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BackgroundThe Korean Triage and Acuity Scale (KTAS) was developed based on the Canadian Emergency Department Triage and Acuity Scale. In patients with pain, to determine the KTAS level, the pain scale is considered; however, since the degree of pain is subjective, this may affect the accuracy of KTAS. The purpose of this study was to evaluate the accuracy of KTAS in predicting patient's severity with the degree of pain used as a modifier.MethodA retrospective observational cohort study was conducted in an urban tertiary hospital emergency department (ED). We investigated patients over 16 years old from January to June 2016. The patients were divided into the pain and non-pain groups according to whether the degree of pain was used as a modifier or not. We compared the predictive power of KTAS on the urgency of patients between the two groups. Acute area registration in the ED, emergency procedure, emergency operation, hospitalization, intensive care unit admission, and 7-day mortality were used as markers to determine urgent patients.ResultsOverall, 24,253 patients were included in the study, with 9,175 (37.8%) in the pain group. The proportions of patients with KTAS 1-3 were 61.4% in the pain and 75.6% in the non-pain groups. Among patients with KTAS 2-3, the proportion of urgent patients was higher in the non-pain group than the pain group (pConclusionsConsidering the degree of pain with KTAS led to overestimation of patient severity and had a negative impact on the predictability of KTAS for urgent patients.

We investigated the utility of near-infrared (NIR) light devices for peripheral intravenous cannulation (PIVC) in pediatric patients. We searched three databases, MEDLINE, EMBASE, and the Cochrane CENTRAL. Randomized controlled trials that compared PIVC using NIR light devices and the "traditional" method (with no assistive device) were included. The primary outcome was a failure rate at the first attempt, and the effect size was measured by the risk ratio for failure. Subgroup analysis was performed according to control group risk for failure at first attempt as an indicator of difficult procedure (low vs. high). Eleven studies were included in the meta-analysis. There was no significant difference in the primary outcome between the two methods (risk ratio 1.03, confidence interval 0.89-1.20, IUsing NIR light devices did not have an impact on overall failure rate at the first attempt at PIVC in pediatric patients. What is Known: • Near-infrared light devices have been used to help vascular access especially for the pediatric patients. But, their utilities reported in previous studies were conflicting. What is New: • From this study, we could not find out overall benefit of using near-infrared light devices for pediatric peripheral intravenous cannulation. But, this device might be useful for the patients in a difficult condition of successful cannulation.

A 512 Mb diode-switch PRAM has been developed in a 90 nm CMOS technology. The vertical diode-switch using the SEG technology has achieved minimum cell size and disturbance-free core operation. A core configuration, read/write circuit techniques, and a charge-pump system for the diode-switch PRAM are proposed. The 512 Mb PRAM has achieved read throughput of 266 MB/s through the proposed schemes. The write throughput was 0.54 MB/s in internal x2 write mode, and increased to 4.64 MB/s with x16 accelerated write mode at 1.8 V supply.

Background: In the clinical setting, the dispersed practitioners’ attention often leads to decreased competence in their performance. We aimed to investigate the effect of distracted practitioners on the quality of chest compression during cardiopulmonary resuscitation. Methods: A randomized controlled crossover simulation study was conducted. Participants were recruited from among doctors, nurses, and paramedics working in a university tertiary hospital. The paced auditory serial addition test (PASAT) was used as a tool for distracting participants. In the crossover design, each participant played 2 scenarios with a 20-minute time gap, by a random order; 2-minute continuous chest compressions with and without PASAT being conducted. The primary outcome was the percentage of compression with an adequate compression rate. Secondary outcomes were the percentage of compression with adequate depth, the percentage of compression with full chest wall recoil, mean compression rate (per minute), mean compression depth, and subjective difficulty of chest compression. Results: Forty-four participants were enrolled, and all of them completed the study. It was found that the percentage of compression with an adequate compression rate was lower when the PASAT was conducted. Although there was no difference in the percentage of compression with adequate depth (P = .88), the percentage of compression with complete chest recoil was lower when PASAT was conducted. In addition, while the mean compression rate was higher when PASAT was conducted, the mean compression depth was not significantly different (P = .65). The subjective difficulty was not different (P = .69). Conclusions: Health care providers who are distracted have a negative effect on the quality of chest compression, in terms of its rate and chest wall recoil. Trial registration: www.ClinicalTrials.gov, NCT03124290.

