• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.6
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• pp.521-537
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• 2012

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2011. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of fluid machinery and fluid flow, thermodynamic cycle, and new and renewable energy. Various topics were presented in the field of fluid machinery and fluid flow. Research issues mainly focused on the rankine cycle in the field of thermodynamic cycle. In the new and renewable energy area, researches were presented on geothermal energy, fuel cell, biogas, reformer, solar water heating system, and metane hydration. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer, nanofluids and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer above liquid helium surface in a cryostat, methane hydrate formation, heat and mass transfer in a liquid desiccant dehumidifier, thermoelectric air-cooling system, heat transfer in multiple slot impinging jet, and heat transfer enhancement by protrusion-in-dimples. In the area of pool boiling and condensing heat transfer, researches on pool boiling of water in low-fin and turbo-B surfaces, pool boiling of R245a, convective boiling two-phase flow in trapezoidal microchannels, condensing of FC-72 on pin-finned surfaces, and natural circulation vertical evaporator were actively performed. In the area of nanofluids, thermal characteristics of heat pipes using water-based MWCNT nanofluids and the thermal conductivity and viscosity were measured. In the area of industrial heat exchangers, researches on fin-tube heat exchangers for waste gas heat recovery and Chevron type plate heat exchanger were implemented. (3) Refrigeration systems with alternative refrigerants such as $CO_2$, hydrocarbons, and mixed refrigerants were studied. Heating performance improvement of heat pump systems were tried applying supplementary components such as a refrigerant heater or a solar collector. The effects of frost growth were studied on the operation characteristic of refrigeration systems and the energy performance of various defrost methods were evaluated. The current situation of the domestic cold storage facilities was analyzed and the future demand was predicted. (4) In building mechanical system fields, a variety of studies were conducted to achieve effective consumption of heat and maximize efficiency of heat in buildings. Various researches were performed to maximize performance of mechanical devices and optimize the operation of HVAC systems. (5) In the fields of architectural environment and energy, diverse purposes of studies were conducted such as indoor environment, building energy, and renewable energy. In particular, renewable energy and building energy-related researches have mainly been studied as reflecting the global interests. In addition, various researches have been performed for reducing cooling load in a building using spot exhaust air, natural ventilation and energy efficiency systems.

• Journal of the Korean association of regional geographers
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• v.4 no.2
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• pp.49-64
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• 1998

Bing-gye valley(Kyongbuk Province, South Korea) is well known as a tourist attraction because of its meteorologic characteristics that show subzero temperature during midsummer. Also, there are some interesting geomorphic features in the valley area. Therefore, the valley is worth researching in geomorphology field. The aim of this paper is to achieve two purposes. These are to clarify geomorphic features on talus within Bing-gye valley area, and to infer the origin of Bing-gye valley. The main results are summarized as follows. 1) The formation of Bing-gye valley It would be possible to infer the following two ideas regarding the formation of Bing-gye valley. One is that the valley was formed by differential erosion of stream along fault line, and the other is that the rate of upheaval comparatively exceeded the rate of stream erosion. Especially, the latter may be associated with the fact that the width of the valley is much narrow. Judging that the fact the width of the valley is much narrow, compared with one of its upper or lower valley, it is inferred that Bing-gye valley is transverse valley. 2) The geomorphic features of talus (1) Pattern It seems to be true that the removal of matrix(finer materials) by the running water beneath the surface can result in partly collapse hollows. Taluses are tongue-shaped or cone-shaped in appearance. They are $120{\sim}200m$ in length, $30{\sim}40m$ in maximum width. and $32{\sim}33^{\circ}$ in mean slope gradient. The component blocks are mostly homogeneous in size and shape(angular), which reflect highly jointed free face produced by frost action under periglacial environment. (2) Origin On the basis of previous studies, the type of the talus is classified into rock fall talus. When considered in conjunction with the degrees of both weathering of blocks and hardness of blocks, it can be explained that the talus was formed under periglacial environment in pleistocene time. (3) The inner structure of block accumulation I recognize a three-layered structure in the talus as follows: (a) superficial layer; debris with openwork texture at the surface, 1.3m thick. (b) intermediate layer: small debris(about 5cm in diameter) with fine matrix(including humic soil), 70cm thick. (c) basal layer: over 2m beneath surface, almost pure soil horizon without debris (4) The stage of landform development Most of the blocks are now covered with lichen, and/or a mantle of weathering. It is believed that downslope movement by talus creep well explains the formation of concave slope of the talus. There is no evidence of present motion in the deposit. Judging from above-mentioned facts, the talus of this study area appears to be inactive and fossil landform.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.1
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• pp.1-6
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• 2016

