IoT 기반 간헐적 이벤트 로깅 응용에 최적화된 효율적 플래시 메모리 전력 소모 감소기법

권지수,조정훈,박대진 대한임베디드공학회 2019 대한임베디드공학회논문지 Vol.14 No.2

Low power issue is one of the most critical problems in the Internet of Things (IoT), which are powered by battery. To solve this problem, various approaches have been presented so far. In this paper, we propose a method to reduce the power consumption by reducing the numbers of accesses into the flash memory consuming a large amount of power for on-chip software execution. Our approach is based on using cooperative logging structure to distribute the sampling overhead in single sensor node to adjacent nodes in case of rare-event applications. The proposed algorithm to identify event occurrence is newly introduced with negative feedback method by observing difference between past data and recent data coming from the sensor. When an event with need of flash access is determined, the proposed approach only allows access to write the sampled data in flash memory. The proposed event detection algorithm (EDA) result in 30% reduction of power consumption compared to the conventional flash write scheme for all cases of event. The sampled data from the sensor is first traced into the random access memory (RAM), and write access to the flash memory is delayed until the page buffer of the on-chip flash memory controller in the micro controller unit (MCU) is full of the numbers of the traced data, thereby reducing the frequency of accessing flash memory. This technique additionally reduces power consumption by 40% compared to flash-write all data. By sharing the sampling information via LoRa channel, the overhead in sampling data is distributed, to reduce the sampling load on each node, so that the 66% reduction of total power consumption is achieved in several IoT edge nodes by removing the sampling operation of duplicated data.

성남지역 학교 영양(교)사와 학부모의 친환경농산물에 대한 인지도

권지수,조우균 대한지역사회영양학회 2019 대한지역사회영양학회지 Vol.24 No.4

Objectives: This study examined the nutrition teachers’ and parents’ recognition of environmentally-friendly agricultural products (EAPs) used in school foodservice. Methods: A questionnaire survey was given to 128 school foodservice nutrition teachers in Seongnam and 189 parents from Oct. 16 to Oct. 31, 2018 at Seongnam in Gyeonggi province. The survey included information on the recognition, satisfaction, and improvement of EAPs, and the results of the two groups were compared. Results: A comparison of the recognition of EAPs showed that nutrition teachers knew more about the EAPs and local government support in school foodservice than the parents. On the other hand, the parents were more aware than the nutrition teachers in that children have a higher affinity for EAPs than for general agricultural products in the school foodservice. A comparison of the level of satisfaction with the EAPs by nutrition teachers and parents revealed the nutrition teachers to be significantly more satisfied than parents in terms of the color, taste and nutrition of EAPs. Among the items that should be provided with EAPs, more than 50% of each group of nutrition teachers and parents answered that vegetables must be provided first. Some 70.9% of nutrition teachers and 84.5% of parents were aware of the certification standards of EAPs. The nutrition teachers had showed a slightly higher score than the parents in the certification system (3.51 vs. 3.25). In terms of improving the EAPs, 36.2% of nutrition teachers answered a reasonable price preferentially, whereas 56.4% of parents answered maintaining quality. In the expected effects of using EAPs, 57.9% of nutrition teachers answered an improvement of parents’ satisfaction on the school foodservice. On the other hand, 38.0% of parents answered an improvement of children’ satisfaction on school foodservice. Conclusions: Nutrition teachers and parents need to be educated on the certification systems that would enhance the trust in EAPs.

Effect of functional groups on SiO₂ with different calcination temperature on the prepared Pd/SiO₂ catalysts

권지수,김지선,이학성,이만식 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.1

The SiO₂ is widely used as catalyst supports, because of its high surface area and thermal stability. There are many functional groups on the silica surface. The Silanol group(Si-OH) hinders metal reduction. Because it leads to strong metal oxide-support interaction. The silanol groups are removed by thermal treatment, and this removal results in improvement of the metal dispersion. So we calcined the SiO₂ at 300°C to 1100°C. The Pd/SiO₂ is prepared by ion exchange method. From the FT-IR results, the amount of Si-OH was decreased with increasing as calcination temperature. And more than 700°C, Si-OH was disappeared completely. The results of CO-chemisorption indicated that the thermaltreatment(900°C) of SiO₂ lead to the highest dispersion of Pd as 7.97%. Therefore, to improve the metal dispersion of Pd/SiO₂, the interaction between Pd and silanol should be reduced. The enhancement in the hydrophobicity of the calcined SiO₂ supports would be increasing the metal dispersion.

