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Panax ginseng sprouts have important medicinal properties and thus the optimization of growth conditions is an important research goal. The effects of LED treatment and plasma-activated water on the growth and quality of Panax ginseng sprouts (PGS) in hydroponic cultivation were evaluated. Using 1-year-old ginseng plants, light was applied 9-18 h for the CGS, TGS1, TGS2, and TGS3 groups and 24 h for TGS4. Plasma-activated water was used in all groups except CGS and TGS1, and fermentation nutrient solutions (NO) were added to TGS1, TGS3, and TGS4. The TGS4 group had a high total length and initial length on days 7 and 14. At 21 days, the growth of TGS1, TGS3, and TGS4 with NO nutrient solutions increased. The total decay rate (%) was low (4.24-4.65%) for TGS1, TGS2, and TGS3. Although the chlorophyll a, b, and total chlorophyll contents were significantly higher in TGS4 than in other groups (p

The learning and inference efficiencies of an artificial neural network represented by a cross-point synaptic memristor array can be achieved using a selector, with high selectivity (I

Pesticides are emergent toxins often identified in aquatic environments. In the present study, microplasma was employed to reduce the pesticide content in water. The degradation efficacy, rate, and pathways of standard organophosphorus pesticides (namely, chlorpyrifos, chlorpyrifos oxone, and diazinone) and an organochlorine pesticide (namely, DDT solution) were evaluated using microplasma. High-performance liquid chromatography (HPLC) analysis was performed to elucidate the degradation efficiency of pesticides as a function of plasma-produced substances that originally contributed to the main reduction procedure. Microplasma produces several types of radicals or reactive substances, for instance dissolved ozone (O3), nitrogen oxides, hydroxyl radicals (OH radicals), and hydrogen peroxide (H2O2). The removal potential differs due to the existence or absence of varieties of plasma-produced substances. The functions of major plasma-produced species on pesticide removal were determined by a passive technique. Nitrogen oxides showed a key role in organophosphorus pesticide removal, whereas dissolved ozone and OH radicals played major roles in DDT degradation. HPLC data showed that plasma-induced pesticide removal showed first-order reaction kinetics. The pesticide removal pathways through microplasma were validated by investigating the achieved data from LC-MS and GC-MS.

This study aims to evaluate the value of time (VOT) for commuting time according to population subgroups in Seoul, Korea, by using the life satisfaction approach. We employed both linear and ordere...

The Conductive-bridge random-access memory (CBRAM) cell is a promising candidate for a terabit-level non-volatile memory due to its remarkable advantages. We present for the first time TiN as a diffusion barrier in CBRAM cells for enhancing their reliability. CuO solid-electrolyte-based CBRAM cells implemented with a 0.1-nm TiN liner demonstrated better non-volatile memory characteristics such as ~ 106 AC write/erase endurance cycles with 100-μs AC pulse width and a long retention time of ~ 7.4-years at 85 °C. In addition, the analysis of Ag diffusion in the CBRAM cell suggests that the morphology of the Ag filaments in the electrolyte can be effectively controlled by tuning the thickness of the TiN liner. These promising results pave the way for faster commercialization of terabit-level non-volatile memories.

Thiamine dilauryl sulfate (TDS) is a food additive that is used as a bactericidal agent. This study examines the antimicrobial effect of TDS on tofu inoculated with Escherichia coli O157:H7, Salmonella Typhimurium, Listeria monocytogenes, and Bacillus cereus. Tofu was inoculated with 100 μL of each microorganism and TDS solution (0.1, 0.5, 1, and 2%) was added to all bags, which were stored at 5 and 25 °C for 5 days. Sensory evaluations were conducted with tofu stored at 5 °C. At 5 °C, with a 2% TDS, E. coli O157:H7, S. Typhimurium, L. monocytogenes, and B. cereus were reduced by 0.29, 0.36, 0.70, and 1.47 log CFU/g, respectively. None of the sensory characteristics of tofu treated with TDS were significantly different from those of the control. Consequently, this study shows the potential of TDS as an antimicrobial agent with a practical application in tofu to ensure food safety.

This study investigated the microbial contamination of commercial tofu from local supermarkets in Seoul, Korea. Growth modeling of Bacillus cereus isolated from spoiled tofu was used to determine the appropriate and temperature for safe storage of tofu. During the monitoring of 100 commercial tofu products, pathogenic bacteria (B. cereus, Staphylococcus aureus, Listeria monocytogenes, Salmonella spp., and enterohemorrhagic Escherichia coli O157:H7 [EHEC]) were not detected. Aerobic bacteria were isolated from 32 of 100 tofu samples because of different sterilization and packaging methods. To isolate the dominant microorganism involved in tofu putrefaction, tofu was intentionally spoiled by storage at 30 °C for 24 h. After spoilage, the most abundant colonies were harvested and confirmed as B. cereus by analyzing their 16 S ribosomal RNA (rRNA) sequences and fatty acid compositions. To investigate growth properties on tofu, isolated B. cereus was cultured and inoculated on tofu. The growth of B. cereus at different storage temperatures (15 °C, 20 °C, 25 °C, and 30 °C) was analyzed. As a result, the appropriate storage time of tofu stored at 5 °C, 10 °C, and 15 °C was determined to be 9.99, 4.17, and 2.08 days, respectively.

