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The purpose of this paper is to solve the interface discontinuities in radial basis function (RBF) method for multi-medium boundary value problems (BVPs). The discontinuity of the solution derivatives is not easily handled with RBF method because of infinitely smoothness.

The essence of solving BVP is to construct the continuous potential function surfaces. Hence, from constructing surface aspect, this paper proposed and compared the global and subzone schemes for RBF method. Their implementation schemes and mathematic models can then be derived. Numerical experiments and comparison are carried out for electric and magnetic field calculation.

In the numerical experiments, the subzone scheme has shown its significant advantageous, it can approximate not only the potential function but also its derivative on interface boundary with high accuracy. So the physical characteristics of discontinuities on the interface can be revealed clearly. The overall precision is significantly improved.

This paper proposed an effective subzone scheme for RBF method in multi-medium BVP. It is an improvement for RBF method based on its domain decomposition idea. And it is also a candidate for solving complex BVP.

The key purpose of conducting this review is to identify the issues that affect the structural integrity of pipeline structures. Heat affected zone (HAZ) has been identified as the weak zone in pipeline welds which is prone to have immature failures

In the present work, literature review is conducted on key issues related to the structural integrity of pipeline steel welds. Mechanical and microstructural transformations that take place during welding have been systematically reviewed in the present review paper.

Key findings of the present review underline the role of brittle microstructure phases, and hard secondary particles present in the matrix are responsible for intergranular and intragranular cracks.

The research limitations of the present review are new material characterization techniques that are not available in developing countries.

The practical limitations are new test methodologies and associated cost.

The fracture of pipelines significantly affects the surrounding ecology. The continuous spillage of oil pollutes the land and water of the surroundings.

The present review contains recent and past studies conducted on welded pipeline steel structures. The systematic analysis of studies conducted so far highlights various bottlenecks of the welding methods.

An experimental investigation for developing structure-property correlations of hot-rolled E410 steels with different carbon contents, i.e. 0.04wt.%C and 0.17wt.%C metal active gas (MAG) and cold metal transfer (CMT)-MAG weldments was undertaken.

Mechanical properties and microstructure of MAG and CMT-MAG weldments of two E410 steels with varying content of carbon were compared using standardized mechanical testing procedures, and conventional microscopy.

0.04wt.%C steel had strained ferritic and cementite sub-structures in blocky shape and large dislocation density, while 0.17wt.%C steel consisted of pearlite and polygonal ductile ferrite. This effected yield strength (YS), and microhardness being larger in 0.04wt.%C steel, %elongation being larger in 0.17wt.%C steel. Weldments of both E410 steels obtained with CMT-MAG performed better than MAG in terms of YS, ultimate tensile strength (UTS), %elongation, and toughness. It was due to low heat input of CMT-MAG that resulted in refinement of weld metal, and subzones of heat affected zone (HAZ).

A substantial improvement in YS (∼9%), %elongation (∼38%), and room temperature impact toughness (∼29%) of 0.04wt.%C E410 steel is achieved with CMT-MAG over MAG welding. Almost ∼10, ∼12.5, and ∼16% increment in YS, %elongation, and toughness of 0.17wt.%C E410 steel is observed with CMT-MAG. Relatively low heat input of CMT-MAG leads to development of fine Widmanstätten and acicular ferrite in weld metal and microstructural refinement in HAZ subzones with nearly similar characteristics of base metal.

Foreign trade zone (FTZ) usage in the United States has increased substantially in this decade. This paper discusses the major reasons for that increase, which include a favourable regulatory climate, growing awareness of the competitive benefits of operating within a zone, and community interest in promoting zones as an incentive to attract investment. Examined here are developments in the Mid‐American region, which reflect national trends. In Indiana, illinois, Ohio and Michigan there is considerable interest in general purpose zones, but so far business use has been limited. The major activity is occuring in subzones in individual manufacturing plants, and this is likely to continue in the region as well as nationally.

This article examines the issues related to US foreign‐trade zones as perceived by the zone managers. A longitudinal study of foreign‐trade zone managers was conducted. The results of the two surveys and an extensive dialogue with foreign‐trade zone managers suggest a continuing lack of awareness and understanding of the benefits of zone operations on the part of potential zone users. Implications are discussed from a marketing management perspective.

