Peningkatan Hasil Belajar Siswa Kelas IV SDN Inpres 2 Lere Pada Materi Sumber Daya Alam Melalui Model Pembelajaran Problem Solving

Penelitian ini bertujuan untuk meningkatkan hasil belajar IPS materi sumber daya alam melalui penerapan metode Problem Solving. Penelitian ini menggunakan bentuk penelitian tindakan kelas yang dilaksanakan dalam 2 (dua) siklus. Tempat pelaksanaan penelitian di SDN Inpres 2 Lere dengan subjek penelitian seluruh siswa kelas IV yang berjumlah 15 siswa. Metode penelitian menggunakan Penelitian Tindakan Kelas. Pengumpulan data dilakukan melalui observasi, dokumentasi dan tes. Analisis data dilakukan dengan 3 (tiga) tahapan meliputi: reduksi data, penyajian data dan penarikan kesimpulan atau verifikasi. Hasil penelitian menunjukan bahwa melalui penerapan Penerapan metode Problem Solving dapat meningkatkan hasil belajar IPS materi sumber daya alam dari kondisi awal nilairata-rata hasil belajar 53,6 dan 0 siswa (0%) atau tidak ada siswa yang mencapai nilai KKM, ke kondisi akhir siklus II nilai rata-rata hasil belajar siswa 69,6 (di atas nilai KKM), dan 14 siswa (93,3%) mencapai nilai KKM dan 1 siswa (6,6%) yang tidak mencapai KKM di kelas. Jadi dapat disimpulkan bahwa melalui penerapan Penerapan metode Problem Solving dapat meningkatkan hasil belajar IPS materi sumber daya alam pada siswa kelas IV semester I SDN Inpres 2 Lere

Studi Tingkat Pendapatan Petani Sebelum dan Sesudah Konversi Lahan Pertanian ke Perkebunan Kelapa Sawit di Desa Pakawa Kecamatan Pasangkayu Kabupaten Mamuju Utara

The purpose of this study to determine changes in the income level of farmers before and after the conversion of agricultural land into oil palm plantations in the village Pakawa. The research area village of Bamba Apu, Lala, Kumu and Mandar Dua (Salu Apu). With the selection of the sample proportional random sampling as many as 68 families, consisting of 22 families Bunggu Tribe, 22 families Bugis tribe and 24 families Mandar tribe. The results showed that the income level of farmers from the three tribes (Bunggu, Bugis and Mandar) greater after land conversion than before land conversion, socio-economic characteristics of the three tribal farmers are classified in socio-economic conditions are adequate

Wave propagation across interfaces induced by different interaction exponents in ordered and disordered Hertz-like granular chains

We study solitary wave propagation in 1D granular crystals with Hertz-like interaction potentials. We consider interfaces between media with different exponents in the interaction potential. For an interface with increasing interaction potential exponent along the propagation direction we obtain mainly transmission with delayed secondary transmitted and reflected pulses. For interfaces with decreasing interaction potential exponent we observe both significant reflection and transmission of the solitary wave, where the transmitted part of the wave forms a multipulse structure. We also investigate impurities consisting of beads with different interaction exponents compared to the media they are embedded in, and we find that the impurities cause both reflection and transmission, including the formation of multipulse structures, independent of whether the exponent in the impurities is smaller than in the surrounding media. We explain wave propagation effects at interfaces and impurities in terms of quasi-particle collisions. Next we consider wave propagation along Hertz-like granular chains of beads in the presence of disorder and periodicity in the interaction exponents present in the Hertz-like potential, modelling, for instance, inhomogeneity in the contact geometry between beads in the granular chain. We find that solitary waves in media with randomised interaction exponents (which models disorder in the contact geometry) experience exponential decay, where the dependence of the decay rate is similar to the case of randomised bead masses. In the periodic case of chains with interaction exponents alternating between two fixed values, we find qualitatively different propagation properties depending on the choice of the two exponents. In particular, we find regimes with either exponential decay or stable solitary wave propagation with pairwise collective behaviour.Comment: 33 pages, 28 figure

