Organizational stress management

There are plenty of general problems that people at work worry about – increasing job competition, globalization, terrorism, annual appraisals, financial crisis, even new technology. Beside these, employees are put under pressure to meet sales targets, attend meetings on time, fit in with changes in organization by learning and following up new procedures. All these can result different levels of stress. Nowadays, working stress is the fastest growing cause of absence from work. Inefficient management, lack of decision-making by management, excessive working hours, uncertainty as to future employment prospects and the pressure of the job are some of the causes of stress described by employees. Therefore, employers should consider organizational stress as a serious problem and they must take measures to prevent employees suffering stress arising from their work. It can negatively influence the productivity and competitiveness of the organization, and can also increase health insurance costs.stress management, organizational stress, total working system

Улогата на музиката во образовниот процес

Во кривопаланечкото подрачје воспитно-образовната дејност ја вршат две основни училишта и девет нивни подрачни единици, во следниве планински села: Огут, Нерав, Жидилово, Узем, Дурачка Река, Станци, Дубровница, Подржикоњ и Луке. Тоа е состојба на ограничени можности за културен и духовен развој, поради недостаток од библиотеки, театри,концертни сали, музеи, а освен тоа, не секој родител има услови да ги носи децата во поголемите градови каде што има повеќе можности за допир со уметноста. Затоа, улогата на наставникот по музичко образование станува уште позначајна во воспитно-образовниот процес. Под влијание на музиката се формира естетски вкус и ориентациона вредност кон уметничката сцена во светот. Музиката е во функција на развојот на способностите за естетски размислувања и контемплација. Музиката не е само чувство. Во процесот на музичката активност може да се запознаеме со историските епохи и личности, да учиме од најдобрите примери во поезијата, книжевноста, па дури и од некои математички и физички концепти поврзани со звукот, со што ги прошируваме нашите хоризонти на познавањето на светот и себеси

Choice of Grout Curtain type of dam “Rečani” on Orizarska river – Kočani

In the frames of Preliminary design for choice of dam type for dam “Rečani” on river of Orizarska near Kočani, three types of embankment dams were elaborated. Based on the results from geological, hydrogeological, geotechnical investigations and recommendations of the geotechnical model, possible alternatives of the grout gallery and curtain were designed. Structural and geotechnical analyses were performed for each of the solutions. At the end, total costs of dam construction and grout works were calculated. Comparing all important factors, optimal design of the grout curtain was proposed. The selection of the optimal type of embankment dam and grouting curtain was also done with application of multi-criteria optimization, by applying of the method of compromise programming

Reaction mechanism and kinetics of sulfide copper concentrate oxidation at elevated temperatures

Sulfide copper concentrate from domestic ore deposit (Bor, Serbia) was subjected to oxidation in the air atmosphere due to a better understanding of reaction mechanism and oxidation of various sulfides present in the copper concentrate at elevated temperatures. Results of the initial sample characterization showed that concentrate is chalcopyrite–enargite-tennantite type, with an increased arsenic content. Characterization of the oxidation products showed the presence of sulfates, oxysulfates, and oxides. Based on predominance area diagrams for Me-S-O systems (Me = Cu, Fe, As) combined with thermal analysis results, the reaction mechanism of the oxidation process was proposed. The reactions which occur in the temperature range 25 – 1000 °C indicate that sulfides are unstable in the oxidative conditions. Sulfides from the initial sample decomposed into binary copper and iron sulfides and volatile arsenic oxides at lower temperatures. Further heating led to oxidation of sulfides into iron oxides and copper sulfates and oxysulfates. At higher temperatures sulfates and oxysulfates decomposed into oxides. Kinetic analysis of the oxidation process was done using Ozawa’s method in the non-isothermal conditions. The values for activation energies showed that the reactions are chemically controlled and the temperature is the most influential parameter on the reaction rates

Thermal analysis and kinetics of the chalcopyrite-pyrite concentrate oxidation process

The paper presents the results of experimental investigation of the chalcopyrite-pyrite concentrate oxidation in the air. Characterisation of the initial sample and oxidation products was done by ICP-AES, XRD, EDXRF methods. Phase stability diagrams were constructed for Cu-Fe-S-O system at 25, 450, 650 and 900 °C. Equilibrium composition of the charge for the optimal oxidation process was calculated. DTA-TG analysis was used for monitoring the oxidation process. Kinetic parameters in non-isothermal conditions were determined, based on Kissinger and Ozawa methods.Values of activation energies showed that all stages of the oxidation process occur in the kinetic field

EXAMPLES OF LCA METHODOLOGY IMPLEMENTATION IN STEEL INDUSTRY

Steel industry kept pace with actual trends for environmental protection in many ways – through different technological improvements considering environment protection, important share of recycling in the steel production, design of so called “eco-steels”, materials designed according to recent environmental directives and legislatives, etc. In the frame of steel production monitoring, LCA methodology is very important for obtaining an accurate environmental picture of a process, due to the fact that the process should be evaluated over its entire life cycle. A number of tools and methodologies have been developed in recent years to assess the potential environmental impacts associated with a product, process or activity during its entire life cycle. The examples of Life Cycle Assessment (LCA) are used by large steel industrial companies as potentially helpful tool for improving the production processes, efficiency of resource utilization and significantly reduction of waste generation and emissions are presented in this paper

Phase diagram investigation and characterization of alloys in Bi-Ga10Sb90 section of Ga-Bi-Sb system

The results of phase equilibria investigation and characterization of the alloys in the Bi-Ga10Sb90 section of Ga-Bi-Sb system are presented in this paper. Phase diagram of the mentioned section has been calculated according to CALPHAD model, using Pandat software. In the frame of alloys characterization, structural, mechanical and electrical characteristics were determined using SEM-EDX analysis, microhardness and electroconductivity measurements

Seismic Analysis of Pine Flat Concrete Dam

Pine Flat Dam, located on King’s River, east of Fresno, California, was constructed by the US Army Corps of Engineers in 1954 with height of 122 m. The dam’s behavior was extensively studied in the 1970’s and 1980’s at the University of California at Berkeley that provide measured and calculated responses for correlation and comparison. For such purpose the dam was analyzed at action of various seismic excitations by taking in consideration linear and non-linear material properties as well and the effect of wave velocities of the rock foundation. The numerical analysis was carried out by preparation of 3D model of the dam thus applying code SOFiSTiK

Optimization of the arsenic removal process from enargite based complex copper concentrate

Selective arsenic extraction from enargite based complex concentrate from Copper Mine in Bor (Serbia), using sodium hypochlorite as a leaching agent, was investigated in this paper. The aim was to assess the optimal conditions for the most efficient arsenic removal from the investigated concentrate, based on factorial design applied to experimentally obtained data. Five important factors with three factor levels were used as the input variables and experimentally obtained arsenic extraction yield was taken as the output variable. The first and the second final order model equations were obtained. It was found that the leaching temperature had the strongest effect on the arsenic extraction. The strongest positive interaction was between the sodium hypochlorite molar concentration and the stirring speed during extraction

Characterization of the Ga-InSb system: experimental investigation of thermal, structural, mechanical and electrical properties

The materials based on gallium-antimonide are widely used in electronic industry in the production of various electronic devices. The results of characterization of selected alloys in the Ga-InSb system obtained by experimental investigation of some thermal, structural, mechanical and electrical properties are presented in this paper. Applied experimental techniques included: differential thermal analysis, light optical microscopy, scanning electron microscopy with EDX, hardness, micro hardness and electrical conductivity measurements