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Optimal electron transfer with the catalyst through modulation of a graphene support with non-covalent adsorbents for achieving maximized activity and stability.

Purpose This study aims to examine the difference between personalized and non-personalized recommendations in influencing YouTube users’ video choices. In addition, whether men and women have a significant difference in using recommendations was compared and the predictors of recommendation video use frequency were explored. Design/methodology/approach A survey of 524 Saudi Arabia college students was conducted using computer-assisted self-administered interviews to collect their video recommendation sources and how likely they follow the recommendation from different sources. Findings Video links posted on social media used by the digital natives were found as the most effective form of recommendation shows that social approval is important in influencing trials. Recommendations can succeed in both personalized and non-personalized ways. Personalized recommendations as in YouTube recommended videos are almost the same as friends and family’s non-personalized posting of video links on social media in convincing people to watch the videos. Contrary to expectations, Saudi men college students are more likely to use recommendations than women students. Research limitations/implications The use of a non-probability sample is a major limitation and self-reported frequency may result in over- or under-estimation of video use. Practical implications Marketers will realize that they may not need the personalized recommendation from the large site. They can use social media recommendations by the consumers’ friends and family. E-mail is the worst platform for a recommendation. Social implications Recommendation is a credible source and can overcome the avoidance of advertising. Its influence on consumers will be increasing in years to come with the algorithmic recommendation and social media use. Originality/value This is the first study to compare the influence of different online recommendation sources and compare personalized and non-personalized recommendations. As recommendation is growing more and more important with algorithm development online, the study results have high reference values to marketers in Islamic countries and beyond.

Three-dimensional (3D) nanoarchitectures have offered unprecedented material performances in diverse applications like energy storages, catalysts, electronic, mechanical, and photonic devices. These outstanding performances are attributed to unusual material properties at the nanoscale, enormous surface areas, a geometrical uniqueness, and comparable feature sizes with optical wavelengths. For the practical use of the unusual nanoscale properties, there have been developments for macroscale fabrications of the 3D nanoarchitectures with process areas over centimeter scales. Among the many fabrication methods for 3D structures at the nanoscale, proximity-field nanopatterning (PnP) is one of the promising techniques that generates 3D optical holographic images and transforms them into material structures through a lithographic process. Using conformal and transparent phase masks as a key factor, the PnP process has advantages in terms of stability, uniformity, and reproducibility for 3D nanostructures with periods from 300 nm to several micrometers. Other merits of realizing precise 3D features with sub-100 nm and rapid processes are attributed to the interference of coherent light diffracted by phase masks. In this review, to report the overall progress of PnP from 2003, we present a comprehensive understanding of PnP, including its brief history, the fundamental principles, symmetry control of 3D nanoarchitectures, material issues for the phase masks, and the process area expansion to the wafer-scale for the target applications. Finally, technical challenges and prospects are discussed for further development and practical applications of the PnP technique.

To date, researchers have shown that nanostructured solid solutions of transition metal electrocatalysts can improve hydrogen evolution reaction (HER) activity in alkaline media. However, there are few reports that focus on mass producing efficient electrocatalysts for the HER based on continuous 3-dimensional (3D) nanopatterning. Herein, a 3D-nanopatterned solid solution of Ni–Mo is synthesized to provide efficient electrocatalytic activity in alkaline electrolytes. Experimentally, it is found that the electrochemically active surface area (ECSA) is 65 times higher than that of 2D Ni–Mo. Additionally, the charge transfer resistance (Rct) of 3D Ni–Mo (0.6 Ω) is 16 times lower than that of 2D Ni–Mo (10.3 Ω), which shows that 3D Ni–Mo allows the fast transport of ions and facilitates the H* desorption process; thus, the above result contributes to the improved kinetics for HER activity. Moreover, the 3D-nanopatterned Ni–Mo electrocatalyst requires a minimum overpotential of 39 mV to achieve a 10 mA cm−2 current density, which is very close to that of the benchmark Pt/C electrocatalyst (30 mV) for the HER in alkaline media. In addition, the 3D-nanopatterned Ni–Mo electrocatalyst exhibits 94.7% faradaic efficiency during the HER. The as-prepared 3D-nanopatterned Ni–Mo is a free-standing electrocatalyst that can be synthesized at the inch scale or even larger and will be useful for practical applications in future renewable energy devices.

