• Title/Summary/Keyword: Cutting area

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A Case Study for Applying Linear Programming to Analyze The Effects of The Desired Future Conditions for Forest Functions on Forest Management (산림기능별 목표임상 조건이 산림경영에 미치는 영향분석을 위한 선형계획기법 적용 연구)

  • Jang, Kwangmin;Won, Hyun-Kyu;Seol, A Ra;Chung, Joosang
    • Journal of Korean Society of Forest Science
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    • v.98 no.3
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    • pp.247-254
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    • 2009
  • In this study, linear programming was applied to a case study in Gwangreung Experimental Forest of Korea Forest Research Institute investigating the effect of the desired future conditions on forest management. Considering the social, economic and ecological demands of people from the forest, the forest functions were classified into four including natural conservation, timber production, water yield and scenic conservation. The forest land areas were divided into four-types of forest functional zones and forest management prescriptions including the desired future conditions by the forest function type were established. The Model II linear programming was used in optimizing the forest management planning. The model includes management policies, as the constraints, for non-declining yield, allowable cutting area, allowable % age class distribution and allowable % species allocation as well as the land and other accounting regimes. Maximization of timber production was used the objective function. Based on the Model II formulations, the effects of the desired future conditions by the forest function type on forest management planning were investigated in terms of timber production, net present value and stand structures over time.

Topography and Soil Characteristics Related to Land Creep in 37 Areas in South Korea (우리나라 37개 땅밀림지의 지질 및 토양 특성)

  • Park, Jae-Hyeon;Seo, Jung Il;Ma, Ho-Seop;Kim, Dongyeob;Kang, Minjeng;Kim, Kidae
    • Journal of Korean Society of Forest Science
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    • v.108 no.4
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    • pp.540-551
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    • 2019
  • This study was conducted to provide basic data for classifying patterns of land creep in 37 areas in South Korea using geological and soil property analyses. Geological time, as it relates to land creep areas in South Korea, had been most impactful for the Gyeongsang Supergroup and its sedimentary bedrock during the Cretaceous period. In this area, perfect ridge cliffs in land creeping areas included 20 plots (approximately 54.0%), while tension cracking areas with ambiguous ridge cliff characteristics included 17 plots (approximately 46.0%). Hesitant slide slope types included 20 plots (approximately 54.0%) within theslide slope of an incident pattern (slide slope figure) in land creeping areas. Colluvial debris types among land creep patterns were the most frequent and included 25 plots (approximately 68.0%). The direct causes of land creep were cutting of foothills, quarrying, land-clearing in mountains, mining exploration, and the creation of burial grounds, all of which added to geological impacts. Among land creeping areas, 27 plots (approximately 73.0%) were the result of man-made activities, and 10 plots (approximately 27.0%) were derived via natural causes such as earthquakes, heavy rainfall, and caving.

The Effects of the Breeding site of the Egrets and Herons by Road Construction, Palhyun-ri, Daegu, Korea (대구광역시 팔현리 지역 도로공사가 백로류 번식지에 미치는 영향)

  • Cha, Jae-Seok;Kim, Jae-Woong;Park, Hee-Cheon
    • Korean Journal of Environment and Ecology
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    • v.22 no.2
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    • pp.152-158
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    • 2008
  • This survey was conducted to analyze the effect of road construction near the group breeding places of the egrets and herons located at Palhyun-ri, Daegu, on their breeding during four years from 2003 to 2006. With the number of the individuals of the whole egrets and herons have been decreased due to the three-year road construction work(2003-2005). When the road construction was temporally stopped in 2006, the number of individuals of egrets and herons except Cattle egret Bubulcus ibis increased and partocilarly, the Gray heron Ardea cinerea was found to have been influenced the most by this construction in comparison with other egrets and herons. The number od individuals of large egrets, little egrets and herons was found to decrease during the construction period. After cutting off the nest trees and removing some parts of the breeding site, the herons and egrets tended to move their nesting place from roadsides to the inside of the breeding area. Trees for the nests decreased due to the increase in fellen trees caused by bird nests per tree increased gradually. As for the formation ratio of trees for the nests, the ratio of pine trees lowered yearly while that of acacia and oak trees was increasing during the survey.

