• Journal of Intelligence and Information Systems
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• v.27 no.1
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• pp.191-207
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• 2021

Up to this day, mobile communications have evolved rapidly over the decades, mainly focusing on speed-up to meet the growing data demands of 2G to 5G. And with the start of the 5G era, efforts are being made to provide such various services to customers, as IoT, V2X, robots, artificial intelligence, augmented virtual reality, and smart cities, which are expected to change the environment of our lives and industries as a whole. In a bid to provide those services, on top of high speed data, reduced latency and reliability are critical for real-time services. Thus, 5G has paved the way for service delivery through maximum speed of 20Gbps, a delay of 1ms, and a connecting device of 106/㎢ In particular, in intelligent traffic control systems and services using various vehicle-based Vehicle to X (V2X), such as traffic control, in addition to high-speed data speed, reduction of delay and reliability for real-time services are very important. 5G communication uses high frequencies of 3.5Ghz and 28Ghz. These high-frequency waves can go with high-speed thanks to their straightness while their short wavelength and small diffraction angle limit their reach to distance and prevent them from penetrating walls, causing restrictions on their use indoors. Therefore, under existing networks it's difficult to overcome these constraints. The underlying centralized SDN also has a limited capability in offering delay-sensitive services because communication with many nodes creates overload in its processing. Basically, SDN, which means a structure that separates signals from the control plane from packets in the data plane, requires control of the delay-related tree structure available in the event of an emergency during autonomous driving. In these scenarios, the network architecture that handles in-vehicle information is a major variable of delay. Since SDNs in general centralized structures are difficult to meet the desired delay level, studies on the optimal size of SDNs for information processing should be conducted. Thus, SDNs need to be separated on a certain scale and construct a new type of network, which can efficiently respond to dynamically changing traffic and provide high-quality, flexible services. Moreover, the structure of these networks is closely related to ultra-low latency, high confidence, and hyper-connectivity and should be based on a new form of split SDN rather than an existing centralized SDN structure, even in the case of the worst condition. And in these SDN structural networks, where automobiles pass through small 5G cells very quickly, the information change cycle, round trip delay (RTD), and the data processing time of SDN are highly correlated with the delay. Of these, RDT is not a significant factor because it has sufficient speed and less than 1 ms of delay, but the information change cycle and data processing time of SDN are factors that greatly affect the delay. Especially, in an emergency of self-driving environment linked to an ITS(Intelligent Traffic System) that requires low latency and high reliability, information should be transmitted and processed very quickly. That is a case in point where delay plays a very sensitive role. In this paper, we study the SDN architecture in emergencies during autonomous driving and conduct analysis through simulation of the correlation with the cell layer in which the vehicle should request relevant information according to the information flow. For simulation: As the Data Rate of 5G is high enough, we can assume the information for neighbor vehicle support to the car without errors. Furthermore, we assumed 5G small cells within 50 ~ 250 m in cell radius, and the maximum speed of the vehicle was considered as a 30km ~ 200 km/hour in order to examine the network architecture to minimize the delay.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.293-298
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• 2014

This study conducted experiments on the reclaimed land of Saemangeum located in Jeongrabuk-do in order to gain basic information about growth characteristics and yield ability according to soil salinity. Having soil excluding salt as a control group, this study adjusted the specimens' soil salinity to level 4 and then planted four varieties including Ilmichal Corn to investigate the growth or grain yield according to salinity. About the corn establishment rate according to soil salinity, over 97% up to $3.2dS\;m^{-1}$ was established, and then, it was reduced gradually according to the increase of concentration. According to the salt concentration of soil more required growth duration from seeding to heading comparing to non-treatment salt was delayed, at $1.6dS\;m^{-1}$, two days were delayed, at $3.2dS\;m^{-1}$, four to six days were delayed differently by varieties, and at $4.8dS\;m^{-1}$, six to 10 days were delayed. About the plant fresh weight according to soil salinity, Chalok 4 and Eolrukchal indicated 93%~97% or so compared with the salt-free one at $1.6dS\;m^{-1}$, and Chalok No. 4 showed 79% at the salinity of $3.2dS\;m^{-1}$, too, and it was a relatively higher growth percentage than those of the other varieties. In terms of dried seed weight according to soil salinity, compared with the corns cultivated in the control group, averagely 12.1% was lowered at the time of cultivation at $1.6dS\;m^{-1}$, and $3.2dS\;m^{-1}$ 40% was lowered, and about 70% was lowered at $4.8dS\;m^{-1}$. According to the result of examining the point of time that dried seed start to reduce due to soil salinity with the regression equation, soil salinity which starts the reduction of grain weight is $1.67dS\;m^{-1}{\sim}2.18dS\;m^{-1}$, and it differs by varieties, and EC of 50% that the yield reduces in half is $2.96dS\;m^{-1}{\sim}4.45dS\;m^{-1}$. And the degree of influence on each of the growth factors according to soil salinity is founded to be in the order of establishment rate