1P-652 Synthesis of Pd/SiO₂ catalyst with different preparation methods and Pd precursors

권지수,백재호,이학성,이만식 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.1

Palladium catalyst is widely used for chemical process. but Palladium has high cost and finite resource as noble metal. therefore Palladium need to be deposited on supports which have high specific surface area and stability such as silica and alumina. the metal dispersion, which is crucial factor for catalytic activity, is closely related to interaction with supports. and this interaction can be controlled by preparation method and Pd precursor. in this study, Pd/SiO₂ catalysts are prepared by ion exchange and impregnation method. also it is used different Pd precursors, (NH₃)₄Pd(NO₃)₂ and H₂PdCl₄. Pd/SiO₂ prepared by H₂PdCl₄ has smaller Pd particle size than (NH₃)₄Pd(NO₃)₂. Ion exchange method lead to heavy aggregation of Palladium particle which have a negative influence for catalytic activity. in the conclusion, the Pd/SiO2 prepared by impregnation method and H₂PdCl₄ precursor has the smallest Pd particle size and highst catalytic activity.

Comparison of the Commercial QuantiFERON-CMV and Overlapping Peptide-based ELISPOT Assays for Predicting CMV Infection in Kidney Transplant Recipients

권지수,김태은,김선미,성흥섭,신성,김영훈,신의철,김성한,한덕종 대한면역학회 2017 Immune Network Vol.17 No.5

Cytomegalovirus (CMV) is one of the most important opportunistic infections in transplant recipients. Tests for CMV-specific T cell responses have been proposed to change the current risk stratification strategy using CMV assays. We evaluated the usefulness of pre-transplant CMV-specific T cell assays in kidney transplant (KT) candidates for predicting the development of CMV infection after transplantation comparing the results of the overlapping peptides (OLPs)-based enzyme-linked immunospot (ELISPOT) assay and the commercial QuantiFERON-CMV assay. We prospectively enrolled all cases of KT over a 5-month period, except donor CMV-seropositive and recipient seronegative transplants that are at highest risk of CMV infection. All the patients underwent QuantiFERON-CMV, CMV OLPs-based pp65, and immediate-early 1 (IE-1)-specific ELISPOT assays before transplantation. The primary outcome was the incidence of CMV infection at 6 months after transplant. The total of 47 KT recipients consisted of 45 living-donor KTs and 2 deceased-donor KTs. There was no association between positive QuantiFERON-CMV results and CMV infection. However, 10 of 34 patients with phosphoprotein 65 (pp65)- or IE-1-specific ELISPOT results higher than cut-off value developed CMV infections compared with none of 13 patients with results lower than cut-off value developed CMV. The OLPs-based ELISPOT assays are more useful than the QuantiFERON-CMV assay for predicting CMV infection. Patients with higher CMV-specific T cell immunity at baseline appear to be more likely to develop CMV infections after KT, suggesting that the abrupt decline in CMV-specific T cell responses after immunosuppression, or high CMV-specific T cell responses due to frequent CMV activation before KT, may promote CMV infection.

