As the world continues to urbanize, it is necessary to identify and implement new urban development models and strategies in order to meet the challenges of sustainable development. As cities continue to face challenges in becoming fully circular, the need to establish a framework to measure the circular economy in urban areas grows. Many definitions for circular cities have been developed and addressed in recent years, as have numerous indicators. To make the transition to a circular city, we must integrate the findings and develop a general definition and measurement framework. This article aims at outlining a framework for circular cities indicators based on their key characteristics, as well providing directions for fostering circularity at the city level. To accomplish this goal, we conducted a systematic review and analyzed key papers published in the field of circular economy to determine how circular cities are measured. Choosing the right indicators to use for developing, monitoring, and evaluating circular cities is a difficult task for urban policymakers, managers, and planners. This highlights the significance of standardized frameworks for urban indicators. As a result, the authors propose a framework and highlight some key points about circular cities and smart urban metabolism.

The objective of this paper is to analyze the extent to which the system of indicators that is used in the Monitoring Framework for the transition to the circular economy (CE) is efficient and relevant in their contribution to the sustainable development of European communities. The fundaments of the transition framework and the main characteristics of the circularity indicators are presented. A critical review was performed in order to fulfill the objective of analyzing the current indicators. It is concluded that the indicators in the current framework are (as a selection from a very broad range of indicators theoretically proposed and with estimated practical applicability) limited from the perspective of circularity only to waste generation and recycling processes containing recyclable materials, without including important circularity indicators related to the prolonging and extending the life cycle of products and materials. This paper proposes and defines such an indicator, based on the consideration of the fundamental scalars describing economy, mass, energy, time, and value, respectively. The indicator is described and its applicability in all the phases of the economy is estimated.

Literature so far illustrates different approaches to achieving circular economy (CE). It is increasingly important that every industry explores opportunities to transitioning towards CE doing it through process streamlining or via uses of technology to transform/exchange the resources. We recognize the difficulties faced by researchers in consolidating key aspects to CE, due to still fragmented knowledge base. To clearly identify these aspects is somewhat difficult due to the fragmented knowledge over applications of circular economy. However, any holistic approach is possible by considering the performance of the growth (in our temporal visible world) and that of innovation and creation as a result of the introspection of the temporal invisible world (thought and inspiration), in terms of three fundamental scalars in nature, mass, energy, and time transformed by natural action and human action, in order to define the circularity for any group, category, and type of product. We consider that the effect of any action should be evaluated by determining the most probable results and the dynamic of any process (using statistics), by considering the transformation of the three fundamental scalars. This article presents a consonant approach of the economy, aiming to optimize the intervention of humans in the natural environment and its performance and having the scope of the integration of the human actions in the natural cycles, to secure sustainability.

The paper aims to emphasize the contribution that manufacturing industry can have to meet the Circular Economy (CE) scope related to the use of resources. First, we presented the CE concept and the framework in Europe, the monitoring framework and also, we noted some aspects of manufacturing industry related to CE. Then, we performed an analysis of the secondary raw material data, which is one of the representative indicators of CE, in order to see the state of circular economy related to the resources in European Union Member States. The results showed that the resource circularity is lowest in Europe, the states which can be remarked are Germany, Netherlands, and Belgium. Highlighting these aspects, some conclusions were formulated, the most evident is that the manufacturing industry has a very important role on the CE transition, consisting in the resources fact implicated. The manufacturing industry can choose to use secondary raw materials instead of virgin raw materials, can improve resource efficiency through the technologies used in production processes and can address the circularity of a product, being an important CE actor.

Abstract. This article presents the concept of open innovation in IT brands, an industry that is always evolving. We will present the results of a preliminary study regarding the benefits of open innovation on ClujNapoca IT brands, the evolution of the number of employees from large companies in the industry and the future direction of research. The sample of the study contains 37 firms selected from a total of 1,490 companies registered in Cluj-Napoca.