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A Study of the Characteristics of Heavy Rainfall in Seoul with the Classification of Atmospheric Vertical Structures (대기연직구조 분류에 따른 서울지역 강한 강수 특성 연구)

  • Nam, Hyoung-Gu;Guo, Jianping;Kim, Hyun-Uk;Jeong, Jonghyeok;Kim, Baek-Jo;Shim, Jae-Kwan;Kim, Byung-Gon
    • Journal of the Korean earth science society
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    • v.40 no.6
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    • pp.572-583
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    • 2019
  • In this study, the atmospheric vertical structure (AVS) associated with summertime (June, July, and August) heavy rainfall in Seoul was classified into three patterns (Loaded Gun: L, Inverted V: IV, and Thin Tube: TT) using rawinsonde soundings launched at Osan from 2009 to 2018. The characteristics of classified AVS and precipitation property were analyzed. Occurrence frequencies in each type were 34.7% (TT-type), 20.4% (IV-type), 20.4% (LG-type), and 24.5% (Other-type), respectively. The mean value of Convective Available Potential Energy (1131.1 J kg-1) for LG-types and Storm Relative Helicity (357.6 ㎡s-2) for TT-types was about 2 times higher than that of other types, which seems to be the difference in the mechanism of convection at the low level atmosphere. The composited synoptic fields in all cases showed a pattern that warm and humid southwesterly wind flows into the Korean Peninsula. In the cases of TT-type, the low pressure center (at 850 hPa) was followed by the trough in upper-level (at 500 hPa) as the typical pattern of a low pressure deepening. The TT-type was strongly influenced by the low level jet (at 850 hPa), showing a pattern of connecting the upper- and low-level jets. The result of analysis indicated that precipitation was intensified in the first half of all types. IV-type precipitation induced by thermal instability tended to last for a short term period with strong precipitation intensity, while TT-type by mechanical instability showed weak precipitation over a long term period.

Effect of Pesticide Residues on Perilla Leaf by Nozzle Types of Knapsack Sprayers (배부식 분무기 노즐이 들깻잎의 농약잔류에 미치는 영향)

  • Son, Kyeong-Ae;Kang, Tae Kyeong;Park, Byeong Jun;Jin, Yong-Duk;Gil, Geun-Hwan;Kim, Chan Sub;Kim, Jin Bae;Im, Geon-Jae;Lee, Key-Woon
    • The Korean Journal of Pesticide Science
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    • v.16 no.4
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    • pp.282-287
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    • 2012
  • This study was carried out to clarify the effects of the application of pesticide by different spray nozzle types on pesticide residues. The average droplet size and discharge rate were investigated when the manual compressed sprayer with two head disk type nozzle and the knapsack engine powered sprayer with two head fan shape nozzles were used. The fan type nozzles were classified into three types by the number of orifice in the nozzle. Three type nozzles tested were fan with one orifice, fan with two orifices and fan with three orifices. Fan (trade name : D-3) with 2.4 L/min. of the discharge rate and $76{\mu}m$ of the average droplet size while maintaining constant pressure $1.1{\pm}0.2$ MPa, and fan D-35 with 2.6 L/min. and $90{\mu}m$ while maintaining constant pressure $1.0{\pm}0.2$ MPa were appropriate. The orifice size of D-3 was 0.65 mm length ${\times}$ 0.45 mm width and the orifice size of D-35 was 0.62 mm length ${\times}$ 0.46 mm width. The residue levels of imidacloprid on perilla leaves among four applications by four different nozzles show significantly difference with 5% significance level. The residue levels $3.76{\sim}3.92mg\;kg^{-1}$ by fan or disk type is smaller than $4.52{\sim}4.92mg\;kg^{-1}$ by fan II or fan III. The residue levels of imidacloprid on perilla leaf were different depend on the spray nozzles type.

Meta-Analysis on Effectiveness of Intervention to Improve Patient Compliance in Korean (한국인 치료순응도 향상을 위한 개입 효과에 대한 메타분석)

