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The purpose of this paper is to perform the thermo-hydro-mechanical (THM) numerical analysis in order to study the thawing process for frozen soil and to predict the thawing settlement.

A new one-dimensional multi-field physical coupled model was proposed here to describe the thawing process of saturated frozen soil, whereby the void ratio varied linearly with effective stress (Eq. 10) and hydraulic conductivity (Eq. 27b). The thawing process was simulated with different initial and boundary conditions in an open system with temperature variations. The mechanical behavior and water migration of the representative cases were also investigated.

The comparisons of representative cases with experimental data demonstrated that the model predicts thawing settlement well. It was found that the larger temperature gradient, higher overburden pressure and higher water content could lead to larger thawing settlement. The temperature was observed that to distribute height linearly in both frozen zone and unfrozen zone of the sample. Water migration forced to a decrease in the water content of the unfrozen zone and an increase in water content at the thawing front.

In this study, only the one-directional thawing processes along the frozen soil samples were investigated numerically and compared with test results, which can be extended to two-dimensional analysis of thawing process in frozen soil.

This study helps to understand the thawing process of frozen soil by coupled thermo-hydro-mechanical numerical simulation.

The integration of e‐business and supply chain enables seamless information flow from suppliers to customer service network via the internet. It also enables better‐coordinated materials flow from customer order to production, storage, distribution and delivery. The purpose of this paper is to describe the work that leads to the realisation of a hierarchical model for e‐supply chain coordination and optimisation.

The model is based on an e‐business information flow network in order to respond rapidly to the dynamics of e‐supply chain and market. It can be used to realize management level strategies, and facilitate the planning and control of detailed operation schedules of supply chain units in an e‐supply chain environment. Three main modules are discussed. They are routing and sequence optimiser (RSO) with the aid of a GA and TS‐based multiple population search strategy (MPSS); supply chain virtual clustering (SCVC) based on fuzzy virtual clustering; and supply chain order scheduling (SCOS) using an agent‐based distributed scheduling system.

These modules enable: the generation of preferred routings, transportation modes and work order plan under such constraints as customer service level, cycle time and cost; the formation of supply chain's unit‐transportation‐work order families using a clustering approach to down‐size supply chain problems and increase computation efficiency; and the integration of scheduling with supply chain optimisation in order to facilitate the control of a supply chain with the aid of an agent‐based distributed scheduling approach.

This paper proposed a hierarchical model for e‐supply chain coordination and optimisation that is capable to solve large‐scale problems. A MPSS using GA and TS was depicted in detail to expedite the RSO.

The aim of this paper is to investigate inhibition of copper corrosion by 3,5‐bis(2‐thienyl)‐4‐amino‐1,2,4‐triazole (2‐TAT) in 1 M HCl and 0.5 M H₂SO₄.

Potentiodynamic polarization curves and electrochemical impedance measurements were carried out on copper in 1 M HCl and 0.5 M H₂SO₄ containing various concentrations of 2‐TAT, and the effects of temperature were also investigated.

As an efficient inhibitor, 2‐TAT behaves better in 1 M HCl than in 0.5 M H₂SO₄. 2‐TAT can be classified as cathodic‐type corrosion inhibitor in 1 M HCl and acts as relatively mixed type in 0.5 M H₂SO₄. Activation energies in the presence and absence of 2‐TAT were obtained by measuring the temperature independence of corrosion current. Adsorption of the inhibitor on the copper surface was found to obey the Langmuir adsorption isotherm.

This inhibitor could have application in industries where hydrochloric acid solutions are used to remove scale and salts from copper surfaces and may render dismantling unnecessary.

The results from this paper showed that 2‐TAT could be considered as a suitable inhibitor for copper in acidic media.

This paper aims to give meaning to the smart tourism destination (STD) certification, highlighting its main advantages and limitations. The case of Medellín (Colombia) presents characteristics worth studying. The city has suffered from stigmatization and has recently started the steps to become an STD with the Spanish company Segittur (December 2020). Thus, this study aims to focus on the implications of the STD process, especially in an area that has been impacted by tourist activity.

