KAJIAN TENTANG KONTRIBUSI CACING TANAH DAN PERANNYA TERHADAP LINGKUNGAN KAITANNYA DENGAN KUALITAS TANAH

Cacing Tanah atau Earthworm , merupakan makrofauna tanah yang saat ini banyak dibudidayakan untuk berbagai kepentingan. Namun sementara banyak orang yang tidak peduli dengan keberadaan nya dikarena dianggap tidak bermanfaat dan kurang menguntungkan. Fakta menunjukkan bahwa banyak perilaku petani dengan ketidak tahuan nya menggunakan pupuk kimia sintetis untuk untuk meningkatkan produk pertanian namun disisi lain banyak cacing tanah yang mati dikarenakan cacing tanah sangat sensitif terhadap bahan kimia tersebut. Kajian ilmiah ini bertujuan untuk mengungkap kejelasan mengenai peran cacing tanah terhadap lingkungan, hubungannya dengan kesuburan tanah. Kesuburan tersebut berhubungan dengan faktor fisik, kimia dan biologi tanah. Dari kajian ilmiah ini dapat memperjelas peran cacing tanah terhadap lingkungan dan dan menjaga kualitas serta sekaligus memberikan informasi dan warning bagi para petani untuk tidak menggunakan pupuk kimia. Kata Kunci: Cacing tanah, lingkungan, kualitas tanah

Coalgebraic characterizations of context-free languages

Article / Letter to editorLeiden Inst Advanced Computer Science

Cognitive functioning in meningioma patients:A systematic review

This systematic review evaluates relevant findings and methodologic aspects of studies on cognitive functioning in meningioma patients prior to and/or following surgery with or without adjuvant radiotherapy. PubMed and Web of Science electronic databases were searched until December 2015. From 1012 initially identified articles, 11 met the inclusion criteria for this review. Multiple methodological limitations were identified which include the lack of pre-treatment assessments, variations in the number and types of neuropsychological tests used, the normative data used to identify patients with cognitive deficits, and the variety of definitions for cognitive impairment. Study results suggest that most of meningioma patients are faced with cognitive deficits in several cognitive domains prior to surgery. Following surgery, most of these patients seem to improve in cognitive functioning. However, they still have impairments in a wide range of cognitive functions compared to healthy controls. Suggestions are given for future research. Adequate diagnosis and treatment of cognitive deficits may ultimately lead to improved outcome and quality of life in meningioma patients

Coalgebraic semantics of heavy-weighted automata

We study heavy-weighted automata, a generalization of weighted automata in which the weights of the transitions can be any formal power series. We define their semantics in three equivalent ways, and give some examples of how they can provide a more compact representation of certain power series than ordinary weighted automata

Coalgebraic semantics of heavy-weighted automata

We study heavy-weighted automata, a generalization of weighted automata in which the weights of the transitions can be any formal power series. We define their semantics in three equivalent ways, and give some examples of how they can provide a more compact representation of certain power series than ordinary weighted automata

Context-free Coalgebras

In this article, we provide a coalgebraic account of parts of the mathematical theory underlying context-free languages. We characterize context-free languages, and power series and streams generalizing or corresponding to the context-free languages, by means of systems of behavioural differential equations; and prove a number of results, some of which are new, and some of which are new proofs of existing theorems, using the techniques of bisimulation and bisimulation up to linear combinations. Furthermore, we establish a link between automatic sequences and these systems of equations, allowing us to, given an automaton generating an automatic sequence, easily construct a system of behavioural differential equations yielding this sequence as a context-free stream

Coalgebraic semantics of heavy-weighted automata

We study heavy-weighted automata, a generalization of weighted automata in which the weights of the transitions can be any formal power series. We define their semantics in three equivalent ways, and give some examples of how they can provide a more compact representation of certain power series than ordinary weighted automata

Context-free languages, coalgebraically

We give a coalgebraic account of context-free languages using the functor ${\cal D}(X) = 2 \times X^A$ for deterministic automata over an alphabet $A$, in three different but equivalent ways: (i) by viewing context-free grammars as ${\cal D}$-coalgebras; (ii) by defining a format for behavioural differential equations (w.r.t. ${\cal D}$) for which the unique solutions are precisely the context-free languages; and (iii) as the ${\cal D}$-coalgebra of generalized regular expressions in which the Kleene star is replaced by a unique fixed point operator. In all cases, semantics is defined by the unique homomorphism into the final coalgebra of all languages, thus paving the way for coinductive proofs of context-free language equivalence. Furthermore, the three characterizations are elementary to the extent that they can serve as the basis for the definition of a general coalgebraic notion of context-freeness, which we see as the ultimate long-term goal of the present study

Regular expressions for polynomial coalgebras

For polynomial set functors G, we introduce a language of expressions for describing elements of final G-coalgebra. We show that every state of a finite G-coalgebra corresponds to an expression in the language, in the sense that they both have the same semantics. Conversely, we give a compositional synthesis algorithm which transforms every expression into a finite G-coalgebra. The language of expressions is equipped with an equational system that is sound, complete and expressive with respect to G-bisimulation