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Salty-taste Activation of Human Brain Disclosed by Gustatory fMRI Study (뇌기능 자기공명영상 장치를 이용한 짠맛 자극에 따른 인간 뇌의 반응에 대한 기초 연구)

  • Kim S.H.;Choi K.S.;Lee H.Y.;Shin W.J.;Eun C.K.;Mun C.W.
    • Investigative Magnetic Resonance Imaging
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    • v.9 no.1
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    • pp.30-35
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    • 2005
  • Purpose : The purpose of this study is to observe the blood oxygen level dependent (BOLD) contrast changes due to the reaction of human brain at a gustatory sense in response to a salty-taste stimulation. Materials and Methods : Twelve healthy, non-smoking, right-handed male subjects (mean age: 25.6, range: 23-28 years) participated in this salty-taste stimulus functional magnetic resonance (fMRI) study. MRI scans were performed with 1.57 GE Signa, using a multi-slice GE-EPI sequence according to a blood-oxy-gen-level dependent (BOLD) experiment paradigm. Scan parameters included matrix size $128\times128$, FOV 250 mm, TR 5000 msec, TE 60 msec, TH/GAP 5/2 mm. Sequential data acquisitions were carried out for 42 measurements with a repetition time of 5 sec for each taste-stimulus experiments. Analysis of fMRI data was carried out using SPM99 implemented in Matlab. NaCl solution $(3\%)$ was used as a salty stimulus. The task paradigm consisted of alternating rest-stimulus cycles (30-second rest, 15-second stimulus) for 210 seconds. During the stimulus period, NaCl-solution was presented to the subject's mouth through plastic tubes as a bolus of delivered every 5 sec using -processor controlled auto-syringe pump. Results : Insula, frontal opercular taste cortex, amygdala and orbitofrontal cortex (OFC) were activated by a salty-taste stimulation $(NaCl,\;3\%)$ in the fMRI experiments. And dosolateral prefrontal cortex (DLPFC) was also significantly responded to salty-taste stimuli. Activation areas of the right side hemisphere were more superior to the left side hemisphere. Conclusion : The results of this study well correspond to the fact that both insula, amygdala, OFC, DLPFC areas are established as taste cortical areas by neuronal recordings in primates. Authors found that laboratory-developed auto-syringe pump is suitable for gustatory fMRI study. Further research in this field will accelerate to inquire into the mechanism of higher order gustatory process.

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Ferucarbotran-Enhanced Hepatic MRI at 3T Unit: Quantitative and Qualitative Comparison of Fast Breath-hold Imaging Sequences (간의 3T 자기공명영상에서 초상자성산화철 조영증강 급속호흡정지영상기법들간의 양적 및 질적 비교평가)

  • Cho, Kyung-Eun;Yu, Jeong-Sik;Chung, Jae-Joon;Kim, Joo-Hee;Kim, Ki-Whang
    • Investigative Magnetic Resonance Imaging
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    • v.14 no.1
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    • pp.31-40
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    • 2010
  • Purpose : To compare the relative values of various fast breath-hold imaging sequences for superparamagnetic iron-oxide (SPIO)-enhanced hepatic MRI for the assessment of solid focal lesions with a 3T MRI unit. Materials and Methods : 102 consecutive patients with one or more solid malignant hepatic lesions were evaluated by spoiled gradient echo (GRE) sequences with three different echo times (2.4 msec [GRE_2.4], 5.8 msec [GRE_5.8], and 10 msec [GRE_10]) for $T2^*$-weighted imaging in addition to T2-weighted turbo spin echo (TSE) sequence following intravenous SPIO injection. Image qualities of the hepatic contour, vascular landmarks and artifacts were rated by two independent readers using a four-point scale. For quantitative analysis, contrast-to-noise ratio (CNR) was measured in 170 solid focal lesions larger than 1 cm (107 hepatocellular carcinomas, nine cholangiocarcinomas and 54 metastases). Results : GRE_5.8 showed the highest mean points for hepatic contour, vascular anatomy and imaging artifact presence among all of the subjected sequences (p<0.001) and was comparable (p=0.414) with GRE_10 with regard to lesion conspicuity. The mean CNRs were significantly higher (p<0.001) in the following order: GRE_10 ($24.4{\pm}14.5$), GRE_5.8 ($14.8{\pm}9.4$), TSE ($9.7{\pm}6.3$), and GRE_2.4 ($7.9{\pm}6.4$). The mean CNRs of CCCs and metastases were higher than those of HCCs for all imaging sequences (p<0.05). Conclusion : Regarding overall performances, GRE using a moderate echo time of 5.8 msec can provide the most reliable data among the various fast breath-hold SPIO-enhanced hepatic MRI sequences at 3T unit despite the lower CNR of GRE_5.8 compared to that of GRE_10.