This study examined the relationship between smartphones and ego integrity of older adults in South Korea. Retiree and older adult smartphone users were recruited from senior centres and community ...

Facial expressions are well known to change with age, but the quantitative properties of facial aging remain unclear. In the present study, we investigated the differences in the intensity of facial expressions between older (n = 56) and younger adults (n = 113). In laboratory experiments, the posed facial expressions of the participants were obtained based on six basic emotions and neutral facial expression stimuli, and the intensities of their faces were analyzed using a computer vision tool, OpenFace software. Our results showed that the older adults expressed strong expressions for some negative emotions and neutral faces. Furthermore, when making facial expressions, older adults used more face muscles than younger adults across the emotions. These results may help to understand the characteristics of facial expressions in aging and can provide empirical evidence for other fields regarding facial recognition.

To date, researchers have revealed that the electrocatalytic activity of 2-dimensional (2D) layered transition metal dichalcogenides (TMDCs) such as MoS2 can be improved by making free standing vertical structures to expose edge sites for efficient water splitting. However, poor electrical conductivity and structural instability restrict the practical application of vertical structures for efficient electrocatalytic activities. Here, a homogeneously attached MoS2 structure on well-ordered 3-dimensional nickel (3D-Ni) is reported for efficient hydrogen evolution reaction (HER). This homogeneously attached structure of MoS2 leads to abundant active sites and well-ordered 3D-Ni structures, solving the conductivity issue of MoS2 and ensuring the structural stability during electrocatalytic processes. By controlling the amount of MoS2 on the 3D-Ni, it is found that the electrochemical active area (ECSA) is increased by 5 times (50 cm2 of active sites) compared to normal MoS2 grown on 2D-Ni (9 cm2 of active sites). It is also found that the charge transfer resistance (Rct) of attached MoS2 structures on 3D-Ni (1 Ω) is 16 times lower than MoS2 grown on 2D-Ni (16 Ω). In addition, the proposed attached structure of MoS2 is stable in acidic electrolytes for continuous electrocatalytic activity and can be mass producible for practical applications.

The ability to express and recognize emotion via facial expressions is well known to change with age. The present study investigated the differences in the facial recognition and facial expression of the elderly (n = 57) and the young (n = 115) and measure how each group uses different facial muscles for each emotion with Facial Action Coding System (FACS). In facial recognition task, the elderly did not recognize facial expressions better than young people and reported stronger feelings of fear and sad from photographs. In making facial expression task, the elderly rated all their facial expressions as stronger than the younger, but in fact, they expressed strong expressions in fear and anger. Furthermore, the elderly used more muscles in the lower face when making facial expressions than younger people. These results help to understand better how the facial recognition and expression of the elderly change, and show that the elderly do not effectively execute the top-down processing concerning facial expression.

This study advances the protest paradigm as a transnational theory by examining how ideological affiliations within and across national borders influence the framing of a protest movement. Our empirical focus is the coverage of the 2016–17 South Korean ‘candlelight’ protests to oust conservative President Park Gyun-hye in Korean and US newspapers. Content analysis of 6 months of coverage suggests that liberal publications in both nations (Kyunghyang Shinmun and New York Times) were supportive of the movement, framing the protests as large yet peaceful and relying on protesters for information. In contrast, the conservative press in the US (Wall Street Journal) was closer in its coverage to Korea’s conservative publication (Chosun Ilbo), which was defensive of Park and her supporters. We argue that ideological affinities can operate beyond national boundaries – what we term ‘ideological parallelism’ – to make news organizations sympathetic or hostile toward a social movement. But nationalist sentiments also remain significant to the extent that a foreign (Korean) social movement affects a nation’s (US) foreign policy. We identify a novel framing device – Gaze – under which the coverage of both US newspapers converged and considered the adverse implications of candlelight protests for America’s relations with South Korea and its containment of North Korea and China. We also show how the US media’s Gaze recursively shapes South Korean press coverage, indicating that transnational protest frames impact local perceptions of social movements and can potentially influence their legitimacy and outcome.

