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Study on the Characteristics of Gas Hydrate Layers Distributed in the Southern Ulleung Basin, the East Sea (동해 울릉분지 남부해역에 분포하는 가스 하이드레이트층의 특성 연구)

  • Huh Sik;Yoo Hai-Soo;Kim Han-Joon;Han Sang-Joon;Lee Yong-Kuk
    • The Korean Journal of Petroleum Geology
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    • v.10 no.1_2 s.11
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    • pp.18-22
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    • 2004
  • To identify and interpret the distribution and the characteristics of the gas hydrate layers in the Ulleung Basin, we have surveyed and gathered the multi-channel seismic data, Chirp sub-bottom profiler, SeaBeam and 12 m piston core samples since 1996. In previous works, high-resolution seismic profiles showed acoustic anomalies such as acoustic void, acoustic turbidity and pock mark which indicate the presence of gas-charged sediments. The patterns of horizontal degassing cracks originated from free methane expansion is the strong indicator of shallow gas-charged sediments in the core samples. The observation of submarine slides and slumps from destabilizing the sediments in the southern part of the Ulleung Basin may also point out that the gas had been released from gas hydrate dissociation during lowstand of sea level. The multi-channel seismic data show BSR, blanking and phase reversal. The gas hydrate layers above which large-scale shallow gases are distributed exist at the depth of about 200 m from the sea-floor with water depth of 2,100 m. From the interpretation of seismic sections in the southern Ulleung Basin, gas hydrate layers occur in the Pleistocene-Holocene sediments. These gas-charged sediments, acoustic anomalies and BSR may be all related to the existence of gas hydrate layers in the study area.

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Spectroscopic Comparison of Photo-oxidation of Outside and Inside of Hair by UVB Irradiation (자외선B 조사에 의한 모발 외부와 내부의 광산화에 관한 분광학적 비교)

  • Ha, Byung-Jo
    • Applied Chemistry for Engineering
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    • v.31 no.2
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    • pp.220-225
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    • 2020
  • Hair is made of proteins containing various amino acids. Ultraviolet (UV) radiation is believed to be responsible for the most damaging effects of sunlight, and also plays an important role in hair aging. The purpose of this study was to investigate the changes in morphological and chemical structures after ultraviolet B (UVB) irradiation of human hair. The UVB-irradiated hair showed characteristic morphological and structural changes, compared to those of the normal hair. The result from a scanning electron microscope (SEM) equipped with an energy dispersive X-ray diffractometer (EDX) showed that the scale of UV-irradiated hair appeared to be rough and the amount of oxygen element was higher than that of the normal hair. Fluorescence and three dimensional (3D) topographical images were obtained by a confocal laser scanning microscope (CLSM). In 3D images, the green emission intensity of normal hair was much higher than that of fluorescing UVB-irradiated hair. The intensity of green emission reflects the intrinsic fluorescence of hair protein. Also, a fluorescent imaging method using fluorescamine reagent was used to identify the free amino groups resulting from a peptide bond breakage in UVB-irradiated hair. Strong blue fluorescence of UVB-irradiated hair, which indicates a very high level of amino groups, was observed by CLSM. Therefore, the fluorescamine as an extrinsic fluorescence could provide a useful tool to identify the peptide bond breakage in UVB-irradiated hair. Infrared image mapping was also employed to assess the cross-sections of normal and UVB-irradiated specimens to examine the oxidation of disulfide bonds. The degree of peak areas with strong absorbance for the disulfide mono-oxide was spread from the outside to the inside of hair. The spectroscopic techniques used alone, or in combination, launch new possibilities in the field of hair cosmetics.

A Study on Causes of Franchisee's Conflict in Distribution Channel of small and middle sized Franchise Industry (중소형 프랜차이즈 유통시스템에서 가맹점의 갈등에 관한 질적 연구 - 토대이론 접근법을 활용하여-)

  • Jeon, Ta-sik
    • Journal of Distribution Science
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    • v.4 no.2
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    • pp.21-40
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    • 2006
  • Small and middle sized Franchise system channels experience conflicts because of constant interaction between franchiser and franchisee. However, it is rarely that attempt has been made to identify causes of conflicts in distribution of franchise industry. The purpose of this study was to explore cause of conflicts from the franchisee. For the study, data were collected from the owner or the shop-manager with a contractor in franchise systems. By means of in-depth interviews with multiple informants, their statement was analyzed qualitatively. From analysis of the resulting data, the causes of conflicts were associated with two broad sets, attitudinal and structural differences between franchisers and franchisees. First, attitudinal sources of conflict were identified as perception of subordinated relationships between channel members, delayed announcement on order changes, difficulties in communication by doing irresponsible behavior, different expectations between channel members in market territory and lack of consistent-supporting. Second, structural sources of conflict involved unilateral decision on interior, payment method, unreasonable delivery issue, treat franchisee with discrimination by the sales, in controlling against free management. There are limitations on generalization due to the results based on interview, but this study will be a useful exploratory step before designing a large scale survey.