GPU 기반 임베디드 시스템에서 대용량 데이터의 안정적 수신을 위한 ECC 연산의 가속화

권지수,박대진,Kwon, Jisu,Park, Daejin 한국정보통신학회 2020 한국정보통신학회논문지 Vol.24 No.7

최근 임베디드 시스템에서 사용되는 데이터의 크기가 증가함에 따라, 대용량의 데이터를 안전하게 수신하기 위한 ECC (Error Correction Code) 복호화 연산의 필요성이 강조되고 있다. 본 논문에서는 GPU가 내장된 임베디드 시스템에서 해밍 코드를 사용하여 ECC 복호화를 할 때, 신드롬 벡터를 계산하는 연산의 수행을 가속할 방법을 제안한다. 제안하는 가속화 방법은, 복호화 연산의 행렬-벡터 곱셈이 희소 행렬을 나타내는 자료 구조 중 하나인 CSR (Compressed Sparse Row) 형식을 사용하고, GPU의 CUDA 커널에서 병렬적으로 수행되도록 한다. 본 논문에서는 GPU가 내장된 실제 임베디드 보드를 사용하여 제안하는 방법을 검증하였고, 결과는 GPU 기반으로 가속된 ECC 복호화 연산이 CPU만을 사용한 경우에 비하여 수행 시간이 감소하는 것을 보여준다. Recently, as the size of data used in an embedded system increases, the need for an ECC decoding operation to robustly receive a massive data is emphasized. In this paper, we propose a method to accelerate the execution of computations that derive syndrome vectors when ECC decoding is performed using Hamming code in an embedded system with a built-in GPU. The proposed acceleration method uses the matrix-vector multiplication of the decoding operation using the CSR format, one of the data structures representing sparse matrix, and is performed in parallel in the CUDA kernel of the GPU. We evaluated the proposed method using a target embedded board with a GPU, and the result shows that the execution time is reduced when ECC decoding operation accelerated based on the GPU than used only CPU.

Methyl oleate와 Maleic anhydride의 말레인화 반응을 통한 절삭유 첨가제 합성

권지수,백재호,김경호,문부현,이학성,이만식 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.0

오늘날에는 금속가공의 특성에 따라 많은 종류의 절삭유가 제조되고 있고 각종 첨가제가 사용되고 있다. 특히 절삭유의 품질은 첨가제의 종류에 따라 크게 좌우된다. 그러나 현재 첨가제의 대부분은 수입에 의존하고 있고, 국내 첨가제 제조업체 제품의 한정성으로 윤활유, 절삭유의 품질의 한계가 있는 상황이다. 본 연구에서는 유화안정성 및 안정화제 역할을 함과 동시에 폐기 시 쉽게 분해 될 수 있는 생분해성 복합기능성 첨가제 합성을 진행하였다. 본 반응은 methyl oleate와 maleic anhydride의 말레인화반응인 1차 반응과 maleinization methyl oleate와 n-butanol의 ester반응의 2차 반응으로 진행되었다. 이때 촉매의 사용유무와 반응조건에 따른 수율 및 반응 진행도를 확인하였다.

차량용 임베디드 프로세서에서 저전력 반응적 제어를 위한 이기종 멀티코어 협력적 스트리밍 온-칩 소프트웨어 구조

권지수,박대진 대한임베디드공학회 2022 대한임베디드공학회논문지 Vol.17 No.6

This paper proposes a multi-core cooperative computing structure considering the heterogeneous features of automotive embedded on-chip software. The automotive embedded software has the heterogeneous execution flow properties for various hardware drives. Software developed with a homogeneous execution flow without considering these properties will incur inefficient overhead due to core latency and load. The proposed method was evaluated on an target board on which a automotive MCU (micro-controller unit) with built-in multi-cores was mounted. We demonstrate an overhead reduction when software including common embedded system tasks, such as ADC sampling, DSP operations, and communication interfaces, are implemented in a heterogeneous execution flow. When we used the proposed method, embedded software was able to take advantage of idle states that occur between heterogeneous tasks to make efficient use of the resources on the board. As a result of the experiments, the power consumption of the board decreased by 42.11% compared to the baseline. Furthermore, the time required to process the same amount of sampling data was reduced by 27.09%. Experimental results validate the efficiency of the proposed multi-core cooperative heterogeneous embedded software execution technique.

