Earticle

As electric vehicles spread, electric vehicle fires continue to occur. The main cause of these electric vehicle fires is battery overload caused by battery management system (BMS) malfunction. Existing BMS measures the voltage of the battery by physically connecting each battery cell and the controller, but in electric vehicles, the battery operates up to 1,000V or more. In this high-voltage environment, the BMS, which is the circuit that manages the battery, operates at a low voltage of 5V or less. Therefore, if a high battery voltage has an incorrect effect on the BMS board operating at a low voltage, the BMS board is destroyed, leading to battery malfunction and battery explosion. In order to compensate for these problems, indirect measurement technology that physically isolates the battery cell and the low-voltage control board is important. The indirect measurement method of the isolation structure obtained in previous research for safe battery voltage measurement resulted in battery cell voltage monitoring results of several mV to tens of mV due to errors due to device imbalance and temperature characteristics of the battery cells found in the parallel structure. To solve this problem, we were able to overcome inaccurate battery cell voltage monitoring results due to device imbalance and temperature characteristic differences at once by sequentially monitoring the battery voltage of all battery cells through a single indirect measurement path. In the process of recognizing battery cell voltage, changes in monitoring voltage depending on temperature must be compensated. However, the existing temperature compensation circuit used a temperature sensor to compensate for the temperature with a resistance value, but accurate compensation was difficult. In this paper, in order to accurately compensate for temperature, the reference voltage (REF_V) was created internally by dividing it into 15 steps from 4.2V to 3.2V, and the temperature can be compensated by applying the voltage (REF_V), so the battery voltage can be recognized accurately at any temperature. I could do it. Additionally, the internal clock oscillator that generates the clock internally is designed to operate at 1khz. As a result of the design, temperature compensation was performed on 16 battery cells, and when operating at an internal clock of 1khz, all 16 battery cells and reference voltages could be monitored in 2 seconds. The research results of this paper automatically generate temperature compensation. voltage REF_V and battery cell voltage along with code values, allowing BMS operation to be accurately known without CPU control.

본 연구는 전라남도 신안군 흑산면 매물도에서 방목염소 구제 이후 식물상과 주요 식생의 변화에 대한 모 니터링을 실시하였다. 식물상과 식생조사를 2016년 6월부터 9월까지 총 3회에 걸쳐 실시하였다. 그 결과, 관속식물 은 36과 71속 63종 1아종 10변종 1품종으로 총 75분류군이었다. 조사된 식물 중 식물구계학적 특정식물종은 V 등 급 1분류군, III등급 3분류군, I등급 13분류군으로 총 17개분류군이 확인되었다. 귀화식물은 11분류군이 확인되었다. 귀화율은 14.7%이었으며, 도시화지수는 3.4%로 산출되었다. 매물도의 주요 식물군락은 목본으로는 후박나무군락, 동 백나무군락, 까마귀쪽나무군락, 팽나무-까마귀쪽나무군락이 자생하였고, 초본으로는 고사리군락, 억새군락, 명아주군락, 유채-갯장구채군락, 망초군락, 암벽식생, 미국자리공군락 등이 나타났다. 매물도의 산림식생 중 가장 넓은 면적을 차 지하고 있는 식생군락은 까마귀쪽나무군락으로 총 20.21%, 27,040.65 m2를 차지하고 있는 것으로 조사되었다. 그 다음으로 암벽식생이 13.53%, 유채-갯장구채군락이 12.50%로 조사되었다.

This study was carried out to monitor the changes of flora and major vegetation after goats grazing eradication located in Maemuldo, heuksan-myeon, Shinan-gun, Jeollanamdo. The study was performed from June to September 2016. Vascular plants were summarized as 75 taxa including 36 families, 71 genera, 63 species, 1 subspecies, 10 varieties and 1 forms. 17 taxa were listed as specific plants based on phytogeographical distribution in the investigated area. The exotic plant species were recorded as 11 taxa. The Naturalization Ratio and Urbanization Index were recorded as 14.7%, and 3.4%. Litsea japonica community accounted for the biggest among all the forest communities in Maemuldo with 20.21% or 27,040.65 m2. It was followed by Rock vegetation community with 13.55%, Brassica napus- Melandryum oldhamianum community with 12.50%.

