• Title/Summary/Keyword: Mass changes

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Hydrographic Analysis of Surface Water Using Radium Isotopes Signature in the East and South China Sea in Summer (여름철 동중국해 및 남중국해 표층수의 Ra 동위원소를 이용한 수계분석)

  • Yang, Han-Soeb;Lee, Tong-Sup
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.4
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    • pp.305-311
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    • 1999
  • This study aims to decipher surface water mass interaction in summer in the South China Sea and East China Sea by radium isotope distribution pattern. Salinity and activity ratio of radium ($^{228}Ra/^{226}Ra$) showed gradual changes, which were adequate to apply simple two end-member mixing between Kuroshio surface water and Changjiang Dilute Water for the East China Sea and the former and Nearshore Diluted Watermass (NDW) for the South China Sea. Two tracer methods, salinity and Ra isotope ratio, were compared for East China Sea. Results showed remarkable consistency for waters near Kuroshio, however, discrepancy were noticeable after Tsushima Warm Current branching. Mixing with subsurface waters may cause the discrepancy. When mixed with subsurface waters, salts and radium isotope ratio are expected to be biased in opposite direction, i. e. prone to underestimate the fraction of less saline water in the case of salts and vice versa for Ra isotope ratio. Taking the mean values of two different results seems more realistic to estimate fraction of end-members.

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Autologous Fat Graft in the Reconstructed Breast: Fat Absorption Rate and Safety based on Sonographic Identification

  • Kim, Hong Youl;Jung, Bok Ki;Lew, Dae Hyun;Lee, Dong Won
    • Archives of Plastic Surgery
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    • v.41 no.6
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    • pp.740-747
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    • 2014
  • Background Autologous fat graft has become a useful technique for correction of acquired contour deformity in reconstructed breasts. However, there remains controversial regarding the efficacy and safety of the practice for reconstructive breast surgery. Methods A retrospective review was performed on 102 patients who had secondary fat grafting after breast reconstruction. Fat harvest, refinement and injection were done by Coleman's technique. All patients were followed up postoperatively within 1 month and after 6 months including physical examination and ultrasonography. In 38 patients, the reabsorption rate was calculated by serial changes of thickness between skin and pectoral fascia in the ultrasonic finding. Locoregional recurrence rate was compared with control group of 449 patients who had breast reconstruction without fat graft in the same time period. Results Average 49.3 mL fat was injected into each breast. The most common location of fat graft was upper pole, followed by axilla, lower and medial breasts. During 28.7 months of average follow-up period, 2.9% of total patients had symptoms of palpable mass on fat graft side and ultrasonography identified fat necrosis and cyst formation in 17.6% of the patients. Calculated fat reabsorption rate was 32.9%. Locoregional recurrence was occurred in 1 patient (0.9%) and the rate was not different significantly with control group (2%). Conclusions Although further studies are required to provide surgeons with definitive guidelines for the implementation of fat grafting, we propose autologous fat graft is an efficient and safe technique for secondary breast reconstruction.

A Study on the Mining Method for Limestone Mines with Less Environmental Hazards (환경오염 저감을 위한 석회석 광산개발방안에 대한 연구)

  • 임한욱;김재동;백환조
    • Tunnel and Underground Space
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    • v.10 no.1
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    • pp.80-91
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    • 2000
  • Open cut mining of limestone is generally considered to be more advantageous than underground mining in recovery, grade control, economics, and safety, but it causes substantial environmental pollutants such as ground vibration, noise, dust. It also changes ground surface and may destroy vegetation. The Halla limestone mine which lies adjacent to Baikdu mountains range is selected for a model study. To reduce environmental hazards, and to conserve original surface and woods, both open cut and underground mining methods must be adopted. In case of sub-level sloping. a unit block of 87m high, 70m wide, and 100∼l20m long is suggested with an estimated overall recovery of 42%. Some suggestions to reduce the environmental hazards are also included. The followings must be considered in determining the degree of fragmentation; the discontinuity conditions in the rock mass and the charge concentration both at the bottom and column of the hole. In addition to adopting a barrier wall for reducing environmental hazards, the probable production from underground mining is also discussed.

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Development of new integrated particle tracking techniques combining the numerical method, semi-analytical method, and analytical method (수치, 해석적, 준 해석적 및 해석적 방법을 통합한 새로운 입자추적기술 개발)

  • Suk, Hee-Jun
    • Journal of Soil and Groundwater Environment
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    • v.13 no.6
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    • pp.50-61
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    • 2008
  • In this study, new integrated particle tracking algorithm was developed to reduce the inherent problem of Eulerian- Lagrangian method, or adverse effect of particle tracking error on mass balance error. The new integrated particle tracking algorithm includes numerical method, semi-analytical method, and analytical method which consider both temporal and spatial changes of velocity field during time step. Detail of mathematical derivations is well illustrated and four examples are made to verify through the comparison of the new integrated particle tracking with analytical solution or Runge-Kutta method. Additionally, It was shown that the there is better superiority of the new integrated particle tracking algorithm over other existing particle tracking method such as Lu's method.