The growth of Italian ryegrass (IRG) after wintering was very low in 2015 when IRG was broadcasted under growing rice in fall of 2014. To determine growth inhibitory factors of IRG, we examined the growth conditions of IRG in Nonsan region and meteorological conditions in Daejeon nearby Nonsan. Minimum temperature and maximum instantaneous wind speed on Feb. $8^{th}$ and $9^{th}$ of 2015 after wintering of IRG were $8.8^{\circ}C$, 10.7 m/s and $12.4^{\circ}C$, 9.6m/s, respectively. Air temperature was suddenly dropped due to strong wind with snow showers, which had unfavorable effect on root growth of IRG exposed at the soil surface. The minimum temperature and maximum instantaneous wind speed on Feb. $12^{th}$, $13^{th}$, and $14^{th}$ of 2015 were $4.1^{\circ}C$, 11.6 m/s, $-5.6^{\circ}C$, 10.3 m/s, and $-4.7^{\circ}C$, 7.5 m/s, respectively. The growth circumstance of IRG was not good because soil was dried due to drought continued from January. The minimum temperature and maximum instantaneous wind speed on Feb. $26^{th}$, $27^{th}$, and $28^{th}$ of 2015 were $1.8^{\circ}C$, 13.7 m/s, $-3.5^{\circ}C$, 10.6 m/s, and $4.1^{\circ}C$, 6.8 m/s, respectively. The number of wilting of IRG was more than 59% until Mar. $3^{rd}$ of 2015. IRG faced irreparable environment (low minimum temperatures and extreme instantaneous wind speeds) for 9 days from Mar. $4^{th}$ to Mar. $12^{th}$ of 2015. The main reason for the decrease of IRG productivity was collection delay of rice straw after rice harvest because there was continuous rain between Oct. and Nov. of 2014. For this reason, weakly grown IRG under rice straw was withered after wintering. IRG was withered by frost heaving, drought, and instantaneous wind speed in the spring. Furthermore, the root of IRG was damaged while growing in excess moisture in the surface of paddy soil during the winter season due to rain.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.1
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• pp.26-32
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• 2014

'Dahan' (Avena sativa L.), a winter oat cultivar for forage use, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute Crop Science (NICS), Rural Development Administration (RDA) in 2011. It was derived from an original cross between $F_1$[Sprinter/73625] and 'Gwiri26'. Subsequent generations followed by the cross were handled in bulk and pedigree selection programs at Suwon. A line, 'SO99027-GB-B-113-4-4-3', was selected for cold tolerance and good agronomic characteristics and as a line name of 'Gwiri75'. The line 'Gwiri75' was subsequently evaluated for cold tolerance and forage yield during 3 years in four region such as Yesan, Iksan, Kimjae, and Jeju, from 2009 to 2011 and finally named as 'Dahan'. Though similar in heading date to the check cultivar Samhan, 'Dahan' had tall plant length and lodging resistance. It's average forage dry matter yield harvested at milk-ripe stage was 15.6 ton $ha^{-1}$, compared with 14.1 ton $ha^{-1}$ of check cultivar. Cultivar 'Dahan' was lower to the check cultivar 'Samhan' in protein content (8.4% and 9.9%, respectively), while it was superior to the check cultivar in total digestible nutrients (TDN) (60.8% and 59.3%, respectively), and in TDN yield $ha^{-1}$ (9.5 ton and 8.4 ton, respectively). Fall sowing of 'Dahan' is recommended only in the areas where daily minimum mean temperatures are averaged higher than $-7^{\circ}C$ in January, and excluded in mountain area where frost damage is presumable.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.227-233
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• 2013

