Quantum dots (QDs) are an attractive material for application in solar energy conversion devices because of their unique properties including facile band-gap tuning, a high-absorption coefficient, low-cost processing, and the potential multiple exciton generation effect. Recently, highly efficient quantum dot-sensitized solar cells (QDSCs) have been developed based on CdSe, PbS, CdS, and Cu-In-Se QDs. However, for the commercialization and wide application of these QDSCs, replacing the conventional rigid glass substrates with flexible substrates is required. Here, we demonstrate flexible CISe QDSCs based on vertically aligned TiO2 nanotube (NT) electrodes. The highly uniform TiO2 NT electrodes are prepared by two-step anodic oxidation. Using these flexible photoanodes and semi-transparent Pt counter electrodes, we fabricate the QDSCs and examine their photovoltaic properties. In particular, photovoltaic performances are optimized by controlling the nanostructure of TiO2 NT electrodes

Trogoderma variabile B. is one species of well-known stored product insect. This study was conducted to test the perforation ability of larvae of T. variabile on different packaging films which has been widely used in food industry at different thickness. The tested packaging films are polypropylene (PP) 20μm, low density polyethylene (LDPE) 20μm, polyethylene terephthalate (PET) 12μm, PP 30μm and PP 40μm. This investigation was carried out for 7 days. In the same order as the films mentioned above, the perforation rate are 33.33%, 0%, 14.81%, 29.62%, 0%. From these results, the easiest film to perforate among PP, LDPE, PET is PP, and there are significant differences on thickness. Therefore, different type of materials and thickness would be considered to be used for food packaging.

Nitrogen is a serious contaminant in natural gas because it decreases the energy density. The natural gas specification in South Korea requires a N2 content of less than 1 mol%. Thus, cost-effective N2 removal technology from natural gas is necessary, but until now the only option has been energy-intensive processes, e.g., cryogenic distillation. Using porous materials for the removal process would be beneficial for an efficient separation of CH4/N2 mixtures, but this still remains one of the challenges in modern separation technology due to the very similar size of the components. Among various porous materials, metal-organic frameworks (MOFs) present a promising candidate for the potential CH4/N2 separation material due to their unique structural flexibility. A MIL-53(Al), the most well-known flexible metal-organic framework, creates dynamic changes with closed pore (cp) transitions to open pores (ops), also called the ‘breathing’ phenomenon. We demonstrate the separation performance of CH4/N2 mixtures of MIL-53(Al) and its derivative MIL-53-NH2. The CH4/N2 selectivity of MIL- 53-NH2 is higher than pristine MIL-53(Al), suggesting a stronger CH4 interaction with NH2.

This paper proposes a fusion controller combing an anti-windup PID controller and BELBIC (Brain Emotional Learning Based Intelligent Controller) for controlling the position and vibration of a robot system having a single flexible manipulator. A finite element model of the flexible manipulator is developed. The reliability of it is verified by comparing the natural frequencies computed using the finite-element method with the experimentally measured ones. An MSC.ADAMS computational model of the robot system is interfaced with the proposed controller in MATLAB/Simulink, for carrying out a simulation. The simulation is performed with various references inputs and endpoint masses. The effectiveness and robustness of the proposed controller for control of the position and vibration of the flexible manipulator is shown through the simulation.

Free-standing electrodes of CuO nanorods in carbon nanotubes (CNTs) are developed by synthesizing porous CuO nanorods throughout CNT webs. The electrochemical performance of the free-standing electrodes is evaluated for their use in flexible lithium ion batteries (LIBs). The electrodes comprising CuO@CNT nanocomposites (NCs) were characterized by charge-discharge testing, cyclic voltammetry, and impedance measurement. These structures are capable of accommodating a high number of lithium ions as well as increasing stability; thus, an increase of capacity in long-term cycling and a good rate capability is achieved. We demonstrate a simple process of fabricating free-standing electrodes of CuO@ CNT NCs that can be utilized in flexible LIBs with high performance in terms of capacity and cycling stability.

