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The purpose of this study is to use the individual blade pitch control (IBC), reduce actively both the rotor hub vibratory loads and airframe vibration responses for the lift-offset compound helicopter at a high-speed flight condition.

The Sikorsky X2 technology demonstrator (X2TD) is used as the lift-offset compound helicopter. The X2TD lift-offset rotor is modelled and its rotor hub vibratory loads at a flight speed of 250 knots are predicted using a rotorcraft comprehensive analysis code, CAMRAD II, and the airframe structural dynamics is represented with a finite element analysis code, MSC.NASTRAN. When the propulsive trim methodology is applied for rotor trim, the best input condition for IBC using multiple harmonic inputs is searched to reduce the rotor vibration, while the rotor aerodynamic performance (the rotor effective lift-to-drag ratio) is improved or maintained at least. Finally, the reduction in airframe vibration responses is investigated when the best input condition for IBC with multiple harmonics is applied to the lift-offset rotor.

When the IBC with the single harmonic input using the 2/rev actuation frequency, amplitude of 2° and control phase angle of 120° (2P/2°/120°) is considered for X2TD rotor, the rotor vibration is reduced by about 26.37% only and the rotor effective lift-to-drag ratio increases slightly by 0.98%. When X2TD rotor uses the IBC with multiple harmonic inputs (2P/2°/45° + 5P/1°/90°), the rotor hub vibratory loads and airframe vibration responses are reduced by 44.69% and from 0.48 to 79.10%, respectively, while rotor effective lift-to-drag ratio is improved by 0.77%, as compared to the baseline without IBC.

This study is the first study to use the 2/rev actuation for IBC to the four-bladed lift-offset coaxial rotor and to investigate to obtain simultaneously the rotor vibration reduction, rotor performance improvement and airframe vibration reduction, using IBC with multiple harmonic inputs.

The purpose of this study is to provide a full understanding of library use patterns in their full temporal and spatial environment. By analyzing individuals' daily travel activity, this study seeks to measure the travel distance and travel time of library users in multi‐destination trip settings.

The data set for analysis was collected from the Metropolitan Travel Survey Archive, which stores 79 household daily travel data sets. Daily activities of 409 people who visited public libraries were extracted from the Puget Sound Region data set.

Through the analysis, four library access patterns were identified: single‐destination, en route, base camp, and trip‐chaining trips. Only 20 percent of library users made single‐destination trips, while 80 percent of users made trips of a multi‐destination nature; these are depicted by the latter three listed patterns. In particular, 62.2 percent of the activities fell into the trip‐chaining travel pattern. Such a pattern is defined as “discretionary activities which include a library visit.” Findings indicate that although travel distance is still a constraint to library access, travel time is a more informative factor than travel distance for gaining a richer understanding of the nature of library visits.

This study develops new measurements of travel distance and time, D_library and T_library respectively, enabling more accurate measures of travel distance and time, and further supporting precise measurements of the portions of multi‐destination trips most relevant to library visits.

This study aims to highlight a series of accidents epitomized by the success of a music artist, bringing three streams of literature together – pop culture, entrepreneurship and place branding.

Using an illustrative case of a 2012 YouTube hit song, Oppan Gangnam Style, by Korean artist Park Jae-Sang, the artist’s attempt to lampoon the extravagant lifestyle of Gangnam District’s residents accidentally puts them on the global map. The narrative is built around the storytelling approach.

The study highlights the intersections of pop culture creativity and entrepreneurship (albeit accidental) with implications for place branding.

The study is overtly documentary analysis-based and could, therefore be subjected to quantitative analysis in future research. Furthermore, the conceptual model could be tested with additional cases in the future.

In a broad sense, this study is a pioneering effort in the field of entrepreneurship and its interconnections with other disciplines – marketing (place and entrepreneurship) and pop culture. The conceptual model could form a basis for future research in such intersections.

This paper aims to compare the comprehensive rotorcraft analyses using the two different blade section property data sets for the blade natural frequencies, airloads, elastic deformations, the trimmed rotor pitch control angles and the blade structural loads of a small-scale model rotor in a blade vortex interaction (BVI) phenomenon.