A Study on Pressure Distribution for Uniform Polishing of Sapphire Substrate

  • Park, Chul jin;Jeong, Haedo;Lee, Sangjik;Kim, Doyeon;Kim, Hyoungjae
    • Tribology and Lubricants
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    • v.32 no.2
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    • pp.61-66
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    • 2016
  • Total thickness variation (TTV), BOW, and surface roughness are essential characteristics for high quality sapphire substrates. Many researchers have attempted to increase removal rate by controlling the key process parameters like pressure and velocity owing to the high cost of consumables in sapphire chemical mechanical polishing (CMP). In case of the pressure approach, increased pressure owing to higher deviation of pressure over the wafer leads to significant degradation of the TTV. In this study, the authors focused on reducing TTV under the high-pressure conditions. When the production equipment polishes multiple wafers attached on a carrier, higher loads seem to be concentrated around the leading edge of the head; this occurs because of frictional force generated by the combination of table rotation and the height of the gimbal of the polishing head. We believe the skewed pressure distribution during polishing to be the main reason of within-wafer non-uniformity (WIWNU). The insertion of a hub ring between the polishing head and substrate carrier helped reduce the pressure deviation. Adjusting the location of the hub ring enables tuning of the pressure distribution. The results indicated that the position of the hub ring strongly affected the removal profile, which confirmed that the position of the hub ring changes the pressure distribution. Furthermore, we analyzed the deformation of the head via finite element method (FEM) to verify the pressure non-uniformity over the contact area Based on experiment and FEM results, we determined the optimal position of hub ring for achieving uniform polishing of the substrate.

Diagnostic Imaging of Nasal Lymphoma in a Cat (고양이에서 비강 림프종의 영상 진단 증례)

  • Jung, Joo-Hyun;Seo, Kyoung-Won;Chang, Jin-Hwa;Bae, Il-Hong;Kim, Dae-Yong;Yoon, Hwa-Young;Yoon, Jung-Hee;Choi, Min-Cheol
    • Journal of Veterinary Clinics
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    • v.23 no.3
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    • pp.361-365
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    • 2006
  • A spayed female, 5-year-old, weighing 2.7 kg, domestic short hair cat was referred to Veterinary Medical Teaching Hospital, Seoul National University. The clinical signs of this patient were weight loss, sneezing, respiratory distress, nasal discharge, epistaxis, ocular discharge, left exophthalmos, and left facial edema and deformity. The laboratory tests represented mild leukocytosis. On the skull radiographs, soft tissue density filled nasal cavity with loss of turbinate detail was found. Destructive and lytic changes of the left nasal bone with soft tissue swelling were identified. On the thorax radiographs, there were a tracheobronchial lymph node swelling and a soft tissue round mass in the left caudal lung field. On computed tomographic scan images, asymmetrical destruction of turbinate and nasal septum and increased soft tissue opacity in the nasal cavity were identified. Destruction of the lateral maxillary bone, invasion to the left retrobulbar region, and craniodorsal deviation of the left eye were seen. Also, there was lysis of hard palate and cribriform plate. Invasion to the brain was found. The patient was diagnosed as nasal lymphoma by cytology and histopathology.

Changes in lipid and carnitine concentrations following repeated fasting-refeeding in mice

  • Kang, Se-Wha;Ahn, Eun-Mi;Cha, Youn-Soo
    • Nutrition Research and Practice
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    • v.4 no.6
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    • pp.477-485
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    • 2010
  • The purpose of this study was to evaluate the effects of repeated fasting and refeeding on lipid metabolism. Thirty male ICR mice, aged 6 weeks, were fed an AIN-93 control diet during the experimental period. The mice were divided into 5 groups: Non fasting group (ad libitum-fed, NF), fasting for 3 days (F), fasting for 3 days and then refeeding for 4 days repeated once (FRF1), fasting for 3 days and then refeeding for 4 days repeated twice (FRF2), and fasting for 3 days and then refeeding for 4 days repeated three times (FRF3). Rates of body weight gain, epididymal fat weight, and serum TG were significantly decreased in the F, FRF1, FRF2, and FRF3 groups, compared to the NF group. LDL-cholesterol was significantly higher in the FRF3 group than the NF and F groups, but HDL-cholesterol and HDL/TC were significantly lower in the FRF3 group than in the NF and F groups. Serum total carnitine was significantly lower in the FRF1, FRF2, FRF3 groups than the NF and F groups. However, rates of serum and hepatic acyl-carnitine concentration were significantly lower in FRF1, FRF2, and FRF3 than in NF and F. Repeated tasting-refeeding resulted in visible reductions of body weight and fat mass, but it caused ill-effects with lipid and carnitine metabolism in the body.

