• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.6
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• pp.525-538
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• 2014

Safety of reactive systems is one of the most important research areas in the field of weapon development. A NoGo response or at least a low-order explosion should be ensured to prevent unexpected accidents when the reactive system is impacted by high-velocity projectile. We investigated the shock-induced detonation of cased reactive systems subject to a normal projectile impact to the cylindrical surface based on two-dimensional hydrodynamic simulations using the I&G chemical rate law. Two types of energetic materials, namely LX-17 and AP-based solid propellant, were considered to compare the dynamic responses of the reactive system when subjected to the threshold impact velocity. It was found that shock-to-detonation transition phenomena occurred in the cased LX-17, whereas no full reaction occurred in the propellant.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.4
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• pp.518-527
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• 2014

Objectives: The adverse health effects attributed to exposure to radon have been well known over the world. However, the efforts for prevention and mitigation of radon have not been taken in Korea so far. The purpose of this study was to evaluate the effectiveness of mitigation methods applied for various types of houses and public buildings with high level of radon. Methods: Based on the results of "National Radon Survey" performed by the National Institute of Environmental Research(NIER) in 2010-2012, we selected 30 candidate buildings consisting of 20 houses and 10 public buildings with greater than $148Bq/m^3$ of radon level. We measured the concentration of radon in 30 buildings, using E-PERMs and RAD-7 during January to March of 2013. More than five E-PERMs and one RAD-7 per house were installed for seven days. Ten houses and five public buildings were finally chosen to be mitigated after mainly considering the level of radon and the location of buildings nationwide. Three mitigation methods such as Sealing, two types of Active Ventilation(window-shaped and wall-typed ventilations), and Active Soil Depressurization(ASD) were applied, and the concentrations of radon were measured before and after mitigation, respectively. To evaluate the effectiveness of mitigation methods, reduction rates of radon were calculated and Wilcoxon's signed-rank test was performed. Results: The mean concentration of 15 buildings just before radon mitigation was $297.8Bq/m^3$, and most of the buildings were located in Gangwon, Chungbuk, Chungnam, and Daegu areas(73.3%), and built in 1959-1998. The level of radon decreased from 48% to 90% and kept the below recommendation limit of $148Bq/m^3$ after installation of radon mitigation. Among mitigation methods applied, the reduction rate(58.7-90.4%) of radon attributed to ASD was the greatest than that of other methods, followed by Active Ventilation(48.4-78.4%) and Sealing(<22%). The effectiveness of radon reduction by window-shaped Active Ventilation(63.2-75.2%) was relatively better than that of wall-typed Active Ventilation(48.4-54.3%). Conclusions: The results of this study indicate that ASD could be more effective for radon mitigation. Moreover, our findings would be background information in future for making the strategy for radon mitigation nationwide, as well as for developing Korean-version of mitigation techniques according to types of dwellings in Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2159-2165
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• 2013

Cancer registries help to establish and maintain cancer incidence reporting system, serve as a resource for investigation of cancer and its causes, and provide information for planning and evaluation of preventive and control programs. However, their wider role in directly enhancing oncology drug access has not been fully explored. We examined the value of cancer registries in oncology drug access in the Asia-Pacific region on three levels: (1) specific registry variable types; (2) macroscopic strategies on the national level; and (3) a regional cancer registry network. Using literature search and proceedings from an expert forum, this paper covers recent cancer registry developments in eight economies in the Asia-Pacific region - Australia, China, Hong Kong, Malaysia, Singapore, South Korea, Taiwan, and Thailand - and the ways they can contribute to oncology drug access. Specific registry variables relating to demographics, tumor characteristics, initial treatment plans, prognostic markers, risk factors, and mortality help to anticipate drug needs, identify high-priority research area and design access programs. On a national level, linking registry data with clinical, drug safety, financial, or drug utilization databases allows analyses of associations between utilization and outcomes. Concurrent efforts should also be channeled into developing and implementing data integrity and stewardship policies, and providing clear avenues to make data available. Less mature registry systems can employ modeling techniques and ad-hoc surveys while increasing coverage. Beyond local settings, a cancer registry network for the Asia-Pacific region would offer cross-learning and research opportunities that can exert leverage through the experiences and capabilities of a highly diverse region.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.8
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• pp.781-788
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• 2013

