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Organic–inorganic metal halide perovskites have gained considerable attention for next-generation photovoltaic cells due to rapid improvement in power conversion efficiencies. However, fundamental understanding of underlying mechanisms related to light- and bias-induced effects at the nanoscale is still required. Here, structural variations of the perovskites induced by light and bias are systematically investigated using scanning probe microscopy techniques. We show that periodically striped ferroelastic domains, spacing between 40 to 350 nm, exist within grains and can be modulated significantly under illumination as well as by electric bias. Williamson-Hall analysis of X-ray diffraction results shows that strain disorder is induced by these applied external stimuli. We show evidence that the structural emergence of domains can provide transfer pathways for holes to a hole transport layer with positive bias. Our findings point to potential origins of I–V hysteresis in halide perovskite solar cells., Organic–inorganic metal halide perovskite solar cells have been under the spotlight but what happens in the working solar cell device at the nanoscale remains elusive. Here Kim et al. show that light and voltage bias can induce strain and structural variation which may cause J–V scan hysteresis.

Summary Fluorine-doped tin oxide glass substrate is typically used for state-of-the-art perovskite solar cells (PSCs). However, indium-doped tin oxide (ITO) is better due to higher transparency for a given conductivity, although it has lower tolerance to high-temperature processes required for the compact and mesoporous TiO2 layers. Here we overcome this challenge by developing and utilizing a new electrode design. We successfully demonstrate high-efficiency mesoscopic PSCs on annealed ITO substrates showing improved photocurrent without sacrificing fill factor. After further optimizations of cell geometry and substrate conductivity guided by simulation, a certified 19.63% efficiency is achieved on 1 cm2 for ITO-based mesoscopic PSC, which is the highest among PSCs prepared by gas quenching. This work is useful for providing design principles and methods for optimizing cell geometry, metal electrode design, and substrate conductivity requirements for large-area PSCs.

Organic-inorganic halide perovskite solar cells (PSCs) have emerged as promising candidates for next generation solar cells due to the rapid increase in their power conversion efficiency. The instability of these cells under illumination, however, remains a major technical barrier for commercialization. In this work, by fabricating full perovskite cells (not test structures) that is compatible with in photoluminescence (PL), for the first time we have achieved in-situ monitoring of the localized charge carrier and ion dynamics in an operating perovskite solar cell under light soaking, using nanoscale resolved in-situ PL and time-resolved PL (tr-PL) microscopy. By analyzing the dynamic PL lifetime and intensity under different light soaking conditions and its correlation with the shape of the voltage current curve, we explain the different scenarios of ion migration and accumulation at the interface and in the bulk that result in different hysteresis behaviors. Our results suggest that mobile positive ions, predominantly iodide vacancies pre-accumulate near the spiro-MeOTAD/perovskite interface of as-fabricated devices, reducing charge-carrier separation and increasing recombination at that electrode. After light soaking for a short time at open circuit, these positive ions drift away from the interface under the altered electric field, improving device performance. After prolonged light soaking, however, negative ions, predominantly iodide interstitials drift to the spiro-MeOTAD/perovskite interface, significantly enhancing carrier recombination at that electrode. In contrast, light soaking had less effect at short-circuit because the electric field is invariant at short circuit. In addition to the light-soaked-induced ion movement under short circuit is by diffusion rather than by drift. This result in ionic redistribution and ion-recombination increases PL intensity uniformity across the device and resulting in relatively stable device performance. Our work reveals that the bias voltage during light soaking results in different dynamic processes, which can be either positive or negative. Analysis on the corresponding PL images revealed a difference in charge carrier and ion dynamics between grain interior and grain boundary during light soaking. The larger density of grain boundaries causes a faster ion migration rate in the regions with smaller grains. Therefore, it may be possible to reduce J-V hysteresis by producing larger grains. Our results provide novel insight into the effect of light soaking on ions and subsequent effect on carrier dynamics for better understanding of the operation of perovskite solar cells.

