• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.2
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• pp.175-183
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• 2010

To understand the variation of macro benthos community according to the installation of structure and topographic placement in the shellfish farm on tidal flat, the practical example of the tidal shellfish growing area at Namsung-ri Goheung was observed. The results of the research for the field observation were summarized as follows. (1) The ground gradient of the shellfish farm was very flat below about $1^{\circ}$. The shellfish farm ground took the shape of $\sqcup$ from the shoreline to the place of 150 m seawards, and the shape of $\sqcap$ from there to the low tide line. During ebb tide, the $\sqcup$ shape ground stored the sea water, and the $\sqcap$ shape ground was supposed to act as the effect factor to leak slowly or to prevent the outflow. (2) The oyster shell bag or the type of riprap wall as the boundary in the shellfish farm was classified into five types. The air exposure time and flooding time were 181 and 434 minutes, respectively. (3) In the numerical experiment, the deep-sea water wave coming in the study area had 0.5 m of maximum wave height to show the very stable conditions and the wave direction pattern of S-direction was dominant at Naro great ridge, and SE, SSW and S-direction were distributed strongly around the shellfish farm. (4) By the grain size analysis, the sediment around tidal flat consisted of gravel 0.00~5.81(average 1.70)%, sand 14.15~18.39(average 13.23)%, silt 27.59~47.15(average 30.84)% and clay 35.79~55.73(average 36.19)%, and the sediment type was divided into (g)M(lightly gravelly mud), sM(sandy mud) and gM(gravelly mud) by Folk's diagram. (5) The macro benthos community survey conducted in this site in January, 2010 showed that 1 species of Mollusca, 8 species of Polychaeta and 2 species of Crustacea appeared, and 11 species occupying over 1% of total abundance were dominant.

• Journal of Environmental Science International
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• v.23 no.12
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• pp.2045-2056
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• 2014

In this study, pressure drop was measured in the pulse jet bag filter without venturi on which 16 numbers of filter bags (Ø$140{\times}850{\ell}$) are installed according to operation condition(filtration velocity, inlet dust concentration, pulse pressure, and pulse interval) using coke dust from steel mill. The obtained 180 pressure drop test data were used to predict pressure drop with multiple regression model so that pressure drop data can be used for effective operation condition and as basic data for economical design. The prediction results showed that when filtration velocity was increased by 1%, pressure drop was increased by 2.2% which indicated that filtration velocity among operation condition was attributed on the pressure drop the most. Pressure was dropped by 1.53% when pulse pressure was increased by 1% which also confirmed that pulse pressure was the major factor affecting on the pressure drop next to filtration velocity. Meanwhile, pressure drops were found increased by 0.3% and 0.37%, respectively when inlet dust concentration and pulse interval were increased by 1% implying that the effects of inlet dust concentration and pulse interval were less as compared with those changes of filtration velocity and pulse pressure. Therefore, the larger effect on the pressure drop the pulse jet bag filter was found in the order of filtration velocity($V_f$), pulse pressure($P_p$), inlet dust concentration($C_i$), pulse interval($P_i$). Also, the prediction result of filtration velocity, inlet dust concentration, pulse pressure, and pulse interval which showed the largest effect on the pressure drop indicated that stable operation can be executed with filtration velocity less than 1.5 m/min and inlet dust concentration less than $4g/m^3$. However, it was regarded that pulse pressure and pulse interval need to be adjusted when inlet dust concentration is higher than $4g/m^3$. When filtration velocity and pulse pressure were examined, operation was possible regardless of changes in pulse pressure if filtration velocity was at 1.5 m/min. If filtration velocity was increased to 2 m/min. operation would be possible only when pulse pressure was set at higher than $5.8kgf/cm^2$. Also, the prediction result of pressure drop with filtration velocity and pulse interval showed that operation with pulse interval less than 50 sec. should be carried out under filtration velocity at 1.5 m/min. While, pulse interval should be set at lower than 11 sec. if filtration velocity was set at 2 m/min. Under the conditions of filtration velocity lower than 1 m/min and high pulse pressure higher than $7kgf/cm^2$, though pressure drop would be less, in this case, economic feasibility would be low due to increased in installation and operation cost since scale of dust collection equipment becomes larger and life of filtration bag becomes shortened due to high pulse pressure.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.3
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• pp.157-164
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• 2016

