• 디지털융복합연구
• /
• 제20권4호
• /
• pp.397-404
• /
• 2022

최근 산업 분야에서는 생산 효율성 향상 및 비용 절감을 위해서 저전력 프로세스와 네트워크 카드를 결합한 IIoT 장치를 산업 현장에 융합시킨 다양한 연구를 진행하고 있다. 본 논문에서는 산업 현장에 구축된 기반 시설에 IIoT 센서 정보를 부착하여 생산된 제품을 효율적으로 관리할 수 있는 처리 모델을 제안한다. 제안 모델은 IIoT에서 생산된 제품의 센싱 정보를 일정 간격으로 체크하여 비정상적으로 처리된 센싱 정보를 실시간으로 탐지하도록 생산 제품에 IIoT 데이터 수집, 전처리, 특성 생성 및 레이블을 사용하여 생산 데이터를 만든다. 특히, 제안 모델은 산업 현장에서 생산되는 제품 정보를 실시간으로 처리할 수 있도록 추적 및 모니터링을 수행하여 관리자가 손쉽게 IIoT 데이터를 손쉽게 처리할 수 있다. 또한, 기존 생산 환경을 기반으로 제안 모델을 운용하기 때문에 기존 시스템과의 연계가 원활하다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제16권2호
• /
• pp.445-466
• /
• 2022

As everything linking to the internet, people can subscribe to various services from a service provider to facilitate their lives through the Internet of Things (IoT). An obligatory thing for the service provider is that they should push the service data safely and timely to multiple IoT terminal devices regularly after the IoT devices accomplishing the service subscription. In order to control the service message received by the legal devices as while as keep the confidentiality of the data, the public key encryption algorithm is utilized. While the existing public encryption algorithms for push service are too complicated for IoT devices, and almost of the current subscription schemes based on push mode are relying on centralized organization which may suffer from centralized entity corruption or single point of failure. To address these issues, we design a secure subscription-push service scheme based on blockchain and edge computing in this article, which is decentralized with secure architecture for the subscription and push of service. Furthermore, inspired by broadcast encryption and multicast encryption, a new encryption algorithm is designed to manage the permissions of IoT devices together with smart contract, and to protect the confidentiality of push messages, which is suitable for IoT devices. The edge computing nodes, in the new system architecture, maintain the blockchain to ensure the impartiality and traceability of service subscriptions and push messages, meanwhile undertake some calculations for IoT devices with limited computing power. The legalities of subscription services are guaranteed by verifying subscription tags on the smart contract. Lastly, the analysis indicates that the scheme is reliable, and the proposed encryption algorithm is safe and efficient.

• 분석과학
• /
• 제35권2호
• /
• pp.69-81
• /
• 2022

The method of measuring and classifying the energy category of neutrons directly using raw data acquired through a CZT detector is not satisfactory, in terms of accuracy and efficiency, because of its poor energy resolution and low measurement efficiency. Moreover, this method of measuring and analyzing the characteristics of low-energy or low-activity gamma-ray sources might be not accurate and efficient in the case of neutrons because of various factors, such as the noise of the CZT detector itself and the influence of environmental radiation. We have therefore developed an efficient method of analyzing radiation characteristics using a neutron and gamma-ray analysis algorithm for the rapid and clear identification of the type, energy, and radioactivity of gamma-ray sources as well as the detection and classification of the energy category (fast or thermal neutrons) of neutron sources, employing raw data acquired through a CZT detector. The neutron analysis algorithm is based on the fact that in the energy-spectrum channel of 558.6 keV emitted in the nuclear reaction ¹¹³Cd + ¹n → ¹¹⁴Cd + in the CZT detector, there is a notable difference in detection information between a CZT detector without a PE modulator and a CZT detector with a PE modulator, but there is no significant difference between the two detectors in other energy-spectrum channels. In addition, the gamma-ray analysis algorithm uses the difference in the detection information of the CZT detector between the unique characteristic energy-spectrum channel of a gamma-ray source and other channels. This efficient method of analyzing radiation characteristics is expected to be useful for the rapid radiation detection and accurate information collection on radiation sources, which are required to minimize radiation damage and manage accidents in national disaster situations, such as large-scale radioactivity leak accidents at nuclear power plants or nuclear material handling facilities.