  • 김춘배;조희숙;현숙정;박애화
    • Health Policy and Management
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    • v.12 no.2
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    • pp.23-42
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    • 2002
  • The purpose of this study was to analyze the results of 133 studies related to patient compliance published between 1980 and 2001 and to assess the effectiveness of intervention on compliance by using meta-analysis. We collected the existing literatures by using web and manual search 'patient compliance', 'sick role behavior', 'major clinical disease', and 'intervention' as key words and by reviewing content of journals related to medicine, nursing and public health. The compliance interventions were classified by theoretical focus into educational, behavioral, and affective categories within which specific intervention strategies were further distinguished. The compliance indicators broadly represent five classes of compliance-related assessments: (1) health outcomes (eg, blood pressure and hospitalization), (2) direct indicators (eg, urine and blood tracers and weight change), (3) indirect indicators (eg, pill count and refill records), (4) subjective report (eg, patients' or others' reports), (5) utilization (appointment making and keeping, use of preventive services). Quantitative meta-analysis was performed by MetaKorea program which was developed for meta-analysis in Korea. Among the 133 articles, 10 studies were selected through the qualitative meta-analysis process, and then only 6 studies were selected for the quantitative meta-analysis finally. The interventions produced significant effects for all the compliance indicators with the magnitude of common effect size (4.1192) than the non-intervention group in a random effect model. The largest effects were each study for patient of hypertension using health outcome such as blood pressure (0.4679) and diabetes mellitus using direct indicator such as glucose level in blood and urine (0.7753). These results suggest that strategic interventions showed clear advantage for improvement of patient compliance compared with non-intervention group.

Effects of Compositions of Saponin Fraction from Korean Red Ginseng in the Relaxation of Rabbit and Rat Corpus Cavernosum (토끼와 흰쥐 음경해면체 이완작용에 미치는 홍삼사포닌 분획별 효과)

  • Choi Young Deuk;Park Jin Ah;Choi Hyung Ki;Nam Ki Yeul
    • Journal of Ginseng Research
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    • v.23 no.1 s.53
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    • pp.13-20
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    • 1999
  • We previously reported that Korean red ginseng (KRG) has a relaxation effect on the smooth muscles of corpus cavernosum via nitric oxide (NO) pathway and calcium and potassium channels. However, it is suggested that the active ingredients of KRG might be different depending on the sources of preparation, and there might be differences in actions for different compositions. We first investigated the composition of KRG saponins according to the extractions of the various sources of KRG, then with these extractions the relaxation effects were evaluated in vitro and hemodynamical in vivo using New Zealand white rabbit and rat corpus cavernosum. The total compositions of ginsenoside $(G-Rb_1,\;-Rb_2,\;-Rc,\;-Rd,\;G-Re,\;-Rf,\;-Rg_1)$ in fractionated KRG saponin designated as TS-1, TS-2, TS-3 were $41\%,\;40\%,\;and\;62\%,$ respectively, and the ratios of PD saponin and PT saponin (PD/PT) were 1,55, 1.72, 2.25, and 2.61, the values of which were statistically significant. In vitro studies using the rabbit corpus cavernosal muscle strips, the KRG saponin relaxed cavernosal strips in a dose-dependent manner, and same results were observed in in vivo studies, that KRG saponin increased the intracavernosal pressure in the rat. There was difference in the efficacy according to fractionation techniques. The differences in the total contents of ginsenosides did not affect relaxation, rather PT saponin content was statistically related to the degree of cavernosal relaxation, and this action presumed to be mediated by NO pathway and calcium and potassium channels. In conclusion, KRG exerts relaxation which is a key step in erection via combination of effects on NO system or calcium and potassium channels. The efficacy of this action is different to the sources of ginseng, which is affected by the different composition of ginsenosides $(G-Rb_1,\;-Rb_2,\;-Rc,\;-Rd,\;G-Re,\;-Rf,\;-Rg_1).$ Thus the further studies on the active ingredients such as minor ginsenosides and non-saponin components of red ginseng with maximum potency should be sought.

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Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2016 (설비공학 분야의 최근 연구 동향 : 2016년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.6
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    • pp.327-340
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    • 2017
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2016. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of flow, heat and mass transfer, the reduction of pollutant exhaust gas, cooling and heating, the renewable energy system and the flow around buildings. CFD schemes were used more for all research areas. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results of the long-term performance variation of the plate-type enthalpy exchange element made of paper, design optimization of an extruded-type cooling structure for reducing the weight of LED street lights, and hot plate welding of thermoplastic elastomer packing. In the area of pool boiling and condensing, the heat transfer characteristics of a finned-tube heat exchanger in a PCM (phase change material) thermal energy storage system, influence of flow boiling heat transfer on fouling phenomenon in nanofluids, and PCM at the simultaneous charging and discharging condition were studied. In the area of industrial heat exchangers, one-dimensional flow network model and porous-media model, and R245fa in a plate-shell heat exchanger were studied. (3) Various studies were published in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, subjects include mobile cold storage heat exchanger, compressor reliability, indirect refrigeration system with $CO_2$ as secondary fluid, heat pump for fuel-cell vehicle, heat recovery from hybrid drier and heat exchangers with two-port and flat tubes. In the alternative refrigeration/energy system category, subjects include membrane module for dehumidification refrigeration, desiccant-assisted low-temperature drying, regenerative evaporative cooler and ejector-assisted multi-stage evaporation. In the system control category, subjects include multi-refrigeration system control, emergency cooling of data center and variable-speed compressor control. (4) In building mechanical system research fields, fifteenth studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, renewable energies, etc. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which could be help for improving the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the analyses of indoor thermal environments controlled by portable cooler, the effects of outdoor wind pressure in airflow at high-rise buildings, window air tightness related to the filling piece shapes, stack effect in core type's office building and the development of a movable drawer-type light shelf with adjustable depth of the reflector. The subjects of building energy were worked on the energy consumption analysis in office building, the prediction of exit air temperature of horizontal geothermal heat exchanger, LS-SVM based modeling of hot water supply load for district heating system, the energy saving effect of ERV system using night purge control method and the effect of strengthened insulation level to the building heating and cooling load.

