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Summary. This paper describes new theoretical results for predicting the buckling behavior of pipe in horizontal holes. Pipe buckling in horizontal holes occurs initially in a sinusoidal mode along the low side of the hole; at higher axial compression a helix is formed. Equations are given for computing the forces required to initiate these different buckling modes. Simple experimental laboratory results confirm the theory. Results presented in this paper apply to friction modeling of buckled tubulars to help predict when pipe can be forced to move along a long section of a horizontal well. Introduction Since 1950, many analyses have been performed on the mechanics of pipe in oil and gas wells. Lubinski et al. defined the helical buckling behavior of pipes in vertical wells. However, the postbuckling behavior of pipe in horizontal wells is different from that in nearly vertical wells. Knowledge of the configuration of buckled tubulars is important to prevent costly failures and to predict whether a tool can be forced along a horizontal well. This paper provides methods to analyze these problems. Two modes of buckling can occur for tubulars in horizontal or steeply inclined wells: helical and sinusoidal (Fig. 1). The axial compressive force required to buckle the pipe into a sinusoidal configuration depends on pipe stiffness and weight and on hole size in a manner similar to a beam on an elastic foundation. As axial force is increased, the buckling mode changes from sinusoidal to helical. Model experiments confirm the results of the analyses.

Advances in the networked features of information and communication technologies hold the promise of enhancing integrated citizen-centric information and services. However, few governments to date have implemented an integrated citizen service information system, which is needed to fulfill that promise. This study aims to investigate the organizational determinants of the level of integration and use of a citizen service information system. It draws from the literatures on diffusion and adoption of innovation, technology acceptance and use, information systems implementation, and information technology (IT) and public administration. The primary sources of data are from International City/County Management Association (ICMA) data on citizen service systems and Electronic government (e-government) surveys. Ordered logit is the primary data analysis technique used. The study findings suggest the importance of getting citizen feedback in the move toward a more integrated citizen service information system. Strong organizational commitment to citizen services further plays a significant role in the more sophisticated use of such a system. Overall, however, management capacity and technical capacity do not register a significant relationship with a more sophisticated and extensively used system.

This exploratory study examines the effects of nondemographic characteristics on the adoption of e-government services in the United States combining two main theoretical perspectives: diffusion of innovations and the technology acceptance model. The results of a national survey suggest that nondemographic audience characteristics influence e-government adoption. The study adds to previous research in the area by identifying several sociopsychological characteristics that play a role in the adoption process: perceived usefulness, perceived uncertainty, and civic mindedness. The study also ascertains the influence of interpersonal communication and mass media channels on e-government adoption. Theoretical implications for future researchers and policy implications for producers of governmental web sites are discussed.