The international legitimacy of overseas interests protection mechanisms is related not only to whether protective actions can gain the support of host countries, but also to the reputation of the home country. Legitimacy in this context refers to the level of adherence to the conception of international justice instead of specific rules. The conception of international justice is characterized by temporality, relativity, and constructivity. Temporality refers that the conception of international justice changes along with the development of time. Relativity refers to the heterogeneous conceptions of justice and the international community's different expectations for different countries on the legitimacy of overseas behaviors. Constructivity means that great powers always play a significant role in the construction of the conceptions of international justice. In the construction of the international legitimacy of overseas interests protection mechanisms, China should fully appreciate and respond to all the aforementioned properties. First, China's protection mechanisms should reflect the values of the time in order to attain moral force, fill the gap between its conception of justice and that of the host country, and choose standards that match its international identity and the amount of expected benefits when interpreting legitimacy. Besides, China's endeavor should not be restricted to the semantic interpretation of legal texts.  Efforts should be made to theorize practical experience as well as to reshape the conception of international justice.

When considering China‘s role in promoting contemporary world order, we should take seriously the positive aspects of ancient Chinese

world system. Relevant studies have shown that the tributary system makes a peaceful world order, and it, in the analytical sense,

actually functions as a substitute for the suppressive hegemony model in international relations. Some constituent elements of the

tributary system are still valuable, for instance, attractiveness of civilization, standards formulating of legitimacy, principle of

non-aggression and voluntariness, political order promoted and sustained by economic power. Modern international system, like ancient

tributary system, also bears characteristics of hierarchical power, economic and security dependence, however, it does not imply

contradiction with principles of sovereign equality.

Currently, analyses on motivations of Vietnams maritime power development after the cold war are not comprehensive, which should be fully explained by the combination of two factors: cognition and implementation. At the cognitive level, the historical memory between China and Vietnam has strengthened the Vietnamese cognition of threat, pushing Vietnam to exercise restraints upon China in resorting to the expansion of sea power. Based on incentives in execution, Vietnamese maritime forces can play a deterrent role in law enforcement conflicts, crises or limited armed conflicts, with the aim to confront China‘s protection of maritime rights in the South China Sea. At the same time, Vietnam’s maritime power development is also inspired by the international landscape. As a result of the support of the United States and China‘s restraint policy, the development of Vietnams maritime power gains positive feedback of geopolitical environment, and avoids negative feedback in economic development. Therefore, the aforementioned motivations provide necessary

conditions for the expansion of Vietnam’s maritime power.

Since coming into power, the Duterte administration has actively adjusted its policy on the South China Sea. It is the combined effect of various factors, both internal and external environment, which rooted in the pragmatic and rational choice to realize the maximization of national interests. The Duterte administration still faces many constraints on implementing and advancing the current policy on the South China Sea, mainly including the domestic political pressure, the diplomatic pressure to seek a balance among major powers, and the pragmatic attitude towards the result of the South China Sea arbitration. With regard to the prospect of Duterte administration'policy on the South China Sea, it is closely related to the trend of Philippine domestic politics, the trend of US-Philippines relations and Japan-Philippines relations, as well as the trilateral interaction among China, the Philippines and the US. Therefore, China needs to pay close attention to, and carefully assess the trend of relevant situations in order to make a plan in time.

As the treasure repository for mankind, the largest transportation corridor, as well as the strategic buffer zone of the coastal states, the ocean plays a significant role in the development of human society. Recent research on the ocean mainly focuses on comprehensive marine strength of countries, and few papers discussed the marine dependence, not to mention the coordination between the two aspects. Therefore, it is difficult to make scientific predictions on the trend of the comprehensive marine strength. The paper takes China and America as research objects, and builds evaluation index systems as well as the coupling analysis model for comprehensive marine strength and marine dependence. The conclusions are: 1) Marine dependence of America dropped consecutively in the recent 10 years, while that of China increased a lot and surpassed America in 2010. Comprehensive marine strength of America is at a steadily high level, while China witnesses a rapid development of comprehensive marine strength, which had a low starting point, and the gap between the two has diminished in the past few years. 2) The descending marine dependence of America appears digressive coupling relationship with the stable comprehensive marine strength, which restricts the development of American ocean system, indicating that America is entering a shrinking stage of marine strategy. 3) The coupling relationship between the two dimensions of China shows a favorable trend, and it is beneficial to promoting Chinese marine influence and ensuring the safety of Chinese marine dependence.

Denmark, a country along the Arctic Silk Road, wields considerable influence in Arctic affairs. Greenland constitutes the geographical basis of the Kingdom of Denmark's participation in Arctic affairs and the cornerstone in the implementation of its Arctic strategy. Nowadays, Greenland has become a transitional political entity whose internal affairs are completely independent while defense and foreign affairs are temporarily hosted by Denmark. Denmark introduced the Reform of the Danish Diplomacy and Defense and the Future of the Ministry of Defense Mission in the Arctic in 2016, which marked the transformation of Danish Arctic strategy from moderate conservatism to aggressive activism. The transformation of the Danish Arctic strategy is not only the inevitable result of profound changes in the geopolitical pattern of the Arctic, but also driven by the separatist crisis within the Kingdom of Denmark. Focusing on the strategic anchor of Greenland and persisting in the principle that “the Kingdom of Denmark is an indivisible unitary actor” constitute the cornerstone of the Danish Arctic strategy.

Since 1980s, the thoughts of the ecosystem approach and integrated marine management (IMM) have become the mainstream of marine management, which gave rise to various theoretical explorations and practical applications. The theories and practices guided by the ecosystem approach in main western oceanic countries are generalized in the paper, and the construction of marine ecological civilization in China is summarized. Meanwhile, the theory of IMM and its evolution and practices were clarified, and the historical development of IMM in China is also reviewed. Based on the discussion, a comparative analysis between the ecosystem approach and IMM is made, and the development direction of ecosystembased marine management is preliminarily proposed.