• 한국안전학회지
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• 제26권3호
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• pp.63-68
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• 2011

Access-control of hazard zone in a steel manufacturing industry is studied in terms of safety management. Based on the results of risk evaluation for hazard zone, three risk zones with low, middle and high level are categorized. These zones have different color door and locking shape depending on their risk levels. At the high level, red door and key-based locking system are employed to accessed-controled path. Furthermore, tagout, lockout, interlock system for emergency stop, warning and flashing are also introduced. New standardized procedure of access-control for various hazard zones, which could help to greatly contribute to the prevention of accidents in advance, is proposed considering the risk level and the condition of given hazard zones. The standardized procedure of access-management suggested in this study will take an effective role as one of safety guide lines for hazardous workshop of manufacturing industries.

• 한국조경학회지
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• 제34권6호
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• pp.10-21
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• 2007

The purpose of this paper was to classify areas demanding to be transformed to green spaces and evaluate their grades for urban park and green networks. The results of this study are summarized below; 1. The results of the classified green spaces in the research areas fall into three types including children parks, neighborhood parks, and public green spaces. The three types of green spaces were analysed with recreational indexes. The zones disturbing the green-networks were sorted out. These zones should be changed into a supplementary green spaces for improving the recreational functions in the city. 2. For urban park and green networks, distances between the parks and size of the parks were adopted as indices. Based on the index of distances between the parks, disturbing zones were evaluated with 3 grades. The first grade includes primary industrial complexes and housing complexes. The second grade was observed mostly in industrial complex areas. The third grade includes housing complexes. Based on the indexes of size of parks, disturbing zones were evaluated with 2 grades. In the case of grade I, it appeared in housing complex. In the case of grade II, it appeared in industrial complex. 3. Then, we prioritized the disturbing zones with severity in order to make supplementary green spaces. Through the process, the zones of the grade I for two each recreational index were evaluated to two grades. The analysis results of evaluated zones were that grade II appeared over industrial and housing complexes widely. Grade I appeared over housing complexes. 4. It is necessary that the grade of disturbing zones should be considered as an order to make green spaces to supplement a green-network. For this, we formed a basic frame of a green-networks in Dalsu-Gu and placed the disturbing zones on the basic frame of a green-network. Consequently, The results were that the green-networks in Dalsu-Gu was composed on four green-network axes and its shape mirrored a cruciform (+) of northwest$\leftrightarrow$southeast direction and southwest$\leftrightarrow$northeast direction.

• 한국환경복원기술학회지
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• 제20권6호
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• pp.1-19
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• 2017

This study set out to identify problems with amphibian habitation by the wetland types and improve their habitation environment in urban forest wetlands, thus creating a habitat for amphibians. Study site include forest swamps in Jatjul Park as well as Yeoji neighborhood Park in Guro-gu, and in Choansan neighborhood Park in Dobong-gu. The forest swamp in Jatjul Park gets its water from Mt. Maebong and it is a former escalated farmland-turned wetland. The swamp area is $2,500m^2$, a forest zone and a landscape planting site are 83.27% and 6.70% each. Target species Seoul pond frogs are inseparable from rice fields because they live in a short radius of and lay eggs in or near paddy fields, and Rana nigromaculata have similarities with Rana plancyi chosenica in choosing their habitats. There was need for paths that would lead to other paths so amphibians would spread to other parts of the forest and for measures to secure open water. Modifying a variety of routes for water, human and animals along with building a buffer to keep the core habitation zones were required. The forest swamp in Yeonji neighborhood Park used to be a water reservoir on the foot of Mt. Gunji. The swamp area is $1,980m^2$, a forest zone and farmland account for 80.61% and 4.88% each. Non-point pollutants from upstream along run into the subject forest marsh, bare ground on the around swamp and steep stone embankments obstructed amphibians. Target species was Bufo gargarizans that live in forests and edges of hills and spawn in deep water. The forest swamp in Choansan neighborhood Park gets its water from Mt. Choan and it is close to its water source that it is a mountain stream forest wetland. The basin and the swamp are $35,240m^2$ and $250m^2$ in size respectively. A forest zone accounts for 90.20%, high stone embankments laid in refurbishing the valley obstruct amphibians and there is water shortage in times of droughts. Target species were Rana coreana, Rana dybowskii and Hynobius leechii that live in mountain valleys, streams and wetlands and lay eggs in forest marshes and rocks in valleys. Looking into the three swamps of amphibian habitation, I came to conclusions that those wetlands were suitable for their amphibians but man-made facilities blocked their corridors leading to other corridors and even killed off target species in some parts of those swamps by destroying those parts. Amphibians live in water, on ground and underground at different stages of life. Hence, we should take this fact into consideration when planning their habitats and design core habitation zones, buffers zone and use zones accordingly. Buffer zones ought to be between core habitation zones and surrounding trees. Aiming at protecting core habitation zones, buffers should be in harmony with habitation zones. Use zones should be minimized in size and not in direct contact with core habitation zones.

