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컴퓨터과학의 원리를 교육하기 위한 도구로서 언플러그드 교육은 널리 사용되고 있다. 본 연구에서는 초등학교에서 자연수를 이진체계로 표현하는 사전 학습이 이루어진 학생들을 대상으로 문자를 이진체계로 표현하는 교육자료 개발에 대해 제시하였다. 학습방법은 활동중심학습으로 구성하였으며, 학습내용은 생활 속의 문자를 이진체계로 표현하는 원리를 학습하기 위하여 문자를 수와 대응시킨 문자표를 사용하여 이진체계로 표현하기이다. 개발된 자료의 적합성 평가를 위하여 교육자료를 현장에 적용하였으며, 그 결과는 문자의 이진체계 표현에 대한 지식과 적용 및 확장은 효과적인 것으로 평가되었다.

Unplugged has been widely used as an instrument for teaching the basic principles of Computer Science. We’ll present ‘the binary system teaching contents for the characters' developed for the elementary. And they will successfullyguide the student to understand the characters using in computer system. The activity-based learning is provided for describing characters with coding and decoding rules, and the using will be found out in everyday life. To check the adequacy of these materials they were tested to the elementary classroom, and the results showed effectively at Knowledge, Attitude, Generalization levels.

컴퓨터과학의 원리를 교육하기 위한 도구로서 언플러그드 교육은 널리 사용되고 있다. 본 연구에서는 초등학교에서 이진법에 대한 사전학습이 이루어져 있지 않은 학생들을 대상으로 자연수를 이진체계로 표현하는 교육자료 개발에 대해 제시하였다. 사전학습 수준은 수를 세기, 수와 카드를 연결하기, 수를 배열하기가 요구된다. 학습방법은 활동중심학습으로 구성하였으며, 학습내용은 생활 속의 수를 컴퓨터에서 사용하는 방법을 이해하도록 자연수를 이진체계로 표현하기, 생활 속의 이진체계 찾아보기 등이다. 개발된 자료의 적합성 평가를 위하여교육내용 구성과 평가의 방법에 대하여 현장적용을 하였으며, 자연수의 이진체계 표현에 대한 지식과 태도, 일반화에 효과적인 것으로 평가되었다.

Unplugged has been widely used as an instrument for teaching the basic principles of Computer Science. This study presents the teaching contents developed for the children without any knowledge of binary numbers. which successfully guided them to understand the natural number binary system. The level of the pre-lesson for this learning requires counting numbers, matching numbers with cards, and arranging numbers. The activity-based learning is provided for describing natural numbers with the binary system and finding out them in everyday life. To check the adequacy of these materials on their organization and assessment they were tested at the classroom, which showed effective about the knowledge, the attitude and the generalization.

Background: A simple binary scoring system (SBSS) was developed and used to assess the welfare measures ofcommercial broiler chickens in South Korea. We also correlated welfare measures with environmental parameters ofbroiler house. Our measures of welfare included lameness, hock burn (HB) and foot pad dermatitis (FPD), whilstenvironmental parameters included air temperature, relative humidity, air speed, light intensity, air quality (inparticular carbon dioxide (CO2) and ammonia (NH3) concentrations) and airborne microbes. Results: The effect of environmental parameters on welfare measures was apparent even on 10-day-old broilers. Anon-parametric correlation analysis revealed significant correlations between environmental parameters and welfaremeasures. The key environmental parameters were relative humidity and light intensity. The results indicate thatthere is a need for proper control of environmental conditions on poultry farms, which could reduce health problemsand subsequently reduce disease and mortality. Conclusions: In conclusion, the simplicity of SBSS makes it preferable over more complex scoring systems and allowsa farmer to more easily assess the welfare measures on their own farm.

