• Journal of Korean Tunnelling and Underground Space Association
• /
• v.13 no.4
• /
• pp.319-345
• /
• 2011

In case of tunnels in cold regions, a freeze of groundwater around tunnel may act as a barrier of tunnel drainage in winter, or may cause the inner extrusion of lining. In spite of that, a design of insulation for preventing the frost damage of tunnel lining has not been introduced in Korea, while foreign countries such as Norway and so on have a standard on insulation. In this study, a few freezing cases of road tunnels have been reviewed, and the results show that the freezing protection is necessary. In order to characterize the thermal distribution in the tunnel, following measurements have been performed at Hwa-ak tunnel; the temperature distribution by longitudinal lengths, the internal temperature of lining and the temperature distribution of the ground under pavement. From these measurements, the characteristics of the tunnel's internal temperature distribution due to temperature change in the air has been analyzed. Based on the measurement results on the temperature distribution at Hwa-ak tunnel, thermal flow tests on the rock specimen with and without insulation have been performed in the artificial climate chamber to investigate the performance of the insulation. Also, a number of 3D numerical analyses have been performed to propose appropriate insulation and insulation thicknesses for different conditions, which could prevent the frost damage of tunnel lining. As a result of the numerical analysis, air freezing index of 291$^{\circ}C{\cdot}$ Hr has been suggested as the threshold value for freezing criteria of groundwater behind the tunnel lining.

• Journal of Bio-Environment Control
• /
• v.22 no.1
• /
• pp.35-41
• /
• 2013

This study was conducted to provide data necessary for reducing the condensation on greenhouse covering in winter season. The variation of VPD (Vapor Pressure Deficit) and condensation flux was analyzed in experimental tomato greenhouse. VPD values in experimental plastic greenhouse were greater than 0.2 kPa of disease prevention threshold, and lower than 0.5 kPa of threshold for dehumidification. The surface temperature of inside covering was slightly higher than the average temperature of outside and above curtain, and changed according to outside temperature. The humidity above curtain was nearly 100% and good condition for condensation. The humidity below curtain was 75~90% and comparatively stable condition for growing. The condensation flux value in experimental greenhouse corresponded with result of Seginer and Kantz (1986).

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.2
• /
• pp.235-242
• /
• 2017

A driving controller for active destruction protections can be applied to machinery, aerospace and military fields. In particular, this controller can be used to track and attack enemy flying objects through the active control. It is important to ensure reliability of the driving controller since its operation should be kept with precision to the target point. The temperature of the environment where the driving controller is used is about -32 C ~ 50 C (241~323 ). Heat generated in the driving controller should be maintained below a certain threshold (85 C (358 )) to ensure reliability; therefore, the study and analysis of the heat flow characteristics in the driving controller are required. In this research, commercial software Solid-Works Flow Simulation was used for the numerical simulation assuming a low Reynolds number turbulence model and an incompressible viscous flow. The goal of this paper is to design the driving controller safely by analyzing the characteristics of the heat flow inside of the controller composed of chips or boards. Our analysis shows temperature distributions for boards and chips below a certain threshold.

• Korean journal of applied entomology
• /
• v.61 no.4
• /
• pp.563-575
• /
• 2022

Maruca vitrata is one of important pests in leguminous crops, especially red bean. We investigated the effects of temperature on development of each life stage, adult longevity and fecundity of M. vitrata for understanding the biological characteristics of the insect species at eight constant temperatures of 13, 16, 19, 22, 25, 28, 31, and 34℃. Eggs hatched successfully at all temperature subjected and larvae successfully developed to the adult stage from 16℃ to 31℃. The developmental period of egg decreased up to 31℃ and after then increased. The developmental period of larva and pupa, and adult longevity of M. vitrata decreased with increasing temperature. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. vitrata were estimated by linear regression as 12.8℃ and 280.8DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 14.2℃ and 31.9℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. vitrata was 17.7℃. In addition, we constructed the oviposition models of adult, using the investigated adult traits including survival, longevity, oviposition period and fecundity. Temperature-dependent development models and adult oviposition models will be helpful to understand the population dynamics of M vitrata and to establish the strategy of integrated pest management in legume crops.

