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The purpose of this paper is to test the wear behavior of a carbon steel surface after cladding by gas tungsten arc welding (GTAW) method to enhance wear resistance.

The microstructures, chemical compositions, and wear characteristics of cladded surfaces were analyzed by scanning electron microscopy (SEM), and energy dispersive X‐ray spectroscopy (EDX). A rotating‐type tribometer was used to evaluate the wear characteristics of cladded specimens under dry sliding conditions at room temperature. The dry sliding wear resistance of the coatings was tested as a function of applied load and sliding time, and wear mechanisms were elucidated by analyzing wear surfaces.

The experimental results revealed an excellent metallurgical bond between the composite coating and substrate. The coating was uniform, continuous, and almost defect‐free, and particles were evenly distributed throughout the cladding layer. Hardness was increased from 200 HV in the substrate to 650‐800 HV in the modified layer due to the presence of the hard TiC phase. The excellent wear resistance and very low load sensitivity observed in the dry sliding wear test of the intermetallic matrix composite coating were due to the high hardness of TiC and the strong atomic bonds of the intermetallic matrix.

The experiments in this study confirm that, by reducing friction and anti‐wear, the cladding layer prepared using the proposed methods can prolong machinery operating life.

Resource discovery in peer‐to‐peer (P2P) systems have been extensively studied. Unfortunately, most of the systems studied are not designed to take advantage of the heterogeneity in peer nodes. In this paper, we propose a novel P2P overlay called RATTAN, which serves as an underlay of a Gnutella‐like network. RATTAN exploits the heterogeneity of peer nodes by structuring capable nodes as the core of the overlay. Using a tree‐like structure, RATTAN can maximize the search scope with a minimal number of query messages. We evaluate RATTAN with simulation. The experiments show the following interesting results. First, RATTAN is robust by exploiting redundant overlay links. Second, the maximum bandwidth demand for processing the protocol of a single RATTAN overlay is nearly 1M bits/sec. However, around 80% of the nodes merely take 66 bits/sec. One implication is that we can use a small number of relatively capable peers (e.g., stable machines with a 100M bits/sec network interface) to process the 1M bits/sec protocol overhead and serve other peers that only need to spend 66 bits/sec for processing protocol overhead.

The purpose of this paper was to examine the predictive power of each dimension of public service motivation (PSM) on job performance (JP) in a Taiwan sample.

The present study adopted a cross-sectional approach using a large-scale questionnaire survey in Taiwan (N=2,239). Participants from six utility sectors in two infrastructure-relevant ministries (Ministry of Transportation and Communications (MOTC) and Ministry of Economic Affairs (MOEA)), with heterogeneous sectors, were recruited, including representatives of the Taiwan Railways Administration (TRA), Chunghwa Post (CHP), Taiwan Power Company (TPC), CPC Corporation, Taiwan (CPC), Taiwan Sugar Corporation (TSC), and Taiwan Water Supply Corporation (TWSC). The sample consisted of 2,239 public employees from six public utilities.

Although the results suggest that the PSM observed in western society also exists in the Taiwanese public utilities context, the self-sacrifice (SS) and the compassion (COM) dimensions were unconfirmed. The research found that for all utilities SS was significantly negatively correlated with JP, while attraction to public policy making (APP) and commitment to public interests (CPI) were significantly positively correlated with performance. Moreover, CPI was the only dimension of PSM that consistently predicted employees’ JP across utilities.

First, the authors tested the theory using a limited sample of public employees from Taiwanese public utilities. The cross-sectional design does not offer a clear cause-and-effect relationship as examined in the current study. Data collected only from public utilities in Taiwanese sample may cause concerns for the generalisability of the present findings to other settings. Second, the data do not address the timevariant effects of PSM. Third, the current empirical findings are based on Taiwan’s public utilities. The observations should be interpreted with caution. A broader sample of employees would make the empirical results more generalisable beyond the country-specific findings.

Researchers should unpack the PSM and JP concepts and strategically explore subdimensional relationships, but these results offer new insights into the influence of such subdimensions on the link between PSM and JP. PSM in public utilities has great potential to enhance JP through high levels of CPI and APP. Furthermore, public utilities management staff should acknowledge the value of PSM for JP and, if applicable, praise it with substantial rewards.

The relationship of the PSM to JP in public utilities is much less studied, especially in Asian countries. Moreover, no study on employees in public utilities has previously used a Taiwan sample.