A Survey of the Effect of Nursing Students on Community Health Knowledge (간호학생 실습이 지역주민의 보건지식 및 태도에 미치는 영향 -연세대학교 간호대학 보건간호학 실습을 중심으로-)

  • 조원정;김의숙;이정숙
    • Journal of Korean Academy of Nursing
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    • v.3 no.2
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    • pp.111-119
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    • 1973
  • The purpose of this study was to determine whether or not the delivery of health services effects the health knowledge of the recipients of that service. 10 was hypothesized that the practical application of theory, though health services rendered by public health nursing students during their field experiences. would have a positive relationship with the quantity and quality of health knowledge of the female population of a given community. In April 1970, ninety five women(between an age 15-49) from Koyang-Gun were interviewed regarding their knowledge and attitudes in four areas of health: maternal health, child health. family planning and tuberculosis prevention. After 11 years(Nov. l971), during which time the women received home visits by student nurses, the women were again interviewed using the original questionnaire. Additionally, they were asked where they had received information about each question. During the 1$\frac{1}{2}$ year period the visits were made by a total of 112 students. They visited the community twice a week. The result were as follows: Maternal health There was marked improvement in the knowledge of specific aspects of maternal health such as the proper instruments needed for cutting the cord and nutritional precaution of pregnancy (p<0.05). In each case 42.0 percent of more of this knowledge was attributed to information gained from the nursing students. However even after the nursing students'visits, the knowledge of other general areas of maternal remained poor. Child health There were increases in the knowledge of the respondents for the time to supplement breast feeding and for time to wean infants (p<0.05). In each case 35.0 percent or more of this information was attributed to the student. The increase in knowledge regarding types of immunization was more often attributed to the clinic nurse than to the nursing students. Knowledge of the necessity of booster immunization was poor both before and after the visits by the nursing students. Family planing There were significant increases in correct information regarding the time of I.U.D. insertion (P<0.05) and method of taking the oral pill (P<0.05). More than 42.0 percent of the increase was attributed to the nursing students'visits. However there was a slight decrease in correct information about concept of family planning. Tuberculosis There was a general lack of improvement in all areas concerned with tuberculosis. Two thirds of the respondents felt tuberculosis was hereditary and did not know what B.C.G. was. From this study, it could be concluded that in specific area the health knowledge of the female population studied was positively effected by the visits of the nursing students. The study also, suggests, however, that there was a marked unevenness in the overall increase in health knowledge. This raises serious questions which require further research. Suggested areas for further research are (1) Adequacy of the course content preparing nurses for the field experience. (2) A public health nursing manual for student reference. (3) Where and when specific aspects of health can be taught most effectively.

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Resear cher & Coordinator, Canal Reseach & Development, japan (농업수리시설과 소수로굴착용 Trencher V형의 개발에 대하여)

  • 영목청
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.21 no.2
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    • pp.28-36
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    • 1979
  • One of most important problems in the Monsoon Asia today is the production of rice paddy to meet the needs of the ever increasing population. Diversemeans are being employed to meet this demand, both by increasing productivity of existing farm land and by bringing further areas into cultivation. The primary step in either field is to ensure that there is sufficient moisture in the soil to suit the paddy, and at the same this means that excess moisture has to be drained off the land, while in others irrigat ion has to be employed to bring sufficient water to an area. In view of the fact that the project comprises a huge amount of earthwork, it can be carried out by extensive use of construction machinery in order to shorten the period. As farm ditch has a comparatively small section with shallow cutting depth, inaddition, there is lack of access road in the field, the excavation equipment with bulldozer or tracter-shovel (backhoe) type are not applicable because there are mostly adapted for the excavation of deep and wide section. Mini-backhoe with its bucket width not larger than 0. 3m, and width of blade not larger than 1. 00m seems to be more adaptable. About 80% of excavation of ditch section will be done by the machinery while the other 20% of excavation together with the finishing of the section are supposed to be done by man-power. The embankment of ditch section can be compacted by the crawler of backhoe when it is moving along the ditch for excavation. However, Lowland paddy field in the Monsoon Asia are made particulary in rain season, therefore, heavy machinery is not easy excavation for ditch. It is very important to know exact ground support power of the working site and select machines with corresponding ground pressure. Ground support power is variable subject to quality and water content of soil and therefore selection of machines should be made duly considering ground condition of the site at the time of construction works. Farm ditches dug and compacted by mannual labar are of poor quality and subject to destruction after one or two years of operation. On the other hand, excavation and compaction by bulldozer is not practical for ditches. Backboe is suitable for slope land, but this is required cycle time of bucket excavation and dumped out. If a small-scale farm ditch trencher adaptable to lowland paddy field is invented, such a machine could greatly accelerate the massive construction work envisaged in many countries and thus significantly speed up the most difficult part of irrigation development and management in Monsoon Asia.