A Study on the Installation of Groyne using Critical Movement Velocity and Limiting Tractive Force (이동한계유속과 한계소류력을 활용한 수제 설치에 관한 연구)

  • Kim, Yeong Sik;Park, Shang Ho;An, Ik Tae;Choo, Yeon Moon
    • Journal of Wetlands Research
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    • v.22 no.3
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    • pp.194-199
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    • 2020
  • Unlike in the past, the world is facing water shortages due to climate change and difficulties in simultaneously managing the risks of flooding. The Four Major Rivers project was carried out with the aim of realizing a powerful nation of water by managing water resources and fostering the water industry, and the construction period was relatively short compared to the unprecedented scale. Therefore, the prediction and analysis of how the river environment changes after the Four Major Rivers Project is insufficient. Currently, part of the construction section of the Four Major Rivers Project is caused by repeated erosion and sedimentation due to the effects of sandification caused by large dredging and flood-time reservoirs, and the head erosion of the tributaries occurs. In order to solve these problems, the riverbed maintenance work was installed, but it resulted in erosion of both sides of the river and the development of new approaches and techniques to keep the river bed stable, such as erosion and excessive sedimentation, is required. The water agent plays a role of securing a certain depth of water for the main stream by concentrating the flow so much in the center and preventing levee erosion by controlling the flow direction and flow velocity. In addition, Groyne products provide various ecological environments by forming a natural form of riverbeds by inducing local erosion and deposition in addition to the protection functions of the river bank and embankment. Therefore, after reviewing the method of determining the shape of the Groyne structure currently in use by utilizing the mobile limit flow rate and marginal reflux force, a new Critical Movement Velocity(${\bar{U}}_d$) and a new resistance coefficient formula considering the mathematical factors applicable to the actual domestic stream were developed and the measures applicable to Groyne installation were proposed.

A Study on the Meaning and Types of Banpo [斑布] during the Joseon Dynasty (조선시대 반포(斑布)의 의미와 형식 연구)

