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Distribution and Inter-annual Variation of Nutrients (N, P, Si) and Organic Carbon (DOC, POC) in the Equatorial Thermocline Ridge, Northeast Pacific (북동태평양 적도 Thermocline Ridge 해역에서 영양염(질소, 인, 규소)과 유기탄소(용존 및 입자)의 분포 특성 및 연간 변화)

  • Son, Ju-Won;Kim, Kyeong-Hong;Kim, Mi-Jin;Son, Seung-Kyu;Chi, Sang-Bum
    • Ocean and Polar Research
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    • v.33 no.1
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    • pp.55-68
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    • 2011
  • The distribution and inter-annual variation of nutrients (N, P, Si) and dissolved/particulate organic carbon were investigated in the equatorial thermocline ridge ($7^{\circ}{\sim}11.5^{\circ}N$, $131.5^{\circ}W$) of the northeast Pacific. From the Oceanic Nino Index and Multivariate ENSO Index provided by NOAA, normal condition was observed in July 2003 and August 2005 on the aspect of global climate/ocean change. However, La Ni$\~{n}$a and El Ni$\~{n}$o episodes occurred in July 2007 and August 2009, respectively. Thermocline ridge in the study area was located at $9^{\circ}N$ in July 2003, $8^{\circ}N$ in August 2005, $10^{\circ}N$ in July 2007, and $10.5^{\circ}N$ in August 2009 under the influence of global climate/ocean change and surface current system (North Equatorial Counter Current and North Equatorial Current) of the northeast Pacific. Maximum depth integrated values (DIV) of nutrients in the upper layer (0~100 m depth range) were shown in July 2007 (mean 21.12 gN/$m^2$, 4.27 gP/$m^2$, 33.72 gSi/$m^2$) and higher variability of DIV in the equatorial thermocline ridge was observed at $10^{\circ}N$ during the study periods. Also, maximum concentration of dissolved organic carbon (DOC) in the upper 50 m depth layer was observed in July 2007 (mean $107.48{\pm}14.58\;{\mu}M$), and particulate organic carbon (POC, mean $9.42{\pm}3.02\;{\mu}M$) was similar to that of DOC. Nutrient concentration in the surface layer increased with effect of upwelling phenomenon in the equatorial thermocline ridge and La Ni$\~{n}$a episode, which had formed in the central Pacific. This process also resulted in the increasing of organic carbon concentration (DOC and POC) in the surface layer. From these results, it is suggested that spatial and temporal variation of chemical and biological factors were generated by physical processes in the equatorial thermocline ridge.

Relationship Between the Catches and the Water Temperature of Tuna in the Pacific Ocean - The Operating Results of M . S #27 Cheng Rong at Eastern Fishing Ground of Tropical Rigion - (태평양 다랑어 어장의 어획량과 수온과의 관계-청룡 제27호의 열대해역 동부어장에서의 조업결과-)

  • 김광홍
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.32 no.1
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    • pp.24-32
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    • 1996
  • This paper described on relation between the catches of tuna and the distribution of water temperature of eastern fishing ground of Tropical region in the Pacific Ocean. The data of catches and water temperature used in this paper were based log book which # 27 CHENG RONG(Gross tonnage : 399 ton) had been worked eastern fishing ground(Lat : 09$^{\circ}$N- 14$^{\circ}$S, Long : 115$^{\circ}$- 149$^{\circ}$W)from January to October, 1991. The obtained result are as follows : 1. On the relation between the catches and the geographical distribution, bigeye tuna was higher catches at Lat 4$^{\circ}$- 9$^{\circ}$N, Long 135$^{\circ}$- 139$^{\circ}$W area in the equatorial counter current region where surface water temperature was range of 27.5$^{\circ}C$ to 27.9$^{\circ}C$, yellowfin tuna was higher catches at Lat 4$^{\circ}$- 9$^{\circ}$S, Long 145$^{\circ}$- 149$^{\circ}$W in the south equatorial current region where surface water temperature was range of 28.$0^{\circ}C$ to 28.4$^{\circ}C$ and albacore tuna was higher catches at Lat 10$^{\circ}$- 14$^{\circ}$S, Long 120$^{\circ}$- 124$^{\circ}$W area in the south equatorial current region where surface temperature was range of 26.5$^{\circ}C$ to 26.9$^{\circ}C$ 2. On the relation between catches and distribution of vertical water temperature, bigeye tuna was higher catches at the water temperature of 1$0^{\circ}C$ to 12$^{\circ}C$ on depth layer between 300m and 360m, yellowfin tuna was higher catches at the water temperature of 15$^{\circ}C$ to 19$^{\circ}C$ on depth layer between 180m and 280m and albacore tuna was higher catches at the water temperature of 12$^{\circ}C$ to 14$^{\circ}C$ on depth layer between 280m and 310m. Above the result, it seemed that bigeye tuna distributed deeper layer than yellowfin and albacore tuna.

