• Journal of Energy Engineering
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• v.27 no.3
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• pp.1-9
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• 2018

In this study, the outdoor evaluation test was performed to characterize the highly-reflective artificial grass to be used for bifacial photovoltaic (PV) power generation system. The 60-cell n-type Si monofacial and bifacial PV modules were employed, where two types of bifacial modules were equipped with split-type and box-type junction boxes, respectively. The results showed that the split-type junction box improved the rear-side power production and thus energy yield of bifacial module compared to the box-type junction box causing the shadow effect. Highly-reflective artificial grass achieved relatively high albedo of 0.18, and excellent bifacial gain of 33%, compared to conventional artificial grass with an albedo of 0.14-0.15, and bifacial gain of 29-30%.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.12
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• pp.821-827
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• 2012

Air drying is a technology to dry sludge at the ejector and multi cyclone as intaking and blowing air from outside. So, this technology has a weak point that operating fluctuation is large according to an outside conditions as well as energy consumption is also large due to open loop structure. This is to develop the closed-loop air drying system to be built the dehumidifier consisted of condenser, cooler and compressor at rear side of separator of air dryer, as a way to solve some problem. Air is circulation by the method of blowing-drying-dehumidifying-blowing within this system. It is analyzed that an air circulated at closed-loop air drying equipment contains the energy of 50% more compared with open-loop air drying and is operated regularly because of quality maintenance of air to dry sludge. And also it is analyzed that the cost of drying sludge of 1 ton by closed-loop air drying equipment is lower about 35% than conventional equipment. Therefore, this is evaluated by useful drying technology to face an unexpected climatic conditions due to regular operation as well as low energy consumption.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.1
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• pp.81-96
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• 2007

Nonlinear shoaling characteristics over surf zone are numerically investigated based on spatially averaged NavierStokes equation. We also test the validity of gradient model for turbulent stresses due to wave breaking using the data acquainted during SUPERTANK LABORATORY DATA COLLECTION PROJECT(Krauss et al., 1992). It turns out that the characteristics length scale of breaking induced current is not negligible, which firmly stands against ever popular gradient model, ${\kappa}-{\varepsilon}$ model, but favors Large Eddy Simulation with finer grid. Based on these observations, we model the residual stress of spatially averaged NavierStokes equation after Lagrangian Dynamic Smagorinsky(Meneveau et al., 1996). We numerically integrate newly proposed wave equations using SPH with Gaussian kernel function. Severely deformed water surface profile, free falling water particle, queuing splash after landing of water particle on the free surface and wave finger due to structured vortex on rear side of wave crest(Narayanaswamy and Dalrymple, 2002) are successfully duplicated in the numerical simulation of wave propagation over uniform slope beach, which so far have been regarded very difficult features to mimic in the computational fluid mechanics.

• Journal of architectural history
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• v.3 no.1
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• pp.83-99
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• 1994