Objectives The ideal invasive management as initial approach for pneumothorax (PTX) is still under debate. The purpose of this systematic review and meta-analysis was to examine the evidence for the effectiveness of intercostal tube drainage and other various invasive methods as the initial approach to all subtypes of PTX in adults. Methods Three databases were searched from inception to May 29, 2016: MEDLINE, EMBASE, and the Cochrane CENTRAL. Randomised controlled trials that evaluated intercostal tube drainage as the control and various invasive methods as the intervention for the initial approach to PTX in adults were included. The primary outcome was the early success rate of each method, and the risk ratios (RRs) were used for an effect size measure. The secondary outcomes were recurrence rate, hospitalization rate, hospital stay, and complications. Results Seven studies met our inclusion criteria. Interventions were aspiration in six studies and catheterization connected to a one-way valve in one study. Meta-analyses were conducted for early success rate, recurrence rate, hospitalization rate, and hospital stay. Aspiration was inferior to intercostal tube drainage in terms of early success rate (RR = 0.82, confidence interval [CI] = 0.72 to 0.95, I2 = 0%). While aspiration and intercostal tube drainage showed no significant difference in the recurrence rate (RR = 0.84, CI = 0.57 to 1.23, I2 = 0%), aspiration had shorter hospital stay than intercostal tube drainage (mean difference = -1.73, CI = -2.33 to -1.13, I2 = 0%). Aspiration had lower hospitalization rate than intercostal tube drainage, but marked heterogeneity was present (RR = 0.38, CI = 0.19 to 0.76, I2 = 85%). Conclusion Aspiration was inferior to intercostal tube drainage in terms of early resolution, but it had shorter hospital stay. The recurrence rate of aspiration and intercostal tube drainage did not differ significantly. The efficacy of catheterization connected to a one-way valve was inconclusive because of the small number of relevant studies. (Registration of study protocol: PROSPERO, CRD42016037866)

It was investigated that a new dry cleaning methodology named laser shock cleaning could be applied to remove the particles from the wafer surface. The γ-alumina particles of 0.05 μm in diameter were deposited uniformly on bare Si wafer surface by aerosol spray method. The number of particles on wafer surface was measured by surface scanner before and after cleaning. It was found that most of the particles on the wafer surface were removed after dry shock cleaning using Nd:YAG laser. The average removal efficiency of the particles was over 90%, and the larger particles are easier to remove from the surface due to their smaller adhesion force. The removal efficiency of particles increased slightly as the particle size was to be larger.

Peripheral venous access in infants and children is technically challenging, because their veins are small and located deep in subcutaneous tissue, which makes them difficult to palpate or visualize. The VeinViewer® (Luminetx Corporation, Memphis, TN, USA) is a near-infrared light device that delineates the running course of subcutaneous veins. In this study, we investigated whether the use of the VeinViewer® in infants and children facilitated peripheral venous access, especially in difficult cases. This study was a randomized, controlled trial of a convenience sample of pediatric patients between the ages of 1 month and 16 years who required peripheral venous access in the pediatric ward. Prior to randomization, difficult intravenous access (DIVA) score, a four-variable clinical prediction rule for first-attempt success, was estimated. We compared the first-attempt success rates and procedural times between the VeinViewer® group and a control group. We evaluated 111 patients: 54 in the VeinViewer® group and 57 in the control group. Patient demographics and factors related to the success of vein access were similar for both groups. The overall first-attempt success rate was 69.4%: i.e., 77/111 in the VeinViewer® group and 38/57 in the control group, a difference that was not statistically significant. However, the first-attempt success rate increased from 5/20 in the control group to 14/24 in the VeinViewer® group for difficult veins with a DIVA score greater than 4 (p = 0.026). There were no significant differences in procedural time between the two groups. Conclusion: The VeinViewer® facilitated peripheral venous access for pediatric patients with difficult veins, which enhanced first-attempt success rates.