Increasing the specific capacity and cycle life of graphitic carbon anodes is crucial for realizing high-performance lithium ion batteries. Herein, we introduce a new class of graphitic carbon anodes comprising highly ordered three-dimensional nanostructures decorated with SnO2 nanoparticles. The inch-scale, nanostructured graphitic carbon matrices are prepared by supported pyrolysis of epoxy templates patterned by advanced optical lithography. During the subsequent decoration process, the SnO2 nanoparticles are densely formed on the matrix without agglomeration since the periodic nanostructured matrix provides a homogeneous site for nucleation and growth. The surface coverage of the decorated SnO2 nanoparticles and the mass relative to the graphitic carbon are >80% and ∼50 wt%, respectively. The resulting nanostructured C/SnO2 composite monoliths can be assembled solely into LIB coin cells without the aid of binders and conducting agents. The achieved specific capacity and retention are 692 mAh g−1 and 87.31% (at 70th cycle), respectively, which is superior to those of nanostructured carbon anodes prepared in a similar way.

In recent years, two-dimensional black phosphorus (BP) has seen a surge of research because of its unique optical, electronic, and chemical properties. BP has also received interest as a potential thermoelectric material because of its high Seebeck coefficient and excellent charge mobility, but further development is limited by the high cost and poor scalability of traditional BP synthesis techniques. In this work, high-quality BP is synthesized using a low-cost method and utilized in a PEDOT:PSS film to create the first ever BP composite thermoelectric material. The thermoelectric properties are found to be greatly enhanced after the BP addition, with the power factor of the film, with 2 wt % BP (36.2 μW m–1 K–2) representing a 109% improvement over the pure PEDOT:PSS film (17.3 μW m–1 K–2). A simultaneous increase of mobility and decrease of the carrier concentration is found to occur with the increasing BP wt %, which allows for both Seebeck coefficient and electrical conductivity to be increased. Thes...

Purpose The purpose of this paper is to examine how college students’ social media use affects their school e-mail avoidance and campus involvement. Design/methodology/approach The study employed face-to-face interviews and self-administered survey/quantitative data. Findings Communication and business students are more involved on campus and likely to use social media as the primary communication medium than other majors. Social media and text messages are not the culprits of school e-mail avoidance. University departments, student organizations, and faculty advisors’ e-mails are most likely to be avoided. Social media users can be categorized as either “instant communicators” or “online content curators.” Facebook is the only social media brand conducive to campus involvement. Research limitations/implications This study only used one university’s students as sample. In examining school e-mail avoidance, it only focused on the source of e-mail. The study is limited by its sole reliance on quantitative behavioral data. Practical implications University administrators and academic advisors need to reconsider the e-mail communication to students, target at the instant communicator social media users, and use Facebook to create a strong sense of community and campus involvement for their students. Marketers can utilize the two social media user groups in selecting social media in targeting to students. Originality/value The study offered empirical evidence to explain how social media affect students’ school e-mail avoidance and the role of campus media and specific social media outlet on campus involvement. It advances the knowledge of media choice of students and the social media user groups.

This study explored the factors that may influence the viewership of online in-stream video advertising on YouTube, based on viewing context, viewing device, advertising appeals, video characterist...

ZnO is a potential thermoelectric material because of its non-toxicity, high thermal stability, and relatively high Seebeck coefficient (S) of metal oxides. However, the extremely low figure of merit (zT), which comes from a high thermal conductivity (κ) over 40 W m-1 K-1, limits the thermoelectric application of ZnO. In particular, below 500 K, ZnO exhibits a nearly negligible zT (

Enhancing the filler-to-matrix contact area by incorporating large graphene flakes (GFs) is considered a viable approach for improving the mechanical properties of polymer composites. Graphene oxide (GO) flakes have been initially pursued for this application owing to the advantage of producing large-sized GFs. However, the defective nature of GO makes it technically challenging to precisely assess their dimensional effect on resulting mechanical properties, limiting their versatility as reinforcing materials. Therefore, it is highly desired to fabricate GFs with minimum defects and large lateral size. In this paper, we report the fabrication of high-quality edge functionalized non-oxidized graphene flakes (f-NOGFs) by the liquid exfoliation of graphite intercalation compounds. As-prepared f-NOGFs are over 1 μm in lateral size and contain less than 6.25% of impurity oxygen. By using size-sorted f-NOGFs, we systematically studied the relationship between mechanical properties and lateral sizes in f-NOGFs-incorporated epoxies. We identify that epoxy composites containing 0.6 wt% of f-NOGFs with a lateral size of 1 μm present outstanding mechanical properties; elastic modulus of 3.65 GPa, ultimate tensile strength of 95.74 GPa and toughness of 2.52 MJ m−3. The study presented in this paper could provide better understanding for optimization of the mechanical reinforcement of graphene-polymer composites.