• Journal of Power Electronics
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• 제16권1호
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• pp.287-296
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• 2016

Conventional maximum power point tracking (MPPT) methods are ineffective under partially shaded conditions because multiple local maximum can be exhibited on power-voltage characteristic curve. This study proposes an improved cuckoo search (ICS) MPPT method after investigating the cuckoo search (CS) algorithm applied in solving multiple MPPT. The algorithm eliminates the random step in the original CS algorithm, and the conception of low-power, high-power, normal and marked zones are introduced. The adaptive step adjustment is also realized according to the different stages of the nest position. This algorithm adopts the large step in low-power and marked zones to reduce search time, and a small step in high-power zone is used to improve search accuracy. Finally, simulation and experiment results indicate that the promoted ICS algorithm can immediately and accurately track the global maximum under partially shaded conditions, and the array output efficiency can be improved.

• 대한의용생체공학회:의공학회지
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• 제28권5호
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• pp.628-635
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• 2007

We studied the effect of vibratory stimulations of different leg muscles, tibialis anterior(TA) and triceps surae(TS), and plantar zones in ten healthy subjects during 1) quiet standing, 2) forward lean of body, 3) backward lean of body, 4) right lean of body, and 5) left lean of body. The experiments were performed on the force platform. The effect of vibration were measured by monitoring the area of COP(Center of pressure) sway. The subjects wore a vibratory stimulation system on foot and ankles and were given the instruction not to resist against the applied perturbations. The results show that all vibratory stimulations to lower limb muscles and plantar zones reduced the COP sway area. This reduction of the COP sway area occurred also in partial vibratory stimulations during quiet standing. In forward lean of body, vibratory stimulations to TA reduced the COP sway area. During backward lean of body, vibratory stimulations to TS reduced the COP sway area. When the subject was tilted right, vibratory stimulations to left plantar zone reduced the COP sway area. During left lean of body, vibratory stimulations to right plantar zone reduced the COP sway area. Thus, the influence of vibratory stimulations to leg muscle and plantar zones differed significantly depending on the lean of body. We suggest that the vibration stimuli from leg muscles and plantar zones could be selectively used to help maintaining postural balance stable.

• 한국환경복원기술학회지
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• 제25권1호
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• pp.57-74
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• 2022

Seed zones were constructed using temperature and precipitation data for the Korean Peninsula and were described as 65 zones. Seed zones for South Korea were reclassified, and they were classified into 34 districts. This study was conducted to define the spread of 5 native seed species (Pinus densiflora, Quercus acutissima, Quercus variabilis, Acer pictum, Carpinus tschonoskii) by linking the seed zones with MaxEnt. The emergence point of native seeds was acquired through the 1:5,000 Forest Type Map and the 4th national natural environment survey data. Based on the MaxEnt result, regions with a habitat probability of 0.5 or more were extracted and overlapped with seed zones to identify the native seed habitat. After analyzing the climate regions with high habitat density, regions with high habitat density of native seeds for each administrative district were identified. In the case of Pinus densiflora, Quercus acutissima, and Quercus variabilis, the Winter minimum temperature(WMT) -9.4~-6.6℃, Annual Heat:Moisture(AH:M) 19~24℃/m was 37%, 43%, and 34%, respectively. occupied the largest area. In Acer pictum, WMT -6.6~-3.8℃ and AH:M 16~19℃/m accounted for 42% of the area, and Carpinus tschonoskii had WMT -3.8~-1.1℃, AH:M <16℃/m Districts accounted for the largest area at 33%. The regions with high density of Pinus densiflora, Quercus acutissima, and Quercus variabilis by administrative district were distributed in high density in Seoul, Southern Gyeonggi-do, Chungcheong-do, and Gyeongsangbuk-do. Acer pictum was distributed in high density in Jeolla-do and Gyeongsang-do, and Carpinus tschonoskii in Jeju, Jeollanam-do and Gyeongsangnam-do. Through this study, seed zones for each of the 5 native seeds were established, and it is expected to provide basic data for the management of native seeds.