Recently, the magnitude of electronic data interchange (EDI) document processing for the handling of port logistics is abruptly being increased. The existing system processes EDI documents in a script mode, but due to a complicated script preparation procedure and low document processing efficiency, it cannot meet the demand as the usage flow of documents increases. In this paper, an EDI electronic document processing system was designed and implemented in a document scanner and mapper, which are binary form electronic document processing tools and do not require script files during the conversion of extensible markup language (XML)-based electronic documents. This new system has the merits of XML features during reading and writing with improved speed, usage convenience, and good portability on systems when compared to the conventional ones.

Resistive random-access memory (RRAM), one of the most potential candidates for synaptic devices, has been studied steadily for many years. However, destructive switching methods and process variations acted as factors that were difficult to apply to the neuromorphic system. In particular, the breakdown of switching layer may occur even before training is sufficiently performed if endurance is not secured in on-chip training. In this work, we propose a binary neural network of a hardware friendly learning algorithm to overcome this issue at system-level study. Binary neural network (BNN) can accelerate the time at which the recognition rate is saturated because all weight states are defined by one switching event. In addition, the resistance to variation can be improved by using the maximum/minimum of the current level of the memristors. However, the conventional BNN has the disadvantage that batch normalization and real value weights must be used together for learning. In this paper, we verified a method for learning BNN using boundary values.

Race Condition은 둘 이상의 프로세스가 하나의 공통 자원에 대해 입력이나 조작이 동시에 일어나 의도치 않은 결과를 가져오는 취약점이다. 해당 취약점은 서비스 거부 또는 권한 상승과 같은 문제를 초래할 수 있다. 소프트웨어에서 취약점이 발생하면 관련된 정보를 문서화하지만 종종 취약점의 발생 원인을 밝히지 않거나 소스코드를 공개하지 않는 경우가 있다. 이런 경우, 취약점을 탐지하기 위해서는 바이너리 레벨에서의 분석이 필요하다. 본 논문은 UNIX 커널기반 File System의 Time-Of-Check Time-Of-Use (TOCTOU) Race Condition 취약점을 바이너리 레벨에서 탐지하는 것을 목표로 한다. 지금까지 해당 취약점에 대해 정적/동적 분석 기법의 다양한 탐지 기법이 연구되었다. 기존의 정적 분석을 이용한 취약점 탐지 도구는 소스코드의 분석을 통해 탐지하며, 바이너리 레벨에서 수행한 연구는 현재 거의 전무하다. 본 논문은 바이너리 정적 분석 도구인 Binary Analysis Platform (BAP)를 통해 Control Flow Graph, Call Graph 기반의 File System의 TOCTOU Race Condition 탐지 방법을 제안한다.

Race Condition is a vulnerability in which two or more processes input or manipulate a common resource at the same time, resulting in unintended results. This vulnerability can lead to problems such as denial of service, elevation of privilege. When a vulnerability occurs in software, the relevant information is documented, but often the cause of the vulnerability or the source code is not disclosed. In this case, analysis at the binary level is necessary to detect the vulnerability. This paper aims to detect the Time-Of-Check Time-Of-Use (TOCTOU) Race Condition vulnerability of UNIX kernel-based File System at the binary level. So far, various detection techniques of static/dynamic analysis techniques have been studied for the vulnerability. Existing vulnerability detection tools using static analysis detect through source code analysis, and there are currently few studies conducted at the binary level. In this paper, we propose a method for detecting TOCTOU Race Condition in File System based on Control Flow Graph and Call Graph through Binary Analysis Platform (BAP), a binary static analysis tool.