This study was performed in order to examine the effect of a thermoelectric cooling system combined with plasma on beef. Beef was studied in a box with a thermoelectric cooling system and plasma generation apparatus (TCS-1), a box with thermoelectric cooling system (TCS-2) and a polystyrene box (control). A temperature inside the thermoelectric cooling system was kept below 2°C, and volatile basic nitrogen (VBN) values of TCS-1 and TCS-2 were 7.72 mg% and 9.20 mg%, respectively. The thiobarbituric acid (TBA) value (0.52 mgMA/kg) of TCS-1 was significantly lower than that (0.91 mgMA/kg) of TCS-2. For volatile basic nitrogen (VBN) value, TCS-1 maintained freshness compared to TCS-2, since the freshness of TCS-1 value (6.98-9.77 mg%) was less than that of TCS-2 (6.98-11.45 mg%) during storage. The microbial counts of TCS-1 and TCS-2 were 4.62 log CFU/g and 7.09 log CFU/g, respectively, on the 7th day, which were lower than that (8.45 log CFU/g) of control on the 3rd day. Sensory evaluation of TCS-1 showed the highest scores for appearance, color, juiciness, and overall acceptability than the others. In conclusion, TCS-1 was effective for maintaining freshness of beef during storage.

This study investigated how changes in land surface temperature (LST) during 2004 and 2014 were attributable to zoning-based land use type in Seoul in association with the building coverage ratio (BCR), floor area ratio (FAR), and a normalized difference vegetation index (NDVI). We retrieved LSTs and NDVI data from satellite images, Landsat TM 5 for 2004 and Landsat 8 TIRS for 2014 and combined them with parcel-based land use information, which contained data on BCR, FAR, and zoning-based land use type. The descriptive analysis results showed a rise in LST for the low- and medium-density residential land, whereas significant LST decreases were found in high-density residential, semi-residential, and commercial areas over the time period. Statistical results further supported these findings, yielding statistically significant negative coefficient values for all interaction variables between higher-density land use types and a year-based dummy variable. The findings appear to be related to residential densification involving the provision of more high-rise apartment complexes and government efforts to secure more parks and green spaces through urban redevelopment and renewal projects.

This study investigated the antimicrobial activity of malic acid (MA), grapefruit seed extract (GSE), and combined (MA+GSE) treatment against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on fresh-cut lettuce. The antimicrobial effects of 1% MA and 0.5% GSE alone and in combination (1% MA+0.5% GSE) were tested on artificially inoculated lettuce during storage at 5°C for 14 days. The maximum reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes were 4.96, 4.80, and 3.95 log CFU/g observed with MA+GSE during storage for 14 days, respectively. MA+GSE showed the greatest reduction against in E. coli O157:H7 and L. monocytogenes. These results indicate that the combined treatment was more effective than MA and GSE alone treatment. Therefore, it suggests that MA + GSE could be used as an effective intervention method for improving microbiological safety of fresh-cut lettuce.

For the distribution of fresh produce, the thermoelectric cooling system combined with thermo electric materials (TEM) and phase change material (PCM) was studied. The PCM used this study was produced by in-situ polymerization technology which referred microencapsulation of hydrocarbon (n-tetradecane and n-hexadecane). In this study, quality characteristics of bell peppers in thermoelectric cooling system combined with TEM and PCM were analyzed and control was placed in an EPS (expanded polystyrene) box. As a result of quality characteristics analysis, weight of bell peppers decreased and moisture content of bell peppers was 90.96~94.43% during storage. Vitamin C content of bell pepper decreased during storage and reduction ratio of control was higher than that of BPT-5 treatment(bell pepper in thermoelectric cooling system with PCM which is kept the temperature at 5℃). The result of color value, on 21 day, ΔE value of BPT-5 treatment was 5.05 while that of control was 41.8. On 21 day, total bacteria count of BPT-5 treated bell pepper shown less than that of control. In conclusion, it suggested that the thermoelectric cooling system combined with PCM improved quality of fresh produce during transportation and storage.

This study investigates the effects of the urban spatial structure on the excess commuting rate (ECR) by comparing commuting patterns in two cities having distinctive urban forms, Seoul, Korea and Los Angeles, California, USA. A major difference was found in that commuters working closer to employment centres, or living in single-family detached housing in LA, are likely to have lower ECR, but not in Seoul. Employment suburbanisation, strict zoning separating residence and workplace and single-family housing-dominant low-density suburbs in LA are regarded as the reasons for their lower ECRs, which, by definition, imply relatively shorter actual commute duration and/or longer minimum time. Seoul can learn a lesson from LA for employment decentralisation in order to reduce actual commute time, while land use patterns in Seoul such as high level of mixed land use and compact development can provide policy implications for LA for improving commuters’ accessibility and reducing minimum time.