Ch'ang-Ts'al-Ts'un is a rural Village near Lung-jing City in Yen-pien Korean Autonomous Province of China. It was formed about 100 years ago by Korean Immigrants and has been developed maintaing the characteristics of traditional Korean architecture. Therefore investigating the spatial structure of this village is a meanigful work to confirm and explore one branch of Korean architecture. This study aims at analyzing the spatial structure of the village using direct data collected from the field work and indirect data from books and maps. The field work consists of on-the-site survey of the village layout, interviews of residents, observation notes and photography. Ch'ang-Ts'ai-Ts'un is located 360-370 m high above the sea level and at the side of a long valley. A river flows in the middle of the valley and relatively flat arable land exists at the both sides of the river. The location of the village related to the surrounding river and mountains suggests that the site of the village was chosen according to Feng-Shui, Chinese and Korean traditional architectural theory. The main direction of the house layouts is South-western. The village has been growing gradually until today. Therefore it is meaningful to make the village layout before Liberation(1946 A.D.) because the characteristics of Korean architecture prevailed more in that period. The area of the previous village is limited to the west side of the creek. New houses were later added to the east of the creek, forming a 'New Village'. Previously the village was composed of 3 small villages: Up, Middle and Down. Also the main access roads connecting the village with the neighboring villages were penetrating the village transversely. Presently the main access road comes to the village longitudinally from the main highway located in front of the village. The retrospective layout shows the existence of well-formed Territory, Places and Axes, thus suggesting a coherent Micro-cosmos. The boundary of imaginery territory perceived by present residents could be defined by linking conspicous outside places sorrounding the village such as Five-mountains, Front-mountain, Shin-dong village, Standing-rock, Rear-mountain and Myong-dong village. Inside the territory there are also the important places such as Bus-stop, Memorial tower of patriots, Road-maitenance building and the village itself. And inside it 5 transverse and 1 longitudinal axes exist in the form of river, roads and mountains. The perceived spatial structure of the village formed by Places, Axes and Territory is geometrical and well-balanced and suggests this village is fit for human settlement. The administrative area of the village is about 738 ha, 27 % of which is cultivated land and the rest is mountain area. Initially the village and surrounndings were covered with natural forest But the trees have been gradually cut down for building and warning houses, resulting in the present barren and artificial landscape with bare mountains and cultivated land. At present the area of the village occupied by houses is wedge-shaped, 600 m wide and 220 m deep in its maximum. The total area of the village is $122,175m^{2}$. The area and the rate of each sub-division arc as follow. 116 house-lots $91,465m^{2}$ (74.9 %) Land for public buildings and shops $2,980m^{2}$ (2.4 %) Roads $17,106m^{2}$ (14.0 %) Creek $1,356m^{2}$ (1.1 %) Vacant spaces and others $9,268m^{2}$ (7.6 %) TOTAL $122,175m^{2}$ (100.0 %) Each lot is fenced around with vertical wooden pannels 1.5-1.8 m high and each house is located to the backside of the lot. The open space of a lot is sub-divided into three areas using the same wooden fence: Front yard, Back yard and Access area. Front and back yards are generally used for crop-cultivation, the custom of which is rare in Korea. The number of lots is 116 and the average size of area is $694.7m^{2}$. Outdoor spaces in the village such as roads, vacant spaces, front yard of the cultural hall, front yard of shops and spacse around the creek are good 'behavioral settings' frequently used by residents for play, chatting, drinking and movie-watching. The road system of the village is net-shaped, having T-junctions in intersections. The road could be graded to 4 categories according to their functions: Access roads, Inner trunk roads, Connecting roads and Culs-de-sac. The total length of the road inside the village is 3,709 m and the average width is 4.6 m. The main direction of the road in the village is NNE-SSE and ESE-WNW, crossing with right angles. Conclusively, the spatial structure of Ch'ang-Ts'ai-Ts'un village consists of various components in different dimensions and these components form a coherent structure in each dimension. Therefore the village has a proper spatial structure meaningful and appropriate for human living.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.3
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• pp.85-97
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• 2010

This research studied the location and the spatial composition of Pihyang-jeong zone. Pihyang-jeong is regarded as one of the five great pavilions in Chollabuk-do. Located in Taein-myeon of Jeongeup-si, Pihyang-jeong is also called as 'the number one pavilion in Honam area'. 1. There is no record regarding the first construction of Pihyang-jeong. There is only transmitting by word of mouth that the scholar Choi Chi-won had an excursion to here and composed some poetry during the age of King Heon-gang of Shilla dynasty. However, there are records that Lee Ji-gweng had expanded the humble structure in 1618, Park Sung-go repaired it in 1664 and Yoo Geun repaired it again in 1715. 2. The location of Pihyang-jeong is 'high in north and low in south' and typical 'mountain in rear and water in front'. It has Seong-hwang Mountain(189m) in the north, Hang-ga Mountain(106m) in the south, Tae Mountain(33m) in the south and an open field in the northwest. 3. The spatial composition around Pihyang-jeong is as following. Pihyang-jeong faces 'Hayeonji'(the lower side lotus pond) in the south-south-west direction. 4. The buildings around Pihyang-jeong are; Pihyang-jeong, which was the pavilion of the government official not directly in charge of government office, Hambyeok-lu in the Hayeonji and the facility for the caretaker. Pihyang-jeong is a rectangular building with double eaves and hipped-and-gabled roof. It has five rooms in the front and four rooms in the side. Hambyeok-lu had been first built in 1918 as two-storey wooden pavilion with dancheong, traditional multicolored paintwork on wooden buildings. Then it was modified into rectangular single-storey pavilion with hipped-and-gabled roof and five rooms in 1971. In 2010, it was rebuilt as a hexagonal pavilion; therefore, the present shape is completely different one from the original shape. 5. The scenic features around Pihyang-jeong are as following. There are 21 stone monuments in Pihyang-jeong zone. The fence surrounding Pihyang-jeong is a traditional Korean style crude stone fence. There are three gates in three-gates-style, each gate made with two posts and one 'matbae'(gabled) roof. Also, a stepping stone for mounting/dismounting was found in the east of Pihyang-jeong outer perimeter. 6. The water scenic feature around Pihyang-jeong is a representative case of drawing in the water from the natural pond nearby government office and building a pavilion around the water. 7. The planting around Pihyang-jeong is as following. There are Zelkova trees in the boundary perimeter. In the southern small park, there are Zelkova trees, Crape-myrtie trees, Bushy young pine trees, Pine trees, Satuki, Purple azalea and Grass field. Around Hambyeok-lu in the Ha-yeonji, Elm trees, Zelkova trees and Pine trees are growing in good condition.