가스하이드레이트(gas hydrate)는 물 분자(host)가 메탄, 에탄, 이산화탄소 같은 저분자가스(guest)와 고압, 저온의 평형상태에서 포접화합물을 형성하는 것으로 규명되어져 있다. 가스하이드레이트는 에너지 자원으로써의 활용 가치뿐만 아니라 그것의 물리화학적 특성을 이용한 여러 응용 기술 분야에 걸쳐 다양하게 활용되고 있는 실정이다. 분리공정 기술, 에너지 가스의 수송 및 저장 기술, 이산화탄소 격리 기술 등이 대표적인 응용기술이라고 할 수 있다. 특히 가스하이드레이트 냉동기 시스템은 기존의 냉각제로써 오존층 파괴의 주범으로 널리 알려진 CFC(chlorofluorocarbon)-형, HFC(hydrofluorocarbone)-형 냉각제들을 대체할 수 있는 친환경적인 냉각제로 이용될 것으로 기대되고 있다. 본 연구에서는 하이드레이트 냉동기 시스템에 적용하기 위해서 메탄과 이산화탄소를 이용한 다중객체 하이드레이트에 대한 상평형 및 포집률 변이 연구를 실시하였다. 새로 고안된 장치의 적합성을 테스트하기 위해서 268～285 K의 온도범위와 2.0～7.5 MPa의 압력범위에서 순수 메탄 하이드레이트에 대한 상평형 연구를 실시하였고 기존 문헌의 값과 비교하였다. 또한 methane + acetone, carbon dioxide + acetone, methane + tert-butyl methyl ether(TBME), carbon dioxide + TBME, and carbon dioxide + tetrahydrofuran의 3상 상평형 데이터를 측정하였고, 가스하이드레이트의 해리열을 계산하기 위해 van der Waals-Platteeuw 모델을 이용하여 포집률을 예측하였다.

Gas hydrate is formed by a physical reaction between relatively small guest molecules and host water molecules under high pressure and low temperature conditions. Gas hydrates have been used in a variety of industrial fields not only as a large energy resource but also as a target medium for various technologies using its physicochemical characteristics. There are a lot of practical applications such as separation processes, natural gas storage-transportation and carbon dioxide sequestration. In particular, the refrigeration system using properties of gas hydrate is expected to be environment-friendly coolants. It is a non-toxic and energy saving process which can be used to replace CFCs which are well known as a main reason of destroying the ozone layer. In this study, the phase equilibrium and cage occupancy of the multi-guest hydrate systems including methane and carbon dioxide are observed to investigate the applicability of gas hydrates to the refrigeration system. To test and prove the validity and reproducibility of a newly designed experimental apparatus, the dissociation pressures of pure methane hydrates are measured at the range of 268~285 K and 2.0~7.5 MPa and compared with the literature values. The three-phase equilibrium conditions of methane + acetone, carbon dioxide + acetone, methane + tert-butyl methyl ether (TBME), carbon dioxide + TBME, and carbon dioxide + tetrahydrofuran hydrates are measured over a wide range of temperatures and pressures. To obtain the heat of dissociation of gas hydrate, the cage occupancy of relatively small guests are estimated using the van der Waals-Platteeuw model.

This Study is carried out to stabilize the system according to the change of superheat and subcooling in binary refrigeration system by applying cascade system. When the system on 1 st stage was started and the system on the other side was operated, a temperature reversal phenomenon occurred in which the temperature of the 1 st cascade outlet was temporarily lowered. This means that the condensate heat exchange on the 2 nd is not good, which can cause the compressor to overheated. In order to maintain stable system operation, the opening degree of the expansion valve is controlled to increase the refrigerant circulation amount, thereby facilitating the condensation heat exchange on the 2 nd stage system. We have found that the most suitable refrigerant circulation amount is found by stabilizing the operation of the system while lowerning the super low temperature from -65℃ to -70℃ and increasing again to -60℃.

In this study, We aim to provide design data for a low-temperature refrigeration system to select operating conditions for predicting maximum performance of an eco-friendly binary refrigeration system based on changing operating conditions The operating variables considered in this paper are evaporating temperature, condensing temperature, superheating degree, subcooling degree, and compression efficiency. The main results are summarized as follows: In the low temperature range of -50℃ to -30℃, the COP of the system increased as the evaporating temperature and subcooling degree of the binary refrigeration system for R744-R717 increased, but the COP decreased as the condensing temperature and superheating degree increased. It was confirmed that factors such as superheating, subcooling, condensing temperature, evaporating temperature, cascade temperature difference, and compression efficiency affect the performance coefficient of the binary refrigeration cycle for R744 and R717, and it was found that each of these factors has a cascade evaporating temperature that maximizes the performance of the binary refrigeration cycle.