The selective reduction of thermal conductivity while preserving the Seebeck coefficient and electrical conductivity is regarded as a key strategy for achieving the high dimensionless figure-of-merit (ZT) of thermoelectric materials. Here, we newly propose a periodic three-dimensional (3D) nanostructure that has an ability to significantly reduce thermal conductivity, resulting in an improved ZT value of thermoelectric materials near room temperature. A 3D nanostructured thermoelectric monolith is developed by electrochemical deposition of a Bi–Sb–Te ternary alloy into a highly ordered, interstitial porous network in an epoxy template predefined by advanced lithography. The resultant inch-scale, bicontinuous nanocomposite monolith released from a substrate can be easily transferred to a customized reliable platform for evaluating thermoelectric properties. The measured thermal conductivity is only ∼0.89 W mK−1 at 350 K due to greatly increased phonon boundary scattering without any degradation in the Seebeck coefficient and electrical conductivity, leading to an enhanced ZT value (∼0.56) which is ∼50% higher than that of an ordinary film with the same elemental composition. The 3D nanostructure developed here will provide new design opportunities for nanostructured thermoelectric materials, potentially usable in flexible thermoelectric coolers and wearable energy harvesting systems.

This paper makes an attempt to call attention and point to the importance of Manchu historical records, but at the same time warns against the pitfalls of uncritical utilisation of these historical sources (the possibility of falsification and the fabrication of historical material). The authors focus on volume 20 of the 親征平定朔漠方略 Qinzhengpingdingshuo-mofanglue (Beye dailame wargi amargi babe necihiyeme toktobuha bodogon i bithe. orici debtelin) written in Manchu. This Manchu historical document is of prime importance in the historical enquiry of the period. It gives a clear picture of the military strategy of the time and provides accurate facts concerning the exact names of persons and places, the system of administration, wartime munitions mobilisation, and much more.

Density-strength tradeoff appears to be an inherent limitation for most materials and therefore design of cell topology that mitigates strength decrease with density reduction has been a long-lasting engineering pursue for porous materials. Continuum-mechanics-based analyses of mechanical responses of conventional porous materials with bending-dominated structures often give the density-strength scaling law following the power-law relationship with an exponent of 1.5 or higher, which consequentially determines the upper bound of the specific strength for a material to reach. In this work, a new design criterion capable of significantly abating strength degradation in lightweight materials is presented, by successfully combining the size-induced strengthening effect in nanomaterials with the architectural design of cellular porous materials. Hollow-tube-based 3D ceramic nanoarchitectures satisfying such criterion are fabricated in large area using proximity field nano-patterning and atomic layer deposition. Experimental data from micropillar compression confirm that the strengths of these nanoarchitectural materials scale with relative densities with a power-law exponent of 0.93, a hardly observable value in conventional bending-dominated porous materials. This discovery of a new density-strength scaling law in nanoarchitectured materials will contribute to creating new lightweight structural materials attaining unprecedented specific strengths overcoming the conventional limit.

This article reviews the characteristics of terms used by the Mongols to express taboos concerning food and examines their food-related culture based on sources from the Mongolian Empire (Plano Carpini’s Historia Mongalorum, Marco Polo’s Il milione, Chinggis Khan’s Yeke Jasag, Rashīd ad-Dīn’s Jāmiʿ al-tawārīkh, and the Yuan Dynasty’s 飮食須知 Yin shi xu zhi). The Mongols left behind fairly strict food-related taboos in the form of eating habits. To better understand Mongolia’s food-related taboo expressions, we have examined five mediaeval sources written in various languages in which diverse food taboos are recorded.

The Bereitschaftspotential (BP) is a slow negative cortical potential preceding voluntary movement. Since movement preparation is dependent upon the synchronous activity of a variety of neurons, BP may develop through the exchange of information among motor-related neurons. However, the relationship between BP and information flow is not yet well-known. In the present study, we aimed to investigate how the connectivity in the prefrontal cortex (PFC) changes during the occurrence of BP. Electrocorticography (ECoG) was recorded in five patients with epilepsy. The subjects performed self-paced hand grasping. We compared the intraregional connectivity between PFC and non-PFC regions using partial directed coherence. In the PFC, the connectivity of beta and gamma bands in the BP period increased by an average of 24.4% compared with the baseline connectivity. Conversely, gamma connectivity in non-PFC regions decreased by 31.4%. Moreover, the intraregional connectivity in the PFC increased according to the stage of BP. The increased gamma band connectivity in the PFC implies that the increased communication among neurons in the PFC is associated with development of BP. Intraregional connectivity as one of the factors involved in voluntary movement may reflect the activation of brain networks related to movement preparation in PFC.

