Korea Institute of Science & Technology Evaluation and Planning

A numerical study has been carried out to understand the influences of barrier arrangements on the discharge characteristics of dielectric barrier discharge (DBD). A 1.5-dimensional (1.5-D) modeling is considered in the arrangements of bare, single-barrier, and double-barrier electrodes while a two-dimensional (2-D) approach is employed in a configuration of ferroelectric packed discharge (FPD). Numerical simulations show that the evolution of microdischarges in DBD occurs sequentially in the three distinctive phases of avalanche, streamer, and decay, and that the dielectric barriers make streamer discharges stabilized and sustained in lowered electric fields without transition to spark compared with no barrier case. Especially, the highly nonuniform strong electric field effect created by the pellets appears to be formed in FPD, which enables the flue gas cleaning to be expected to enhance the decomposition efficiency.

The peer to peer (P2P) electricity trading without the need for utilities is expected to increase as the awareness of the shared economy has grown and the microgrid has spread. Furthermore, the development of renewable energy technology and the Internet technology will accelerate the dissemination of the new system. In this light, this study compares the major P2P electricity trading cases being promoted and reviews the potential development and future challenges. Since there have been little case studies of P2P electricity trading published, this study could be used as valuable information for government and corporations that are promoting or pursuing P2P electricity trading business.

Chemical vapor deposition (CVD) is a process that a solid is formed on a substrate by the chemical reaction in the vapor phase. Employing this technology, a wide range of materials, including ceramic nanocomposite coatings, dielectrics, and single crystalline silicon materials, can be coated on a variety of substrates. Among the factors influencing the design of a CVD system are the dimensions or geometry of the substrate, substrate temperature, chemical composition of the substrate, type of the deposition process, the temperature within the chamber, purity of the target material, and the economics of the production. Three major phenomena of surface reaction (kinetic), diffusion or mass transfer reaction, and desorption reaction are involved during the CVD process. Thermodynamically, CVD technology requires high temperatures and low pressures in most systems. Under such conditions, the Gibbs free energy of the chemical system quickly reaches its lowest value, resulting in the production of solids. The kinetic control of the CVD technology should always be used at low temperatures, and the diffusion control should be done at high temperatures. The coating in the CVD technology is deposited in the temperature range of 900–1400 °C. Overall, it is shown here that by controlling the temperature of the chamber and the purity of the precursors, together with the control of the flow rate of the precursors into the chamber, it is possible to partially control the deposition rate and the microstructure of the ceramic coatings during the CVD process.

Digital twin has recently received considerable attention in various industry domains. The digital twin replicates physical objects (e.g., people, objects, spaces, systems, and processes) in the real world into digital objects in the digital world. It also provides various simulations to solve problems in the real world or to improve situational operations. Therefore, the digital twin is a convergence of various technologies, such as advanced machine-learning algorithms, data analytics, super-resolution visualization and modeling, and simulation. Because the digital twin is a complicated technology, a step-by-step implementation that includes many technology elements should be considered to create a digital twin model. In this study, implementation layers are introduced to guide practical implementations of the digital twin. In addition, technology elements were suggested for the presented implementation layers. Because the suggested technology elements include clear technology definitions, various application domains (e.g., energy, transportation, logistics, environment, manufacturing, and smart cities) can easily utilize the introduced implementation layers and technology elements according to the intended purpose. Furthermore, this paper describes the evolution of digital twins. Digital twin technology has evolved continuously since 2002, when the digital twin concept was first introduced. In the described evolution levels, we show the future aspects of digital twin technology, according to the technological evolution direction. Therefore, the digital twin model can be efficiently created by considering the evolution direction and future aspects by using the suggested digital twin evolution levels.