고등식물의 형질전환용 유전자운반체로써 가장 많이 사용되고 있는 Ti-plasmid를 이용해서 당근세포를 형질 전환시키기 위한 연구의 일환으로 Agrobacterium spp를 helper로 이용하여 NPT II gene를 함유하고 있는 binary vector GA472를 당근세포에 삽입시켜 kanamycin에 대해 저항성을 나타내는 세포주를 선발하고자 본 연구를 수행하였다. 국내 토양에서 선발한 A.tumefaciens 2종과 disarmes된 PC2760 그리고 hypervirulent균주인 A281에 tri-parental mating 방법에 의해서 binary vector인 pGA472을 도입하여 transconjungants인 A. tumefaciens c-23-1/pGA472,K29-1/pGA472, PC2760/PGA472 그리고 A281/pGA472를 획득하였다. Transconjungants는 plasmid의 분리, 정제방법에 의해서 추출한 후 0.7% agarose gel 상에서 관찰해 본 결과 4균주 공히 NTPII gene이 삽입된 pGA472와 Ti-plasmid를 함유하고 있는 것을 확인 하였다. 확인된 conjugant와 당근정상조직을 동시배양방법에 의해서 형질전환을 유도한 후 정상조직은 전혀 생존이 되지않은 kanamycin에 대해서 저항을 나타내는 callus를 선발할 수 있었다.

These studies were carried out to obtain the transformant from carrot cells by using binary vector pGA472 with NPT II gene to confer kanamycin resistance in the plant cells. The binary vector pGA472 was mobilized from E. coli MC1000 into A. tumefaciens strains isolated in the Korea, C23-1. K29-1, and disarmed Ti-plasmid PC2760, and A28l using a tri-parental mating method with E. coli HB101/pRK2013. Transconjugants, C23-1/pGA472, K29-1/pGA472, PC2 760/pGA472 and A28l/pGA472 were obtaind on the minimum AB media containing tetracycline and kanamycin, were comfirmed to hold the Ti-plasmid and pGA472 binary vector on the 0.7% agarose gel. Transformed carrot calli were initiated on the MS media supplemented with l00/ml kanamycin and 250ug/ml carbenicillin after co-cultivation of carrot explant and transconjugant Agrobacteria. Selected callus was grown vigouousley for subculture on the medium containing 100/ugml kanamycin, thus indication that the selected callus was transformed with NPT II gene.

In cloud storage system, when we search similar documentation files, keyword-based similarity evaluation scheme is well performed. However, if we want to find similar binary files then it is very difficult to satisfy user request. Because there is no widely used binary file search system that supports similarity evaluation among files. File similarity evaluation is essential for digital forensic and data deduplication field. In the file similarity processing time, the CPU consumption and resource overhead of memory are increased as the number of files increase. Moreover, as the file size is getting bigger, the overhead of metadata management is critical. In this paper, we suggest the similarity evaluation scheme using a hybrid chunking which reduce overall processing time of similarity evaluation. Experiment result shows that the proposed system can reduce processing time and data storage capacity effectively.

In power systems operation, state estimation takes an important role in security control. For the state estimation problem, the weighted least squares (WLS) method and the fast decoupled method have been widely used at present. Especially when bad data are mutually interacting, the detecting of multiple bad data may be difficult to handle, since the normalized or weighted residuals may become faulty. Then the problem of detecting bad data is considered as a combinatorial decision procedure. In this paper, the binary Particle Swarm Optimization (PSO) is used for the detecting of multiple bad data in the power system state estimation. The PSO, like other meta-heuristic algorithms, can handle constrains that would be troublesome in classical mathematical approach. However, population based algorithms require higher computing time to find optimal point. This shortcoming is overcome by a parallel processing of PSO algorithm. The parallel PSO algorithm is implemented on a PC cluster system with 8 personal computers. The proposed approach has been tested on the IEEE-14 and 118 bus systems. The results showed that the binary PSO based procedures behave satisfactorily in the detecting multiple bad data and computing time of parallelized PSO algorithm can be reduced without losing the quality of solution.

