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With the spread of the Internet, e-learning which is a way of learning using information technology has become popular. Although lecture videos in e-learning are designed so that many learners can understand, they do not take into consideration individual differences of learners. To address this problem, we designed a system that can grasp the concentration state of learners using electroencephalogram and dynamically provide contents according to the state. Moreover, we defined a metric using alpha waves in brain waves acquired from the occipital region as an index of changing learning materials used in the system. It enables providing suitable contents to each learner. In this research, we investigated the usefulness of the index and compared it with other brain waves such as theta waves and beta waves. As a result, it was confirmed that the proposed index was useful to extract learners who are relatively concentrating and not relatively concentrating. Moreover, it was suggested that alpha waves were more useful as the index for concentrating state than other waves.

This paper deals with map-construction problems for visual localization. Basically, the map is an aggregation of visual landmarks, and it is desirable that such landmarks exist densely and permanently for long-term localization. However, there are no landmarks with these attributes at the same time. In order to solve this problem, we propose a hybrid map with permanent landmarks and temporal landmarks. As a permanent landmark, we employ 3D wireframe which can be easily obtained from architectural CAD. For a temporal landmark, we use line segments which are visually detected in images captured by a camera. To handle these two types of landmarks on the same map, we develop two algorithms. One is to extract temporal line segments from images containing two mixed landmarks, and the other is to reconstruct them into the 3D wireframe map. We experimentally demonstrated that the proposed hybrid map outperformed the 3D wireframe map in terms of localization accuracy.

On-surface chemical reactions provide an attractive route for making tailored nanostructures. Here the authors present a thermally-controlled sequential on-surface transformation of a hydrocarbon molecule, characterized via high-resolution atomic force microscopy and density functional theory calculations.

In order to reduce a road monitoring cost, we propose a system to monitor extensively road condition by cyclists with a smartphone. In this paper, we propose two methods towards road monitoring. First is to classify road signals to four road conditions. Second is to extract road signal from a smartphone's accelerometer in three positions: pants' side pocket, chest pocket and a bag in a front basket. In pants' side pocket, road signal is extracted by Independent Component Analysis. In chest pocket and bag in a front basket, road signal is extracted by selecting 1-axis affected from gravitational acceleration. In the experiment of the classification method, overall accuracy was 75%. The experimental results of the extraction methods with correlation coefficient showed the overall accuracy were more than 0.7 in pants' side pocket and chest pocket, the overall accuracy was less than 0.3 in bag in a front basket.

Temperature in an urban area exhibits a complicated pattern due to complexity of infrastructure. Despite geographical proximity, structures of a group of buildings and streets affect changes in temperature. To investigate the pattern of fine-grained distribution of temperature, we installed a densely distributed sensor network called UScan. In this paper, we describe the system architecture of UScan as well as experience learned from installing 200 sensors in downtown Tokyo. The field experiment of UScan system operated for two months to collect long-term urban temperature data. To analyze the collected data in an efficient manner, we propose a lightweight clustering methodology to study the correlation between the pattern of temperature and various environmental factors including the amount of sunshine, the width of streets, and the existence of trees. The analysis reveals meaningful results and asserts the necessity of fine-grained deployment of sensors in an urban area.

Rotaxanes consisting of achiral axle and achiral ring components can possess supramolecular chirality due to their unique geometrical architectures. To synthesize such chiral rotaxanes, we adapted a prerotaxane method based on aminolysis of a metacyclophane type prerotaxane that had planar chirality, which is composed of an achiral stopper unit and a crown ether type ring component. The prerotaxanes were well resolved using chiral HPLC into a pair of enantiomerically pure prerotaxanes, which were transferred into corresponding chiral rotaxanes, respectively. Obtained chiral rotaxanes were revealed to have considerable enantioselectivity.

This paper describes an autonomous deployment and restoration of a Wireless Sensor Network (WSN) using mobile robots. The authors have been developing an information-gathering system using mobile robots and WSNs in underground spaces in post-disaster environments. In our system, mobile robots carry wireless sensor nodes (SN) and deploy them into the environment while measuring Received Signal Strength Indication (RSSI) values to ensure communication, thereby enabling the WSN to be deployed and restored autonomously. If the WSN is disrupted, mobile robots restore the communication route by deploying additional or alternate SNs to suitable positions. Utilizing the proposed method, a mobile robot can deploy a WSN and gather environmental information via the WSN. Experimental results using a verification system equipped with a SN deployment and retrieval mechanism are presented.

