Abstract. Service providers in this highly competitive market are demanded to find ways to attract new customers, retain existing customers, and pursue customers' loyalty. The quality of the service which has to deliver to the customers has been considered as a critical factor for the success of the service providers by a reason of its close connection to customer satisfaction. This paper aimed to assess the service quality of the service firms and identify what dimensions they have to prioritize to attain the customer satisfaction. SERVPERF model was employed to achieve the first objective while importance-performance analysis was utilized for the second objective. A case study was conducted in Ahmad Yani International Airport, Indonesia, to demonstrate the applicability of the method.

Abstract-There exist explicit pressures to the universities to integrate sustainability into their systems due to numerous declarations and commitments related to the need of sustainability in higher education. As a consequence, there are several frameworks for achieving campus sustainability. The objective of this research is to verify the adherence between the condition at Diponegoro University and the framework for achieving campus sustainability proposed by Alshuwaikat and Abubakar. A case study is conducted through observation, data and document collection, and interview with the university's stakeholders, professors, lecturers, and students of the university. It can be concluded that the university is partially adherence with the framework at the time this research was performed. Several recommendations are proposed to the university to be more sustainable.

--As competition increases, delivering better service becomes more important; it is not with the expception of PT. Telekomunikasi Indonesia, Tbk (PT TELKOM)

This study aims to demonstrate effectively application of the seven tools as one of the quality management tools to reduce product defects. A case study has been conducted in the production of white body at PT. XYZ, which is located in Semarang. The high percentage of defects is considered as one causes of not attaining the target of the company. Seven tools, which consist of check sheet, stratification, histogram, scatter diagram, control chart, Pareto chart, and cause-and-effect diagram, are used to analyze the causes of the defects. Based on data processing results, there are eight types of defects, namely: tobi, hage, burn back, crolling, saya boro, broken back stamp, hama kake, and nama kire. Recommendations for improvement have been proposed using 5W+1H analysis to improve the company's quality control performance and minimize product defects.

This study aims to cluster countries according to the logistics performance index (LPI) 2018 data. LPI is one of the indicators for measuring logistics sector performance based on a survey developed by the World Bank since 2007 and has been widely accepted throughout the world. There are 160 countries involved in organizing the 2018 edition of the LPI. It helps countries to understand their current position and develop strategies and policies to improve their performance in world trade. Three clustering algorithms (i.e., k-means, k-medoids, and clustering large applications) are used. To obtain the optimal number of clusters, the elbow method is used. According to the elbow method, the optimal cluster is three for those three clustering algorithms. The countries belong to the first cluster are considered the best performers, while countries in the third cluster are the worst performance in terms of logistics performance. This study is expected to give an insight into how to implement clustering algorithms into the real-world data set and how to interpret the results