In this study, researchers performed preliminary design and numerical analysis for a pilot-scale helium heating system intended to support full-scale construction for a sulfur-iodine (SI) cycle. The helium heat exchanger used a liquefied petroleum gas (LPG) combustor. Exhaust gas velocity at the heat exchanger outlet was approximately 40 m/s based on computational thermal and flow analysis. The maximum gas temperature was reached with six baffles in the design; lower gas temperatures were observed with four baffles. The amount of heat transfer was also higher with six baffles. Installation of additional baffles may reduce fuel costs because of the reduced LPG exhausted to the heat exchanger. However, additional baffles may also increase the pressure difference between the exchanger's inlet and outlet. Therefore, it is important to find the optimum number of baffles. Structural analysis, followed by thermal and flow analysis, indicated a 3.86 mm thermal expansion at the middle of the shell and tube type heat exchanger when both ends were supported. Structural analysis conditions included a helium flow rate of 3.729 mol/s and a helium outlet temperature of $910^{\circ}C$. An exhaust gas temperature of $1300^{\circ}C$ and an exhaust gas rate of 52 g/s were confirmed to achieve the helium outlet temperature of $910^{\circ}C$ with an exchanger inlet temperature of $135^{\circ}C$ in an LPG-fueled helium heating system.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.2
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• pp.197-206
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• 2023

Recently, the international community, including the International Maritime Organization (IMO), has strengthened regulations on air pollution emissions of ships, and eco-friendly ships are actively being developed to reduce exhaust gas emissions. Among them, rotor sail (RS), a wind-assisted ship propulsion system, is attracting attention again. RS is a cylindrical device installed on the ship deck, that generates hydrodynamic lift using a magnus effect. This is a next generation eco-friendly auxiliary propulsion technology, and Enercon company, which developed RS-applied ships, announced that fuel savings of more than 30% are possible. In this study, optimal installation conditions such as RS spacing and arrangement type were selected when multiple RSs were installed on ships. AR=5.1, SR=1.0, and D_e/D was fixed at 2.0 according to the RS arrangement, and the wind direction was considered only for the unidirectional +y-axis. Regarding arrangement conditions, five conditions were set at 3D intervals in the +x-axis direction from 3D to 15D and five conditions in the +y-axis direction from 5D to 25D. C_L, C_D and aerodynamic efficiency (C_L/C_D) were compared according to the square(□) and diamond(◇) shape arrangements. Consequently, the effect of RS on the longitudinal distance was not significantly different. However, in the case of RS flow characteristics according to the transverse distance, the interaction effect of RS was the greatest when the two RSs almost matched the wind direction. In the case of the RS flow characteristics according to the arrangement, notably, when the wind blew in the forward (0°) direction, the diamond (◇) arrangement was least affected by the backward flow between RSs.

• The Journal of Engineering Geology
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• v.29 no.1
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• pp.51-68
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• 2019

