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This paper aims to elucidate the effects of lubricant groove shape, vertical load, swing angle and grease injection cycle on the friction and wear performances of journal bearings under the grease lubrication condition.

Three different types of lubricant grooves, namely, numeral eight-shaped, axial straight line-shaped and circular blind hole-shaped, were designed and machined in the bearing bush of journal bearings. The tribological behaviors of these journal bearings were investigated on the self-developed reciprocating swing friction and wear tester. Experimental data including the friction coefficient, the friction temperature, the wear loss and wear time were analyzed in detail. The wear morphologies of friction pairs were observed by scanning electron microscope and confocal laser scanning microscope.

The load carrying capacity and service life of the journal bearing with circular blind hole-shaped lubricant grooves are not affected. However, the load carrying capacities of journal bearings with numeral eight-shaped and axial straight line-shaped lubricant grooves are declined. The coverage areas of lubricating grease in the bearing bush are associated with the swing angle. The smaller the swing angle is, the more limited the coverage areas of lubricating grease get. Among these journal bearings, the maintenance-free time of journal bearing with circular blind hole-shaped lubricant grooves is the longest because of its large grease storage capacity.

The journal bearing with circular blind hole-shaped lubricant grooves exhibits the excellent antifriction and wear-resistant properties, making it suitable for the application in the low-speed and heavy-load engineering conditions.

China is among one of the oldest civilizations in the world. The massive land mass of China also means that the Chinese people are subject to weather extremes as well as topographical variety in a country which cuts across alpine heights, treacherous deserts, lush valleys, dusty plains and lengthy rivers. With these weather extremes as the backdrop, it is crucial for the Chinese people to develop appropriate environmental control techniques for their dwellings as well as to ensure the structural integrity of their buildings. This paper discusses the protection, heating, anti‐seismic and dampness techniques developed and implemented in ancient China. It also documents the measures taken by the ancient Chinese to ensure the structural integrity of their buildings. The examples highlighted in this paper suggest that the building science principles adopted in ancient China remain relevant in the construction industry today.

The New Zealand (NZ) dairy industry faces the challenge of increasing productivity and dealing with public concerns over nutrient pollution. The effective policy needs to address regional differences in productivity and fertilizer use. The purpose of this paper is to investigate how spatial effects influence the relationship between dairy yields and intensive farming practices across regions in NZ.

This paper employs spatial panel data models to establish whether unobserved spatial effects exist in the relationship between dairy yields and nutrient inputs regionally and nationally using 2002, 2007 and 2012 data from Statistics NZ and DairyNZ.

The results show positive spatial spillovers for most intensive inputs. The high level of effluent use and estimated negative yield response to nitrogen suggests that an opportunity exists for greater use of effluent as a substitute for nitrogenous fertilizer. Substitution has the potential to reduce dependence on fertilizer and contribute to a reduction in the nutrient pollution.

This paper is the first empirical application of spatial econometric methods to examine the spatial relevance of dairy yields and intensive farming in NZ. In particular, the spatial panel data model accounts for cross-sectional dependence and controls for heterogeneity. The results contribute to an understanding of how farmers can improve their management of intensive inputs and contribute to the formation of regional environmental policy that recognizes regional heterogeneity.

Construction works, which contributed to the built environment of the primitive, slave and feudal societies in ancient China, constitute an important component of Chinese history. This paper discusses the nest and cave dwellings as well as the tools used in the primitive society (before 2100 BC) of China. Construction works in the Slave Society (2100‐500 BC) encompassed the construction of city walls as well as wood and earth structures, covering roofs, wall and floor facing, and drainage facilities. The invention of new building materials and construction tools as well as standardization in working procedures and material consumption are discussed in “Feudal society” (221 BC‐AD 1840). The paper suggests that the more than 5,000 years of rich history of construction works in China should not be ignored.

Reflow soldering process is an important step of the surface mount technology. The purpose of this paper is to minimize the maximum warpage of shielding frame by controlling reflow soldering control parameters.

Compared with other reflow-related design methods, both time and temperate of each extracted time region are considered. Therefore, the number of design variable is increased. To solve the high-dimensional problem, a surrogate-assisted optimization (SAO) called adaptive Kriging high-dimensional representation model (HDMR) is used.

Therefore, the number of design variable is increased. To solve the high-dimensional problem, a surrogate-assisted optimization (SAO) called HDMR is used. The warpage of shield frame is significantly reduced. Moreover, the correlations of design variables are also disclosed.

Compared with the original Kriging HDMR, the expected improvement (EI) criterion is used and a new projection strategy is suggested to improve the efficiency of optimization method. The application suggests that the adaptive Kriging HDMR has potential capability to solve such complicated engineering problems.

To ensure the stable operation of ironmaking process and the quality and output of sinter, the multi-objective optimization of sintering machine batching process was carried out.

The purpose of this study is to establish a multi-objective optimization model with iron taste content and batch cost as targets, constrained by field process requirements and sinter quality standards, and to propose an improved balance optimizer algorithm (LILCEO) based on a lens imaging anti-learning mechanism and a population redundancy error correction mechanism. In this method, the lens imaging inverse learning strategy is introduced to initialize the population, improve the population diversity in the early iteration period, avoid falling into local optimal in the late iteration period and improve the population redundancy error correction mechanism to accelerate the convergence rate in the early iteration period.

By selecting nine standard test functions of BT series for simulation experiments, and comparing with NSGA-?, MOEAD, EO, LMOCSO, NMPSO and other mainstream optimization algorithms, the experimental results verify the superior performance of the improved algorithm. The results show that the algorithm can effectively reduce the cost of sintering ingredients while ensuring the iron taste of sinter, which is of great significance for the comprehensive utilization and quality assurance of sinter iron ore resources.

