• Journal of Korean Society of Forest Science
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• v.40 no.1
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• pp.19-24
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• 1978

The study was conducted to find out the relationship between land cost and financial yield earned by the plantations of Pinus koraiensis, Pinus densiflora and Cryptomeria japonica, and to investigate possible land investment for the given rates of return. The result of the study could be summarized as follows: 1. In the case of Pinus koraiensis plantation on site index 12, the finnancial yield was 6.4 percent when the land cost was 0.5 million Won per hectare, but the yield was reduced to 2.1 percent when the cost was 2.5 million Won. It would be therefore necessary for inducing plantation investment to raise financial yield by control of forest land price. 2. The financial yield on land of zero expectation value, in other words, internal rate of return of land investment was estimated at 10 percent. If the opportunity cost of forest land is higher than this, the economic plantation is not visible even though the land is free. 3. With the expected financial yield of 3 percent, the possible land investment of poor sites was estimated at 1.24, 0.28 and 0.80 million Won per hectare for the plantation of Pinus koraiensis, Pinus densiflora and Cryptomeria japonica, respectively. In any case, however, land cost could not be over 3 million Won per hectare. 4. The rate earned from forest land investment was generally less than 10 percent. Therefore, the annual interest rate in forestry could not be higher than this, and hopeful rate is not exceeding 6 percent.

• Journal of Korean Society of Forest Science
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• v.60 no.1
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• pp.30-36
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• 1983

Plywood, the representative interior decorative or structural material, is so inflammable that it may cause big fires. Therefore, it is required inevitably to manufacture the "Fire retardant treated plywood", and it will be a study on the redrying of treated plywood that we ought to solve. This study was carried out to investigate the absorption of 20% $(NH_4)_2HPO_4$ solution into the soaked plywoods by hot/cold soaking for 3/3, 6/3, 9/3 and 12/3 hours and to study drying process with drying curves and drying rates by press-drying at the platen temperature of 130, 145, 160 and $175^{\circ}C$. Solution absorption of plywoods in hot/cold soaking method increased steadily with the prolonged soaking time, and water absorption is higher than DAP absorption, and then chemical retention (DAP) exceeded the minimum retention [$1.125kg/(30cm)^3$] even in the shortest soaking treatment. Drying curves of water-soaked plywoods inclined more steeply than those of DAP soaked plywoods. And the drying proceeded rapidly with the increase in platen temperature and terminated in 2.5-4 minutes at the temperature of 160 and $170^{\circ}C$. Drying rate also increased generally with the increase of platen temperature. So it was at $175^{\circ}C$ in DAP-soaking and at $160^{\circ}C$ in water-soaking when the drying rate became above 10%/min.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.761-766
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• 2015

This study investigated the effect of protease on quality characteristics of sponge cake. Protease was used at levels of 0.0005 U (PC-1), 0.0010 U (PC-2), 0.0015 U (PC-3), and 0.0020 U (PC-4) for sponge cake preparation. Amylogram showed the setback was significantly decreased in comparison with the control (P<0.05). Height and baking loss rate of control sponge cake were $4.24{\pm}0.18cm$ and $12.01{\pm}0.29%$, respectively. PC-3 and PC-4 showed increased heights of $5.22{\pm}0.16$ and $5.24{\pm}0.11cm$ as well as slightly increased baking loss rates of $12.71{\pm}0.31%$ and $12.89{\pm}0.61%$, respectively. Specific volume and color difference measurements of control showed a specific volume of $3.53{\pm}0.06mL/g$, crust color difference of $53.05{\pm}0.28$, and crumb color difference of $29.84{\pm}0.52$. Measurements of specific volume, crust color, and crumb color of PC-3 and PC-4 were $4.18{\pm}0.02mL/g$, $56.19{\pm}0.84$, $29.05{\pm}0.43$, $4.21{\pm}0.02mL/g$, $56.85{\pm}0.43$, and $29.45{\pm}0.47$, respectively. Firmness measurements showed that the control had the highest firmness. PC-3 and PC-4 were effective at improving the shelf-life of sponge cake as indicated by reduced firmness. Sensory evaluation results demonstrated that all samples scored higher than the control. Throughout the results, the addition of protease increased volume and improved quality characteristics of sponge cake.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.752-760
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• 2015