  • Ree, Jiwon
    • Korean Journal of Heritage: History & Science
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    • v.53 no.3
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    • pp.164-183
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    • 2020
  • In the textile culture of the Joseon Dynasty, the historic record of Banpo is fragmentary and contains many missing details. The main reason is a lack of associated literature, and it is also significant that the actual substance used is not clear at present. Banpo is a kind of cotton, but this has not been confirmed in the traditional textiles that are currently handed down. The word Ban [斑] in Banpo means "stain", and the letter Po [布] means "fabric". At the border of white discourse, Banpo did not receive attention as a research topic. This study is an attempt to restore some of the textile culture of the Joseon Dynasty through Banpo. Banpo is not just limited to the Joseon Dynasty; it is an important material for examining the development of textile culture and exchange in East Asia. This study was broadly divided into three parts. First, the record and meaning of Banpo during the Joseon Dynasty were examined. Records of Banpo can be seen from the early Joseon period during King Sejo and Seongjong, and the production and actual use of Banpo have been confirmed. Banpo was maintained until the beginning of the 20th century, but is no longer observed. Banpo is a woven fabric made of cotton yarn dyed in many colors and has appeared in Southeast Asia since ancient times. In East Asia, there are other fabrics similar to Banpo, such as Ho [縞], Sum [纖], and Chim [綅]. In particular, the correlation between Banpo and Ho is an important link in understanding Banpo in the Joseon Dynasty. Second, the meaning of Banpo was examined from various angles through comprehensive analysis of Chinese and Japanese literature records and cases. The appearance and development of Banpo moved in sync with the period when cotton was introduced into East Asia. In East Asia, cotton was introduced and produced in earnest from the end of the Song Dynasty to the beginning of the Yuan Dynasty, and the meaning of Banpo was diversified. In China, the name of Banpo was changed to Hwapo [花布], Gizapo [碁子布], Gizahwapo [棋子花布], etc. Japan was late to introduce cotton and developed it in acceptance of the changed meaning. In Japan, use of the name Banpo is not on record, but a Ryujo [柳條] fabric of the same type as banpo has been identified. This Ryujo is the same concept as Ho and Hwapo, and later merged into Ho. Names such as Ho, Hwapo, Banpo, etc. were used differently in each country, but the form was shared across East Asia. Third, based on the meaning of Banpo shared in East Asia, the format of Banpo in the Joseon Dynasty was classified. The format of Banpo in the Joseon Dynasty can be divided into grid and striped versions. The name Banpo disappeared over time, but the form remained and was passed down until recently. I hope that this study will help restore Banpo in the future.

Synthesis of Na-A Type Zeolite and Its Ability to Adsorb Heavy Metals (Na-A형 제올라이트의 합성 및 중금속에 대한 흡착능)

  • Chae, Soo-Chun;Jang, Young-Nam;Bae, In-Kook;Lee, Sung-Ki;Ryou, Kyung-Won
    • Journal of the Mineralogical Society of Korea
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    • v.21 no.1
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    • pp.37-44
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    • 2008
  • This study was performed to synthesize Na-A type zeolite with melting slag from the Mapo incineration site and recycle the zeolite as an environmental remediation agent. The melting slag used had a favorable composition containing 26.6% $SiO_2$, 10.9% $Al_2O_3$ and 2.7% $Na_2O$ for zeolite synthesis although there were high contents of iron oxides, including 19.6% $Fe_2O_3$ and 18.9% FeO, which had been used as a flux for the melting. It was confirmed that the Na-A type zeolite could be successfully synthesized at $80^{\circ}C$ and $SiO_2/Al_2O_3\;=\;0.80{\sim}1.96$. The cation exchange capacities (CEC) of the zeolites was determined to be about 220 cmol/kg leveled off at the synthetic time more than 10hrs. The adsorption capacities of zeolite to heavy metals (Cd, Cu, Mn and Pb) were high except for As arid Cr. It was also confirmed through the Eh and pH analysis that As and Cr existed in the forms of $HAsO_4^{2-}$ and $CrO_4^{2-}$. The low absorption rates of zeolite for As and Cr are attributed to the fact that the pore size ($4\;{\AA}$) of Na-A type is smaller than those of $HAsO_4^{2-}$ and $CrO_4^{2-}$ ions ($4\;{\AA}$ ionic radii and $8\;{\AA}$ diameter).

Strategy for Bio-Diversity and Genetic Conservation of Forest Resources in Korea (생물종(生物種) 다양성(多樣性) 및 삼림유전자원(森林遺傳資源) 보존(保存) 전략(戰略))

