Theoretical Model for Accident Prevention Based on Root Cause Analysis With Graph Theory

Molan, Gregor,Molan, Marija Occupational Safety and Health Research Institute 2021 Safety and health at work Vol.12 No.1

Introduction: Despite huge investments in new technology and transportation infrastructure, terrible accidents still remain a reality of traffic. Methods: Severe traffic accidents were analyzed from four prevailing modes of today's transportations: sea, air, railway, and road. Main root causes of all four accidents were defined with implementation of the approach, based on Flanagan's critical incident technique. In accordance with Molan's Availability Humanization model (AH model), possible preventive or humanization interventions were defined with the focus on technology, environment, organization, and human factors. Results: According to our analyses, there are significant similarities between accidents. Root causes of accidents, human behavioral patterns, and possible humanization measures were presented with rooted graphs. It is possible to create a generalized model graph, which is similar to rooted graphs, for identification of possible humanization measures, intended to prevent similar accidents in the future. Majority of proposed humanization interventions are focused on organization. Organizational interventions are effective in assurance of adequate and safe behavior. Conclusions: Formalization of root cause analysis with rooted graphs in a model offers possibility for implementation of presented methods in analysis of particular events. Implementation of proposed humanization measures in a particular analyzed situation is the basis for creation of safety culture.

Effects of Feeding Condensed Tannin-containing Plants on Natural Coccidian Infection in Goats

Hur, Sam N.,Molan, Abdul L.,Cha, Jang O. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.9

Twelve Korean native goats, spontaneously infected with mixed species of Eimeria were used to study the possible direct anticoccidial effect of feeding condensed tannin-containing plants on the production of Eimeria oocysts. The effects of feeding pine (Pinus densifora) needles, oak (Quercus acutissima) leaves and lucerne chaff on coccidia oocyst output were studied for a period of 10 days post-feeding. The results indicate that feeding fresh pine needles (40 g condensed tannins (CT) dry matter (DM)/day/goat) and oak leaves (40 g CT DM/day/goat) in combination with lucerne chaff had rapid anticoccidial activities in goats as demonstrated by a sharp decrease in oocyst production. Two days after feeding, the numbers of oocysts per gram of faeces (OPG) from the goats fed pine needles with lucerne chaff, and from goats fed oak leaves reduced by 40% and 44% compared to pre-feeding, respectively. On the sixth day after commencing feeding pine needles and oak leaves, the reduction was 81% and 72%, respectively. Ten days after feeding pine needles and oak leaves, the OPG was reduced by 93% and 85%, respectively compared to pre-feeding. Statistical analysis showed that feeding pine needles and oak leaves to goats naturally infected with coccidia significantly (p<0.001) reduced the numbers of oocysts compared to the control group fed lucerne chaff only. Four clinically important species of coccidia, Eimeria parva, Eimeria ninakohlyakimovae, Eimeria christenseni and Eimeria arloingi were identified in Korean native goats.

Technical-Economical Evaluation of Chain Vertical Alignment in Underground Urban Subways: The Case of Qom Subway, Line A

Abdi Kordani, Ali,Mehrara Molan, Amirarsalan The Korean Society for Railway 2014 International Journal of Railway Vol.7 No.2

Urban subways are one of the main parts of urban transportation networks in every city that always requires much attention in order to improve its efficiency in aspects of safety, reliability speed and costs. As the viewpoint of costs, an accurate design, especially design of vertical alignment, can have a dominant role to reduce the costs of urban railway projects. This paper seeks to evaluate the advantages and disadvantages of designing chain vertical alignment for urban subways in compare to flat vertical alignment. To achieve this goal, line A of Qom subway in Iran was selected as a case study in this research. Five parameters considered in the technical-economical evaluation: (1) energy consumption, (2) rolling stock, (3) operation, (4) civil works and geotechnical and (5) hydrological, drainage and pumping. According to the results, a power saving of about 40% have been estimated in the chain vertical alignment for the train without regenerative braking in compare with the flat vertical alignment, although the power saving was calculated less than 10% for the train with regenerative braking. Finally it was found that due to the modern rolling stock technology, the chain vertical alignment represents fewer advantages in compare to the past years.

