• 한국컴퓨터정보학회논문지
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• 제25권10호
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• pp.125-133
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• 2020

본 연구에서는 Internet of Things(IoT) 시스템에서 최소의 메모리 및 프로세서 자원을 사용하는 4계층의 TCP/IP에 관하여 연구하고 설계한다. 본 연구에서 설계한 TCP/IP는 다음과 같은 특징을 가지고 있다. 첫째, 메모리 할당량을 최소화하여 메모리 자원을 최소로 사용한다. 둘째, 메모리 복사량을 최소화하여 프로세서 자원을 최소로 사용한다. 셋째, TCP/IP의 수행 시간이 고정 시간에 완료될 수 있다. 넷째, 메모리 누수 문제가 발생하지 않는다. 본 연구에서 도출된 메모리 할당량 및 복사량에 대한 최소 자원 기준은 기 구현된 IoT 시스템의 통신 서브시스템이 효율적으로 구현되었는지를 점검하기 위해 유용하게 사용될 수 있다. 최근 리눅스 재단에서 발표한 공개 소스 커널인 Zephyr의 통신 서브시스템의 메모리 할당량 및 복사량을 측정한 결과, 본 연구에서 도출한 최소 자원 기준보다 더 크다는 것을 발견하였다. 본 연구에서 제안한 설계 방법에 따라 Zephyr 통신 서브시스템을 개선하여 메모리 할당량 및 복사량이 각각 약 39% 및 67% 감소함을 확인하였으며, 이에 따른 수행 시간도 약 28% 감소하였다.

• Mycobiology
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• 제38권1호
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• pp.39-45
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• 2010

White rot, which is caused by Sclerotium cepivorum, is a lethal disease affecting green onions. Three different types of nanosilver liquid (WA-CV-WA13B, WA-AT-WB13R, and WA-PR-WB13R) were tested in several different concentrations on three types of media to assess their antifungal activities. Results from in vitro experiments showed that all three of the nano-silver liquids had more than 90% inhibition rates at a concentration of 7 ppm. Greenhouse experiments revealed that all of the nano-silver liquids increased biomass and dry weights, and there were minimal changes in the population of various bacteria and fungi from the soil of greenhouse-cultivated green onions. In addition, a soil chemical analysis showed that there were minimal changes in soil composition.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
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• pp.23-26
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• 2004

Recently, most of countries in the world are investing huge amount of capital for the infrastructure of logistics and trying to gain dominating position in logistics. To play the role of important hub in logistics, an efficient, flexible, and fault-tolerant transportation process should be developed. Minimization of transportation cost and timely deliveries in the unpredictable environment are a few of the important issues in logistics. This study suggests a way of transporting goods to destinations at the minimal cost and with the minimal delay by optimally allocating transporting resources. Various attributes in transportation such as due date, priority etc. are also considered. Appropriate transporting resources for each work item is selected by calculating the weighted sum of the cost factor and the delay factor assuming that initial sequences of work items are given. A policy to reallocate transporting resources is also suggested when work items or transporting resources are added or deleted because of accidents or disturbances. This policy provides adaptability to the allocation methodology which enables the system to cope with changing environment by controlling various attributes in transportation. Genetic algorithm is used for this approach.

• 대한산업공학회지
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• 제35권1호
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• pp.58-72
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• 2009

The main activities of container terminals are to load container freights to vessels, discharge them from vessels, and store them in the storage yard. Container terminals make many operational plans to execute these functions effectively. If the plans do not consider enough the loads of related resources, they may have low actualities. This study discusses the optimal yard planning model which considers various resources, such as the storage yard, yard cranes, internal vehicles, and travel lanes, in container terminals. The model determines the groups and amounts of containers which are stored in each storage block by using the resource profile. The yard planning problem is represented to the multi-commodity minimal cost flow problem and is formulated to the linear programming model. In order to explain the application of the mathematical model, the numerical examples are presented. Additionally, the relationship between the average load ratio and the relocation ratio is discussed.

• 한국도서관정보학회지
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• 제28권
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• pp.61-91
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• 1998

In contemporary education, a school library is considered and valued as a vital and integral component of a school's instructional program. Especially, school library materials should contribute to execution of school curriculums through wide provision of resources. The results of the study are as follows. 1. The term 'library materials' should be changed into 'library resources' with a broad meaning. And, the scope of school library materials should include printed materials, audio-visual materials, electronic materials, associated equipment and other library resources. 2. It is desirable that the minimal standards of total collection is 5 books and 3 AV for a student in elementary schools, 7 books and 5 AV for a student in middle schools, 10 books and 7 AV for a student in high schools. 3. Annual growth is 0.5 for a student in elementary schools, 1 for a student in middle schools and 1.5 copy for a student in high schools. And, the number of minimal serials is 20 titles in elementary schools, 30 titles in middle schools and 50 tides in high schools. 4. Besides, basic collection, with the advances of technology, the school library collection should include new formats and delivery systems such as CD, video discs, videotex, computer software, satellite transmission etc. 5. The recommendable annual ratio of withdrawl is 3 to 5% for update and functional materials.

