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A Study on Contents of Vitamin K1 in Local Agricultural Products (지역농산물의 비타민 K1 함량 조사)

  • Lee, A Reum;Kim, Joo Hee;Park, Jae-Ho;Kim, Youngho;Hong, Eui Yon;Kim, Haeng-Ran;Choi, Youngmin;Lee, Junsoo;Eom, Hyun-Ju
    • The Korean Journal of Food And Nutrition
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    • v.29 no.3
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    • pp.301-306
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    • 2016
  • Vitamin K (phylloquinone) is an essential cofactor in the synthesis of active blood-clotting factors II, VII, IX and X. Deficiency of vitamin K leads to inadequate activity of these factors, resulting in bleeding. In this study, we investigated vitamin $K_1$ content of agricultural products that are widely and specifically grown in Korea including 9 leaves and vegetables, 16 fruits, and 11 cereals and specialty crops. Vitamin $K_1$ analysis of the agro-samples was by a validated, modified, reversed phase-HPLC method with fluorescence detection after post-column derivatization. The vitamin $K_1$ content ranged from 1.83 to $682.73{\mu}g$/100 g in leaves and vegetables, 0.17 to $28.22{\mu}g$/100 g in fruits, and ND to $279{\mu}g$/100 g in cereals and specialty crops. Among the 36 samples, high content of vitamin $K_1$ were found in Gugija (Lycium chinense Miller) leaves (average $682.73{\mu}g$/100 g) and Hansan ramie leaves (average $423.12{\mu}g$/100 g); however, mushroom, amaranth and Chinese artichoke showed no detectable levels. The results of ourstudy provide reliable vitamin $K_1$ content of Korean grown agricultural products that expand nutritional information and food composition database.

Package Atmosphere and Quality as Affected by Modified Atmosphere Conditions of Persimmon (Diospyros kaki. cv. Fuyu) Fruits ('부유' 단감의 MA포장 조건에 따른 포장기체조성 및 과실의 품질 변화)

  • Ahn, Gwang-Hwan;Song, Won-Doo;Park, Doo-Sang;Lee, Yeon;Lee, Dong-Sun;Choi, Seong-Jin
    • Korean Journal of Food Science and Technology
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    • v.33 no.2
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    • pp.200-204
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    • 2001
  • Persimmon (Diospyros kaki. cv. Fuyu) fruits were packaged under different conditions, and then stored at $0^{\circ}C$ for 21 weeks. The tried packages were heat-sealed bag of one fruit, heat-sealed bag of five fruits, and tie-sealed bag of five fruits, which used films of three different thickness (0.03 ㎜, 0.05 ㎜ and 0.06 ㎜). Throughout the storage, package free volume, package atmosphere and quality were measured. Package free volume decreased with time with higher rate for heat-sealed bags, in which close contact between fruit and the film was eventually reached in longer storage. However, tie-sealed bags maintained the levels of stabilized free volume. The rate of free volume decrease was faster with thinner film and larger bag size for the packs sealed by the same method. Package atmosphere covered $O_2$ concentration of $1.1{\sim}17.1%$ and $CO_2$ concentration of $1.1{\sim}8.3%$, $O_2$ concentration decreased during storage, whereas $CO_2$ increased. Thinner film package created the internal atmosphere of higher $O_2$ and lower $CO_2$ concentrations. Tie-sealed bags of 5 fruits in the films of 0.05 mm and 0.06 mm thickness maintained the equilibrated package atmosphere of $1.1{\sim}3.0%\;O_2$ and $4.0{\sim}5.5%\;CO_2$, which preserved the fruits best in terms of firmness and less physiological changes of flesh browning and peel browning. At five fruit heat-sealed bag in the films of 0.06 mm thickness with $CO_2\;8.3%$, flesh browning occurred at a high rate, whereas all treatments in the film of 0.03 mm thickness with high $O_2$ and relatively low $CO_2$ contents, flesh and peel browning rates were high.