Post exposure bake (PEB) is the most important process for chemically amplified resist to make nano-scale device. According to 2007 ITRS roadmap, critical dimension (CD) should be controlled below 1.9 nm on sub-22 nm half pitch in whole process of semiconductor. But CD error can be happened during the whole processes of exposure, PEB, develop, and etching. For this study, we assumed PEB process is just one of four processes, so that we take arithmetic mean error of four process, namely, ~ 0.5 nm (1.9 nm / 4) CD error should be controlled during PEB, even though PEB is the critical processes for CD control. 1 degree PEB temperature difference would make 3 nm CD change, so that we should control the temperature variation below 0.2 degree to control CD variation within 0.5 nm for 22 nm node. However, temperatures on the whole hot plate is not perfectly uniform. The temperature at the heat source is higher than that at the position with no heat source. Such a temperature difference inside hot plate would be directly transferred to the wafer and eventually inside the photoresist. Thus the temperature distribution inside the whole photoresist would be non-uniform, and this would make non-uniform CD distribution eventually. We calculated the temperature distribution within the hot plate in accordance with the position and structure of heat source. We also calculated the temperature distribution inside photoresist by considering the heat conduction. In addition to that, we estimated the possible CD variation caused by the non-uniform temperature distribution within photoresist on wafer.

According to the ITRS roadmap, DRAM half pitch (hp) will reach to 32 and 20 nm in 2012 and 2017 respectively. However, it is difficult to make sub-40 nm node by single exposure technology with currently available 1.35 numerical aperture (NA) ArF immersion lithography. Although it is expected to enable 32 nm hp with either double patterning technology or extreme ultra-violet lithography, there are many problems to be solved with cost reduction. Thus, the study of high-index fluid immersion technology should be pursued simultaneously. ArF water immersion systems with 1.35 NA have already introduced for 40 nm hp production. ArF immersion lithography using high-index materials is being researched for the next generation lithography. Currently, many studies are undergoing in order to increase NA with higher index fluid and lens in immersion technology. The combination of LuAG (n=2.14) and third-generation fluid could be used to make 1.55 NA. This combination with 0.25 k1, 32 nm hp can be obtained by single exposure technology. In order to check the realization of this process and to check the possible process hurdles for this high NA single exposure technology, 32 nm hp with 1:1 line and space patterning is tried. Various illumination conditions are tried to make 1:1 32 nm hp and the exposure and develop conditions are varied to check whether this single exposure can give processible window. As a result, 32 nm hp can be obtained by single exposure technology with 1.55 NA.

According to ITRS road map, it will be achieved 22 nm half pitch until 2016. However, it is hard to make although EUV, high index immersion. We have positive strategy for 22 nm half pitch with immersion and double patterning and RRP. We can make 22 nm half-pitch with hard mask by using RRP that can shrink trench pattern and double patterning that can get over resolution limitation. Immersion technology can make 44 nm half pitch in NA 1.35. When the developed resist profile can be reflow, so line is increased and space is decreased. It can be 22 nm trench pattern with 66 nm width by using RRP. Hence, we can obtain 66 nm line and 22nm space pattern by etching. And then, we can obtain 22 nm half pitch after doing double patterning. We tried to evaluate this strategy by commercial and home-made simulator.

Making a sub-32 nm line and space pattern is the most important issue in semiconductor process. Specially, it is important to make line and space pattern when the device type is NAND flash memory because the unit cell is mostly composed of line and space pattern. Double patterning method is regarded as the most promising technology for sub-32 nm half-pitch node. However, double patterning method is expensive for the production and heavy data split is required. In order to make cheaper and easier patterning, we suggest a resist reflow process (RRP) method for 32 nm 1:1 line and space pattern. It is easier to make 1:3 pitch than 1:1 pitch line and space in terms of aerial image, and RRP can make 1:3 pitch aerial image to 1:1 resist image. We used home-made RRP simulation based on Navier-Stokes equation including surface tension effect. Solid-E is used for optical simulation, and e-beam lithography is used for the experiment to check the concept.