  • Park, Young Goo
    • Journal of Korean Society of Forest Science
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    • v.83 no.2
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    • pp.191-204
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    • 1994
  • Due to its topographic complexities and various climatical condition, Korea exhibits diverse forest types. Dominant tree species in this zone are Quercus spp., Betula spp., Zelkova spp., Fraxinus spp., Pinus densiflora, Pinus koraiensis, and Pinus thunbergii ete. Genetic conservation in forest species in Korea there are three ways ; one is in situ, other is ex situ and third is in-facility conservation. In situ conservation include that are the present status of conservation of rare and endangered flora and ecosystem, the reserved forest, the national and provincial park, and the gene pool of natural forests. Ex situ conservation means to be established the new forest from in situ forest stands, progeny and provenance test populations, seed orchard and clone banks, and gene conservation in-facility. As a tool for low temperature storage, several aspects on in vitro system were studied ; (1) establishment of in vitro cultures from juvenile and/or rejuvenated tissues, (2) induction of multiple shoots from the individual micropropagules, (3) elongation of the proliferated shoots. Studies on cold storage for short-and long-term maintenance of in vitro cultures under $4^{\circ}C$ in the refrigerator were conducted. For the cryopreservation at $-196^{\circ}C$, various factors affecting survivability of the plant materials are being examined. The necessity of gene conservation of forest trees is enlarged not only to increase the adaptability for various environments but also to gain the breeding materials in the future. For effective gene conservation of forest trees, I would like to suggest followings ; 1. Forest stands reserved for other than the gene conservation purposes such as national parks should be investigated by botanical and gene-ecological studies for selecting bio-diversity and gene conservation stands. 2. Reserved forest for gene pool should be extented both economically important tree spp. and non-economical species. 3. Reserved forest for progeny test and clone bank should be systematically investigated for the use of Ex situ forest gene conservation. 4. We have to find out a new methodology of genetic analysis determining the proper and effective size of subpopulation for in situ gene conservation. 5. We should develop a new tree breeding systems for successful gene conservation and utilization of the genetic resources. 6. New method of in-facility gene conservation using advanced genetic engineering should be developed to save time and economic resources. 7. For the conservation of species with short-life span of seed or shortage of knowledge of seed physiology, tissue culture techniques will be played a great role for gene conservation of those species. 8. It is are very useful conservation not only of genes but of genotypes which were selected already by breeding program. 9. Institutional and administrative arrangements including legistlation must be necessarily taken for gene conservation of forest trees. 10. It is national problems for conservation of forest resources which have been rapidly destroyed because of degenerating environmental condition and of inexperienced management system of bio-diversity and gene conservation. 11. In order to international cooperation for exchanging data of bio-diversity and gene conservation, we should connect to international net works as soon as possible.

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Brewing Characteristics and Condition Setting of Beer Using Rice Flour (쌀가루 혼합맥주의 양조특성 및 조건 설정연구)

  • Lee, Sang-Hyeon;Cheong, Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.9
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    • pp.206-214
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    • 2018
  • This study was conducted from August 2017 to May 2018. Beer was prepared by different ratio of rice and malt and different types of beer, and quality analysis were conducted. The ratio of rice and malt was divided into 0:100 (S0), 20:80 (S1), 40:60 (S2), 60:40 (S3) and 80:20 respectively. We compared the characteristics of the mashing methods(infusion and decoction method) and investigated the characteristics of different types of beer (lager, ale, wheat beer) using yeast (bottom and top yeast). Even with different ratios of rice and malt, normal infusion time was observed and the iodine test was confirmed to be normal. Also, the mashing proceeded normally and the sugar content of the primary wort was between $21.0{\sim}21^{\circ}brix$. In mashing method, the mash concentration, color and flavor of wort were the highest in the three mash method(decoction method). During the fermentation period of beer, the sugar content, pH and yeast number did not differ significantly depending on the ratio of rice and malt, and the type of yeast. Higher alcohol and esters also had no correlation with the ratio of rice to malt, and wheat beer was somewhat higher. The higher the ratio of rice, the more the color intensity(EBC) decreased, the bitter unit(BU) and the preference decreased. When the rice ratio was higher than the malt rate, the degree of preference decreased significantly. Based on the results of this study, it is expected that the rice ratio will be less than the malt ratio and the flavor of the wort will be improved by using the deccoction method. If the malt is supplemented with the use of the special malt and the various hops according to the beer type, it may be helpful to manufacture rice beer.