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The Future of Republic of Korea Navy : Toward a Korean Way of Naval Strategy (미래 대한민국 해군력 역할과 발전)

  • Choi, Joung-Hyun
    • Strategy21
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    • s.37
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    • pp.65-103
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    • 2015
  • This study is an attempt to look into the future role of the ROKN and to provide a strategic way forward with a special focus on naval strategic concept and force planning. To accomplish this goal, this research takes four sequential steps for analysis: 1) assessing the role and utility of naval power of ROKN since its foundation back in 1945; 2) forecasting features of various maritime threats to influence the security of Korea in the future directly or indirectly; 3) identifying the roles to be undertaken by future ROKN; and 4) recommending Korean way of naval force planning and the operational concept of naval power. This study seeks to show that ROKN needs comprehensive role to better serve the nation with respect to national security, national prosperity and development, and future battle-space management. To safeguard the national security of Korea, it suggests three roles: 1) national guard for the peaceful unification; 2) protector of the maritime sovereignty; and 3) suppressor to maritime threats. Three more roles are highlighted for national prosperity: 1) escort of the national economy; 2) guardian for national maritime activities; and 3) contributor to the world peace. These roles need to be closely connected with the role for the battle-space management. This paper addresses the need for a dramatic shift of the central operational domain from land to maritime in the future. This will eventually offer future ROKN a leading role for developing strategic concept and force planning rather than merely a supporting one. This study finally suggests 'balanced' strategy both in concept development and force planning. A balanced force planning is a 'must' rather than an 'option' when considering a division of function between Task Fleets and Area Fleets, constructing cutting-edge conventional forces such as Aegis destroyer, CVs, or submarines, and the mix of high-profile platform and low-profile when composing future fleets. A 'balance' is also needed in operational concept. The fleet should be prepared to fulfill its missions based on two different types of force operation i.e., coercive or cooperative application of the utility of naval force. The findings and recommendations of the study are relevant today, and will be increasingly important in the future to achieve various political goals required by enhancing the utility of naval power.

Development of Dry Process Caisson Method for Maintenance of Submerged Harbor Structure (수중 항만구조물의 유지보수를 위한 건식 케이슨 공법 개발)

  • Lee Joong-Woo;Oh Dong-Hoon;Kwak Seung-Kyu;Kim Sung-Tae
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2006.06b
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    • pp.163-170
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    • 2006
  • Together with the trend of enhancement in domestic industrial development and economic progress due to import and export, the demand for construction of the roads, bridges, especially port facilities, and several coastal protection and ocean structures is increasing rapidly. MOMAF of Korean Government is driving construction of 9 new ports and renovation of the existing fishery ports. Among these structures most of bridge base, wharves, dolphins, quays, and jetties are being newly built of steel or concrete pile. As the base, supporting bulkheads, and piles are underwater after construction, it is difficult to figure out the status of structures and not enough to get maintenance and strengthen the structures. Every year, moreover, these works suck the government budget due to higher incomplete maintenance expense for protection from corrosions of structures and increased underwater construction period. For the purpose of cutting down the expense of government budget, it is necessary to extend the life cycle of the existing structures. Therefore, we developed a new method for maintenance of submerged structures near the waterline by allowing dry work environment with the floating caisson. The method shows easy to move around the working area and handle. It also showed not only a significant reduction maintenance expenses and time for anti-corrosion work but also better protection. This will be a milestone to reduce the maintenance and construction expenses for the shore and water structures.