최근 마이크로 아키텍처의 취약점을 이용하여 내부의 비밀 정보를 노출시키는 캐시 부채널 공격들이 제안되었다. 캐시 부채널 공격 중 Flush+Reload 공격은 높은 해상도와 낮은 노이즈 특성으로 인해 여러 악의적 응용 공격에 활용되고 있다. 본 논문에서는 CPU 캐시 활동을 관측할 수 있는 PCM(Performance Counter Monitor) 기능을 이용하여 캐시 기반 부채널 공격을 찾아낼 수 있는 탐지기를 구현하였다. 특히, Spectre 공격과 AES 암호 연산 중 비밀 키 추출 공격이 발생했을 때를 가정하여 PCM 카운터 값의 변화를 관측하였다. 실험 결과, PCM의 4가지 카운터 특성이 캐시 부채널 공격에 크게 반응함을 확인하였고, SVM(Support Vector Machine). RF(Random Forest), MLP(Multi Level Perceptron)와 같은 머신 러닝 기반 검출기를 통해 높은 정확도로 캐시 부채널 공격을 탐지할 수 있었다.

Recently, several cache side channel attacks have been proposed to extract secret information by exploiting design flaws of the microarchitecture. The Flush+Reload attack, one of the cache side channel attack, can be applied to malicious application attacks due to its properties of high resolution and low noise. In this paper, we proposed a detection system, which detects the cache-based attacks using the PCM(Performance Counter Monitor) for monitoring CPU cache activity. Especially, we observed the variation of each counter value of PCM in case of two kinds of attacks, Spectre attack and secret recovering attack during AES encryption. As a result, we found that four hardware counters were sensitive to cache side channel attacks. Our detector based on machine learning including SVM(Support Vector Machine), RF(Random Forest) and MLP(Multi Level Perceptron) can detect the cache side channel attacks with high detection accuracy.

Protein -surfactant interactions have been investigate by measuring ζ-potential of $\beta$-lactoglobulin-coated emulsion droplets and $\beta$-lactoglobulin in solution in the rpesenceof surfactant, with particular emphasis on the effect of protein heat treatment(7$0^{\circ}C$, 30min). When ionic surfactant (SDS or DATEM) is added to the protein solution, the ζ-potential of the mixture is found to increase with increasing surfactant concentration, indicating surfactant binding to the protein molecules. For heat-denatured protein,it has been observed that the ζ-potential tends to be lower than that of the native protein. The effect of surfactant on emulsions is rather complicated .With SDS, small amounts of surfactant addition induce a sharp increase in zeta potential arising from the specific interaction of surfactant with protein. With further surfacant addition, there is a gradual reductio in the ζ-potential, presumably caused by the displacement of adsorped protein (and protein-surfactant complex) from the emulsion droplet surfac by the excess of SDS molecules. At even higher surfactant concentrations, the measured zeta potential appears to increase slightly, possibly due to the formation of a surfactant measured zeta potential appears to increase slightly, possibly due to the formation of surfactant micellar structure at the oil droplet surface. This behaviour contrastswith the results of the corresponding systems containing the anionic emulsifier DATEM, in which the ζ-potential of the system is found to increase continuously with R, particularly at very low surfactant concentration. Overall, such behaviour is consisten with a combination of complexation and competitive displacement between surfactant and protein occurring at the oil-water interface. In addition, it has also been found that above the CMC, there is a time-dependent increase in the negative ζ-potential of emulsion droplets in solutions of SDS, possibly due to the solublization of oil droplets into surfactant micelles in the aqueous bulk phase.

Fluence monitor(F/M)는 조사 시편을 원자로의 노심에 넣은 후 방사화 된 조사 시편의 방사능을 측정한 후 역산하여 중성자의 선량을 계산하는 기법으로 원자로내의 중성자 분포를 조사하기 위하여 반드시 필요한 기술이다. 이 기술은 중성자에 대한 에너지 스펙트럼 측정이 간접적으로 가능하며, 현존하는 중성자 분포 측정 기법 중에서 우수한 정밀도를 지니고 있다. 하나로(HANARO)에서 수행하는 재료조사 시험에서의 중성자량 측정을 위하여 본 연구에서는 지름 0.1 mm, 길이 3 mm 미만의 질량 150~200 ㎍ 범위, 순도 99.9% 이상의 Fe, Ni, Ti 와이어를 F/M 시편으로 사용하였다. 이 시편은 알루미늄 캡슐에 봉입하여 30 MW 의 하나로 OR5공에 약 25일간 조사하였다. 조사를 마친 시편은 high purity germanium (HPGe) detector를 이용하여 감마선을 측정하였고, SAND-II code로 reaction rate와 중성자 cross-section등을 고려하여 fluence monitor 위치에서의 중성자 플루언스를 계산하였다. F/M이 장착 되었던 하나로 OR5공의 중성자 플루언스 값은 MCNP 코드를 이용하여 계산된 결과를 사용하였으며, SAND-II code로 장착된 F/M 위치에서의 중성자 플루언스를 계산하여 적용된 시편의 reaction에 따른 결과값의 차이를 비교 분석하였다.

