On the signature of certain intersection forms

We prove a conjecture of Zuber on the signature of intersection froms associated with affine algebras of type A.Comment: 10 pages, Amste

Number of Jordan blocks of the maximal size for local monodromies

We prove formulas for the number of Jordan blocks of the maximal size for local monodromies of one-parameter degenerations of complex algebraic varieties where the bound of the size comes from the monodromy theorem. In case the general fibers are smooth and compact, the proof calculates some part of the weight spectral sequence of the limit mixed Hodge structure of Steenbrink. In the singular case, we can prove a similar formula for the monodromy on the cohomology with compact supports, but not on the usual cohomology. We also show that the number can really depend on the position of singular points in the embedded resolution even in the isolated singularity case, and hence there are no simple combinatorial formulas using the embedded resolution in general.Comment: 23 page

Studies on the growth of voids in amorphous glassy polymers

Numerical studies are presented of the localized deformations around voids in amorphous glassy polymers. This problem is relevant for polymer-rubber blends once cavitation has taken place inside the rubber particles. The studies are based on detailed finite element analyses of axisymmetric or planar cell models, featuring large local strains and recent material models that describe time-dependent yield, followed by intrinsic softening and subsequent strain hardening due to molecular orientation. The results show that plasticity around the void occurs by a combination of two types of shear bands, which we refer to as wing and dog-ear bands, respectively. Growth of the void occurs by propagation of the shear bands, which is driven by orientational hardening. Also discussed is the evolution of the local hydrostatic stress distribution between voids during growth, in view of possible craze initiation.

Academic Study of Indonesian Islam: A Biographical Account, 1970-2014

In the humanities, including religious studies, personal factors often play a role in the selection of topic and methodology of research. This autobiographical sketch gives an overview of a long career in the study of religion in Indonesia, from the selection of the topic for doctoral research, through various jobs and academic projects until some work written in a period of retirement. The author’s background of liberal Catholicism with much interest in non-official popular religiosity, has influenced an approach in Islamic Studies and a selective attention for the boundaries between official and more popular religiosity, for literary and artistic expressions rather than for rigid doctrinal traditions. This history is told from field work to pesantren education in the early 1970s, the variety of Islamic history of Indonesia in the 1980s, until a major work in three volumes on the Catholic traditions of Indonesia in the period 1990-2010.[Dalam ilmu humaniora, termasuk studi keagamaan, faktor-faktor pribadi sering mempengaruhi pemilihan topik dan metodologi penelitian. Uraian biografis ringkas ini menggambarkan perjalanan panjang sebagai peneliti agama di Indonesia, mulai dari pemilihan topik riset disertasi, melewati beragam pekerjaan dan proyek-proyek akademik, sampai dengan beberapa karya yang ditulis sesudah pensiun. Latar belakang penulis sebagai penganut Katolik liberal dan banyak tertarik pada keberagamaan populer non-resmi, mempengaruhi pendekatan dalam pengkajian Islam dan perhatian khusus pada batas-batas antara agama resmi dan agama populer, pada ungkapan-ungkapan sastrawi dan seni daripada tradisi-tradisi doktriner yang kaku. Kisah ini berangkat dari pengalaman penelitian lapangan di lingkungan pendidikan pesantren pada tahun 1970an, kemudian serpihan-serpihan sejarah Indonesia pada tahun 1980an, sampai dengan penulisan tiga jilid buku penting tentang tradisi-tradisi Katolik Indonesia pada tahun 1990-2010.