The stereotype of flexible MOFs(Amino-MIL-53) and carbonized porous carbon prepared from renewable resources is successfully synthesized for CO2 reduction application. The textural properties of these microporous materials are investigated, and their CO2 storage capacity and separation performance are evaluated. Owing to the combined effects of CO2-Amino interaction and its flexibility, a CO2 uptake of 2.5 mmol g−1 is observed in Amino-MIL-53 at 20 bar 298 K. In contrast, CH4 uptake in Amino-MIL-53 is very low up to 20 bar, implying potential sorbent for CO2/CH4 separation. Carbonized samples contain a small quantity of metal residues(K, Ca, Mg, S), resulting in naturally doped porous carbon. Due to the trace metal, even higher CO2 uptake of 4.7 mmol g−1 is also observed at 20 bar 298 K. Furthermore, the CH4 storage capacity is 2.9 mmol g−1 at 298 K and 20 bar. To evaluate the CO2 separation performance, the selectivity based on ideal adsorption solution theory for CO2/CH4 binary mixtures on the presented porous materials is investigated.

Recent developments in the field of energy harvesting technology that convert ambient energy resources into electricity enable the use of self-powered energy systems in wearable and portable electronic devices without the need for additional external power sources. In particular, piezoelectric-effect-based flexible energy harvesters have drawn much attention because they can guarantee power generation from ubiquitous mechanical and vibrational movements. In response to demand for sustainable, permanent, and remote use of real-life personal electronics, many research groups have investigated flexible piezoelectric energy harvesters (f-PEHs) that employ nanoscaled piezoelectric materials such as nanowires, nanoparticles, nanofibers, and nanotubes. In those attempts, they have proven the feasibility of energy harvesting from tiny periodic mechanical deformations and energy utilization of f-PEH in commercial electronic devices. This review paper provides a brief overview of f-PEH devices based on piezoelectric nanomaterials and summarizes the development history, output performance, and applications.

Road network in the Mekong Delta is mostly coastal and river routes, then they are often flooded when the floods come in. As a result, the foundation and pavement are destroyed, reduced life expectancy, resulting in unsafety in traffic, cost of maintenance and repairs…. This paper establishes the technical conditions for the calculation on the flexible pavement working in the wet conditions (so flooded) based on the maximum usage of available materials in the provinces in the Mekong Delta. Simultaneously, we propose the flooded flexible pavement under the current climate change conditions.

Recently, composite beams have been developed in which concrete is filled in a U-shaped steel plate for saving height of story. And due to high flexural stiffness and bending strength, it is widely applied in the field where high load and long span are required. The AU composite beam was improved the instability of the existing beams because it makes a closed section by attaching a cover type shear connection to the existing U - shaped composite beam with open upper section. In this study, AU composite beam resisted by composite-section during the using phase was evaluated the safety through the finite element analysis. The analysis is performed on the five specimens of AU composite beams according to applied deck-system and compared with the results of 2 - point bending test. As a result of the analysis, behavior of beam was shown by integrated composite section. And the evaluation of flexible capacity was p

Due to dramatic changes in the trend of corporate management in economics, labor and government, companies are being asked to adapt creative and innovative organizational culture in order to keep sustainability. Under the circumstances, flexible working hour becomes one of very effective method for organization culture improvement. Recently, M company has introduced the new policy of working hours that employees can choose a couple of different time options depending on their personal situations. And it turns out to be very effective to work & life balance, increasing organizational vitality, improving efficiency of business and productivity, recruitment of core human resources, and prevention of deviation; both team and personal performance levels has significantly improved. Therefore, it is highly recommended to adapt flexible working policies for companies seeking for a long term, sustainable corporate vision.