Predicting the engine component temperature is a basic step to conduct structural safety evaluation in medium-speed diesel engine design. Recent trends such as increasing power density and performance necessitate more effective thermal management of the engine for achieving the desired durability and reliability. In addition, the local temperatures of several engine components must be maintained in the proper range to avoid problems such as low- or high-temperature corrosion. Therefore, it is very important to predict the temperature distribution of each engine part accurately in the design stage. In this study, the temperature of an engine component is calculated by using steady-state conjugate heat transfer analysis. A proper approach to determine the thermal load distribution on the thermal boundary area is suggested by using 1D engine system analysis, 3D transient CFD results, and previous experimental data from another developed engine model. A Hyundai HiMSEN engine having 250-mm bore size was chosen to validate the analysis procedure. The predicted results showed a reasonable agreement with experimental results.

• Journal of the Korean GEO-environmental Society
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• v.13 no.11
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• pp.93-101
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• 2012

SCP is a construction method that maximizes the effects of ground improvement by creating sand piles, which are formed by the compaction within soft ground. SCP is mainly used for consolidation and drain effects in clayey soils, and as a liquefaction countermeasure through effects such as compaction in loose sandy soils. In the design of SCP, if the sand piles with high stiffness are not taken into account, it can become a design that overly considered safety, and increased construction costs are highly likely to cause economic disadvantages. The changes in stress conditions and compaction mechanisms in the subsurface have been identified to a certain extent by study findings to date. However, the studies that considered SCP and in-situ ground as composite ground are fairly limited, and therefore, those studies have not achieved enough results to fully explain the relevant topics. In this study, the ground improved by SCP was regarded as the composite ground that consists of SCP and in-situ ground. Moreover, employing a CID test, this study examined the changes in the stress conditions of in-situ ground according to the installation of SCP through the relations between $K_0$ and SCP replacement ratio. At the same, whether the SCP installation procedure can be recreated in a laboratory was examined using a cyclic triaxial test. According to the test results, the changes in the stress conditions of the original ground occurred most largely in an initial stage of SCP installation, and after a certain time point, the vibration for SCP installation did not have a great influence on the changes in the stress conditions of the ground. Moreover, in order to recreate the behaviors of in-suit ground according to SCP in a laboratory, cyclic loading, which corresponds to casing vibration, was concluded to be essentially required.

• The Korean Journal of Emergency Medical Services
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• v.13 no.1
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• pp.87-96
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• 2009

Purpose : To grasp the mental burden for legal responsibility that rescue members have in the performance of job. Method : Questionnaire was presented to rescue members serving in 2 direct control safety centers of fire station located in Seoul, Daejon, Incheon, Kwangju, Busan, Daegu and Ulsan. Results : 1. Questioned whether they have mental burden for legal responsibility while performing job on the site, the rescue members responded : very burdensome in 38.0%, burdensome in 56.0%, moderate in 4.5%, not burdensome in 1.0%, no burden at all in 0.5%. 2. Questioned on the first aid treat for which they have the most mental burden, the rescue members responded : intubation into trachea laryngeal mask airway(LMA) in 40.4%, automatic external defibrillator in 16.3%, securing vein providing sap(medicine) in 10.8%, basic cardiopulmonary resuscitation in 7.2%, eliminating foreign matters inserted into body in 5.4%, stanching external bleeding and treating injury in 5.4%, fixing extremities and spine by using splint in 1.8%, measuring the symptom of vitality in 1.2%, providing oxygen in 0.0%. 3. Questioned whether experiencing legal problem or firm petition(complaint) raised by patient while serving as rescue members, they responded : experiencing a complaint in 41.6%, experiencing no complaint in 58.4%. Asked to indicate the stress level in the scale of which they suffered when lawsuit or firm petition was raised, 0(weak)-10(strong), they answered 8.8 in average. 4. Questioned whether 119 rescue members put the legal responsibility in case that they cause damage to patients intentionally in performing, they responded to the inquiry 3.66 in average(of 5.00). It represented meaningful differences (F=2.874, p=.024) whether they had license or not. 5. In future, legal action will raise against the rescue member by 99% because of people's rights improvement(63.1%), high expectations for the rescue system(29.5%), non-licensed rescue members(5.1%). Conclusion : It was found that the rescue members had severe mental burden for advanced life support which was investigated to have low enforcement rate in the preceding research, for instance, intubation into trachea securing vein management by using automatic external defibrillator. To improve the qualitative level of rescue service in the fire fighting, it may be required to construct the environment that eliminates the mental burden of rescue members for legal responsibility.

