• Journal of Biosystems Engineering
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• v.14 no.4
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• pp.272-281
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• 1989

It is desirable for the vertical wind tunnel which can build uniform air flow across the vertical duct to be used for the purpose of the investigation of the aerodynamic properties of grains. This study was conducted to examine how the air velocity profile in the vertical duct is influenced by the various alternations of the elements of the wind tunnel, and to prepare design guidance of the vertical wind tunnel which can be used for investigating aerodynamic properties of grains. In addition, several tests were conducted to locate the test section which can be applicable for determining the terminal velocity of grain. The following conclusions were obtained from the study: 1. The size and the location of the outlet of the plenum chamber should be determined such that the outlet air flow is less affected by the air flow and the back pressure by the side wall of the chamber. 2. The honeycomb was not helpful for attaining uniform air flow in case that the air flow profile at the bottom of the vertical duct is serverely different from the ideal one. 3. Even though considerable pressure drop was resulted from the screens installed within the vertical duct, the screens were helpful for attaining uniform air flow in the duct. 4. It is desirable for the test section to be located at the position that not only the air flow of the duct is not disturbed by the distorted back pressure in the plenum chamber, but also less boundary layer is developed.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1491-1498
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• 2006

The feasibility of pullulan acetate nanoparticles (PAN) with ionic strength (IS) sensitivity as a radioisotope carrier to inhibit tumor growth is demonstrated. PAN was radiolabeled with rhenium 188 (Re-188) without any chelating agents. The labeling efficiency of Re-188 into PAN (Re-188PAN) was $49.3{\pm}4.0%$ as determined by TLC. The tumor volumes of mice treated with 0.45 mCi of Re-188-PAN were measured and compared with that of free Re-188 after 5 days of intratumoral injection. For the histological evaluation of apoptotic nuclei of tumor cells, hematoxylin and eosin (H&E), and terminal deoxynucleotidyl transferase biotinylated deoxyuridine triphosphate nick end labeling (TUNEL) staining were performed. The mean tumor volume of the Re-188-PAN-treated group was decreased by 36% after 5 days, whereas that the free Re-188-treated group was decreased by only 15% (P<0.05). The mean number of TUNEL-positive cells in Re-188-PAN-treated tumors at $144.3{\pm}79.9$ cells/section was significantly greater than the control ($26.7{\pm}7.9$ cells/section, P=0.03). The numbers of leukocyte and lymphocyte were decreased in both free Re-188- and Re-188-PAN-treated mice. These results indicated that the intratumoral injection of Re-188-PAN effectively inhibits the tumor growth by prolonging Re-188 retention time in tumor site induced by the IS sensitivity.

• Journal of Advanced Navigation Technology
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• v.24 no.6
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• pp.500-507
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• 2020

This paper presents a risk assessment methodology for standard flight procedures using recorded automatic dependent surveillance-broadcast (ADS-B) data. Utilizing the proposed methodology, the results of risk analyses in RKSI (incheon international airport) and RKSS (gimpo international airport) using trajectories that are regenerated based on 100 days of ADS-B data are presented. For the risk metric, detect and avoid well clear (DWC) is used. With this index, each procedure was evaluated for the sections with highest level of risk. Among the standard instrument departure (SID) of RKSI, the section between SI712 and RANOS of RNAV BOPTA 1L showed the highest level of risk. For the standard terminal arrival route (STAR) of RKSI, section between SI947 and DANAN of RNAV GUKDO 1N wasthe one with the highest level of risk. For RKSS, the segment between SS726 and SS727 of RNAV BULTI 1X and the segment between KAKSO and KALMA of RNAV OLMEN 1D showed the highest level of risk among the SIDs and STARs, respectivly.

• KEPCO Journal on Electric Power and Energy
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• v.8 no.1
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• pp.43-48
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• 2022

Although the distribution system has been structured as complicated as a mesh in the past, the connection points for each line are always kept open, so that it is operated as a radial distribution system (RDS). For RDS, the line utilization rate is determined according to the maximum load on the line, and the utilization rate is usually kept low. In addition, when a fault occurs in the RDS, a power outage of about 3 to 5 minutes occurs until the fault section is separated, and the healthy section is transferred to another line. To improve the disadvantages of the RDS, research on the construction of a networked distribution system (NDS) that linking multiple lines is in progress. Compared to the RDS, the NDS has advantages such as increased facility utilization, load leveling, self-healing, increased capacity connected to distributed generator, and resolution of terminal voltage drop. However, when a fault occurs in the network distribution system, fault current can flow in from all connected lines, and the direction of fault current varies depending on the fault point, so a high-precision fault current direction determination method and high-speed communication are required. Therefore, in this paper, we propose an accurate fault current direction determination method by comparing the peak value polarity of the fault current in the event of a fault, and a communication-based protection coordination method using this method.

• Smart Media Journal
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• v.13 no.1
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• pp.52-59
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• 2024

This paper proposes a plan to improve the reception radio environment of the mobile terminal and maintain a constant reception electric field by using small cells in a small closed environment. In order to configure an efficient communication infrastructure for small cells, both ends of wireless transmission and reception of an Ethernet-based wireless video recording system are connected using an L2 switch. The small cell connected to the receiving side L2 switch shares the wireless network section of the wireless video recording system and connects to the transmitting side L2 switch. After that, when it is normally linked to FMS, a management system for small cells, through the Internet network, the output of small cells is checked. In order to verify the results, a proposed network is formed on the elevator inside the building with a poor radio wave environment, and the radio wave environment is measured before and after the small cell application in the section where the elevator operates. As a result, the main parameters of the radio wave environment in all sections of the elevator are improved, as well as a constant receiving electric field strength within the moving elevator.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.290-298
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• 2017