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Electrochemical Characterization of Anti-Corrosion Film Coated Metal Conditioner Surfaces for Tungsten CMP Applications (텅스텐 화학적-기계적 연마 공정에서 부식방지막이 증착된 금속 컨디셔너 표면의 전기화학적 특성평가)

  • Cho, Byoung-Jun;Kwon, Tae-Young;Kim, Hyuk-Min;Venkatesh, Prasanna;Park, Moon-Seok;Park, Jin-Goo
    • Journal of the Microelectronics and Packaging Society
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    • v.19 no.1
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    • pp.61-66
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    • 2012
  • Chemical Mechanical Planarization (CMP) is a polishing process used in the microelectronic fabrication industries to achieve a globally planar wafer surface for the manufacturing of integrated circuits. Pad conditioning plays an important role in the CMP process to maintain a material removal rate (MRR) and its uniformity. For metal CMP process, highly acidic slurry containing strong oxidizer is being used. It would affect the conditioner surface which normally made of metal such as Nickel and its alloy. If conditioner surface is corroded, diamonds on the conditioner surface would be fallen out from the surface. Because of this phenomenon, not only life time of conditioners is decreased, but also more scratches are generated. To protect the conditioners from corrosion, thin organic film deposition on the metal surface is suggested without requiring current conditioner manufacturing process. To prepare the anti-corrosion film on metal conditioner surface, vapor SAM (self-assembled monolayer) and FC (Fluorocarbon) -CVD (SRN-504, Sorona, Korea) films were prepared on both nickel and nickel alloy surfaces. Vapor SAM method was used for SAM deposition using both Dodecanethiol (DT) and Perfluoroctyltrichloro silane (FOTS). FC films were prepared in different thickness of 10 nm, 50 nm and 100 nm on conditioner surfaces. Electrochemical analysis such as potentiodynamic polarization and impedance, and contact angle measurements were carried out to evaluate the coating characteristics. Impedance data was analyzed by an electrical equivalent circuit model. The observed contact angle is higher than 90o after thin film deposition, which confirms that the coatings deposited on the surfaces are densely packed. The results of potentiodynamic polarization and the impedance show that modified surfaces have better performance than bare metal surfaces which could be applied to increase the life time and reliability of conditioner during W CMP.

A COMPARATIVE STUDY ON THE CHEMICAL COMPOSITION AND MECHANICAL PROPERTIES OF FOUR LOW-GOLD-CONTENT DENTAL CASTING ALLOYS MANUFACTURED IN KOREA (한국산(韓國産) 치과주조용(齒科鑄造用) 저금함유합금(低金含有合金)의 조성(組成) 및 기계적(機械的) 성질(性質)에 관(關)한 비교연구(比較硏究))

  • Chang, Ik-Tae;Yang, Jae-Ho;Kim, Chang-Whe;Kim, Kwang-Nam;Lee, Sun-Hyung;Kim, Yung-Soo;Chang, Wan-Shik
    • The Journal of Korean Academy of Prosthodontics
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    • v.19 no.1
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    • pp.17-27
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    • 1981
  • This study was conducted to determine the chemical composition and the mechanical properties of four commercially available low gold-based crown and bridge alloy produced in Korea. Four dental casting gold-silver-palladium alloys, i.e., A, B, C and D (code of alloys) were selected for the evaluation of chemical composition, ultimate tensile strength, elongation. values and Vickers hardness. The chemical composition of test specimens was analyzed by both emission spectrography and wet gravitation method with a 1.5gm of low gold ingot. The tensile properties and Vickers hardness was determined with cast specimens treated in following three conditions; as-cast, softening heat treatment and hardening heat treatment. The tensile testing bars were cast in accordance with the model designed by Gettleman and Harrison (1969) which was modified from the A. D. A. Specification No. 14 for dental chromium-cobalt casting alloy. Nine tensile test specimens were made from a split silicone mold for each of the test alloys to the size of 2.5mm in diameter and a gauge length of 10mm. All four alloys were handled in accordance with conventional methods used in Type III gold alloys. Ultimate tensile strength and elongation were measured on an Instron Universal Tensile Testing Machine (Model 1125, Japan) operated at a crosshead rate of 0.1cm/min. Elongation values were measured using Digital Measuring Microscope (MS-152, FUSOH, Japan). Vickers hardness was determined with a Vickers Hardness Tester (Model VKH-l, Japan) at a 1.0kg load on a mounted tensile test specimen. The following results were obtained from this study; 1. All tested alloys were composed of Au, Ag, Pd, Cu, Zn and Fe in common. The composition rate of gold for all four alloys was found in the range of $42{\sim}47$ weight % as shown below. Alloy A; Au 45%, Ag 40.2%, Pd 5.76%, others 9.04%. Alloy B; Au 47.1%, Ag 29.03%, Pd 6.98%, others 16.92%. Alloy C; Au 45%, .Ag 26.9%, Pd 6.83%, others 21.07%. Alloy D; Au 41.8%, Ag 34.4%, Pd 6.95%, others 16.85%. 3. The ultimate tensile strength of the four alloys was in the range of $31{\sim}82kg/mm^2$. The test results were shown in the below order from the highest value; As-cast condition; D, B, C, A. Softening heat treament; B, C, D, A. Hardening heat treatment; D, B, C, A. 4. The test :results of the elongation rate for each alloy were in the range of $0.5{\sim}18%$. The test results were shown in the below order from the highest value; As-cast condition; A, D, B, C. Softening heat treatment; A, C, D, B. Hardening heat treatment; C, D, B, A. 5. Vickers hardness for each of the four alloys was in the range of $120{\sim}230$. The test results were shown in the below order from the highest value; As-cast condition; C, B, D, A Softening heat treatment; D, B, C, A. Hardening heat treatment; D, A, C, B. 6. There were no differences in the physical properties between as-cast condition and softening heat treatment.