OBJECTIVE: To evaluate wrinkle improvement and safety of a novel cosmetic dissolving microneedle patches loaded with two active compounds with different hydrophilicities, namely ascorbic acid and retinyl retinoate. METHODS: Clinical studies were performed on 24 Korean women for 12 weeks. Patients in group A were treated with retinyl retinoate-loaded dissolving microneedle patches on the left eye crow's feet area, and patients in group B were treated with ascorbic acidloaded patches on the right eye crow's feet area twice daily. Wrinkle improvement was evaluated by skin Visiometer SV 600. RESULTS: Both the retinyl retinoate- and ascorbic acid-loaded dissolving microneedle patches demonstrated statistically significant differences in all Visiometer R-values (P < 0.05). In particular, highly significant differences were shown at R1 (skin roughness) and R5 (arithmetic average roughness) (P < 0.001). Also, there were no side effects such as allergies or irritant contact dermatitis. CONCLUSION: Retinyl retinoate and ascorbic acid were successfully loaded into dissolving microneedles and used to produce novel cosmetic patches. These novel patches can be used efficiently in cosmetics given their patient usability, safety and effectiveness in wrinkle improvement.

The charge-discharge process of the room-temperature Na/S battery is studied using the Na/S cell with tetraethylene glycol dimethyl ether (TEGDME) and the solid electrolyte. The solid electrolyte is a barrier for chemical mass transport between the anode and the cathode. The sodium polysulfides as reaction products in TEGDME could therefore be investigated without interference from the anode side. During discharge, the color of the TEGDME electrolyte changes from transparent to brown, yellowish-green, and then back to transparent, and in the reverse order during charge. The first three colors are well-matched with those of prepared TEGDME solutions of Na2Sn (6 ≤ n ≤ 8), Na2S4 and Na2S, respectively. The solubility of sodium polysulfides (Na2Sn, 1 ≤ n ≤ 8) in TEGDME are measured systematically. The dissolution of sodium polysulfides is found to depend on the molar concentration of sulfur. The optimized Na/S cell using activated carbon delivers a high capacity of 1070 mAh g−1 at the first discharge, and remains at 782 mAh g−1 after 37 cycles. It also shows good rate capability with a discharge capacity of 569 mAh g−1 at 1/2 C. The coulombic efficiency is nearly 100% after the 5th cycle.

To address environmental regulations on greenhouse gas emissions and depletion of fossil fuels, many countries around the world are actively promoting electric vehicles. The penetration rate of electric vehicles, however, is different in each country. What are the causal conditions of EVs adoption? To answer the question, the fuzzy-set qualitative comparative analysis methodology, fsQCA, is employed to compare the factors affecting the deployment of electric vehicles and to draw policy implications for promoting the deployment of electric vehicles. In conclusion, some effective policies, such as tax exemption, purchase subsidies, are summarized. And it can be seen that there is no single effective policy tool or the circumstances of the countries for electric vehicle supply. Therefore, in order to promote the diffusion of electric vehicles, it is necessary to promote an effective policy mix considering the circumstances of the countries concerned.

BACKGROUND: Accreditation reviews of medical schools typically occur at fixed intervals and result in a summative judgment about compliance with predefined process and outcome standards. However, reviews that only occur periodically may not be optimal for ensuring prompt identification of and remediation of problem areas. AIMS: To identify the factors that affect the ability to implement a continuous quality improvement (CQI) process for the interval review of accreditation standards. METHODS: Case examples from the United States, Canada, the Republic of Korea and Taiwan, were collected and analyzed to determine the strengths and challenges of the CQI processes implemented by a national association of medical schools and several medical school accrediting bodies. The CQI process at a single medical school also was reviewed. RESULTS: A functional CQI process should be focused directly on accreditation standards so as to result in the improvement of educational quality and outcomes, be feasible to implement, avoid duplication of effort and have both commitment and resource support from the sponsoring entity and the individual medical schools. CONCLUSIONS: CQI can enhance educational program quality and outcomes, if the process is designed to collect relevant information and the results are used for program improvement.

