• Journal of the Korean Geotechnical Society
• /
• v.33 no.10
• /
• pp.25-31
• /
• 2017

The buffer is one of the major components of an engineered barrier system (EBS) for the disposal of high-level radioactive waste (HLW). As the buffer is located between a disposal canister and host rock, it is indispensable to assure the disposal safety of high-level radioactive waste. It can restrain the release of radionuclide and protect the canister from the inflow of groundwater. Since high quantity of heat from a disposal canister is released to the surrounding buffer, thermal properties of the buffer are very important parameters for the analysis of the entire disposal safety. Especially, temperature criteria of the compacted bentonite buffer can affect the design of HLW repository facility. Therefore, this paper investigated thermal properties for the Kyungju compacted bentonite buffer which is the only bentonite produced in South Korea. Hot wire method and dual probe method were used to measure thermal conductivity and specific heat capacity of the compacted bentonite buffer according to the temperature variation. Thermal conductivity and specific heat capacity were decreased dramatically when temperature variation was between $22^{\circ}C{\sim}110^{\circ}C$ as degree of saturation decreased according to the temperature variation. However, there was little variation under the high temperature condition at $110^{\circ}C{\sim}150^{\circ}C$.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.32 no.2
• /
• pp.244-250
• /
• 2005

Self-injurious behavior is defined as deliberated harm to one's own body without suicidal intent. It usually occurs as head banging or hitting, body hitting, skin cutting, or finger biting and includes ocular, genital, and self-inflicted oral mutilation. Self-injurious behavior can occur with mental retardation, coma, psychotic problem, poisoning, or character disorders. In pediatric patients, self-injurious behavior usually is reported to lip, cheek and tongue biting, and many kinds of dental management methods have been introduced to prevent self-injurious behavior patients from self biting. This report presents two self-inflicted oral mutilation patients who were all treated successfully with appliances such as modified activator without wire for retention, modified tongue-rake appliance and mouth guard.

• Journal of Radiation Protection and Research
• /
• v.36 no.4
• /
• pp.200-208
• /
• 2011

The neutron fluence measurement and evaluation technology is very important for material irradiation test. The most essential technology in this study is the neutron irradiation evaluation method using a fluence monitor. The fluence monitors were fabricated with metal wires of the purity ${\geq}$ 99.9%, whose dimensions were 0.1mm diameter, about 3 mm length, and around 150-200 ${\mu}g$ mass range. Three wire samples (Fe, Ni, Ti) were prepared for one irradiation aluminum capsule. Five capsules were irradiated in the OR5 hole of the HANARO reactor at 30 MW power for about 25 days. After irradiation tests, radiation activities were measured with the high purity germanium (HPGe) detector. The reaction rates were calculated by using the measured radiation activity data, and then neutron fluence were obtained from the reaction rates and the weighted neutron cross section with calculated neutron spectrum at the fluence monitor position.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.6
• /
• pp.1-10
• /
• 2011

In designing multi-core processors, interconnection delay is one of the major constraints in performance improvement. To solve this problem, the 3-dimensional integration technology has been adopted in designing multi-core processors. The 3D multi-core architecture can reduce the physical wire length by stacking cores vertically, leading to reduced interconnection delay and reduced power consumption. However, the power density of 3D multi-core architecture is increased significantly compared to the traditional 2D multi-core architecture, resulting in the increased temperature of the processor. In this paper, the floorplan methods which change the forms of vertical placement of the core and the level-2 cache are analyzed to solve the thermal problems in 3D multi-core processors. According to the experimental results, it is an effective way to reduce the temperature in the processor that the core and the level-2 cache are stacked adjacently. Compared to the floorplan where cores are stacked adjacently to each other, the floorplan where the core is stacked adjacently to the level-2 cache can reduce the temperature by 22% in the case of 4-layers, and by 13% in the case of 2-layers.