Neural Bases of Empathy in Competitive vs. non-Competitive situation (경쟁과 비경쟁 상황에서 공감의 신경학적 기제)

  • Hwang, Su-Young;Yoon, Mi-Sun
    • Korean Journal of Cognitive Science
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    • v.27 no.3
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    • pp.441-467
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    • 2016
  • This fMRI study is aim to investigate effects of competitive environment in cognitive empathic process in human brain. Empathy is known as a crucial factor for human's adaptive behavior in aspects of social cognition and it is almost automatic process, on the other hand competitive situation is psychologically devastated environment to win someone for getting rewards. We hypnotized that reading and understanding of other person's mind are a specific characteristic related to survival evolutionarily, however competition would have an effect on the empathic cognitive process because of mechanisms of competition. To manipulate the competitive atmosphere, one researcher took a role of competitor against participants and they were instructed to get monetary rewards when their performance was better than a competitor. 21 participants(9 males and 12 females) performed to judge the emotional valence of the empathic task consisted of illustrated images with various situation could be experienced in real world as on $1^{st}$ person perspective in both competitive and non-competitive condition, and did same performance with objects stimulus in control condition. In order to examine the competition effects on empathic process,, hemodynamic response were obtained during fMRI session and the imaging data were analyzed to identify brain regions where responses to each condition across the two consecutive runs. Participants' reaction time in competitive condition was faster statistically significant than non-competitive one. Activation for competitive condition increased in the following areas: ACC, mPFC, SMG, thalamus extended caudate and Nacc, parahippocampal gyrus, and for non-competitive condition increased paracingulate gyrus, temporal pole, vmPFC, superior occipital gyrus. As a result of regression analysis using empathic scores as covariance, the rSMG, IFG, fusiform gyrus, thalamus, putamen were correlated with higher empathic levels, and TPJ were correlated with lower empathic scores. We suggest that these observations could mean competitive environment have an effect on neural base of cognitive empathic process.

Evaluation of Visual Performance for Implanted Aspheric Multifocal Intraocular Lens in the Cataract Patients (백내장 환자에서 비구면 다초점 인공수정체 삽입 후 시기능 평가)

  • Kim, Jae-Yoon;Lee, Koon-Ja
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.3
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    • pp.347-356
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    • 2013
  • Purpose: To evaluate the visual acuity and visual performance after implantation of a aspheric multifocal (ReSTOR$^{(R)}$ SN6AD3) intraocular lens (IOL). Methods: Nineteen cataract patients (30 eyes) implanted with an aspheric multifocal IOL (ReSTOR$^{(R)}$ SN6AD3) either unilaterally or bilaterally were participated. Visual acuity (VA) and objective optical performance were evaluated at the time of preoperation, 1 week, 1 month, and 3 month after operation. At 3 month of post-operation, objective visual performance were measured and compared with the 38 eyes of 20 age-matched normal control. Distance VA was measured by using the ETDRS LCD chart and intermediate and near visual acuity were measured using Jaeger chart. Objective visual performance was assessed preoperatively and 1 week, 1 month and 3 month postoperatively using a double-pass system (Optical Quality Analysis System) with a 4-mm pupil diameter, the OSI (objective scatter index), MTF (modulation transfer function) cut off and strehl ratio. At 3 month of post-operation, visual acuity and visual performance compared with age matched normal control. Results: The uncorrected distance VA, OSI, MTF cut off and strehl ratio were significantly improved (p<0.05) until 1 month postoperatively. Visual performance of MTF cut off and strehl ratio after 3 month of operation were significantly improved compared to the normal control (p=0.063, p=0.103 respectively), however, OSI was higher than normal control. Patients implanted with aspheric multifocal IOL were satisfied with distance and near VA however, were unsatisfied with intermediate VA and reported glare and halos. Conclusions: The visual performance reaches to a stable condition in 1 month of implantation of aspheric multifocal IOL and improved to the level of age-mated normal patients. Also patients were satisfied with their quality of vision, however, intermediate VA, glare and halos were reported as complications.