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Evaluation of Quality Properties of Gamma-irradiated Freeze-dried Fruits (감마선 조사에 따른 동결건조과일의 품질 특성 평가)

  • Choi, Soo-Jeong;Yoon, Young-Min;Han, In-Jun;Kim, Jae-Kyung;Park, Jong-Heum;Lee, Ju-Woon;Lyu, Eun-Soon;Yook, Hong-Sun;Kim, Jae-Hun;Song, Beom-Seok
    • Journal of Radiation Industry
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    • v.6 no.4
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    • pp.299-304
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    • 2012
  • The quality properties of freeze-dried apples, pears, strawberries and pineapples gamma-irradiated at 0, 1, 2, 3, 4, and 5 kGy were evaluated to develop germ-free products for immuno-compromised patients. The initial count of total aerobic bacteria in non-irradiated apples, pears, strawberries and pineapple was 2.5, 3.1, 2.6, and $3.2{\log}\;CFU{\cdot}g^{-1}$, respectively. Microorganisms were not observed in apples after 1 kGy, in pears and strawberries after 4 kGy, and in pineapples at 5 kGy within a detection limit of $10{\log}\;CFU{\cdot}g^{-1}$. In addition, the sterilization of each sample was confirmed at the same dose. The score for the overall acceptance of freeze-dried fruit irradiated at a sterilization dose was 5.5 for apples, 4.1 for pineapples, and 4.0 for the other fruits, whereas that of non-irradiated control sample was 5.6 for apples, 5.2 for pears, and 5.8 for strawberries and pineapples with a 7-point scale. As a result, gamma irradiation of 1 kGy for apples, 4 kGy for strawberries and pears, and 5 kGy for pineapples is sufficient to sterilize each freeze-dried fruit with acceptable sensory properties.

Relief of Chronic Posterior Neck Pain Depending on the Type of Forest Therapy: Comparison of the Therapeutic Effect of Forest Bathing Alone Versus Forest Bathing With Exercise

  • Kang, Boram;Kim, Taikon;Kim, Mi Jung;Lee, Kyu Hoon;Choi, Seungyoung;Lee, Dong Hun;Kim, Hyo Ryoung;MA, Byol Jun;Park, Seen Young;Lee, Sung Jae;Park, Si-Bog
    • Annals of Rehabilitation Medicine
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    • v.39 no.6
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    • pp.957-963
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    • 2015
  • Objective To compare the pain-reducing effect of forest bathing alone versus forest bathing in combination with stretching and strengthening exercises in patients with chronic posterior neck pain. Methods Sixty-four subjects with posterior neck pain that had lasted more than 3 months were enrolled. They were randomly divided into a forest bathing alone (FBA) group and a forest bathing with exercise (FBE) group; each group included 32 subjects. All subjects from both groups walked every morning in the forest for about 2 hours for 5 days. In the afternoon, the FBE group did a stretching and strengthening exercise for about 4 hours; the FBA group had free time in the woods. Visual analog scale (VAS) on one day, VAS over the previous week, neck disability index (NDI), EuroQol 5D-3L VAS (EQ VAS) and index (EQ index), McGill pain questionnaire (MPQ), the number of trigger points in the posterior neck region (TRPs), and the range of motion of the cervical spine were evaluated on the first and last day of the program and compared between the two groups. Results The number of TRPs were significantly reduced in the FBE group compared with the FBA group (p=0.013). However, the other scales showed no significant difference between the two groups. Conclusion When patients with chronic posterior neck pain underwent a short-term forest bathing (less than 7 days) program, FBE was more effective in the reduction of the number of TRPs than FBA. However, all other pain measurement scales we evaluated showed no statistically significant difference between the two protocols.

