• Explosives and Blasting
• /
• v.14 no.1
• /
• pp.49-63
• /
• 1996

Blasting is a work that destruct an object by use of explosive. Its use covers a wid range, and it is applicable to blast the rocks, minerals, coal, steel and concrete structures, bridges, etc. To execute the blast plan most effectively, the properties of the object and the explosives should be well understood, and all the other conditions must ve incorporated in its design and plan. A safe blasting pattern and procedure should be selected considering the envirinmental effects and dther conditions. At the same time, a protective protective pricedures should be utilized to prevent the safety hazards such as the excessive blast vubration, air pressure, and the flying fragments. This study reviews the controlled blasting techniques in these regards.

• International Journal of Contents
• /
• v.6 no.3
• /
• pp.89-96
• /
• 2010

The International air transportation industry provides a vital communication link which brings prosperity to many states in our modern age. This invaluable link has been threatened by terrorism. Airlines have been one of the most attractive targets in the eyes of terrorists for several reasons, including particularly the international and symbolic nature of aviation, and the potential of multigovernmental involvement which can inevitably generate wide publicity. Terrorist attacks against civil aviation have been committed since the earliest days of civil aviation history. The first attack against civil aircraft dates back to the early 1930s. Since then, aircraft hijacking and other forms of attack against air transport operations have become one of the most serious challenges to the safety of flying. In recent years, a new form of threats against civil aviation has appeared. Man-portable air defense systems (MANPADS) in the hands of criminals, terrorists, and other non-state actors pose a serious potential threat to passenger air travel, the commercial aviation industry, and military aircraft around the world. The purpose of this study is to provide some countermeasures against such attacks. In order to foster a better understanding of the problem, an introduction of MANPADS and a brief history of attacks using MANPADS are presented. It also examines the level of threats, trends of attacks using MANPADS and the possible countermeasures to be taken by the international community.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.22 no.3
• /
• pp.15-23
• /
• 2014

There have been CFIT(Controlled Flight Into Terrain) accidents that can be prevented if the crew executed go-around. This study is to analyse the common factors of three typical CFIT accidents of Korea in TEM(threat and error management) frame, and the examples of go-around gate and the countermeasures of eight airlines through the survey facilitating go-around to prevent CFIT. The common factors found in three typical CFIT accidents occurred in Korea or by Korean carriers turned out to be in mountainous terrain, in bad weather while in non-precision approach or circling approach by captain as PF(Pilot Flying) when crew make monitoring errors and communication errors. It also turned out that the crew in all three typical tragic CFIT accidents did not execute go-around in unstabilized approaches. The captains did not respond immediately when first officers advised them to go-around until it is too late. Seven out of eight Airlines answered that they use stabilized approach height as 1,000 feet to be stabilized earlier to have more safety margin by enhancing go-around gate regardless of the weather to prevent CFIT in the survey.

• Journal of the Optical Society of Korea
• /
• v.18 no.5
• /
• pp.605-610
• /
• 2014

Clouds play an important role in climate change, in the prediction of local weather, and also in aviation safety when instrument assisted flying is unavailable. Presently, various ground-based instruments used for the measurements of the cloud base height or velocity. Lidar techniques are powerful and have many applications in climate studies, including the clouds' temperature measurement, the aerosol particle properties, etc. Otherwise, it is very circumscribed in cloud velocity measurements because there is no Doppler effect if the clouds move in the perpendicular direction to the laser beam path of Doppler lidar. In this paper, we present a method for the measurement of cloud velocity using lidar's range detection and DIC (Digital Image Correlation) system to overcome the disadvantage of Doppler lidar. The lidar system acquires the distance to the cloud, and the cloud images are tracked using the developed fast correlation algorithm of DIC. We acquired the velocities of clouds using the calculated distance and DIC algorithm. The measurement values had a linear distribution.

• Journal of Aerospace System Engineering
• /
• v.9 no.1
• /
• pp.12-18
• /
• 2015

The inter-conversion between different control laws in flight has a lot of risk. The SWM(Switching Mechanism) including logic and stand-by mode is designed to analyze the transient response of aircraft during inter-conversion between different control laws, based on the in-house software for non-real-time and real-time simulation. The SWM applies the fader logic of TFS(Transient Free Switch) to minimize the transient response of an aircraft during the inter-conversion, and applies the reset '0' type of the stand-by mode to prevent surface saturation due to integrator effect in the disengaged flight control law. The transition time is also important to minimize the objectionable transient response in the inter-conversion, as well as the transition control law design. This paper addresses the results of non-real-time simulation for the characteristics of transient response to different transition time to select the adequate transient time, and the real-time pilot evaluation, using SSWM(Software Switching Mechanism) and HSWM(Hardware Switching Mechanism), which is met for Level 1 flying qualities and assures safety of flight.