A Study on the Policy of Reserved Forests in Korea - mainly, on the designation and cancellation of reserved forests - (보안림정책논고(保安林政策論考) - 보안림(保安林)의 지정(指定) 및 해제(解除)를 중심(中心)으로 -)

  • Choe, Kyu-Ryun
    • Journal of Korean Society of Forest Science
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    • v.4 no.1
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    • pp.1-8
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    • 1965
  • In this study, the present institution of reserved forests in Korea has been criticized through the analysis of the present situation of reserved forests in Korea, and mainly, on designation and cancellation of them because of this important institution thought as restriction of forest ownership. Reserved forest land in Korea as of the end of 1962 is 996,915 chungbo in area, or about 14.8% of the total forest land area, 6,750,324 chungbo in Korea, and we can find that the area of reserved forest land has increased remarkably since the Liberation in 1945, in comparison with about 180,000 chungbo-a little over 1% of the total forest land area, 16,000,000 chungbo, through Southern and Northern Korea till the Liberation in 1945. This fact clearly proves that Korean forests are extremely devastated since the Liberation in 1945, and in Korea we can find that reserved forest policy is very important in forest policy, consequently, reserved forest institution must be dealt with care. Moreover, the area of reserved forest land, 996,915 chungbo, which is divided into 43,820 chungbo of national forest land, 59,302 chungbo of public forest land, 893,793 chungbo of private forest land, and private forest land is excellently large, or about 89.7% of the total area of reserved forest land. In this number, we may understand the fact that reserved forests have the most influences on private forests, therefore, we may recognize that it is necessary for reserved forest constitution which is infringement of private right to be carried out carefully. From the first beginning, the institution of reserved forests is serious restriction to the forest ownership. Consequently, when the area of reserved forest land grows, it interferes seriously with the free forest management and the desire for forest own ership is decreased, at the same time, forest enterprise results in obstruction. Especially, Korean forests are destroyed extremely at present, so, intensification of reserved forest institution is unavoidable for completion of the national aim which forests have, but the author thinks that reserved forest institution must be as avoidable as possible, and we have to obtain good results by supervision of forest management which is regulated in the Forest Law. Consequently, designation of reserved forests must be minimized, and although forests were already designated as reserved forests they must be cancellated as fast as fast as possible and put them free in the owner's hands when they are in cancellation conditions. According to the provision of Article 18 of the Forest Law concrete cases designated as a reserved forest are enumerated for the purpose of maintaining the forest ownership and avoiding to give the forest authorities a free hand in order to protect forest owners from one-sided damage. Therefore, the forest authorities must not abuse the institution of reserved forests, and it is not good tendency to give only the authorities a free hand in eesignation and cancellation of reserved forests, and especially, when the forest owners object to that, establishing some legal organization like the reserved forest council in each province in order to hear about impartial opinions, and it is more suitable than administrative disposal by the same organization. The compensation of damages for reserved forests by the provision of Article 25 of the Forest Law is a different problem by forest policy, but the results of compensation of damages regulated in the Forest Law are wholly lacking up to now, the author thinks that this is caused to poor forest cover, the forest owner's unconcern and insincerity of administrative authorities. Therefore, the government must enlarge the range of compensation and minimize the forest owner's economic sacrifice, also, the government must mollify the conditions of the legal restrictions to reserved forests, and harmonize with functions of national conservation and economy. This means that it is necessary to modify the restrictive conditions for the effective utilization of forest resources within the range in which can be attained the purpose of designation, from permanent prohibition of cutting. Except the reserved forests of fish habitat, public sanitation, maintaining scenery and navigational mark ect., most of reserved forests are prohibited from cutting, and the present situation of forests in Korea are extremely devastated and those forests are not so expected in cancellation possibility in near future. Therefore, when the forest owners apply for national purchase of those reserved forests, the government had better nationalize them, protect and manage to reduce the forest owner's economic sacrifice.

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