A Study on Transient Operation Characteristics of 30kW Scale CVCF Inverter based Micro-grid (30kW급 CVCF 인버터 기반 Micro-grid의 구현 및 과도상태 운용특성에 관한 연구)

  • Lee, Hu-Dong;Choi, Sung-Sik;Ferreira, Marito;Park, Ji-Hyun;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.10
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    • pp.18-25
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    • 2019
  • Recently, micro-grids based on a CVCF inverter have been replacing diesel generators to reduce CO2 emissions in island areas with the increase of renewable energy sources. Stable operation methods are also being researched. These micro-grids may cause energy sinking if the total output of renewable energy sources is larger than the total customer loads. In the case of energy sinking, the voltage of a CVCF battery could rapidly increase according to the condition of SOC, and blackout could occur in the micro-grid due to the operation of a protection device in a CVCF inverter. Therefore, this paper analyzes the operation characteristics of a CVCF-inverter-based micro-grid when energy sinking occurs and proposes a transient operation strategy to prevent shut-down of the CVCF inverter. A test device of a 30-kW CVCF-inverter-based micro-grid was implemented, and the transient operation characteristics for the energy sinking phenomenon are presented. The simulation results confirm that blackout can be properly prevented according to the conditions of SOC and voltage in a CVCF battery.

Investigation of the Molecular Diagnostic Market in Animals (동물 분자 진단 시장의 동향)

  • Park, Chang-Eun;Park, Sung-Ha
    • Korean Journal of Clinical Laboratory Science
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    • v.51 no.1
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    • pp.26-33
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    • 2019
  • Recently, the rapid growth of the companion animal market has led to the development of animal disease diagnosis kits. Therefore, the utility of the introduction of biomarkers for the development of animal molecular diagnostics is being reevaluated. A good biomarker should be precise and reliable, distinguish between normal and diseased states, and differentiate between different diseases. Recently reported genetic markers, tumor markers (cell free DNA, circulating tumor cells, granzyme, and skin tumors), and others (brucellosis, programmed death recovery-1, symmetric dimethylarginine, periostin, and cysteinyl leukotrien) have been developed. The biomarkers are used for risk prediction or for the screening, diagnosis, and monitoring of disease progression. The most important criteria for related biomarkers are disease specificity. Many potential biomarkers have emerged from laboratory and test studies, but they have not been validated in independent or large-scale clinical studies. Candidate biomarkers evaluate disease associations, verify the effectiveness of biomarkers for early detection and disease progression, and incorporate them into humans and animals. In the future, it will be necessary to reevaluate the utility of well-structured biomarker-based research and study the development of kits that can be used in on-site tests in accordance with the trends introduced in the diagnosis of animal diseases.

Surgical Treatment of Chronic Tophaceous Gout in the 1st Metatarso-Phalangeal Joint (족부 제 1중족 족지 관절에 발생한 만성 결절성 통풍의 수술적 치료)

  • Lee, Tae-Hun;Nam, Il-Hyun;Ahn, Gil-Yeong;Lee, Yeong-Hyeon;Lee, Yong-Sik;Choi, Young-Deuk;Lee, Hee-Hyung
    • Journal of Korean Foot and Ankle Society
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    • v.22 no.4
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    • pp.156-160
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    • 2018
  • Purpose: Chronic tophaceous gout is a painful and disabling inflammatory disease. Surgical treatment for chronic tophaceous gout is very difficult with many complications. This study evaluated the efficacy of shortening scarf osteotomy on the treatment of chronic tophaceous gout in the 1st metatarso-phalangeal (MTP) joint. Materials and Methods: From January 2006 to December 2015, 14 patients (19 cases) who underwent axial shortening scarf osteotomy for chronic tophaceous gout were reviewed. All patients were male. The average age at the time of surgery was 59.6 years (42~66 years). The minimum follow-up was 24 months. Total removal of the tophi mass with the adhered medial capsule of the 1st MTP joint was attempted. Axial shortening scarf osteotomy was done on the 1st metatarsal shaft. The visual analogue scale (VAS) for pain and the American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score was assessed preoperatively and postoperatively. The range of motion (ROM) of the 1st MTP joint was also compared pre- and postoperatively. Results: The average size of the extracted tophaceous mass was 32 mm. The mean amount of the length of metatarsal shortening was 4.9 mm. The mean ROM of the 1st MTP joint was improved from $30.4^{\circ}$ to $62.3^{\circ}$. The mean AOFAS forefoot score improved from 51.4 to 86.6 points. The mean VAS for pain improved from 4.6 to 0.3 points. Conclusion: The axial shortening scarf osteotomy used on chronic tophaceous gout could reconstruct the 1st MTP joint with an improved ROM and was free of pain. Axial shortening scarf osteotomy is suggested as a useful and effective method for the treatment of chronic tophaceous gout.