Functional nanocomposites have attracted great attention in a variety of fields of application including energy harvesting (or storage) devices, structural materials, heat-dissipating materials and many others due to their controllable material properties (e.g., mechanical, thermal, electrical, and optical). However, conventional solid or porous nanocomposites based on nanoparticle-type materials have significant problems such as a high aggregation tendency, low percolation ratio and low mass transport, which cause a fatal degradation of the mechanical, thermal and electrical performance. Therefore, here we focus on unconventional nanocomposites using 3D continuous and ordered nanostructures to overcome the aforementioned issues. The 3D ordered and continuous nanostructures ensure excellent dispersion, conduction and efficient mass transport properties, resulting in outstanding material properties of functional nanocomposites. In this review, useful fabrication techniques of the 3D functional nanocomposites using proximity-field nanopatterning, which is a reliable 3D patterning tool over a large area, will be summarized. Furthermore, we will introduce the 3D functional nanocomposite-based high-performance applications including a functional coating film, stretchable conductor, strain sensor and lithium ion battery.

Modelling of the force transmitted through vibration isolation elements in terms of the displacement and the velocity is very useful in transfer path or vibration power analysis of dynamic systems. Modelling using the complex stiffness in the frequency domain can be a good solution for linear elements, and force-state mapping can be a good solution for non-linear elements. In this study, it is noted that conventional force-state mapping with a linear part simply consisting of a linear spring and a viscous damper does not work sufficiently well for vibration isolation elements typically made of rubber materials; therefore, modelling of the linear part using the complex stiffness is proposed. The non-linear force-state model with the complex stiffness model for the linear part is applied to a set of simulation data for validation of the proposed approach and to another set of data measured from a cabin mount of an excavator for illustration. A form of the fractional polynomial function of the frequency is utilized for curve fitting of the linear complex stiffness in the frequency domain. The constraints for stability and causality on the coefficients and the order of this form are discussed. Procedures for the construction of the whole model are presented. Based on the modelling of the simulated and measured data, it is claimed that the suggested modelling is promising as a representation of the frequency- and amplitude-dependent complex stiffness of vibration isolation elements.

Various models of a seated human body have been developed in the literature so far based on measurements of apparent mass in the vertical Z -direction alone or fore-and-aft X -direction alone. As the authors observed that accelerations in both X and Z directions are equally significant in tests on an excavator working in a quarry, 3×3 apparent inertia matrix was experimentally obtained as functions of frequency by exciting the seated human body in the Z – X plane, i.e. providing two translational motions in the Z and X axes and one angular motion about the Y -axis. A subject in slightly slouched posture was sitting on a seat without backrest and the hands were on lap. Five resonances were found in the frequency range of interest, i.e. up to 20 Hz, below 1 Hz and at 3, 5.25, 8, 9.5 Hz, which is one more than four resonances found in previous researches. The resonance at 8 Hz was newly found in only pitch component of the apparent inertia matrix. Since the experiment was carried out only for one subject, it may not be guaranteed that the new resonance is generally applicable. A 5-degree-of-freedom (dof) model with 23 parameters is proposed for the description of the apparent inertia matrix of a seated human body. The 8 geometric parameters were included in the model in order to describe the couplings between coordinates. The model yielded the resonances at 0.61, 3.3, 5.1, 8.8 and 9.8 Hz, which are near to observations of the experiment. The parameters of the models may not necessarily represent the physical values of a human body because only the apparent inertia matrix at human body–seat interface was reflected. The model may not be perfect because the apparent inertia matrix was obtained from only one subject. Yet, the observations and the model in this research could be a guideline or reference in future researches to obtain more perfect models. Since the vibration responses in the Z – X plane at the human–seat interface can be predicted using the proposed 5-dof model, this model could be used for evaluation of a seat system by computer simulations from the aspect of ride comfort and health.

