Dynamical analysis of an iterative method with memory on a family of third-degree polynomials

Qualitative analysis of iterative methods with memory has been carried out a few years ago. Most of the papers published in this context analyze the behaviour of schemes on quadratic polynomials. In this paper, we accomplish a complete dynamical study of an iterative method with memory, the Kurchatov scheme, applied on a family of cubic polynomials. To reach this goal we transform the iterative scheme with memory into a discrete dynamical system defined on R2. We obtain a complete description of the dynamical planes for every value of parameter of the family considered. We also analyze the bifurcations that occur related with the number of fixed points. Finally, the dynamical results are summarized in a parameter line. As a conclusion, we obtain that this scheme is completely stable for cubic polynomials since the only attractors that appear for any value of the parameter, are the roots of the polynomial.This paper is supported by the MCIU grant PGC2018-095896-B-C22. The first and the last authors are also supported by University Jaume I grant UJI-B2019-18. Moreover, the authors would like to thank the anonymous reviewers for their comments and suggestions

Comparing Open-Ended Choice Experiments and Experimental Auctions: An Application to Golden Rice

We use two different experimental valuation methods to estimate consumer demand for genetically-modified golden rice. The first is an open-ended choice experiment (OECE) where participants name the quantities of golden rice and conventional rice demanded at each of several price combinations, one of which will be randomly chosen as binding. This allows us to estimate market demand by aggregating demand across participants. This estimate of market demand also allows us to estimate own-price elasticity and consumer surplus for golden rice. Comparing willingness-to-pay (WTP) estimates from the OECE with those from a uniform-price auction, we find that OECE WTP estimates exhibit less affiliation across rounds, and the effects of positive and negative information under the OECE are more consistent with prior expectations and existing studies. We also find that while auction WTP estimates more than double across five rounds, OECE WTP estimates are stable across rounds and are always roughly equal to those from the final auction round.choice experiments, experimental auctions, golden rice, valuation

Study of the dynamics of third-order iterative methods on quadratic polynomials

In this paper, we analyse the dynamical behaviour of the operators associated with multi-point interpolation iterative methods and frozen derivative methods, for solving nonlinear equations, applied on second-degree complex polynomials. We obtain that, in both cases, the Julia set is connected and separates the basins of attraction of the roots of the polynomial. Moreover, the Julia set of the operator associated with multi-point interpolation methods is the same as the Newton operator, although it is more complicated for the frozen derivative operator. We explain these differences by obtaining the conjugacy function of each method and by showing that the operators associated with Newton's method and multi-point interpolation methods are both conjugate to powers of z.The authors thank Professors X. Jarque and A. Garijo for their help. The authors also thank the referees for their valuable comments and suggestions that have improved the content of this paper. This research was supported by Ministerio de Ciencia y Tecnologia MTM2011-28636-C02-02 and by Vicerrectorado de Invetigacion, Universitat Politecnica de Valencia, PAID-06-2010-2285Cordero Barbero, A.; Torregrosa Sánchez, JR.; Vindel Cañas, P. (2012). Study of the dynamics of third-order iterative methods on quadratic polynomials. International Journal of Computer Mathematics. 89(13):1826-1836. https://doi.org/10.1080/00207160.2012.687446S182618368913Amat, S., Busquier, S., & Plaza, S. (2006). A construction of attracting periodic orbits for some classical third-order iterative methods. Journal of Computational and Applied Mathematics, 189(1-2), 22-33. doi:10.1016/j.cam.2005.03.049Amat, S., Bermúdez, C., Busquier, S., & Plaza, S. (2008). On the dynamics of the Euler iterative function. Applied Mathematics and Computation, 197(2), 725-732. doi:10.1016/j.amc.2007.08.086Amat, S., Busquier, S., & Plaza, S. (2010). Chaotic dynamics of a third-order Newton-type method. Journal of Mathematical Analysis and Applications, 366(1), 24-32. doi:10.1016/j.jmaa.2010.01.047Blanchard, P. (1995). The dynamics of Newton’s method. Proceedings of Symposia in Applied Mathematics, 139-154. doi:10.1090/psapm/049/1315536Cordero, A., & Torregrosa, J. R. (2010). On interpolation variants of Newton’s method for functions of several variables. Journal of Computational and Applied Mathematics, 234(1), 34-43. doi:10.1016/j.cam.2009.12.002Cordero, A., Hueso, J. L., Martínez, E., & Torregrosa, J. R. (2009). Multi-Point Iterative Methods for Systems of Nonlinear Equations. Lecture Notes in Control and Information Sciences, 259-267. doi:10.1007/978-3-642-02894-6_25Cordero, A., Hueso, J. L., Martínez, E., & Torregrosa, J. R. (2010). Iterative methods for use with nonlinear discrete algebraic models. Mathematical and Computer Modelling, 52(7-8), 1251-1257. doi:10.1016/j.mcm.2010.02.028Curry, J. H., Garnett, L., & Sullivan, D. (1983). On the iteration of a rational function: Computer experiments with Newton’s method. Communications in Mathematical Physics, 91(2), 267-277. doi:10.1007/bf01211162Douady, A., & Hubbard, J. H. (1985). On the dynamics of polynomial-like mappings. Annales scientifiques de l’École normale supérieure, 18(2), 287-343. doi:10.24033/asens.1491Frontini, M., & Sormani, E. (2003). Some variant of Newton’s method with third-order convergence. Applied Mathematics and Computation, 140(2-3), 419-426. doi:10.1016/s0096-3003(02)00238-2Gutiérrez, J. M., Hernández, M. A., & Romero, N. (2010). Dynamics of a new family of iterative processes for quadratic polynomials. Journal of Computational and Applied Mathematics, 233(10), 2688-2695. doi:10.1016/j.cam.2009.11.017Özban, A. . (2004). Some new variants of Newton’s method. Applied Mathematics Letters, 17(6), 677-682. doi:10.1016/s0893-9659(04)90104-8PLAZA, S. (2001). CONJUGACIES CLASSES OF SOME NUMERICAL METHODS. Proyecciones (Antofagasta), 20(1). doi:10.4067/s0716-09172001000100001Plaza, S., & Romero, N. (2011). Attracting cycles for the relaxed Newton’s method. Journal of Computational and Applied Mathematics, 235(10), 3238-3244. doi:10.1016/j.cam.2011.01.010F.A. Potra and V. Pták,Nondiscrete Introduction and Iterative Processes, Research Notes in Mathematics Vol. 103, Pitman, Boston, MA, 1984

