• 한국위험물학회지
• /
• 제6권2호
• /
• pp.7-12
• /
• 2018

Hydrochloric acid is a highly corrosive toxic substance and requires proper safety to minimize damage in case of leakage. Among the various risk-reduction facilities, the dike is a typical safety facility installed to protect the surrounding buildings and facilities by preventing the external spread of hazardous materials from the storage tank. In this study, the KORA program was used to assume leakage accident of hydrochloric acid storage tank. At this time, the extent of the damage effects of ERPG-2 were assessed for each of the three separation distance between the storage tank and the dike. The study found that the smaller the separation distance between the dike and the storage tank, the smaller the extent of damage caused by hydrochloric acid leakage, and the greater the impact of indoor conditions under the same conditions. Through this process, we are going to assist in selecting locations and installing facilities for new and existing businesses.

• 한국수소및신에너지학회논문집
• /
• 제34권6호
• /
• pp.734-740
• /
• 2023

Hydrogen emphasis on safety management due to its high potential for accidents from wide explosive limits and low ignition energy. To prevent accidents, appropriate explosion-proof electrical equipment with installed to safe management of ignition sources. However, designing all facilities with explosion-proof structures can significantly increase costs and impose limitations. In this study, we optimize the barrier to effectively control the initial momentum in case of hydrogen release and form the control room as a non-hazardous area. We employed response surface method (RSM), the barrier distance, width and height of the barrier were set as variables. The Box-Behnken design method the selection of 15 cases, and FLACS assessed the presence of hazardous area. Analysis of variance (ANOVA) analysis resulting in an optimized barrier area. Through this methodology, the workplace can optimize the barrier according to the actual workplace conditions and classify reasonable hazardous area, which is believed to secure safety in hydrogen facilities and minimize economic burden.

• Animal Bioscience
• /
• 제37권8호
• /
• pp.1474-1482
• /
• 2024

Objective: The experiment aimed to determine the standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in 10 brown rice samples fed to pigs, and to construct predictive models for SID of CP and AA based on the physical characteristics and chemical composition of brown rice. Methods: Twenty-two cannulated pigs (initial body weight: 42.0±1.2 kg) were assigned to a replicated 11×3 incomplete Latin square design, including an N-free diet and 10 brown rice diets. Each period included 5 d adaptation and 2 d ileal digesta collection. Chromic oxide was added at 0.3% to all the diets as an indigestible marker for calculating the ileal CP and AA digestibility. Results: The coefficients of variation of all detected indices for physical characteristics and chemical composition, except for bulk weight, dry matter (DM) and gross energy, in 10 brown rice samples were greater than 10%. The SID of CP, lysine (Lys), methionine, threonine (Thr), and tryptophan (Trp) in brown rice was 77.2% (62.6% to 85.5%), 87.5% (80.3% to 94.3%), 89.2% (78.9% to 98.9%), 55.4% (46.1% to 67.6%) and 92.5% (86.3% to 96.3%), respectively. The best prediction equations for the SID of CP, Lys, Thr, and Trp were as following, SID_CP = -664.181+8.484×DM (R² = 0.40), SID_Lys = 53.126+6.031×ether extract (EE)+0.893×thousand-kernel volume (R² = 0.66), SID_Thr = 39.916+7.843×EE (R² = 0.41), and SID_Trp = -361.588+4.891×DM+0.387×total starch (R² = 0.85). Conclusion: Overall, a great variation exists among 10 sources of brown rice, and the thousand-grain volume, DM, EE, and total starch can be used as the key predictors for SID of CP and AA.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
• /
• pp.1705-1711
• /
• 1991

On-line fault detection and diagnosis has an increasing interest in a chemical process industry, especially for a process control and automation. The chemical process needs an intelligent operation-aided workstation which can do such tasks as process monitoring, fault detection, fault diagnosis and action guidance in semiautomatic mode. These tasks can increase the performance of a process operation and give merits in economics, safety and reliability. Aiming these tasks, series of researches have been done in our lab. Main results from these researches are building appropriate knowledge representation models and a diagnosis mechanism for fault detection and diagnosis in a chemical process. The knowledge representation schemes developed in our previous research, the symptom tree model and the fault-consequence digraph, showed the effectiveness and the usefulness in a real-time application, of the process diagnosis, especially in large and complex plants. However in our previous approach, the diagnosis speed is its demerit in spite of its merits of high resolution, mainly due to using two knowledge models complementarily. In our current study, new knowledge representation scheme is developed which integrates the previous two knowledge models, the symptom tree and the fault-consequence digraph, into one. This new model is constructed using a material balance, energy balance, momentum balance and equipment constraints. Controller related constraints are included in this new model, which possesses merits of the two previous models. This new integrated model will be tested and verified by the real-time application in a BTX process or a crude unit process. The reliability and flexibility will be greatly enhanced compared to the previous model in spite of the low diagnosis speed. Nexpert Object for the expert system shell and SUN4 workstation for the hardware platform are used. TCP/IP for a communication protocol and interfacing to a dynamic simulator, SPEEDUP, for a dynamic data generation are being studied.