• The korean journal of orthodontics
• /
• v.20 no.3 s.32
• /
• pp.447-462
• /
• 1990

The objective of this experiment is to observe structural differences in the othodontic movement of vital (control group) and devitalized (experimental group) teeth in the mongrel dogs. The 5 utilized dogs in this experiment were approximately 1 year of age and their average weight was about 12 Kg. Endodontic therapy was performed on the 2nd premolars in upper & lower jaws of each animal under the general anesthesia by intravascular injection of 25mg/kg of pentobarbital sodium. The canals of the teeth were obturated by using gutta percha in conjunction with root canal sealer (AH26 Densply). One of the roots in the 2nd premolars was hemisected to make an extraction space for the devitalized teeth to be moved. The edgewise technique was employed for the movement of the teeth. Orthodontic models and intraoral roentgenograms were taken before and after orthodontic tooth movement. The open coil springs (.010 x .040) were used at interbraket space in order to provide equal forces (75gm) between the teeth in each arch wire. After 13 weeks of active orthodontic tooth movement, dogs were sacrified and the experimental results w ere examined through the intraoral radiography, microscopic examination and scanning electromicroscopic examination at the root sulfate. From the results of the study, the following conclusions may be drawn: The root resolution and cemental deposition were observed within the pressure and tension site in both group. 2. The root resorbed lacunae were observed in the cementum and/or into the dentin in both group. 3. The prominent osteoblastic activities were observed on the alveolar margin in the tension site in both group. 4. A few of blood vessels were observed in the pressure site, but also lots of blood vessels were observed in the tension site especially in the periphery of the alveolar bone in both group. 5. In the pressure site, resorbed lacunae were formed with deep and narrow cavity in the control group; the shallow and wide cavity in the experimental group. 6. In the pressure site, the repaired cementum or cementoid tissue was lined on cementum in the experimental group, but not in the control group. 7. There was no significant difference between external root resolution of endodontically and vital teeth when both were subjected to orthodontic forces.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.2 no.4
• /
• pp.204-208
• /
• 2000

Little information is available for the temporal variation in air temperature profile within rice canopies under development, while much works have been done for a fully developed canopy. Fine wire thermocouples of 0.003 mm diameter (chromel-constantan) were installed at 10 vertical heights by a 10 cm step in a paddy rice field to monitor the air temperatures over and within the developing rice canopy from one month after transplanting (June 29) to just before heading (August 24). According to a preliminary analysis of the data, we found neither the daytime temperature maximum nor the night time minimum at the active radiation surface (the canopy height with maximum leafages) during this period, which is a typical profile of a fully developed canopy. Air temperature within the canopy never exceeded that above the canopy at 1.5 m height during the daytime. Temporal march of the within-canopy profile seemed to be controlled mainly by the ambient temperature above the canopy and the water temperature beneath the canopy, and to some extent by the solar altitude, resulting in alternating isothermal and inversion structures.

• Restorative Dentistry and Endodontics
• /
• v.17 no.1
• /
• pp.22-35
• /
• 1992

The aim of this study was to investigate the effect of herbal organic extracts on the pain response provoked by noxious stimuli on dental nerve and the peripheral nerve conduction. Cats (2-2.5Kg regardless of sex) that were chosen as experimental animals were classified into control group, Asiasari radix application group and Zingiberis rhizoma application group. They were anesthetized with ${\alpha}$-chloralose, then anterior belly of digastric muscle of both sides were exposed and wire electrodes were inserted for recording of Electromyogram (EMG). Cavities were prepared on canines until pulp of the teeth were exposed. And after the drugs solubilized for 2% and 4% concentration (W/V) in vehicle were applied, their effects were compared through the recording of EMG immediately after drug application, 30 minutes, 60 minutes, 120 minutes and 5 days after, respectively. And after both inferior alveolar nerves were exposed, 4% organic extracts of Zingiberis rhizoma and Asiasari radix were applied for 30 minutes then the change of jaw opening reflex provoked by noxious stimuli on pulpal nerves were observed immediately after washing out, at 30, 60 and 90 minutes after drug had been washed out. After saphenous nerve of both sides were exposed, one side of nerve was used for vehicle application and the other side was used for drug application for 30 minutes. Then conduction of action potential of A-${\delta}$ and C-fiders of saphenous nerves, which have changed with time, was recorded. With analysis of these records, the following results were obtained: 1. Organic extract of Zingiberis rhizoma (2% or 4% concentration) greatly suppressed EMG of digastric muscle provoked by noxious stimuli on pulpal nerve at five days after application, the suppressive: effect was greater than that of organic extract of Asiasari radix. 2. Organic extract of Asiasari radix (2% or 4% concentration) suppressed jaw opening reflex provoked by noxious stimuli on pulpal nerve, at 5 days after drug application. 3. Organic extract of Zingiberis rhizoma and Asiasari radix (immediately after 30 minutes application) suppressed neural conduction of A-${\delta}$ and C-fibers, the suppressive effect was greater on A-${\delta}$ fibers than on C-fibers. 4. Jaw opening reflex provoked by noxious stimuli on pulpal nerve in inferior alveolar nerve was greatly suppressed 30 minutes after drug application, this effect was greater by Zingiberis rhizoma than by Asiasari radix.

