by integrating security awareness throughout the organization and verifying compliance through quality assurance, can be a significant force in achieving the highest possible level of regulatory compliance. Specific security practices, training and audit functions within a security management system should all be built so as to ensure compliance with applicable national transportation security programs. As an attempt to deal with these problems, this paper presents an integrated approach to safety and security and a model of safety and security management system for transportation organizations

Characterization of drying behavior and modeling of industrial drying process

The general method for industrial chamber dryer optimization was reported in this paper. The first step in finding the most suitable drying regime is to characterized the clay raw material, especially its water loss at 2000C and to determine the critical drying rate inside the specially constructed laboratory dryer. These data provides us information if the product or the dryer is the bottleneck for the optimisation. If the optimization is justified geometry of the dryer, air mass flows, temperature, and humidity profiles inside the dryer as well as initial water content in the drying material, initial temperature of the products and the load of the dryer are required. Some of the previously mentioned data are only used to check if the chamber dryer is working properly, while the others are used as the initial parameters necessary for software simulation. In this paper two models for calculating the optimal drying parameters were used. The first model was developed from the comprehensive theory of the moisture migration during isothermal drying. The calculation software for setting up the non - isothermal drying regimes was reported in our previous papers. It is important to say that this model was not able to adequately predict the temperature raise within the drying products. In order to simulate the raise of the temperature of the roofing tiles during drying the second model was used. This simple receding drying front model was firstly reported by Kitcher. If both models are used simultaneously it is possible to calculate air temperatures, product temperature, absolute and relative humidity of the drying air, moisture content of the product, drying rate etc ... It is important to mention that this approach can lead to the recommendations for changes inside the dryer before an optimized situation is achieved. One example of such situations is described in this paper in details

Method for avoiding cracks during drying of masonry units made of illite raw material

Drying is one of the most important steps in the production process of masonry units. In order to prevent the formation of cracks during drying information's about the moisture migration rate variability as well as the material strength variability through drying are necessary. The main goal of this paper was to find a solution how to prevent the crack formation at the beginning (during the first hour) of the drying for the drying sensitive illite raw material. The first step was to record a series of isothermal Deff - MR curves at different drying air temperatures and constant drying air velocity and humidity. As it was already reported all moisture transport mechanisms during isothermal drying are visible on those curves. Characteristic spots registered on these curves were then transposed on the experimentally registered figure material strength us moisture content. It was found that the material strength for the cracked masonry units at the beginning of drying was around 0.09 MPa and that the time of cracking was near the characteristic spot B. Registered material strength and the crack time position (spot B) has additionally confirmed that the drying sensitivity of the raw material are obviously related with the present clay mineral constituents structure and the initial moisture content of the green heavy clay units. Using the Deff values registered for each experiment in the spot B we were able to calculate the maximal moisture transport rate and consequently the proper drying air parameters which are safe and which will not initialize the formation of the cracks at the beginning of the drying