• 한국대기환경학회지
• /
• 제21권6호
• /
• pp.573-583
• /
• 2005

Fugitive dust, which is emitted in the ambient air without first passing through a stack or duct designed to control flow, is frequently generated by means of wind erosion from storage yards at Pohang Steel Wokrs. The size distribution of fugitive dust is mostly in the range of coarse particulate which is deposited as soon as emitted and less harm to human health; however $20\%$ of fugitive dust contains PM 10 known as one of most harmful airborne pollutant. Consequently, effective control and reduction of fugitive dust is strongly requested by the local society, but it is not easy so far because the generation and dispersion of fugitive dust highly depends on meteorological conditions, and it being occurred for irregularity. This research presented a fugitive dust control system for each meteorological condition by providing statistical prediction data obtained from a statistical analysis on the probability of generating the threshold velocity at which the fugitive dust begins to occur, and the frequency occurring by season and by time of the wind direction that can generate atmospheric pollution when the dispersed dust spreads to adjacent residential areas. The research also built a fugitive dust detection system which monitors the weather conditions surrounding storage yards and the changes in air quality on a real-time basis and issues a warning message by identifying a situation where the fugitive dust disperses outside the site boundary line so that appropriate measures can be taken on a timely basis. Furthermore, in respect to the spraying of water to prevent the generation of fugitive dust from the storage piles at the storage yard, an advanced statistical meteorological analysis on the weather conditions in Pohang area and a case study of fugitive dust dispersion toward outside of working field during $2002\∼2003$ were carried out in order to decide an optimal water-spraying time and the number of spraying that can prevent the origin of fugitive dust emission. The results of this research are expected to create extremely significant effects in improving surrounding environment through actual reduction of the fugitive dust produced from the storage yard of Pohang Steel Works by providing a high-tech warning system capable of constantly monitoring the leakage of fugitive dust and water-spray guidance that can maximize the water-spraying effects.

• 한국건축시공학회지
• /
• 제16권4호
• /
• pp.381-388
• /
• 2016

제설전진기지는 제설작업을 신속하게 수행하기 위한 물리적인 제반요건으로서, 제설대상 도로구간에 필요한 제설차량 및 장비를 보관한 차고와 제설제를 비축한 창고, 관리시설 등을 구비한 시설물로 정의할 수 있다. 본 연구는 제설전진기지의 시설기준을 마련하기 위한 기조적 연구로서 해외의 기준을 고찰하고 고속국도 및 일반국도, 지방도를 대상으로 국내 제설전진기지의 실태를 조사하였다. 사례조사결과 창고형태의 전진기지가 없고 야외에 제설제를 보관하고 있는 경우도 많은 것으로 나타났다. 실태조사를 바탕으로 배치, 규모, 평면, 구조체로 나누어 문제점을 분석하고 제설전진기지의 설계시 고려사항을 제시하였다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제32권6호
• /
• pp.881-890
• /
• 2019

Objective: A study was conducted to develop non-dairy creamer analogs/mimics using egg white, egg yolk, soy protein and their combinations, and their nutrient content, shelf-life and flavor acceptability were compared. Methods: Spray dried egg white, egg yolk, and soy protein isolate were purchased from manufacturers and used for the formulae. Results: The protein contents of the non-dairy creamer analogs/mimics were about 8.5% as calculated. The amounts of oleic and linoleic acid content increased as the amount of yolk increased in the formula, but the increases of polyunsaturated fatty acids were <0.5% of total fat. Addition of egg yolk to the formula increased choline and lutein content in the products, but the amounts were <0.4 mg/g for choline and $4{\mu}g/g$ for lutein. The lutein in the products continued to decrease over the storage time, and only about 15% to 20% of the 0-month amounts were left after 3 months of storage. Although the thiobarbituric acid reactive substances values of the spray-dried non-dairy creamer analogs/mimics increased as storage time increased, the values were still low. Yellowness, darkness, and egg flavor/odor of the non-dairy creamer analogs/mimics increased as the amount of egg yolk in the formula increased. The overall acceptability of the non-dairy creamer analogs/mimics was closely related to the intensity of egg flavor/odor, but storage improved their overall acceptance because most of the off-odor volatiles disappeared during the storage. Water temperature was the most important parameter in dissolving spray-dried non-dairy creamer analogs/mimics, and $55^{\circ}C$ to $75^{\circ}C$ was the optimal water temperature conditions to dissolve them. Conclusion: Higher amounts of yolk and soy protein combinations in place of egg white reduced the cost of the products significantly and those products contained better and balanced nutrients than the commercial coffee creamers. However, off-flavor and solubility were two important issues in the products.