The characteristics of the smart city industry and its effects on the national economy of Korea are investigated using input-output analysis. The definition and industrial classification of a smart city are established using the Delphi technique for experts in various fields, from information and communication technologies (ICT) to governmental policies for urban matters. The results of the analysis, including the production, value added and employment induction effects, show that the smart city industry has intermediate characteristics between ICT and urban construction industries, indicating that acquisition of the competitive edge of both the ICT and construction industries is the key to the success of the smart city industry. The crucial industries related to the smart city industry are identified based on an analysis of the forward and backward linkage effects, the results of which suggest the importance of the relevant service industries. The economic effects on the national economy induced by the governmental program for smart city demonstration are estimated using input-output analysis results. Overall, the results of this study indicate that facilitation of the smart city industry plays a key role not only in the sustainable city, but also in the growth of the national economy.

Abstract The main purpose of this study was to identify the effects of two major components (ie, video and group discussion) of problem‐based video instruction (PBVI) on college students’ learning. To achieve this purpose, this study examined whether or not PBVI can improve learner satisfaction, comprehension and retention by comparing the results from three dependent variables in PBVI with two other kinds of instruction: (1) problem‐based text instruction (PBTI) and (2) PBVI without group discussion. According to the findings, there were significant differences in learner satisfaction, comprehension, and delayed retention between PBVI and PBTI groups, whereas there were no significant differences in learners’ satisfaction, comprehension, and delayed retention between PBVI and PBVI without group discussion. This study implies that PBVI in college courses have the potential to enhance student satisfaction, comprehension and delayed retention.

The traditional engine valve train in a combustion engine is the mechanically driven camshaft system that provides one-fixed valve timing. The variable valve timing (VVT), however, is highly required to achieve the significant improvement in fuel economy and lower emission. To provide the VVT, the double solenoid type of actuators with steel-made armature have been developed in past years, but it requires electric power in the most engine operating period, the starting is difficult and the efficiency is low. In this paper, a new linear actuator using permanent magnets is proposed and the dynamic performances are analyzed by finite-element analysis. The results show that the designed colenoid system has a fast transition time between valve events suitable for the practical use in combustion engine valve system

This paper conducts country‐panel econometric analysis with a focus on the different roles of scientific and technological knowledge on economic growth and on the knowledge production functions. It finds that it is not scientific knowledge (academic articles) but technological knowledge (patents) that matters for economic growth, and that generating scientific knowledge does not automatically lead to the generation of technological knowledge. We find that technological knowledge is primarily determined by corporate research and development efforts, which used to be more lacking in L atin A merican countries, compared with E ast A sia. This finding sheds new light on the question of why L atin A merican and E ast A sian countries have shown such divergent economic performances.

Abstract Redox‐active organic electrode materials have garnered considerable interest as an emerging alternative to currently widespread inorganic‐(or metal)‐based counterparts in lithium‐ion batteries (LIBs). Practical use of these materials, however, has posed a challenge due to their electrically insulating nature, limited specific capacity, and poor electrochemical durability. Here, a new class of multiwalled‐carbon‐nanotube‐(MWCNT)‐cored, meso ‐tetrakis(4‐carboxyphenyl)porphyrinato cobalt (CoTCPP) is demonstrated as a 1D nanohybrid (denoted as CC‐nanohybrid) strategy to develop an advanced LIB anode. CoTCPP, which is one of the metalloporphyrins having multielectron redox activities, shows strong noncovalent interactions with MWCNTs due to its conjugated π‐bonds, resulting in successful formation of the CC‐nanohybrids. The structural uniqueness of the CC‐nanohybrid facilitates electron transport and electrolyte accessibility, thereby improving their redox kinetics. Inspired by the 1D structure of the CC‐nanohybrid, all‐fibrous nanomat anode sheets are fabricated through concurrent electrospraying/electrospinning processes. The resulting nanomat anode sheets, driven by their 3D bicontinuous ion/electron conduction pathways, provide fast lithiation/delithiation kinetics, eventually realizing the well‐distinguishable lithiation behavior of CoTCPP. Notably, the nanomat anode sheets exhibit exceptional electrochemical performance (≈226 mAh g sheet −1 and &gt;1500 cycles at 5 C) and mechanical flexibility that lie far beyond those achievable with conventional LIB anode technologies.