Monolithic perovskite/silicon tandem solar cells show great promise for further efficiency enhancement for current silicon photovoltaic technology. In general, an interface (tunnelling or recombination) layer is usually required for electrical contact between the top and the bottom cells, which incurs higher fabrication costs and parasitic absorption. Most of the monolithic perovskite/Si tandem cells demonstrated use a hetero-junction silicon (Si) solar cell as the bottom cell, on small areas only. This work is the first to successfully integrate a low temperature processed (≤150 °C) planar CH3NH3PbI3 perovskite solar cell on a homo-junction silicon solar cell to achieve a monolithic tandem without the use of an additional interface layer on large areas (4 and 16 cm2). Solution processed SnO2 has been effective in providing dual functions in the monolithic tandem, serving as an ETL for the perovskite cell and as a recombination contact with the n-type silicon homo-junction solar cell that has a boron doped p-type (p++) front emitter. The SnO2/p++ Si interface is characterised in this work and the dominant transport mechanism is simulated using Sentaurus technology computer-aided design (TCAD) modelling. The champion device on 4 cm2 achieves a power conversion efficiency (PCE) of 21.0% under reverse-scanning with a VOC of 1.68 V, a JSC of 16.1 mA cm−2 and a high FF of 78% yielding a steady-state efficiency of 20.5%. As our monolithic tandem device does not rely on the SnO2 for lateral conduction, which is managed by the p++ emitter, up scaling to large areas becomes relatively straightforward. On a large area of 16 cm2, a reverse scan PCE of 17.6% and a steady-state PCE of 17.1% are achieved. To our knowledge, these are the most efficient perovskite/homo-junction-silicon tandem solar cells that are larger than 1 cm2. Most importantly, our results demonstrate for the first time that monolithic perovskite/silicon tandem solar cells can be achieved with excellent performance without the need for an additional interface layer. This work is relevant to the commercialisation of efficient large-area perovskite/homo-junction silicon tandem solar cells.

Cesium (Cs) metal halide perovskites for photovoltaics have gained research interest due to their better thermal stability compared to their organic–inorganic counterparts. However, demonstration of highly efficient Cs-based perovskite solar cells requires high annealing temperature, which limits their use in multijunction devices. In this work, low-temperature-processed cesium lead (Pb) halide perovskite solar cells are demonstrated. We have also successfully incorporated the less toxic strontium (Sr) at a low concentration that partially substitutes Pb in CsPb1–xSrxI2Br. The crystallinity, morphology, absorption, photoluminescence, and elemental composition of this low-temperature-processed CsPb1–xSrxI2Br are studied. It is found that the surface of the perovskite film is enriched with Sr, providing a passivating effect. At the optimal concentration (x = 0.02), a mesoscopic perovskite solar cell using CsPb0.98Sr0.02I2Br achieves a stabilized efficiency at 10.8%. This work shows the potential of inorgani...

Perovskite materials have generated significant interest from academia and industry as a potential component in next-generation, high-efficiency, low-cost, photovoltaic (PV) devices. The record efficiency reported for perovskite solar cells has risen rapidly, and is now more than 22%. However, due to their complex dynamic behaviour, the process of measuring the efficiency of perovskite solar cells appears to be much more complicated than for other technologies. It has long been acknowledged that this is likely to greatly reduce the reliability of reported efficiency measurements, but the quantitative extent to which this occurs has not been determined. To investigate this, we conduct the first major inter-comparison of this PV technology. The participants included two labs accredited for PV performance measurement (CSIRO and NREL) and eight PV research laboratories. We find that the inter-laboratory measurement variability can be almost ten times larger for a slowly responding perovskite cell than for a control silicon cell. We show that for such a cell, the choice of measurement method, far more so than measurement hardware, is the single-greatest cause for this undesirably large variability. We provide recommendations for identifying the most appropriate method for a given cell, depending on its stabilisation and degradation behaviour. The results of this study suggest that identifying a consensus technique for accurate and meaningful efficiency measurements of perovskite solar cells will lead to an immediate improvement in reliability. This, in turn, should assist device researchers to correctly evaluate promising new materials and fabrication methods, and further boost the development of this technology.