Abstract Recently, the demand for more data storage and fast processing has been dramatically increased for the big data markets such as artificial intelligence (AI), virtual reality (VR), autonomous car, and internet of things (IoT). Thus, a new memory such as a storage class memory (SCM) has been introduced since it can perform a reasonable latency compared to DRAM and a lower bit-cost than NAND flash memory [1]. Remind that, generally, a SCM has been fabricated with three-dimensional cross point memory cell array [2]. As a candidate memory cell for SCM, resistive-random-access-memory (ReRAM) has been proposed; i.e., called storage-type SCM. Santini, C. A. et al. demonstrated amorphous carbon oxide (a-COx) based ReRAM-cell having a reasonable memory window margin (I on/I off > 100), a fast switching speed of 20~50 ns at ~ 100-nm-diameter memory cell size. However, it showed extremely a high forming voltage (V forming) of ~ 5.0 V and a high reset voltage (V reset) of ~ – 4.0 V [3]. In particular, the a-COx based ReRAM-cell presented a different bi-stable memory characteristic for another typical ReRAM-cells; i.e., its bias directions of set and reset were opposite to a typical ReRAM, which mechanism was not evidently proved. In addition, the forming process for this ReRAM cell would be highly undesirable since it caused an extra burden for initializing memory-cells and degraded the write and erase endurance cycles [4]. Here, for the first time, we designed a forming-free Cu-doped amorphous-carbon-oxide based ReRAM cell, which did not need a forming process and we reviewed the memory operation mechanism by understanding electrical and chemical properties of the Cu-doped a-COx based ReRAM cells. A typical a-COx based ReRAM-cell needed a forming process; i.e., a forming voltage of – 2.20 V and a set voltage of – 1.05 V, as shown in Fig. 1 (a). Otherwise, a Cu-doped a-COx based ReRAM-cell could achieve a forming-free process; i.e., a forming voltage (i.e. - 0.85 V) was the same as a set voltage (i.e. – 0.85 V), as shown in Fig. 1 (b). In addition, it demonstrated a write and erase endurance cycles of ~106 by sustaining a memory margin of ~1.3×102, being able to be utilized for a commercial nonvolatile memory-cell, as shown in Fig. 1(c). To clarify the forming-free mechanism, the depth profiles of C, Cu, and O atom in the Cu-doped a-COx memory cell were observed in detail under pristine, after set, and after reset process, which were obtained from intensity line-profiles of EELS/EDS elemental mapping images at C-K edges, O-K edges, Cu-Kα, Pt-La1, and W-La1. For the pristine state, C, Cu, and O atoms are uniformly distributed in the Cu-doped a-COx layer, as shown in Fig. 1(d). In addition, after a set process, since a negative voltage was applied to the top Pt electrode, Cu atoms evidently moved and segregated toward the top Pt electrode, as shown in a of Fig. 1(e), while O atoms evidently migrated and pile up toward the bottom W electrode, as shown in b of Fig. 1(e). This result means that the conductive C-C sp2 filaments in the Cu-doped a-COx layer were produced when oxygen atoms migrated and piled up toward bottom W electrode and the conductive Cu-atom filaments were formed in the Cu-doped a-COx layer since Cu atom moved and segregated toward the top Pt electrode. Hence, both conductive C-C sp2 filaments and Cu-atom filaments were generated simultaneously in the Cu-doped a-COx layer, achieving a set process without a forming process. On the other hand, after a reset process, since a positive voltage was applied to the top Pt electrode, Cu and O atoms were redistributed inside the Cu-doped a-COx, resulting in breaking both C-C sp2 filaments and Cu-atom filaments, as shown in a and b of Fig. 1(f). In our presentation, we will demonstrate and review the mechanisms between a set process without forming process and a reset process in detail by electrical and chemical composition depth profiles depending on the applied bias condition. In particular, we will demonstrate a different ReRAM behavior of the Cu-doped a-COx based ReRAM from a typical ReRAM or CBRAM. Acknowledgement This material is based upon work supported by the Ministry of Trade, Industry & Energy(MOTIE, Korea) under Industrial Technology Innovation Program (10068055). Reference [1] Matsui, C. et al. Integration 2019, 69, 62-74. [2] Hady, F. T. et al. Proceedings of the IEEE 2017, 105, (9), 1822-1833. [3] Santini, C. A. et al. Nature Communications 2015, 6, (1), 8600. [4] Skaja, K. et al. Scientific Reports 2018, 8. Figure 1