• Clinical and Experimental Pediatrics
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• v.49 no.4
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• pp.368-374
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• 2006

Purpose : The prevalence of obesity in children is increasing rapidly. Epidemiologic studies suggest that obesity induced atherosclerosis may start in childhood. We investigated whether obese children show early abnormalities of the arterial wall and endothelial dysfunction. Methods : Thirty-eight obese children(14-16 years old of age, male, body mass index $29.40{\pm}3.18kg/m^2$) and forty-five age and sex-matched healthy control children(body mass index $18.43{\pm}1.01kg/m^2$) were enrolled. Their carotid artery intima-media thickness(IMT) and brachial artery flowmediated dilation(FMD) response were measured by high-quality ultrasound system, and compliance, distensibility, stiffness index, incremental elastic modulus and wall stress were calculated by equation. In addition, we looked at the relations between these arterial features and metabolic cardiovascular risk factors. Results : The obese children had significantly increased IMT($0.52{\pm}0.09mm$ vs $0.40{\pm}0.07mm$, P< 0.001) and markedly impaired FMD($7.35{\pm}7.78$ percent vs $20.34{\pm}16.81$ percent, P<0.001) than the healthy controls. But the compliance and distensibility were lower, and the stiffness index, incremental elastic modules and wall stress were higher in the obese group than the control group, but not statistically significantly. Body mass index was highly associated with increased IMT(r=0.612, P<0.001) and reduced FMD(r=-0.414, P<0.001). Conclusion : We showed the deleterious effect of child obesity on both early functional and structural atherosclerotic markers. The ultrasonic findings will be used for screening and follow up markers to identify high-risk patients among obese children.

• Journal of Acupuncture Research
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• v.17 no.2
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• pp.187-208
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• 2000