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Studies on the Current Ideas and Institution of Natural Environmental Conservation in Japan -Policy and Institution of Open Space and Forest - (일본의 자연환경보전사조 및 관련제도의 변천에 관한 연구)

  • 김승환
    • Journal of the Korean Institute of Landscape Architecture
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    • v.17 no.1
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    • pp.1-16
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    • 1989
  • ^x As mentioned above, I consider the change of role that is related with Japanese thought of Natural Environmental Conservation, and I divide each part of periods into forest, farmland, open space, urban planning, environmental conservation etc. To summary the content of each period of Natural Environmental Conservation thought is as follows. 1) Previous period before formation(before 1919) In the previous period of Meiji, it could be said that the consciousness of the Natural Environmental Conservation was coming to existence. In this, so called, Natural Environmental Conservation, the thought of Forest Preservation was the main current and it was the thought of territorial integrity for the security of resource, the forestry conservancy and flood control in the forestry farmland. Since the age of Meiji, the theory of Natural Conservation appears from the theory of Japanese landscaping and systematic management about public parks was enforced, but the regular theory of Natural Environmental Conservation did not attain full growth. 2) The period of formation(1919~ 1954) In the period of formation, the base of Natural Environmental Conservation had been established. Parks and Open spaces were admitted as a public facilities in each city, and legislations which supported it had been continuously enacted and so on. In this period, the afforestation counter plan was emphasized on the side of territorial integrity. In the mountainous district. tree planting was emphasized to recover the forest which had been destroied by war. 3) The period of development(1955~ 1974) In the period of development, varied policies was institutionalized for the Natural Environmental Conservation. However, all sorts of development policy had performed simultaneously, thus development had complicated relation with preservation. But after 1970's the framework of system of Natural Environmental Conservation improvement was constituted to control the many kinds of development, and the spontaneous campaign of nature preservation by private lead was being taken root. This is the more progressive period. 4) The pried of root(after 1975) After the latter of 1970's, the role of Natural Environmental Conservation began to take root not in the direction of control but inducement, and, getting out of development - oriented policy, aimed at relation between human being and natural environment and the side of amenity of human environment. Besides, the current of Natural Environmental Conservation had been seperately progressed in the cities and forests. Since this period, it was the character that cities and forests began to be unified as 'amenity'space of man.

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Electrochemical Behavior of Tin and Silver during the Electrorecycling of Pb-free Solder (Sn-Ag-Cu) Waste (폐무연솔더(Sn-Ag-Cu)의 전해재활용 시 주석과 은의 전기화학적 거동 연구)

  • Kim, Min-seuk;Lee, Jae-chun;Kim, Rina;Chung, Kyeong-woo
    • Resources Recycling
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    • v.31 no.3
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    • pp.61-72
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    • 2022
  • We investigated the electrochemical behavior of Sn (93.0 %)-Ag (4.06 %)-Cu (0.89 %) during electrolysis of Pb-free solder waste to recover tin and silver. A thin strip of the solder waste produced by high-temperature melting and casting was used as a working electrode to perform electrochemical analysis. During anodic polarization, the current peak of an active region decreased with an increase in the concentration of sulfuric acid used as an electrolyte. This resulted in the electro-dissolution of the working electrode in the electrolyte (1.0 molL-1 sulfuric acid) for a constant current study. The study revealed that the thickening of an anode slime layer at the working surface continuously increased the electrode potential of the working electrode. At 10 mAcm-2, the dissolution reaction continued for 25 h. By contrast, at 50 mAcm-2, a sharp increase in the electrode potential stopped the dissolution in 2.5 h. During dissolution, silver enrichment in the anode slime reached 94.3% in the 1 molL-1 sulfuric acid electrolyte containing a 0.3 molL-1 chlorine ion, which was 12.7% higher than that without chlorine addition. Moreover, the chlorine enhanced the stability of the dissolved tin ions in the electrolyte as well as the current efficiency of tin electro-deposition at the counter electrode.