• Korean journal of applied entomology
• /
• v.61 no.4
• /
• pp.577-590
• /
• 2022

Ostrinia scapulalis is one of important pests in leguminous crops, especially red bean. In order to understand the biological characteristics of the insect, we investigated the effects of temperature on development of each life stage, adult longevity and fecundity of O. scapulalis at eleven constant temperatures of 7, 10, 13, 16, 19, 22, 25, 28, 31, 34, and 36℃. Eggs and larvae successfully developed next life stage at most temperature subjected except 7, 10 and 13℃. The developmental period of egg, larva and pupa decreased as temperature increased. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of O. scapulalis were estimated by linear regression as 13.5℃ and 384.5DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 19.4℃ and 39.8℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of O. scapulalis was 20.4℃. Adults produced viable eggs at the temperature range between 16℃ and 34℃, and showed a maximum number, ca. 416 offsprings, at 25℃. Adult models including aging rate, age-specific survival rate, age-specific cumulative oviposition, and temperature-dependent fecundity were constructed, using the temperature-dependent adult traits. Temperature-dependent development models and adult oviposition models will be useful components to understand the population dynamics of O. scapulalis and will be expected using a basic data for establishing the strategy of integrated pest management in leguminous crops.

• Korean journal of applied entomology
• /
• v.61 no.3
• /
• pp.435-447
• /
• 2022

The soybean podborer, Matsumuraeses falcana (Lepidoptera: Tortricidae), is one of important pests in soybean crop. In the purpose of forecasting population dynamics of M. falcana, we investigated the effects of temperature on development of each life stage, adult longevity and fecundity of Matsumuraeses falcana at seven constant temperatures of 10, 13, 19, 22, 25, 28, and 31℃. Eggs hatched successfully at all temperature subjected. M. falcana developed from egg hatching to adult emergence at the tested temperatures except 10, 13, and 31℃. The developmental period of each life stage and adult longevity of M. falcana decreased as temperature increased. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. falcana were estimated by linear regression as 10.2℃ and 492.04DD, respectively. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. TL and TH from egg hatching to adult emergence using SSI model were 16.7℃ and 29.1℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. falcana was 12.4℃. We constructed the adult oviposition model of M. falcana using adult survivorship and fecundity. Temperature-dependent immature development and adult oviposition models will help constructing the population model of M. falcana and developing the strategies of integrated pest management in soybean fields.

• Korean journal of applied entomology
• /
• v.61 no.3
• /
• pp.461-473
• /
• 2022

Matsumuraeses phaseoli is one of important pests in soybean crops, especially adzuki beans. We investigated the effects of temperature on development of each life stage, adult longevity and fecundity of M. phaseoli for understanding the biological characteristics of M. phaseoli at ten constant temperatures of 7, 10, 13, 16, 19, 22, 25, 28, 31, and 34℃. Eggs hatched successfully at all temperature subjected except 7℃ and 34℃. The developmental period of each life stage and adult longevity of M. phaseoli decreased as temperature increased. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. phaseoli were estimated by linear regression as 9.04℃ and 422.97DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 20.0℃ and 32.3℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. phaseoli was 12.3℃. We constructed the adult oviposition model of M. phaseoli using adult survivorship and fecundity. Temperature-dependent development models and adult oviposition models will be helpful to understand the population dynamics of M. falcana and to establish the strategy of integrated pest management in soybean fields.

• Korean Journal of Materials Research
• /
• v.1 no.3
• /
• pp.132-138
• /
• 1991

A comparision was made on the influence of BPSG flow temperatures on the electrical properties in submicron CMOS DRAMs containing two BPSG layers. Three different combinations of BPSG flow temperature such as $850^{\circ}C/850^{\circ}C,\;850^{\circ}C/900^{\circ}C,\;and\;900^{\circ}C/900^{\circ}C$ were employed and analyzed in terms of threshold, breakdown and isolation voltage along with sheet resistance and contact resistance. In case of $900^{\circ}C/900^{\circ}C$ flow, the threshold voltage of NMOS was decreased rapidly in channel length less than $0.8\mu\textrm{m}$ with no noticeable change in PMOS and a drastic decrease in breakdown voltages of NMOS and PMOS was observed in channel length less than and equal to $0.7\mu\textrm{m}$ and $0.8\mu\textrm{m}$, respectively. Little changes in threshold and breakdown voltages of NMOS and PMOS, however, were shown down to channel length of $0.6\mu\textrm{m}$ in case of $850^{\circ}C/850^{\circ}C$ flow. The isolation voltage was increased with decreasing BPSG flow temperature. A significant increase in the sheet resistance and contact resistance was noticeable with decreasing BPSG flow temperature from $900^{\circ}C$ to $850^{\circ}C$. All these observations were rationalized in terms of dopant diffusion and activation upon BPSG flow temperature. Some suggestions for improving contact resistance were made.