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A Fluid Analysis Study on Centrifugal Pump Performance Improvement by Impeller Modification (원심펌프 회전차 Modification시 성능개선에 관한 유동해석 연구)

  • Lee, A-Yeong;Jang, Hyun-Jun;Lee, Jin-Woo;Cho, Won-Jeong
    • Journal of the Korean Institute of Gas
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    • v.24 no.2
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    • pp.1-8
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    • 2020
  • Centrifugal pump is a facility that transfers energy to fluid through centrifugal force, which is usually generated by rotating the impeller at high speed, and is a major process facility used in many LNG production bases such as vaporization seawater pump, industrial water and fire extinguishing pump using seawater. to be. Currently, pumps in LNG plant sites are subject to operating conditions that vary depending on the amount of supply desired by the customer for a long period of time. Pumps in particular occupy a large part of the consumption strategy at the plant site, and if the optimum operation condition is not available, it can incur enormous energy loss in long term plant operation. In order to solve this problem, it is necessary to identify the performance deterioration factor through the flow analysis and the result analysis according to the fluctuations of the pump's operating conditions and to determine the optimal operation efficiency. In order to evaluate operation efficiency through experimental techniques, considerable time and cost are incurred, such as on-site operating conditions and manufacturing of experimental equipment. If the performance of the pump is not suitable for the site, and the performance of the pump needs to be reduced, a method of changing the rotation speed or using a special liquid containing high viscosity or solids is used. Especially, in order to prevent disruptions in the operation of LNG production bases, a technology is required to satisfy the required performance conditions by processing the existing impeller of the pump within a short time. Therefore, in this study, the rotation difference of the pump was applied to the ANSYS CFX program by applying the modified 3D modeling shape. In addition, the results obtained from the flow analysis and the curve fitting toolbox of the MATLAB program were analyzed numerically to verify the outer diameter correction theory.

The Bibliographical Investigation of Sasang Constitution Diagnosis (사상체질(四象體質) 진단법(診斷法)의 문헌적(文獻的) 고찰(考察) - 외형(外形), 심성(心性), 증(證)을 위주(爲主)로 -)

