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Over the past three decades, a small community of eighty-four Chilean low-income families has built and improved their home incrementally, without any technical assistance, showing an impressive performance. A six square meters bathroom on a serviced plot of land with individual connection to potable water, sewerage, electricity and access roads, worked as a starting point back in 1974. However particular their rationale may seem, the individual history of their housing process reveals some general regularities in occurrence and duration of self-build activities, as well as size and allocation of the domestic spaces. A small random sample of fifteen households was selected to tell the story and explain the whys, hows, and whens of an ever-evolving housing process. Semi-structured interviews and building surveys were both combined to reconstruct the sequence of states of each housing process, with the awareness of the characteristic imprecision of oral information transfer. Alternative states were explored by constraint programming methods and spatial qualitative reasoning. Considering the hard constraints over the site morphology and services allocation, the results of the exploration stress how extraordinary lucid and intuitive the surveyed families are when making their design decisions. The article exposes a reconstructive case study on spontaneous growth patterns underlying an unassisted, incremental self-build housing dynamics.

The purpose of this paper is to analyze the relationship between researchers’ social media (SM) behavior and their academic performance.

A sample of 362 researchers was recruited from the colleges of management of 52 Chinese universities. A factor analysis of eight indices retrieved from the 362 data items was conducted. A total of 24 Chinese researchers were interviewed and given a robust test.

The results indicate that Chinese general social media (GSM) is insufficient to support academic research and it is difficult for scholars to enhance the visibility of their academic performance using GSM platforms, which can actually induce addiction. University resources, management systems, and working environment affect how scholars apply SM.

The authors examined the researchers’ SM behavior by giving them a questionnaire and interview; however, this approach proved inadequate. The academic performance of researchers is affected by numerous factors, but the authors only considered SM behavior.

It is suggested that universities apply academic social media (ASM) indicators to measure researchers’ contributions so that they self-regulate their SM usage attitudes. Also, universities should also promote ASM platforms.

This study analyzed scholars’ GSM usage and academic performance, and the moderating effect of university level on the relationship between need for competence and relatedness and need for autonomy. This comprehensive analysis contributes to the scholarly SM usage literature.

Qualitative data analysis requires methodological knowledge and intellectual competence. Analysis is not about adhering to any one correct approach or set of right techniques; it is imaginative, artful, flexible, and reflexive. It should also be methodical, scholarly, and intellectually rigorous. (Coffey and Atkinson, 1996, p.1.

The purpose of this paper is to improve the lubrication performance of a water-lubricated polymer bearing with axial grooves, especially enlarge the minimum film thickness.

The bearing diameter is enlarged near the axial ends of the journal, with axial openings of a trumpet shape. A numerical model is developed which considers the proposed trumpet-shaped openings, bush deformation and grooves. The generatrix of the trumpet-shaped opening is assumed to be a paraboloid. Three different variations are covered, and the influences of the trumpet-shaped openings’ parameters on the bearing performance are analyzed.

The appropriate trumpet-shaped openings at the axial ends effectively increase the minimum film thickness, and the impact of trumpet-shaped openings on load carrying capacity is very small or even negligible. For the water-lubricated polymer bearing with axial grooves analyzed in this paper, the appropriate trumpet-shaped openings increase the minimum film thickness from 0.53 to 11.14 µm and decrease the load carrying capacity by 2.48 per cent.

The results of this study can be applied to marine propeller shaft systems and other systems with polymer bearings.

This paper has presented an approach for significantly increasing the minimum film thickness of a water-lubricated polymer bearing. A study on the performance improvement of water-lubricated polymer bearings with axial grooves is of significant interest to the research community.

In the 1990s, following the challenges imposed by globalisation, the liner shipping industry experienced profound changes, leading major carriers to create ad-hoc logistics business-units. Nevertheless the vertical integration of shipping lines along the transport chain faced important entry barriers in various regions.This paper aims at analysing the impact of such barriers on carriers’ pathways of expansion in the logistics business. It mainly focuses on the East-Asian market, as a relevant empirical case in which important institutional and socio-political obstacles are still in force .Main results disclose sui-generis paths of expansion achieved by major carriers, in contrast with linear constructs of time and space proposed by classical TNC theories. In such respect, port operations reveal to be the most critical stage of the chain. The ‘sidestep’ of the port phase, leading to investments in other on-shore activities (warehousing, inland terminals, etc.) as well as the implementation of aggressive financial campaigns (acquisitions and takeovers), reveal the unfaltering will of top shipping lines: the quick achievement of a successful vertical and horizontal expansion despite environmental obstacles.

Indirect electrochemical oxidation and electro-flocculation were combined to degrade indigo wastewater.

The degradation efficiency of indigo wastewater in single-cell and double-cell were investigated. Based on the previous single factor experiments, the oxidative degradation conditions of indigo wastewater in single cell were optimized by response surface methodology (RSM). The decolorization rate, chemical oxygen demand (COD) removal rate, the contents of flocculation precipitation and indigo were measured and analyzed.