The hot-phonon bottleneck effect in lead-halide perovskites (APbX3) prolongs the cooling period of hot charge carriers, an effect that could be used in the next-generation photovoltaics devices. Using ultrafast optical characterization and first-principle calculations, four kinds of lead-halide perovskites (A=FA+/MA+/Cs+, X=I−/Br−) are compared in this study to reveal the carrier-phonon dynamics within. Here we show a stronger phonon bottleneck effect in hybrid perovskites than in their inorganic counterparts. Compared with the caesium-based system, a 10 times slower carrier-phonon relaxation rate is observed in FAPbI3. The up-conversion of low-energy phonons is proposed to be responsible for the bottleneck effect. The presence of organic cations introduces overlapping phonon branches and facilitates the up-transition of low-energy modes. The blocking of phonon propagation associated with an ultralow thermal conductivity of the material also increases the overall up-conversion efficiency. This result also suggests a new and general method for achieving long-lived hot carriers in materials., Slow cooling of hot charge carriers in lead halide perovskite could be used in photovoltaics devices. Here, Yang et al. study hot carrier dynamics by transient absorption spectroscopy. They relate the phonon bottleneck to the up-conversion of low-energy phonons, facilitated by the presence of organic cations.

With advance of cloud computing technologies, there have been more diverse and heterogeneous workloads running on cloud datacenters. As more and more workloads run on the datacenters, the contention for the limited shared resources may increase, which can make the management of the resources difficult, often leading to low resource utilization. For effective resource management, the management software for the datacenters should be redesigned and used in a software-defined way to dynamically allocate "right" resources to workloads based on different characteristics of workloads so that they can decrease the cost of their operation while meeting the service level objectives such as satisfying the latency requirement. However, recent datacenter resource management frameworks do not operate in such software-defined ways, thus leading to not only the waste of resources, but also the performance degradation. To address this problem, we have designed and developed a workload-aware resource management framework for software-defined compute. The framework consists mainly of the workload profiler and workload-aware schedulers. To demonstrate the effectiveness of the framework, we have prototyped the schedulers that minimize the interferences on the shared computing and memory resources. We have compared them with the existing schedulers in the OpenStack and VMWare vSphere testbeds, and evaluated its effectiveness in high contention scenarios. Our experimental study suggests that the use of our proposed approach can lead to up to 100 % improvements in throughput and up to 95 % reductions in tail latency for latency critical workloads compared to the existing ones.

Summary Development of efficient solar cells under indoor light has attracted tremendous attention because of the Internet of Things revolution. Here we investigate the effect of chlorine in perovskite precursors for indoor light applications. Use of chlorine has an effect on the photovoltaic performance of perovskite solar cells, especially under low-intensity indoor light. Based on the characterization of leakage current, crystalline structure, and Urbach tail, we reveal that chlorine doping of the perovskite layer influences the movement of photo-generated carriers and ions because of the smaller bulk defects in perovskite. In particular, we suggest that chlorine doping in perovskite facilitates hole extraction on its top surface and contributes to suppression of ion migration and non-radiative recombination, as confirmed by Kelvin probe force microscopy measurements. We demonstrate high performance of perovskite solar cells with a maximum power density of 35.25 (231.78) μW/cm2 under 400 lux light-emitting diode (halogen) illumination.

UV induced degradation is a big issue for perovskite-based solar cells. Parasitic ultraviolet (UV) absorption by the “sun-facing” carrier transport layer in a perovskite cell also hinders the electrical performance when the cell is a top cell for a Si-based tandem. In this work, we tackle these issues by applying textured polydimethylsiloxane (PDMS) films that incorporate a down-shifting material (Ba,Sr)2SiO4:Eu2+ micron phosphor on the front of monolithic perovskite/silicon tandem cells. This film serves multiple purposes optically: antireflective control for the top cell, light trapping in the Si cell as well as absorbing UV and re-emitting green light with high quantum yield. The morphology of the phosphor, optical properties of the phosphor as well as the phosphor incorporated film, water, moisture, UV stability as well as the mechanical flexibility of the anti-reflective down-shifting film were investigated. The effect of phosphor concentration in the antireflective PDMS film on tandem device efficiencies was also studied. This down-shifting antireflective film is suitable for large areas. When applied onto a 4 cm2 monolithic perovskite/silicon tandem solar cell, the power conversion efficiency was improved from 20.1% (baseline device without any anti-reflective film) to 22.3% (device with anti-reflective film but without the phosphors) and to 23.1% (device with down-shifting and antireflective film). The steady-state efficiency of 23.0% and a high FF of 81% achieved by the champion device are the highest values to date for a monolithic perovskite/Si tandem that uses homo-junction-silicon bottom cell. Moreover, results of continuous UV irradiation test show that this composite down-shifting antireflection film significantly enhances the UV stability for the tandem device. The demonstrated efficiency and stability enhancement achieved by such elegant approach paves a way for improving the commercial viability of perovskite/silicon tandems and other perovskite photovoltaic applications.