Recently, memristive devices (e.g. CBRAM and ReRAM etc.) have been proposed as an alternative to C-MOSFET based neuromorphic device (i.e. neuron and synapse) to achieve a high neuronal density and low power consumption. Among memristive devices, the conductive bridge neuron has been a great attention due to its area efficiency, low power consumption (< 500 fJ), and good C-MOS compatibility 1-3 . However, past researches have mainly focused on stochastic nature of conductive-bridge neurons. In particular, most of the stochastic conductive-bridge neuron have used capacitors to implement membrane potential, which requires a large integration area (~1000F2). In this works, integrate property of Al2O3-based cap-less conductive-bridge neuron was demonstrated which allows a cost-efficient neuromorphic chip by using a same process technology as a memristor synapse, as shown in Fig 1 (a). Note that the Al2O3-based cap-less conductive-bridge neuron was the same as that of the Al2O3-based memristor synapse. In addition, we investigated the effect of negative-differential-resistance (NDR) characteristic on integrate property for our proposed neuron, depending on the compliance current level (i.e. a shape of metallic filaments in neuron device). The NDR slope was adjusted by varying a compliance current of a Al2O3-based cap-less conductive-bridge neuron. The current compliance (Icc) of 1 mA showed the NDR slope of ~ 0.56 decade/V, as shown in Fig. 1(b). For all spike amplitude (i.e. -0.6~-1.0 V), the resistances of neuron device abruptly increased at a certain number of spikes, depending on the spike amplitude, and then it gradually increased with the number of spikes, as shown in Fig. 1(c). In addition, the spike number being necessary for achieving ~600 Ω decreased exponentially with increasing the number of spikes, as showed integrate property depending on input spike amplitude, as shown in Fig. 1(d). Otherwise, the current compliance (Icc) of 0.1 mA, which was 10 times less than Fig 1 (b) presented the NDR slope of ~ 0.23 decade/V, which was 2 times less than Fig. 1(b), as shown in Fig. 1(e). For all spikes amplitude, the resistance of neuron devices gradually increased with the number of spikes, wherein the resistance of neuron devices increased with the spike amplitude (i.e. negative voltage pulse amplitude), as shown in Fig. 1(f). The spike number being necessary for achieving ~10 kΩ decreased exponentially with increasing the number of spikes, as shown in Fig. 1(g). Comparing Fig. 1(d) with Fig. 1(g), the variation of the spike number being necessary for achieving ~600 Ω for the NDR slope of ~-0.56 decade/V was much less that for the spike number being necessary for achieving ~10 kΩ for the NDR slope of ~-0.23 decade/V. This result indicates that, for the Al2O3-based cap-less conductive-bridge neuron, the NDR slope dominantly determines the integrate nature. In our presentation, we will discuss the mechanism why the integrate property depended on the NDR slope via understanding a shape of conductive-metallic-filaments in Al2O3 layer, which determine an integrate property of neuron devices. In particular, it will be reported that the shape of conductive-metallic-filaments strongly depended on the metal vacancy concentration in binary oxide (i.e. Al2O3) layer. Acknowledgement This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIT) (No. 2016M3A7B4910249). Reference "IEEE Transactions on Emerging Topics in Computational Intelligence," in IEEE Transactions on Emerging Topics in Computational Intelligence, vol. 2, no. 5, pp. C2-C2, Oct. 2018, doi: 10.1109/TETCI.2018.2867377. Jang, B. Attarimashalkoubeh, A. Prakash, H. Hwang and Y. Jeong, "Scalable Neuron Circuit Using Conductive-Bridge RAM for Pattern Reconstructions," in IEEE Transactions on Electron Devices, vol. 63, no. 6, pp. 2610-2613, June 2016, doi: 10.1109/TED.2016.2549359. Palma, M. Suri, D. Querlioz, E. Vianello and B. De Salvo, "Stochastic neuron design using conductive bridge RAM," 2013 IEEE/ACM International Symposium on Nanoscale Architectures (NANOARCH), Brooklyn, NY, 2013, pp. 95-100, doi: 10.1109/NanoArch.2013.6623051. Figure 1

The efficacy of an experimentally designed cold chain container and a currently used styrofoam container was investigated with respect to important factors affecting the quality of fresh beef during storage under different conditions. The temperature in the TEPP-1 container was maintained at 5°C using a phase change material (PCM) during transport and delivery. During storage in the TEPP-1 container, no significant difference was observed in pH of beef, but color decreased slightly, which does not affect the desire to purchase. After storage for 7 days, the rate of VBN and TBA in the TEPP-1 container, was lower than that in the TEPP-2 container. Drip loss was lower in the TEPP-1 container (0.87%) than in the TEPP-2 container (1.78%). No significant changes were observed in microbal count until 4 days in either of the containers, but after storage for 7 days, the count increased significantly. Microbial count in TEPP-1 was 6.65 log CFU/mL and that in TEPP-2 was 7.62 log CFU/mL. The results of sensory evaluations indicated that the overall acceptability of beef after storage for 7 days was better in the TEPP-1 container than in the TEPP-2 container. The EPS container was inferior in comparison with TEPP-1 and TEPP-2. It was impossible to continue the experiment using the EPS container after 3 days. These results suggest that the experimentally designed TEPP-1 container can be used for beef transport and delivery for 7 days without significantly affecting the quality of beef.

This study analyses the determinants of residential location patterns of dual-worker households in the Seoul Metropolitan area (SMA) using the 2006 Household Travel Survey (HTS) data. To achieve this we employ two statistical methods: (1) a multinomial logit (MNL) model for analysing the residential location patterns of dual-worker households given the couples' predetermined joint workplaces; and (2) standard regression models to identify the determinants of couples' spatial separation (or proximity) between their homes and workplaces. Our major findings can be summarised as follows: (1) dual-worker households in the SMA are likely to choose a residence closer to the wife's workplace than the husband's; (2) the wife's commute length and duration are significantly shorter than the husband's; (3) the wife's family serving role is the most important factor in determining a location with greater proximity between the home and the wife's workplace; and (4) commute times better depict gender differences than co...

Nanoscale (∼28 nm) non-volatile multi-level conductive-bridging-random-access-memory (CBRAM) cells are developed by using a CuO solid-electrolyte, providing a Vset of ∼0.96 V, a Vreset of ∼−1.5 V, a ∼1 × 102 memory margin, ∼3 × 106 write/erase endurance cycles with 100 μs AC pulse, ∼6.63 years retention time at 85 °C, ∼100 ns writing speed, and multi-level (four-level) cell operation. Their non-volatile memory cell performance characteristics are intensively determined by studying material properties such as crystallinity and poly grain size of the CuO solid-electrolyte and are found to be independent of nanoscale memory cell size. In particular, the CuO solid-electrolyte-based CBRAM cell vertically connecting with p/n/p-type oxide (CuO/IGZO/CuO) selector shows the operation of 1S(selector)1R(resistor), demonstrating a possibility of cross-bar memory-cell array for realizing terabit-integration non-volatile memory cells.