The neutron fluence measurement and evaluation technology is very important for material irradiation test. The most essential technology in this study is the neutron irradiation evaluation method using a fluence monitor. The fluence monitors were fabricated with metal wires of the purity ≥ 99.9%, whose dimensions were 0.1mm diameter, about 3 mm length, and around 150-200 μg mass range. Three wire samples (Fe, Ni, Ti) were prepared for one irradiation aluminum capsule. Five capsules were irradiated in the OR5 hole of the HANARO reactor at 30 MW power for about 25 days. After irradiation tests, radiation activities were measured with the high purity germanium (HPGe) detector. The reaction rates were calculated by using the measured radiation activity data, and then neutron fluence were obtained from the reaction rates and the weighted neutron cross section with calculated neutron spectrum at the fluence monitor position.

The purpose of this study was to develop a personalized SMT (smart monitor target) game interface for game users who enjoy airsoft sports as individual purchases of SMT have increased since the advent of the untouched era. For this study, the UX (user experience) of the game interface was designed based on previous research. In particular, the personalized game service was reinforced by adding the CP (command post) of the SMT system that performs the home function of the console game, which was intended to help the user maintain immersed in the game in the personalized space of the SMT. Major design elements for the SMT game interface included layout, color, graphics, buttons, and text, and the interface design was proceeded based on them. After composing a grid with a layout in which the tab function was applied to the interface with a vertical three-segment structure and the outer margin value secured, the military camouflage pattern and texture were applied to the colored tone to perform graphics work. Targets and thumbnails were produced as illustrations using experts to ensure the consistency of the interface, and then function buttons and texts on each page were used concisely for intuitive information delivery. The design sources organized in this way were developed using the Unity engine. In the future, we hope that game user-centered personalized interfaces will continue to develop and provide differentiated services unique to SMT systems in the airsoft gun market.

We examine the effects of several corporate governance and monitoring mechanisms on the choice of dual-class status and firm performance of dual-class firms. Employing 736 firms that implemented dual-class and 7,027 single-class firms during the period 1996-2002, we find that dual-class firms tend to be larger, higher director ownership and institutional ownership, lower blockholdings, and smaller fraction of independent outside directors on their board than those of single-class firms. In addition, we observe that dual-class firms are followed by smaller number of security analysts. After correcting for endogeneity bias, our regression results show that firms with higher analyst coverage and lower wedge, measured as the difference between voting rights and cash flow rights, are strongly associated with Tobin’s q. In contrast, blockholders’ ownership, board independence, and institutional ownership play a relatively insignificant role in enhancing Tobin’s q. We interpret our results to mean that security analysts are the most effective monitoring mechanism that influence both the dual-class choice and firm performance. Our results are not attributed either to the difference in firm size or to an industry effect.

I examine the simultaneous associations between institutional ownership and capital structure of a firm. I find that a firm’s leverage decreases when institutional ownership increases. This result implies that a firm reduces its debt level as institutional monitoring substitutes for the external debt monitoring, and indirectly suggests institutional investors’ activism. More importantly, I also find that a firm’s suboptimal leverage increases when the institutional ownership increases, and institutional ownership decreases when a firm’s suboptimal leverage increases. This finding directly shows that institutional investors not only actively monitor the management but they also passively sell their shares when dissatisfied with the management. In addition, I find that the monitoring evidence on a firm’s leverage and suboptimal leverage are more pronounced when the institutional investors are less likely to have business relationships with a firm or the information asymmetry is high in the market.

몰입감은 게임을 플레이 하는데 중요한 요소이며 궁극적으로 게임 자체의 성공을 좌우하는 재 미 그 자체아 결부되기도 한다. 시각적 영역과 밀접한 연관이 있는 해상도는 게임 개발에 있어서 비중있는 요소이며 게임을 개발할 때 염두에 두어야 할 요소이기도 하다. 그래픽 기술의 발전은 하드웨어 발전과 함께해 왔으며, 대부분의 게임은 현재 고해상도의 고품질 그래픽으로 개발되고 있다. 현재 다양한 사용자들의 다양한 해상도 정보 분석 및 시장 조사는 게임 개발자들에게 효과 적인 정보를 제공해 줄 것이며 연구 가치가 있다고 할 수 있다. 본 연구는 지난 4년 간 네이버 소프트웨어 문서분야에서 가장 많은 다운로드 수를 기록하고 있는 문서 뷰어인 'DAVU'의 사용자 정보를 통해 한국인 IT사용자들의 평균 해상도를 분석한다. 'DAVU'는 국내 통합 뷰어 솔루션으로 2014년 국내 문서 및 이미지 뷰어 솔루션을 통해 서비스를 시작했으며 사용자가 뷰어를 실행할 때 개인정보를 제외한 사용자 정보(해상도, 파일 포맷, OS, IE정보 등)를 서버로 전송하여 집계가 가능하다. 이 연구는게임 및 소프트웨어뿐만 아니라 모니터 하드웨어 산업에도 효율적 정보를 제공해 주는 연구가 될 것이다.