Despite large-scale financial support of the government, there is increasing criticism about the inefficiency of public R&amp;D investment that fails to lead directly to technological innovation of technology-based start-ups. This paper analyzes the factors that influence technological innovation in Korean technology-based start-ups based on the resource-based view (RBV). The empirical analysis combines ordinary least squares and ordered probit analysis of data collected from 248 technology-based start-ups in Korea. The analysis results statistically confirm the effects of technological capabilities and entrepreneurship on technological innovation. First, a start-up's technological capabilities measured by patents and technological competitiveness have significant positive effects on technological innovation, while the effect of having an in-house R&amp;D department for technological innovation is not significant. Second, entrepreneurship has a significant positive effect on the technological innovation of a start-up, and this positive effect has a moderating effect that further promotes the positive effect of technological competitiveness on technological innovation.

Streamer characteristics have been experimentally and numerically analyzed for pulsed-corona discharge (PCD) and dielectric-barrier discharge (DBD) to find out how the discharge methods determine them and how they, in turn, affect the generation of radicals in flue gases. Experiments have been performed and compared for decomposition of a nitrogen oxide (NO) using PCD and DBD, and the electric field and average electron energy in the streamer are measured in each discharge by using the line ratio of N/sub 2//sup +/ to N/sub 2//sup */. The measured results of electron energy reasonably explain in terms of "G-value" how the measured NO removal efficiencies have come out. The PCD having high electron energy turns out to be more efficient for generating N radicals, whereas the DBD containing relatively low electron energy is more effective for producing O radicals. Three-dimensional (3-D) and one-dimensional (1-D) numerical simulations have been carried out to understand the observed streamer dynamics in both the PCD and DBD reactors. The 3-D numerical simulation has successfully illustrated the images of streamer front propagation in a wire-cylinder PCD reactor. In the 1-D simulation for the DBD, the recurrence phenomena of streamers have numerically appeared during the rising phase of an AC voltage. Furthermore, these numerical models have properly predicted the electric fields that are comparable with the corresponding average electron energies estimated from the emission spectral measurements for the PCD and DBD.

In general, NiTi shape memory alloys are used for applications in civil structures. NiTi SMAs show good superelasticity and shape memory effect properties. However, for application of the shape memory effect, it is desirable for SMAs to show a wide temperature hysteresis, especially for civil structures which are exposed to severe environmental conditions. NiTiNb SMAs, in general, show a wider temperature hysteresis than NiTi SMAs and are more applicable for civil structures. This study examines the temperature hysteresis of NiTiNb and NiTi SMAs, and their recovery and residual stress are investigated. In addition, the tensile behaviors of SMA wires under residual stress are evaluated. This study explains the possible applications for concrete structures with the shape memory effect and illustrates two experimental results of concrete cylinders and reinforced concrete columns. For both tests, SMA wires of NiTiNb and NiTi are used to confine concrete using residual stress. The SMA wire jackets on the concrete cylinders increase the peak strength and the ductility compared to the plain concrete cylinders. In addition, the SMA wire jackets on reinforced concrete columns increase the ductility greatly without flexural strength degradation.

The goal of this paper is to deliver a concise form of discussion on the use of cost‐benefit analysis (CBA) in environmental policy formulation in the scholarships. There have been several critiques from environmental/legal economists and even from economists who are in favor of the use of CBA. The critiques of CBA can be reduced to one statement: ‘numbers don't tell us everything’. The implication from the critiques of CBA is that these evoke cautiousness or wariness against an economized calculation of CBA in the environment policy. CBA can be a valuable tool when it is carefully restricted from being used in policies such as environment, health, and natural resource policy in which inherent incommensurability exists. Copyright © 2015 John Wiley &amp; Sons, Ltd.