We sought to compare the efficacy of interscalene brachial plexus bolus blockade (IBPBB) and patient-controlled interscalene indwelling catheter analgesia (PCIA) for postoperative pain management within 48 hours postoperatively in patients undergoing arthroscopic rotator cuff repairs (ARCR).Patients undergoing ARCR were randomized into 3 groups by postoperative analgesia method. The IBPBB group received a mixed solution of 16 mL of 0.75% ropivacaine and 4 mL of 2% lidocaine as a bolus postoperatively. The PCIA group received a 10-mL bolus solution of 0.75% ropivacaine (4 mL) and 5% dextrose water (6 mL) just after the operation and continuous infusion of this solution. The control received only meperidine as needed, 12.5 mg, intravenously. Visual analog scale (VAS) pain scores were evaluated for the first 48 hours postoperatively.For the first 2 hours postoperatively, VAS scores in the IBPBB group were significantly lower than in the PCIA group and control group, but at 12 and 24 hours postoperatively, VAS scores of the IBPBB group were significantly higher than the PCIA group (P .05). At 48 hours postoperatively, there was no significant difference in VAS scores among the 3 groups (P = .169). The method of analgesia was the only factor affecting pain scores at 24 hours postoperatively (P .05).IBPBB provided effective immediate postoperative analgesia until 6 hours postoperatively. Especially until postoperative 2 hours, the VAS pain score was less than 1 point in the IBPBB group; however, there was significant rebound pain at 12 hours after surgery. During the first 24 hours postoperatively, PCIA reduced postoperative pain without rebound pain. Surgeons should choose methods for control of postoperative pain considering the advantages and disadvantages of each analgesic method.

This study was conducted to compare the growth parameters of Listeria monocytogenes between beef isolates and Type strains in raw beef. Beef was artificially inoculated with 3 Log CFU/g levels and growth was measured during storage at various temperatures (5–25 °C) using conventional plating methods. The R2 value for lag time (λ) and specific growth rate (μ) were determined using modified-Gompertz model, which were greater than 0.98 at all storage temperature except at 5 °C. B f , A f , and RMSE showed acceptable ranges, showed that the models are suitable for the modeling the growth of L. monocytogenes. At all temperatures, the λ of L. monocytogenes beef isolates was shorter than that of the L. monocytogenes Type strains, and the μ of beef isolates was higher than that of Type strains. These results showed that growth pattern prediction of beef inoculated with L. monocytogenes beef isolates gives more actual results than with Type strains.

Ag-doped polymer (polyethylene oxide: PEO) conductive-bridging-random-access-memory (CBRAM) cell using inert Pt electrodes is a potential electro-forming free CBRAM cells in which electro-forming and electro-breaking of nanoscale (16~22-nm in diameter) conical or cylindrical Ag filaments occurs after a set or reset bias is applied. The dependency of the morphologies of the Ag filaments in the PEO polymer electrolyte indicates that the electro-formed Ag filaments bridging the Pt cathode and anode are generated by Ag+ ions drifting in the PEO polymer electrolyte toward the Pt anode and that Ag dendrites grow via a reduction process from the Pt anode, whereas electro-breaking of Ag filaments occurs through the oxidation of Ag atoms in the secondary dendrites and the drift of Ag+ ions toward the Pt cathode. The Ag doping concentration in the PEO polymer electrolyte determines the bipolar switching characteristics; i.e., the set voltage slightly decreases, while the reset voltage and memory margin greatly increases with the Ag doping concentration.

Recently, CMOS-based artificial neurons have successfully implemented neuron functions such as integrate and fire (IF) or leaky integrate and fire (LIF). In general, CMOS-based artificial neurons use capacitors to implement integration function of neuron. In this case, required RC time constant is about few milliseconds. And it requires large area of capacitor more than 1000F2. Therefore, it is necessary to develop capacitor-less artificial neuron to achieve high neuronal density. In this works, we implemented the integration function of neurons using CBRAM instead of capacitors. For the neuron device, CuTe/TiO2/TiN CBRAM cell was fabricated as shown in figure 1a. The neuron device has W bottom electrode with ~113 nm2 pattern size and 10 nm-thick TiO2 layer, and 200 nm-thick CuTe top electrode with 60 μm2 size. The TiO2-based CBRAM showed a typical bi-stable I-V curve as shown in figure 1b. The CBRAM cells showed negative differential resistance (NDR) during reset process. And it showed integrate characteristic when consecutive negative voltage pulse was induced to top electrode of the CBRAM cell. Figure 1c shows integrate characteristic of TiO2-based CBRAM cell. As shown in figure 1c, as the voltage pulse is applied, current gradually decreases. Also as amplitude of voltage pulse increased, the change of current became greater. Because the area of the CBRAM cell is only 4F2, it is expected that area of artificial neuron can be significantly reduced by replacing conventional capacitor based neuron. We will present how the CBRAM cell can be used to implement artificial neuron. Figure 1

