Smeared and unsmeared chiral vertex operators

We prove unboundedness and boundedness of the unsmeared and smeared chiral vertex operators, respectively. We use elementary methods in bosonic Fock space, only. Possible applications to conformal two - dimensional quantum field theory, perturbation thereof, and to the perturbative construction of the sine-Gordon model by the Epstein-Glaser method are discussed. From another point of view the results of this paper can be looked at as a first step towards a Hilbert space interpretation of vertex operator algebras.Comment: 18 pages, latex, no figure

Convex Hulls, Oracles, and Homology

This paper presents a new algorithm for the convex hull problem, which is based on a reduction to a combinatorial decision problem POLYTOPE-COMPLETENESS-COMBINATORIAL, which in turn can be solved by a simplicial homology computation. Like other convex hull algorithms, our algorithm is polynomial (in the size of input plus output) for simplicial or simple input. We show that the ``no''-case of POLYTOPE-COMPLETENESS-COMBINATORIAL has a certificate that can be checked in polynomial time (if integrity of the input is guaranteed).Comment: 11 pages, 2 figure

Gauge Independence of the S-Matrix in the Causal Approach

The gauge dependence of the time-ordered products for Yang-Mills theories is analysed in perturbation theory by means of the causal method of Epstein and Glaser together with perturbative gauge invariance. This approach allows a simple inductive proof of the gauge independence of the physical S-matrix.Comment: 19 pages, latex, 1 figur

Proper Crime Recording as an Effective Feedback Tool in Articulating a Crime Policy

Crime policy is subject to the policy process just like other governmental policies. An effective crime policy is one that reduces the amount of crime in a police department’s jurisdiction, e.g., the city. Accordingly, crime policy consists of the same policy components – agenda setting, formulation, implementation, and feedback. The implementation of any crime policy depends on the information collected by police departments, often through crimes reported to the department via 9-1-1 calls or brought to a police officer’s attention through proactive police work. The success of that police work relative to the reported crime first depends on whether the type of crime is recorded correctly so that investigative follow-up, if necessary, can be conducted efficiently and properly. Accordingly, police departments that have appropriate internal controls to assess the quality of their crime recording efforts can provide relevant feedback to the command staff and political leaders responsible for setting the agenda and reformulating policy when necessary. This paper will examine the Atlanta Police Department’s efforts in improving its crime recording procedures in 2002-2003 and the changes that led to sustained crime reductions following 2002

Space-Time-Domain Decomposition for Optimal Control Problems Governed by Linear Hyperbolic Systems

In this article, we combine a domain decomposition method in space and time for optimal control problems with PDE-constraints described in [2] to a simultaneous space-time decomposition applied to optimal control problems for systems of linear hyperbolic equations with distributed control. We thereby extend the recent work [31, 32] and answer a long standing open question as to whether the combination of time- and space-domain decomposition for the method under consideration can be put into one single convergent iteration procedure. The algorithm is designed for a semi-elliptic system of equations obtained from the hyperbolic optimality system by the way of reduction to the adjoint state. The focus is on the relation to the classical procedure introduced by P. L. Lions [25] for elliptic problems.In this article, we combine a domain decomposition method in space and time for optimal control problems with PDE-constraints described in [2] to a simultaneous space-time decomposition applied to optimal control problems for systems of linear hyperbolic equations with distributed control. We thereby extend the recent work [31, 32] and answer a long standing open question as to whether the combination of time- and space-domain decomposition for the method under consideration can be put into one single convergent iteration procedure. The algorithm is designed for a semi-elliptic system of equations obtained from the hyperbolic optimality system by the way of reduction to the adjoint state. The focus is on the relation to the classical procedure introduced by P. L. Lions [25] for elliptic problems

The New Orleans Police Department: Melding Police and Policy to Dramatically Reduce Crime in the City of New Orleans

In 1996, the New Orleans Police Department implemented the COMSTAT management and accountability style of policing. Within three years of that implementation, murder was cut by over fifty percent and violent crime fell by nearly the same amount; overall crime was cut by over one-third compared to just three years ago. This dissertation seeks to explore the reasons crime declined so rapidly in New Orleans post-COMSTAT implementation, compared to crime in the rest of the country. Drawing on political and criminological theories of policing as well as sociological theories, variables unique to each set of theories were identified and tested alone and against competing explanations. Utilizing higher-ordered time series methodology, two analyses were conducted. The first utilized interrupted time-series analysis to identify the nature of COMSTAT\u27s impact on New Orleans\u27 crime trends, measured as changes in the current quarter compared to the same quarter of the preceding year. The results show that while COMSTAT had a significant impact on the crime trends, the effects were short-lived. The second analysis utilized traditional time series methodology to examine the impacts of the individual variables on the overall crime trends. The results show that while policing variables and sociological variables have little effect on the overall crime trends both individually and when tested together, the findings indicate policing variables play a larger role than sociological variables when included together. As another independent test of the effects of crime, public opinion data obtained via the University of New Orleans\u27 Survey Research Center from 1986-2004 show that the public was very positive towards the NOPD\u27s efforts in dramatically reducing crime and fear of crime in New Orleans during this period. The overall results for policy makers then indicates that reductions in crime resonate positively with city residents and future policy decisions should be made with that goal in mind

“Aku Siswa Anti Bullying”: Layanan Psikoedukasi untuk Mencegah Bullying di Sekolah

Permasalahan tentang kekerasan dan bullying secara verbal atau fisik masih rentan terjadi terutama di lingkungan sekolah. Tujuan kegiatan layanan adalah peserta didik dapat mengetahui, memahami pentingnya pencegahan perilaku bullying di lingkungan sekolah dan menciptakan lingkungan belajar yang aman dan nyaman. Kegiatan dilakukan bersamaan dengan mahasiswa praktik Pembelajaran Lapangan di salah satu SMP. Peserta layanan psikoedukasi sejumlah 78 siswa kelas VII. Penulis berdiskusi bersama Guru Bimbingan dan Konseling (BK) untuk membuat Rencana Pemberian Layanan (RPL) dan menyiapkan modul layanan psikoedukasi. Hasil pemberian layanan menunjukkan hampir semua siswa mengetahui tentang topik layanan yang diberikan, mendapatkan pemahaman baru bahwa tidak baik melakukan bullying, dan siswa merasa senang dan paham mengenai perilaku bullying.Problems about verbal or physical violence and bullying are still vulnerable, especially in the school environment. The purpose of service activities is that students can know, understand the importance of preventing bullying behaviour in the school environment and create a safe and comfortable learning environment. The activity was carried out simultaneously with students practicing Field Learning in one of the junior high schools. Participants in the psychoeducation service were 78 grade VII students. The author discusses with the Guidance and Counselling teacher to make a Service Delivery Plan (RPL) and prepare a psychoeducation service module. The results of service delivery show that almost all students know about the topic of the services provided, gain a new understanding that it is not good to bully friends or other people, and students feel happy and understand bullying behaviour