This study performs to evaluate adaptability of seashore filtering type seawater-intake which adapts dua1 filter well alternative for direct seawater-intake. This study varies filter condition of seashore free surface aquifer which is composed of sand layer then installs real size dual filter well and single filter well to evaluate water permeability and proper pumping amount according to filter condition. According to result of step aquifer test, it is analysed that 110.3% synergy effect of water permeability coefficient is happened compare to single filter since dual filter well has better improvement. dual filter has higher water permeability coefficient compare to same pumping amount, this means dual filter has more improved water permeability than single filter. According to analysis result of continuous aquifer test, it is evaluated that dual filter well (SD1200) has higher water permeability than single filter well (SS800) by analysis of water permeability coefficient using monitoring well and gauging well, it is also analysed dual filter has 110.7% synergy effect of water permeability coefficient. As a evaluation result of pumping amount according to analysis of water level dropping rate, it is analysed that dual filter well increased 122.8% pumping amount compare to single filter well when water level dropping is 2.0 m. As a result of calculating proper pumping amount using water level dropping rate, it is analysed that dual filter well shows 136.0% higher pumping amount compare to single filter well. It is evaluated that proper pumping amount has 122.8~160% improvement compare to single filter, pumping amount improvement rate is 139.6% compare to averaged single filter. In other words, about 40% water intake efficiency can be improved by just installation of dual filter compare to normal well. Proper pumping amount of dual filter well using inflection point is 2843.3 L/min and it is evaluated that daily seawater intake amount is about $4,100m^3/day$ (${\fallingdotseq}4094.3m^3/day$) in one hole of dual filter well. Since it is possible to intake plenty of water in one hole, higher adaptability is anticipated. In case of intaking seawater using dual filter well, no worries regarding damages on facilities caused by natural disaster such as severe weather or typhoon, improvement of pollution is anticipated due to seashore sand layer acts like filter. Therefore, It can be alternative of environmental issue for existing seawater intake technique, can save maintenance expenses related to installation fee or damages and has excellent adaptability in economic aspect. The result of this study will be utilized as a basic data of site demonstration test for adaptation of riverside filtered water of upcoming dual filter well and this study is also anticipated to present standard of well design and construction related to riverside filter and seashore filter technique.

• FLOWER RESEARCH JOURNAL
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• v.18 no.3
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• pp.186-192
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• 2010

An infrared heating system, installed in a small venlo-type glasshouse ($280m^2$) in Gyeongsang National University, Jinju, Korea, was used to investigate its heating effect with potted Phalaenopsis, Schefflera arboricola 'Hongkong', Ficus elastica 'Variegata', and Rosa hybrida 'Yellow King' as the test plants. Temperature changes in test plants with the system turned 'On' and 'Off' were measured by using an infrared camera and the consumption of electricity by this infrared heating system was measured and analyzed. In potted Phalaenopsis, when the set air temperature of the greenhouse was $18^{\circ}C$, temperature of leaves and the growing medium were $22.8{\sim}27^{\circ}C$ and $21.3{\sim}24.3^{\circ}C$, respectively. In such tall plants as Schefflera arboricola 'Hongkong' and Ficus elastica 'Variegata', the upper part showed the highest temperature of 24.0 and $26.9^{\circ}C$, respectively. From the results of temperature change measurements, the plant temperatures were near or above the set point temperatures with some fluctuations depending on the position or distance from the infrared heating system. When air temperature between night and dawn dropped sharply, plant temperatures were maintained close to the set temperature ($18^{\circ}C$). There was a significant difference between 'On' and 'Off' states of the infrared heating system in average temperatures of root zone and leaf: 21.8 and $17.8^{\circ}C$ with the system 'On' and 20.4 and $15.5^{\circ}C$ with the system 'Off', respectively, in a cut rose Rosa hybrida 'Yellow King'. The heating load was about $24,850{\sim}35,830kcal{\cdot}h^{-1}$, which comes to about 27,000~40,000 won in Korean currency when calculated in terms of the cost of heating by a hot water heating system heated by petroleum. The cost for heating by the infrared heating system was about 35% of that of a hot water heating system. With the infrared heating system, the air temperature during the night was maintained slightly lower than the set point air temperature, probably due to the lack of air tightness of the glasshouse. Therefore, glasshouses with an infrared heating system requires further investigation including the installation space of the heat-emitting units, temperature sensor positions, and convection.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.2
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• pp.93-104
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• 2002