Resistive random access memory (ReRAM) is one of the most promising candidates for the next-generation memory due to its simple structure, high switching speed and low power consumption [1]. Recently, there has been large interests in using carbon-baed material as solid electrolyte to overcome the limit of conventional metal-oxide memory. It has remarkable advantages over past metal-oxide memory such as high memory margin (Ion/Ioff > 100) and fast switching speed (20~50ns) [2]. However, the requirement of forming process to activate resisitive switching operation is one of the critical issues. Forming process may degrade the device switching characteristic and is not desirable for circuit design. In this study, forming-free characteristic of a-COx (amorphous carbon oxide) based ReRAM was observed by controlling the Cu-filament shape. To accurately control the Cu-atom concentration profile, insertion of Cu thin film was carried out in several ways. The first device, named A, was fabricated with the common ReRAM structure of Pt / Cu-doped a-COx / W. The second device, named B, was vertically stacked with the strcutrue of Pt / a-COx / Cu-doped a-COx / W. The third device, named C, was vertically stacked with the strcutrue of Pt / Cu-doped a-COx / a-COx / Cu-doped a-COx / W. The device was fabricated on W bottom electrode wafer patterned from 34 nm to 1921 nm by photo lithography process. The a-COx and other metals were deposited using dc magnetron sputter (PVD method). After the fabrication, the Cu-atom concentration profile was carefully examined using SIMS analysis to understand the correlation between forming-free chracteristic and Cu-filament shape. Forming-free characteristic device presented identical forming and set voltage of -0.85 V. Moreover, the result indicated that the high resistance state current of 2.41-7 A at 0.1 V, low resistance state current of 5.98-5 A at 0.1 V and the memory window margin (Ion/Ioff) of 2.48×102. In our study, we present that the precise design of the Cu-atom concentration profile of a-COx based ReRAM is the significant key to achieve the forming-free and stable non-volatile memory characteristic. [1] Daniele Ielmini, Semicond. Sci. Technol. 31 (2016) 063002 [2] Claudia A. Santini et al, NAT COMMUN, 6:8600 (2015) * This material is based upon work supported by the Ministry of Trade, Industry & Energy(MOTIE, Korea) under Industrial Technology Innovation Program (10068055). Figure 1

This study was conducted to assess the possibility of preserving frozen vegetables (Aster scaber, soybean sprouts, Chinese cabbage, green pumpkin, and Welsh onion) for a long period and of using them after such storage by measuring changes in quality due to their preservation. Various freshly harvested vegetables were blanched under optimal conditions (that were determined in a preliminary experiment), quick-frozen at for 24 h, and stored at . The change in the chromaticity of the frozen A. scaber, soybean sprouts, Chinese cabbage, green pumpkin, and Welsh onion did not vary. The hardness of the frozen A. scaber, green pumpkin, Chinese cabbage and Welsh onion did not change during the preservation period, whereas the hardness of the cotyledon and hypocotyl of the soybean sprouts significantly increased on the sixth month of their storage. The total bacterial counts of the A. scaber during the preservation period remained constant at CFU/g, whereas those of soybean sprouts, Chinese cabbage, green pumpkin, and Welsh onion decreased slightly to CFU/g. Coliform was not detected in any of the samples. The sensory evaluation showed that the preservation period that was used in this study did not significantly affect the marketability of the frozen vegetables. Therefore, it was considered that A. scaber, soybean sprouts, Chinese cabbage, green pumpkin, and Welsh onion can be safely preserved by freeze-storing them for up to 12 months.

We aimed to determine the quality indicators for quality prediction of frozen green pumpkin in distribution. Freshly harvested green pumpkin slices were blanched under optimal conditions (confirmed in a preliminary experiment), quick-frozen at for 24 h, and stored at 0, -5, -15, and . The correlation between each quality characteristic and the sensory preference rate was analyzed. There was a significant correlation between storage temperature-related drip rate and preference rate across all temperatures, except at. Hunter values, a and b, showed relatively high correlation coefficient values at -5, -15, and . Therefore, a change in the Hunter values should be considered when storing green pumpkin, because of their significant correlation with changes in the sensory preference and drip rates. Furthermore, they should be applied as quality indicators for the quality prediction of frozen green pumpkin in distribution.

The effects of the initial storage temperature and the PA film packaging on the extension of the shelf-life and the improvement of the postharvest storage quality of muskmelons were studied during their storage. Their storage quality was tested as follows: PA-film-wrapped muskmelons, stored at or for 30 days after their harvest, were kept at for 27 days (total: 57 days). On the fifth day of storage at (35th day overall), the weight loss reached 6.4% in the 7-control. However, the 2-PA showed the smallest loss of 2.2%. The soluble solids content and the acidity that were measured before the storage were and 0.26% in all the groups. After 27 days of storage at (on the 57th day overall), the values were highest in the 2-PA group with and 0.15%, respectively. Microorganisms were not detected at first; but on the fifth day of storage at (35th day overall), their values were 3.87 and 2.68 log CFU/g in the seven-control and the 2-PA, respectively. In other words, the 2-PA was found to be more effective in inhibiting microbial proliferation. In relation to sensory properties such as appearance, flavor, sweetness and chewiness, the 2-PA was superior to the other groups and was found to be most effective in improving the storability of muskmelons. In conclusion, it was found that low-temperature injury and fast storage quality deterioration did not occur in film-wrapped muskmelons that were stored at for 30 days after they were harvested.