Many significant research achievements in the past few decades have demonstrated that convolutional neural networks (CNNs) could be capable of steering wheel control which is the basic and essential maneuver of autonomous vehicles. We propose an end-to-end steering controller with CNN-based closed-loop feedback for autonomous vehicles that improves driving performance compared to traditional CNN-based approaches. This paper demonstrates that the proposed neural network, DAVE-2SKY, is able to learn to inference steering wheel angles for the lateral control of self-driving vehicles through initial supervised pre-training and subsequent reinforced closed-loop post-training with images from a camera mounted on the vehicle. We used the PreScan simulator and Caffe deep learning framework for training under diversified circumstances in a software in the loop (SIL) simulation environment. We used DRIVE TM PX2 computer to implement a self-driving car for an experimental validation of the proposed end-to-end controller. The performance of the proposed system has been investigated under simulations and on-road tests as well. This work shows that the CNN-based end-to-end controller performs robust steering control even under partially observable road conditions, which indicates the possibility of fully self-driving vehicles controlled by CNN-based end-to-end steering controllers.

One of the most important factors in training object recognition networks using convolutional neural networks (CNNs) is the provision of annotated data accompanying human judgment. Particularly, in object detection or semantic segmentation, the annotation process requires considerable human effort. In this paper, we propose a semi-supervised learning (SSL)-based training methodology for object detection, which makes use of automatic labeling of un-annotated data by applying a network previously trained from an annotated dataset. Because an inferred label by the trained network is dependent on the learned parameters, it is often meaningless for re-training the network. To transfer a valuable inferred label to the unlabeled data, we propose a re-alignment method based on co-occurrence matrix analysis that takes into account one-hot-vector encoding of the estimated label and the correlation between the objects in the image. We used an MS-COCO detection dataset to verify the performance of the proposed SSL method and deformable neural networks (D-ConvNets) as an object detector for basic training. The performance of the existing state-of-the-art detectors (DConvNets, YOLO v2, and single shot multi-box detector (SSD)) can be improved by the proposed SSL method without using the additional model parameter or modifying the network architecture., Submitted to International Conference on Image Processing (ICIP) 2018

In this work, we report on the design principles of high-power perovskite solar cells (PSCs) for low-intensity indoor light applications, with a particular focus on the electron transport layers (ETLs). It was found that the mechanism of power generation of PSCs under low-intensity LED and halogen lights is surprisingly different compared to the 1 Sun standard test condition (STC). Although a higher power conversion efficiency (PCE) was obtained from the PSC based on mesoporous-TiO2 (m-TiO2) under STC, compared to the compact-TiO2 (c-TiO2) PSC, c-TiO2 PSCs generated higher power than m-TiO2 PSCs under low-intensity (200–1600 Lux) conditions. This result indicates that high PCE at STC cannot guarantee a reliable high-power output of PSCs under low-intensity conditions. Based on the systemic characterization of the ideality factor, charge recombination, trap density, and charge-separation, it was revealed that interfacial charge traps or defects at the electron transport layer/perovskite have a critical impact on the resulting power density of PSC under weak light conditions. Based on Suns-VOC measurements with local ideality factor analyses, it was proved that the trap states cause non-ideal behavior of PSCs under low-intensity light conditions. This is due to the additional trap states that are present at the m-TiO2/perovskite interface, as confirmed by trap-density measurements. Based on Kelvin probe force microscopy (KPFM) measurements, it was confirmed that these traps prohibit efficient charge separation at the perovskite grain boundaries when the light intensity is weak. According to these observations, it is suggested that for the fabrication of high-power PSCs under low-intensity indoor light, the interface trap density should be lower than the excess carrier density to fill the traps at the perovskite's grain boundaries. Finally, using the suggested principle, we succeeded in demonstrating high-performance PSCs by employing an organic ETL, yielding maximum power densities up to 12.36 (56.43), 28.03 (100.97), 63.79 (187.67), and 147.74 (376.85) μW/cm2 under 200, 400, 800, and 1600 Lux LED (halogen) illumination which are among the highest values for indoor low-intensity-light solar cells.