'Taehan' (Avena sativa L.), a winter oat for forage use, was developed by the breeding team at the Department of Rice and Winter Cereal Crops, NICS, RDA in 2012. It was derived from a cross between 'Malgwiri' and 'CI8015'. Subsequent generations were handled in bulk and pedigree selection programs at Suwon and Yeoncheon, respectively. After 2 years of preliminary and advanced yield tests, 'SO00020B-YB-15-5-9-4-3', designated as 'Gwiri78', were subsequently evaluated for earliness and forage yield during 3 years in four regions such as Yesan, Iksan-1 (Paddy), Iksan-2 (upland), and Jeju from 2010 to 2012, and finally named 'Taehan'. Over 3 years, the heading date of 'Taehan' was about 6 days earlier than that of the check cultivar 'Samhan' (May 8 and May 14, respectively), and their average forage dry matter yield harvested at the milk-ripe stage was 14.5 tone $ha^{-1}$, compared with 14.1 tone $ha^{-1}$ for the check cultivar. The cultivar 'Taehan' was lower than that of the check cultivar 'Samhan' in terms of protein content (6.3% and 7.7%, respectively) and total digestible nutrients (60.7%, and 62.1%, respectively). The TDN yield was more than that of the check cultivar (9.1 tone $ha^{-1}$ and 8.0 tone $ha^{-1}$, respectively). Fall cropping of 'Taehan' is recommended only in areas where average daily minimum mean temperatures in January are > $-6^{\circ}C$, and it should not be cultivated in mountainous areas, where frost damage is likely to occur.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.3
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• pp.11-24
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• 2020

The purpose of this study was to re-examine the neglected and forgotten Cheongdo Geoyeonjeong, to correct the wrong contents, examine the changes and conditions of the garden, and to establish basic data on the components of the forest in the future. In addition, it was extended to the Gongampungbyeog Cliff, the influence area of the Geoyeonjeongwonlim, and the results of the study were as follows; First, Based on the recitation of "Seonyu pungryu(仙遊風流)" in the "Cheongsuheon-yugo(聽水軒遺稿),", Dongchangcheon Stream and Gongampungbyeog(孔巖楓壁) were influenced by the outer gardens of the Georyeonjeongwonrim. Second, Small pavilion was built and arranged under the rock of Byeongam(Byeongpungbawi) in the management history of Geoyeonjeong Pavilion. The records show that Cheongsuheon used the Geoyeonjeong Pavilion as the original forest and even recognized Oewon, which is a scenic influence, as the Gongampungbyeog Cliff. Third, Many of the poems related to Gongam were recognized as Seunggyeong, which represents the Unmun area, and the eight scenery of Cheongdo and Unmungugok were established here as proof that Gongampungbyeog Cliff was very faithful to the traditional Seunggyeong aspect of Gongampungbyeog Cliff, and the crystalline structure of the location was implied as an external source of Geoyeonjeongwonlim. Fourth, The lower part of Dongchangcheon Stream, which stretches from Geoyeonjeongwonrim to Gongam, is filled with attractions consisting of cancerous areas such as Punghodae, Moseongam, Buangdae, Gokcheondae, Saganjeong, Hakgadae, and Hyeongjeam, which provide a clearer picture of the space and landscape of the Geyeonjeongwonrim Outer Garden. Fifth, The expression "dragging water, spilling it into the courtyard, and sending it back to the downtown of the field" of the Cheongsuheon-yugo suggests that the site of Geoyeonjeong Pavilion was originally a prevention. It is also inferred that Cheng Shu-heon also wanted to respect runners and pursue natural views like runners. Sixth, The record of planting a description of spring water and willow trees in "Geoyeonjeong Manyeong(居然亭晩影)」" and "Sanggukseol(霜菊說)」" suggests that the chrysanthemum was planted and planted, and that the chrysanthemum was used to describe the Osanggojeol(傲霜孤節), which means that he would not yield and keep his incision alone despite severe frost. Seventh, It is believed that the writing was written by Cheongsuheon in 1844 during the period of the creation of the Wonrim. The rock letters on the floor of Geoyeonjeong suggest the names of the receiving and the winning prizes. Most of the passages are based on nuclear power plants, including Muidogyo of the Zhuzi, and most of them incorporate the virtues of the Gunja and the natural views of the Eunja. In addition, the rock writing 'Gyeong(敬)' or 'Uidang(義堂)' is a substitute for special worship objects or introspection, adding to the significance and scenic properties of the Georyeon Garden Forest.