This study was conducted to identify quality indicators to determine freshness of muskmelon during distribution. The correlation between each quality characteristic and organoleptic preference was analyzed after examining weight loss, firmness, soluble solid content, chromaticity, and respiration rate of and changes in the organoleptic characteristics during storage at 0, 10, 20 and after harvesting. The correlation between weight loss and preference according to the storage temperature was shown to be significant (p) under all temperature conditions, and was shown to be especially highly significant (p, a significant correlation between soluble-solid content and preference was shown. Therefore, it is right to apply the change in weight loss and firmness that indicated a high correlation with organoleptic preference as a quality indicator at all storage temperatures.

The chemical components of four muskmelons (Thankyou, Beauty, Picnic, and Symphony), according to the cultivars, were investigated during storage at for 28 days. After the storage period, the Picnic cultivar indicated a weight decrease of up to 4.70% whereas the Symphony cultivar showed the best weight maintenance during storage (1.02%). The Thankyou and Symphony cultivars had higher sugar content and acidity levels than the Beauty and Picnic cultivars during storage. While the Symphony and Beauty cultivars showed high hardness at the start of their storage, their hardness decreased much during storage while the Thankyou and Picnic cultivars showed little change in hardness during storage. Further, the Thankyou cultivar not only maintained its unique muskmelon yellow color but also showed lower microorganism growth than the other cultivars. The stem water loss seen in this cultivar, however, tends to be the first thing seen by the consumers and may thus determine its merchantable quality. In addition, as the Thankyou cultivar showed the least quality change during storage, it will be useful for the development of a technology for minimizing the moisture content of a muskmelon's stem.

This study was conducted to assess the effects of the removal of pesticide residues and microorganisms from yuja (Citrus junos Sieb ex Tanaka) using a surface-washing system, under the following washing conditions: 0.11, 0.42, and 0.73 m/s spray rotation speeds; 0.6, 0.9, and 1.2 MPa water pressure and 0.046, 0.092, and 0.138 m/s conveying speeds. Tap-water treatment was used as the control. The washing efficiency when using squid ink was highly correlated with the conveying speed and the spray rotation speed. In addition, the highest washing efficiency was achieved when the water pressure was 0.9 MPa. The microorganisms were reduced to 0.40 log CFU/g for the tap-water treatment, and all the treatments, except those at the conveying speed of 0.138 m/s and the spray rotation speed of 0.11 rpm (6.07 log CFU/g), produced higher removal efficiencies compared with the tap-water treatment. Reductions of 2.20 and 2.05 log CFU/g were achieved at the spray rotation speeds of 0.42 and 0.73, respectively. The largest reductions were observed when the conveying speed was 0.046 m/s. Higher pesticide residue removal efficiency values were obtained at slower conveying speeds and higher spray rotation speeds. Higher than 50% removal efficiency was achieved when the spray rotation speed was 0.046 m/s for spirodichlofen, deltamethrin, benomyl, thiophanate-methyl, and acequinocyl. Especially, the removal efficiency for benomyl and thiophanate-methyl was more than 90%. It can thus be concluded that the pesticide residues in yuja can be effectively reduced by washing the latter with a less-than-0.092-m/s conveying speed and a higher-than-0.42-m/s spray rotation speed.

Changes in the flavor of muskmelons stored at different temperatures were examined to judge aroma patterns during storage. A mass-spectrometry based electric nose was used to distinguish the subtle differences in the muskmelon's volatile compounds. The data were used for a discriminant function analysis (DFA), and then the partial least square algorithm was used for a quantitative analysis. Volatile components in the muskmelons increased with storage, and the first discriminant function score (DF1: r 2 =99.88%, F=3072.5) moved from a positive position to a negative position as the storage period increased. The proper point of maturity was anticipated as the 28 th day at 0 o C, 21 st day at 4 and 7 o C, and 14 th day at 10 o C. Also, using the DF1 score we could predict the general tendency (vitamin C, stem moisture, acidity) of the muskmelons. The electronic nose revealed that the major volatile compounds that changed during storage of the melons were ethyl ethyl acetate, butyl acetate, nonanol, dodecanoic acid, hexadecanoic acid and tricosane. The amount of volatile compounds detected increased during storage.

This study investigated the removal efficiency of pesticide residues and microorganisms, and changes of the amount of antioxidant compounds on yuja (Citrus junos Sieb ex Tanaka) by various washing methods. The washing methods were mechanical washing (MW), mechanical washing after soaking in SAcEW, strong acidic electrolyzed water (SAcEW+MW), and soaking detergent solution (DW), with a tap water washing (TW) as the control. After treatment of MW and SAcEW+MW, the microbial count were 3.71 and 2.66 log CFU/g, respectively. Compared with the TW treatment (5.77 log CFU /g), MW and SAcEW+MW treatments showed a higher reduction. As a result of pesticide residue, the SAcEW+MW removed 70.5–98.1% and was the most effective, regardless of the pesticides. Antioxdant activities, as measured by DPPH radical, ranged from 20.36 to 21.27% and there was no significant difference from the washing methods. The results of this study demonstrated that the SAcEW+MW was the most effective method for removing residual pesticides without affecting the quality of the yuja.