• Journal of the Korean Society of Radiology
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• v.12 no.7
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• pp.895-908
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• 2018

As modern science is developed and advanced, examination and number of times using radiation are increasing daily. General diagnostic X-ray generator is installed on stationary form, But X-ray generator was developed because patient who is in the intensive care unit, operation room, emergency room can not move to general x-ray room. What we examine patient by x-ray generator is certainly necessary, So patient exposure is inevitable. but reducing radiation exposure is highly important matter about radiation technology, guardian, patient in the same hospital room, nurse etc. For this reason, rule regarding safety control of diagnostic x-ray generator revised for radiation worker, patient and protector proclaim that mobile diagnostic x-ray shield must placed in case of examine different location excluding operation room, emergency room, intensive care unit. But, radiogical technologist is having a lot of difficulties to examine with mobile x-ray generator, diagnostic x-ray shield partition, image plate and lead apron. So, when we use x-ray generator, we manufacture shield tools can be attached to the mobile x-ray generator On behalf of x-ray shield partition and conduct analysis and in comparison to part of body and distribution of dose rate and find way to reduce radiation exposure through distribution of dose rate of patient within the radiogical technologist, medical team. Mobile x-ray generator aimed at SHIMADZU inc. R-20, We manufactured equipment for shielding x-ray scattered x-ray by installing shielding wall from side to side based on support beam on the mobile x-ray generator. Shielding wall when moving can be folded and designed to expand when examine. Experiment measured five times in each by an angle for dose rate of eyes, thyroid, breast, abdomen and gonad on exposure condition of upper and lower extremity, chest, abdomen which is examined many times by mobile x-ray generator. We used dosimeter RSM-100 made by IJRAD and measured a horizontal dose rate by body part. The result of an experiment, shielding decreasing rate of the front and the rear showed 77 ~ 98.7%. Therefore using self-production shielding wall reduce scattered x-ray occurrence rate and confirm can decrease exposure dose consequently. Therefore, through this study, reduction result which is used shielding wall of self-production will be a role of shielding optimization and it could be answer about reduction of medical exposure recommended by ICRP 103.

• Journal of the Korean Society of Costume
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• v.5
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• pp.41-63
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• 1981

The mural portraits of the ancient Dukheungri tombs are very important for the study of our traditional costume because the tomb contains a stone. with the in-scription of the date of its erection, 408 A.D. and the name, and official status of the buried. The costumes shown in the mural paintings will be the basis on which historical research can be made concerning costumes before and after 400 A. D. The costume in the mural paintings is classified into five different categories; You (jacket), Po (overcoat), Go (trousers), Sang (skirt), and Gwan (hat). Comparing these categories with those of other mural paintings lead us to the following conclusions. 1. The length of the You (jacket) reaches below the buttocks and the sleeves are narrow. The edges of the sleeves are decorated with stripes. The You (jacket) over-laps on the right, center, and left sides, and there are many Jikryong (V-collar) and Danryong (rounded collar) styles, but it has a similar tendency to others of the Pyongyang area which exhibit many foreign influences. In a departure from tradition. the belts on the men's You (jackets) have only 3 knots in the front, with the back having more knots than the front. The belts of the women's You (jacket) seem to have had a band or button for fastening. We must re-evaluate the assumption that the You (jacket) and Go (trousers) of the northern peoples had the common characters of a belted You (jacket) and Po (over-coat) and that the Gorum originated from the Goryo or Unified Silla dynasty. The outside of the sleeves are longer and more to the side than the inner garment (underwear) so that the sleeves of the inner garment frequently overlapped the outer dress. The above mentioned facts have lead to the discovery of the "Hansam," "Tosi" and "Geodoolgi." 2. The Po (overcoat) was used only by the upperclasses and differs from those found in other mural tombs. The Po (overcoat) of the noble on the tomb mural is centered with an overlapping Jikryong (V-collar) while the other Po (overcoats) of the upperclasses are characterized by an overlap on the left, a Danryong (rounded collar) with two types of sleeves (wide and narrow). Foreign influences and traditional influences coexist in Po (overcoat). Belts have frontal knots without exceptions. The facts that the belts on the You (jackets) are on the front and the belts on the Po (overcoats) are on the back must be reexamined. 3. Go (trousers) is usually narrow, being wider in the rear and narrower below the knees. They were used by hunters on the back of horses with similar Go (trousers) from the Noinwoowha tombs being typical of the northern peoples. 4. Sang (skirts) are pleated as commonly seen in the Goguryo murals. The size of the pleat is varied, each pleat being characteristically wider and having different colors. Same types of pleat are discovered in Central Asia and China. It is uncertain whether the pleat of Goguryo was originated in Central Asia and China or only interrelated with those of the areas. 5. There are three kinds of Gwan (hats); Nagwan, Chuck, and Heukgun. Nag-wan was worn by the dead lords and their close relations. Chuck has three cone shaped horns. Heukgun was worn by military bandmen and horsemen. There are two kinds of hair styles. The up-style was used by the upperclass people closely related to lords, and other people used the Pungimoung hair style. The hair styles of the men and women are characterized by the Pungimoung style. which is a Chinese influence, but still retain their originality. The costume has a similar tendency from those from Yaksuri mural tombs, Anak No. 2 and Anak No. 3. We need to reexamine the costumes from $4{\sim}5$ century murals according to the Dukheungri murals. The costumes of Goguryo share many common factors with those of Western Asia, Central Asia and Ancient China (Han). It seems due to the cultural exchanges among the Northern peoples, the Western and Central Asians, and the Ancient Chinese. It may have resulted from the structural identity or morphological identity of the peoples, or their common social and natural environments and life styles. It will be very valuable to study the costumes of Japan, China, and Korea to find out the common factors. It is only regretful that the study is not based on direct observations but reported information made by 77 persons, because Dukheungri is an off-limits area to us.