Short-lasting headaches in children and adolescents (소아청소년에서 short-lasting headaches)

  • Rho, Young-il
    • Clinical and Experimental Pediatrics
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    • v.52 no.8
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    • pp.869-874
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    • 2009
  • Purpose : Short attacks of headache are present in the pediatric age group. Short-lasting headaches (SLH) have been infrequently reported in children and adolescents. This study aims to assess the prevalence, clinical characteristics, treatment, and prognosis of short-lasting headaches in children and adolescents. Methods : One hundred twenty-three consecutive patients attended the Chosun University Hospital Headache Center between March 2006 and July 2007. Among 123 headache patients, 44 patients with one key criterion, namely, recurrent headaches episodes of a few seconds to less than 30 minutes, were selected. Results : Of the 123 headache patients, 44 (35.8%, males 18, females 26) had SLH. The mean age was 9.24 years (range 2.3-14.2). The mean headache frequency was $11.50{\pm}10.30$ per month, mean severity was $4.86{\pm}1.36$ out of 10, and the mean PedMIDAS score was $7.97{\pm}17.51$. SLH was significantly more common in children <6 years old (10/22, 45.5%) than in ${\geq}6$ years old (34/101, 33.7%) (P=0.015). The nature of pain was pressure in 30.2%, stabbing in 27.9%, throbbing in 18.6%, and dull in 11.7%. In 52.4% patients, the pain occurred in the front, one side of the temple in 28.5%, both sides of the temple in 7.1%, and back in 4.8% patients. The duration of attacks was <6 minutes in 38% and ${\geq}6$ minutes in 61.4%. The intensity of the pain was 4-6 out of 10 in 75.0%, in 13.6% 1-3, and in 11.4% 7-10. Treatment was significantly effective in reducing the frequency, duration, and severity of headaches and the PedMIDAS score after 3 months (P<0.05). Conclusion : Short attacks of headache are common (35.8%) in children and adolescents. These are difficult to classify according to International Headache Society criteria. The outcome, after a period of 3 months to 2 years, was favorable in most patients. Further studies are needed to gather more data and to obtain a better description of these forms of headache in the pediatric group.

Development of a Nutrition Questionnaire and Guidelines for the Korea National Health Screening Program for Infants and Children (영유아 건강검진 영양 문진 및 지침 개발)

  • Moon, Jin-Soo;Kim, Jae-Young;Chang, Soo-Hee;Choi, Kwang-Hae;Yang, Hye-Ran;Seo, Jeong-Kee;Ko, Jae-Sung;Choi, Kyung-Dan;Seo, Jeong-Wan;Chung, Hee-Jung;Eun, Baik-Lin;Hwang, Seung-Sik;Seo, Soon-Ryu;Kim, Han-Suk
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.11 no.1
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    • pp.42-55
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    • 2008
  • Purpose: A new health policy, referred to as the National Health Screening Program for Infants and Children, was launched in November 2007 by the Ministry of Health and Welfare and National Health Insurance Corporation in Korea. We have developed a nutrition-counseling program that was incorporated into this project. Methods: We reviewed the nutritional guidelines published by The Korean Pediatric Society and internationally well-known screening programs such as Bright Future in the United States. We also reviewed the recent Korean national surveys on nutritional issues, including the Korea National Health and Nutrition Examination Survey (KNHANES) and the 2005 National Survey of Physical Body and Blood Pressure in Children and Adolescents. The development of questions, pamphlets, computer programs, and manuals for doctors was carried out after several meetings of researchers and governmental officers. Results: We summarized the key nutritional issues according to age, including breastfeeding in infants, healthier complementary feeding, and prevention of iron deficiency anemia, establishment of healthier diets, as well as dietary prevention of overweight children with an emphasis on physical exercise. We have constructed a new Korean nutrition questionnaire and an anticipatory guidance program based on the primary care schedule of visits at 4, 9, 18, 30, and 60 months of age. Five to eight questions were asked at each visit and age-matched pamphlets for parents and guidelines for doctors were provided. Conclusion: We developed a nutrition-counseling program based on recent scientific evidence for Korean infants and children. Further research on this national program for screening the nutritional problems in detail and setting the therapeutic approaches may help identify areas of success as well as those that need further attention.