The two different blade section property data sets for the first Higher-harmonic control Aeroacoustic Rotor Test (HART-I) are considered for the present rotor aeromechanics analyses. One is the blade property data set using the predicted values which is one of the estimated data sets used for the previous validation works. The other data set uses the measured values for an uninstrumented blade. A comprehensive rotorcraft analysis code, CAMRAD II (comprehensive analytical model of rotorcraft aerodynamics and dynamics II), is used to predict the rotor aeromechanics such as the blade natural frequencies, airloads, elastic deformations, the trimmed rotor pitch control angles and the blade structural loads for the three test cases with and without higher-harmonic control pitch inputs. In CAMRAD II modelling with the two different blade property data sets, the blade is represented as a geometrically nonlinear elastic beam, and the multiple-trailer wake with consolidation model is used to consider more elaborately the BVI effect in low-speed descending flight. The aeromechanics analysis result sets using the two different blade section property data sets are compared with each other as well as are correlated with the wind-tunnel test data.

The predicted blade natural frequencies using the two different blade section property data sets at non-rotating condition are quite similar to each other except for the natural frequency in the fourth flap mode. However, the natural frequencies using the predicted blade properties at nominal rotating condition are lower than those with the measured blade properties except for the second lead-lag frequency. The trimmed collective pitch control angle with the predicted blade properties is higher than both the wind-tunnel test data and the result using the measured blade properties in all the three test cases. The two different blade property data sets both give reasonable predictions on the blade section normal forces with BVI in the three test cases, and the two analysis results are reasonably similar to each other. The blade elastic deformations at the tip using the measured blade properties are correlated more closely with the wind-tunnel test data than those using the predicted blade properties in most correlation examples. In addition, the predictions of blade structural loads can be slightly or moderately improved by using the measured blade properties particularly for the oscillatory flap bending moments. Finally, the movement of the sectional centre of gravity location of the uninstrumented blade has a moderate influence on the blade elastic twist at the tip in the baseline case and the oscillatory flap bending moment in the minimum noise case.

The present comparison study on rotor aeromechanics analyses using the two different blade property data sets will show the influence of blade section properties on rotor aeromechanics analysis.

This paper is the first attempt to compare the aeromechanics analysis results using the two different blade section property data sets for all three test cases (baseline, minimum noise and minimum vibration) of HART-I in low-speed descending flight.

The purpose of this paper is to derive knockdown factor functions in terms of a shell thickness ratio (i.e. the ratio of radius to thickness) for conventional orthogrid and hybrid-grid stiffened cylinders for the lightweight design of space launch vehicles.

The shell knockdown factors of grid-stiffened cylinders under axial compressive loads are derived numerically considering various shell thickness ratios. Two grid systems using stiffeners – conventional orthogrid and hybrid-grid systems – are used for the grid-stiffened cylinders. The hybrid-grid stiffened cylinder uses major and minor stiffeners having two different cross-sectional areas. For modeling grid-stiffened cylinders with various thickness ratios, the effective thickness (t_eff) of the cylinders is kept constant, and the radius of the cylinder is varied. Thickness ratios of 100, 192 and 300 are considered for the orthogrid stiffened cylinder, and 100, 160, 200 and 300 for the hybrid-grid stiffened cylinder. Postbuckling analyses of grid-stiffened cylinders are conducted using a commercial nonlinear finite element analysis code, ABAQUS, to derive the shell knockdown factor. The single perturbation load approach is applied to represent the geometrical initial imperfection of a cylinder. Knockdown factors are derived for both the conventional orthogrid and hybrid-grid stiffened cylinders for different shell thickness ratios. Knockdown factor functions in terms of shell thickness ratio are obtained by curve fitting with the derived shell knockdown factors for the two grid-stiffened cylinders.

For the two grid-stiffened cylinders, the derived shell knockdown factors are all higher than the previous NASA’s shell knockdown factors for various shell thickness ratios, ranging from 100 to 400. Therefore, the shell knockdown factors derived in this study may facilitate in the development of lightweight structures of space launch vehicles from the aspect of buckling design. For different shell thickness ratios of up to 500, the knockdown factor of the hybrid-grid stiffened cylinder is higher than that of the conventional orthogrid stiffened cylinder. Therefore, it is concluded that the hybrid-grid stiffened cylinder is more efficient than the conventional orthogrid-stiffened cylinder from the perspective of buckling design.

The obtained knockdown factor functions may provide the design criteria for lightweight cylindrical structures of space launch vehicles.

