In Korea, more than 80% of municipal wastewater treatment plants (WWTPs) with capacities of 500 m3·d−1 or more are capable of removing nitrogen from wastewater through biological nitrification and denitrification processes. Normally, these biological processes show excellent performance, but if a toxic chemical is present in the influent to a WWTP, the biological processes (especially, the nitrification process) may be affected and fail to function normally; nitrifying bacteria are known very vulnerable to toxic substances. Then, the toxic compound as well as the nitrogen in wastewater may be discharged into a receiving water body without any proper treatment. Moreover, it may take significant time for the process to return back its normal state. In this study, a DO- and pH-based strategy to identify potential nitrification inhibition was developed to detect early the inflow of toxic compounds to a biological nitrogen removal process. This strategy utilizes significant changes observed in the oxygen uptake rate and the pH profiles of the mixed liquor when the activity of nitrifying bacteria is inhibited. Using the strategy, the toxicity from test wastewater with 2.5 mg·L−1 Hg2+, 0.5 mg·L−1 allythiourea, or 0.25 mg·L−1 chloroform could be successfully detected.

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Recently, collaborations through MCS use in team projects are frequently conducted. This study developed a research model to examine the impact of collaboration through MCS on project performance. Team commitment and team trust regarded as the key drivers of enhancing project performance. Moreover, we also investigated the effect of usefulness of MCS on project performance. We posit ubiquity, polychronic use, and ease of use as the key antecedents of usefulness of MCS. The proposed theoretical framework was tested by using survey data collected from 116 university students who have rich experience with collaboration through MCS. PLS was employed for the analysis of the data. The analysis results showed that team trust significantly influences team commitment and project performance, respectively. However, usefulness of MCS is not significantly related to team commitment, while it play a prominent role in enhancing project performance. The results reveals that ease of use has a significant effect on usefulness of MCS, whereas ubiquity and polychronic use are not significantly related to it. From theoretical and practical perspective, this paper can provide in-depth knowledge of the effects of collaboration via MCS on project performance.

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Several game developers or publishers adopt open innovation strategies to reduce R&D costs and increase user loyalty about their games. User communities play an important role in increasing users' interests in the game because they can share game information and skills in user communities. In this regard, this study explored key antecedents of game user participation intention in user community. We developed a research model by integrating perceived risk into theory of planned action. The theoretical model was tested by using survey data collected from 110 "Suddenattack" game users. Partial least squares (PLS) was utilized to analysis the research model. The findings of this study indicate that both perceived usefulness and perceived enjoyment play an important role in forming attitude toward community. However, contrast to our expectations, perceived risk has no signifiant effect on perceived usefulness, perceived enjoyment, attitude toward community and participation intention. While attention toward community significantly influences community participation intention, social norms are not significantly related to it. The analysis results help game developers or publishers establish effective strategies and policies to increase user participation intention in user community.