• 한국안전학회지
• /
• 제27권6호
• /
• pp.78-83
• /
• 2012

In this study, some experimental results of the peroxide-degradation process of polypropylene(PP) in a co-rotating twin-screw extruder to produce controlled rheology polypropylene(CRPP) are presented. The peroxide was dicumyl peroxide(DCP) and the concentration of DCP was in the range 0-0.3 wt%. It was found that the rheological properties of PP change significantly during reactive extrusion. Melt flow index(MFI) increased with DCP concentration. Intrinsic viscosity decreases with increasing DCP concentration. From dynamic rheological data, number average molecular weight(Mn), weight average molecular weight(Mn) and molecular weight distribution(MWD) were calculated. Results indicated that Mw decreases and MWD becomes narrower with increasing peroxide concentration. Especially, particle size distribution of CRPP decreases with increasing DCP concentration by chemical powdering process, and anti-slip floor paint, CRPP(DCP 0.2 wt%) powder by 10phr was friction coefficient 2.15 ${\mu}$, abrasion resistance 511.18%.

• 한국가스학회지
• /
• 제20권1호
• /
• pp.7-12
• /
• 2016

천연가스는 장거리 수송을 위해서는 액화가 필수적으로 이루어진다. 액화공정 내 압축기에서 특히 많은 동력이 요구되며, 동력을 공급하기 위해서는 동력기가 필요하다. 여러 가지 동력기 중 어떠한 동력기를 선택하느냐에 따라 동력 공급에 필요한 비용이 변하게 된다. 본 연구에서는 최소의 비용으로 천연가스 액화공정에 동력을 공급하는 최적의 동력기 선택을 위해 최적화를 수행하였다. 또한 가스전의 용량을 고려하여 일정한 가스전에서 천연가스가 추출부터 소멸될 때까지의 전체기간 동안에 추출되는 속도가 변경되는 시나리오를 구성하였다. 공정모사를 통해 동력기 장치의 비용과 운전비용 간의 상관관계를 예측하였으며, 장치의 수명 등을 고려하여 모델링하였다. 그 결과 최대 6.4%의 비용을 감소하는 최적의 동력기 모델을 설계하였다.

• International Journal of Safety
• /
• 제2권1호
• /
• pp.34-38
• /
• 2003

The lower and upper flash points of the flammable binary system, butylacetate+2-propanol were measured by air blowing tester. The shape of the concentration-temperature region of flash depended on the components of the mixture in solution. The experimental data were compared with the values calculated by the reduced model under an ideal solution assumption and the flash point-prediction models based on Van Laar equation. Good qualitative agreement was obtained with these models. The prediction results of these models can thus be applied to incorporate inherently safer design for chemical process, such as the determination of the safe storage conditions for flammable solutions.

• Nuclear Engineering and Technology
• /
• 제55권8호
• /
• pp.2773-2784
• /
• 2023

It is essential to evaluate the blasting-enhanced permeability (BEP) feasibility of a low-permeability sandstone-type uranium deposit. In this work, the mineral composition, reservoir physical properties and rock mechanical properties of samples from sandstone-type uranium deposits were first measured. Then, the reformability evaluation method was established by the analytic hierarchy process-entropy weight method (AHP-EWM) and the fuzzy mathematics method. Finally, evaluation results were verified by the split Hopkinson Pressure Bar (SHPB) experiment and permeability test. Results show that medium sandstone, argillaceous sandstone and siltstone exhibit excellent reformability, followed by coarse sandstone and fine sandstone, while the reformability of sandy mudstone is poor and is not able to accept BEP reservoir stimulation. The permeability improvement and the distribution of damage fractures before and after the SHPB experiment confirm the correctness of evaluation results. This research provides a reformability evaluation method for the BEP of the low-permeability sandstone-type uranium deposit, which contributes to the selection of the appropriate regional and stratigraphic horizon of the BEP and the enhanced ISL of the low-permeability sandstone-type uranium deposit.

• 한국식품위생안전성학회지
• /
• 제15권3호
• /
• pp.267-270
• /
• 2000

본 연구에서는 유해한 화학물질인 vinyl chloride에 대한 건강 위해성 평가의 주요한 단계인 용량-반응 평가(dose-response assessment)를 수행함에 있어서 실험동물을 대상으로 한 발암성 자료를 사용하여 인체 위해도(risk)를 예측하고자 하였다. 용량 반응 평가에서는 고농도의 독성 자료로 부터 인체에 노출되는 수준인 저농도로 외삽을 위하여 computer software를 사용하지 않고 직접 다양한 통계 모델링을 사용하여 위해도를 산출하였다 이는 추후 국내 화학물질의 위해도 평가시 광범위하게 활용될수 있는 기초자료를 제공할 것이다.

• 에너지공학
• /
• 제18권1호
• /
• pp.63-68
• /
• 2009

조직의 안전 문화는 연구기에 매우 복잡하고 힘들다. 그러나 문화를 만든 표준들을 검사하는 것은 가능하다. 이 논문 화학 공업과 같은 높은 위험 산업에서 개발된 공정안전관리 분위기 평가 도구를 다루고 있다. 주된 목적은 측정소프트웨어 도구를 개발하는 것으로 안전분위기와 문화를 평가하기 위해 널리 알려진 기술들과 관련된 문헌들을 재검토 하였으며 대상 집단에 대한 면접과 토론도 실시하였다. 재검토와 대상 집단에 바탕을 두고 안전 분위기 평가 설문과 온라인 적용 프로그램을 개발하였으며 화학공장에 대해 시범적 평가를 적용한 후 윤곽을 완성하였다. 그리고 관리상의 문화적인 변화를 측정할 수 있는 프로토콜을 제안하였고, 이 프로토콜을 토대로 사업장에서 안전문화를 조기에 정착시킬 수 있는 계기가 될 수 있도록 지원할 수 있는 안전문화(Safety Climate) 측정 도구를 전산화 하였다.