Derivation of shell knockdown factors of hybrid-grid stiffened cylinders considering various shell thickness ratios is attempted for the first time in this study.

This paper aims to correlate the flexible multibody analysis for the performance, blade airloads, rotor pitch control angles, and blade structural loads of a full-scale utility helicopter rotor in low-speed forward flight with wind tunnel test and flight test data.

A nonlinear flexible multibody dynamics analysis code, DYMORE, is used to analyze the performance and aeromechanics of a utility helicopter rotor in low-speed forward flight. The main rotor system is modeled using various multibody elements such as rigid bodies, nonlinear elastic beams, mechanical joints, and elastic springs/dampers. The freewake model is used to capture rotor wakes more elaborately in low-speed forward flight.

Fair to good correlations of rotor performance such as figure of merit in hover, rotor power, propulsive force, and lift in low-speed forward flight are achieved with sweeps of the thrust, rotor shaft tilting angle, and advance ratio, against wind tunnel test data. The blade section normal forces from the mid-span to outboard are fairly or well correlated with flight test data, but the normal force at the inboard blade station is under-predicted. The trimmed pitch control angles are reasonably predicted; however, the lateral cyclic pitch control angle is moderately under-predicted. The flap bending moments are compared fairly with measurements; however, the oscillations of the lead-lag bending and torsion moments are not captured well.

Reasonable predictions of the performance and aeromechanics of the rotor in low-speed forward flight will allow the flexible multibody dynamics to be used for the rotorcraft comprehensive analysis, in place of expensive flight and wind tunnel tests of the rotor.

Up to now, the stand-alone flexible multibody dynamics without the aid of external aerodynamic analysis has not been widely used for the analyses of rotor performance and aeromechanics in low-speed forward flight. However, the present flexible multibody dynamics analysis directly integrated with the freewake model gives fair to good correlation of the rotor performance and aeromechanics predictions in low-speed forward flight.

The purpose of this paper is to examine the relationships among an individual athlete’s brand equity, overall spectator satisfaction at sporting events and behavioral intentions.

The convenience sampling method was used when approaching potential participants among spectators of the LG Whisen Rhythmic All Stars 2013, a sporting event in which celebrated sports players perform choreographed dance routines. A total of 350 surveys were completed in Go-Yang, South Korea. Of the surveys collected, 20 were discarded due to excessive missing values, resulting in 330 usable surveys.

Using structural equation modeling, this study found that the brand equity of an individual athlete positively and directly affects the overall sporting event satisfaction and behavioral intentions, including re-purchase and word-of-mouth intentions among event attendees, which are factors that are mediated indirectly by satisfaction.

This study shows that the brand equity of an individual athlete can increase the spectator satisfaction levels in a similar manner to the brand equity of a sports team or product.

This paper presents a case study on the problem of loading air containers in air express carriers motivated from DHL and Air Hong Kong. The problem is to determine the containers to be loaded and the locations of the loaded containers in an aircraft while maintaining stability of the aircraft. The objective of the problem is to maximize the revenue obtained from delivering containers. We present an integer programming model to represent and optimally solve the problem. Computational experiments done on a number of randomly generated test instances show that the integer program can be a viable tool for generating loading plans in the companies since optimal or near-optimal solutions for the test instances are obtained within a reasonable amount of computation time.

The Fourth Industrial Revolution ( 4th IR) affects the mode of company management. This paper aims to present a revised social responsibility (SR) model as an evaluation tool for corporate social responsibility (CSR) performance for sustainable organizational growth in the era of the 4th IR.

To develop an SR model that can be used well in the era of the 4th IR, the key references are “ISO 26000: Guidance on Social Responsibility” and the “Global Reporting Initiative (GRI) Guidelines.” For International Organization for Standardization (ISO) 26000 and the GRI guidelines, see the homepages in the References section. On the basis of these guidelines, a new SR model for sustainable development in the 4th IR is developed in this paper.

For a new SR model in the 4th IR, the concepts of management quality (MQ), quality responsibility (QR), creating shared value (CSV), social value and open data and open quality management are incorporated into the existing ISO 26000 evaluation criteria.

The 4th IR is changing the concepts of both quality management (QM) and SR. To the best of the authors’ knowledge, the new concept of SR has yet to be discussed extensively. In this paper, a new SR model is suggested to reflect the characteristics of the 4th IR.