• Title/Summary/Keyword: pitfall

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Classification of Organs Using Impedance of Ultrasonic Surgical Knife to improve Surgical Efficiency (초음파 수술기의 수술 효율성 향상을 위한 진동자 임피던스 측정에 따른 조직 분류 연구)

  • Kim, Hong Rae;Kim, Sung Chun;Kim, Kwang Gi;Kim, Young-Woo
    • Journal of Biomedical Engineering Research
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    • v.34 no.3
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    • pp.141-147
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    • 2013
  • Ultrasonic shears is currently in wide use as an energy device for minimal invasive surgery. There is an advantage of minimizing the carbonization behavior of the tissue due to the vibrational energy transfer system of the transducer by applying a piezoelectric ceramic. However, the vibrational energy transfer system has a pitfall in energy consumption. When the movement of the forceps is interrupted by the tissue, the horn which transfers the vibrational energy of the transducer will be affected. A study was performed to recognize different tissues by measuring the impedance of the transducer of the ultrasonic shears in order to find the factor of energy consumption according to the tissue. In the first stage of the study, the voltage and current of the transducer connecting portion were measured, along with the phase changes. Subsequently, in the second stage, the impedance of the transducer was directly measured. In the final stage, using the handpiece, we grasped the tissue and observed the impedance differences appeared in the transducer To verify the proposed tissue distinguishing method, we used the handpiece to apply a force between 5N and 10N to pork while increasing the value of the impedance of the transducer from 400 ${\Omega}$.. It was found that fat and skin tissue, tendon, liver and protein all have different impedance values of 420 ${\Omega}$, 490 ${\Omega}$, 530 ${\Omega}$, and 580 ${\Omega}$, respectively. Thus, the impedance value can be used to distinguish the type of tissues grasped by the forceps. In the future study, this relationship will be used to improve the energy efficiency of ultrasonic shears.

Diversity and Abundance of Ground-beetles (Coleoptera) in Mt. Gabjangsan, Korea (보행성 딱정벌레류의 다양성 및 풍부도에 관한 연구 -경북 상주시 갑장산-)

  • Park Jong Kyun;Yeon Hwa Soon;Trac Dam Huu
    • The Korean Journal of Soil Zoology
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    • v.8 no.1_2
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    • pp.32-36
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    • 2003
  • Diversity and altitudinal distribution of the ground-beetles including Silphidae were investigated on Mt. Gabjangsan, Sangju city, Korea. Of the collected 10 species belonging to 3 families, Synuchus cycloderus was the most abundant species and S. nitidus was the relatively more abundant than the other species. The highest number collected was at alto 700 m. Simpson dominance index was 0.66 the highest at 700 malt., whereas, 0.47 at alto 800 m, was the lowest. The highest Simpson diversity index was noticed at alto 800 m (0.53). Also, seasonal indices of diversity and dominance of Simpson and Menhinick index were provided.

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Differences in Temporal Variation of Ground Beetle Assemblages (Coleoptera: Carabidae) between Two Well-Preserved Areas in Mt. Sobaeksan National Park

  • Jung, Jong-Kook;Suk, Sang-Wook;Kim, Byeong-Young;Hong, EuiJeong;Kim, Youngjin;Jeong, Jong-Chul
    • Journal of Forest and Environmental Science
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    • v.33 no.2
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    • pp.122-129
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    • 2017
  • Understanding how future climate conditions will be impact on the biodiversity and species composition is important, because biodiversity becomes more important in environment assessment. To understand the biological changes including diversity and species composition over time (temporal variation within a year), the species diversity and composition of ground beetles were investigated in two well-preserved areas in the Sobaeksan National Park using pitfall traps. In addition, relationships between ground beetles and environmental variables were studied by considering temporal variation. We collected 2,146 ground beetle specimens representing 45 species, and individual-based rarefaction curves indicated that similar species richness was found between Geumseon Valley (GV) and Namcheon Valley (NV). The Bray-Curtis matrix comparisons between study sites were characterized by similar ground beetles sample heterogeneity, while temporal variations in abundance, species richness, and ${\beta}-diversity$ of ground beetles showed rather difference over time according to location of study sites. In GV site, minimum temperature was selected as the best predictor for abundance, species richness, and ${\beta}-diversity$ of ground beetles, while those relationships in NV site were more complicated. In conclusion, our study suggests that understanding the different response of ground beetles to climatic variables related to local habitat conditions is important to predict the effect of climate change on biological communities.

Kinetic Analyses on Thermal Degradation of Epoxy Based Adhesive for Packaging Application (센서 패키지용 고분자 접착제의 열화 거동 분석)

  • Kim, Yeong K.;Lee, Yoon-Sun
    • Journal of the Microelectronics and Packaging Society
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    • v.24 no.1
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    • pp.67-73
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    • 2017
  • An analysis of thermal degradation of epoxy based adhesive performed by thermogravimetry tests are presented in this study. Six different heating rates were employed for the weight change measurements. Based on the data, an Arrhenius type modeling equation was developed by calculating activation energies and proportional constants, and $n^{th}$ polynomial function was adopted to predict the weight change rates. The prediction results by the modeling was compared with the data using the average activation energy. It was found that the activation energy at the each heating rate was not same due to the different degradation kinetics, especially at the high heating rate. To overcome this pitfall, a new approach using exponential function series was introduced and employed. The calculation results showed very good agreements with the test data regardless of the heating rates.