  • Jung, Won-gyo;Kim, Jong-weon
    • Journal of Sasang Constitutional Medicine
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    • v.11 no.2
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    • pp.95-117
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    • 1999
  • 1. Purpose of study There are many Constitution theories. But, In the Sasang Constitutional medicine, the theory and the practice are connected systematically. So it has been used in Korea popularly. Lee Je-Ma suggested that the external form, the mind, the symptom are the criteria of Sasang constitution diagnosis at the Discourse on the Four Principle and the Discourse on the Identifying Four Constitutions. But The clinical importance study of three diagnostic criteria - the external form, the mind, the symptom - has never been studied. Therefore, there are many obstacles of using the three diagnostic criteria totally. And I think that it needs a study which we apply the three diagnostic criteria to practice and approve the clinical importance of one another. I classify and investigate the previous methods of Sasang constitution diagnosis by the three diagnostic criteria in this study. 2. Method of study I investigate the previous methods of Sasang constitution diagnosis bibliographically by Dongyi Soose Bowon, Journal of Constitutional medicine and other books. 3. Result of study (1) Study of the external form The Study of Ki-sang(氣像) and Sa-ki(詞氣) by experience and intuition was done previously, and study of imaginay formulation of each constitution by measuring Chae-hyung(體形) and yong-mo(容貌) has being done recently. (2) Study of the mind For the objectification of study and diagnosis, self-reporting questionnaire has been used. The ideal choice to determine an indivisual constitution, as far as questionnaire go, is to take results from both the modified version Sasang Pattern Identification Questionnaire and QSCCII. (3) Study of the symptom For the study of the symptom - constitution symptom and constitution symptom of disease - the study of principles, the clinical study of the type of disease and symptom, the study which the pathologic view of Oriental medicine apply the view of Sasang Constitutional medicine have been done. We must try to objectfy Sasang Constitutional disease.

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Microprogation And Environment Conditions Affecting On Growth Of In Vitro And Ex Vitro Of A. Formosanus Hay

  • Ket, Nguyen-Van;Paek, Kee-Yoeup
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2002.11a
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    • pp.29-30
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    • 2002
  • The goal of this research was to develop the effectiveness of in vitro culture method for A. formosanus and study the environment in vitro conditions affecting on growth. The first series of experiments were examined to investigate the response of three different basal media, MS (Murashige and Skoog, 1962), Knudson (KC; Knudson, 1946) and modified hyponex on growth and multiplication during in vitro culture. Multiple shoot proliferation was induced in shoot tip explants on Hyponex (H3) media supplemented with BA (1 mg1$\^$-1/) or TDZ (1-2 mg1$\^$-1/). Addition of activated charcoal (1%) to the TDZ containing medium promoted rapid shoot tip proliferation (11.1 shoots per explant) but the same medium had an opposite effect resulting in poor proliferation in the nodal explants. However, the regenerated shoots had slow growth rate and failed to elongate. This problem was overcome by transferring the shoot clumps to a hormone free H3 media supplemented with 2% sucrose and 0.5% activated charcoal. Using bioreactor culture for scaling up was also shown the best way for multiple shoot induction and growth of this plant. The second series of experiments was studied to investigate the effect of physical environment factors on growth of in vitro plantlets. The Anoectochilus formosanus plantlets were cultured under different air exchange rate (0.1, 0.9, 1.2h$\^$-1/), without sucrose or supplement 20g.1$\^$-1/ (photoautotrophic or photomixotrophic, respectively), and different photosynthesis photon flux (40, 80, 120 ,${\mu}$mol.m$^2$.s$\^$-1/- PPF). Under non-enrichment CO$_2$ treatment, slow growth was observed in photoautotrophical condition as compared with photomixotrophical condition on shoot height, fresh weigh and dry weight parameters; High air exchange (1.2.h-l) was found to be inadequate for plant growth in photomixotrophical condition. On the contrary, under CO$_2$, enrichment treatment, the plant growth parameters were sharply (visibly) improved on photoautotrophic treatments, especially on the treatment with air exchange rate of 0.9.h-1. The growth of plant in photoautotrophic condition was not inferior compared with photomixotrophic, and the best growth of plantlet was observed in treatment with low air exchange rate (0.9.h-1). Raising the PPF level from 80 to 120${\mu}$mol.m$\^$-2/.s$\^$-1/ decreased the plant height, particularly at 120${\mu}$mol.m$\^$-2/.s$\^$-1/ in photoautotrophic condition, fresh weight and dry weight declined noticeably. At the PPF of 120${\mu}$mol.m$\^$-2/,s$\^$-1/, chlorophyll contents lowed compared to those grown under low PPF but time courses of net photosynthesis rate was decreased noticeably. Light quality mainly affected morphological variables, changes of light quality also positively affected biomass production via changes in leaf area, stem elongation, chlorophyll content. Plant biomass was reduced when A. formosanus were grown under red LEDs in the absence of blue wavelengths compare to plants grown under supplemental blue light or under fluorescent light. Stem elongation was observed under red and blue light in the present experiment. Smaller leaf area has found under blue light than with other lighting treatments. Chlorophyll degradation was more pronounced in red and blue light compared with white light or red plus blue light which consequent affected the photosynthetic capacity of the plant. The third series of experiment were studied to investigate the effect of physical environment factors on growth of ex vitro plants including photosynthesis photon flux (PPF), light quality, growing substrates, electrical conductivity (EC) and humidity conditions. In the present experiments, response of plant on PPF and light quality was similar in vitro plants under photosynthesis photon flux 40${\mu}$mol.m,$\^$-2/.s$\^$-1/ and white light or blue plus red lights were the best growth. Substrates testing results were indicated cocopeat or peat moss were good substrates for A. formosanus growth under the greenhouse conditions. In case of A. formosanus plants, EC is generally maintained in the range 0.7 to 1.5 dS.m-1 was shown best results in growth of this plant. Keeping high humidity over 70% under low radiation enhanced growth rate and mass production.