This article discusses the competitive advantage firms can derive from the wise utilization of foreign trade zones. Recent environmental changes which have necessitated an increasing use of FTZs are discussed, as well as the benefits offered by FTZs as compared to other government tariff incentive programs. Several examples demonstrate the various ways information is given regarding the money required and the time involved in the establishment and use of an FTZ or a subzone.

In 2008, a bill was introduced in the 110th Congress (HR6415) to address the “unintended consequences” of US free trade agreements (US FTA) on manufacturers operating in US foreign trade zones (FTZs). Presently, US manufacturers operating in FTZs that use imported components pay a tariff (on finished goods entering the US market), which is not paid by their competitors in countries that have free trade agreements (FTAs) with the USA. The purpose of this paper is to explore the implications of a legislative proposal to address this issue (the bill is still under consideration and not yet been passed by Congress) for domestic firms and the overall economy.

The paper is largely based on the analysis of the legislative proposal (HR6415), and US trade data obtained from the United Nations.

The paper shows that the trade agreement parity (TAP) proposal may have the undesirable effect of encouraging local firms (in US FTZs) to use foreign components and increasing the trade deficit. It also shows that the proposal, by facilitating the entry of more foreign imports undermines the original purpose for which FTZs were designed.

There are no papers examining the implications of this Congressional bill on domestic competition and the overall US economy. This paper and its recommendations will help US policymakers to re‐evaluate the existing proposal and also revisit the role of FTZs in the US economy.

The purpose of this paper is to research whether microstructure varieties of zones at welded joints pose a tremendous effect on its corrosion in SC-CO₂.

The interrelation between the corrosion and microstructure of base metal (BM), fine grain heat affected zone (FHAZ), coarse grain heat affected zone and weld metal (WM) in welded of X80 steel in water saturated supercritical CO₂ was studied by using optical microscope, weight loss test, electrochemical measurements and surface analytical techniques.

The all subzones of X80 weld joints were attacked by SC-CO₂ corrosion and showed flower-like corrosion scale spots consisted of granular FeCO₃. The most severe corrosion appeared at WM due to lower proportion of ferrite to pearlite, but the slightest corrosion displayed at BM. GHAZ with larger grains and more polygonal ferrite exhibited more severe corrosion than that at BM. Due to its smaller grain, FHAZ displayed comparatively more severe corrosion to that at BM.

There exists close interrelation between the corrosion and microstructure of the welded carbon steel in water saturated supercritical CO₂.

Climate and disaster resilience mapping has been discussed in detail in Chapter 3. The Climate Disaster Resilience Index (CDRI) as a comprehensive and well-structured methodology for measuring the resilience of cities is presented, as well as the differences between CDRI and various assessment tools. The resilience of cities, or their agglomerations or subzones, is being measured because cities are seen to be at a suitable level to efficiently initiate action, especially in developing countries where unplanned or haphazard urbanization is a major risk factor. But for climate and disaster resilience mapping to be of value, it should be followed by action planning. Having a vision for the future and charting a course to achieve it is what action planning is about. Studies have consistently shown that vision, planning, and goal setting can positively influence cities’ organizational performance. Action planning can compel future thinking, highlight new opportunities and threats, and refocus a city's mission. Productive action planning focuses on the most critical problems, choices, and opportunities. Action planning requires time and a process. If used effectively, it is a powerful tool for self-management and goal-based achievement. Action planning typically includes deciding who is going to do what and by when and in what order for the city to reach its long-term goals. The design and implementation of the action planning depend on the nature and needs of the city.

The investigations provide a basis for the optimization of the alloy 6061-T6 friction stir welding (FSW) process to improve the mechanical properties of welded joints.

The local deformation of the FSW joint in tension and fatigue test were experimentally investigated by digital image correlation (DIC) technique.

The local stress-strain behaviors of the sub-regions show that the plastic strain always concentrated at the heat affected zone (HAZ) on the advancing side both in tension and high cycle fatigue and eventually leads to the final fracture. The evolution of the plastic strain at very low stress is extremely slow and accounts for most of the total fatigue life. However, the local deformation exhibits a sudden increase just before the fatigue failure.

Based on the experimental data, the result indicates that the HAZ is the weakest zone across the weld and the strain localization in high cycle fatigue is very harmful and unpredictable for the FSW joints.