Persuasion, especially in written form, has been acknowledged by scholars as difficult. Success in its attempt requires complex use of, among others, pragmatics. Persuasive texts have therefore been highly researched using the speech act theory. However, a research gap existed for a study of illocutionary acts in newspaper opinion articles. To fill the gap, the current study did a qualitative textual analysis on 10 U.S. online newspaper opinion articles that talk about climate change. The analysis was conducted to discover types of illocutionary acts and persuasive strategies the writers use to successfully persuade readers. It was then found that the writers predominantly performed assertives. The second most frequently used were directives. The most preferred subtypes under these categories were, among others, informing, urging, assuring, and demanding. These preferences further revealed the writers' persuasive strategies. The strategies were as follows: being highly implicit, being occasionally explicit, giving more information about the issue, conveying certainty and uncertainty, arousing fear, also creating a sense of urgency. These acts and strategies, according to existing theories, could increase the texts' persuasiveness. Hence, this study establishes that when used in persuasive texts, the previously mentioned illocutionary acts and strategies can help writers to attain persuasion.

The aims of this study are to capture the current state of Design For Six Sigma (DFSS) and to systematically review literature on practices of DFSS published between 2006 and 2018. The questions are: what is DFSS, the application, the essential ability, and limitations, the main trending topics of DFSS? All these questions are used to guide the search for journal in databases and other sources. Then, all relevant literature was reviewed and analysed. There were 18 topics found to be included in the review. The authors proposed two different issues relevant to DFSS. All these papers were interpreted by tools and techniques, such as the implementations of DFSS, its uses, applications, and how it is linked to other disciplines. Data was collected and clustered by year, topic, and keywords in DFSS to be used in configurations and progress improvement and innovation of DFSS. This review found four definitions of DFSS, eight applications and uses of DFSS, three challenges and obstacles in using DFSS, and two future direction of research of DFSS based on its fast-changing product design.