Background: Evaluation is not widespread in Africa, particularly evaluations instigated by governments rather than donors. However since 2007 an important policy experiment is emerging in South Africa, Benin and Uganda, which have all implemented national evaluation systems. These three countries, along with the Centre for Learning on Evaluation and Results (CLEAR) Anglophone Africa and the African Development Bank, are partners in a pioneering African partnership called Twende Mbele, funded by the United Kingdom’s Department for International Development (DFID) and Hewlett Foundation, aiming to jointly strengthen monitoring and evaluation (M&amp;E) systems and work with other countries to develop M&amp;E capacity and share experiences.Objectives: This article documents the experience of these three countries and summarises the progress made in deepening and widening their national evaluation systems and some of the cross-cutting lessons emerging at an early stage of the Twende Mbele partnership.Method: The article draws from reports from each of the countries, as well as work undertaken for the evaluation of the South African national evaluation system.Results and conclusions: Initial lessons include the importance of a central unit to drive the evaluation system, developing a national evaluation policy, prioritising evaluations through an evaluation agenda or plan and taking evaluation to subnational levels. The countries are exploring the role of non-state actors, and there are increasing moves to involve Parliament. Key challenges include difficulty of getting a learning approach in government, capacity issues and ensuring follow-up. These lessons are being used to support other countries seeking to establish national evaluation systems, such as Ghana, Kenya and Niger.

Abstract. A box model incorporating a state-of-the-art chemical mechanism for atmospheric mercury (Hg) cycling was developed to investigate the oxidation of gaseous elemental mercury (GEM) at three locations in the northeastern United States: Appledore Island (AI; marine), Thompson Farm (TF; coastal, rural), and Pack Monadnock (PM; inland, rural, elevated). The chemical mechanism in this box model included the most up-to-date Hg and halogen chemistry. As a result, the box model was able to simulate reasonably the observed diurnal cycles of gaseous oxidized mercury (GOM) and chemical speciation bearing distinct differences between the three sites. In agreement with observations, simulated GOM diurnal cycles at AI and TF showed significant daytime peaks in the afternoon and nighttime minimums compared to flat GOM diurnal cycles at PM. Moreover, significant differences in the magnitude of GOM diurnal amplitude (AI &gt; TF &gt; PM) were captured in modeled results. At the coastal and inland sites, GEM oxidation was predominated by O3 and OH, contributing 80–99 % of total GOM production during daytime. H2O2-initiated GEM oxidation was significant (∼ 33 % of the total GOM) at the inland site during nighttime. In the marine boundary layer (MBL) atmosphere, Br and BrO became dominant GEM oxidants, with mixing ratios reaching 0.1 and 1 pptv, respectively, and contributing ∼ 70 % of the total GOM production during midday, while O3 dominated GEM oxidation (50–90 % of GOM production) over the remaining day when Br and BrO mixing ratios were diminished. The majority of HgBr produced from GEM+Br was oxidized by NO2 and HO2 to form brominated GOM species. Relative humidity and products of the CH3O2+BrO reaction possibly significantly affected the mixing ratios of Br or BrO radicals and subsequently GOM formation. Gas–particle partitioning could potentially be important in the production of GOM as well as Br and BrO at the marine site.

SCOPE: Indole-3-carbinol (I3C), a derivative abundant in cruciferous vegetables such as cabbage, is well known for its various health benefits such as chemo-preventive and anti-obesity effects. I3C is easily metabolized to 3,3'-diindolylmethane (DIM), a more stable form, in acidic conditions of the stomach. However, the anti-obesity effect of DIM has not been investigated clearly. We sought to investigate the effect of DIM on diet-induced obesity and to elucidate its underlying mechanisms. METHODS AND RESULTS: High-fat diet (HFD)-fed obese mouse and MDI-induced 3T3-L1 adipogenesis models were used to study the effect of DIM. We observed that the administration of DIM (50 mg/kg BW) significantly suppressed HFD-induced obesity, associated with a decrease in adipose tissue. Additionally, we observed that DIM treatment (40 and 60 μM), but not I3C treatment, significantly inhibited MDI-induced adipogenesis by reducing the levels of several adipogenic proteins such as PPAR-γ and C/EBPα. DIM, but not I3C, suppressed cell cycle progression in the G1 phase, which occurred in the early stage of adipogenesis, inducing post-translational degradation of cyclin D1 by inhibiting ubiquitin specific peptidase 2 (USP2) activities. CONCLUSION: Our findings indicate that cruciferous vegetables, which can produce DIM as a metabolite, have the potential to prevent or treat chronic obesity.