The important indicators of multichannel ultrasonic ranging system are correlation characteristics and energy efficiency. The excitation sequences with good correlation characteristics can help avoid crosstalk among multichannel ultrasonic sensors. High energy efficiency can enhance measurement range. This paper proposes a crosstalk elimination method by using the optimal binary excitation sequences modulated with chaotic codes, which include chaotic binary amplitude shift keying (c-BASK), chaotic binary phase shift keying (c-BPSK) and chaotic binary frequency shift keying (c-BFSK). To obtain the both best correlation characteristics and energy efficiency, the Non-dominated Sorting Genetic Algorithm-II (NSGA-II) is applied to optimize the chaotic binary excitation sequences. Real experiments have been conducted using an ultrasonic ranging system that consists of eight-channel SensComp 600 series instrument-grade electrostatic sensors excited with chaotic binary modulation sequences. The experimental results show that the c-BFSK outperforms the c-BASK and c-BPSK in terms of the correlation characteristics and energy efficiency. With 2 ms c-BFSK excitation sequences, the longest measurable distance was 720 cm (i.e., increased 11% and 27% with c-BPSK and c-BASK, respectively) with maximal relative error 2.4%.

오늘날 유비쿼터스 사회에서 안전과 보안에 대한 관심은 점차 증대되고 있으며 이에 따라 무선을 기반으로 각종 인프라와 서비스가 증가하고 있다. 본 논문에서는 이러한 시대적 요구에 부응하기 위해서 국내 순수 개발 기술인 Binary CDMA를 소개하면서 이를 기반으로한 A/V 감시시스템을 제안한다. 무선 A/V 감시시스템은 무선 단말장치, 멀티채널 처리장치, A/V 관리서버로 구성되었으며 구현 방법과 무선환경 시험을 검증하므로써 장차 활용 범위를 넓힐 수 있는 가능성을 제시한다.

In ubiquitous society, there have been increasing demands on safety and security issues with infrastructures and services based on wireless technology. In this paper, we first introduce our own developed technology Binary CDMA to meet those demands. Then we present a wireless A/V surveillance system based on the Binary CDMA technology. The implemented wireless A/V surveillance system is composed of wireless terminals, wireless multiple channel processors, and an A/V management server, and the system gives a hint that the Binary CDMA technology can be adopted in practical ubiquitous systems to handle safety and security issues.

기존의 DS-CDMA 방식은 잡음이 많거나 채널 왜곡이 심한 환경에서는 성능이 급속히 저하하는 현상이 나타난다. 이러한 문제점 해결을 위한 다양한 연구들이 현재 진행되고 있으며, 본 논문에서도 이에 대한 해결방안을 제시한다. Chirp 방식은 레이더와 같은 변복조 방식에 다양하게 사용되고 있으며, 원하는 주파수 대역으로 쉽게 이동할 수 있고. 구현이 용이하다는 장점이 있다. 본 논문에서는 다중 접속이 가능한 DS-CDMA 기술과 chirp 변복조 기술을 결합한 Binary Chirp DS-CDMA(BCDS-CDMA) 방식을 제안한다. 제안한 DS-CDMA 시스템 성능을 평가하기 위하여, 가우시안 환경에서 기존의 DS-CDMA 방식과 비교 실험을 하였으며, 실험 결과 chirp을 이용한 방식이 DS-CDMA 보다 개선된 성능을 지니고 있음을 알 수 있었다.

The standard stellar models for HIP 20916 and HIP 101769 have been constructed to determine the properties of the binary system. Augmented with speckle data which is the magnitude difference between stars of the binary system, the previously determined parameters, such as [Fe/H], distance, total mass, and etc, are used to construct the standard stellar models. And the Green table is used to convert L and $T_{eff}$ into $M_v$ and color for comparison between models and observational data. We present the constructed stellar models of the system.