• 무역상무연구
• /
• 제39권
• /
• pp.143-175
• /
• 2008

The documentary letter of credit is the most preferred and frequently used method in International Payment System in Korea, as it has less possibility of occurring credit risks in export than any other payment system. That's because the exporter can get payment from the issuing bank(confirming bank) by delivering the goods and presenting documents following the required procedure under the letter of credit, as the payment is affirmed by the issuing bank(including the confirming bank in case of the confirmed letter of credit) regardless of the buyer's payment. However, the pattern of payment methods used in international trade of Korea is changing dramatically like the importance of the credit is decreasing continuously among the payment methods while the remittance is increasing. The increase of remittance has a positive aspect that International Payment System are changing into those of advanced countries, but the decrease of the credit also has a negative aspect that the exporter might have a greater credit risks. Therefore, we need a systematic device to deal with this. Exporters in Korea usually have used the export credit insurance to deal with the credit risks However, the export credit insurance also have a limitation as the policy finance due to the limitation based on the credit status of the business and the limitation of acceptance from the lack of financial resources of the government, etc. Korea, which is the 11th export power in the world, has a basic limitation to deal with the credit risks by depending on the export credit insurance only. So, in this thesis, I have studied on the international factoring, forfaiting, which are advanced export finances and widely used in advanced countries, as substitutes to deal with the credit risks. the international factoring is an trade financing in which a factor offers full services such as credit cover, offering prepayment, collection, account receivables, management, etc, instead of the exporter on the account receivables occurred by the exporter's delivering goods to the importer. This international factoring has a high possibility of using as a means to deal with the credit risks, because it offers prepayment without recourse. the forfaiting is another export financing in which a forfaiter purchases the draft, the promissory note and other negotiable instruments issued from the international trade, with fixed interest rate without recourse from the exporter or previous holder. By using this method, they can avoid foreign exchange risks, contingency risks as well as credit risks, as the conveyances like the promissory note, etc are issued with the note warranty so-called 'per aval' in business practice. These trade financing are good substitutes to deal with the credit risks in export, but they are not widely used in Korea. Though it can be explained with various reasons, the common reasons are the lack of understanding on the use of advanced export finance, the lack of experts to manage the advanced trade finance, the conservative way of thinking of domestic organizations related to trade financing, the lack of organizations supporting the trade financing, etc.

• 한국산학기술학회논문지
• /
• 제9권5호
• /
• pp.1154-1163
• /
• 2008

배전자동화시스템(DAS:Distribution Automation System)과 변전자동화시스템(SCADA:Supervisory Control And Data Acquisition)은 전력계통을 컴퓨터와 통신기술을 이용하여 운용하는 주된 시스템으로, 현재 독립적으로 운영됨으로 인해 신속하게 처리되어야 하는 고장처리 및 활선작업처리가 지연되는 등의 문제점이 제기되어왔고, 이에 따라 DAS-SCADA 연계 연구가 요구되었다. 연계방법으로 직접연계, 웹연계, DAS 기능부 전력량계를 이용한 연계가 2005년 11월부터 2007년 12월까지 한전 사업소에서 시범 운영되었고, 그 결과 투자비용 면에서 직접연계방법이 웹연계 방법에 비해 약 1.3배 높지만 다양한 변전소 운전정보 전달의 신속성, 제어기능 우수 등의 타당성이 입증됨으로써 직접연계방법에 의한 DAS-SCADA 연계가 2010년까지 한전 사업소에 전국적으로 확대 적용될 계획이다. 시범 운영시 제기된 문제점을 개선하기 위해 변전소 개체별 통신 방법을 이용한 데이터 연계방안으로 개선하여 연계DB 자동구축 기능 및 연계시스템 진단/Log 기능을 개발하였다. 연계데이터 포인트와 통신데이터 종류를 정의하고, SCADA HMI 프로그램을 개발하여 변전소 단선도 자동생성 기능, 변전소 단선도 수동편집 기능, SCADA 감시 제어기능 및 이력관리 기능을 개발하였다. DAS-SCADA 연계시 정전건당 평균시간을 약 33% 단축하여 전력공급 신뢰도를 향상하고, 배전 계통운영센터와 변전소간 활선작업 처리절차 축소로 전력계통 효율적 운영에 기여하고, 나아가 고장시 부하절체 자동처리로 완전한 배전자동화 실현 및 해외 수출화 사업에도 크게 기여할 것으로 기대된다.

