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This paper aims to analyze the corrosion and corrosion inhibition of N80 in 10 per cent HCl + 8 per cent fluoroboric acid (HBF₄) solution for acidizing operation.

The corrosion rate, kinetic parameters (Ea, A) and thermodynamic parameters (ΔH, ΔS) of N80 steel in fresh acid and spent acid, 10 per cent HCl + 8 per cent HBF₄, 10 per cent HCl and 8 per cent HBF₄ solutions were calculated through immersion tests. The corrosion and inhibition properties were studied through X-ray diffraction and electrochemical measurements. The corrosion morphology of the corrosion product was examined by scanning electron microscopy (SEM).

The results demonstrated that the spent acid was the main cause of acidification corrosion, and the HBF₄ would cause serious corrosion to N80 steel. The results showed that the N80 steel was more seriously corroded in the spent acid than in fresh acid, and the hydrolysis of HBF₄ accelerates the dissolution process of N80 steel anode to control the corrosion reaction. The results showed that the acidification will definitely cause serious corrosion to the oil tube; therefore, necessary anti-corrosion measures must be taken in the acidification process.

The results showed that acidizing the formation with 10 per cent HCl + 8 per cent HBF₄ will definitely cause serious corrosion to the oil tube, especially when the spent acid flows back. Therefore, necessary anti-corrosion measures must be taken in the acidification process, especially in the spent acid flowback stage.

This paper aims to study the corresponding optimal service strategies and pricing in the styled non-preemptive M/M/1 service systems from different objectives, which consider both heterogeneous waiting costs of customers and service values in customer segmentation.

In this paper, the authors consider two service situations where customers cannot leave the service system (i.e. monopoly service system) and customers can leave the service system freely (i.e. non-monopoly service system), respectively. The authors study the following four different perspectives that are revenue, social welfare, social cost and utility of customers. The authors first build up a new model, then propose the related objective functions. Further, the authors optimize the corresponding functions and achieve the optimal results. Later, the authors propose the corresponding optimal strategies. Finally, the authors use a practical numerical case to verify the proposed results.

The results of this paper indicates that the service provider should adopt classification services to gain the maximum revenue, the maximum social welfare and the minimum social costs by charging a priority fee in above two service systems. However, the service provider should cancel customer classification and keep regular customer only to obtain maximum utility. In the monopoly service system, both the optimal proportion priority customers and the revenue decrease with the increasing of the service rate, while in a non-monopoly service system, both of them are increasing with the service rate improving.

This paper first considers both heterogeneity of service values and waiting costs in queuing system, then the author set up a new model based on this assumption. Moreover, the authors draw the corresponding management insights based on the optimal results, which were unavailable before.

The purpose of this paper is to propose and test a conceptual model that explains racially/ethnically differential confidence in order institutions through a mediating mechanism of perception of discrimination.

This study relies on a nationally representative sample of 1,001 respondents and path analysis to test the relationships between race/ethnicity, multiple mediating factors, and confidence in order institutions.

Both African and Latino Americans reported significantly lower levels of confidence compared to White Americans. People who have stronger senses of being discriminated against, regardless of their races, have reduced confidence. A range of other cognitive/evaluative variables have promoted or inhibited people’s confidence in order institutions.

This study relies on cross-sectional data which preclude definite inferences regarding causal relationships among the variables. Some measures are limited due to constraint of data.

To lessen discrimination, both actual and perceived, officials from order institutions should act fairly and impartially, recognize citizen rights, and treat people with respect and dignity. In addition, comprehensive measures involving interventions throughout the entire criminal justice system to reduce racial inequalities should be in place.

Equal protection and application of the law by order institutions are imperative, so are social policies that aim to close the structural gaps among all races and ethnicities.

This paper takes an innovative effort of incorporating the currently dominant group position perspective and the injustice perspective into an integrated account of the process by which race and ethnicity affect the perception of discrimination, which, in turn, links to confidence in order institutions.

This paper comparatively assesses the connections between individual demographic traits, occupational characteristics, and organizational factors and officers' attitudes toward important groups in China and Taiwan.

Survey data used in this study were collected from 722 police officers from mainland China and 531 officers from Taiwan. Multivariate regression analyses were conducted to assess the correlates of police attitudes toward peers, supervisors, and citizens.

The Chinese and Taiwanese officers do not differ in their trust in peers, but the Chinese officers hold significantly more positive views on the trustworthiness of supervisors and citizens compared to the Taiwanese officers. Supervisor justice and organizational identification are significant predictors of officers' attitudes toward all three groups in both countries.

A major limitation revolves around the inability to test and explain exactly why findings from the two groups vary in their ways. Future research should include specific social, political, and cultural predictors.

This study represents one of the few studies that compare police attitudes toward important groups of peers, supervisors, and citizens across nations/cultures.