Herein, we report the dual functionality of a single n-type gallium nitride (n-GaN) layer as an electron transporter and transparent conductor, which has applications in reusable organic solar cells. After silicon doping with an optimized electron concentration, thin-film layer of GaN showed exceptional electrical properties including charge carrier mobility of 161 cm2 V−1s−1, electrical conductivity of 1.4ⅹ106 S cm−1, and sheet resistance of 11.1 Ω cm−2. Organic solar cells based on n-GaN exhibited power conversion efficiency comparable to those based on a conventional ITO/ZnO bilayered cathode. Furthermore, the n-GaN substrates exhibited reusability; due to excellent chemical stability of n-GaN, the reconstructed organic solar cells maintained their initial performance after the substrates were recycled. We suggest a new type of reusable n-GaN cathode layer featuring an integrated electron transporting layer and transparent electrode.

The smart grid is a developing network of transmission lines, equipment, controls and new technologies working together to respond immediately to 21st Century demand for electricity, but the smart grid may also create much new vulnerability if not deployed with the appropriate security controls. In this paper, to evaluate the secure GOOSE message performance, we implemented the IEC 62351-6 MAC mechanism, applied it on F-IED using the IEC 61850 GOOSE stack and the HSM, built the security test environment, and obtained test results.

The influence of rapid-set accelerating admixtures on the setting behavior and early-age strength of a cement matrix was investigated to evaluate the appropriateness of the specification and test methods for shotcrete set accelerators. The results verified two different rapid setting behaviors according to the types of accelerator. The aluminate-base and the calcium aluminate cement-base accelerators facilitate hydration by formation of a calcium aluminate solid solution, whereas the alkali-free set accelerating agents present rapid setting time by the formation of ettringite. It was also found that the Vicat test was more desirable than the Gillmore test as the standard for setting time evaluation. Additionally, the cement mortar mixed with the aluminate-base and the calcium aluminate cement-base accelerators exhibited very fast development of early-age compressive strength. However, most of the set accelerators, except for alkali-free accelerators, failed to satisfy the specification because of greater than 40% compressive strength loss at 28 d.

Two-dimensional simulation studies are performed for modified laser wakefield acceleration. After one laser pulse, another identical laser pulse is sent to the plasma to amplify the wake wave resonantly. The simulation results show that the number of injected electrons is bigger than that of the single pulse case and the beam energy is higher as well. In addition, increase of the transverse amplitude is noticed in the wake wave after the second laser pulse. This shows that the transverse motion of the wake wave enhances the wave breaking for strong injection and acceleration of electron beams.

Although set accelerating agents are used generally in New Austrian Tunneling Method, the standards for test methods and quality of set accelerating agents are not prescribed domestically. In this study, the proprieties of the various standards and the characteristics of set accelerating agents for shotcrete were evaluated. The alkali contents of set accelerating agents based on silicate, aluminate and cement were higher than those of alkali-free ones. From the result, it is thought that the quality control of aggregate should be enhanced and that the number of test cycle of alkali-aggregate reaction should be increased. The setting times of cement paste with set accelerating agents based on silicate and alkali-free ones were different largely with mixing methods. Compressive strength of mortar with set accelerating agents based on silicate, aluminate and cement at one day satisfied the specifications of Korea Concrete Institute. However, the strength ratio compared to control mix at 28 days showed as except for the alkali-free set accelerating agents. As a results of setting time and strength test, the establishment of domestic standards that can reflect the characteristics of materials and construction methods of tunnels and that can increase quality of set accelerating agents is required immediately.

The characteristics of pulse compression during the laser pulse amplification using two counter-propagating laser pulses have been investigated using a one-dimensional fluid model of stimulated Raman backscattering. The front and the rear pulse widths of the amplified laser pulse are examined in terms of the initial pump and seed amplitude, and the ratio of the electron plasma frequency to the laser frequency. The pulse widths have a common scaling behaviour in time over the considered parameter regime. The scaling exponents of the pulse widths during broadening and compression are all the same as 1.0. The pulse compression scaling shows a reciprocal behaviour to the peak energy growth.