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Evaluation of Effective Dose and Exposure Level of Radon in Process Handling NORM (인산석고 취급공정에서의 라돈농도 및 유효선량 수준 평가)

  • Chung, Eun Kyo;Jang, Jae Kil;Kim, Jong Kyu;Kim, Joon Beom;Kwon, Jiwoon
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.28 no.3
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    • pp.283-291
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    • 2018
  • Objectives: To monitor the radon concentration level in plants that handle phosphorus rock and produce gypsum board and cement, and evaluate the effective dose considering the effect of radon exposure on the human body. Methods: Airborne radon concentrations were measured using alpha-track radon detectors (${\alpha}$-track, Rn-tech Co., Korea) and continuous monitors (Radon Sentinel 1030, Sun Nuclear Co., USA). Radon concentrations in the air were converted to radon doses using the following equation to evaluate the human effects due to radon. H (mSv/yr) = Radon gas concentration x Equilibrium factor x Occupancy factor x Dose conversion factor. The International Commission on Radiological Protection (ICRP) used $8nSv/(Bq{\cdot}hr/m^3)$ as the dose conversion factor in 2010, but raised it by a factor of four to $33nSv/(Bq{\cdot}hr/m^3)$ in 2017. Results: Radon concentrations and effective doses in fertilizer manufacturing process averaged $14.3(2.7)Bq/m^3$ ($2.0-551.3Bq/m^3$), 0.11-0.54 m㏜/yr depending on the advisory authority and recommendation year, respectively. Radon concentrations in the gypsum-board manufacturing process averaged $14.9Bq/m^3$ at material storage, $11.4Bq/m^3$ at burnability, $8.1Bq/m^3$ at mixing, $10.0Bq/m^3$ at forming, $8.9Bq/m^3$ at drying, $14.7Bq/m^3$ at cutting, and $10.5Bq/m^3$ at shipment. It was low because it did not use phosphate gypsum. Radon concentrations and effective doses in the cement manufacturing process were $23.2Bq/m^3$ in the stowage area, $20.2Bq/m^3$ in the hopper, $16.8Bq/m^3$ in the feeder and $11.9Bq/m^3$ in the cement mill, marking 0.12-0.63 m㏜/yr, respectively. Conclusions: Workers handling phosphorous gypsum directly or indirectly can be assessed as exposed to an annual average radon dose of 0.16 to 2.04 mSv or 0.010 to 0.102 WLM (Working Level Month).

Wording on Acupuncture "鍼" & "針" Used by Historic Doctors (역대의학성씨(歷代醫學姓氏)의 침(針)과 침(鍼)에 대하여)