본 연구에서는 각기 다른 두 제조사의 AgNW를 활용하여 스핀코팅 속도, 열처리 온도 및 방법 그리고 PDMS코팅 속도에 따른 AgNW/PDMS composite공정 연구를 실시하였다. 실험결과 peel off 특성에 영향을 미치는 인자로 건조방식이 주요하게 작용하며 공정온도 또한 전극 특성에 영향을 주었다. 핫플레이트를 사용한 건조방식은 한방향 열전달로 인해 PDMS를 충분히 건조시키지 못하였지만 오븐 건조를 통해 그 결점을 보완할 수 있었다. 또한, PDMS 코팅속도가 증가함에 따라 스트레처블 특성이 향상되었고 GF는 0.03에서 0.07로 약 100정도 향상되었다.

PURPOSES : One of the main components of road projects funded by the Economic Development Cooperation Fund (EDCF) is the improvement or rehabilitation of existing pavements. The result is that pavement structures are critical to the success of a project. There is, however, no design standard available at present that reflects a region's specific features including climate conditions and quality of pavement materials. For this reason, a comparative study of the major EDCF borrowers' flexible pavement design standards was conducted. This study led to the proposal of a new method for applying flexible pavement designs which can be used for EDCF-funded projects in Asia. METHODS : The method has been produced by adjusting some input data of the "AASHTO Interim Guide for Design of Pavement Structures" in accordance with certain Asian countries' geometrical features, tropical and subtropical weather, and strength of pavement materials. The Philippine regional factors, having five different grades, have been selected after taking into consideration the amount of rainfall, strength of pavement materials, and characteristics of the Asia and Pacific regions. Structural layer coefficients have been prepared for two different regions according to the geometric difference between Southeast and Southwest Asia. The Philippine and Sri Lankan coefficients have been used for Southeast Asia and Southwest Asia, respectively. CONCLUSIONS : Owing to applying this new method, it was verified that the thickness of the pavement was underestimated by between 11 cm and 16 cm compared with the originally designed thickness. Having discovered that the use of the Korean and Americanoriented factors and coefficients is not appropriate for other Asian countries, the new method is expected to enhance the quality of pavement in future projects.

This study aimed to identify the effects of modified low-dye taping and foot intrinsic muscle strengthening exercise on foot pressure in people with flat feet. The subjects were 12 participants with flat feet in their 20s. They were randomly divided into two groups: taping and strengthening exercise. They performed the interventions twice a week for six weeks. The taping group was applied the modified low-dye taping. The exercise group was performed foot intrinsic muscle strengthening exercise for 30 minutes. The data were measured by Foot Pressure Measurement. There was no significant difference in plantar pressure between taping group and exercise group. There was also no significant difference in all variables before and after intervention in all groups. The present study suggests that taping and exercise can change the foot pressure in patients with flat-footed.

The purpose of this paper is to investigate the usefulness of Flexible Logistics Strategy for coping with the difficulties that logistics industry encountered in the highly competitive market. We define a logistics network model that reflects the current logistics environment of the metropolitan area and suggest the Flexible Logistics Strategy. We investigate the efficiency of the logistics system by comparing the Flexible Vehicle Strategy with other logistics strategies at the various scenarios that can mirror the real world.