Technical-Economical Evaluation of Chain Vertical Alignment in Underground Urban Subways

Ali Abdi Kordani,Amirarsalan Mehrara Molan 한국철도학회 2014 International Journal of Railway Vol.7 No.2

Urban subways are one of the main parts of urban transportation networks in every city that always requires much attention in order to improve its efficiency in aspects of safety, reliability speed and costs. As the viewpoint of costs, an accurate design, especially design of vertical alignment, can have a dominant role to reduce the costs of urban railway projects. This paper seeks to evaluate the advantages and disadvantages of designing chain vertical alignment for urban subways in compare to flat vertical alignment. To achieve this goal, line A of Qom subway in Iran was selected as a case study in this research. Five parameters considered in the technical-economical evaluation: (1) energy consumption, (2) rolling stock, (3) operation, (4) civil works and geotechnical and (5) hydrological, drainage and pumping. According to the results, a power saving of about 40% have been estimated in the chain vertical alignment for the train without regenerative braking in compare with the flat vertical alignment, although the power saving was calculated less than 10% for the train with regenerative braking. Finally it was found that due to the modern rolling stock technology, the chain vertical alignment represents fewer advantages in compare to the past years.

The Effect of Combined Horizontal Curve and Longitudinal Grade on Side Friction Factors

Ali Abdi Kordani,Amirarsalan Mehrara Molan 대한토목학회 2015 KSCE JOURNAL OF CIVIL ENGINEERING Vol.19 No.1

The relationship between side friction factor and longitudinal grade is investigated for horizontal curves considered in threedimensions, and new models for estimating side friction factors for different vehicle types are presented. The study consists of threeparts: (1) a series of simulation tests using the CarSim and TruckSim multi-body simulation software packages; (2) multiplexregression analysis; and (3) presentation of recommended formulas for the side friction factor. Two different driving behaviors areconsidered in the simulation process: in one, the driver negotiates the curve at constant speed; in the other, the driver brakes whilepassing downgrades. Side friction factors are also studied separately for each axle of a vehicle. Greater side friction factors are foundon downgrades for all vehicle types when cornering. From the viewpoint of skidding, the most critical situation is found for the rearaxle of a sedan. In addition, braking is found to have a significant effect on side friction factors. The results and models from thisstudy can be used in the geometric design phase by highway engineers to design safer roads.

Geology, Age and Geochemistry of Tertiary Volcanics, Northern Coast of King George Island (South Shetland Islands, West Antarctica)

Krzysztof Birkenmajer,Zheng Xiangshen,Hu Shiling,E. Molan 한국해양과학기술원 1996 KOREAN JOURNAL of Polar Research Vol.7 No.1·2

⁴⁰Ar/³⁹Ar and K-Ar Age Datings on the Volcanic Rocks in Northern Coast of King George Island, West Antarctica

Hu Shiling,Zheng Xiangshen,E Molan,K. Birkenmajer 한국해양과학기술원 1996 KOREAN JOURNAL of Polar Research Vol.7 No.1·2

Characterization of Novel Trichoderma asperellum Isolates to Select Effective Biocontrol Agents Against Tomato Fusarium Wilt

El_Komy, Mahmoud H.,Saleh, Amgad A.,Eranthodi, Anas,Molan, Younes Y. The Korean Society of Plant Pathology 2015 Plant Pathology Journal Vol.31 No.1