Pelatihan dan Pemahaman untuk Menembus Pasar Modern Bagi Kelompok USAha Jamur di Parongpong Cimahi

Tujuan kegiatan Pelatihan dan Pemahaman untuk Menembus Pasar Modern bagi Kelompok Usaha Jamur di Parongpong Cimahi adalah peningkatan pengetahuan para petani jamur dan pengolah jamur tentang tuntutan dan mekanisme untuk memenuhi kualifikasi dari pasar modern khususnya di Yogya group, termasuk peningkatan pengetahuan sortir produk, kemasan produk untuk pengiriman, informasi mengenai kebutuhan pasar mengenai jamur dan produk olahan jamur, dan peningkatan pengetahuan dan pemahaman tentang pengelolaan keuangan secara sederhana.Pada bulan Mei 2014 bekerjasama dengan Yogya Supermarket diselenggarakan pertemuan dan diskusi mengenai syarat, mekanisme, dan kriteria agar dapat menjadi pemasok, harga , syarat pembayaran serta kualitas produk serta dilakukan pula peragaan bagaimana caranya mengemas jamur merang untuk dapat diterima di supermarket. Pada bulan Juli 2014 diselenggarakan pelatihan manajemen keuangan sederhana untuk para petani dan pengusaha produk olahan jamur, namun ternyata peserta yang datang ke pelatihan merupakan pengusaha dari berbagai jenis USAha. Karena itu ada permintaan dari Koperasi Mitra Sejahtera untuk memberikan pelatihan lebih lanjut mengenai pengelolaan keuangan untuk berbagai pengusaha , bukan hanya untuk petani jamur dan Perusahaan pengolah jamur. Selain itu ada pula permintaan untuk dibantu dalam proses pembudidayaan bibit jamur.Pelaksanaan kegiatan tersebut dinilai berhasil dengan hadirnya peserta sesuai target serta besarnya antusias peserta. Bagi para peserta, kegiatan yang dilakukan memberikan manfaat yang besar karena mereka menjadi memahami tuntutan pasar modern mengenai kualitas produk jamur merang maupun kripik jamur. Kesempatan terbuka namun hambatannya adalah masalah tingginya kualitas yang diminta pasar modern serta pemasok harus dapat menjual secara kredit. Harga jual ke supermarket Yogya adalah Rp 15.000/kg dengan syarat bahwa jamur merang yang sesuai standar sudah dikemas rapih, diterima di tempat dan pemasok bersedia dibayar 2 minggu kemudian. Kendala yang tidak mudah diatasi adalah bahwa produk jamur merang yang dihasilkan besarnya tidak sama, sehingga akan banyak produk yang tidak dapat dijual, sehingga sementara ini masih lebih baik untuk dijual secara borongan kepada pengumpul dengan harga Rp 8.500-Rp 10.000/kg dibayar tunai atau 1-3 hari kemudian. Para peserta pelatihan manajemen keuangan juga berpendapat bahwa mereka mendapatkan pencerahan bahwa apa yang telah mereka lakukan selama ini keliru dan bila tidak diperbaiki maka USAha mereka tidak dapat berkembang dengan efisien dan efektif serta sulit mendapatkan kredit. Namun untuk melakukan manajemen keuangan sederhana perlu dilakukan pelatihan dan pendampingan yang berkelanjutan.Pelaksanaan kegiatan pengabdian dapat berjalan dengan baik karena adanya dukungan yang baik dari Seksi Pengembangan Sosial Ekonomi (PSE) Paroki St. Ignatius Cimahi dan Koperasi Kredit Mitra Sejahtera (KKMS) yang telah menyediakan tempat pelatihan dan mensosialisasikan kegiatan pengabdian ini