By the activation of ovary hormone, many morphological changes occur in the epithelial cell lines and muscle cells in rat uterus. These two cells in uterus are important to the implantation of embryo, maintaining pregnancy and starting parturition. One important change associated with the morphological change of these two cells in uterus is the change on prostaglandin(PG) metabolism. Its presence and synthesis in endometriurn and myometrium in uterus affects estrous cycle and the start of embryo implantation in uterus. It also performs as an important modulator in parturition. So the abnormally weak expression of PG causes difficulty during labor and over-expression causes pre-term labor. PG biosynthesis starts from either free or liberated arachidonic acids from membrane phospholipid by phospholipase. Such arachidonic acids are converted into PG catalyzed by Cyclooxygenase. Under normal physiological condition, Cyclooxygenase-1(COX-1) having 602 units of amino acids controls the synthesis of PG. It acts as a local hormone regulating vasomodulation of blood flow, flexible muscle movement, increasing the blood permeability and contributing the protective role in preserving integrity of the stomach lining and Cyclooxygenase-2 (COX-2) is induced by the inflammation, pregnancy and increased its expression until parturition. Lipid metabolite like PG is located in uterine and expression of COX-2 increased with pregnancy. Increased expression of COX proteins in epithelial cells and myometrial cells are told to increase the muscle contractility in uterus but decreased right after the labor in rat. It is a good sign indicating that COX proteins are deeply related to the start of labor. Currently, Several studies report the use of PG and COX-2 inhibitor as medication for controlled abortion or to prevent pre-term labor but they entail various side-effects. Our study proposed to suggest use of acupuncture as an another mediator to control abortion or pre-term labor without causing unnecessary side-effects by those medicines. Two acupuncture sites, LI-4 & SP-6 were selected due to their known efficacy. From the immunohistochemical staining of COX-2, normal expression of COX-2 protein in nonpregnant SD rat's uterus revealed that COX-2 protein was primarily detected in the lumina epithelial lining and in the epithelial cell lining contacting the stromal cells. High resolution optical microscopic scanning revealed distinguishable staining in the myometrial mucosa. LI-4 acupuncture administered nonpregnant rat's uterus showed strong expression for COX-2 in endometrium contacted with lumina epithelial lining of rat uterus and in myometrial mucosa. Stromal cells showed more staining than untreated nonpregnant rat's uterus and stronger staining in stromal cells contacting myometrial layer compared to untreated nonpregnant rat's uterus. SP-6 acupuncture administered nonpregnant rat's uterus showed weak expression for COX-2 in myometrial layers and stromal cells but no staining was visible in lumina epitheliai and glandular epithelial cells. Few stromal cells and myometrial mucosa were positively stained for COX-2. Pregnant SD rat's uterus was also immunostained for COX-2 expression after 18 days of pregnancy. Unlike to untreated nonpregnant rat's uterus, luminal epithelial cells were not positively stained for COX-2 but stronger staining for COX-2 was revealed in stromal cells. LI-4 acupunctured SD rat's uterus had very strong expression of COX-2 in luminal epithelial lining. Few stromal cells showed stronger positive COX-2 staining and myometrial layers also showed more expression than untreated pregnant rat. SP-6 acupuncture administered pregnant SD rat's uterus showed positive expression of COX-2 in epithelial cells of luminal mucosa layer but weaker than that of LI-4 acupuncture treatment's case. However, strong positive staining was revealed in stromal mucosa and myometrial layers. Virgin SD rat's uterus motility index during LI-4 acupuncture was 66.52 % (Prob〉T = 0.0197) compared to its motility before the acupuncture treatment but the motility index was slighdy elevated up to 79.58 % (Prob〉T = 0.1175) after the acupuncture. During the SP-6 acupuncture treatment for 30 minutes, uterus motility index was 90.52 % (Prob〉T = 0.1832) showing lesser decrement but consequently reached similar motility index decreasal to 79.95 % (Prob〉T = 0.0215) after the acupuncture treatment as LI-4 showed. LI-4 acupuncture tend to be a quick treatment to reducing the uterus motility in a virgin rat but eventually both two acupuncture administration created very similar reduction of uterus motility seeing the index after the both acupunctures. The uterus movement monitored during the LI-4 acupuncture administered for 30 minutes, Pregnant SD rat showed decreased motility down to 77.90 % (Prob〉 T = 0.0076) compared to uterus motility before the acupuncture and it continuously decreased down to 71.81 %(Prob〉T = 0.0214) after the removal of needle. The statistical analysis using paired t-test showed significance difference for both two motility indexs at =0.05. SP-6 acupuncture administered to pregnant SD rat also had similar pattern of decreasing uterus motility index down to 74.70 % (Prob〉T = 0.1730) during the initial 30 minutes acupuncture administration and it was continuously lowered to 71.52 % (Prob〉T = 0.0155) after the acupuncture. The paired t-test resuit for SP-6 suggest prompt response of uterus motility index to the SP-6 acupuncture treatment but consequently reached same level of inducing the motility reduction as LI-4 at =0.05 level.

• The Korean Journal of Pain
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• v.2 no.2
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• pp.155-166
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• 1989