This paper is a qualitative and exploratory case study about Medellín in Colombia and its tourism development in an STD framework. After a theoretical exploration of the STD from an urban perspective, the paper will present a multiple data corpus to analyze the city’s certification process to turn into an STD. This methodology explores stakeholders on the destination, including an observation, and allows us to obtain an overview of the implications of the STD certification for Medellín.

During the past decade, Medellín passed from a dangerous destination to a trendy destination. Findings reveal interesting results, considering the need to consider all aspects of territory as a central issue for the STD settlement and look beyond a technological approach.

This paper lets to understand better the STD process established by the institution. Moreover, it highlights the gap between the coveted certification to become the first STD in Colombia and the realities of a Latin American territory.

Este articulo pretende dar un significado a la certificación de destino turístico inteligente (DTI), destacando sus principales ventajas y limitaciones. El caso de Medellín (Colombia) presenta características relevantes de estudio. La ciudad ha sido ampliamente estigmatizada y recientemente ha iniciado el proceso de certificación para convertirse en destino turístico inteligente con la entidad española Segittur (dic. 2020). Dicho esto, queremos enfocarnos en las implicaciones de este proceso, especialmente en un área que ha sido impactada por la actividad turística.

Este artículo comprende un estudio cualitativo y exploratorio sobre Medellín en Colombia y su desarrollo turístico en un marco de DTI. Luego de una exploración teórica del destino turístico inteligente desde una perspectiva urbana, el artículo presentará un corpus de múltiples datos para analizar el proceso de certificación de la ciudad en su conversión en una DTI. Nuestra metodología explora a los stakeholders sobre el destino, incluyendo una observación, y nos permite obtener una visión general de las implicaciones de la certificación DTI para Medellín.

Durante la última década, Medellín pasó de ser un destino denominado de alto riesgo a un destino altamente recomendado. Los hallazgos revelan resultados interesantes, mostrando la necesidad de considerar todos los aspectos del territorio como un tema central para el asentamiento del DTI y mirar más allá de un enfoque tecnológico.

Este trabajo permite tener una mejor comprensión del proceso de DTI establecido por la entidad Segittur. Además, resalta la brecha existente entre la deseada certificación y las realidades de un territorio latinoamericano.

This paper aims to investigate the attitude regulation for spacecraft in the presence of time-varying inertia uncertainty and exogenous disturbances.

The high gain approaches are typically used in existing researches for theoretical advantages, bringing better performance but sensitive to parameter selection, making the controller conservative. A reset-control policy is presented to achieve the spacecraft attitude control with easy control parameter tuning.

The reset-control policy guarantees satisfying control performance despite using performance tuning function and saturation function besides reducing the conservativeness of the controller, thus reducing the effort in tuning control parameters.

Notably, the adaptive function owns a reset mechanism, which is reset to a preset condition when the controlled variable crosses zero. The mathematical analysis also shows the system trajectory can converge to a set centered at the origin.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Examines the ninth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Considering the external disturbances and dynamic uncertainties during the process of the trajectory tracking, this paper aims to address the problem of the welding robot trajectory tracking with guaranteed accuracy.

The controller consists sliding mode control, fuzzy control and low pass filter. The controller adopts low-pass filter to reduce the high frequency chattering control signal in sliding mode control. The fuzzy control model is used to simulate the external disturbance signal and the dynamic uncertainty signal, so that the controller can effectively restrain the chattering caused by the sliding mode control algorithm, realizing the track of the welding robot effectively and improving the robustness of the robot.

An innovative experiment device was adopted to realize the performance of the proposed controller. Considering the kinematic and dynamic uncertainty during the process of robot tracking, the tracking accuracy was realized within 0.3 mm.

This paper uses Lyapunov stability theory and Barbalat theorem to analyze the stability of the proposed controller.