فصلنامه دانش پیشگیری و مدیریت بحران
سال دوازدهم شماره 4 (پیاپی 46، زمستان 1401)

Natural and unnatural disasters have claimed many lives and destroyed many urban spaces and communities. The consequences of these threats and today's urban issues have raised the need for action for resilient cities. December 2019 was the time for the outbreak of coronavirus in China, a disease that quickly spread throughout the world and disrupted human life.

In this regard, the present descriptive-analytical research aims to collect information through library data and valid Persian and English magazines and articles to extract important indicators related to the resilience of neighborhoods against Corona and with a future approach. Research and help analyze them from Mic Mac software.

According to the studies, during the research, 61 factors affecting the resilience of neighborhoods against corona were identified, which were performed with Mick software and diagrams extracted from those analyzes.

The results show that among the factors affecting the resilience of neighborhoods against Corona that were examined, most of them were in the independent and dependent category and "population density" and "neighborhood crisis management programs" from They are the main factors in this area, in the sense that these two factors have a great impact on the resilience of neighborhoods to the Corona virus, which should be given special attention.

Crises provide very short time to make decisions by creating unexpected and unstable conditions. Lack of preparation before crises, can lead to widespread negative consequences such as disorder, fragility, disintegration, instability, threat to values and conflict. In the last two decades, the issue of resiliency has been addressed due to the dramatic increase in damages caused by over concentration of people and resources in urban areas. Resilience is a multifaceted concept, so planning for physical resilience can be considered as one of the most important factors in reducing the effects of hazards. However, there are still serious ambiguities in the detailed explanation of physical resilience criteria and the importance and priority of each of them, which has led to a serious problem in determining planning priorities in urban development plans. Therefore, the aim and endeavor of this research is to state the most important criteria of physical resilience and then determine their importance. In this way, it will help to redefine the priorities in resiliency planning in the management of the country's cities.

This research is applied in terms of essence and descriptive-analytical in terms of method with using quantitative IAHP method. Documentary studies, exploratory interviews and the results of the expert panel were used in data collection.

This research, after reviewing various texts and sources and the opinions of professors and urban planning professionals, has explained seventeen criteria of physical resilience in three levels and five fields and has determined the coefficient of preference and priority of action in urban development plans.

Creating the change in the state of physical resilience, requires long-term planning, application of urban planning and architectural technical criteria, significant investment and continuous monitoring of executive results, which in many cases is beyond the capacity of urban administrations. Therefore, by formulating a specific action plan, the criteria that cause the most damage if ignored should be prioritized for correction and implementation. However, the importance of other criteria should not be neglected.

The spatial structure of cities depends on the different and mutual relationships of all forces and factors in the city. These factors include market forces, activities, urban infrastructures and various services, which always have a complex and reciprocal relationship. In today's world, one of the basic challenges in cities is to create a balanced spatial structure that plays an important role in sustainable development. Development and creating an efficient multi-core spatial structure in metropolises like Tehran requires a balanced spatial distribution of population and activity cores. The factors of population and activity are the main elements of the spatial structure that have a direct and main effect on the creation or non-creation of desirable urban cores. The Aim of this research is to evaluate and analyze the spatial structure of Tehran metropolis from the perspective of population and activity indicators in order to determine the state of balance or imbalance of the spatial structure as well as the state of urban functional cores.

The research method is descriptive-analytical and based on spatial statistics calculations. The information and data used are collected from official and library sources and include information related to urban activities in the field of employment. The activities are listed in seven (7) main industrial, commercial, administrative, educational and recreational, cultural and medical categories and are considered as functional cores. In order to analyze the distribution of functional cores of activities and the population of Tehran and the spatial patterns of activities, the methods of mean center, standard deviation ellipse, nearest neighborhood mean and geographical weighted regression (GWR) have been used.

The results of this research regarding the distribution of the spatial structure of the city of Tehran based on the indicators of activity and population and the relationship between these two indicate that the activity nuclei are in the form of a single nucleus and in some components in the form of multiple cores and the pattern of distribution of functional cores in the city has a cluster pattern.

Based on the results of geographic regression, there is an effective relationship between functional cores and population distribution in the city of Tehran, and this situation causes and aggravates traffic problems and congestion in the metropolis of Tehran. In this regard, it is necessary to strengthen the functional role of areas in which the relationship between these two indicators is weak (Region's 15-22-5-18) in order to reduce the burden of traffic and congestion in other saturated areas of the city (Region's 3-6-7-11-12) And also be strengthened the multi-core spatial structure of the city.

The severity of natural disasters in many rural parts of the country is such that the continuation of the social and economic life of the residents of these areas always faces a crisis. Villages are more vulnerable to natural disasters and hazards due to their traditional structure and texture compared to cities, and every year, natural disasters cause a lot of damage to the country's villages. Therefore, the current research was conducted with the aim of designing and validating a local model for managing natural disasters and accidents in villages in two qualitative (Delphi method) and quantitative stages.

This research is exploratory in terms of purpose and descriptive in terms of type, which was carried out by field method. The sample population of the research, in the qualitative stage, 30 people from the managers of the crisis headquarters of Ardabil province, who were selected purposefully and by the method of chain referral sampling (snowball method). Also in the second stage, based on the Morgan table, there were 384 people from the residents of the villages of Ardabil province with at least A diploma was chosen. The data collection tool in the qualitative stage was an in-depth and semi-structured interview with experts, which was conducted in three rounds using the Delphi method, and in the quantitative stage, the redesigned questionnaire resulting from the first stage was used.