고추 역병 저항성 후보 유전자 삽입을 통한 담배(Nicotiana benthamiana) 형질전환체 개발 최적화

권지수,염지은,강원희 경상국립대학교 농업생명과학연구원 2023 농업생명과학연구 Vol.57 No.1

Phytophthora capsici (P. capsici) is a soil-borne fungal that causing Phytophthora blight with the significant problem to chili pepperfarming in wide-spread globally. To date, the resistance of P. capsici regulated by several minor quantitative trait loci (QTLs) a consistentmajor QTL on chromosome 5. The study is more needed such as the selection of candidate genes and identification of their function. Especially, the Capsicum annuum is difficult to transformation, and there are many limitations in identifying resistance genes throughinteraction studies with pathogens. Hence, Nicotiana benthamiana (N. benthamiana), a Solanaceae crop such as chili pepper, is knownas a pathogen interaction model source and is useful for identifying the function of resistance genes through transformation. In thisstudy, an investigation of the resistance mechanism to P. capsici, a plant resistance gene analog (RGA) was selected, and optimizationof N. benthamiana transformation technique was performed on these genes. The CaNBARC105 and CaNBARC112 were identified asRGA candidates through analysis of the known P. capsici resistance molecular markers on chromosome 5 in pepper. We developed a N. benthamiana transformation into which chili pepper RGA was inserted based on the Agrobacterium tumefaciens for these two genesand we confirmed through genomic PCR and RT-PCR using gene-specific sequence. Also, it was verified phenotypes that this transformedN. benthamiana was no effect on its growth and development. This transformed N. bentahmiana will be helpful as a basis for theidentification of the Phytophthora blight resistance gene and mechanistic research in chili pepper. 고추역병균(Phytophthora capsici)은 고추 생육 전반에 걸쳐 병을 발생시켜 농가 소득에 큰 손실을 일으키고 있다. 고추 역병균 저항성은 양적형질 유전자좌(Quantitative Trait Loci, QTL)에 의해 조절되며 주동 유전자는 고추의 5번 염색체에 존재한다고 보고 되었지만, 후보 유전자의선발 및 저항성 유전자 규명 연구는 아직 초기 단계이다. 특히, 고추는 형질전환이 어려운 작물로써 병원균과의 상호작용 연구를 통한 저항성유전자 동정에 제한이 많다. 반면 고추와 같은 가지과 작물인 담배(Nicotiana benthamiana)는 병원균 상호작용 모델로 알려져 형질전환을 통해저항성 유전자 규명에 활용된다. 본 연구에서는 고추 역병 저항성 기작 규명을 위한 기초 연구로써, 식물 저항성 유사 유전자(Resistance GeneAnalog, RGA)를 선발하고, 이들 유전자들에 대한 담배 형질전환 기법 최적화 연구를 수행하였다. 고추 5번 염색체에 존재하는 고추 역병 저항성분자표지들을 분석하여 RGA 후보 유전자인 CaNBARC105, CaNBARC112 유전자를 동정하였다. 이들 유전자들에 대해 Agrobacteriumtumefaciens를 매개체로 하여 고추 RGA가 삽입된 담배 형질전환체를 개발하였다. 형질전환 여부는 유전자 특이적인 서열을 이용한 genomicPCR과 RT-PCR 검증을 통해 이들 형질전환 된 담배들의 생육 및 발달에 영향이 없다는 것을 확인하였다. 본 연구는 향후 고추 병 저항성 후보유전자들이 삽입된 담배 형질전환체는 고추 역병 저항성 유전자 규명 및 기작 연구에 기반이 될 것이다

차량의 데이터 처리 오버헤드를 줄이기 위한 이동 속도와 거리 추정 기반의 센싱 데이터 수집 주기 제어 기법

권지수,박대진,Kwon, Jisu,Park, Daejin 한국정보통신학회 2020 한국정보통신학회논문지 Vol.24 No.12

주변 환경으로부터 직접 데이터를 수집하는 센서 노드는 많은 제약 조건을 가지기 때문에 자원의 효율적인 사용이 필요하다. 본 논문에서는 도로를 주행 중인 차량의 위치 데이터를 수신하는 센서 노드에서, 칼만 필터로 추정한 대상의 속도와 이동 거리 가중치로 데이터 수신 주기를 변경한다. 차량의 속도가 느릴수록 센서 노드의 데이터 수신 주기를 길게 함으로써 전체 네트워크에서 이루어지는 연산 시간을 줄일 수 있다. 제안하는 기법은 MATLAB으로 구현된 교통 시뮬레이터를 통하여 검증하였으며, 기존 방법에 비해 제안하는 기법을 사용하는 센서 네트워크에서 연산에 소요되는 시간이 감소하는 것을 확인하였다. Sensor nodes that directly collect data from the surrounding environment have many constraints, such as power supply and memory size, thus efficient use of resources is required. In this paper, in a sensor node that receives location data of a vehicle on a lane, the data reception period is changed by the target's speed estimated by the Kalman filter and distance weight. For a slower speed of the vehicle, the longer data reception interval of the sensor node can reduce the processing time performed in the entire sensor network. The proposed method was verified through a traffic simulator implemented as MATLAB, and the results achieved that the processing time was reduced in the entire sensor network using the proposed method compared to the baseline method that receives all data from the vehicle.