Application of SPS Code and analysis on status of Port State Control in Korea fishery training ship (어업실습선의 SPS Code 적용과 항만국통제 현황 분석)

  • RYU, Kyung-Jin;LEE, Yoo-Won;KIM, Seok-Jae;PARK, Tae-Gun;PARK, Tae-Seon;JO, Hyeon-Jeong;KIM, Hyung-Seok
    • Journal of Fisheries and Marine Sciences Education
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    • v.29 no.3
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    • pp.711-718
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    • 2017
  • This study identified application range of SPS Code(Special Purpose Ship Code) applied to fishery training ship in Korea, and proposed counterplan for port state control. The latest contents of relevant convention was verified, used APCIS of Tokyo MOU and EQASIS provided by EU to analyze the current condition and deficiencies of port state control of fishery training ship. As the result, the SPS code equal to passenger ship and cargo ship of SOLAS convention should be satisfied with fishery training ship, and must follow ISPS Code. As for the result of record of port state control, it was confirmed that 8 fishery training ships were inspected 76 times and pointed out with 411 deficiencies in Tokyo MOU nation. 75% of deficiencies were related to SOLAS convention, and 71 times of inspections were conducted in Japan. Because it is not free from the fishery training ship, there is a need for active corresponding and preparation by enhancing local cooperative system and sharing the Internet inspection background, and need to develop and implement in-depth internship program to improve port state control counter plan for the trainees.

Phase Changes during High Temperature Gas Nitriding of Nb Alloyed STS 444 Ferritic Stainless steel (Nb이 첨가된 STS 444 페라이트계 스테인리스강의 고온질화 열처리시 조직변화)

  • Kong, J.H.;Yoo, D.K.;Lee, H.W.;Kim, Y.H.;Sung, J.H.
    • Journal of the Korean Society for Heat Treatment
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    • v.20 no.6
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    • pp.323-328
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    • 2007
  • This study has been investigated the effect of high temperature gas nitriding (HTGN) heat treatment of STS 444 (18Cr-0.01Ni-0.01C-0.2Nb) ferritic stainless steel in an atmosphere of nitrogen gas at the temperature range between $1050^{\circ}C\;and\;1150^{\circ}C$. The surface layer was changed into martensite and austenite with the nitrides of NbCrN by HTGN treatment. Due to the precipitation of nitrides and matrensite formation, the hardness of the surface layer showed $400Hv{\sim}530Hv$. The nitrogen concentration of the surface layer appeared as 0.05%, 0.12% and 0.92%, respectively, at $1050^{\circ}C,\;1100^{\circ}C\;and\;1150^{\circ}C$. When the nitrogen is permeated from surface to interior, Nb and Cr, which have strong affinities with nitrogen, also move from interior to surface. Therefore it is considered that this counter-current of atoms promotes the formation of NbCrN at the surface layer.

A Study for the Efficiency Analysis on Big Deals of Electronic Journal (전자저널 빅딜계약의 효율성 분석 연구)

  • Kim, Jeong-Hwan;Lee, Eung-Bong
    • Journal of the Korean Society for Library and Information Science
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    • v.47 no.4
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    • pp.187-210
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    • 2013
  • The consumption through e-journal consortia makes researchers locate and use academic resources and information extensively with comparatively cheap costs. This study analyzed and investigated substantive benefits of the big deal contracts for e-journal subscriptions in terms of efficient information use. In other words, this study compare concretely the differences in efficiency of using information between large-size institutions and small-size institutions who participate in the e-journal big deal contracts. This study suggests solutions for the problems which occur persistently and repeatedly in the big deal and new counter plans which can replace the current methods of big deal contracts in a long-term perspective by revealing the gaps of acquiring and using information by the size of participating institutions.

Progress on Phytochemical and Atopic Dermatitis-related Study of the Root of Lithospermum erythrorhizon (자초 뿌리의 함유성분 및 아토피피부염 관련 연구현황)

  • Ju, Ji-Hoon;Cho, Hyun-Hwan;Lee, Yong-Sup
    • Korean Journal of Pharmacognosy
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    • v.41 no.2
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    • pp.73-88
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    • 2010
  • Traditionally, the root of Lithospermum erythrorhizon Sieb. et Zucc(L.E) has been used as efficacious therapy for inflammation, burns, frostbite and skin ailments (e.g eczema and psoriasis). It contains isohexenylnaphthoquinone derivatives (shikonin and its esters) and furylhydroquinones (shikonofurans) in lipophilic fractions and caffeic acid oligomers (rosmarinic acid, lithospermic acid B) in polar fractions. Recently, new preparative isolation and analysis procedures of shikonin along with its oligomers from the extract of L. erythrorhizon by the combination of high-speed counter-current chromatography with high-performance liquid chromatography-diode array detection have also been introduced. Although there have been many reports on the wound healing, antiinflammatory, and anticancer effects, the research on the effects of anti-atopic dermatitis of the root of L. erythrorhizon were relatively scarce. However, in recent years, new information gathered from research efforts, on the anti-atopic dermatitis properties of the extract or constituents of L. erythrorhizon has been accumulated. In this paper, the findings and advance on the in vitro and in vivo activities of L. erythrorhizon and its constituents especially focused on antiinflammatory and anti-atopic dermatitis effects are summarized. The phytochemical constituents of L. erythrorhizon or its tissue cultures are also presented. Although there are few to verify or refute its activity in human, one result of clinical study of the extract of L. erythrorhizon on the atopic dermatitis patients was introduced to assess the possibility of its clinical use. The reported mechanisms of action and in vivo pharmacological studies in different animal models for the various types of extracts or constituents of L. erythrorhizon are supportive of its therapeutic potential or dietary supplement, however, more evidence from clinically relevant models, as well as systemic studies on the active constituents or the various types of standardized extracts at the cellular and molecular level, are required.