The degradation efficiency in single cell was higher than in double cell. The electrolysis conditions were optimized by RSM and the decolorization rate was 99.01% with COD removal rate of 60.34% and conductivity of 89.75 mS/cm. The amount of flocculated precipitation decreased by 53.33% and the indigo increased by 86.34%. The content of Na and S decreased by 12.13 and 6.49%, respectively. The ratio of Fe3+ to Fe2+ in the solution was 4.62:1, indicating that most of the iron dropped on the electrode sheet was converted to Fe3+.

The one-step electrochemical oxidation and flocculation method with the advantages of simple operation and environmental protection, provided a reference for the actual treatment of dyeing wastewater.

Combining the electrochemical flocculation and oxidation provided an efficient and practical solution for degradation of indigo wastewater.

Combining the advantages of electrochemical oxidation and electroflocculation, the application of electrochemistry in printing and dyeing wastewater treatment technology has been expanded.

Magnesium-aluminum layered double hydroxides (LDH) with a platelet-like morphology were synthesized through a modified co-precipitation method. The purpose of this paper is to investigate calcined Mg-Al-CO₃ LDH (CLDH) as chloride ion traps.

The morphology and chemical composition of the synthesized materials were studied through UHR-SEM, EDS, FT-IR and XRD. The chloride ion adsorption was confirmed by XRD; the characteristic diffraction peaks of the reconstructed LDH structure were revealed, similar to the one before the thermal treatment process. The effect of varying the experimental conditions on the chloride ion adsorption, such as the initial target-ion concentration, the adsorbent material dosage, the solution temperature and the solution pH was also investigated.

The experimental data fitting revealed that the Langmuir equation is a better model on the basis of correlation coefficients (R²) and that the pseudo-second kinetic model can satisfactorily describe the chloride ion uptake.

The ability of Mg-Al CLDH to recover their layered structure upon exposure to aqueous sodium chloride solutions with concentrations up to 0.3 M (10,636 mg/L) through the chloride adsorption and the simultaneous rehydration process is clearly demonstrated.

This review paper reveals the literature on ultrasonic, chemical-assisted ultrasonic and rotary ultrasonic machining (USM) of glass material. The purpose of this review paper is to understand and describe the working principle, mechanism of material removal, experimental investigation, applications and influence of input parameters on machining characteristics. The literature reveals that the ultrasonic machines have been generally preferred for the glass and brittle work materials. Some other non-traditional machining processes may thermally damage the work surface. Through these USM, neither thermal effects nor residual stresses have been generated on the machined surface.

Various input parameters have the significant role in machine performance characteristics. For the optimization of output response, several input parameters have been critically investigated by the various researcher.

Some advance types of glasses such as polycarbonate bulletproof glass, acrylic heat-resistant glass and glass-clad polycarbonate bulletproof glass still need some further investigation because these materials have vast applications in automobile, aerospace and space industries.

Review paper will be beneficial for industrial application and the various young researcher. Paper reveals the detail literature review on traditional ultrasonic, chemical assisted ultrasonic and rotary USM of glass and glass composite materials.

High-silicon chromium iron (HSCI) has been used in ground grids in southern China, while there was a lack of study on its corrosion behavior in this soil environment. The purpose of this paper is to discover the corrosion of HSCI in acidic and alkaline soil solutions.

The original defects on the HSCI surface were observed using optical microscopy, and the corrosion behavior of the HSCI in the acidic and alkaline soil solutions were jointly detected using electrochemical measurements and scanning electron microscopy/energy dispersive spectrometer.

The results showed the corrosion rates of the HSCI in the acidic and alkaline soil solutions were limited, and the high contents of Cr and Si in matrix was responsible for its high corrosion resistance. The HSCI showed a similar corrosion tendency in the two solutions, while its corrosion rate in the acid soil solution was higher than that in the alkaline soil solution. The corrosion pits on the specimen surface were originated from the original defects in matrix, and the edges of the corrosion pits were more rounded than the original defects after 720 h immersion in the two solutions. The original defects in the HSCI matrix played a significant role in the corrosion process.

The paper discovered the corrosion evolution of HSCI in the acidic and alkaline soil solutions. What is more, the acceleration role of the original defects on the corrosion of the HSCI in the acidic and alkaline soil solutions was discovered in the paper. The results are beneficial for the material selection of ground grid equipment in engineering.

Traditional models of full and open competition are generally applied for ordinary public procurement contracts, whereas special competitive procedures (such as unsolicited proposals) are permissible under various international and domestic frameworks for “Public-Private Partnership” (PPP) contracts. In case of the latter category of contracts, some concerns about relative lack of transparency and competition in the award process have begun to surface, while they are being increasingly relied upon for development of public infrastructure and services. This paper focuses on certain aspects of competition and transparency in the award of PPP contracts, vis-à-vis normal public procurement contracts. To facilitate a sharper identification of legal issues, it compares the relevant regulations and case law in India applicable to unsolicited proposals (UNPs) with that in the United States and those under available international frameworks. It concludes with recommendations on identified legal dimensions of UNPs with reference to government obligations on transparency and competition, so as to adequately preserve these elements in procurement of PPP infrastructure projects.