WISDOM is an international initiative to deploy large-scale in-silico docking on a public grid infrastructure in an attempt to find potential drugs against neglected or emerging diseases such as Malaria and Avian Flu. Within the framework of the WISDOM initiative, large-scale deployments of in silico docking have been done on production grid infrastructures, demonstrating the relevance of large scale grids for high throughput virtual screening from scientific and grid deployment perspective. However, from the usability point of view, there still seems to be a lot to be done in order to be able to get the grid-enabled large-scale virtual screening approach handier for non-experts of grid computing. To address this issue, we have developed an intuitive and easy-to-use grid-enabled virtual screening tool called Drugscreener-G (DSG), aiming to help scientists in drug discovery including biologists and biochemists to more easily carryout large-scale deployment of molecular docking on grids without having to know details of grid middleware services and tools. With the help of DSG, scientists can easily have access to the PDB database, download and view the 3D structure of target proteins of their interest, launch and manage millions of in-silico docking simulations on the Grid. To facilitate the analysis of docking results, visualization and molecular modeling tools such as Jmol and Chimera have been integrated into DSG as well. The DSG client tool is now being used and tested by biologists in Chonnam National University, one of long-time partners of the WISDOM collaboration. With the help of tools like DSG, their long-time dream of large-scale virtual screening on their own at any time with any help from grid experts is to be made realized in the near future.

AMI is the totality of systems and networks used to measure, collect, store, analyze, and use energy usage data. The industry and technology surrounding AMI has been evolving at a very fast pace for the past several years. In this paper, we propose new key establishment and security algorithm based on public key cryptography to solve AMI network security problems. We evaluate the performance of the proposed key establishment procedure compared with existing algorithm, and we find that the performance of proposed algorithm.

TETRA (Terrestrial Trunked Radio) is the standard of DTRS(Digital Trunked Radio System) developed by the ETSI(European Telecommunications Standards Institute). Currently, TETRA has been selected as the power IT wireless backbone network in Korea while the traditional distribution automation system has used the wireless network of mobile service provider using CDMA(Code Division Multiple Access) and WCDMA(Wideband CDMA) modems. Therefore, the development of gateway platform is indispensable according to the change to the TETRA network. In this paper, we propose an embedded Linux-based gateway platform for transmitting industrial power IT protocol using TETRA network.

The next generation power IT system will consist of automated transmission and distribution systems that support efficient and reliable supply and delivery of power. The goal is to create a power IT system capable of handling emergency and disaster situations, while also able to accommodate current and future utility business environments, market requirements, and customer needs. In this paper, we propose multi-function TETRA Gateway (MFTG) that can convert various power IT protocols into TETRA protocols to show that the next generation electric power IT system can be constructed in TETRA radio infrastructure. Our MFTG is a TETRA network equipment that converts power IT protocols (for example, transformer load monitoring protocol, RTU (Remote Terminal Unit) protocol for monitoring power transmission steel tower wind direction/wind velocity, DLMS, DNP, and IEC61850 etc...) into TETRA protocols through short data, status messaging and packet data.

The characteristics of pulse compression during the laser pulse amplification using a counter-propagating pump and plasmas have been investigated using a one-dimensional fluid model of stimulated Raman backscattering. The pulse widths of the amplified laser at the front and rear half are examined in terms of the initial amplitudes of the pump and the seed, and the ratio of the electron plasma frequency to the laser frequency. The pulse widths have a common scaling behaviour in time over the considered parameter regime. The scaling exponents of the pulse widths during broadening and compression are all the same as 1.0. The pulse compression scaling shows a reciprocal behaviour to the peak energy growth.

A new microwave imaging reflectometry (MIR) system for KSTAR is being developed based on the experience gained via the TEXTOR proof-of-principle system [H. Park et al., Rev. Sci. Instrum. 74, 4239 (2003)] which aimed to measure the poloidal image of the electron density fluctuations essential for transport studies. The KSTAR system will adopt a multi-frequency probe beam source in the range of 90 ∼ 100 GHz (X-mode case), which will enable the measurement of 2-D (radial and poloidal) fluctuations of the multiple cut-off layers, simultaneously. The optical system of the MIR system will be combined with the 2nd ECEI system (identical to the first ECEI system [G.S. Yun et al., Rev. Sci. Instrum. 81, 10D930 (2010)]) on KSTAR. The design of the launching and receiving optics of the MIR system will be constrained in order to maintain the performance of the ECEI system and thus it is necessary to consider sharing the zoom lens of the ECEI system. This stringent constraint is a challenge considering the tight wavefront matching requirement to obtain proper images for a wide range of cut-off layers within the focal depth. This paper discusses the details of the MIR system design that is compatible with the 2nd ECEI system on KSTAR.