Bonica defined, that reflex sympathetic dystrophy (RSD) may develop pain, vasomotor abnoramalities, delayed functional recovery, and dystrophic changes on an affected area without major neurologic injury following trauma, surgery or one of several diseased states. This 45 year old male patient had been crushed on his left shoulder by a heavily laden rear car, during his job street cleaning about 10 years ago (1978). At first the pain was localizea only to the site of injury, but with time, it spreaded from the shoulder to the elbow and hand, with swelling. X-ray studies in the local clinic, showed no bone abnormalities of the affected site. During about 10 years following the injury, the had recieved several types of treatments such as nonsteroidal analgesics, steroid injections into the glenoidal cavity (10 times), physical therapy, some oriental herb medicines, and acupuncture over a period of 1~3 months annually. His shoulder pain and it's joint dysfunction persisted with recurrent paroxysmal aggrevation because of being mismanaged or neglected for a sufficiently long period these fore permiting progression of the sympathetic imbalance. On July 14 1988 when he visited our clinic. He complained of burning, aching and had a hyperpathic response or hyperesthesia in touch from the shoulder girdle to the elbow and the hand. Also the skin of the affected area was pale, cold, and there was much sweating of the axilla and palm, but no edema. The shoulder girdle was unable to move due to joint pain with marked weakness. We confirmed skin temperatures $5^{\circ}C$ lower than those of the unaffected axilla, elbow and palm of his hand, and his nails were slightly ridged with lateral arching and some were brittle. On X-ray findings of both the shoulder AP & lateral view, the left humerus and joint area showed diffuse post-traumatic osteoporosis and fibrous ankylozing with an osteoarthritis-like appearance. For evaluating the RSD and it's relief of pain, the left cervical sympathetic ganglion was blocked by injecting 0.5% bupivacaine 5 ml with normal saline 5 ml (=SGB). After 15 minutes following the SGB, the clinical efficacy of the block by the patients subjective score of pain intensity (=PSSPI), showed a 50% reduction of his shoulder and arm pain, which was burning in quality, and a hyperpathic response against palpation by the examiner. The skin temperatures of the axilla and palm rose to $4{\sim}5^{\circ}C$ more than those before the SGB. He felt that his left face and upper extremity became warmer than before the SGB, and that he had reduced sweating on his axilla and his palm. Horner's sign was also observed on his face and eyes. But his deep shoulder joint pain was not improved. For the control of the remaining shoulder joint pain, after 45 minutes following the SGB, a somatic sensory block was performed by injecting 0.5% bupivacaine 6 ml mixed with salmon calcitonin, $Tridol^{(R)}$, $Polydyn^{(R)}$ and triamcinolone into the fossa of the acromioclavicular joint region. The clinical effect of the somatic block showed an 80% releif of the deep joint pain by the PSSPI of the joint motion. Both blocks, as the above mentioned, were repeated a total of 28 times respectively, during 6 months, except the steroid was used just 3 times from the start. For maintaining the relieved pain level whilst using both blocks, we prescribed a low dose of clonazepam, prazocin, $Etravil^{(R)}$, codeine, etodolac micronized and antacids over 6 months. The result of the treatments were as follows; 1) The burning, aching and hyperpathic condition which accompanied with vaosmotor and pseudomotor dysfunction, disappeared gradually to almost nothing, within 3 weeks from the starting of the blocks every other day. 2) The joint disability of the affected area was improved little by little within 6 months. 3) The post-traumatic osteoporosis, fibrous ankylosis and marginal sclerosis with a narrowed joint, showed not much improvement on the X-ray findings (on April 25, 1989) 10 months later in the follow-up. 4) Now he has returned to his job as a street cleaner.

• Journal of Life Science
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• v.24 no.6
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• pp.686-693
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• 2014

Restricted supply of nutrients may affect genes at the molecular level as well as physiological functions. Understanding the cellular responses during starvation is necessary for developing strategies to reduce damage caused by starvation stress. After 1 h of starvation, Got1 gene expression was increased but its expression returned to the normal state after 24 h. Mat1 gene expression continuously increased with starvation from 1 h until 24 hr. Rats starved for 1-3 days showed significant changes in expression of the Got1 and Mat1 genes, which were significantly reduced in the cerebral cortex and cerebellum. In the lung, gene expression was increased by starvation for 1-2 days but decreased on the third day. No differences were observed in gene expression in the heart. Strong Got1 lung gene expression was seen in the starvation group one day after restoration of the food supply. Muscle mass was significantly reduced at the start of starvation and remained the same after two days of starvation and one day after the food supply was restored. The Mat1 gene expression did not change. The Got1 was induced by NaCl and showed strong expression in the lung and the thymus, but the apparent decrease of the remaining changes were not observed in male rats. The Mat1 gene was not as sensitive as the Got1 gene to induction by NaCl. However, differences in gene induction by NaCl were evident between males and females, indicating that diet control of gene expression is associated with hormones.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.6
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• pp.427-446
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• 2008