• Korean Journal of Breeding Science
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• v.41 no.1
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• pp.56-60
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• 2009

A new naked oat cultivar Daeyang (Avena sativa L.) was developed by Department of Rice and Winter Cereal Crop, NICS, RDA in 2007. It was derived from a cross between 'FLX446-1-84-Q1'. and 'SO92004-B-3-3-5-7'. The FLX446-1-84-Q1, a naked oat cultivar from USA, is early heading and has good seed quality, while the SO92004-B-3-3-5-7, a covered oat breeding line, has a high yield with large grain. Subsequent generations were handled in a bulk method and pedigree selection program, and the SO97013-B-16-4 was selected based on agronomic performance in 2001. The line showed both high yield and good husking rate of seed in the yield trial tested at Suwon from 2002 to 2003, being designated as Gwiri51. The Gwiri51 was subsequently evaluated for winter hardiness, earliness, and yield in four locations, Gimje, Iksan, Jeongeup, and Jinju, from 2004 to 2007 and was designated as "Daeyang" and released. Its heading date was May 8 and maturing time was June 14 in a paddy field condition. The new cultivar Daeyang had 97 cm of culm length and 25.2 cm of spike length, 644 spikes per $m^2$, 65 grains per spike, 30.3 g of 1,000-grain weight, and 635 g of test weight. Daeyang showed better winter hardiness than that of the check cultivar 'Sunyang', and similar seed quality to the check cultivar in respect to percent content crude protein and $\beta$-glucan. However, it showed higher husking rate than the check cultivar. Grain yield of Daeyang in the regional yield trial for 4 years were averaged 4.18 MT $ha^{-1}$, which was 20% higher than that of the check cultivar Sunyang. Fall sowing cropping is recommended only in a south area where daily minimum mean temperatures are averaged higher than $-4^{\circ}C$ in January, and should be excluded in mountain area where frost damage is presumable.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.6
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• pp.427-446
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• 2008

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2006 has been accomplished. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environments. The conclusions are as follows. (1) The research trends of fluid engineering have been surveyed as groups of general fluid flow, fluid machinery and piping, etc. New research topics include micro heat exchanger and siphon cooling device using nano-fluid. Traditional CFD and flow visualization methods were still popular and widely used in research and development. Studies about diffusers and compressors were performed in fluid machinery. Characteristics of flow and heat transfer and piping optimization were studied in piping systems. (2) The papers on heat transfer have been categorized into heat transfer characteristics, heat exchangers, heat pipes, and two-phase heat transfer. The topics on heat transfer characteristics in general include thermal transport in a cryo-chamber, a LCD panel, a dryer, and heat generating electronics. Heat exchangers investigated include pin-tube type, plate type, ventilation air-to-air type, and heat transfer enhancing tubes. The research on a reversible loop heat pipe, the influence of NCG charging mass on heat transport capacity, and the chilling start-up characteristics in a heat pipe were reported. In two-phase heat transfer area, the studies on frost growth, ice slurry formation and liquid spray cooling were presented. The studies on the boiling of R-290 and the application of carbon nanotubes to enhance boiling were noticeable in this research area. (3) Many studies on refrigeration and air conditioning systems were presented on the practical issues of the performance and reliability enhancement. The air conditioning system with multi indoor units caught attention in several research works. The issues on the refrigerant charge and the control algorithm were treated. The systems with alternative refrigerants were also studied. Carbon dioxide, hydrocarbons and their mixtures were considered and the heat transfer correlations were proposed. (4) Due to high oil prices, energy consumption have been attentioned in mechanical building systems. Research works have been reviewed in this field by grouping into the research on heat and cold sources, air conditioning and cleaning research, ventilation and fire research including tunnel ventilation, and piping system research. The papers involve the promotion of efficient or effective use of energy, which helps to save energy and results in reduced environmental pollution and operating cost. (5) Studies on indoor air quality took a great portion in the field of building environments. Various other subjects such as indoor thermal comfort were also investigated through computer simulation, case study, and field experiment. Studies on energy include not only optimization study and economic analysis of building equipments but also usability of renewable energy in geothermal and solar systems.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.512-516
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• 2008