• Economic and Environmental Geology
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• v.48 no.4
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• pp.351-360
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• 2015

Hamangun Dohangri $6^{th}$ tumulus was characterized by using geological, geophysical, and geotechnical surveys in terms of the shape of the tombs, origin and geotechnical properties of tomb materials, safety of grave mound and burial chamber. The bedrock (Haman Formation sedimentary rock) forming the ground of the tomb, is weathered such that men can excavate the ground. The mound tomb is classified into soil part and rock part by low resistivity and high resistivity, respectively, through electrical resistivity survey. The burial chamber is mostly made by Haman Formation while some part is composed of granitic rock that is distributed in the most southern district of the study area. According to soil tests, the soil part of mound tomb shows low water content, low pore ratio, and proper unit weight that indicate highly compacted material. Additionally, the mound tomb is safe because the strength of the rock part of the mound tomb exceeds that of general rock.

• Korean Journal of Social Welfare
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• v.63 no.3
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• pp.109-131
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• 2011

This qualitative study aimed to explore and understand the impacts of the poor neighborhood on children from their own perspectives. To this end, the meaning and the structure of children's lived experiences were explored. The participants were recruited from elementary school high grade students living in poor neighborhood. Focused group interviews were conducted in each of the 24 World Visions social work agencies. The collected data were analysed qualitatively. According to the results, the following main themes could be extracted from the children's lived experiences: "Conflict between connection and differentiation", "Resigning to the fate of being neglected in danger" "Learning to live in the dark cave", "Anticipating a bowl of trust from the neighborhood". The children living in poor neighborhood were threatened by the physical and emotional danger highly probable in weak social infrastructure. Also, they have internalized negative self-identity by chaotic environment and, even the negative role models from alcoholic and sometimes violent adults. However, they were experiencing positive caring from and solidarity with surrounding neighborhood, and were participating in volunteered activities for asserting their citizen rights. These may be the keys to empowerment and, ultimately, to change for themselves and the community. The implications of the study results for the policy making and the actual practice were discussed focusing on the children's rights and well-being.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.12
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• pp.1106-1113
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• 2013

For patients who have senile mental disorder such as dementia, quantity of excercise and amount of sunlight are important clue for dose and the treatment. Therefore, monitoring health information of daily life is necessary for patients' safety and healthy life. Portable & wearable sensor device and server configuration monitoring data are needed to provide these services for patients. Watch-type device(smart watch) which patients wear and server system are developed in this paper. Smart watch developed includes GPS, accelerometer and illumination sensor, and can obtain real time health information by measuring the position of patients, quantity of exercise and amount of sunlight. Server system includes the sensor data analysis algorithm and web server that doctor and protector can monitor through sensor data acquired from smart watch. The proposed data analysis algorithm acquires quantity of exercise information and detects step count in patients' motion acquired from acceleration sensor and to verify this, the three cases with fast pace, slow pace, and walking pace show 96% of the experimental result. If developed u-Healthcare System for dementia patients is applied, more high-quality medical service can be provided to patients.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2551-2562
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• 2013

Since 2006, an Intelligent Excavation Robot which automatically performs the earth-work without operator has been developed in Korea. The technologies for automatically recognizing the terrain of work environment and detecting the objects such as obstacles or dump trucks are essential for its work quality and safety. In several countries, terrestrial 3D laser scanner and stereo vision camera have been used to model the local area around workspace of the automated construction equipment. However, these attempts have some problems that require high cost to make the sensor system or long processing time to eliminate the noise from 3D model outcome. The objectives of this study are to analyze the advantages of the existing 3D modeling sensors and to examine the applicability for practical use by using Analytic Hierarchical Process(AHP). In this study, 3D modeling quality and accuracy of modeling sensors were tested at the real earth-work environment.