This study was conducted to develop a portable quality evaluation system of bee-honey by near infrared spectroscopic technique. Two kinds of bee-honeys from acacia and polyflower sources were tested in this study. The system consists of power supply, tungsten-halogen lamp, detector, and optical fiber probe. Performance of the system was analyzed by comparing the prediction accuracy of the laboratory spectrophotometer. Total of 346 spectra was divided into a calibration set and a prediction set. The PLS (Partial Least Squares) models were developed to predict the quality parameters of bee-honeys. Reflectance spectra, moisture contents, ash, invert sugar, sucrose, F/G ratio, HMF(hydroxy methyl furfural), and ratio of honeys were measured. The PLS models of the laboratory spectrophotometer showed good relationships between predicted and measured quality parameters of honeys in the wavelength range of 1.100~2.200 nm. The PLS analysis of the portable quality evaluation system showed good relationships between predicted and measured quality parameters of honeys in the wavelength range of 1.100~1.300 nm and 1.400~1.700 nm. The results showed the feasibility of the portable quality evaluation system to determine the quality parameters of bee-honey in the field during harvesting.

This study has been carried out aiming to have the materials for the use of selective control of specific functional component contents of vegetables and fruits by using LED light source in future through examination and analysis on the influence of LED light source (385 nm, 470 nm, 525 nm, and 630 nm) on the functional components and quality change of immature strawberry. Soluble solid content was 9.87% immediately after harvest and in 4 storage days, it gradually increased as 12.77% for the test group which is higher than control group of 10.97%. Acidity increased gradually during 3 storage days and then decreased a little at the 4th day from the beginning of storage irrespective of LED treatment for every group under treatment. Vitamin C, anthocyanin and total phenol content increased gradually for 4 storage days due to LED treatment for control group and test group. Each nutrient was as 54.28 mg/100 g, 6.89 mg/100 g, and 129.5 mg/100 g immediately after harvest and in 4 storage days, they appeared to be 78.70 mg/100 g, 12.48 mg/100 g, and 172.75 mg/100 g for the test group, higher than that of control group which were 71.64 mg/100 g, 9.89 mg/100 g, and 151.00 mg/100 g. Consequently, LED irradiation seemed to have affected the nutrients and quality of strawberry.

Resistive random access memory (ReRAM) is one of the most promising candidates for the next-generation memory due to its simple structure, high switching speed and low power consumption [1]. Despite of such advantages, its non-volatile characteristic strongly depends on memory cell size. To overcome the weakness, conductive bridging random access memory (CBRAM) cells have been researched as an alternative to oxygen-vacancy type ReRAM cells since CBRAM cells showed independence of non-volatile memory characteristics on the memory cell size [2]. However, CBRAM cells usually require a forming process to produce metal filaments in the solid-electrolyte before memory operation. It had a negative effect on the device since it reflects a high-power consumption. Thus, in this work, Cu2O-based CBRAM cells with forming-free characteristic were presented. In addition, we mainly focused on understanding the dependency of forming-free process on annealing temperature. To confirm the presence of forming process, the resistive switching device was fabricated on a Pt-bottom electrode (BE) with a 250nm via-hole pattern, and annealed at the temperature of as-sputtered, 150, 250 and 300 ˚C. As shown in Fig. 1(a) and 1(b), as-sputtered and 150 ˚C post annealing CBRAM cells demonstrated forming-free characteristic. However, reset process was not effectively work. For the case of 300 ˚C post annealing CBRAM cell, it required forming process as shown in Figure. 1(d). CBRAM cell with 250 ˚C post annealing demonstrated both bi-stable I-V characteristic and forming free characteristic. To understand the mechanism of the forming-free process at 250 ˚C post annealing, EDS line scanning/mapping were carried out on the CBRAM cells annealed at 150, 250, 300 and 400 ˚C repectively (Fig.2 (a)-(d)). According to the EDS analysis, the diffusion amount of Ag in the Cu2O layer decreases as the annealing temperature increases. This tendency can be attributed to the decrease in the number of metal vacancies sites. In the saturated case, as shown in Fig. 2(a) and 2(b), the reset process did not effectively work due to the excessive density of VCu 2- leaving not enough room for breaking the filament. In the optimal case, as shown in Fig. 2(c), forming-free characteristic and both set/reset process worked successfully due to the optimal gap between the concentrated area of Ag and the bottom electrode. In the deficient case, as shown in Fig. 2(d), the forming process was required due to the low density of VCu 2- in solid-electrolyte layer and the high gap between the concentrated area of Ag and bottom electrode. In our study, we report the annealing temperature (250 ˚C is the optimal condition in this study) is the significant key to achieve the forming-free and stable non-volatile characteristics via controlling the concentration of negatively charged Cu vacancies, where Ag ions can diffuse through. [1] Daniele Ielmini, Semicond. Sci. Technol. 31 (2016) 063002 [2] Ilia Valov, J. Phys. D: Appl. Phys. 46 (2013) 074005 This material is based upon work supported by the Ministry of Trade, Industry & Energy(MOTIE, Korea) under Industrial Technology Innovation Program (10068055). Figure 1