Clinicopathological Features of Primary Solitary Spinal Cord Tumors in Pediatric Patients : A 32-Year Single Institution Experience

  • Choi, Ho Yong;Kim, Kyung Hyun;Cho, Byung-Kyu;Wang, Kyu-Chang;Phi, Ji Hoon;Lee, Ji Yeoun;Park, Sung-Hye;Kim, Seung-Ki
    • Journal of Korean Neurosurgical Society
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    • v.64 no.4
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    • pp.592-607
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    • 2021
  • Objective : Few studies exist on primary spinal cord tumors (PSCTs) in pediatric patients. The purpose of this study was to perform descriptive analysis and detailed survival analysis for PSCTs. Methods : Between 1985 and 2017, 126 pediatric patients (male : female, 56 : 70) with PSCTs underwent surgery in a single institution. We retrospectively analyzed data regarding demographics, tumor characteristics, outcomes, and survival statistics. Subgroup analysis was performed for the intramedullary (IM) tumors and extradural (ED) tumors separately. Results : The mean age of the participants was 6.4±5.04 years, and the mean follow-up time was 69.5±46.30 months. The most common compartment was the ED compartment (n=57, 45.2%), followed by the IM (n=43, 34.1%) and intradural extramedullary (IDEM; n=16, 12.7%) compartments. Approximately half of PSCTs were malignant (n=69, 54.8%). The most common pathologies were schwannomas (n=14) and neuroblastomas (n=14). Twenty-two patients (17.5%) died from the disease, with a mean disease duration of 15.8±15.85 months. Thirty-six patients (28.6%) suffered from progression, with a mean period of 22.6±30.81 months. The 10-year overall survival (OS) rates and progression-free survival (PFS) rates were 81% and 66%, respectively. Regarding IM tumors, the 10-year OS rates and PFS rates were 79% and 57%, respectively. In ED tumors, the 10-year OS rates and PFS rates were 80% and 81%, respectively. Pathology and the extent of resection showed beneficial effects on OS for total PSCTs, IM tumors, and ED tumors. PFS was affected by both the extent of removal and pathology in total PSCTs and ED tumors; however, pathology was a main determinant of PFS rather than the extent of removal in IM tumors. The degree of improvement in the modified McCormick scale showed a trend towards improvement in patients with IM tumors who achieved gross total removal (p=0.447). Conclusion : Approximately half of PSCTs were malignant, and ED tumors were most common. The most common pathologies were schwannomas and neuroblastomas. Both the pathology and extent of resection had a decisive effect on OS. For IM tumors, pathology was a main determinant of PFS rather than the extent of removal. Radical excision of IM tumors could be a viable option for better survival without an increased risk of worse functional outcomes.

Evaluation of the DCT-PLS Method for Spatial Gap Filling of Gridded Data (격자자료 결측복원을 위한 DCT-PLS 기법의 활용성 평가)

  • Youn, Youjeong;Kim, Seoyeon;Jeong, Yemin;Cho, Subin;Lee, Yangwon
    • Korean Journal of Remote Sensing
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    • v.36 no.6_1
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    • pp.1407-1419
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    • 2020
  • Long time-series gridded data is crucial for the analyses of Earth environmental changes. Climate reanalysis and satellite images are now used as global-scale periodical and quantitative information for the atmosphere and land surface. This paper examines the feasibility of DCT-PLS (penalized least square regression based on discrete cosine transform) for the spatial gap filling of gridded data through the experiments for multiple variables. Because gap-free data is required for an objective comparison of original with gap-filled data, we used LDAPS (Local Data Assimilation and Prediction System) daily data and MODIS (Moderate Resolution Imaging Spectroradiometer) monthly products. In the experiments for relative humidity, wind speed, LST (land surface temperature), and NDVI (normalized difference vegetation index), we made sure that randomly generated gaps were retrieved very similar to the original data. The correlation coefficients were over 0.95 for the four variables. Because the DCT-PLS method does not require ancillary data and can refer to both spatial and temporal information with a fast computation, it can be applied to operative systems for satellite data processing.