An Historical and Theological Analysis of Campus Crusade for Christ's Evangelistic Practice in Two American University Contexts

This dissertation, an exercise in practical theology, consists of a critical conversation between the evangelistic practice of Campus Crusade for Christ in two American university contexts, Bryan Stone's ecclesiologically grounded theology of evangelism, and William Abraham's eschatologically grounded theology of evangelism. It seeks to provide these evangelizing communities several strategic proposals for a more ecclesiologically and eschatologically grounded practice of evangelism within a university context. The current literature on evangelism is long on evangelistic strategy and activity, but short on theological analysis and reflection. This study focuses on concrete practices, but is grounded in a thick description of two particular contexts (derived from qualitative research methods) and a theological analysis of the ecclesiological and eschatological beliefs embedded within their evangelistic activities. The dissertation provides an historical overview of important figures, ideas, and events that helped mold the practice of evangelism inherited by the two ministries of this study, beginning with the famous Haystack Revival on Williams College in 1806. Both ministries, Campus Crusade for Christ at Bowling Green State University (Ohio) and at Washington State University, inherited an evangelistic practice sorely infected with many of the classic distortions that both Abraham and Stone attempt to correct. Qualitative research methods detail the direction that Campus Crusade for Christ at Bowling Green State University (Ohio) and Washington State University have taken the practice of evangelism they inherited. Applying the analytical categories that emerge from a detailed summary of Stone and Abraham to qualitative data of these two ministries reveals several ways evangelism has morphed in a manner sympathetic to Stone's insistence that the central logic of evangelism is the embodied witness of the church. The results of this analysis reveal the subversive and pervasive influence of modernity on these evangelizing communities—an influence that warrants several corrective strategic proposals including: 1) re-situating evangelism within a reading of the biblical narrative that emphasizes the present, social, public, and realized nature of the gospel of the kingdom of God rather than simply its future, personal, private, and unrealized dimensions; 2) clarifying the nature of the evangelizing communities and their relationship to the church; and 3) emphasizing the virtues that characterize a new evangelistic exemplar who is incarnational, intentional, humble, and courageous.

The Undecidability of Mitchell's Subtyping Relationship

Mitchell defined and axiomatized a subtyping relationship (also known as containment, coercibility, or subsumption) over the types of System F (with "→" and "∀"). This subtyping relationship is quite simple and does not involve bounded quantification. Tiuryn and Urzyczyn quite recently proved this subtyping relationship to be undecidable. This paper supplies a new undecidability proof for this subtyping relationship. First, a new syntax-directed axiomatization of the subtyping relationship is defined. Then, this axiomatization is used to prove a reduction from the undecidable problem of semi-unification to subtyping. The undecidability of subtyping implies the undecidability of type checking for System F extended with Mitchell's subtyping, also known as "F plus eta".

On the Relationship Between File Sizes, Transport Protocols, and Self-Similar Network Traffic

Recent measurements of local-area and wide-area traffic have shown that network traffic exhibits variability at a wide range of scales self-similarity. In this paper, we examine a mechanism that gives rise to self-similar network traffic and present some of its performance implications. The mechanism we study is the transfer of files or messages whose size is drawn from a heavy-tailed distribution. We examine its effects through detailed transport-level simulations of multiple TCP streams in an internetwork. First, we show that in a "realistic" client/server network environment i.e., one with bounded resources and coupling among traffic sources competing for resources the degree to which file sizes are heavy-tailed can directly determine the degree of traffic self-similarity at the link level. We show that this causal relationship is not significantly affected by changes in network resources (bottleneck bandwidth and buffer capacity), network topology, the influence of cross-traffic, or the distribution of interarrival times. Second, we show that properties of the transport layer play an important role in preserving and modulating this relationship. In particular, the reliable transmission and flow control mechanisms of TCP (Reno, Tahoe, or Vegas) serve to maintain the long-range dependency structure induced by heavy-tailed file size distributions. In contrast, if a non-flow-controlled and unreliable (UDP-based) transport protocol is used, the resulting traffic shows little self-similar characteristics: although still bursty at short time scales, it has little long-range dependence. If flow-controlled, unreliable transport is employed, the degree of traffic self-similarity is positively correlated with the degree of throttling at the source. Third, in exploring the relationship between file sizes, transport protocols, and self-similarity, we are also able to show some of the performance implications of self-similarity. We present data on the relationship between traffic self-similarity and network performance as captured by performance measures including packet loss rate, retransmission rate, and queueing delay. Increased self-similarity, as expected, results in degradation of performance. Queueing delay, in particular, exhibits a drastic increase with increasing self-similarity. Throughput-related measures such as packet loss and retransmission rate, however, increase only gradually with increasing traffic self-similarity as long as reliable, flow-controlled transport protocol is used.

On the Relationship Between the Generalized Equality Classifier and ART 2 Neural Networks

In this paper, we introduce the Generalized Equality Classifier (GEC) for use as an unsupervised clustering algorithm in categorizing analog data. GEC is based on a formal definition of inexact equality originally developed for voting in fault tolerant software applications. GEC is defined using a metric space framework. The only parameter in GEC is a scalar threshold which defines the approximate equality of two patterns. Here, we compare the characteristics of GEC to the ART2-A algorithm (Carpenter, Grossberg, and Rosen, 1991). In particular, we show that GEC with the Hamming distance performs the same optimization as ART2. Moreover, GEC has lower computational requirements than AR12 on serial machines.