Sand Penetration: A Near Nose Investigation of a Sand Penetration Event

This paper presents experimental and computational results of a long-rod penetrating dry granular sand at velocities near 100 m/s. The objective of this work is to develop a fundamental understanding of the formation and transmission of dynamic force chains, and the motion and fracture of the individual sand grains as the projectile passes. This is accomplished by launching a projectile along a view window, backed by sand, in order to directly view and photograph the projectile/sand interactions. Within the sand system, a two-wave structure was observed, composed of a compaction wave (bow shock) that detaches from the dart and moves through the sand at a wave speed near 100 m/s and a damage wave, which remains near the leading edge of the dart. The compaction wave removes porosity and the damage wave fractures grains in the region near the projectile nose. Grain fracture is not observed at dart speeds below 35 m/s. In addition the axial strain to failure of individual sand grains was measured in a quasi-static configuration. These results were used in conjunction with a simple analytic force balance model to predict the depth of penetration. The analytic results compare favourably with experiments until the dart slows below 35 m/s

The process of cross-sector collaboration for the health of local and regional populations.:What works, why and in which context?

Het Nederlandse zorgsysteem staat onder druk. Het wordt steeds moeilijker om kwalitatief goede zorg te leveren die ook betaalbaar en toegankelijk blijft. Daarbij is het huidige gezondheidssysteem met name ingericht rondom zorg en niet rondom gezondheid. Dit vraag om een transformatie van het zorglandschap, waarbij domeinoverstijgend samenwerken nodig is om zorg te voorkomen, vervangen en verplaatsen. Alleen hoe doe je dat? Samenwerking kan namelijk ontzettend complex zijn, en is afhankelijk van vele factoren. Denk aan onderlinge relaties, de belangen van de eigen organisatie en de invloed van de omgeving. In dit proefschrift is, door middel van kwalitatief onderzoek, onderzocht welke strategieën je kan inzetten in lokale en regionale samenwerkingsverbanden om succesvol samen te werken voor de gezondheid van de inwoners. Met strategieën bedoelen we bewust wel of niet handelen om het samenwerkingsproces te beïnvloeden. Door onderzoek te doen met de realistische evaluatie benadering is inzicht verkregen in hoe strategieën in een bepaalde context werken, en waarom. Hierbij zien we dat er geen one-size-fits-all strategie is voor samenwerking, maar dat de keuze van de juiste strategie erg afhangt van de context van de samenwerking. Zo verandert het gebruik van strategieën gedurende het samenwerkingsproces. We leren dus dat, wanneer je het samenwerkingsproces wil optimaliseren, het belangrijk is om regelmatig te reflecteren of je nog wel de goede strategieën inzet. Uit het onderzoek blijkt bovendien dat er een verschil is in strategieën voor optimaliseren van de samenwerking binnen de huidige systemen, en voor het daadwerkelijk samen transformeren. Wanneer men namelijk samen werkt aan een transformatie van het zorgsysteem zien we dat er niet alleen wordt ingezet op het verbeteren van de samenwerking tussen de partners. Er wordt ook ingezet op het aanpassen van de structuren om de samenwerking heen. Denk bijvoorbeeld aan het werken aan een gezamenlijke data-infrastructuur, passende bekostiging of inwonerparticipatie. Er zijn voor het samenwerken aan deze transformatiebeweging van het zorgsysteem acht leidende principes geïdentificeerd die belangrijk zijn voor het samenwerkingsproces. Dit zijn: het creëren en behouden van draagvlak, het inzetten op vertrouwen en onderling begrip, het vormgeven van randvoorwaarden voor gezamenlijke verantwoording, inzet op politiek draagvlak, het vormgeven van een passende data-infrastructuur en verbetercyclus, het vormgeven van financiële prikkels die aansluiten bij de gezamenlijke doelen, inzet op inwonerparticipatie en het vormgeven van passende bestuurlijke representatie en leiderschap. Belangrijk hierbij is dat inzet op al deze principes belangrijk is. We zagen namelijk dat het niet inzetten op bepaalde principes, bijvoorbeeld het werken aan een gezamenlijke data-infrastructuur, later in het samenwerkingsproces voor vertraging zorgde. Domeinoverstijgend samenwerken aan transformatie vraagt daarnaast om een lerende houding omdat veel nog onzeker is. Uit ons onderzoek blijkt echter dat er nog niet optimaal wordt ingezet op het leren op het niveau van het samenwerkingsverband. Er is leiderschap nodig wat zich richt op de transformatie en waarbij het belang van een gezamenlijk leerproces wordt gezien. Ook is er expertise