Spade-Shaped Anastomosis Following a Proximal Gastrectomy Using a Double Suture to Fix the Posterior Esophageal Wall to the Anterior Gastric Wall (SPADE Operation): Case-Control Study of Early Outcomes

  • Han, Won Ho;Eom, Bang Wool;Yoon, Hong Man;Ryu, Junsun;Kim, Young-Woo
    • Journal of Gastric Cancer
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    • v.20 no.1
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    • pp.72-80
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    • 2020
  • Purpose: Proximal gastrectomy (PG) is a function-preserving surgery in cases of proximally located early-stage gastric cancer. Because gastroesophageal reflux is a major pitfall of this operation, we devised a modified esophagogastrostomy (EG) anastomosis to fix the distal part of the posterior esophageal wall to the proximal part of the anterior stomach wall to produce an anti-reflux mechanism; we named this the SPADE operation. This study aimed to show demonstrate the clinical outcomes of the SPADE operation and compare them to those of previous PG cases. Materials and Methods: Case details of 56 patients who underwent PG between January 2012 and March 2018 were retrospectively reviewed: 30 underwent conventional esophagogastrostomy (CEG) anastomosis using a circular stapler, while 26 underwent the SPADE operation. Early postoperative clinical outcome-related reflux symptoms, endoscopic findings, and postoperative complications were compared in this case-control study. Results: Follow-up endoscopy showed more frequent reflux esophagitis cases in the CEG group than in the SPADE group (30% vs. 15.3%, P=0.19). Similarly, bile reflux (26.7% vs. 7.7%, P=0.08) and residual food (P=0.01) cases occurred more frequently in the CEG group than in the SPADE group. In the CEG group, 13 patients (43.3%) had mild reflux symptoms, while 3 patients (10%) had severe reflux symptoms. In the SPADE group, 3 patients (11.5%) had mild reflux symptoms, while 1 had severe reflux symptoms (absolute difference, 31.8%; 95% confidence interval, 1.11-29.64; P=0.01). Conclusions: A novel modified EG, the SPADE operation, has the potential to decrease gastroesophageal reflux following a PG.

Insect Diversity on the Paddy Field Wetland, Gonggeom-ji, Sangju, first designed by Ministry of Environment, Korea (국내 최초 환경부 지정 논 습지 지역인 공검지의 곤충 다양성)

  • Kim, Myeong-Hwan;Hwang, Jeong-Ho;Choi, Eun-Young;Park, Jinyoung;Park, Jong-Kyun
    • Journal of Wetlands Research
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    • v.19 no.1
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    • pp.155-163
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    • 2017
  • This study was conducted to know the wetland insect diversity at Gonggeom-ji in Sangju city which is the first designated paddy field wetland protection by the Ministry of Environment of Korea in 2011. Data was collected at four times from March to November in 2014 using by Searching, Sweeping and Pitfall trap methods. In this study a total of 227 species of 205 genera belonging to 78 families from 8 orders were collected and individuals were 1,327. Among them, the order of Coleoptera was the most species-rich (42.73%), Hemiptera was the second order (22.47%). In the total diversity index (H') was 6.339 that means highly positive. Dominant Index (DI) was 0.143, Evenness index (EI) was 0.810. Over all survey periods, interspecies competitiveness was high, and community stability was also high. Therefore Gonggeom-ji wetland revealed stable and positive environmental situation.

Community Structure, Species Diversity of Insects (ants, ground beetles), and Forest Health in the Hongneung Forest (홍릉 숲의 곤충(개미와 지표성 딱정벌레)의 군집구조, 종다양성, 산림건강성)

  • Lee, Cheol Min;Kwon, Tae-Sung
    • Journal of Korean Society of Forest Science
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    • v.102 no.1
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    • pp.97-106
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    • 2013
  • The present study is aimed to evaluate forest health in a fragmented urban forest using characteristics of insect communities. Ants (Formicidae) and ground beetles (Carabidae) surveyed by pitfall trap method in the Hongneung forest located in the urban area of Seoul were compared with those in the Gwangneung forest. The Gwangneung forest is supposed to be health due to its high biodiversity and well-conserved nature. Ants of the Hongneung forest was much more abundant compared with those of the Gwangneung forest. However, ground beetles showed the opposite patterns; much more abundant in the Gwangneung forest than in the Hongneung forest. Species richness was higher in the Gwangneung forest than in the Hongneung forest, but species diversity was higher in the Hongneung forest. In the Hongneung forest, forest specialist species and generalist species were balanced, whereas few forest specialists dominated in the Gwangneung forest. This dominance decreased species diversity in those Gwangneung forest. Thus, characteristics of insect community in the Hongneung forest were greatly different with those in the Gwangneung forest.