An Unexpected Improvement of the Symptom from Herniated Intervertebral Disc during Trial of Spinal Cord Stimulation for the Post-herpetic Neuralgia -A case report- (대상포진 후 신경통에 시행된 실험적 척수자극술시 예측치 못한 추간판 탈출증 증상의 개선 -증례 보고-)

  • Ahn, Jae-Seok;Han, Seok-Hee;Kim, Tae-Hyeong;Park, Hahck-Soo;Lim, Young-Jin;Lee, Sang-Chul
    • The Korean Journal of Pain
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    • v.14 no.1
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    • pp.110-113
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    • 2001
  • In controlling chronic intractable pains, the current therapeutic methods used are exercise, over the counter medication, cognitive-behavioral therapy, opioid medication, neural blockade, operation, etc., spinal cord stimulation being the last resort. Spinal cord stimulation was initiated when Shearly and others clinically tested the Gate control theory of Melzack and Wall. This had triggered the advancement of theoretic research on the mechanism and hardware necessary and has resulted in an accumulation of clinical experiences. This is known to be effective for treating sympathetic pain, arachnoiditis, failed back pain syndrome, radiculopathy, peripheral vascular disease, phantom limb syndrome, post-herpetic neuralgia, peripheral neuropathy, and angina pectoris. This report describes our experience in experimental spinal cord stimulation in patients with simultaneous post-herpetic neuralgia and herniated intervertebral disc. There wasn't any improvement in the post-herpetic neuralgia but the symptoms of a herniated intervertebral disc was much ameliorated. This was quite an unexpected result. The patient's back pain returned when the stimulation stopped.

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Study on the Separation of MAs from HLLW and Their Extraction Behavior Using New Extractants of Amido Podand

  • An, Ye-Guo;Luo, Fang-Xiang;Zhu, Zhi-Xuan;Zhang, Xiang-Ye;Zhu, Wen-Bin
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.02a
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    • pp.245-256
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    • 2004
  • The extraction of three kinds of amido podands, N,N,N'N'-tetrabutyl-3-oxa-pentanedi- amide (TBDGA), N,N,N'N'-tetra-isobutyl-3-oxa-pentanediamide(TiBDGA) and N,N,N'N'-tetra- butyl-3,6-dioxa-oct-anediam- ide(TBDOODA) on U(VI),Pu(IV), Am(III), Eu(III) and other metal ions is studied in nitric acid solutions. 40%octanol-kerosene is chosen as diluents to eliminate third phase and emulsion. TBDGA and TiBDGA show extraction selectivity to An(III) and Ln(III) much higher than to U(VI) and Pu(IV). Fe, Ru and Mo is poorly extracted by the three kinds of amid podands in 2~3mol/L $HNO_3$ solutions. Aiming to eliminate interface crude when using simulated HLLW solution in the system of 0.2mol/L TBDGA/Octanol+kerosene, acetohydroxyamic acid was adapted. Distribution ratio of zirconium was decreased when adding acetohydroxyamic acid in aqueous solution, and interface crude disappeared as mixing extractant with HLLW. The counter-current extraction test is carried out in a set of miniature mixer-settler, with 0.2mol/L TBDGA/ 40% octanol-kerosene as extractant to separate U(VI), Pu(IV), Am(III) and Eu(III) from simulated high level liquid waste(HLLW) solution. In battery A, lanthanides and actinides are coextracted into organic phase with the recovery of 99.98% for U(Ⅵ), >99.99% for Pu(IV), and >99.99% for Am(III) and Eu(III) respectively. In battery R1, 99.99% U, 86.2% Pu and a part of Am or Eu are stripped into aqueous phase by 0.2mol/L acetohydroxyamic acid (AHA) in 0.01mol/L $HNO_3$ solution. In battery $R_2$, Am, Eu and remained Pu are completely back-extracted by 0.2mol/L AHA. This separation process contains no salt reagent, and it is not necessary to dilute HLLW feed.

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