• 한국주거학회논문집
• /
• 제26권4호
• /
• pp.75-82
• /
• 2015

Although the government has revised the child welfare act, institutionalized the establishment of local children's centers, and given financial support for them, there are a number of problems with respect to their operation. Specifically, one of main problems is their limited space. Diverse problems that go with the arrangement of limited space and usability have occurred, however there are only a few strategies to use limited space flexibly. This study assumed variability as one of the methods to solve spatial problems. As a basic research for the assumption, Analyzing the variable method and characteristics of domestic and foreign child-care facility guidelines was performed trying to take advantage of as a basic data in order to seek a variable scheme of local children centers' indoor space. For this purpose, study analysed the methods and characteristics of variability centering on aspects related to variability which are environmental design elements required by local children's centers as suggested in previous studies. The results are as follows. First, the variability of space should be planned according to activity and time, and consider the methods of division, storage, and other facilities necessary. Second, methods of variability in space can be classified into creating areas and structures that are variable. Third, as a result of analysing the environmental design elements required by local children's centers, this study discovered the following characteristics: multi-purpose usability through a combination of variable devices, transition through a variable space medium and setting up areas and expansion of indoor variability assuming usability through internal and external connections.

• 한국작물학회지
• /
• 제39권4호
• /
• pp.382-388
• /
• 1994

저장기간과 용도에 따른 대두종실의 건물 및 화학성분의 변화를 비교하기 위하여 장려 3품종에 대하여 2년의 저장기간 차이를 두었으며 용도에 따라서는 장려 5품종과 재래 2품종을 공시재료로 하여 종실을 종피와 자엽(유근포함)으로 분리하여 건물중, 발아율, 단백질, 지방, 전분, 당 및 oligo당을 분석하였다. 1. 3년 저장된 종자에서 건물중의 감소가 나타났으며, 발아율도 급격히 저하되었다. 2. 저장기간동안 자엽의 무게가 현저히 감소하였고, 종피의 구성비율은 증가하였다. 3. 3년 저장된 종자의 종피에서는 단백질, 지방, 탄수화물이 모두 감소하였고, 자엽에서는 단백질의 함량이 41.65%로 현저하게 감소하였다. 4. 종피의 구성비율은 대립종보다 소립종에서 높았다. 5. 밥밑콩에서 자엽의 단백질과 지방함량은 평균 43.59%와 18.25%로 장려품종에 비해 낮았고, 전분과 당의 함량은 평균 5.70%와 11.58%로 현저하게 높았다. 6. Sucrose, raffinose 및 stachyose의 함량은 밥밑콩에서 높았다.

• 한국축산식품학회지
• /
• 제33권3호
• /
• pp.390-394
• /
• 2013

The aim of this study was to determine the optimal storage condition of pre-packed Hanwoo beef without freezing. Hanwoo loin was purchased from a local distributor at 48 h after slaughter, then sliced in $1.5{\pm}0.5$ cm thickness, and packed in a polyethylene (PE) tray covered with linear low-density polyethylene (LLDPE) film. The studied factors to set the optimal storage condition were chamber temperature (5, 2.5 and $-1^{\circ}C$ for 14 d), cooling method (direct and indirect cooling system), and ultraviolet (UV) light irradiation for beef surface sterilization (0, 30, 60, and 120 min). The changes of pH, thiobarbituric acid reactive substances (TBARS) and number of aerobic bacteria were measured during storage. Beef samples stored in $-1^{\circ}C$ showed the minimal increasing rate in TBARS and microbial growth. After 15 d of storage, there was no significant difference in pH and TBARS values. However, the microbial population of beef stored in direct type cooling chamber ($4.25{\pm}0.66$ Log CFU/g) was significantly lower than that of beef stored in indirect type chamber ($6.47{\pm}0.08$ Log CFU/g) (p<0.05). After 4 d of storage, 60 or 120 min UV light irradiated beef samples showed significantly lower microbial population, and at 14 d of storage, 60 min UV irradiated beef sample showed significantly lower microbial population ($3.14{\pm}0.43$ Log CFU/g) than control ($4.46{\pm}0.13$ Log CFU/g) (p<0.05). However, TBARS values of 60 or 120 min UV light irradiated beef samples were significantly higher than non-irradiated beef sample after 4 d of storage (p<0.05).