Making a sub-100 nm contact hole pattern is one of the difficult issues in semiconductor process. Compared with another fabrication process, resist reflow process is a good method to obtain very high resolution contact hole. However it is not easy to predict the actual reflow result by simulation because very complex physics and/or chemistry are involved in resist reflow process. We must know accurate physical and chemical constant values and many fabrication variables for better prediction. We made resist reflow simulation tool to predict approximate resist reflow as functions of pitch, temperature, time, array, and so on. We were able to see the simulated top view, side view and the changed hole size. We used Navier-Stokes equation for resist reflow. We had varied the reflow time, temperature, surface tension, and 3-dimensional volume effect for old model. However the photoresist adhesion is another very important factor that was not included in the old model. So the adhesion effect was added on Navier-Stokes equation and found that there was a distinctive difference in reflowed resist profile and the contact hole width compared to the case of no adhesion effect.

For the first time, S-RCAT (sphere-shaped-recess-channel-array transistor) technology has been successfully developed in a 2Gb density DRAM with 70nm feature size. It is a modified structure of the RCAT (recess-channel-array transistor) and shows an excellent scalability of recessed-channel structure to sub-50nm feature size. The S-RCAT demonstrated superior characteristics in DIBL, subthreshold swing (SW), body effect, junction leakage current and data retention time, comparing to the RCAT structure, in this paper, S-RCAT is proved to be the most promising DRAM array transistor suitable for sub-50nm and mobile applications.

According to the International Technology Roadmap for Semiconductors (ITRS), memory half pitch (hp) will reach 32 and 20 nm by 2012 and 2017, respectively. However, it is difficult to fabricate a sub-40 nm node using single-exposure technology with the currently available 1.35-numerical-aperture (NA) ArF immersion lithography. Although it is expected that either double patterning technology or extreme ultraviolet lithography will enable the realization of 32 nm hp, there are still many problems that need to be solved regarding cost reduction. Thus, the study of high-index fluid immersion technology should be pursued simultaneously. ArF water immersion systems with 1.35 NA have already been introduced for 40-nm-hp production. ArF immersion lithography using high-index materials is currently being studied for next-generation lithography. Currently, many studies are being undertaken in order to increase NA for a high-index fluid and a lens in immersion technology. The combination of LuAG (n = 2.14) and a third-generation fluid could be used to realize 1.55 NA. This combination of 0.25k1 and 32 nm hp can be obtained using single-exposure technology. In order to determine the feasibility of this process and possible process hurdles for this high-NA single-exposure technology, 32 nm hp with a 1:1 line and space pattern is tested. Various illumination conditions are tested to realize 1:1 32 nm hp, and the exposure and development conditions are varied to determine whether this single exposure can provide a processible window. As a result, 32 nm hp could be obtained by single-exposure technology with 1.55 NA.

Contact hole (CH) patterning, especially for the sub-50 nm node, is one of the most difficult techniques in optical lithography. The resist reflow process (RRP) can be used to obtain smaller CHs. RRP is a simple technique in which the resist, after the development process, is baked above the glass transition temperature. Heating causes resist flow, and smaller CHs can be obtained. However, RRP is an unmanageable method because of the CH offset caused by the pattern position in random array CHs. Thus we tried optical proximity correction to find a uniform critical dimension (CD) for every CH, and we obtained uniform CDs for every CH after RRP. However, we still have a CH position shift problem. Because of the difference in the amount of resist that flows into the hole in a random array during the reflow process, position shift occurs. This position shift causes an overlay error, which may exceed the overlay error budget suggested in the ITRS roadmap. In this work, we try to determine not only uniform CD size of each CH, but also the optimum conditions for correcting CH position shift by homemade simulation. Moreover, we checked the behavior of CH position shift by e-beam lithography. Consequently, we confirmed that CHs shifted in a receding direction from each other, and obtained sub-50 nm CHs in a random array by considering the position shift by simulation and experiment.