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Leaching of Chromium, Copper and Arsenic in Soils and Rapid Identification of CCA-Treated Woods Using Modified PAN Stain (CCA 목재방부제 설치지역 토양의 크롬.구리.비소 분포와 PAN 지시약을 이용한 CCA 방부목의 현장 검출방법 개발)

  • Abdelhafez, Ahmed A.;Awad, Yasser M.;El-Azeem, Samy A.M. Abd;Kim, Min-Su;Ham, Kwang-Joon;Lim, Kyoung-Jae;Yang, Jae-E;Ok, Yong-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.1
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    • pp.60-67
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    • 2010
  • Although several studies have reported that Cr, Cu and As can leach from CCA-treated woods, few studies have been conducted on this topic in Korea. Therefore, this study was conducted to monitor Cr, Cu and As leaching from CCA-treated wood products and to develop a rapid identification method for CCA-treated wood products by using indicators such as PAN stain. Soil samples were collected at depths of 0-70 cm and wood samples were collected by thickness of wood layer. The soil and wood samples were then digested and analyzed for Cr, Cu and As concentrations using an atomic absorption spectrometer. The As and Cu concentrations decreased sharply with depth from 34.38 and 33.65 mg $kg^{-1}$ at 0-1 cm to 1.72 and 7.84 mg $kg^{-1}$ at 70 cm, respectively. In general, As was more mobile than Cr and Cu in the soil. For wood samples, the Cr, Cu and As concentrations were higher in the outer layer (0-0.5cm) than the inner layers (0.6-4.5cm). Evaluation of rapid identification methods revealed that 100% acetone with 0.1% PAN indicator was the best combination for detection of CCA-treated wood in the field.

The Mechanisms of Resistance to TNF in TNF-Sensitive Cancer Cells Transfected with TNF-$\alpha$ Gene Using Retroviral Vector (암세포에서 Retroviral Vector를 이용한 종양괴사인자 유전자 이입후 획득된 종양괴사인자 내성의 기전)

  • Lee, Hyuk-Pyo;Oh, Yeon-Mok;Yoo, Chul-Gyu;Kim, Young-Whan;Shim, Young-Soo;Han, Sung-Koo
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.3
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    • pp.547-558
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    • 1997
  • Background : Tumor necrosis factor(TNF) has been considered as an important candidate for cancer gene therapy based on its potent anti-tumor activity. However, since the efficiency of current techniques of gene transfer is not satisfactory, the majorities of current protocols is aiming the in vitro gene transfer to cancer cells and re-introducing genetically modified cancer cells to hoot. In previous study, it was shown that TNF-sensitive cancer cells transfected with TNF-$\alpha$ cDNA would become highly resistant to TNF. Understanding the mechanisms of TNF-resistance in TNF-$\alpha$ gene transfected cancer cells would be an important step for improving the efficacy of cancer gene therapy as well as for better understandings of tumor biology. This study was designed to evaluate the role of new protective protein synthesis in the acquired resistance to TNF of TNF-$\alpha$ gene transfected cancer cells. Method : We transfected TNF-$\alpha$ c-DNA to WEHI164, a murine fibrosarcoma cell line, using retroviral vector(pLT12SN(TNF)) and confirm the expression of TNF with PCR, ELISA, MIT assay. Then we determined the TNF resistance of TNF gene transfected cells(WEHI164-TNF) and the changes of TNF sensitivities after treatments with actinomycin D(transcription inhibitor) and cycloheximide ( translation inhibitor). Results : WEHI164 which was sensitive to TNF became resistant to TNF after being transfected with TNF-$\alpha$ gene and the resistance to TNF was partially reversed after treatment with actinomycin D, but not with cycloheximide. Conclusion : The acquired resistance to TNF after TNF-$\alpha$ gene transfection may be associated with synthesis of some protective proteins.