The purpose of this paper is to assesses whether supervisor justice is linked to COVID-19 negative and positive impacts directly and indirectly through the mechanisms of stress and resiliency among auxiliary police in China.

This study utilized survey data from more than 300 auxiliary police in a large Chinese provincial capital city in 2020. Structural equation modeling was conducted to analyze the direct and indirect relationships between supervisor justice and COIVD-19 impacts.

Results indicate that supervisor justice connects to COVID-19 negative impacts indirectly through stress. Supervisor justice is also indirectly related to positive impact through resiliency.

The findings' generalizability is limited due to using a nonrandom sample of officers. Officers' emotional states in the forms of stress and resiliency are important in mediating the association between supervisory justice and COVID-19 impacts.

The present study represents one of the first attempts to empirically investigate the occupational experiences of a vital group of frontline workers in Chinese policing. This study also generates evidence to support the importance of officers' emotional conditions in reducing negative COVID-19 impacts in an authoritarian country.

The purpose of this paper is to examine the effects of media exposure and political party orientation on public satisfaction with and trust in the police in Taiwan.

Survey data were collected from more than 2,000 respondents in three large metropolises and two rural counties in Taiwan in 2011. Multivariate regression was used to assess the effects of media exposure and political party affiliation on public satisfaction with and trust in the police, controlling for crime experience, neighborhood conditions, background characteristics, and locality.

Taiwanese who were exposed to media reports of police misconduct and believed in the authenticity of such reports were more likely to have lower levels of satisfaction with national police and trust in the police. Though it varied somewhat by whether it was satisfaction with national or local police, the Taiwanese respondents who identified themselves as supporters of the opposition party, or politically neutral, showed lower levels of satisfaction with and trust in the police than supporters for the ruling party. Respondents who shared the same political party orientation expressed higher levels of satisfaction with local police.

The measures of media influence, while classic and straightforward, were relatively simple and future research should not only quantify the links between media use and public trust, but also develop a qualitative cultural understanding of the communicative roles that the media play in shaping public perceptions of the police. In addition, while this study relied on a scientific sampling procedure, the sample cannot completely represent the general population in Taiwan.

It is important for police departments to cultivate good relations with the news media and to adopt a balanced role between law enforcers who are capable of curbing crime and reducing fear of crime, and moral guardians who are willing to uphold community social cohesion and value structures.

Despite a growing number of studies on public assessments in the police in Taiwan, empirical research on the impact of media and political orientation on satisfaction with and trust in the police remains very limited. This study represents one of the first attempts to assess factors related to media and political party orientation in Taiwan.

The purpose of this paper is to examine Chinese police officers’ general support for police intervention into domestic violence, emphasizing adequate protection of the victims, and specific support for utilizing arrests to deal with the offenders.

This study relies on survey data collected from 1,064 police officers who worked in multiple areas in two provinces of China between June and July of 2019. OLS models were used to test whether organizational variables are significant predictors of officer attitudes toward domestic violence intervention.

Both agency endorsement and supervisory support are positively related to officers’ favorable attitudes toward police intervention into domestic violence and using arrests to handle offenders. The amount of training received from the agency on the recently promulgated Anti-Domestic Violence Law, however, has a negative influence on officer support for general intervention into domestic violence and no influence on officer attitudes toward arrests.

This study represents one of the first attempts to investigate the connections between organizational and managerial factors and Chinese officers’ support for both general and specific interventions into domestic violence. It contributes to the current literature that only included police cadets in the analysis of Chinese police attitudes toward domestic violence despite the fundamental differences between cadets and active-duty officers.

The purpose of this paper is to develop a trading and pricing method of expansion option (EO) model to solve expansion problems of build-operate-transfer (BOT) freeway project.

This paper proposes an ex ante mechanism through trading the EO to avoid the transaction costs. By editing the paths generated from binomial option pricing model, this paper establishes an American real option binomial lattice model and evaluates the value of EO. Data are collected from Liaoning province in China and the model is practiced in the context of a BOT freeway in Liaoning province.

Supported by empirical evidence, this study finds out that there exists a minimum price at which the government can sell the EO and a maximum price that the private sector is willing to pay. When the minimum price is negative, the government should transfer the EO to the private sector free of charge to avoid the transaction costs. Otherwise, the government should sell the EO at a reasonable price to protect public interests.

The study can be used for the government to reducing the transaction costs. By using the trading EO model, the government can sell its share of the EO to the private sector to manage its resources efficiently.

This paper builds a trading EO model to solve expansion problems instead of renegotiations. In addition to reducing the transaction costs for the whole society, trading EO can also raise the respective payoffs of both public and private sectors. An EO trading framework and algorithm is further developed. It realized an American option model, making the owner can exercise the option whenever he wants. Thus, the whole model is adapted to best fit BOT highway practice.