A field survey and experiment was conducted from 1996 to 1998 to develop rational technology for turfgrass vegetation of runway side of Incheon International Airport on the reclaimed tidal land in Young-Jong Island. Backfill of the experimental site was finished on August 1995. The experimental site was 8 ha located in the middle of the construction place for the main parking lot in front of the terminal building construction. The experimental field was drained by main open ditch, and divided three main plots, no subsurface tile drain, subsurface tile drain spacing with 22.5m, and with 45 m, respectively. The 17 sub plots were designed to test the effect of soil covering with red earth loam by 5 cm and 20 cm depth, application of chemical compound fertilizers and livestock manures, dressing of artifical soils and hydrophylic soil conditioners. The tested turfgrasses were three transplanting indigenous turfgrasses, Zoysia koreana, Zoysia sinica and Zoysia japonica, and two hydroseeding mixed exotic turgrasses, cool type I(tall fescue 30%, kentucky blue grass 40%, perenial ryegrass 30%), and cool type II(tall fescue 40%, perenial ryegrass 20%, fine fescue 20%, alkaligrass 20%). The soil backfilled with dredged seasand was sand textured with high salt concentration and low fertility. The soil showed high pH, low organic matter and low available phophate contents. The percolation rate was fast with high hydraulic conductivity. Desalinization was fast after installation of the main open drainage system. No subsurface tile drainage effect was found showing little difference in turfgrass growth. The covering and visual growth of turfgrasses were the best in the 20-cm soil covering with compound fertilizer treatment. The covering and visual growth of turfgrasses were satisfactory in the 5 cm soil covering with compound fertilizer treatment and with livestock manure treatments. The hydrophillic soil conditioner treatments were effective but expensive at present. The coverage and visual quality of turfgrasses were good for Zoysia koreana and Zoysia japonica. The coverages of turfgrasses by the hydroseeding with the mixed exotic turfgrasses were less than transplanting of native turfgrasses. In conclusion, for the runway side vegetation purposes, the subsurface tile drainage might not necessary as main open ditch drainage be sufficient due to fast percolation rate of the backfilled dredged seasand. The 5 cm soil covering with red earth might be sufficient for the runway side, but the 20 cm soil covering might be necessary for the runway side where high density of turfgrass coverage was necessary to protect from the airplance air blow.

• Journal of architectural history
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• v.19 no.3
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• pp.7-29
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• 2010