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An Analysis on Changing Pattern of Economic Active Population by Working Life Table for Korean Men (우리나라 노동생명표에 의한 노동력추이 분석)

  • 조진만
    • Korea journal of population studies
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    • v.13 no.2
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    • pp.1-18
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    • 1990
  • This is a study which attempt to analyze changing patierns of economic active popu-lation, t o estimato- future patterns, and exa- mine vartons problems arises by changing c ire u mst ances of t he labor force market in- clunging soici al, economic ic, heathl th and demoi-graph ic aspects. We have constructed series of wotking life table which are useful in syt uiolyioig the lirocess of growth and structural change of labor force. Work i ng life tables represent ihie life eyele of econrmic' activity in hi ypothetical cohorts, that is. gen-erat i on of men Sn bject at eat' b period ot f their lives th given ra to's o mor tali it y and of par-- tici pation in economic activities. The tabloes prot' ide measorues of the alvet'age he ng t able of economically aeti \- e life. and agespecific rates of en trannee' into and retirement from the hahn' force. In const routing working life tables, age-specific activity rates and life tabole popula- titoto which represents contemporary condi-tions of moortality in Korea au'e the basic' maltoerials. We have derived the age-specific rates foorm economically active population survey, whoich were conducted by the Bureau of Statistics, Economic Planning Borard of the Korean government. Working life tables are constructed for men wtable these materi- als in the year of 1970, 1980 and 1988 by a modified Wolfbein-Wool's method. Some of the findings may be summerized as follow : 1) A central part of constructing working life table is calculation of stationary' economic active population, which represents the number of men in the stationtary population extoected to be in the labor force at each age group in the life span. The stationary economic active population by age have generally a universal pattern, where they rise sharply in the early twenties, approach its' peak in the thirties decline thereafter. at first graolually and then more rapidly at an advanced age. Korean men show the same general pa ttern of age distribution of stationary eco-- nomic active population with sharp increase hegining from the age interval of 20 to 24, reaching to maximum level at older age. The population. however, presumably, increased substantially due to increaseing school atte endance rates. Another difference exiSts in the youngest age groups, that is the activity rate in the year of 1988 is lower than that of Japan. The table shows an analysis of changes in the age distrihution of labor force between 1970, 1980 and 1988. 2) It was shown an analysis of changes in the age distribution and cause of separation from labor force. The entrance rate to labor force has increased from 18~\5 persons to 299 persons per 1000 head of stationary population between that of 1980 than that of 1988 for Korean men in 20~24 age group. The entrace rate to labor force shows a rapid entrance appearance concentrated on the 15~24 age group. The separation rate from labor force by retirment in Korea in the year of 1988 shows a great difference of the about four times as much as that of Japan. 3) The functions of table illustrate the patterns of working life of males in Korea in 1970, 1980 and 1988. The average remaining number of economically active years, e at age 15 in 1988 is 46.39 which is 2.12 years of increase compared with that of at age 15 in 1970,1980 and 1988 are 43.90,44.27 and 46.39 respectively, showing steadily increase dur- ing the past double decade the increase in the length of economically active life various age may be considered to have come both from extention of general life expectancy and from increasing entrance rate to economic activity in high age that of working is far greater in 1988 than that of 1980. The gaps between expectation of life and average remaining years of economically active widened due to rapid improvement of mortality level in Ko- rea. This observation together with the population pressure by the appearance of a group of younger population implies that constant increase of economically inactive population among older age group.

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