• Journal of international Conference on Electrical Machines and Systems
• /
• 제1권4호
• /
• pp.425-433
• /
• 2012

As the demand for electric power increases rapidly and the amount of fossil fuels decreases year by year, making use of renewable resources seem very necessary. However, due to the discontinuous nature of renewable resources and the hierarchical topology of existing grids, power quality and grid stability will deteriorate as more and more distributed generations (DGs) are connected to the grids. It is a good idea to combine local utilization, local consumption, energy storage and DGs to form a grid-friendly micro grid, these micro grids can then assembled into an intelligent power system - the smart Grid. It can optimize power flow and integrate power generation and consumption effectively. Most importantly, the power quality and grid stability can be improved greatly. This paper depicts how the smart grid addresses the current issues of a power system. It also figures out the key technologies and expectations of the smart grid.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1996년도 하계학술대회 논문집 A
• /
• pp.37-40
• /
• 1996

Cable-In-Conduit Conductor(CICC) is widely accepted as an advanced superconductor configuration for large scale applications such as tokamak fusion reactors, MAGLEV (MAGnetic LEVitation), and SMES (Superconducting Magnetic Energy Storage). The stability of CICC cooled with supercritical helium can be very high if it is operated below a certain limiting current. This limiting current can be determined by Stekly type heat balance equation. The stability characteristic of CICC for AC operation is more complicated than that of DC because there are additional instability sources which are associated with local flux change. Ramp-rate limitation is a phenomenon discovered during US-DPC (United States-Demonstration Poloidal Coil) program, which showed apparent quench current degradation associated with high dB/dt. This paper describes recent experimental investigation results on the ramp-rate limitation and discusses current imbalance, induced current, current redistribution due to local quench of the strand in the cable.

• 한국음향학회:학술대회논문집
• /
• 한국음향학회 1992년도 학술논문발표회 논문집 제11권 1호
• /
• pp.29-32
• /
• 1992

In this paper, a systolic array structure is derived from the realization of 2-D IIR digital filters directed from the SFG(signal flow graph). After realized the 1-D formed partial systolic array, we implemented the complete systolic array to be cascaded 1-D form. The cascading of partial systolic arrays reduce the storage element which sued to delay input signal. 1-D systolic array is derived from that DG is designed through local communication approach and then it mapping to SFG. The derived structure is very simple and has high throughput because during new imput sample is supplied, new output is obtained every sampling period. And broadcast input signal is eliminated. Since the systolic array has property of regularity, modularity, local interconnection and highly synchronized multiprocessing, thus is very suitable for VLSI implementation.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2001년도 가을 학술발표논문집 Vol.28 No.2 (3)
• /
• pp.856-858
• /
• 2001

분산 파일 시스템에서 파일을 복제하는 목적의 하나는 파일의 가용성을 높이는 것이다 서버들로 이루어진 시스템에서 가용도 문제는 주로 오류 상황이 대상이다 반면에 데스크탑으로 구성된 경우 각각이 상대적으로 가용도가 낮고 그 편차도 커서 파일의 가용도를 최적화 하도록 복제본을 저장하는 것이 기본적인 문제가 된다. 파일 단위 복제 기법에서는 파일 수가 참여 시스템 수에 따라 기하급수적으로 증가하고 파일 배치 때마다 가용도 최적화를 수행해야 하는 문제가 있다. 본 논문에서는 저장 공간 단위 복제 기법을 제안한다. 데스크탑 시스템의 저 장롱간을 고정 크기의 페이지들로 나누고 이들을 조합해서 일정한 가용도를 가지는 페이지 그룹을 형성한다. 파일들은 이 페이지 그룹에 저장된다. 페이지의 개수가 파일 수가 아닌 시스템 수에 의존하고, 파일 배치 시점과 무관하게 페이지 그룹을 만들 수 있는 장점이 있다. 최종 가용도를 높이고 연산 시간을 줄이기 위해 ILS(Iterated Local Search )방법을 이용만 탐색을 수행한다.