Effects of maltogenic amylase on textural properties of dough and quality characteristics of white pan bread were investigated. White pan bread was prepared with four different levels of maltogenic amylase contents (M-1: 0.048 U/g, M-2: 0.060 U/g, M-3: 0.072 U/g, M-4: 0.084 U/g). The setback by amylograph for the control was $480.0{\pm}12.25$ Brabender Unit (B.U.) while M-4 showed the a setback of $215.0{\pm}5.00B.U.$ The absorption, mixing tolerance index, and stability by farinogram were not significantly different (P>0.05) for across all treatments. The area under the curve (135 min) by extensogram was higher than all samples. The texture profile analysis results showed that there was significant decreasing in hardness for the maltogenic amylase infused bread (P<0.05). M-3 and M-4 showed higher springiness and cohesiveness but lower hardness than control over 1 to 3 days, indicating possibly extended shelf-life. Imaging scan showed that air cell size less than $0.4mm^2$ for the control and M-4 were at rates of 94.90% and 95.70%, respectively. For sensory evaluation, M-3 and M-4 showed higher intensities than the control for taste, flavor, texture, mouthfeel, and moistness quality. These results imply that the quality of white pan bread could be improved by adding maltogenic amylase without the use of chemical additives.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1504-1509
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• 2015

The aim of this study was to investigate a validation method for determination of pectolinarin and pectolinarigenin in fermented Cirsium setidens Nakai. For validation, the specificity, linearity, precision, accuracy, detection limits, and quantification limits of pectolinarin and pectolinarigenin were measured by HPLC. The results show that the detection limits of pectolinarin and pectolinarigenin were $4.25{\mu}g/mL$ and $2.46{\mu}g/mL$, respectively. The recovery rates of pectolinarin and pectolinarigenin were high in the ranges of 99.7~104.0% and 99.7~102.4%, respectively. Inter-day and intra-day precisions of pectolinarin and pectolinarigenin in fermented Cirsium setidens Nakai were 0.9%, 0.5% and 0.5%, 0.2%, respectively. Therefore, application of pectolinarin and pectolinarigenin was validated by an analytical method as a marker compound in Cirsium setidens Nakai.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2000.04a
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• pp.9-10
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• 2000

An important business-field of world-wide steel-industry is the coating of thin metal-sheets with zinc, zinc-aluminum and aluminum based materials. These products mostly go into automotive industry. in particular for the car-body. into building and construction industry as well as household appliances. Due to mass-production, the processing is done in large continuously operating plants where the mostly cold-rolled metal-strip as the substrate is handled in coils up to 40 tons unwind before and rolled up again after passing the processing plant which includes cleaning, annealing, hot-dip galvanizing / aluminizing and chemical treatment. In the liquid Zn, Zn-AI, AI-Zn and AI-Si bathes a combined action of corrosion and wear under high temperature and high stress onto the transfer components (rolls) accounts for major economic losses. Most critical here are the bearing systems of these rolls operating in the liquid system. Rolls in liquid system can not be avoided as they are needed to transfer the steel-strip into and out of the crucible. Since several years, ceramic roller bearings are tested here [1.2], however, in particular due to uncontrollable Slag-impurities within the hot bath [3], slide bearings are still expected to be of a higher potential [4]. The today's state of the art is the application of slide bearings based on Stellite\ulcorneragainst Stellite which is in general a 50-60 wt% Co-matrix with incorporated Cr- and W-carbides and other composites. Indeed Stellite is used as the bearing-material as of it's chemical properties (does not go into solution), the physical properties in particular with poor lubricating properties are not satisfying at all. To increase the Sliding behavior in the bearing system, about 0.15-0.2 wt% of lead has been added into the hot-bath in the past. Due to environmental regulations. this had to be reduced dramatically_ This together with the heavily increasing production rates expressed by increased velocity of the substrate-steel-band up to 200 m/min and increased tractate power up to 10 tons in modern plants. leads to life times of the bearings of a few up to several days only. To improve this situation. the Mechanical Alloying (MA) TeChnique [5.6.7.8] is used to prOduce advanced Stellite-based bearing materials. A lubricating phase is introduced into Stellite-powder-material by MA, the composite-powder-particles are coated by High Energy Milling (HEM) in order to produce bearing-bushes of approximately 12 kg by Sintering, Liquid Phase Sintering (LPS) and Hot Isostatic Pressing (HIP). The chemical and physical behavior of samples as well as the bearing systems in the hot galvanizing / aluminizing plant are discussed. DependenCies like lubricant material and composite, LPS-binder and composite, particle shape and PM-route with respect to achievable density. (temperature--) shock-reSistibility and corrosive-wear behavior will be described. The materials are characterized by particle size analysis (laser diffraction), scanning electron microscopy and X-ray diffraction. corrosive-wear behavior is determined using a special cylinder-in-bush apparatus (CIBA) as well as field-test in real production condition. Part I of this work describes the initial testing phase where different sample materials are produced, characterized, consolidated and tested in the CIBA under a common AI-Zn-system. The results are discussed and the material-system for the large components to be produced for the field test in real production condition is decided. Outlook: Part II of this work will describe the field test in a hot-dip-galvanizing/aluminizing plant of the mechanically alloyed bearing bushes under aluminum-rich liquid metal. Alter testing, the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed. Part III of this project will describe a second initial testing phase where the won results of part 1+11 will be transferred to the AI-Si system. Part IV of this project will describe the field test in a hot-dip-aluminizing plant of the mechanically alloyed bearing bushes under aluminum liquid metal. After testing. the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.2
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• pp.147-154
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• 2019