• Explosives and Blasting
• /
• v.24 no.2
• /
• pp.75-82
• /
• 2006

Most of limestone mines in Korea have been developed by a open-cut mining method in consideration of a deposited condition of ore, ore recovery, safety, economic efficiency, etc.. But it has produced environmental problems such as dust flying, blasting noise & vibration, and spoil of farmlands due to slope failure of waste rock mass caused by access road construction, fragmentation & crush of rocks, blasting, transportation, and mineral processing. In this study, it has been suggested for measures to reduce mine hazards caused by open- cut mining of limestone nines.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.22 no.4
• /
• pp.87-92
• /
• 2014

In spite of ICAO's effort to ensure the safety of flight operation by requiring crews, controllers, and other ground aviation staffs to use unified system for units, SI (System International of units), there are still many aircrafts designed, manufactured, and operated based on non-SI units, and many crew training in airline companies are also conducted based on non-SI. Due to this confusion of using different unit systems in international flight operation, many crew members and passengers are exposed to danger. International flights pilots may have confusion while flying different airspaces of different countries that use different unit systems, and this may cause human errors causing accidents and incidents. Due to these reasons, it is needed to establish the standards to reflect non-SI that many countries practically use to SI, which is international standard.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.27 no.2
• /
• pp.47-53
• /
• 2019

The development of the aviation industry and the changes in the military operation mission environment are demanding more long - distance operation (long - time flight), and such a flying environment is a risk factor for fatigue - related accidents. For the aviation related organizations such as ICAO and FAA, fatigue risk management system (FRMS) are applied along with flight time restriction regulations to prevent fatigue related accidents. The most important process in FRMS is fatigue risk management. Fatigue risk management systematically manages fatigue through scientific fatigue risk data collection and fatigue risk assessment. The purpose of this study is to applicate the assessment of scientific fatigue risk management to pilots of airplanes engaged in long flight. We reviewed the current state of risk management and FRMS through previous research. We also developed fatigue risk management indicators and examined the validity of internationally recognized fatigue risk data collection methods and fatigue risk assessment tools. There are 134 mission (flight) data used for development. In order to verify the indicators, the fatigue risk score between the items was assigned through pair-wise comparison. In addition, the verify test results were normalized.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.29 no.4
• /
• pp.45-51
• /
• 2021

A runway safety area (RSA) is defined as the surface surrounding the runway prepared or suitable for reducing the risk of damage to airplanes in the event of an undershoot, overshoot, or excursion from the runway. The Runway Stripe is a defined area including the runway stopway, if provided, intended firstly to reduce the risk of damage to aircraft running off a runway, and secondly, to protect aircraft flying over it during takeoff or landing operations. This study used 2 RSA analysis models; RSARA and LRSARA. The analysis utilizes historical data from the specific airport and allows to take into consideration specific operational conditions to which movements are subject, as well as the actual or planned RSA conditions in terms of dimensions, configuration, and boundaries defined by existing obstacles. This study applied the RSA and LRSA risk assessment models to a domestic airport that do not meet the criteria required by standards for aerodrome physical characteristics. The airport is considering a method to secure the runway strip standard through the displaced threshold. This study intends to confirm through quantitative risk estimation whether meeting facility standards through the runway displaced threshold leads to a positive change in risk mitigation.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.30 no.2
• /
• pp.44-54
• /
• 2022

An empirical analysis was conducted on the workload of helicopter pilots flying in high-risk flight environments such as ground obstacles and weather effects at low altitudes. To evaluate the workload, an independent sample t-test was performed using the NASA-TLX evaluation method most suitable for the aviation field, and the workload score was calculated by applying the analytical stratification method (AHP) to compare and analyze private and commercial pilots. There is a significant difference in mean between private and commercial pilots and the result of work load was obtained over 70%. This paper studied the 'surprise and startle effect' on the helicopter field for the first time. In the future, it is intended to contribute to the safe operation of helicopters by presenting a method for effective safety management by utilizing it in the field of education and training for helicopter pilots and providing basic data for preventing accidents caused by human error.