Correlation of Releases of Nutrient Salts in Sediment with Vicinal Oxic Conditions (퇴적물의 영양염류 용출과 호기적 조건과의 상관성 분석)

  • Cho, Dae-Chul;Lee, Eun-Mi;Park, Byung-Gi;Kwon, Sung-Hyun
    • Journal of Environmental Science International
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    • v.20 no.7
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    • pp.845-855
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    • 2011
  • The aim of this paper is to correlate the release characteristics of marine and lake sediment with their vicinal oxic conditions. We performed lab-scale simulation experiments using field sediment and water in order to compare the release concentrations and the release rates one another. To provide a few different kinds of oxic environments we used natural air flow and some oxygen releasing compounds such as $CaO_2$ and $MgO_2$. In case of phosphates, in each oxic condition, removal of phosphorus via biological activity and that via salt precipitation with the metal ions lowered the release rates. The behavior of the nitrogen-origin salts seemed to greatly depend on the typical biological actions - growth of biomass, nitrification, and partial denitrification. Generally speaking, the control of releases of $NH_3$-N, $PO_4$-P, T-N and T-P was successful under the oxic conditions meanwhile COD, nitrates and nitrites were difficult to reduce the releases into the bulk water because of the considerable microbial oxidation. Based on typical diffusive mass transfer kinetics the changes of concentrations of the nutrients were computed for qualitative and quantitative comparisons.

A Study on Visual Merchandising Perceptional Factors of Women's Fashion Brand in Department Stores (백화점 여성 의류브랜드의 비주얼 머천다이징 지각요인에 관한 연구)

  • Kim, Hung-Kyu;Lee, Ji-Soo
    • Journal of the Korean Society of Clothing and Textiles
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    • v.34 no.1
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    • pp.27-39
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    • 2010
  • In addition, an intense competition depending on the diversity of consumer demands women's clothing brands show changes in market organization such as diversification of the circulation market and general market depression in this rapidly changing fashion environment. Companies tend to use fashion VMD (a marketing-strategic approach) as a differentiation method to create a fashion brand shop image as brand differentiation becomes difficult due to generalization of techniques. This study analyzes forms and types of VMD recognized by consumers within this marketing communication environment and Q methodology was adapted to analyze the subjective internal order of individuals. First, a set of stimuli that presented the brand name and another without it were prepared (two sets in total) to examine the effects in the presentation of the brand name. Stimulants with the brand name were presented to the subjects by the same method after an experiment through stimuli without the brand name presented. As a result, VMD recognition factors were classified into 4 Q factors in cases of stimuli without brand names and 2 factors in cases of stimuli with brand names. This indicates that among brand functions, the role of simplifying information management and grasping the thoughts of consumers was applied. This study has a practical value of presenting VMD directions of each brand image based on the factors discovered.

A Study on Energy Expenditure in Korean Adolescent Women (한국 청소년 여성의 에너지 소비량에 관한 연구)

  • 김유섭;오승호
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.4
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    • pp.367-373
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    • 1993
  • A 4-week energy balance study was conducted to estimate the energy expenditure (EE) of 7 high school age girl, 15 to 16 year age, by measurement of energy intakes and changes in body energy (BE) content (intake/balance technique), keeping their normal living pattern and eating behavior. Gross energy intake (GE) and fecal energy (FE) loss was measured by bomb calorimetry. Urinary energy (UE) loss was calculated from nitrogen excreted. Fat mass (FM) was determined from body density estimated from skinfold thickness. Mean constitutional ratio of carbohydrate, protein and fat for the total energy intake was 70.1$\pm$1.8%, 12.2$\pm$0.7% and 17.7$\pm$2.0%, respectively, Fecal energy loss was 2.8% proportion of the gross energy intake. Mean daily metabolizable energy estimated by subtract fecal and urinary energy loss was 2022 $\pm$ 50㎉. Total body energy change estimated from body composition change over 28days was increased 2400 $\pm$ 950㎉ . Mean daily energy expenditure was 1958$\pm$87㎉ (39$\pm$2㎉ /kg of body weight).

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