• Journal of Korean Medicine Rehabilitation
• /
• v.19 no.3
• /
• pp.15-32
• /
• 2009

Objectives : The purpose of this Study was to identify the effect of Dokhwalgisaeng-tang(Duhuoqisheng-tang) and Jungsongouhyul pharmacopuncture on pain control and nerve regeneration after crush injury in rat sciatic nerve. Methods : Neuropathic pain was induced by crush-induced model of right sciatic nerve. Animal groups were divided as follows; Group I: no treatment control group, Group II : experimental group treated with Dokhwalgisaeng-tang(Duhuoqisheng-tang), Group III : experimental group treated with Jungsongouhyul pharmacopuncture, and Group IV : experimental group treated with Dokhwalgisaeng-tang(Duhuoqisheng-tang) and Jungsongouhyul pharmacopuncture. To evaluate pain intensity, each group was observed paw withdrawal threshold and immunoreactivity on the c-fos before and after respective treatments in five hours, first, third, and fifth day. To evaluate nerve regeneration, those were observed SFI(Sciatic Functional Index) and GAP-43(Growth Associated Protein 43) after each treatment in seventh and thirteenth day. Results : 1. Paw withdrawal threshold to the mechanical stimuli made the significant difference between group IV and the control group after five days of the experiment. 2. Paw withdrawal threshold to the thermal stimuli made the significant difference between group I and III, I and IV, II and IV. 3. In immunohistochemical response of c-fos, as time passes, the immunoreactivity of all groups was decreased gradually. Especially, group IV was observed the lowest after three days. 4. The differences of sciatic function indexes in each group were significantly between group I and III, I and IV, II and IV after 14 days, and between group I and III, I and IV, II and IV, III and IV after 21 days. 5. In immunohistochemical response of GAP-43, all groups had higher GAP-43 immunoreactivity at the 14 days from post-injury and group IV showed highest immunoreactivity. Conclusions : Based on above the results, it is proposed that Dokhwalgisaeng-tang(Duhuoqisheng-tang) and Jungsongouhyul pharmacopuncture may be helpful as a treatment in neuropathic pain and nerve regeneration in rat model.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2014.02a
• /
• pp.347.2-347.2
• /
• 2014

최근, 비정질 산화물 반도체 thin film transistor (TFT)는 수소화된 비정질 실리콘 TFT와 비교하여 높은 이동도와 큰 on/off 전류비, 낮은 구동 전압을 가짐으로써 빠른 속도가 요구되는 차세대 투명 디스플레이의 TFT로 많은 연구가 진행되고 있다. 한편, 기존의 Thin-Film-Transistor 제작 시 우수한 박막을 얻기 위해서는 $500^{\circ}C$ 이상의 높은 열처리 온도가 필수적이며 이는 유리 기판과 플라스틱 기판에 적용하는 것이 적합하지 않고 높은 온도에서 수 시간 동안 열처리를 수행해야 하므로 공정 시간 및 비용이 증가하게 된다는 단점이 있다. 이러한 점을 극복하기 위해 본 연구에서는 간단하고, 낮은 제조비용과 대면적의 박막 증착이 가능한 용액공정을 통하여 박막 트랜지스터를 제작하였으며 thermal 열처리와 microwave 열처리 방식에 따른 전기적 특성을 비교 및 분석하고 각 열처리 방식의 열처리 온도 및 조건을 최적화하였다. P-type bulk silicon 위에 산화막이 100 nm 형성된 기판에 spin coater을 이용하여 Al-Zn-Sn-O 박막을 형성하였다. 그리고, baking 과정으로 $180^{\circ}C$의 온도에서 10분 동안의 열처리를 실시하였다. 연속해서 Photolithography 공정과 BOE (30:1) 습식 식각 과정을 이용해 활성화 영역을 형성하여 소자를 제작하였다. 제작 된 소자는 Junctionless TFT 구조이며, 프로브 탐침을 증착 된 채널층 표면에 직접 접촉시켜 소스와 드레인 역할을 대체하여 동작시킬 수 있어 전기적 특성을 간단하고 간략화 된 공정과정으로 분석할 수 있는 장점이 있다. 열처리 조건으로는 thermal 열처리의 경우, furnace를 이용하여 $500^{\circ}C$에서 30분 동안 N2 가스 분위기에서 열처리를 실시하였고, microwave 열처리는 microwave 장비를 이용하여 각각 400 W, 600 W, 800 W, 1000 W로 15분 동안 실시하였다. 그 결과, furnace를 이용하여 열처리한 소자와 비교하여 microwave를 통해 열처리한 소자에서 subthreshold swing (SS), threshold voltage (Vth), mobility 등이 비슷한 특성을 내는 것을 확인하였다. 따라서, microwave 열처리 공정은 향후 저온 공정을 요구하는 MOSFET 제작 시의 훌륭한 대안으로 사용 될 것으로 기대된다.