• 한국융합학회논문지
• /
• 제12권8호
• /
• pp.31-37
• /
• 2021

산업의 발전으로 도시화로 인해 건물의 규모가 커지면서, 건물의 공기 정화 및 쾌적한 실내 환경을 유지의 필요성 또한 증가하고 있다. 냉동 시스템의 모니터링 기술의 발전으로 건물 내에 발생하는 전력 소모량을 관리할 수 있게 되었다. 특히 상업용 건물에서 발생하는 전력 소모량 중 약 40%가 냉동 시스템에서 일어난다. 따라서 본 연구 냉동시스템 고장진단 알고리즘을 개발하기 위해서 냉동시스템의 구조를 이해하고, 냉동 시스템의 운영과정에서 발생하는 데이터를 수집 분석하여 다양한 유형과 심각도를 가지는 고장 상황을 조기에 신속하게 탐지 분류하고자 하였다. 특히 분류가 어려운 고장 유형들의 분류 정확도를 향상시키기 위하여 3단계 진단 및 분류 알고리즘을 개발하여 제안하였다. 다수의 실험과 초모수 (hyper parameter) 최적화 과정을 거쳐 각 단계에 적합한 분류 모형으로 SVM과 LGBM에 기반 한 모형을 제시하였다. 본 연구에서는 고장에 영향을 미치는 특성을 최대한 보존하면서, 선행연구에서 어려움을 겪었던 냉매 관련 고장을 포함한 모든 고장 유형을 우수한 결과로 도출하였다.

• 대한예방한의학회지
• /
• 제4권1호
• /
• pp.32-50
• /
• 2000

On the process of research in the plan on oriental medical participation in the industrial health sponsored by BK21 project, we carried out the oriental medical health examination program for workers during former half-year We reached the conclusion as follows, 1. The oriental medical health examination program is contents and formalities that should be determined by present industrial health system, based on the oriental medical system and scholastic character, and included probability of the western and oriental medical cooperation. 2. The oriental medical health examination program can promote capability of individual health management and productive power of workers, and it is capable to manage on the self-conscious symptoms and macroschophically approach to their environment 3. The oriental medical health examination program that we have developed, is flow as questionare, understanding of working environment, information of result and later management. It is composed of three fields as follow , first, use of pulse diagnostic apparatus, understanding of the health promotion life style, and diagnosis of the oriental medical doctor, second, analysis of constitution, third, photographing for understanding of the musculoskeletal disorders, questionare for musculoskeletal self-conscious symptoms, and diagnosis of oriental medical doctor. 4. The oriental medical health examination program that we have developed, progressive from the view point of health, makes the oriental medical doctor's roll more important. It is the first trial at the western and oriental medical cooperation and characterized by excellence about musouloskeletal disorders. But it need to be improved in aspects of time and specialist on the health examination, diagnostic apparatus, control of examinant and later management. So we think that it needs research on the employment of health examination specialist, establishment of later management system, development of significantly diagnosable standard and assessable form on the health examination, and contents of health examination on the western and oriental medical cooperation.

• 대한가정학회지
• /
• 제43권1호
• /
• pp.145-165
• /
• 2005

In 1937, most Korean compatriot who lived in Yunhaeju moved to Kazakhstan and Uzbekistan in Central Asia following the deportation policy of Russia. Korean compatriot have kept their traditional life style for 140 years, without a deep relationship with Korea. This study examined the heating systems of Korean compatriot in Yunhaeju, Kazakhstan and Uzbekistan, Russia. A literature review and field research, based on Ethnography as a research method, was employed. The results of the research were as following: 1) Korean compatriot in Yunhaeju use a Pechika, which is a radiator that uses hot water, and a Gudul as the main heating systems, but the use of a Pechika was most common. A Pechika functions for cooking as well as for warming the house. The room with the Gudul was connected to the kitchen, so this space was used as a place for cooking and eating, for family members to meet. Many kinds of fuel, like gas and electricity, were used to power the heating systems. 2) Korean compatriot in Kazakhstan use radiators, with hot water as the main heating system, with ratio using Gudul used in this region being the highest of all the three areas. The most common fuels used for a Gudul were wood and coal, and gas was also used in cooking. The room with the Gudul was planned to be located beside the fireplace, without any walls. The people using a Gudul use that place for eating and meeting, as well as for family members to sleep. 3) The main heating system of Korean compatriot in Uzbekistan was a radiator using hot water, and those with pipes containing hot water buried under the floor were very common. The function is very similar to that of a Gudul, so most people using this type of radiator would sleep on the floor. Those people with a traditional Gudul not using them were mostly in Uzbekistan. The reason for this was that the family members had diminished, so it was hard work for elderly parents to manage an extra building containing a Gudul. Gas was the fuel generally used for heating and cooking in Uzbekistan. 4) Guduls were used in the Korean compatriot's houses in all three areas, even though they have changed in structure to adapt to the Russian life style. However, Guduls have still been functioning to maintain a traditional life style in Korean compatriot's houses for the gathering of family members.