A new naked oat cultivar 'Choyang' (Avena sativa L.) was developed by the breeding team at the Department of Rice and Winter Cereal Crop, NICS, RDA in 2007. It was derived from a cross between 'Sikyonggwiri' and 'Gwiri23'. The cultivar, Sikyonggwiri is early heading while the breeding line Gwiri23 has a high yielding potential with large-size grain. Bulk method combined with pedigree selection program was employed in subsequent generations, and the promising line SO96025-B-303-44-2-5 was selected for agronomic performance in 2002. The line showed both high yield and good husking rate of seed in the Yield Trial tested at Suwon in 2003 to 2004, and was subsequently designated as 'Gwiri57'. Gwiri57 was evaluated for winter hardiness, earliness, and yield in four locations, Gimje, Iksan, Jeongeup and Jinju from 2005 to 2007 and was released as Choyang. Choyang headed 11 days earlier and matured 5 days earlier than the check cultivar 'Sunyang' in the paddy field condition. The new cultivar Choyang had 97 cm of culm length and 23.4 cm of spike length, 658 spikes per $m^2$, 75 grains per spike, 28.8 g of 1,000-grain weight, and 636 g of test weight. Choyang showed better winter hardiness than that of the check cultivar Sunyang, and similar seed quality to the check cultivar in respect to crude protein (12.9%) and ${\beta}$-glucan content (4.7%). However, it showed higher husking rate than the check cultivar. The grain yield of Choyang in the regional yield trial for 3 consecutive years was averaged $4.67MT\;ha^{-1}$, which was 38% higher than that of the check cultivar Sunyang. Choyang is recommended for the fall sowing cropping only in the southern area where daily minimum mean temperatures are averaged higher than $-4^{\circ}C$ in January, and is not recommended the in mountain area where frost damage is presumable.

• Korean Journal of Heritage: History & Science
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• v.47 no.2
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• pp.86-113
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• 2014

This study has researched the characteristics and elements of Chwibyeong (翠屛), a sort of trellis in the Joseon Dynasty through the old documents, and the original form of Chwibyeong at Juhapru (宙合樓) in Changdeuk Palace. The results were as follow. First, as the result of literatures analysis for Imwon-gyeongje-ji (林園經濟志) and Jeungbo-sallim-gyeongje (增補山林經濟), the plant screen was classified as kinds of support[frame] material, plants and methods of planting. It was found that the supports of Chwibyeong were made of bamboo or the material such as the Jinjangmok (眞長木: a stick of oak) and Giryu (杞柳: Salix purpurea var. japonica). The evergreen coniferous trees including Pinus densiflora, Taxus cuspidata and Thuja orientalis were mainly used for the plant material of Chwibyeong. The general planting method of Chwibyeong was to plant on the ground, but sometimes the container planting was also found on the artificial ground. Second, the term of 'Chwibyeong' in the literatures was used in only the screen made by evergreen trees, and the superordinate category term of it was indicated by 'byeong (屛)'. Therefore Chwibyeong was a compound word formed from 'chwi (翠)' which means the characteristics of evergreen and 'byeong' as tree screen which the support was made by bamboo. And Chwibyeong had semantic context which was combined with the literary symbolization to describe a landscape of green peak and Taoist ideology be inherent from 'twelve peaks of Musan[巫山十二峰]' in Sichuan sheng (四川省). Thirdly, the photograph of Chwibyeong at Juhapru taken by the 1880s, showed that Chwibyeong was made with coniferous trees and was almost 2 meters high. The Chwibyeong at Juhapru was removed during the Japanese colonial era, but a few yew trees(Taxus cuspidata) used for Chwibyeong are still remaining. And some Juniperus chinensis which the composition time is unclear, were cultivated while hung loose its branchs at the sides of Eosumun (魚水門). This Junipers were presumed to be planted by Japanese after Japanese annexation of Korea(1910), and it was judged that both of the roofs of Eosumun's side gates might have been transformed into Japanese style at the same time. Lastly, Chwibyeong at Juhapru was restored in 2008 but it was restored in wrong way from original form without precise research. Especially Chwibyeong was restored with Sasa boreralis which is damaged by frost, so it requires exertion that should revive the originals to plant original material as much as possible. And it needs the development of fabrication technique for Chwibyeong and the application to current landscape architecture.