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Abstract

Decision making in material selection plays important role in selecting appropriate material based on design and manufacturing attributes. Proposing a new material is always a challenging task so the researchers used Decision making assistance tools. In the Present paper the application of Multi-Attribute Decision Making (MADM) methods are applied to the piston material selection for optimal design process. Comparative study of subjective and objective criteria weights on selected MADM methods are done. Sensitivity analysis is conducted to prove the consistency in performance score ranking order as the criteria weights for each alternative varies.

Abstract

Catalytic cracking of volatiles derived from wet pig manure (WPM), dried pig manure and their compost was investigated over Ni/Al2O3 and Ni-loaded on lignite char (Ni/C). Non-catalytic pyrolysis of WPM resulted in a carbon conversion of 43.3% and 18.5% in heavy tar and light tar, respectively. No tar was formed when Ni/Al2O3 was introduced for WPM gasifi cation and the gas yield signifi cantly reached to a high value of 64.4 mmol/g at 650oC. When Ni/C was employed, 5.9% of carbon in the light tar was found at 650oC, revealing that the Ni/C is not active enough for cracking of tarry materials. The pyrolysis vapor was cracked completely and gave a H2-rich tar free syngas in high yield. High water amount of WPM promotes steam gasifi cation of char support, causing the deactivation of Ni/C. Such a study may be benefi cial to the development of livestock manure catalytic gasifi cation technology.

Abstract

The purpose of the presented study was to determine the best mineral composition of media and plant growth regulators in the micropropagation of the ‘Gisela 5’ (Prunus cerasus × P. canescens) dwarf sweet cherry rootstock. Nodal explants from young healthy shoots were excised and cultured on Murashige and Skoog medium without growth regulators. In vitro raised shoot tips were transferred to three culture media including Murashige and Skoog (MS), Driver and Kuniyuki (DKW) and Lloyd and McCown (WPM) containing benzyl adenine (BA) (0.5, 1 or 2 mg·l−1) in combination with kinetin (Kin) at 0 or 0.5 mg·l−1. WPM and DKW media were proving to be the most effective, resulting in a higher percentage of shoot multiplication and shoot number as compared to MS. BA in concentration 2 mg·l−1 resulted in the highest number of microshoots per explant (3.1). For rooting, 0, 0.5, 1 or 2 mg·l−1 indole-3-butyric acid (IBA) on MS, DKW and WPM media were tested. WPM medium containing 2 mg·l−1 IBA was most effective for rooting (93.7%) in comparison to MS (53.1%) and DKW (14.0%). Rooted plantlets were successfully hardened and established in pots.

Mikrorozmnażanie wisienki stepowej (Cerasus fruticosa Pallas)

Abstract

The biological soil crusts (BSCs) in the NW Negev cause local water redistribution by increasing surface runoff. The effects of pore clogging and swelling of organic and inorganic crust components were intensively investigated in earlier studies. However, the effect of water repellency (WR) was not addressed systematically yet. This study investigates subcritical WR of BSCs in three different study sites in the NW Negev. For this purpose, three common methods to determine soil WR were used: (i) the repellency index (RI) method (ii) the water drop penetration time (WDPT) test and (iii) the Wilhelmy plate method (WPM). Furthermore, the potential influence of WR on local water redistribution is discussed and the applied methods are compared. We found the BSC to be subcritically water repellent. The degree of WR may only affect water redistribution on a microscale and has little influence on the ecosystem as a whole. The RI method was clearly the most appropriate to use, whereas the WDPT and the WPM failed to detect subcritical WR.

Abstract

A proper edge-coloring of a graph G with colors 1, . . . , t is an interval t-coloring if all colors are used and the colors of edges incident to each vertex of G form an interval of integers. A graph G is interval colorable if it has an interval t-coloring for some positive integer t. Let be the set of all interval colorable graphs. For a graph G ∈ , the least and the greatest values of t for which G has an interval t-coloring are denoted by w(G) and W(G), respectively. In this paper we first show that if G is an r-regular graph and G ∈ , then W(G⃞Pm) ≥ W(G) + W(Pm) + (m − 1)r (m ∈ N) and W(G⃞C2n) ≥ W(G) +W(C2n) + nr (n ≥ 2). Next, we investigate interval edge-colorings of grids, cylinders and tori. In particular, we prove that if G⃞H is planar and both factors have at least 3 vertices, then G⃞H N and w(G⃞H) ≤ 6. Finally, we confirm the first author’s conjecture on the n-dimensional cube Qn and show that Qn has an interval t-coloring if and only if n ≤ t ≤

Abstract

Human resources management in agricultural farms is of particular importance in the context of the particularities of labor in agriculture, which is different from other economic sectors. Since labor is the most important production factor of any economic activity, labor productivity is the most used in the evaluation of economic efficiency. Accelerating the productivity growth is related to understanding content and its meaning, major factors of influence and way of exploitation. To emphasize human resource management and to illustrate the way of calculation of labor productivity, the study was conducted in an ecological farm with a vegetable profile of Iaşi County, Romania. The labor productivity has been used in the evaluation of economic efficiency, for three major crops: wheat, maize and potatoes. We used three indicators: average efficiency factor of production land use, WPm; the average productivity of labor in physical units, WLm; labor productivity, WH; labor productivity in monetary value, WV. To increase the labor productivity and efficiency of human resources there were organised training courses and programs both of managers and directly involved productive staff, but also there were introduced new production technologies that lead to ease and make efficient the staff work.

Sci. 2003;58(23):5195-5210. DOI: 10.1016/j.ces.2003.08.014. Zarzycki R, Chacuk A. Absorption: Fundamentals and Applications. Oxford: Pergamon Press; 1993. van Swaaij WPM, Versteeg GF. Mass transfer accompanied with complex reversible chemical reactions in gas-liquid systems: an overview. Chem Eng Sci. 1992;47:3181-3195. DOI: 10.1016/0009-2509(92)85028-A. Derks PWJ, Kleingeld T, van Aken C, Hogendoorn JA, Versteeg GF. Kinetics of absorption of carbon dioxide in aqueous piperazine solutions. Chem Eng Sci. 2006;61(20):6837-6854. DOI:10.1016/j.ces.2006

References Ali SA. Kinetic study of the reaction of diethanolamine with carbon dioxide in aqueous and mixed solvent systems - application to acid gas cleaning. Sep Purif Technol. 2004;38:281-296. DOI 10.1016/j.seppur.2003.12.004. Laddha SS, Danckwerts PV. Reaction of CO 2 with ethanolamines: kinetics from gas-absorption. Chem Eng Sci. 1981;36:479-482. DOI 10.1016/0009-2509(81)80135-2. Versteeg GF, van Swaaij WPM. On the kinetics between CO 2 and alkanolamines both in aqueous and non-aqueous solutions - I. Primary and secondary amines. Chem Eng Sci. 1988

References Grzywaczewski, Z., Niezawodność statku transportowego w świetle awaryjności w polskiej marynarce handlowej, WIM, Gdańsk-Szczecin 1971. Foki, J., G., Niezawodność eksploatacyjna urządzeń technicznych, WMON, Warszawa 1973. Grzesiak, K., Niezawodność urzą dzeń elektronicznych, PWN, Warszawa 1965. Grzywaczewski, Z., Niezawodność statków, WPM Wema, Warszawa 1988. Czajgucki, J., Z., Niezawodność spalinowych siłowni okrętowych, Wydawnictwo Morskie, Gdańsk 1984. Centrum Techniki Okrętowej w Gdańsku, baza danych Polship http://polship.cto.gda.pl Dokumentacja