The Effects of Dry Spell on Eggplant Production in Batangas City, Philippines

According to the Food and Agriculture Organisation of the United Nations, there is an unclear understanding as to the extent to which natural disasters cause significant impacts to the agriculture sector, especially on its subsectors. Most studies holistically focus on the agriculture sector as a whole and fail to address sector-specific industries. This research was conducted to identify the nature and extent of effects of dry spell on a specific sector, eggplant production, in Batangas City in the Philippines. To determine the effects of the dry spell, 71 eggplant farmers situated in the barangays (villages) of Tabangao Dao, Pinamucan East, and Sto. Niño in Batangas City were interviewed. The data was analyzed using frequency and mean analysis as well as cost and return analysis. The respondents reported that the dry spell delayed their transplanting activity, which led to delays in fertilizer application. The dry spell also decreased the quality of the eggplants, as well as increased the number of twisted-shaped eggplants, fruits with brown streaks and lesions on the skin, and fruits which were stunted and thin. Consequently, there was a decrease of good-graded eggplants and the increase in semi-good and rejected eggplants. Lastly, on the average, there was a 105 kg per harvest per hectare decrease in eggplant production in Batangas City, which resulted to a PhP14,880.85 reduction in the expected income of the farmers. It is recommended that the government provide a communal water source, subsidize the costs of some production inputs, and link the farmers to technology developers and agriculture experts who can help develope appropriate coping mechanisms against dry spells. Further, the eggplant farmers must be encouraged to practice mulching, contour farming, and crop rotation to minimize possible production losses from dry spells

Developing Agri-based Technopreneurs in the Academe: The Case of Two DOST-Funded Projects in the University of the Philippines Los Baños

This paper assesses the outcome of two Department of Science and Technology (DOST)–funded projects geared towards promoting technopreneurship among students of the University of the Philippines Los Baños (UPLB). It describes the various technopreneurial trainings and other inputs under the Agriculture, Foresty, and Natural Resources (AFNR) project. Then, using an action research design, it documents and examines the experiences of twenty-six (26) student-technopreneurs who conducted start-up businesses for five months using three UPLB-developed technologies, with supplementary funds coming from the Philippine Council for Industry, Energy, and Emerging Technology Research and Development (PCIEERD-DOST). The study uses primary and secondary data from the student-technopreneurs, validated through key informant interviews, to gain insights into the process of running the start-ups, including the challenges encountered and lessons learned, and then evaluates their performance using three parameters, namely, financial performance, entrepreneurial competencies developed, and the number of businesses registered after the project. Results show that the student-technopreneurs under the high-end cheese and by-products track were the most financially successful, followed by those under the fruit juice and puree track. Those under the microbial rennet were the least successful. All of the participants reportedly gained personal entrepreneurial competencies, the most important of which being acquisition of technological know-how. On the overall, the two projects are assessed to be successful. Lastly, only seven registered their businesses as most perceived that their current production scale was too small to require business registration. The paper then provides future directions for research and recommendations on how to improve the conduct of similar projects based on the experiences of the participants and the insights from the project management team