This study compared the median nerve, ulnar never, and F waves of patients diagnosed with early Carpal Tunnel Syndrome to a control group to determine whether F waves could be a useful indicator in the diagnosis of early CTS. The terminal motor latency (TML), terminal motor amplitude and sensory nerve conduction velocity (SNCV) of the section from the palms to the wrists, which are the key indicators to use in a nerve conduction study, and F waves were compared with the control group using the t-test. A correlation analysis was performed to analyze the correlation between the main indicators. The comparison between the median nerve's TML of the early CTS patients and that of the control group shows that there are 2 sections which have high significance (p<0.001). In the comparison of the SNCV of the median nerve between the control group and early CTS patients, high significance was observed (p<0.001). In the analysis of the F waves, there was high significance (p<0.001) between the control group and early CTS patients for the median nerve, but not for the ulnar nerve. The correlation analysis revealed that both the SNCV-TML and F wave-TML had significance. These results suggested that, along with TML and SNCV, F waves can be a useful indicator to diagnose CTS.

• Journal of Navigation and Port Research
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• v.26 no.1
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• pp.112-119
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• 2002

In accordance with the development plans of Jeju for international free city, Jeju new harbor will be constructed cosidering supporting Jeju city as an international tour city, safe arrival and departure at the terminal of 80.000G/T cruise ship. In this study, we used a full-mission ship handling simulator adopting 80.000G/T cruise ship manoeuvered at the planned Juju international cruise terminal. Five masters who have had a long experience of shop maneuvering ware called to carry out the simulations of which No. 1 , Np. 2, and No.4 scenario of simulation were tried twice, completed the total of 10 times and No.3 scenario of simulation once, reached at the total of 5 time. The marine traffic safety was assessed in terms of 1) the closest point of approach(CPA) to breakwater and quay in the vicinty and the probability of crossing fairway limit, 2)subjective evaluation such as the mental burden and the maneuvering disfficulty of shiphanders and 3) the opinions of shiphandlers. From th result of this simulation, we have a conclusion that the 80.000G/T cruise ship can be maneuvered safely at the planned terminal.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.869-881
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• 1999

Inchon International Airport Elevated Road Way is located between the Passenger Terminal Building and Transportaion Center which are Inchon International Airport core construction projects. The deck of the bridge is consists of 5-span or 6-span continuous pre-stressed concrete slab. Steel form has been used to enhance the quality of texture on concrete slab. Steel form has been used to enhance the quality of texture on concrete surface, lower surface of deck slab with the two way arch has been manufactured by highly professional manner in order to get an beautiful exterior architectural looks. The prestressed concrete deck slab is mass concrete structures with a high-specified concrete strength and a varying section in the range of 0.95-2.8m thickness. Therefore high risks of thermal cracking occurrence by heat of hydration highly are expected. To resolve such problem, we adopted type 1 cement and pipe cooking method at construction site through mass concrete specimen test and 3-dimensional analysis. For Pipe cooling we used 25mm diameter stainless pipes with wrinkles. Cooling pipe with spacing 50-60cm has been installed. And continuous pipe cooling with cooling water of 15$^{\circ}C$ was conducted for 2days. In present 8 span of all 29 spans construction has been completed. No thermal cracking heat hydration has been observed yet.

• Advances in pediatric surgery
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• v.1 no.2
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• pp.177-180
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• 1995

A 2-day-old male (Premie, Large for gestational age(LGA), Intrauterine period(IUP) 33 weeks, birth weight 2,955 gram) was transferred with marked abdominal distention, bilious return via the orogastric tube, respiratory difficulty, and generalized edema (hydrops fetalis). He was born by cesarean section to a 36 year-old mother. Antenatal ultrasonogram at IUP 31 weeks demonstrated multiple dilated bowel loops suggestive of intestinal obstruction. There was no family history of cystic fibrosis. Simple abdominal films disclosed diffuse haziness and suspicious fine calcifications in the right lower quadrant. Barium enema demonstrated a microcolon. Sweat chloride test was not available in our institution. At laparotomy, there noted 1) a segmental volvulus of the small bowel with gangrenous change, associated with meconium peritonitis, 2) an atresia of the ileum at the base of the volvulus, and 3) the terminal ileum distal to the volvulus was narrow and impacted with rabbit pellets-like thick meconium. These findings appeared to be very similar to those of a complicated meconium ileus. In summary, the ileal atresia and meconium peritonitis seemed to be caused by antenatal segmental volvulus of the small intestine in a patient with probable meconeum ileus.

• Biomedical Science Letters
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• v.8 no.3
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• pp.161-165
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• 2002

Apoptosis can be difficult to detect in routine histological sections. Since extensive DNA fragmentation is an important characteristic of this process, visualization of DNA breaks could greatly facilitate the identification of apoptotic cells. Several techniques for the qualitative and quantitative detection of this process have been established; recently, an in situ nick end-labelling technique based on the detection of DNA fragmentation, which is a molecular characteristic of apoptotic cell death, was described. Applying this method to paraffin sections of rat tissues, sensitivity was observed to be inconsistently low with regard to the expected number of apoptotic cells. I describe a new modified method for formalin-fixed, paraffin-embedded tissue sections, pretense pretreatment to permeate the tissue sections that involves an TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling) is acknowledged as a method of choice in the rapid identification and quantification of the apoptotic cell fraction in paraffin tissue preparations. TUNEL was performed without apoptosis and with apopotosis samples to each of the three concentrations of proteinase K (10, 25, 40 mg/ml) pretreatments. In this study, I show that chemical pretreatments of the tissue sections in proteinase K (25 mg/ml for 15 min at room temperature) considerably enhances the sensitivity of this nick end labelling technique.