에너지 저장 매체는 소형화, 고효율화 및 그린에너지 정책에 부합하면서 연구개발이 진행되고 있으며 유연성과 신축성을 갖는 디스플레이나 웨어러블 전자기기의 발전에 상응하는 에너지 저장 매체 의 개발이 시급한 상황으로 이를 실현 할 수 있는 물질가운데, 탄소나노 재료중의 하나인 그래핀과 그 래핀 하이브리드와 같은 뛰어난 전기화학적 특성을 지니고 있는 나노 재료가 각광을 받고 있다. 또한 슈퍼커패시터와 배터리 및 연료전지 등과 같은 에너지 저장 소자에 응용하기 위한 연구가 활발하게 진 행 중에 있으며, 여러 가지 에너지 저장 매체 중 단시간에 고출력을 구현하고 장시간 신뢰성을 갖추며, 빠른 충·방전 순환특성을 가지는 슈퍼커패시터는 차세대 에너지원으로 많은 관심을 받고 있다. 본 연구에서는 플렉시블한 특성을 갖는 그래핀과 전도성 고분자 하이브리드 전극을 기반으로 하는 슈퍼커패시터를 개발하고자 하였으며 환원된 그래핀 옥사이드/폴리피롤 복합재료를 이용하여, 전기화학 적 특성을 최대화 하였다. 그 결과 굽힘 시험 전 전극의 초기 용량값은 198.5 F g-1 이었으며, 500번의 굽힘 시험 후 128.3 F g-1로 감소하는 것을 확인하였으나, 전극의 초기 전기 용량 값의 65 %의 성능을 유지하였다.

In the present work, graphene powder was synthesized by laser scribing method. The resultant flexible light-scribed graphene is very appropriate for use in micro-supercapacitors. The effect of the laser scribing process in reducing graphene oxide (GO) was investigated. GO was synthesized using a chemical mixture of GO solution; then, it was coated onto a LightScribe DVD disk and laser scribed to reduce GO and create laser-scribed graphene (LSG). The CV curves of pristine rGO at various scan rates showed that the ultimate product possesses the ability to store energy at the supercapacitor level. Charge-discharge curves of pristine rGO at two different current densities indicated that the specific capacitance (Cm) increases due to the reduction of the discharge current density. Finally, the long-term charge-discharge stability of the LSG was plotted and indicates that the specific capacitance decreases very slightly from its primary capacitance of ~10F cm−3 and that the cyclic stability is favorable over 1000 cycles.

Due to dramatic changes in the trend of corporate management (economic, labor, government), companies are being asked to adapt creative and innovative organizational culture in order to keep sustainability. Under the circumstances, flexible working hour becomes one of very effective method for org culture improvement. Recently, M company has introduced the new policy of working hours that employees can choose a couple of different time options depending on their personal situations. And it turns out to be very effective(work & life balance, increasing organizational vitality, improving efficiency of business and productivity, Recruitment of core human resources, Prevention of deviation); both team and personal performance levels has significantly improved. Therefore, it is highly recommended to adapt flexible working policies for companies seeking for a long term, sustainable corporate vision.

In this study, we report a general method for preparation of a one-dimensional (1D) arrangement of Au nanoparticles on single-walled carbon nanotubes (SWNTs) using biologically programmed peptides as structure-guiding 1D templates. The peptides were designed by the combination of glutamic acid (E), glycine (G), and phenylalanine (F) amino acids; peptides efficiently debundled and exfoliated the SWNTs for stability of the dispersion and guided the growth of the array of Au nanoparticles in a controllable manner. Moreover, we demonstrated the superior ability of 1D nanohybrids as flexible, transparent, and conducting materials. The highly stable dispersion of 1D nanohybrids in aqueous solution enabled the fabrication of flexible, transparent, and conductive nanohybrid films using vacuum filtration, resulting in good optical and electrical properties.

Graphene has shown exceptional properties for high performance devices due to its high carrier mobility. Of particular interest is the potential use of graphene nanoribbons as field-effect transistors. Herein, we introduce a facile approach to the fabrication of graphene nanoribbon (GNR) arrays with ~200 nm width using nanoimprint lithography (NIL), which is a simple and robust method for patterning with high fidelity over a large area. To realize a 2D material-based device, we integrated the graphene nanoribbon arrays in field effect transistors (GNR-FETs) using conventional lithography and metallization on highly-doped Si/SiO2 substrate. Consequently, we observed an enhancement of the performance of the GNRtransistors compared to that of the micro-ribbon graphene transistors. Besides this, using a transfer printing process on a flexible polymeric substrate, we demonstrated graphene-silicon junction structures that use CVD grown graphene as flexible electrodes for Si based transistors.