In this research, the extracted indicators, based on the studied variables as well as the results of the third round of Delphi, were categorized into 7 more effetive factors (preparedness, reaction, backlash, evaluation, physical, managerial, restoration and reconstruction) and 32 concepts (open codes).

The results of the research showed that the "evaluation" dimension and the "physical" dimension with a path coefficient of 0.859 have had the greatest impact on the management model of accidents and natural disasters in villages. Finally, by using Smart PLS software, the fit of the obtained model was ensured and all significant relationships were detected.

Emergency evacuation is one of the first stages of crisis management, which should be done in the shortest possible time and can have a great effect in reducing the death rate caused by the occurrence of danger. So the purpose of this article is to evaluate the emergency evacuation time of Mehrabad Airport in emergency situations through the simulation of emergency population evacuation strategies.

The research method is descriptive-analytical, in terms of solving the combined problem and the type of explanatory results. Collecting field and documentary information has been done. The statistical population includes 53 specialists, academic staff and graduate students. Random sampling and Cochran's formula were used. After conducting the interview and completing the questionnaire, the scenarios with a maximum of two incompatible factors were obtained from the Wizard software, and then the fifth scenario and two modes A and B were modeled in the Any Logic software.

The simulation results have shown. The evacuation time in the fifth scenario is higher than the other scenarios because the inspection room itself has a gate that reduces the speed of people leaving and increases the time required for people to leave. The results show that in case B, the time has increased compared to case A, in fact, in case A, 3600 people leave the place in 98 minutes, and in case B, the same number of people leave the place in 105 minutes. The reason for the increased time in mode B is because only the obstacles on the path are removed and the door is not added.

It can be concluded that only removing the obstacles is not an efficient method to reduce the evacuation time and the emergency door should also be added to the model. Also, according to the fifth scenario, the resilience of airport hall number 2 is not suitable in emergency situations because in the event of a crisis and an increase in congestion, the level of fear and speed is very high. In fact, in the event of a crisis, the airport in question is able to safely evacuate when the number of people exceeds 1000, since the number of people in normal conditions is 2000. Unlike the previous researches that had a one-dimensional look at the issue of emergency evacuation, this article has a mixed approach.

Risk reduction is one of the pillars of sustainable development of society. The aim of the research is Validation of effective factors in crisis management of emerging infectious diseases with a focus on covid-19 disease so that the managers of the organizations can gain benefits while having a systemic thinking and a suitable management model while passing along with health.

This is a survey-cross-sectional study. Data collection was done through questionnaires. The statistical population of the research includes all the informants on the issue of corona crisis management of the selected organizations of Khuzestan province in year 2022. According to Cochran's formula, the sample number is 384 people who tried to complete the questionnaire. Structural equation model with SmartPLS version 3 and SPSS version 23 software was used to validate the model.

The results, based on the opinion of experts, showed that causal factors have an impact on management of emerging infectious diseases. management of emerging infectious diseases has an impact on strategies. Contextual factors and intervening factors influence management of emerging strategies. Finally, strategies have an impact on the consequences of management of emerging. Also Q2, F2 ,  R2 (0.272) and GOF (0.440) indices showed that the fit of the measurement, structural and general models was appropriate and confirmed.

In the midst of a crisis, managers will be able to take advantage of a suitable management model by planning, organizing, coordinating and continuously monitoring in order to prevent and reduce the adverse consequences of crises; While passing along with health by learning lessons and designing a model for better management of these crises, they should take steps to design other crisis management models and models so that they can accumulate knowledge in the field of crisis management of such emerging diseases, and from this accumulation of knowledge and experience for the coming years and management to deal with possible new similar diseases and use better decisions.

human settlements have faced various crises since long ago, of which the earthquake crisis was one of the most common; Therefore, in order to manage the crisis, it is necessary to evaluate the vulnerability of different areas of the city in the face of that crisis and to plan for it according to the vulnerability of each area. Khorram Abad city is located in an area with high vulnerability to earthquakes, and the present study seeks to measure the vulnerability of Khorramabad areas to earthquakes.

The research method is applied in terms of purpose, and in terms of data collection, it is a descriptive-analytical research, and in terms of data type, it is a quantitative research. In this research, using the detailed plan of 2014, the statistical blocks of 2015, and the opinions of 15 experts, the indicators were compiled and analyzed using the hierarchical analysis method of AHP with the use of Expert Choice 11 software, and to identify and prioritize the risk zones of the city areas. Khorram Abad against earthquake using ArcGIS 10.8 software.

In evaluating the vulnerability of urban areas in terms of earthquakes, building quality factors, age of the building structure, facade materials, number of floors, landuse, building density, width of roads, slope percentage, distance from fault, distance from green and open space, distance From the location of fuel, distance from medical centers, population density and worn-out fabric are effective. Also, the most important factors affecting the vulnerability of Khorramabad city areas to earthquakes include fabric wear, building quality, building age, and distance from the fault.

According to the results of the research, the central and southeastern areas of the city, which include 31% of the studied area, are in the high spectrum in terms of vulnerability, that is, areas 5 and 4 are the most vulnerable areas against earthquakes, followed by areas 7 and 17. , 18, 19 and 20 are highly vulnerable; and the remaining 52 percent have a good condition; The northeastern areas of the city are in the low vulnerability range, and areas 9, 16, 22 and 24, which comprise 17% of the studied area, have the least vulnerability to earthquakes.