• Korean Journal of Applied Biomechanics
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• v.15 no.2
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• pp.11-20
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• 2005

This study has a purpose on contributing to apprehend safe and right way to stop to the inline skate beginners and to the instructors who teaches line skating on the basis for the result of the kinematical analysis on Heel brake stop movement of the inline skate, focusing on the displacement on COG, angle displacement of ankle joint, angle displacement of knee joint, angle displacement of hip joint, using a 3D image method by DLT. To achieve this goal, we analysed the kinematical factor of the 3 well-trained inline skating instructors and obtained the following results. 1. During the movement of heel-brake stop, when strong power was given to a stable and balanced stop and the lower limbs, if the physical centroid is lowered the stability increases, and if it is placed high from the base surface, as the stability decreases compared to the case of low physical centroid, we should make a stop by placing a physical centroid in the base surface and lowering the hight of physical centroid. 2. To make a stable and balanced stop and to provide a strong power to the lower limbs, it is advisable to make a stop by decreasing an angle displacement of ankle joint during a "down" movement. In case of the left ankle joint, in all events and phases the dorsiflexion angle showed a decrease. Nevertheless, in the case of the right ankle joint, the dorsiflexion angle shows an increase after a slight decrease. The dorsiflexion angle displacement of ankle joint can be diminished because of the brake pad of the rear axis frame of the right side inline skate by raising a toe, but cannot be more decreased if certain degree of an angle is made by a brake pad touching a ground surface. To provide a power to a brake pad, it is recommended to place a power by lowering a posture making the dorsiflexion angle of the left ankle joint relatively smaller than that of the right ankle. 3. To make a stable and balanced stop and to add a power to a brake pad, the power must be given to the lower limbs in lowering the hight of physical centroid. For this, it is recommended to make a down movement by decreasing the flexion angle of a knee joint and it is necessary to make a down movement by a regular decrease of the angle displacement of knee joint rather than a swift down movement in every event and phase. 4. The right angle displacement of hip joint is made by lowering vertically the hight of physical centroid as leaning slightly forward. If too narrow angle displacement of hip joint is made by leaning forward too much, the balance is lost during the stop by placing the center in front. To make a stable and balance stop and to place a strong power to the lower limbs, it is recommendable to make a narrow angle by lower the hip joint angle. However, excessive leaning of the upper body to make the angle too narrow, can cause an instable stop and loss of physical centroid. After this study, it is considered to assist the kinematical understanding during the heel brake stop movement of the inline skate, and, to present basic data in learning a method of stable and balanced stop for the inline skating beginners or for the inline skate instructors in the present situation of the complete absence of the study in inline skating.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5
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• pp.113-121
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• 2010

