• 한국태양에너지학회:학술대회논문집
• /
• 2008.04a
• /
• pp.241-246
• /
• 2008

In this paper, we analyze the I-V curve and hot-spot phenomenon caused by solar cells' serial and parallel connected circuit. The mis-match loss of parallel interconnection with low Isc string decrease lower than serially interconnected one and temperature caused by hot-spot does. Also, mis-match loss of parallel interconnection with low Voc string increase more than serially interconnected one. The string having low Voc happened hot-spot phenomenon when open circuit. The bad solar cell in string gives revere bias to good solar cell and make hot-spot phenomenon. If we consider the mis-match loss, when designing PV module and array. the efficiency of PV system might increase.

• Journal of Energy Engineering
• /
• v.1 no.1
• /
• pp.58-65
• /
• 1992

Pt loaded porous carbon Pt/C electrode was prepared by hot pressing process to enhance the electrode performance in PAFC (phosphoric acid fuel cell). By changing the hot pressing conditions and PTFE contents, Pt/C electrodes were prepared and the electrochemical characteristics of oxygen reduction and unit-cell performance were evaluated. The optimum condition of hot press to make electrode is 360$^{\circ}C$ and 10 kg/$\textrm{cm}^2$. Maximum performance was obtained at 30 wt% PTFE content in the catalyst layer with 80% utilization of platinum clusters. Unit-cell performance of hot pressed Pt/C electrode was 200 mA/$\textrm{cm}^2$ at 700 ㎷ and stable performance was maintained more than 200 hr.

• Journal of Oriental Neuropsychiatry
• /
• v.22 no.2
• /
• pp.107-128
• /
• 2011

Objectives : This experiment was designed to investigate the efficacy of DDTCMT hot water extract & ultra-fine powder on Alzheimer's Disease Model. Methods : The effects of the DDTCMT hot water extract on expression of IL-$1{\beta}$, IL-6, TNF-${\alpha}$, COX-2, NOS-II, IL-10, IL-1 receptor antagonist mRNA and production of IL-$1{\beta}$, IL-6, TNF-${\alpha}$ in BV2 microglial cell line treated by lipopolysacchaide(LPS) were investigated. Expression of NO, ROS in BV2 microglial cell line treated by LPS and AChE activity in PC-12 cell treated by NGF were investigated. anti-AChE was observed through Western blot analysis. The effects of the DDTCMT hot water extract & ultra-fine powder on the behavior of the memory deficit mice induced by scopolamine were investigated. Results : 1. The DDTCMT hot water extract significantly decreased the production of mIL-6, mNOS-II, mTNF-${\alpha}$, and increased the production of mIL-10, mIL-1 receptor antagonist. 2. The DDTCMT hot water extract significantly suppressed the production of IL-$1{\beta}$, IL-6, TNF-${\alpha}$ in BV2 microglial cell line treated by LPS. 3. The DDTCMT hot water extract significantly suppressed the NO and ROS production in BV2 microglial cell line treated by LPS. 4. The DDTCMT hot water extract groups showed inhibition of AChE activity in NGF treated PC-12 cell line. 5. The DDTCMT hot water extract suppressed anti-AChE expression in NGF treated PC-12 cell line was observed by Western blot analysis. 6. The DDTCMT hot water extract & ultra-fine powder groups showed significantly inhibitory effect on the scopolamine -induced impairment of memory in the experiment of Morris water maze. Conclusions : These results suggest that the DDTCMT hot water extract & ultra-fine powder may be effective for the prevention and treatment of Alzheimer's disease.

• Food Science and Biotechnology
• /
• v.17 no.6
• /
• pp.1185-1190
• /
• 2008

When 10 kinds of herbal medicines were fractionated into hexane, MeOH, cold-water, and hot-water extracts, hot-water extracts from Acanthopanax senticosus (AS), Glycyrrhiza uralensis (GU), Cichorium intybus (CI), and Polygonatum odoratum (PO) showed the potent intestinal immune system modulating activity (1.72-, 1.62-, 1.60-, and 1.53-fold of control at $100{\mu}g/mL$, respectively). Especially, hot-water extracts from AS (215% compared with the control) and GU (187%) also had macrophages stimulating activity and mitogenic activity of splenocytes (7.1- and 6.5-fold) at $100{\mu}g/mL$. In addition, the effects of hot-water extracts from herbal medicines on anticancer activities were studied in mice. Hot-water extracts from AS and GU enhanced cytotoxicity of natural killer cell against cancer cell, Yac-1 (37 and 34% cytotoxicity) at E/T ratio 100:1, and colon 26-M3.1 cancer cell lines had significantly inhibited (82.1 and 75.2%) in experimental lung metastasis. These results suggest that hot-water extracts from A. senticosus and G. uralensis can be used as biological response modifiers to stimulate immune system and inhibit tumor.