• 식물분류학회지
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• 제41권3호
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• pp.209-214
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• 2011

The taxonomy of the umbelliferous species Angelica amurensis and its allies was reviewed on the basis of molecular phylogenies derived from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) regions. Strict consensus of six minimal length 119-step trees derived from equally weighted maximum parsimony analysis of combined nuclear rDNA ITS1 and ITS2 sequences from 29 accessions of Angelica and outgroups indicated that Angelica purpuraefolia, known to be endemic to Korea, is the same species as A. amurensis. Comparisons of sequence pairs across both spacer regions revealed identity or 1-2 bp differences between A. purpuraefolia and A. amurensis. These results indicated that the two taxa are not distinguished taxonomically. Also, nuclear rDNA ITS regions are discussed as potential barcoding loci for identifying Korean Angelica.

• Journal of the Korean Wood Science and Technology
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• 제33권2호통권130호
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• pp.24-28
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• 2005

Monte Carlo simulation was performed on theoretical models of plywood warp for southern yellow pine plywood originating from the United States. The objective of the investigation was to determine which plywood layers was more warp sensitive to veneers that were manufactured to an undesired thickness. This study found that for a balanced panel (a panel of equal target thickness for each of five layers) manufactured veneers of undesired thickness would experience minimal warp. The veneers of undesired thickness placed in the center of the plywood panel also provided a minimum change of plywood warp properties. The panel warp was very sensitive to surface veneers constructed with undesired thickness. Conversely, this study confirms that monitoring of veneer thickness and proper allocations within the plywood lay-up were critical.

• 생물환경조절학회지
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• 제22권3호
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• pp.241-247
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• 2013

돌나물 유전자원의 기내 활성보존을 위하여, 10mm 크기의 기내배양 shoot를 agar, Gelrite, ABA 및 sucrose 농도를 달리한 MS 배지에 치상하여, $4^{\circ}C$와 $25^{\circ}C$에서 계대배양 없이 보존하였다. 배지는 $0.2mg{\cdot}L^{-1}$ BA를 기본으로 첨가하였고, agar와 Gelrite 배지에는 5% sucrose, ABA 배지에는 5% sucrose와 1.2% agar, sucrose 배지에는 1.2% agar를 각각 첨가하였다. 상온 활성보존($25^{\circ}C$)에서 sucrose와 Gelrite 배지는 생장억제 효과가 거의 없었고, $0.2mg{\cdot}L^{-1}$ BA + $10mg{\cdot}L^{-1}$ ABA + 1.2% agar, 또는 $0.2mg{\cdot}L^{-1}$ BA + 1.6% agar를 첨가한 배지가 효과적이었으며, 계대배양 없이 10개월까지 활성보존이 가능하였다. 저온 활성보존($4^{\circ}C$)에서 12개월후 생존율은 모든 배지에서 100%였으며, $10mg{\cdot}L^{-1}$ ABA, 또는 6% sucrose 첨가배지에서 계대배양 없이 18개월 이상의 활성보존이 가능하였다. 특히 고농도 sucrose 배지는 저온 활성보존($4^{\circ}C$)에서 돌나물 유전자원의 장기간 활성유지에 가장 효과적이었다.

• 한국토양비료학회지
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• 제44권4호
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• pp.650-656
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• 2011

Lysobacter antibioticus HS124 isolated from pepper rhizosphere soil produced catechol type siderophore. Purified siderophore by Diaion HP-20 and silica gel column chromatography showed several hydroxyl functional groups adjacent to benzene rings by analysis of $^1H$ NMR spectroscopy. The strain HS124 showed different activities to suppress Phytophthora capsici with different concentrations of exogenous Fe (III) in minimal medium where antifungal activity with $100{\mu}M$ Fe (III) was approximately 1.5 times higher than in absence of Fe (III). Bacterial population in this Fe (III)-amended medium was also highest with $8.9{\times}10^8\;CFU\;ml^{-1}$ which also corresponded to the strongest siderophore activity. When grown in rich medium (minimal medium with N, $P_2O_5K_2O$ and glucose), HS124 exhibited approximately 2 times stronger antifungal activity compared to minimal medium. In pot trials, treatments of bacterial culture grown in rich medium with (C1) or without (C2) $100{\mu}M$ Fe (III) exhibited a high protection of pepper plants from disease, compared to medium only with (M1) or without (M2) $100{\mu}M$ Fe (III). Especially, treatment C1 showed the best disease control effect of about 70 %. Thus, the strain HS124 should be recommended as a potential biocontrol agent against P. capsici in pepper.

• 한국축산식품학회지
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• 제37권4호
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• pp.518-528
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• 2017

Quality characteristics of frozen cylindrical pork loin were evaluated following different tempering methods: 27.12 MHz curved-electrode radio frequency (RF) at 1000 and 1500 W, and forced-air convection (FC) or water immersion (WI) at $4^{\circ}C$ and $20^{\circ}C$. The developed RF tempering system with the newly designed curved-electrode achieved relatively uniform tempering compared to a parallel-plate RF system. FC tempering at $4^{\circ}C$ was the most time-consuming process, whereas 1500 W RF was the shortest. Pork sample drip loss, water holding capacity, color, and microbiological quality declined after WI tempering at $20^{\circ}C$. Conversely, RF tempering yielded minimal sample changes in drip loss, microstructure, color, and total aerobic bacteria counts, along with relatively uniform internal sample temperature distributions compared to those of the other tempering treatments. These results indicate that curved-electrode RF tempering could be used to provide rapid defrosting with minimal quality deterioration of cylindrical frozen meat block products.