Self-assembly of molecular building blocks into two-dimensional nanoporous networks has been a topic of broad interest for many years. However, various factors govern the specific outcome of the self-assembly process, and understanding and controlling these are key to successful creation. In this work, the self-assembly of two alkylated dehydrobenzo[12]annulene building blocks was compared at the liquid-solid interface. It turned out that only a small chemical modification within the building blocks resulted in enhanced domain sizes and stability of the porous packing relative to the dense linear packing. Applying a thermodynamic model for phase transition revealed some key aspects for network formation. [ABSTRACT FROM AUTHOR]

Weak van der Waals adsorption of π-conjugated hydrocarbon molecules onto the gold surface, Au(111), is one of the essential processes in constructing organic-metal interfaces in organic electronics. Here we provide a first direct observation of adsorption geometry of a single π-conjugated hydrocarbon molecule on Au(111) using an atomically resolved scanning tunneling microscopy study combined with van der Waals density functional methodology. For the purpose, we utilized a highly symmetric π-conjugated hydrocarbon molecule, dehydrobenzo[12]annulene (DBA), which has a definite three-fold symmetry, the same as the Au(111) surface. Interestingly, our observations on an atomically resolved scale clearly indicate that the DBA molecule has only one adsorption configuration on Au(111) in spite of the weak van der Waals adsorption system. Based on the precisely determined adsorption geometry of DBA/Au(111), our calculation results imply that even a very small contribution of the interfacial orbital interaction at the organic-metal interface can play a decisive role in constraining the adsorption geometry even in the van der Waals adsorption system of a π-conjugated hydrocarbon molecule on the noblest Au(111) surface. Our observations provide not only deeper insight into the weak adsorption process, but also new perspectives to organic electronics using π-conjugated hydrocarbon molecules on the Au surface. [ABSTRACT FROM AUTHOR]

In recent years, we have witnessed a new trend of learning called e-learning where learners can take courses using electronic devices with Internet connection. Although e-learning is convenient because it removes temporal and spatial limitations, it is difficult to know whether the learner is really paying attention to the learning materials. To address this problem, we tried to use electroencephalography (EEG) to investigate a learner's concentration in our previous study. However, our previous study relied on subjective evaluation, and there was no objective observation to relate the EEG signals to the learner's concentration. Given this background, we compared eye gaze and EEG results to find the appropriate position and frequency band of EEG in e-learning in this study. We compared the EEG result obtained during a period when the subjects were watching a video lecture and that obtained during a period when the subjects were not watching, and determined that the viewing state could be predicted from EEG logistic regression and a support vector machine (SVM). The results suggested that measuring beta and gamma waves and examining the parietal and occipital regions are both effective. [ABSTRACT FROM AUTHOR]

Increased sensitivity is seen in strained (n)cyclophanes, which are subjected to rare interactions in electrophilic interactions. The aromatic ring undergoes a strain which is characterized by incorporation and reorganization interactions. The early stage of the interactions omit these strains in substantial quantities. Transition-state energy is reduced by enhanced HOMO levels. Nucleophilic interactions with increased reactivity are exhibited by strained cyclophanes due to strain emissions. LUMO level nucleophilic replacement is seen in 8,11-dihalo-substituted (5)metacyclophanes, which are the tiniest isolable (n)metacyclophane products. Powerful classes which withdraw electrons do not metabolize the products, although the interaction occurs in a gentle environment.

A polycyclic aromatic hydrocarbon having a twisted cyclooctatetraene (COT) core was prepared by a formal [4+4] dimerization of an in situ generated indeno[2,1-a]fluorene derivative. The compound consists of two indenofluorene frameworks connected with two double bonds and adopts a twisted geometry to avoid intramolecular steric repulsion. It exhibits a long-wavelength absorption band with a maximum at 634 nm extending to about 850 nm, which is consistent with the moderate antiaromaticity of the twisted COT ring as indicated by the NICS value (+11.9). A mechanism for cycloaddition reaction is proposed in terms of stepwise bond formations due to the diradical character of the indenofluorene framework, on the basis of the completely different reaction product obtained from the extended benzo analogue. [ABSTRACT FROM AUTHOR]

Anthracenophanes instantly undergo air oxidation, although the central aromatic ring of its compounds is only a little deformed from planarity. This is in contrast to the benzolog, paracyclophane. Also H NMR spectrum of the anthracenophane derivative at 30 degrees Celsius shows three signals for methylene protons, revealing that the flipping of methylene bridge is faster on the NMR time scale. As the temperature is lowered, the signals broaden, thus enabling methylene proton to appear at delta-1.89 parts per million at -90 degrees Celsius.