• Microbiology and Biotechnology Letters
• /
• v.25 no.2
• /
• pp.178-182
• /
• 1997

This study was carried out particutarly focusing on the antitumor effects of extracts obtained from mushroom, Daedalea dickinsii against Hela cell, Hep $G_{2}$, cell, L 929 cell and Sarcoma-180. Antitumor effect of hot water extracts obtained from Daedalea dickinsii against Hela cell showed at the highest level of 70% when adiministrated at the concentration of 1.5 mg/100 ml, however Hep $G_{2}$, cell inhibited 40% at the same concentration of hot water extracts. Antitumor effects of methanol extract of Daedalea dickinsii against Hela cell indicated at the highest level of 60% when 4 mg/ml was administerated. Antitumor effect of hot water extract of Daedalea dickinsii inhibited 51.03% against L929 cell. The solid tumor sarcoma-180 growth inhibition of methanol extract of Deadalea dickinsii inhibited 45.67% when administrated at the concentration of 60mg/kg, and the life prolongation was higher 30.88% than that control group.

• Proceedings of the KWS Conference
• /
• 2006.10a
• /
• pp.89-91
• /
• 2006

An analysis of a multi-pin remote welding for a DUPIC fuel fabrication was made to establish the optimum welding processes in a hot cell environment. An initial investigation for hands-on fabrication outside the hot cell was performed, and the constraints of a hot cell welding were considered. Preliminary welding performances to improve the RW process were also examined. The RW process was determined to be the best in a hot cell environment for joining the end plate to the end caps. This paper presents an outline of the developed RW machine for a DUPIC fuel fabrication and compares the characteristics of a Zr-4 end plate welding by using electrical resistance and LB methods. The weld nuggets of RW specimens and torque strengths of resistant and LB welded zones were also investigated.

• 제어로봇시스템학회:학술대회논문집
• /
• 2002.10a
• /
• pp.100.6-100
• /
• 2002

The crane and the master-slave manipulators (MSM) are widely used as a remote handling device in nuclear facilities such as the hot cell. The equipment to be installed in the hot cell should be optimally placed within the workspace of the wall-mounted slave manipulator for the maintenance operation. Also, the slave manipulator with the end effectors should be properly positioned and oriented for the dedicated maintenance operation. Hence, the workspace and the motion of the slave manipulator, as well as, the remote operation task should be analyzed before installing the manipulators and the hot cell equipment. For this purpose, the 3D graphic simulator, which simulates the remote operation o...

• Journal of Welding and Joining
• /
• v.21 no.6
• /
• pp.20-25
• /
• 2003

Various welding methods such as Gas Tungsten Arc Welding(GTAW), magnetic force electrical resistance welding and Laser Beam Welding(LBW) are now available for end cap closure of nuclear fuel rods. Even though the resistance and GTA welding processes are widely used in manufacturing commercial fuel rods, they can not be recommended for the remote seal welding of fuel rods in the hot cell Facility due to the complexity of the electrode alignment, the difficulty in replacing parts in a remote manner and the large heat input for the thin sheath. Therefore, the Nd:YAG laser system using optical fiber transmission was selected for the end cap welding of irradiation fuel rods in the hot cell. The remote laser welding apparatus in the hot cell Facility was developed using a pulsed Nd:YAG laser of 500 watt average power with an optical fiber transmission. The weldment quality such as microstructure and mechanical strength was satisfactory. The optimum conditions of laser welding for encapsulating irradiation fuel rods in the hot cell were obtained.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2003.11a
• /
• pp.337-344
• /
• 2003

In this study, the maintenance process by the servo manipulator for the parts of the equipment that cannot be reached by MSM in the hot cell was developed. To do this, the virtual mock up is implemented using virtual prototyping technology. And, Using this mock-up, the workspace of the manipulators In the hot cell and the operator's view through the wall-mounted lead glass are analyzed. And the path planning of the servo manipulator using the collision detection of the virtual mockup is established. Also, the maintenance process for the parts of the equipment that are located out area of the MSM's workspace by the servo manipulator is proposed and verified through the graphic simulation. The proposed remote maintenance process of the equipment can be effectively used in the real hot cell operation. Also, the implemented virtual mock-up of the hot cell can be effectively used in analyzing the various hot cell operation and in enhancing the reliability and safety of the spent fuel management.

• Journal of Communications and Networks
• /
• v.6 no.3
• /
• pp.216-225
• /
• 2004

In a cellular network, if there are too many data users in a cell, data may suffer long delay, and system's quality-of-service (QoS) will degrade. Some traditional schemes such as dynamic channel-allocation scheme (DCA) will assign more channels to hot (or overloaded) cells through a central control system (CC) and the throughput increase will be upper bounded by the number of new channels assigned to the cell. In mobile-assisted data forwarding (MADF), we add an ad-hoc overlay to the fixed cellular infrastructure and special channels-called forwarding channels- are used to connect mobile units in a hot cell and its surrounding cold cells without going through the hot cell's base station. Thus, mobile units in a hot cell can forward data to other cold cells to achieve load balancing. Most of the forwarding-channel management work in MADF is done by mobile units themselves in order to relieve the load from the CC. The traffic increase in a certain cell will not be upper bounded by the number of forwarding channels. It can be more if the users in hot cell are significantly far away from one another and these users can use the same forwarding channels to forward data to different cold neighboring cells without interference. We find that, in a system using MADF, under a certain delay requirement, the throughput in a certain cell or for the whole net-work can be greatly improved.