• Journal of the Korean Wood Science and Technology
• /
• v.36 no.3
• /
• pp.70-84
• /
• 2008

A series of the studies on the applied physical properties of domestic species have been conducted last three years. Pinus densiflora was one of the three species examined for the first year. Because the same apparatus and experimental procedures were used for all species, their results can be easily comparable. The experiments for sorption property were conducted with 20- and 80-mesh wood powder and resulted in their EMC's and sorption isotherms at various heating conditions. The thermal conductivity and diffusivity, and electric resistance and volumetric electric resistivity were measured with a thermal-wire device and a high electric resistance meter. The differences of the thermal and electric properties between quarter- and flat-sawn specimens were observed, which was partially attributed to their anatomical differences. An acoustic measurement system was used to evaluate dynamic MOE and internal friction. This paper provides the useful fundamental data for designing a wood structure, correcting a portable resistance-type moisture meter, and nondestructive testing wood.

• Journal of Animal Environmental Science
• /
• v.18 no.2
• /
• pp.91-94
• /
• 2012

This study was conducted to develop an algorithm for determination of abnormal body temperature in piglets through skin and core temperature database at normal condition. 5 piglets (mean BW : 46 kg) were employed for the experiment. They were adapted in the individual metabolism cage set at $22.5{\pm}2.0^{\circ}C$ of room temperature for 2 weeks before the measurement of body temperature. Ear, neck, head and subcutaneous neck temperature (as core temperature) of piglets were measured for every 1 minute during 30 consecutive days through 1mm k-type thermocouple wire and NI-devices (National Instruments Corporation, Austin, Texas, USA). Body temperature data were accumulated and integrated into the 1 day unit. Change of daily mean skin and core body temperatures in piglets were lowest at around 06:00, highest at around 14:00 and gradually decreased until the day after 06:00. Each skin temperatures were varied with the measuring site and largely depended on the room temperature changes. Established database of skin and core body temperature in piglets through this study can be applied to develop an algorithm for monitoring and determining the abnormal condition of animal by using radio frequency identification.

• The KIPS Transactions:PartD
• /
• v.16D no.1
• /
• pp.133-138
• /
• 2009

This paper introduces a pilot CDMA network-based wireless lap time measurement system set up on a ski slope of Yongpyong Ski Resort. The wireless lap time measurement system is one output of U-Sports Project of Gangwon Province, which is intendended for promoting local strategic business and preparation for hosting 2018 Winter Olympic Games at Pyeongchang. A pair of laser sensors is installed at the entry and exit points of a section requiring lap time measurement on a ski slope. Each laser sensor is connected to a sensor node via wire so that the sensor node can detect the time when a skier enters or exits the section. Also each sensor node is connected to a CDMA network via a modem and receives a standard time from a NTP server. Each node executes the NTP algorithm to synchronize its local time to the received server time. As a result of the time synchronization, the sensor nodes maintain its local time within a resolution of at least 10 miliseconds and transmit the time of detection to a central control center. While the wireless lap time measurement system introduced in the paper does not need expensive measurement equipment, the system allows the central control center to provide lap time records in a more convenient manner compared to conventional manual lap time measuremnt methods.