  • Kim, Hong-Kyoon;An, Sang-Woo
    • The Journal of Korean Medical History
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    • v.25 no.2
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    • pp.155-193
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    • 2012
  • From the part "歷代醫學姓氏(Historic Doctors)" in "醫林撮要(Uirimchualyo)", the following has been noticed and concluded. 1. Because acupuncture was originated from stony needle, the word "石(sok)" contains the meaning of needle, and from this point on, words like 石(sok), 砭石(pyumsok), 箴石(Jamsok), 鑱石(Chamsok) had been derived. 2. The word 砭石(pyumsok) used in "Hwangjenaekyong(Yellow Emperor's Canon of Medicine or Hwangdineijing)" should be interpreted as acupuncture in a verb form, not a noun form. 3. 鑱石(Chamsok) or 鑱鍼(Chamchim) was used for surgical treatment for tumor, by cutting open tumors and pressing the pus out. Therefore, 砭石(pyumsok), 鑱石(Chamsok) are the same kind of needles, and 鑱鍼(Chamchim) is the tool improved from 鑱石(Chamsok) used in the Bronze Age. 4. Kwakpak put a note on 鑱石(Chamsok) in "山海經(Sanhaekyong)" that reads "it is defined as 砥鍼(Jichim) and treats tumor." This let us know the shape of 石(sok), 砭石(pyumsok), 鑱(Chamsok), 鑱鍼(Chamchim), and the stone that can be used as a surgical tool with slim & sharp shape is obsidian. 5. Because obsidian is only found around Mt. Baekdu and limited area in South Korea & Japan in Asia, it is closely related with the life & medical environment of the tribe "Mt. Baekdu". 6. The development of 鑱鍼(Chamchim) was influenced by surgical treatment used in early stage of civilization, and its origin is traced upto Gochosun dynasty. Korea's own traditional medical knowledge is derived from this surgical treatment skill. 7. Because the acupuncture is originated from Gochosun dynasty, 鍼(chim) was derived from 箴(Jam) of 箴石(Jamsok), 䥠(Chim) & 䥠(Chim) both were used for a time being, and finally settled into 鍼(Chim). 8. The word 針(Chim) showed up at Myung dynasty, and started to be used in Korea from early Chosun dynasty. 9. In the early Chosun dynasty, 鍼(Chim) was used for medical term, and 針(Chim) for non-medical term. In the mid Chosun dynasty, 針(Chim) was used as a term for tool, and 鍼(Chim) as a term for acupunctural medical treatment. 10. Under the order of King Sunjo, Dr. Yesoo Yang published "醫林撮要(Uirimchualyo)", added "醫林撮要續集(Sequel to Uirimchualyo)", and added "歷代醫學姓氏(Historic Doctors)" again which eventually made totally 13 books of "醫林撮要(Uirimchualyo)". In addition, many parts of "醫林撮要續集(Sequel to Uirimchualyo)" were quoted in "東醫寶鑑(Donguibogam)", and influenced much in publishing "Donguibogam". 11. In "歷代醫學姓氏(Historic Doctors)" of "醫林撮要(Uirimchualyo)", the same way in "Donguibogam", referred to 針(Chim) as a term for a needle, and 鍼(Chim) as a term for Acupuncture. 12. From the usage of 針(Chim) & 鍼(Chim), shown in "鄕藥集成方(Hyangyakjipsungbang)", "醫林撮要(Uirimchualyo)" and "東醫寶鑑(Donguibogam)", we can notice the spirit of doctors who tried to take over the legitimacy of Korean tradition, and their elaboration & historical view that expresses confidence on our own medical technology, through the wording 鍼(Chim).

Recent Research Trends of Cryopreservation Technology Based on Microalgae Chlorophyta (미세조류 동결보존 기술 개발의 최근 연구 동향)

  • Yim, Jun-Ho;Seo, Yong Bae;Kim, Seon Min;Jeon, Young Jae
    • Journal of Life Science
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    • v.31 no.10
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    • pp.960-968
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    • 2021
  • Since microalgae research started on late 18 century, they have been recognized as one of the most important bioresources used in bioindustry. Owing to the large efforts paid to industrial application of this microorganisms, their importance on food/feed and bioactive compounds has been further extending into the environmental research areas including alternative energy resources, mitigation of the carbon emission, and waste-water treatment. However, despite the importance on their industrial application, the fundamental research field related to the long-term preservation of microalgae culture has not received much attention. However, a less labor intensive and cost-efficient preservation technology enabling biologically active and stable microalgae-culture provides a key success factor in the biotechnological application. Therefore, this study investigated various cutting-edge microalgae cryopreservation technologies currently developed so far, mainly targeting Chlorophyta, which occupies the largest taxon in the classification system of microalgae. In addition, for the development of successful cryopreservation technique, the key factors such as temperature control effect and preservative effect during cryopreservation of microalgae culture were investigated. In addition, the problems with current preservation technology that is being used in Korean domestic biological resource banks and the international microalgal resource banks are described. According to our investigation, currently no standard method for long-term preservation of microalgae is available due to their various morphological and physiological characteristics. To overcome such issues, much more efforts on fundamental research area on the identification of specific biomarker used for microalgae taxonomical classification and further systemic approaches based on strain-specific cryopreservation methods needed.