A correlation between the enantiorecognitive coloration of indicator 1, and the complementarity defined by the association constants including the CPK modeling, has been established. Quinone hydrazone-azophenol tautomerization from optically pure 1-phenyl-cis-1,2-cyclohexanediol with a known absolute configuration, protection of the diol with CH2(OCH3)2, etherification with diethylene glycol ditosylate/NaH, deprotection, cyclization with 1, 4-dimethoxy-2,6-bis(bromomethyl)benzene and oxidation with ceric ammonium nitrate and 2,4-dinitrophenylhydrazonation, were used to synthesize two enantiomeric chiral acerands.

We present a systematic scanning tunneling microscopy study on the 2D self-assembly of pentagonal shaped macrocycles at the liquid/solid interface to gain insight about 2D pentagonal molecular crystallization. Macrocycles with alkyl ester groups form an anti-parallel type linear pattern mainly viafavorable intermolecular interactions between the interdigitated alkyl chains at the 1,2,4-trichlorobenzene (TCB)/graphite interface. On the other hand, at the TCB/Au(111) interface, they showed a random pattern and an anti-parallel type linear pattern. The selection between both motifs is ascribed to the balance between the intermolecular and molecule–substrate interactions. Most interestingly, the parent molecule forms dense anti-parallel and parallel linear patterns reflecting the intrinsic pentagonal core shape. Moreover, bright and mobile spots were often observed in the networks to occupy free spaces, including the cavity of the macrocycles, which we attribute to a co-adsorbed solvent molecule or Au ion. [ABSTRACT FROM AUTHOR]

A self-assembled monolayer of a mixture of radical 2,3,7,8,12,13,17,18-octaethylporphyrin (OEP)TbIII double-decker (TbIII(OEP)2) single-molecule magnets and alkoxylated dehydrobenzo[12]annulene (DBA) at the 1-phenyloctane/highly oriented pyrolytic graphite interface was investigated using scanning tunneling microscopy. The observations revealed that single TbIII(OEP)2 molecules were incorporated in the 2D pores of the honeycomb structure formed by a DBA derivative containing octyloxy chains. The number of TbIII(OEP)2 molecules coadsorbed in the porous DBA networks increased with increasing concentration of the TbIII(OEP)2 radical solution. [ABSTRACT FROM AUTHOR]

Treatment of octadehydrotribenzo[14]annulene ([14]DBA) with bromine or iodine gave the corresponding tetrahalo-substituted benzodiindenocyclooctatetraenes selectively via tandem twofold transannular bond formations. The exclusive mode of cyclization in contrast to that observed for the nucleophile-induced cyclizations is interpreted in terms of the relative stabilities of the key intermediates in both processes. [ABSTRACT FROM AUTHOR]

Tris-(2-hydroxybenzylidene)triaminoguanidinium salts having six alkyl chains with proper spacing served as new molecular building blocks for the formation of porous honeycomb networks by van der Waals interaction between interdigitated alkyl chains at the liquid/graphite interfaces. [ABSTRACT FROM AUTHOR]

We present here the formation of giant pores in surface-confined molecular networks of a triangular-shaped dehydrobenzo-[12]annulene derivative: the diameter of the pores reaches over 7 nm and the giant pores are used as templates to accommodate a giant molecular spoked wheel, which allows us to observe rotational and adsorption–desorption dynamics of single guest molecules. [ABSTRACT FROM AUTHOR]

3,3'-Disubstituted 2,2'-binaphthyls were prepared by the Cu- or Re-catalyzed double benzannulation reaction of 2-(phenyl-ethynyl) benzaldehyde with various butadiynes in the presence of trichloroacetic acid, in moderate to good yields. Acceleration of the second benzannulation was clearly observed. [ABSTRACT FROM AUTHOR]

The article presents a study on site-selective guest inclusion in molecular networks of butadiyne-bridged pyridino and benzeno square macrocycles on a surface. It states that alignment of functional molecules on two-dimensional (2D) molecular networks on solid surfaces is of current concern owing to possible nanotechnological applications, like the fabrication of molecular scale devices and machines.