Biomimetic Design and Fabrication of Interior Architecture of Tissue Scaffolds Using Solid Freeform Fabrication

Modeling, design and fabrication of tissue scaffolds with intricate architecture, porosity and pore size for desired tissue properties presents a challenge in tissue engineering. This paper will present the details of our development in designing and fabrication of the interior architecture of scaffolds using a novel design approach. The Interior Architecture Design (IAD) approach seeks to generate scaffold layered freeform fabrication tool path without forming complicated 3D CAD scaffold models. This involves: applying the principle of layered manufacturing to determine the scaffold individual layered process planes and layered contour; defining the 2D characteristic patterns of the scaffold building blocks (unit cells) to form the Interior Scaffold Pattern; and the generation of process tool path for freeform fabrication of these scaffolds with the specified interior architecture. Feasibility studies applying the IAD algorithm to example models and the generation of fabrication planning instructions will be presented.Mechanical Engineerin

An analysis of the travel motivation of tourists from the People’s Republic of China

Since the Chinese economic reforms, the government’s policy towards travelling and tourism activity has changed. The population of the People’s Republic of China gained significant rights and possibilities to travel in their own country and conquer the international tourism market by package tours. However, the literature so far neglected the motivation of Chinese travellers in choosing their holiday destination. We compiled a new database of the preferences of Chinese tourists in domestic tourism and foreign tourists in China. The identification of the specific preferences of Chinese travellers helps to assess in how far tourists’ preferences for attractions and regions are similar. Another aspect of investigation is about the impact of tourism promotion in China on destination choice. The results of an analysis of Chinese marketing strategies are translated into recommendations for foreign travel promotion that targets at Chinese tourists.Tourism, China, travel motivation, pull factor, tourism promotion

Large-signal dynamics of an ultrafast semiconductor laser at digital modulation rates approaching 10 Gbit/s

High-fidelity pseudorandom digital modulation at 8.2 Gbit/s of an ultrahigh speed semiconductor laser is demonstrated. Studies using simple but representative pulse patterns at 10 Gbit/s give insights into the maximum digital modulation rate attainable from a given laser, as well as relations between large-signal digital performance and small-signal analog response

Integrated Coastal Zone Management in the People’s Republic of China – An Assessment of Structural Impacts on Decision-making Processes

Integrated Coastal Zone Management (ICZM) forms a generally accepted concept to ensure sustainable development in the coastal zone. The implementation of the ICZM framework as formulated, e.g. by the World Coast Conference, is often constrained by the political system within which it should be applied. This is the case in the People’s Republic of China. This study takes a political science perspective based on approaches inherent in neo-institutional and administrative theories. This way the relevant political structures are explained and the impacts that the transformation of the socio-economic system had on institutions are located. This is extended by the reflection of related political power distribution. This part of the analysis mainly contains existing knowledge on (integrated) CZM in China but evaluates it from a so far neglected point of view. The second part of the paper is taking the successful local ICZM approach of Xiamen and a proposed approach for Shanghai as an example to show that the adaptation of a working approach to other parts of the country is impossible without modifications to the organizational structures of decision-making and implementation. So far the literature emphasizes mostly modifications in content. An important reason for structural elements being comparably important is the choice of ICZM issues and the local power distribution. It furthermore shows that these are also the determining factors obstructing the upscaling of a local approach to the national level, a fact which constrains the formulation of national guidelines in China and leaves only the bottom-up alternative of introducing ICZM to China – a hard task that leaves a disproportional responsibility to the local governmental level.Integrated Coastal Zone Management, People’s Republic of China, Political Structure, Power Distribution, Jurisdictional Overlaps

Adaptation to Sea-level Rise in the People’s Republic of China – Assessing the Institutional Dimension of Alternative Organisational Frameworks

Global sea-levels are rising due to global warming. Major impacts on the world’s coasts are sand beach erosion, salination of ground water, and inundation. Adaptation is the only option to address these future threats as the mitigation of CO2 emissions is not capable of preventing sea-level rise. There are several organisational frameworks existing that can incorporate adaptation measures. Integrated Coastal Zone Management is proposed most often. Alternative frameworks are disaster management and sectoral frameworks involved in prevention activities, such as the water management that often holds responsibility for dike building. However, the integration of adaptation into an organisation framework is further dependent on institutional capacity within a political system. In order to illustrate what approach is feasible for a hierarchical political system the People’s Republic of China is taken as an example. An analysis of various frameworks and institutional responsibilities shows that the institutional dimension of organisation is decisive when seeking for an adequate framework to include adaptation to sea-level rise in. This paper is based on empirical results from a series of interviews and the analysis of official publications on frameworks and institutional responsibilities. It concludes with a recommendation on a climate change based framework.adaptation, sea-level rise, climate change, institutions, frameworks

Coastal Zone Management in the People’s Republic of China: A Unique Approach?

Integrated Coastal Zone Management, People’s Republic of China, Political Structure, Power Distribution, Jurisdictional Overlaps

Intermodulation distortion in a directly modulated semiconductor injection laser

A most important quantity in high-frequency analog transmission is the intermodulation distortion product. Experimental studies of the third order intermodulation distortion products in the modulation response of high-speed semiconductor lasers give very low values (< −60 dB) at low frequencies, an increase at a rate of 40 dB/dec as the modulation frequency is increased, and a leveling off at one-half of the relaxation oscillation resonance frequency. These experimental results can be well explained by a theory based on a perturbative analysis of laser dynamics

Analog, Digital And Short Pulse Modulation Of Ultrafast Gallium Aluminum Arsenide Semiconductor Lasers

Semiconductor lasers are potentially devices of great importance for optical transmission as well as short pulse generation for various sampling, characteration and dispersion measurements. Since semiconductor lasers are currently driven devices, it is relatively easy to modulate the optical output and to generate short pulses, on the order of 10 ps long, by directly modulating the injection current into the laser. This paper will present some recent developments in injection lasers which are capable of being analog or digitally modulated at rates up to 10 GHz, as well as generating short optical pulses at repetition rates from several hundred megahertz to tens of gigahertz

Microwave Optical Link In The Frequency Range Of 10-18 Gigahertz By Direct Modulation Of Injection Laser Diode

It is demonstrated that an ultra-high speed window buried heterostructure GaAlAs laser fabricated on semi-insulating substrate can be used as narrow band signal transmitters in the Ku-band frequency range (12-20GHz). The modulation efficiency can be increased over a limited bandwidth by a weak optical feedback. A stronger optical feedback enables one to actively mode-lock the laser diode at a very high repetition rate up to 17.5GHz, producing pulses of = 12ps long