Immersion is a very important factor in playing games, and ultimately it is linked to fun, which in turn affects the success of the game itself. The resolution, which is a visual area in this immersion, is a very important factor, and it is also a factor that must be kept in mind when developing a game. The development of graphics technology has been accompanied by the development of hardware, and most games are now being developed with high-resolution, high-quality graphics. Currently, analysis and market research on how various users contact content at various resolutions will provide effective information to game developers and they are worth researching. This study analyzes the resolution of Korean average users through the user information of 'DAVU' which is the number one document viewer in Naver Software Data Room for the last 3 years. ‘DAVU’is a domestic integrated viewer solution, launched its service in 2014 with a domestic document and image viewer solution. When the user runs the viewer user without environment information (resolution, file format, OS, IE information, etc.) , it is transmitted to server and aggregated. It has been ranked No. 1 in the Naver Software Viewer category for more than two years, with 16 million total users. The analysis of computer users' resolution will be an effective study not only for games and software but also for the monitor hardware industry.

Background: For an accelerator-based BNCT, we have fabricated a new detector consisting of quartz optical fibers that have excellent radiation-resistant characteristics. Materials and Methods: The developed detectors were irradiated at Kyoto University Research Reactor. Results and Discussion: The experimental results showed that the new detector had good output linearity for the neutron intensity, and the response of the new detector did not decrease during the irradiation. Conclusion: The new detector consisting of quartz optical fibers can be applied to measurement of neutron field of an accelerator-based BNCT.

The talk test (TT) is subjective method to measure exercise intensity in costless and feasible manner, compared to sophisticated laboratory equipment. We attempted to investigate whether the TT was a valid method for evaluation of exercise intensity, by comparing with values derived from various physiologic markers during cardiopulmonary ex-ercise testing on treadmill in healthy population. A total of 17 healthy subjects (12 males and 5 females) participated in this study. The TT was applied, which consisted of 3-stages difficulties demanding respiratory load while they performed the cardiopulmonary exercise testing on treadmill. In each of the TT stages, ergospirometric and psychophysio-logic response marker were collected such as heart rate, oxygen con-sumption, respiratory exchange ratio, minute ventilation, carbon dioxide output, tidal volume, respiratory rate, and rating of perceived exertion of breathing. Statistical analyses revealed a significant difference of all dependent variables in each of three TT stages, comparing with the resting phase before the TT. The TT showed strong correlation coeffi-cient with all variables except for rating of perceived exertion during the resting phase before the TT. According to increase of exercise in-tensity, all dependent variables showed a linear tendency with the stages of the TT. Our findings indicated that each of the TT stages was strongly correlated with ergospirometric variables as well as psycho-physiologic response during cardiopulmonary exercise testing on treadmill. We suggested that the TT can be used to evaluate and pre-scribe exercise intensity of aerobic activity in cardiovascular and pul-monary rehabilitation settings.

Background: This study aims to calculate detector positions as a design of a radioactive source localizing radiation portal monitor (RPM) system using an improved genetic algorithm. Materials and Methods: To calculate of detector positions for a source localizing RPM system optimization problem is defined. To solve the problem, a modified iterative genetic algorithm (MIGA) is developed. In general, a genetic algorithm (GA) finds a globally optimal solution with a high probability, but it is not perfect at all times. To increase the probability to find globally optimal solution rather, a MIGA is designed by supplementing the iteration, competition, and verification with GA. For an optimization problem that is defined to find detector positions that maximizes differences of detector signals, a localization method is derived by modifying the inverse radiation transport model, and realistic parameter information is suggested. Results and Discussion: To compare the MIGA and GA, both algorithms are implemented in a MATLAB environment. The performance of the GA and MIGA and that of the procedures supplemented in the MIGA are analyzed by computer simulations. The results show that the iteration, competition, and verification procedures help to search for globally optimal solutions. Further, the MIGA is more robust against falling into local minima and finds a more reliably optimal result than the GA. Conclusion: The positions of the detectors on an RPM for radioactive source localization are optimized using the MIGA. To increase the contrast of the measurements from each detector, a relationship between the source and the detectors is derived by modifying the inverse transport model. Realistic parameters are utilized for accurate simulations. Furthermore, the MIGA is developed to achieve a reliable solution. By utilizing results of this study, an RPM for radioactive source localization has been designed and will be fabricated soon.