An optimization model with dual objectives of TFe content and raw material cost was developed taking into account the chemical composition and quality indicators required by the blast furnace as well as factors such as raw material inventory and cost constraints. This model was used to adjust and optimize the sintering raw material ratio. Addressing the limitations of existing optimization algorithms for sintering raw materials including low convergence accuracy slow speed limited initial solution production and difficulty in practical application we proposed the LILCEO algorithm. Comparative tests with NSGA-III MOEAD EO LMOCSO and NMPSO algorithms demonstrated the superiority of the proposed algorithm. Practical applications showed that the proposed method effectively overcomes many limitations of the current manual raw material ratio model providing scientific and stable decision-making guidance for sintering production operations.

The study aims to carry out the production of a bulk heterojunction organic solar cell in a laboratory scale using a blend of poly (3-hexylthiopene) (P3HT) and [6, 6]-phenyl (C61) butyric acid methyl ether (PCBM).

Four inverted geometry organic solar cells were prepared based on 1:1 ratio of P3HT to PCBM and subjected to post annealing at different temperatures of 32, 120, 130 and 140°C. Solar cells were fabricated with structure glass/ITO/P3HT:PCBM/PEDOT:PSS/Au and characterized using Keithley 2400 series sourcemeter and a multimeter interfaced to a computer system with a LabVIEW software, which showed both dark and illumination current–voltage characteristic curves. Four reference cells were also fabricated with structure soda lime glass/P3HT:PCBM and annealed at different temperatures of 32, 120, 130 and 140°C.

The third organic solar cell prepared, Sample CITO, had the best performance with power conversion efficiency (PCE) of 2.0281 per cent, fill factor (FF) of 0.392, short circuit current of −0.0133 A and open circuit voltage of 0.389 V. Annealing of active layer was found to improve cell morphology, FF and PCE. Annealing of the active layer at 140°C resulted in a decrease of the PCE to 2.01 per cent.

These findings are in good agreement with previous investigation in literature which reported that best annealing temperature for a 1:1 ratio blend of active material is 130°C. Ultraviolet–visible spectra on reference cells showed that sample CITO had wider absorption spectra with peak absorbance at a wavelength of 508 nm.

This research is purely original.

The purpose of this investigation was to identify the association between Experience Use History (EUH) and types of substitution choices of hikers with the perspectives of activity involvement and place attachment. On-site surveys were distributed by systematic sampling technique to obtain a representative sample of hikers with 51% response rate. The theoretical expectation was confirmed by these data. Findings indicated that among four EUH classifications, Veterans and Visitors who perceived higher levels of activity involvement and relatively lower levels of place attachment tended to make resource substitutability, while Locals who scored highest on place attachment chose to make temporal substitutability and Beginners who scored lower on both activity involvement and place attachment were apt to make both resource and activity substitutability. Suggestions and managerial implication are further discussed.

A destination's ability to attract tourists is associated with the visitor experience and, in recent years, visitors have increasingly used virtual environments and digital innovation, such as social media platforms, to communicate their experience of tourist destinations. A positive well-communicated tourist experience improves the reputation of the destination and has relevant consequences for both the destination's attractiveness and its competitive advantage. On the contrary, when the destination's reputation is negatively affected by visitors' experiences, comments and reviews, such destination might compromise its ability to attract new visitors. Studies in this field agree alike that the tourist experience is negatively affected by overcrowding and overflows phenomena occurring around the visited city attractions. The present research, merging the aforementioned observations, investigates whether visitor density affects the online reputation of the Uffizi Gallery, estimated by extracting visitors' opinions and feedbacks on the city's main attractions from TripAdvisor ratings and from Twitter posts, by applying sentiment analysis to evaluate whether the text is positive, negative, or neutral. The city of Florence is an ideal case study, as the city records almost 16 million tourist overnight stays per year hence highly exposed to the risk of tourist overcrowding and overflows. The research findings reveal that Uffizi Gallery experiences and mood are influenced by the number of visitors insisting and if tourists live a negative experience, this is further exacerbated by the growing density of visitors themselves. We find that, if tourists have a negative experience, this is exacerbated by the density of visitors to the Uffizi Gallery. The results reveal also that tourists' experiences are even more influenced by any general dissatisfaction they experience in the city of Florence in a broader way. Practical implications and theoretical contributions are discussed.

The purpose of this paper is to improve the generation efficiency of singlet oxygen of methylene blue molecules through finely controlling their aggregation states in drug carriers.

As a photosensitiser in photodynamic therapy, methylene blue (MB) was loaded on citrate-modified hydroxyapatite (HAp) through an electrostatic interaction and followed by encapsulation of coordination complexes of tannic acid (TA) and Fe(III) ions. Ultraviolet-visible absorption spectrum of the supernatant after incubation of samples was recorded at certain time interval to investigate the release behaviour of MB. Photodynamic activity of MB was determined by the oxidation reaction of uric acid by singlet oxygen generated by MB under illumination.

Almost all MB molecules were immediately released from HAp-MB, whilst an initial burst release of MB from HAp-MB@TA was followed by a sustainable and pH-sensitised release. In comparison with HAp-MB, photocatalystic reduction of HAp-MB@TA by titanium dioxide hardly occurred under illumination, indicating the stability against reduction to leukomethylene blue in vitro. Generation efficiency of singlet oxygen by MB released from HAp-MB@TA was significantly higher than that from HAp-MB because of the control of TA and Fe(III) ions complexes on molecular structures of released MB.

A facile method was herein demonstrated to optimise the generation efficiency of singlet oxygen by controlling aggregation states of PS molecules and improve PDT efficiency to damage tumour tissues.