Mineralogical and thermal characterization of borate minerals from Rio Grande deposit, Uyuni (Bolivia)

Large volumes of borate resources exist in Bolivia, with the most important being the Rio Grande deposit, located close to the Salar of Uyuni. Here, borates occur in beds and lenses of variable thickness. A mineralogical and thermal characterization of borates from the Rio Grande was made using XRD, FTIR, SEM and DTA TG. The deposit is mainly composed of B2O3, CaO and Na2O, with minor contents of MgO and K2O. Some outcrops are constituted by pure ulexite aggregates (NaCaB5 O6(OH)6 5H2O) of fibrous morphology; in other cases, gypsum, calcite and halite also are present. The thermal decomposition of ulexite begins at 70 C and proceeds up to *550 C; this decomposition is attributed to dehydration and dehydroxylation processes in three steps: at 115, 150 300 and 300 550 C. The last mass loss of 1 5 % at 800 C is due to the removal of Cl2 from the decomposition of halite. DTA shows two endothermic events related to the removal of water; in the first, NaCaB5O6(OH)6 5H2O evolved from NaCaB5O6(OH)6 3H2O, at 108 116 C; in the second, NaCaB5O6(OH)6 is formed at 180 185 C and NaCaB5O9 (amorphous) is formed at 300 550 C. The exothermic peak (658 720 C) is related to the crystallization of NaCaB5O9. A small endothermic peak appears due to the halite melting. Later, another endothermic event (821 877 C) appears, which is related to the decomposition of NaCaB5O9 into a crystalline phase of CaB2O4 and amorphous NaB3O5. The XRD pattern evidences that, at 1050 C, CaB2O4 still remains in the crystalline state

Obtención de vidrio a partir de residuos de la minería del estaño en Bolivia

Manufacturing of glass from tin mining tailings in Bolivia Tailings from mining activities in Bolivia represent an environmental problem. In the vicinity of the tin mines of Llallagua,Potosí department, there are large dumps and tailings. We present a study of the use of these wastes as raw materials for the manufacture of glass. This procedure aims to contribute to environmental remediation of mining areas through the vitrification, a process which offers an alternative for stabilization of hazardous waste. In addition, the marketing of the obtained product would provide an additional income to the mining areas. For this study three samples of mining waste, with grain size between sand and silt, were used. The chemical composition of these raw materials, determined by X-ray fluorescence, is granitic, with high contents of heavy metals. On the basis of its composition, glass were made from silica glass by adding CaCO3 and Na2CO3. The thermal cycle has been determined from TDA. Tg values of glass range from 626º to 709 °C. Leaching tests of the obtained glasses confirm their capacity to retain heavy metals

Estudio de marcadores tumorales citológicos e histológicos relacionados con las alteraciones cromosómicas de tumores sólidos.

Si bien hay diferencias en cuanto a la incidencia y la tasa de morbilidad y mortalidad de cada una de las formas de cáncer en los diversos países, se calcula que aproximadamente una de cada cinco personas en el mundo mueren de cáncer. Aunque ha habido considerables avances en el tratamiento, incluyendo procedimientos de alta precisión en cirugía y protocolos detallados para radio y quimioterapia, los tumores malignos siguen siendo una de las causas de muerte más prominentes de la sociedad moderna. Las estrategias para el tratamiento dependen de un diagnóstico preciso y temprano. Algunos tumores presentan dificultades para clasificarlos, lo que lleva consigo una incertidumbre en el pronóstico y tratamiento. Los tumores sólidos tanto de órganos como de tejidos blandos y óseo, son un grupo de neoplasias muy diverso, que ocurren en todas las edades. El diagnóstico/ pronóstico puede ser complicado y el dilema del diagnóstico diferencial depende frecuentemente de los métodos histopatológicos y radiológicos. El presente proyecto intenta correlacionar los parámetros histopatológicos e inmunohistoquímicos con las aberraciones cromosómicas que ellos presentan a los efectos de contribuir en el diagnóstico y tratamiento más eficientes. La detección de alteraciones cromosómicas como anillos, cromosomas dicéntricos, deleciones, traslocaciones, etc., que están asociadas con tipos específicos de tumores sólidos relacionándolos con su morfología permitirá contribuir a un mejor diagnóstico y por ende tratamientos más precisos, ya que ciertos tumores, a pesar de morfología similar pueden tener comportamiento diferente