Objectives : Cognitive dysfunction, including inattention, is often observed in patients with depression. Inattentive symptoms in patients with depression is similar to those among attention deficit/hyperactivity disorder (ADHD) patients. It is important to diagnose the two diseases accurately, because the treatment varies depending on the cause of inattention. This study aimed to investigate the coexistence rate of ADHD and the correlation between ADHD symptoms and depression in patients with depression. Methods : Participants in this study were 158 outpatients presenting with depression, who visited the psychiatric department from March 2015 to July 2018. Participants divided into a depression and a non-depression group according to the Korean version of the Center for Epidemiological Studies-Depression Scale (CES-D) score and were administered the following : a sociodemographic variables form (age, sex, academic background, occupation), the self-reporting test for adult ADHD (Adult Attention Deficit/Hyperactivity Disorder self-report scale-V 1.1; ASRS V1.1), and the Korean version of the Connors adult ADHD rating scale (K-CAARS). Descriptive statistical analysis, crossover analysis, t-tests, and Pearson's correlation coefficient were conducted on the data. Results : The coexistence rate of adult ADHD symptom was as high as 36.7% in patients with depression (p<0.001). In K-CAARS, the depression group (Inattention=1.80, Hyperactivity=1.92, Impulsivity=1.56, Self-concept=2.06) showed higher average scores on ADHD symptoms than the non-depressive group (Inattention=1.28, Hyperactivity=1.25, Impulsivity=1.09, Self-concept=1.42, p<0.001). Conclusions : This study confirmed that ADHD symptoms coexist in the depression group. When evaluating the symptoms of patients who complain of depression, it is suggested that they should be accurately diagnosed and appropriately treated with interest to the coexistence of ADHD symptoms and the possibility for ADHD diagnosis.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.2
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• pp.130-137
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• 2019

Objectives : When a patient who attempts suicide visits the emergency room, it is important that the departments of emergency medicine, internal medicine, and psychiatry communicate with each other and prioritize treatment. This study was conducted to verify the effectiveness of the multidisciplinary emergency consultation system (ECS) for drug intoxicated patients. Methods : We retrospectively analyzed the data from medical records prior to the ECS, from July 2017 to May 2018, and after the ECS, from July 2018 to May 2019, to verify the effectiveness of the system. Results : After the ECS, admission to open wards was significantly higher than to the intensive care units (χ²=8.567, p=0.014). In addition, the proportion of consultations to the department of psychiatry among patients admitted to other departments tended to increase (χ²=4.202, p=0.053), and the time required for consultation response decreased (Z=-2.031, p=0.042). As a result of the consultation, the proportion of the patients who had been transferred to the department of psychiatry was increased (χ²=4.692, p=0.043), and the time spent to transfer tended to decrease (Z=-1.941, p=0.052). Conclusions : After implementing the ECS for drug intoxicated patients, unnecessary intensive care unit admissions, consultation response time, and the time spent to transfer were reduced, and the rate of consultation referrals and transfer rates increased. This means that the multidisciplinary consultation system rapidly provided essential medical services to patients at lower medical costs.