The use of novel isolates of Trichoderma with efficient antagonistic capacity against Fusarium oxysporum f. sp. lycopersici (FOL) is a promising alternative strategy to pesticides for tomato wilt management. We evaluated the antagonistic activity of 30 isolates of T. asperellum against 4 different isolates of FOL. The production of extracellular cell wall degrading enzymes of the antagonistic isolates was also measured. The random amplified polymorphic DNA (RAPD) method was applied to assess the genetic variability among the T. asperellum isolates. All of the T. asperellum isolates significantly reduced the mycelial growth of FOL isolates but the amount of growth reduction varied significantly as well. There was a correlation between the antagonistic capacity of T. asperellum isolates towards FOL and their lytic enzyme production. Isolates showing high levels of chitinase and ${\beta}$-1,3-glucanase activities strongly inhibited the growth of FOL isolates. RAPD analysis showed a high level of genetic variation among T. asperellum isolates. The UPGMA dendrogram revealed that T. asperellum isolates could not be grouped by their antagonistic behavior or lytic enzymes production. Six isolates of T. asperellum were highly antagonistic towards FOL and potentially could be used in commercial agriculture to control tomato wilt. Our results are consistent with the conclusion that understanding the genetic variation within Trichoderma isolates and their biochemical capabilities are required for the selection of effective indigenous fungal strains for the use as biocontrol agents.

Characterization of Novel Trichoderma asperellum Isolates to Select Effective Biocontrol Agents Against Tomato Fusarium Wilt

Mahmoud H. El_Komy,Amgad A. Saleh,Anas Eranthodi,Younes Y. Molan 한국식물병리학회 2015 Plant Pathology Journal Vol.31 No.1

The use of novel isolates of Trichoderma with efficient antagonistic capacity against Fusarium oxysporum f. sp. lycopersici (FOL) is a promising alternative strategy to pesticides for tomato wilt management. We evaluated the antagonistic activity of 30 isolates of T. asperellum against 4 different isolates of FOL. The production of extracellular cell wall degrading enzymes of the antagonistic isolates was also measured. The random amplified polymorphic DNA (RAPD) method was applied to assess the genetic variability among the T. asperellum isolates. All of the T. asperellum isolates significantly reduced the mycelial growth of FOL isolates but the amount of growth reduction varied significantly as well. There was a correlation between the antagonistic capacity of T. asperellum isolates towards FOL and their lytic enzyme production. Isolates showing high levels of chitinase and β-1,3-glucanase activities strongly inhibited the growth of FOL isolates. RAPD analysis showed a high level of genetic variation among T. asperellum isolates. The UPGMA dendrogram revealed that T. asperellum isolates could not be grouped by their antagonistic behavior or lytic enzymes production. Six isolates of T. asperellum were highly antagonistic towards FOL and potentially could be used in commercial agriculture to control tomato wilt. Our results are consistent with the conclusion that understanding the genetic variation within Trichoderma isolates and their biochemical capabilities are required for the selection of effective indigenous fungal strains for the use as biocontrol agents.

Postantibiotic Effect of Purified Melittin from Honeybee (Apis mellifera) Venom against Staphylococcus aureus

SangMi Han,KwangGill Lee,JooHong Yeo,SoonOk Woo,HaeYong Kweon,YouYoung Jo,Peter Molan 한국응용곤충학회 2009 한국응용곤충학회 학술대회논문집 Vol.2009 No.05

Since the ancient times the therapeutic application of honeybee venom (BV) is practised and persisted until the present days. Resistant bacteria are in emergence and some drugs no longer have an antimicrobial action. To purify the melittin known as antibacterial peptide, five major peptidergic subfractions were separated, purified and identified from the whole BV. We investigated the antibacterial activity of whole BV and purified melittin against Staphylococcus aureus by the minimum inhibitory concentrations (MIC) and the postantibiotic effect (PAE). The MIC of whole BV for S. aureus was 0.06 ㎍/㎖, respectively. The MIC of melittin was 0.06 ㎍/㎖ on S. aureus. The in vitro PAE of whole BV and isolated melittin were determined using E. coli and S. aureus. The PAE of whole BV against S. aureus were 3.45 h (1×MIC). The PAE of melittin against S. aureus was 4.35 h (1 × MIC). Also both whole BV and melittin killed S. aureus at 5 × MIC. The regrowth wasn't observed after 18 h. These results suggest that whole BV and melittin will be developed a novel antibacterial drug.