Altitudinal Distribution of Ants in Mt. Gariwangsan, Korea (가리왕산 지역의 개미 고도별 분포)

  • Cho, Kyoung-Yeon;Kim, Il-Kwon;Lyu, Dong-Pyeo
    • Korean Journal of Environment and Ecology
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    • v.34 no.2
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    • pp.115-120
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    • 2020
  • This study investigated the dominant species and the population variation of the ant species, an indicator species of biodiversity, to obtain basic data on the changes of population according to the future climate change. The survey period was from June to September 2013, and we investigated the distribution of ants by square irradiation method (10m × 10m) using traps. The survey in each altitude identified a total of 14 species of 11 genera in 3 subfamilies and collected 15,466 individuals. We confirmed the distribution of 4,548 individuals of 13 species at low altitude (700m), and the dominant species was Aphaenogaster japonica (49.9%). At the middle altitude (900m), we collected 9,129 individuals of 8 species, and the dominant species was Pheidole fervida (57.7%). At high altitude (1,100m), we identified 1,789 individuals of 10 species, and Myrmica kotokui (43.3%) was the dominant species. It was confirmed that Aphaenogaster japonica, Nylanderia flavipes, and Pheidole fervida were widely distributed throughout the altitudes.

Structure and Seasonal Patterns of Ground Beetles Community in Wangpi-Cheon Watershed, South Korea

  • Park, Jinyoung;Jung, Jong Kook;Cha, Jin Yeol;Choi, Jong Bong;Park, Jong Kyun
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.1 no.1
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    • pp.41-51
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    • 2020
  • Ground beetle fauna of Wangpi-cheon watershed in Yeongyang-gun to Uljin-gun, Gyeongsangbuk-do was investigated from May to October in 2012. Ground beetles were collected by pitfall trapping. A total of 38 species of 20 genera belonging to 8 subfamilies were identified from 2,486 collected ground beetles. Species richness was high in Pterostichinae (16 species), Carabinae (8 species), Harpalinae (5 species), Callistinae (3 species), Nebriinae (3 species) and others (1 species). Dominant species were Synuchus cycloderus (1,025 individuals) and Aulonocarabus seishinensis seishinensis (332 individuals), Pristosia vigil (133 individuals), and Coptolabrus smaragdinus branickii (117 individuals) in order. Monthly changes in abundance of upper dominante genera Pterostichus, Aulonocarabus, Coptolabrus species and Synuchus, Pristosia, Colpodes species showed that the former had the highest number in August whereas the latter increased in June and September. The genus Pterostichus species were preferred in deciduous forest in Wangpi-cheon watershed, while the genus Synuchus species were collected in mixes forest adjacent to farmland and recreation facilities and the genera Chlaenius, Harpalus species were collected in mixes forest adjacent to farmland nearby stream. Non-metric multidimensional scaling (NMDS), ground beetles and sites could be divided into two distinct groups: St. 1, St. 2, St. 3 group and St. 4 group. Some species such as Pterostichus orientalis orientalis, P. vicinus and P. bellatrix were particularly abundant at St. 4.

The Change in the Outpatient Visit to Tertiary care Hospital after the Implementation of the Separation of Prescription and Drug Dispensing Policy (의약분업 전.후 3차 진료기관 외래이용 변화)

  • Cho, Dong-Yeong;Yu, Seung-Hum;Sohn, Tae-Yang
    • Korea Journal of Hospital Management
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    • v.7 no.1
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    • pp.19-40
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    • 2002
  • The purpose of this study is to find out if there has been any change in the outpatient visit to tertiary care hospitals after the introduction of the new healthcare program that divides the roles of doctors and pharmacists and the reason for the change if there is any. Two tertiary care hospitals with the largest capacity of 1200 beds and two tertiary care hospitals with the lowest capacity of 600-700 beds were randomly selected. Data of the outpatient visits from March-May 2(xx), before the new healthcare system was adopted, were compared with the data from March-May 2001, after the new policy was adopted. Outpatient visits have decreased 5.8% after the new system. There has been a dramatic decrease, especially, in the department of OB-GYN and Pediatrics of tertiary hospitals. Decrease in re-visits is much higher than the first visits. Female patients decreased more than the male patients. Outpatient visits by economically active patients group aged 25-44 declined much. Tertiary hospitals in Seoul and Kyonggi Province, as well. Outpatient income of tertiary hospitals has dropped up to 14.7% due to the decline in outpatient visits and pharmaceutical income, and resell price system which in turn has caused the hospital financial deficits. While the new program has succeeded in lowering the use of antibiotics and injections, it has the pitfall of prescribing long days and expensive drugs. A full-fledged review of the system should be conducted for the establishment of the new system and I believe this study may be a useful references. Furthermore, more profound and overall studies on the chance in the patients use of hospitals are needed.

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