Anyons in integer quantum Hall magnets

Strongly correlated fractional quantum Hall liquids support fractional excitations, which can be understood in terms of adiabatic flux insertion arguments. A second route to fractionalization is through the coupling of weakly interacting electrons to topologically nontrivial backgrounds such as in polyacetylene. Here we demonstrate that electronic fractionalization combining features of both these mechanisms occurs in noncoplanar itinerant magnetic systems, where integer quantum Hall physics arises from the coupling of electrons to the magnetic background. The topologically stable magnetic vortices in such systems carry fractional (in general irrational) electronic quantum numbers and exhibit Abelian anyonic statistics. We analyze the properties of these topological defects by mapping the distortions of the magnetic texture onto effective non-Abelian vector potentials. We support our analytical results with extensive numerical calculations.Comment: 15 pages, 12 figures, supersedes arXiv:1112.3347, to be published in PR

t-SURFF: Fully Differential Two-Electron Photo-Emission Spectra

The time dependent surface flux (t-SURFF) method is extended to single and double ionization of two electron systems. Fully differential double emission spectra by strong pulses at extreme UV and infrared wave length are calculated using simulation volumes that only accommodate the effective range of the atomic binding potential and the quiver radius of free electrons in the external field. For a model system we find pronounced dependence of shake-up and non-sequential double ionization on phase and duration of the laser pulse. Extension to fully three-dimensional calculations is discussed

The East German Cement Cartel : An Inquiry into Comparable Markets, Industry Structure, and Antitrust Policy

Maintaining sufficient levels of competition ranks among the core interests of any national – and increasingly international – antitrust policy; however, the formal proof that a cartel really functioned economically and did not only exist in a legal sense is hard to deliver: market power is not identical to the existence of a legal cartel unless the monopolistic frontier is reached; the legal proof of a cartel does not imply that the market was harmed. From an economic point of view, focusing on legal proof of a cartel is fruitless unless collusion resulted in excess profits or excess revenues. This economic evidence, however, rests empirically on the proper definition of comparable markets, and a sound statistical methodology. When in spring 2003, the German Antitrust Agency (GAA) fined the German cement industry – € 661 million for having established quotas in each of the four market regions through the end of 2001, the legal issue seemed beyond doubt as, beside formal inquiries, two of the industry members had acted as key witnesses. However, the economic implications drawn by the GAA remain doubtful. In this paper, we use the quota agreement in the East German market, the region for which these allegations are undisputed by all major suppliers, as a reference case. We challenge the GAA’s computation of excess income of 10 €/ton on two grounds: (i), the comparative market period chosen, 2002, does not meet the requirements of a reference market, especially regarding a certain level of stability and converging prices; (ii) three parallel developments could have triggered the price decline: the openly announced end of the quota cartel, which generated general price-setting insecurity (ii-a), the price war triggered by one of the oligopolists, who desperately tried to improve poor utilization of capacity and squeeze out competitors (ii-b), and the general decline in construction activity (ii-c). Within the framework of an econometric model based on data of one German cement producer, we find that sufficient levels of competition prevailed throughout the cartel period. Furthermore, the demand structure did not change from 2001 to 2002 so as to suggest a fundamental change in competition. Finally, no excess income or profit can be computed. In fact, we show that the general demand regime estimated for the period 1995 to 2001, which is the period of alleged market power, equally well describes the market condition of 2002. Price war and a collapsing construction market lead suppliers to maintain levels of production and capacity utilization, thus sacrificing profits at the expense of the market shares of small and medium-sized suppliers independently from the cartel issue. This empirical finding of an agreed but ineffective cartel is supported by theoretical evidence on the conditions under which cartels can work effectively – which did not exist in the East: strong import competition, a high level of transparency limiting the effects of „cheap talk“ and spatial pricing that generates local market power in the absence of cartels. Furthermore, general supply-side conditions in the cement industry suggest that a considerable level of imperfect competition is structurally unavoidable; antitrust possibilities that in the short run enforce additional competition based on the wrong assessment of effective collusion may lead to exits and less competition in the long run. We conclude that the methodology described may be useful for antitrust policy as it offers a credible analytical tool to compute excess income and profit. --antitrust,cement,competition,collusion,Germany,econometrics,excess income,excess profit,quota agreement