• The Korean Journal of Quaternary Research
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• v.15 no.2
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• pp.101-109
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• 2001

The landscape changes at the Mujechi moors I and II during the last twenty two years were analysed using a tree ring analysis of pine trees, a distributional pattern of pine tree, an aerial photograph interpretation and a measurement of firebreak line. The analysis of aerial photographs(taken in 1978, 1988, 1998) indicates that the area of Mujechi moors I and II have gradually decreased. The decreased rate of moor area was relatively high, i.e.,-23.9 %(1978~1988) and -16.4 %(1998~1998) at the Mujechi moor I, but a little bit low, i.e., -2.6% (1978~1988) and -12.6 % (1998~1998) at the Mujechi moor II. However, dendrochronological analysis of pine trees at moors I and II shows that the appearance rates of pine trees per $100\textrm{m}^2$ at moor I and II were 0.28 and 0.57 respectively. And the number of younger pine trees(height is under 1.5m, DBH is less than 2.5 cm) invaded into moors are numbered eleven at the moor I, and ten at the moor II. This shows that the shift of a wetlands into a land was faster at the moor II than the moor I. The construction of a firebreak line and waterway along the moors I and II areas since the December, 1995, has diverted watershed flow and prohibited the runoff flow into the moors. The analysis of GIS suggests that the decreased watershed area were about $11,413.8\textrm{m}^2$(12.1 % of whole watershed area) at the moor I and $15,969.5\textrm{m}^2$(40.4 % of whole watershed area) at the moor II. The negative impact of firebreak line on the inflow of water into the moors I and II and destruction of vegetation along the firebreak line are noticeable from the field survey.

• Journal of the Korean association of regional geographers
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• v.6 no.3
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• pp.153-168
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• 2000

An estuarine marsh is semi -inclosed inlets, located between coastal and terrestrial environment. The sediment transport by river and tide through tidal river and vertical accretion by sediment accumulation are important processes in estuarine marsh. An analysis of the vertical accretion rate at various time scale is important work for understanding and managing coastal environments. The purpose of this study is to determin the spatial characteristics of vertical accretion rate in an estuarine marsh, Sunchon Bay, in the southern coastal region of Korean peninsula. The methods of analysis are sedimentation rate by individual tidal cycle, annual accretion rate, concentration of total suspended load in water column. Spatial characteristics of sedimentation rate by individual tidal cycle was investigated using 30 filter paper traps. Sedimentation rate by individual tidal cycle at levee edge was higher than that at back marsh. The sedimentation rate decreased with distance from estuarine front. Levee effect and proximity to the turbidity maximum zone result in a higher sedimentation rate in the levee edge. There is a weak relation-ships between tidal regime and sedimentation rate by individual tidal cycle. Spatial cahracteristics of annual accretion rate was investigared using 30 artificial marker plots. Annual accretion rate at back marsh($1.5{\sim}3.5cm/yr$) was higher than that at tidal river levee edge($0.8{\sim}3.0cm/yr$). Total suspended load (TSL) concentrations in water column also indicate this spatial characteristics of annual accretion rate. TSL concentration in water column leaving the vegetation part dramatically decreased. There is a very strong relationship between the concentration of suspended load and accretion rate. These results indicate that annual accretion rate is controlled by vegetation cover and proximity to the turbidity maximum zone. This difference of spatial characteristics of vertical accretion rate ar various time-scale was due to the fact that surface sediment of levee edge was eroded by tide and other factors. The major findings are as follows. First, the spatial characteristics of vertical accretion rate are different from various time-scale. Second, the major mechanism for the vertical accretion rate in this region is suspended load trapping by vegetation. Third, this region is primarily a depositional regime over the time-scale of the present data Fourth, this estuarine marsh is accreting at rates beyond other area.