In general, three-dimensional ground reaction forces (GRFs) and ground reaction moments (GRMs) that occur during human gait are measured using a force plate, which are expensive and have spatial limitations. Therefore, we proposed a prediction model for GRFs and GRMs, which only uses plantar pressure information measured from insole pressure sensors with a wavelet neural network (WNN) and principal component analysis-mutual information (PCA-MI). For this, the prediction model estimated GRFs and GRMs with three different gait speeds (slow, normal, and fast groups) and healthy/pathological gait patterns (healthy and adolescent idiopathic scoliosis (AIS) groups). Model performance was validated using correlation coefficients (r) and the normalized root mean square error (NRMSE%) and was compared to the prediction accuracy of the previous methods using the same dataset. As a result, the performance of the GRF and GRM prediction model proposed in this study (slow group: r = 0.840–0.989 and NRMSE% = 10.693–15.894%; normal group: r = 0.847–0.988 and NRMSE% = 10.920–19.216%; fast group: r = 0.823–0.953 and NRMSE% = 12.009–20.182%; healthy group: r = 0.836–0.976 and NRMSE% = 12.920–18.088%; and AIS group: r = 0.917–0.993 and NRMSE% = 7.914–15.671%) was better than that of the prediction models suggested in previous studies for every group and component (p

3D interference printing enables the single-step production of multilayered ultralong nanochannel arrays with nanoscale regularity. The superior depth-of-focus of this technique realizes a state-of-the-art nanostructure which has intensively stacked 32 layers of inch-long, horizonontal nanochannels with sub-100 nm holes in a monolithic matrix (≈15 μm). This exceptional structure can be integrated into microfluidic devices, facilitating high-flux rheological platforms using nanocapillarity.

Body-on-frame type vehicle has a set of frame bushes between body and frame for vibration isolation. Such frame bushes are important vibration transmission paths to passenger space for excitations during driving. In order to reduce the vibration level of passenger space, therefore, change of complex stiffness of the frame bushes is more efficient than modification of other parts of the vehicle such as body, frame and suspension. The purpose of this study is to reduce the vibration level for ride comfort by optimization of complex stiffness of frame bushes. In order to do this, a simple finite element vehicle model was constructed and complex stiffness of the frame bushes was set to be design variables. The objective function was defined to reflect frequency dependence of passenger ride comfort. Genetic algorithm and sub-structure synthesis were applied for minimization of the objective function. After optimization level at a position of interest on the car body was reduced by about 43.7 % in RMS value. Causes for optimization results are discussed.

軟毛なブラシでアブラカンギクにブラッシング処理を行った．処理回数は1日10回，20回，30回で，処理期間は15日行った実験区，または，処理期間は7日，14日，21日で，1日の処理回数は15回に設定した実験区を設けた．草丈はすべての処理区で処理後26日目，顕著に抑制されたが，処理停止後，時間の経過とともにわい化効果は減少した．草丈は15回21日処理区で最も抑制された．分枝長と葉面積はすべての区で抑制された．分枝数は，15回21日処理区と30回14日処理区で増加した．茎と根の新鮮重と乾物重はブラッシング処理によって減少した．クロロフィル含量は，影響が認められなかった．気孔数は，15回21日処理区で最も多くなった．気孔の幅は小さくなったが，気孔の長さには影響が認められなかった．発蕾開始日は，15回21日処理区で6日早まり，花数は増加した．開花数は30回14日と15回21日処理区で増加した．本実験からは品質の高いアブラカンギクの鉢物を生産するには毎日5回21日のブラッシング処理が適当と思われた．

Due to an efficient interconnect structure and internal parallelism, partitioned-bus architecture is viable for deep sub-micron chip design. In this paper, we propose a new partitioned-bus architecture and its supporting high-level synthesis methodology. The new architecture extends an existing linear architecture by stacking multiple layers for handling large datapath intensive applications. Experiments show that the approach generates compact datapath layout with flexibility of aspect ratio and reduces average bus driving length.

Most circuits contain a number of multiplexers. An n-to-1 multiplexer is generally implemented by decomposition into 2-to-1 multiplexer. Due to its ordered tree structure, the n-to-1 multiplexer decomposition problem can be relatively easily solved for minimizing design considerations such as timing, area, and power consumption. In this paper, we propose an efficient and accurate method for estimating the number of signal transitions in multiplexer tree and a low-power multiplexer decomposition method using the proposed estimation method without any change of boolean functions of selection signals. The decomposition method is a kind of re-engineering method. Experimental results show that our proposed method can accurately estimate the number of internal signal transitions and their propagations, and our optimization technique using the proposed method reduces power consumption by considerable amount in multiplexer trees.