• 한국지구과학회지
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• 제30권5호
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• pp.646-659
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• 2009

The early Ordovician graptolites from the upper part (Tumok Member) of the Mungok Formation of the Namaeri and Baeiljae sections at Yeongwol consist of five species belonging to five genera. They are Adelograptus cf. tenellus, Callograptus sp., Dendrograptus suni, Dictyonema sp., and Psigraptus jacksoni. Of these 5 species, Psigraptus is the most excellent index fossil for international correlation with the early Ordovician strata. Adelograptus cf. tenellus from the Mungok Formation of the Namaeri and Baeiljae sections is also recognized with especially short stipe relative to Adelograptus tenellus. Three graptolite zones (such as Adelograptus, Psigraptus, and Dendroid type zones) are correlated with those of Canada, Australia, and China, respectively. The upper part of the Mungok Formation is assigned to the late Tremadocian.

• 환경영향평가
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• 제14권6호
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• pp.403-413
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• 2005

The environmental conservation-targeted zoning in urban planning process has been functioned as securing a ecological core in urban green spaces management. Hence, the designation of conservation zones in land use planning is considered as a key task to achieve the sustainability of urban planning. The recently introduced pre-environmental review system for the proposed urban plan, by which the conservative measures for urban ecosystem and landscape are suggested in aspect of environmental impact mitigation, has played an active role in enhancing the environmental performance degraded by wide range of development pressure. This study is aimed at drawing out of objective criteria for designation of environmental conservation zones, which can be applied to urban planning establishment and also to environmental assessment process. To achieve this goal, the study adopted the following methods; pre-study review, analysis of existing official opinion statements released by the Ministry of Environment, contents analysis of related laws, and experts' panel discussions on the finally arranged criteria. The results of this research can be summarized as follows: First, the total criteria of 48 are drown out with categorizing into environment-ecological and socio-cultural sectosr. Second, the environment-ecological part is composed of 33 criteria such as vegetation, animal, geomorphology, watershed, environmental land suitability, and etc. Here, the Degree of Ecological Function, Degree of Environmental Land Suitability, and Vegetation Map are mainly utilized. Third, the 15 socio-cultural criteria relating to the history, social ecology and landscape have such components as forest around relics, Seo-won(school), castle, tomb, landmark, skyline, natural landscape, and etc. Forth, these individual criteria can be applied to designation of each conservation zones among total of 11 conservation areas(or districts).

• 한국주거학회논문집
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• 제4권2호
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• pp.73-83
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• 1993

Recently, large APT complexes are newly constructed in Taegu city and among them, large APT complexes aggegate densly espically in Weolsung and Jisan complexes of Dalsuh-gu and Susung-gu districts. The purpose of this thesis is to perform occupants' apprasials about residential environment on the housewifes residing at new constructed APT who seem tn have different apprasials on the residential environment by the zones. The results of the investigations are as follows. 1. House possessed type and house sire got elevated in comparison with them before shifting residence in respect to residential property and it was revealed they moved to short distance in the change of their lands. And most occupants could choose their houses by looting-out and there's some difference in the choice motive according to the zones. 2. As a result of studying the relation between demographic and residential properties, there were deep differe-nces in the Possessed house type before move, possessed house size after move, preferenti-al degree of house and move plan. 3. In the degree of satisfaction on residential environment, the result was high in the order of heating facilities, water-supply and draining facilities and lighting and was low in the order of room's size, interior decoration and soundproofin. According to zones, there was a great difference in the items of room's size, privacy, heating facilities, securi-ty from calamity, ventilation, convenience of traffic and school group and facilities for extracurricular activities and the degree of satisfaction was high in Jisan zone in othe items except for room's size and heating facilities. 4. In the tenants' apprasials on tile inside and outside spaces of the zones, important factors were "Cultural Institutions", "Green Areas", "Level of Welfare Facilities" and "Utility degree of welfare facilities" and in the classification of important factors according to the zones, the first and the third factors were changed each other. I think this is because they attached importance to somethings dissatisfied in present circumstances.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1593-1601
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• 2021

Oxide dispersion strengthening (ODS) tungsten alloys are highly desirable in irradiation applications. However, how to improve the properties of ODS-tungsten alloys efficiently has been worth studying for a long time. Here we report a nanostructuring approach that achieves W-La₂O₃ alloy with a high level of flexural strength and Vickers hardness at room temperature, which have the maximum value of 581 MPa and 703 Hv, respectively. This method named solution combustion synthesis (SCS) can generate 30 nm coating structures W-La₂O₃ composite powders by using Keggin-type structural polyoxometalates as raw materials in a fast and low-cost process. The composite powder can be fabricated to W-La₂O₃ alloy with an optimal microstructure of submicrometric W grains coexisting with nanometric oxide particles in the grain interior, and a stability interface structure of grain boundaries (GBs) by forming transition zones. The method can be used to prepare new ODS alloys with excellent properties in the future.