The form of the Wangheungsa Temple's wooden pagoda site is that of the traditional form of the wooden pagodas constructed during the Baekjae Period. Likewise, it is an important ruin for conducting research on the form and type of the wooden pagodas constructed during the Baekjae Period. In particular, the method used for the installation of the central pillar's cornerstone is a new technique. The purpose of this research is to restore the ruin of the Wangheungsa Temple's wooden pagoda of the Baekjae Period that remains at the Wangheungsa Temple's wooden pagoda site. Until now, research conducted on the wooden pagoda took place mostly centered on the Hwangryongsa Temple's wooden pagoda. Meanwhile, the reality concerning Baekjae's wooden pagoda is one in which there were not many parallel cases pertain to the design for restoration. This research paper wants to conduct academic examination of the Wangheungsa Temple's wooden pagoda to organize the intention of design and design process in a simple manner. This research included review of the Baekjae Period's wooden pagoda related ruins and the review of the existing wooden pagoda ruin to analyze the wooden pagoda construction technique of the era. Then, current status of the Wangheungsa Temple's wooden pagoda site is identified to define the characteristics of the wooden pagoda, and to set up the layout format and the measure to estimate the size of the wooden pagoda in order to design each part. Ultimately, techniques and formats used for the restoration of the wooden pagoda were aligned with the wooden pagoda of the Baekjae Period. Basically, conditions that can be traced from the current status of the Wangheungsa Temple site excavation using the primary standards as the standard. Wangheungsa Temple's wooden pagoda was designed into the wooden pagoda of the Baekjae's prosperity phase. The plane was formed into $3{\times}3$ compartments to design into three tier pagoda. The height was decided by factoring in the distance between the East-West corridors, size of the compartment in the middle, and the view that is visible from above the terrace when entering into the waterway. Basically, the origin of the wooden structure format is based on the Goguryeo style, but also the linkage with China's southern regional styles and Japan's ancient wooden pagoda methods was factored in. As for the format of the central pillar, it looks as if the column that was erected after digging the ground was used when setting up the columns in the beginning. During the actual construction work of the wooden pagoda, central pillar looks as if it was erected by setting up the cornerstone on the ground. The reason that the reclaimed part of pillar that use the underground central cornerstone as the support was not utilized, was because the Eccentric Load of the central pillar's cornerstone was factored in the state of the layers of soil piled up one layer at a time that is repeated with the yellow clay and sandy clay and the yellow clay that were formed separately with the $80cm{\times}80cm$ angle at the upper part of the central pillar's cornerstone was factored in as well. Thus, it was presumed that the central pillar was erected in the actual design using the ground style format. It is possible to presume the cases in which the reclaimed part of pillar were used when constructed for the first time, but in which central pillar was installed later on, after the supplementary materials of the underground column is corroded. In this case, however, technique in which soil is piled up one layer at a time to lay down the foundation of a building structure cannot be the method used in that period, and the reclamation cannot fill up using the $80cm{\times}80cm$ angle. Thus, it was presumed that the layers of soil for building structure's foundation was solidified properly on top of the central pillar's cornerstone when the first wooden pagoda construction work was taking place, and that the ground style central pillar was erected on its upper part by placing the cornerstone once again. Wangheungsa Temple's wooden pagoda is significant from the structure development aspect of the Korean wooden pagodas along with the Hwangryongsa Temple's wooden pagoda. Wangheungsa Temple's wooden pagoda construction technique which was developed during the prosperity phase of the Baekjae Period is presumed to have served as a role model for the construction of the Iksan Mireuksa Temple's wooden pagoda and Hwangryongsa Temple's wooden pagoda. With the plan to complement the work further by excavating more, the basic wooden pagoda model was set up for this research. Wangheungsa Temple's wooden pagoda was constructed as at the Baekjae Kingdom wide initiative, and it was the starting point for the construction of superb pagoda using state of the art construction techniques of the era during the Baekjae's prosperous years, amidst the utmost interest of all the Baekjae populace. Starting out from its inherent nature of enshrining Sakyamuni's ashes, it served as the model that represented the unity of all the Baekjae populace and the spirit of the Baekjae people. It interpreted these in the most mature manner on the Korean peninsula at the time.

• The Korean Journal of Health Service Management
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• v.2 no.1
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• pp.105-124
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• 2008