Shumi-sen(須彌山), built by Nohjagong(路子工) in the southern garden of the Palace Garden during the Asuka Period, is understood as being Sumeru based on an Indian perspective of the theory of the origin of universe. It is also viewed as Mt. Myogoh from a Chinese Buddhist worldview. It is thought to be a type of assembled stone structure with Poong-ryoon (風輪)-Su-ryoon(水輪)-Geum-ryoon(金輪)-Ji-ryoon(地輪) carved into each of the 4 stone pieces. These building shapes are thought to have been utilized as stone for exterior construction as opposed to those structures built during the Shilla Period of China and Korea. Aside from Nohjagong's record of Shumi-sen, most of the records from Japan's period of the time suggest that Shumi-sen was an important element that played a role in the scenery of the seasonal outdoor gardens. It is also thought, from the sentences and expressions surrounding the records, that a combination of the seasonal sceneries was utilized centered on Shumi-sen, and that they were all used during festival events. From a perspective of analysis and interpretation dependent on the limited literature and on observation, it cannot be verified whether the Mt. Sumeru Stone(須彌山石) excavated from the Stone God Ruins is the same Shumi-sen that Nohjagong built along with Okyo(吳橋), but it is thought that the 'Shumi-sen type stone structure' that was later built repeatedly as part of the palace garden facilities is identical to the Shumi-sen built at the Imperial Palace's southern garden, or at least a re-built structure based on the Shumi-sen that Nohjagong built with stones and ponds used to create the foundation. Thus, Shumi-sen that Nohjagong supposedly built along with Okyo is suspected to be a figurative rock arrangement and, at the same time, a miniaturized scenic rock arrangement(縮景樹石) that maximized the shape of Buddhism's Shumi-sen. On the other hand, the surface pattern on Mt. Sumeru Stone is very similar to the multi -layers of mountainous pattern icons expressed in the patterns of the Great Golden Incense Burner(百濟金銅大香爐) or Mountain-Water Scenery Sculptural Brick(山水山景紋?) that were built during the Baekjae pcriod aod the rear side of Hwalsuk-jebul Basal Byungipsang(滑石諸佛菩薩竝立像); it is suspected that similar patterns would have been used if patterns were made on Shumi-sen that Nohjagong built. Also in consideration of the physical theory of MI. Sumeru Stone, the Siphon theory of using a pressure difference in water level was applied to the fountain facilities of Mt. Sumeru Stone that seemed to have been built from the practical rock arrangement perspective for the purpose of feasts, etc.

• The Korean Journal of Nuclear Medicine Technology
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• v.19 no.2
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• pp.74-80
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• 2015

Purpose Breast lymphoscintigraphy is an important technique to present for body surface precisely, which shows a lymph node metastasis of malignant tumors at an early stage and is performed before and after surgery in patients with breast cancer. In this study, we evaluated several methods of body outline imaging to present exact location of lesions, as well as compared respective exposure doses. Materials and Methods RANDO phantom and SYMBIA T-16 were used for obtaining imaging. A lesion and an injection site were created by inserting a point source of 0.11 MBq on the axillary sentinel lymph node and 37 MBq on the right breast, respectively. The first method for acquiring the image was used by drawing the body surface of phantom for 30 sec using $Na^{99m}TcO_4$ as a point source. The second, the image was acquired with $^{57}Co$ flood source for 30 seconds on the rear side and the left side of the phantom, the image as the third method was obtained using a syringe filled with 37 MBq of $Na^{99m}TcO_4$ in 10 ml of saline, and as the fourth, we used a photon energy and scatter energy of $^{99m}Tc$ emitting from phantom without any addition radiation exposure. Finally, the image was fused the scout image and the basal image of SPECT/CT using MATLAB$^{(R)}$ program. Anterior and lateral images were acquired for 3 min, and radiation exposure was measured by the personal exposure dosimeter. We conducted preference of 10 images from nuclear medicine doctors by the survey. Results TBR values of anterior and right image in the first to fifth method were 334.9 and 117.2 ($1^{st}$), 266.1 and 124.4 ($2^{nd}$), 117.4 and 99.6 ($3^{rd}$), 3.2 and 7.6 ($4^{th}$), and 565.6 and 141.8 ($5^{th}$). And also exposure doses of these method were 2, 2, 2, 0, and $30{\mu}Sv$, respectively. Among five methods, the fifth method showed the highest TBR value as well as exposure dose, where as the fourth method showed the lowest TBR value and exposure dose. As a result, the last method ($5^{th}$) is the best method and the fourth method is the worst method in this study. Conclusion Scout method of SPECT/CT can be useful that provides the best values of TBR and the best score of survey result. Even though personal exposure dose when patients take scout of SPECT/CT was higher than another scan, it was slight level comparison to 1 mSv as the dose limit to non-radiation workers. If the scout is possible to less than 80 kV, exposure dose can be reduced, and also useful lesion localization provided.