nodig voor het juiste gebruik van data en kennis om hiervan te kunnen leren. Bovendien is een faciliterende omgeving nodig voor het leren. In dit proefschrift worden aanbevelingen gedaan om in te zetten op het organiseren van dezeleeromgeving, zowel vanuit beleid als vanuit de praktijk. Hierbij wordt een verbinding tussen beiden aangeraden. Bovendien is het van belang om zowel vanuit beleid als praktijk helder te hebben met welke focus samengewerkt wordt aan gezondheid. Is dit bijvoorbeeld gericht op het optimaliseren binnen huidige systemen, of werkt men samen aan een transformatie van het zorgsysteem._The Dutch healthcare system is under rising pressure. It is becoming increasingly difficult to provide high quality care that also remains affordable and accessible. In addition, the current health care system is primarily structured around care rather than health. This calls for a transformation of the healthcare landscape, where cross-sector collaboration is used to prevent, replace and relocate care. Only how do you do that? After all, collaboration can be incredibly complex and depends on many factors. Consider interrelationships, the interests of one's own organization and the influence of the environment.This dissertation examined what strategies you can use in local and regional collaborations to successfully collaborate for the health of residents. By strategies, we mean consciously acting or not acting to influence the collaborative process. By conducting interviews using the realist evaluation approach, insight was gained into how strategies work in a given context, and why.Here we see that there is no one-size-fits-all strategy for collaboration, but that the choice of the right strategy depends very much on the context of the collaboration. Also, the use of strategies changes during the collaboration process. So we learned that when you want to optimize the collaboration process, it is important to regularly reflect on whether you are still using the right strategies.Moreover, the study shows that there is a difference in strategies for optimizing collaboration within current systems, and for actually transforming together. Indeed, when working together to transform the healthcare system, we see that efforts are made not only to optimize collaboration between partners. Efforts are also made to adapt the structures around the collaboration. Consider, for example, working on a joint data infrastructure, appropriate funding or citizen participation.Eight guiding principles have been identified for transforming healthcare systems that are important to the collaborative process. These are: 1. shared commitment for developing towards a health system, 2. mutual understanding and trust; 3. accountability; 4. aligning politics and policy; 5. financial incentives; 6. a learning cycle based on a data-infrastructure; 7. community input andinvolvement; and 8. stakeholder representation and leadership. What is key here is that commitment to all of these principles is important. We saw that not committing to certain principles, for example working on a joint data infrastructure, caused delays later in the cooperation process.Cross-sector collaboration on transformation additionally requires a learning attitude because much is still uncertain. However, our research shows that learning at the collaborative level is not yet optimally organized. Leadership that focuses on transformation and sees the importance of a joint learning process is needed. Expertise is also needed for the proper use of data and knowledge in order to learn from it. Finally, we also need an enabling environment for learning.This dissertation makes recommendations to both policy and practice to engage in organizing thislearning environment. A connection between the two is recommended. Moreover, it is important to be clear from the start, for both policy and practice, with which focus one collaborates for health. Is this, for example, aimed at optimizing within current systems, or are we working together for transformation of the healthcare system

Incompressible viscous flow near the leading edge of a flat plate admitting slip

The shear stress at the leading edge, calculated on basis of the Navier-Stokes equations and the no-slip boundary condition, approaches infinity. However, taking into account the mean free path of the molecules, which implies admitting a certain slip, the shear stress becomes inversely proportional to the square root of the Knudsen number κ if κ→0. κ is defined as the ratio between the mean free path and the viscous length. The new boundary condition modifies the shear stress only within the Knudsen region of which the size is of the order of 3 to 4 times the mean free path.