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2006 has been accomplished. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environments. The conclusions are as follows. (1) The research trends of fluid engineering have been surveyed as groups of general fluid flow, fluid machinery and piping, etc. New research topics include micro heat exchanger and siphon cooling device using nano-fluid. Traditional CFD and flow visualization methods were still popular and widely used in research and development. Studies about diffusers and compressors were performed in fluid machinery. Characteristics of flow and heat transfer and piping optimization were studied in piping systems. (2) The papers on heat transfer have been categorized into heat transfer characteristics, heat exchangers, heat pipes, and two-phase heat transfer. The topics on heat transfer characteristics in general include thermal transport in a cryo-chamber, a LCD panel, a dryer, and heat generating electronics. Heat exchangers investigated include pin-tube type, plate type, ventilation air-to-air type, and heat transfer enhancing tubes. The research on a reversible loop heat pipe, the influence of NCG charging mass on heat transport capacity, and the chilling start-up characteristics in a heat pipe were reported. In two-phase heat transfer area, the studies on frost growth, ice slurry formation and liquid spray cooling were presented. The studies on the boiling of R-290 and the application of carbon nanotubes to enhance boiling were noticeable in this research area. (3) Many studies on refrigeration and air conditioning systems were presented on the practical issues of the performance and reliability enhancement. The air conditioning system with multi indoor units caught attention in several research works. The issues on the refrigerant charge and the control algorithm were treated. The systems with alternative refrigerants were also studied. Carbon dioxide, hydrocarbons and their mixtures were considered and the heat transfer correlations were proposed. (4) Due to high oil prices, energy consumption have been attentioned in mechanical building systems. Research works have been reviewed in this field by grouping into the research on heat and cold sources, air conditioning and cleaning research, ventilation and fire research including tunnel ventilation, and piping system research. The papers involve the promotion of efficient or effective use of energy, which helps to save energy and results in reduced environmental pollution and operating cost. (5) Studies on indoor air quality took a great portion in the field of building environments. Various other subjects such as indoor thermal comfort were also investigated through computer simulation, case study, and field experiment. Studies on energy include not only optimization study and economic analysis of building equipments but also usability of renewable energy in geothermal and solar systems.

• Radiation Oncology Journal
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• v.21 no.4
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• pp.261-268
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• 2003

Purpose: To report the results of curative treatment for patients with tonsil cancer by retrospective analysis. Materials and Methods: From Jan. 1995 till Dec. 2000, 27 patients with squamous cell carcinoma of the tonsil received curative treatment at Samsung Medical Center. Therapeutic decision was made through multidisciplinary conference, and curative radiation therapy was favored when, (1) the patient's condition was not fit for general anesthesia and surgery, (2) the patient refused surgery, (3) complete resection was presumed impossible, or (4) too severe disability was expected after surgery. Surgery was the main local modality in 17 patients (S$\pm$RT group), and radiation therapy in 10 (RT$\pm$CT group). The median follow-up period was 41 months. Results: AJCC stages were I/II in four, III in two, and IV in 21 patients. The 5-year disease-free survival rate was 73.3$\%$ in all patients, 70.6$\%$ in the S$\pm$RT group, and 77.8$\%$ in the RT$\pm$CT group. Treatment failure occurred in seven patients, all with stage III/IV, and all the failures occurred within 24 months of the start of treatment. Five patients among the S$\pm$CT group developed treatment failures; 2 local, 2 regional, and 1 distant (crude rate=29.4$\%$). Two patients among the RT$\pm$CT group developed failures; 1 synchronous local and regional, and 1 distant (crude rate=20.0$\%$). The 5-year overall survival rate was 77.0$\%$ in all patients, 80.9$\%$ in the S$\pm$RT group, and 70.0$\%$ in the RT$\pm$CT group. Conclusion: We could achieve favorable results that were comparable to previously reported data with respect to both the rates of local control and of survival by applying S$\pm$RT and RT$\pm$CT. RT$\pm$CT is judged to be an alternative option that can avoid the functional disability after surgical resection.