• 마케팅과학연구
• /
• 제9권
• /
• pp.77-99
• /
• 2002

기업은 현재 급변하는 기업환경의 변화에 따라 브랜드에 대한 관심이 이론적, 실무적으로 증가하고 있는 시점에 있다. 이는 보다 가치 있는 브랜드를 만들어 내고 이를 지속적으로 관리 및 강화 시켜 나가기 위한 브랜드 자산의 진단 및 관리 모델개발에 대한 필요성이 대두되고 있음을 말해주고 있다. 이러한 배경 아래 본 연구는 실제로 브랜드자산이 소비자의 실제 구매행위에 어떤 영향을 미치는지에 대한 분석을 실증적으로 수행한 연구이다. 다시 말하면, 기업들의 점증하는 체계적 브랜드관리에 대한 필요성을 인식하면서 이에 부응하기 위한 하나의 통합적 브랜드 관리 시스템의 개발로 볼 수 있다. 더욱이 기존의 이론 연구와 실제 현장에서 활용되고 있는 모델들을 통하여 한계점을 찾고, 이를 해결하기 위한 새로운 형태의 브랜드 성과진단 모델로서 본 연구는 그 활용가치가 매우 높다고 할 수 있다. 이론적으로는 단순한 경쟁사와의 차별적 위치를 확보하기 위한 브랜드의 개념보다는 좀 더 확장된 형태의 브랜드자산과 성과에 대한 연구로서 본 연구의 의의를 찾아볼 수 있다. 더욱이 3개의 세분 시장별로 추출한 총 15개의 브랜드에 대한 실증분석을 통하여 제시한 연구모형을 검증하여 보았다. 실증 결과적으로는 세분시장별로 일부 차이는 보이고 있지만 구매행위로 대변되는 브랜드성과는 브랜드파워를 비롯한 여러 연구변수와의 유의한 관계를 가지는 것으로 나타났다. 브랜드의 중요성은 현실적으로 증대되고 있으며, 강한 브랜드를 만들기 위해서는 브랜드관리가 전제되어야 하고, 또한 관리를 위해서는 측정이 수반되어야 한다. 본 연구에서 제시하고 있는 연구모형의 실증적 결과들은 기업들이 보다 브랜드 중심적인 경영 전략을 펼칠 수 있는 당위성을 제시할 수 있을 것이다.

• 방사선산업학회지
• /
• 제5권4호
• /
• pp.337-345
• /
• 2011

In order to provide an effective preparedness for a nuclear or radiological emergency happening in the domestic or neighborhood countries and to solve the vague fear of the people for the ingestion of radioactive livestock products, the establishment of national guideline level for radionuclides in feed is urgently necessary. This is because it is important to secure the safety and to manage the crisis in the agricultural, fishery and food sector by performing the effective safety control during and after nuclear incident. This study was performed to investigate the report cases of international organizations and foreign countries to set up a domestic control standard for managing radioactive substances that may be contaminated in animal feeds due to the nuclear power plant incident. In addition, an attempt was made to provide a useful reference that can help prepare a domestic control standard, using a coefficient that can consider the transfer into livestock through the intake of radioactive contaminated animal feeds. The standard radioisotopes investigated were confined to radioactive cesium ($^{137+134}Cs$) and iodine ($^{131}I$). Guideline level for the radionuclides was calculated by using the transfer coefficient factor and the maximum daily intake of animal feed provided by IAEA. For example, the maximum daily intake of animal feed was set as $25kg\;d^{-1}$ for dairy cows, $10kg\;d^{-1}$ for beef cattle, $3.0kg\;d^{-1}$ for pigs and $0.15kg\;d^{-1}$ for chickens. The result values for radioactive cesium were calculated as $8,696Bq\;kg^{-1}$, $4,545Bq\;kg^{-1}$, $1,667Bq\;kg^{-1}$ and $2,469Bq\;kg^{-1}$, respectively. The results for radioactive iodine showed the ranges between $741Bq\;kg^{-1}$ and $76,628Bq\;kg^{-1}$. These data can be utilized as a scientific reference for the preparation of a crisis management manual for the emergency control due to nuclear power plant accident in Korea and neighboring country. These results will contribute to establish the safe feed management system at national level as manual for responding the radioactive exposure of agricultural products and animal feeds, which are currently not established.