The EEAS' diplomatic dreams and the reality of European and international law

The aim of this paper is to confront the diplomatic ambitions of the European External Action Service (EEAS) with the reality of EU and international law. Treaty provisions as well as policy documents and statements of EU officials reveal a development in the direction of a strengthened role for the EU itself as a diplomatic actor. The findings underline a continued tension between the EU’s diplomatic ambitions and EU and international law as it stands. In relation to the EU’s internal structures, there is no doubt that in the new EU institutional landscape dividing lines remain firmly in place. Yet, the working arrangements do point to ‘holistic’ thinking implying cooperation and reciprocity. In addition the paper argues that the EU’s ambitions sit uncomfortably with traditional state-centred international diplomatic law. Extensive diplomatic activity of the EU depends on the acceptance by the willingness of third states to accept the EU as a diplomatic actor

Teachers' attitudes towards (the alignment between) grammar in the L1 language curricula of primary and secondary education

In recent years, Dutch grammar education (L1) in Flemish primary (PE) as well as secondary education (SE) has been the subject of much debate. Research into the grammatical knowledge of students in SE (n=359) suggests that this expertise falls short of the final attainment targets. Additional research now tries to pinpoint the reasons underlying this trend, focusing on the attitude of teachers, which is an 'understudied' aspect of language teaching. This research, centring around L1 teachers of Dutch in SE (n=255) and PE (n=318), applies two methodological instruments: a Likert-scale attitude questionnaire and teacher interviews. Teacher variables include gender, years of classroom experience, school type and school grade. The research in SE reveals that, in general, (1) teachers' attitudes correlate with students' performances, in that 52% of the teachers are rather pessimistic about their students' level of grammatical proficiency, (2) 76% of them believe that the general level of language proficiency has dropped in recent years and (3) 47% of the teachers are of the opinion that grammar education is a poor relation in the Dutch language curriculum, especially with a view to learning foreign languages. The second study conducted in PE shows that, in general, (1) 75% of the teachers think that their students' general level of language proficiency has declined, (2) 71% of them want to spend more time on grammar than the curriculum prescribes, (3) 80% of the teachers believe that Dutch grammar in PE is insufficiently aligned with Dutch grammar in SE and (4) 81% of them are of the opinion that Dutch grammar instruction is out of step with foreign language grammar instruction. One of the major problems this attitude study reveals, concerns the poor alignment between grammar in the Dutch language curricula of PE and SE. The majority (62%) of the teachers in PE, for instance, are completely oblivious to Dutch language expectations in the 1st year of SE. Additionally, 70% of them feel there is little, if any, interaction between teachers in PE and SE about the instruction of Dutch. Supporting this statement, the majority (63%) of the teachers in SE share this opinion. This perceived problematic alignment between grammar in the Dutch language curricula of PE and SE may have major implications for (future) curriculum design

Leaders Address Inequity Through a Framework of International-Mindedness

This paper offers school leaders and scholar practitioners twin frameworks of international-mindedness and cultural proficiency as a means to addressing persistent education gaps. International-mindedness is a global perspective framework and cultural proficiency is an equity-focused framework. These complementary frameworks are grounded in the educational policies and practices found in the International Baccalaureate (IB) programs. In an era focused on closing achievement gaps, students from diverse backgrounds have opportunities to engage in topics and dispositions in IB that connect to their prior knowledge and experiences through a new lens and global perspective. Once viewed as an elitist high school program, the IB is now offered in an increasing number of public schools as a school wide initiative to support the needs of all students, including language learners and students from low socio-economic backgrounds. Teachers and school leaders in IB schools teach human similarities and differences through a local and global perspective to better prepare and engage all students in the knowledge and skills they will need in the changing world of the 21st century. To realize this expanded goal of access and achievement for all students, school leaders and educators must also understand the complementary conceptual frameworks of cultural proficiency and international-mindedness. The authors recommend that by aligning the frameworks of international-mindedness and cultural proficiency, students of all demographic groups and their teachers become aware of a wider world, respect and value diversity, understand how the world works, participate both locally and globally, and may be motivated to take action as engaged citizens