The purpose of this research is to provide the data base for the activation of Quality Improvement operation through investigating the status of Quality Improvement operation, and finding out factors influencing on the goal-orientation of QI performers in the medical centers of more than one hundred beds where are practicing Quality Improvement operation. In order to reach the purpose, document study was carried out grounded on the proceeding researches and formulated statistical data in relation with the status of Quality Improvement performers, and proof study was carried out through questionnaire survey. The subjects of the survey were the Quality Improvement performers working in seventy three medical centers in Pusan-Gyeongnam, Daegu-Gyeongbuk, and Ulsan. Among eighty three Quality Improvement performers, fifty, five were questionnaire surveyed, on the result of which Reliability Analysis, Factor Analysis, and Multiple Regression Analysis were made, using statistical program. The the results of the proof analysis on this research are as follows. First, in the factors influencing the devoting to goal pursuit of QI performers, organization-goal contribution(0.44) had significant positive effects, while organization conflict(-0.25) had significant negative effects. In other words, the higher the organization-goal contribution was, the higher the devoting to goal pursuit was, while the less the organization conflict was, the higher the devoting to goal pursuit was, which was statistically significant.(p<0.05). Second, in the aspect of goal performance types of QI performers, the process-centered type showed high level of the devoting to goal pursuit, which was statistically significant.(p<0.05). Third, in the aspect of QI performance degree, the higher the devoting to goal pursuit was, the higher the QI performance degree was, which was statistically significant.(p<0.05). In addition, the performers who perceived their workplaces organic structure showed much higher QI performance degree, which statistically significant.(p<0.05). Generalizing the results of this research, it is possible to offer a few suggestions as follows. First, as the competition among the medical centers is more severe recently owing to medical center evaluation system, medical centers are practicing various Quality Improvement operation in all of medical services such as clinical performance and management performance, to reach the purpose of both cost-cutting and medical quality improvement. Thus in order to practice Quality Improvement operation more efficiently in medical centers, it is essential to nuke use of problem-solving methods and statistical members. This as the willingness of chief executives and positive attitude and recognition of organization members. This requires the installation of divisions in charge and disposition of persons in charge, not to speak of persistent training of Quality Improvement. Second, the divisions in charge of QI carry out Quality Improvement operation at the medical center level, and take the role of generalizing and adjusting QI performances of various departments. Owing to this role, the division in charge of QI is considered indispensable organization in the QI operation of medical centers along with medical QI committee, while it contributes to the government's goal of reducing quality level gaps among medical centers. Therefore it is necessary for government and QI organizations to give institutional support and resources for the sake of QI operation of medical centers, besides to supply systematic trainning and informations to the divisions and persons in charge of QI. Third, it is certain that disposition of persons in charge should be determined in view of the scale and the scope of QI operation in medical centers.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.2
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• pp.42-54
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• 2014

This study was conducted to identify landscaping elements such as location, situation and feng shui included in the spatiality of Jangseong Pilmaseowon and to interpret aesthetic features of visual-perceptual spatial composition according to its arrangement. As it is shown in 'Pilamseowon', 'Pilbongseowon', and 'Gimhaseoseowon' appearing in antique maps, the awareness considering 'Pilam' as 'Pilbong' and 'Gimhaseo' was revealed. Mountain Pilamsan[Mountain Munpilsan] which is the location of seowon and Pilam(Brush-shaped rock) is the core of establishment of location identity of Pilamseowon and the symbol of Haseo Kim In-hu, which shows that they are deeply related to Ingeoljiryeong(人傑地靈: 'a place derives reflected glory from an illustrious human') based on connection. Pilamseowon shows locational characteristics of living in stream(溪居) facing panoramic 'jeungsan field' without Ansan(案山). Based on the teachings of Neo-Confucianism, Village Maekdong which is the birth place of Haseo, Pilam, seowon geomancy considering the Danbonghamseo-type(丹鳳含書形) geographical shape, formative reflection, Pilmaseowon and structures revealed in building naming more clearly show symbolic landscaping features resulting from 'theory of 'Heaven-Man Unity'(天人合一)' representing the union of nature and haman, than other seowons. The maximization of centrality through connected yards constructed with the 'jeondang hujae(前堂後齋)' arrangement in the order of Whakyeon-lu, Chenogjeol-dang, Jindeak-jae or Sungui-jae, and Woodong-sa is a unique feature of spatial frame of Pilmaseowon. In addition, it reveals the centrality reinforced with 'the move of inner center through arrangement of Kyeongjang-kag and Kyesengbi inside 'YuSik(遊息)' space and religious space' and the landscaping arrangement of Pilmaseowon from installation and device for reinforcement of territoriality. Moreover, it was found that orders and aesthetic features based on Neo-Confucianism were logically realized in the formation of Pilmaseowon with visual and compositional landscaping arrangement such as 'reinforcement of view centrality through composition of windows and doors', 'securement of visual transparency through framing and duplication', and 'realization of hierarchy through height of jaesil toenmaru'. The meaning system and spatial or visual aesthetic features of Pilmaseowon newly arranged and interpreted through landscaping recomposition is not a coincidental but inevitable result. It is another resource basis and an element that can improve the internal exuberance of Pilamseowon. This landscaping reading study is expected to improve the understanding of landscapes of Pilmaseowon and elevate the sensibility of unrevealed cultural landscapes.