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Leaf Shape Index, Growth, and Phytochemicals in Two Leaf Lettuce Cultivars Grown under Monochromatic Light-emitting Diodes (단색 발광다이오드에서 자란 축면상추 두 품종의 엽형, 생장 및 기능성 물질)

  • Son, Ki-Ho;Park, Jun-Hyung;Kim, Daeil;Oh, Myung-Min
    • Horticultural Science & Technology
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    • v.30 no.6
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    • pp.664-672
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    • 2012
  • As an artificial light source, light-emitting diode (LED) with a short wavelength range can be used in closed-type plant production systems. Among various wavelength ranges in visible light, individual light spectra induce distinguishing influences on plant growth and development. In this study, we determined the effects of monochromatic LEDs on leaf shape index, growth and the accumulation of phytochemicals in a red leaf lettuce (Lactuca sativa L. 'Sunmang') and a green leaf lettuce (Lactuca sativa L. 'Grand rapid TBR'). Lettuce seedlings grown under normal growing conditions ($20^{\circ}C$, fluorescent lamp + high pressure sodium lamp, $130{\pm}5{\mu}mmol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 hours photoperiod) for 18 days were transferred into incubators at $20^{\circ}C$ equipped with various monochromatic LEDs (blue LED, 456 nm; green LED, 518 nm; red LED, 654 nm; white LED, 456 nm + 558 nm) under the same light intensity and photoperiod ($130{\pm}7{\mu}mmol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 hours photoperiod). Leaf length, leaf width, leaf area, fresh and dry weights of shoots and roots, shoot/root ratio, SPAD value, total phenolic concentration, antioxidant capacity, and the expression of a key gene involved in the biosynthesis of phenolic compounds, phenylalanine ammonia-lyase (PAL), were measured at 9 and 23 days after transplanting. The leaf shape indexes of both lettuce cultivars subjected to blue or white LEDs were similar with those of control during whole growth stage. However, red and green LEDs induced significantly higher leaf shape index than the other treatments. The green LED had a negative impact on the lettuce growth. Most of growth characteristics such as fresh and dry weights of shoots and leaf area were the highest in both cultivars subjected to red LED treatment. In case of red leaf lettuce plants, shoot fresh weight under red LED was 3.8 times higher than that under green LED at 23 days after transplanting. In contrast, the accumulation of chlorophyll, phenolics including antioxidants in lettuce plants showed an opposite trend compared with growth. SPAD value, total phenolic concentration, and antioxidant capacity of lettuce grown under blue LED were significantly higher than those under other LED treatments. In addition, PAL gene was remarkably activated by blue LED at 9 days after transplanting. Thus, this study suggested that the light quality using LEDs is a crucial factor for morphology, growth, and phytochemicals of two lettuce cultivars.

Effect of pore-water salinity on freezing rate in application of rapid artificial ground freezing to deep subsea tunnel: concentration of laboratory freezing chamber test (고수압 해저터널에 급속 인공동결공법 적용시 간극수의 염분 농도가 동결속도에 미치는 영향 평가: 실내 동결챔버시험 위주로)

  • Oh, Mintaek;Lee, Dongseop;Son, Young-Jin;Lee, In-Mo;Choi, Hangseok
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.18 no.5
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    • pp.401-412
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    • 2016
  • It is extremely difficult to apply conventional grouting methods to subsea tunnelling construction in the high water pressure condition. In such a condition, the rapid artificial freezing method can be an alternative to grouting to form a watertight zone around freezing pipes. For a proper design of the artificial freezing method, the influence of salinity on the freezing process has to be considered. However, there are few domestic tunnel construction that adopted the artificial freezing method, and influential factors on the freezing of the soil are not clearly identified. In this paper, a series of laboratory experiments were performed to identify the physical characteristics of frozen soil. Thermal conductivity of the frozen and unfrozen soil samples was measured through the thermal sensor adopting transient hot-wire method. Moreover, a lab-scale freezing chamber was devised to simulate freezing process of silica sand with consideration of the salinity of pore-water. The temperature in the silica sand sample was measured during the freezing process to evaluate the effect of pore-water salinity on the frozen rate that is one of the key parameters in designing the artificial freezing method in subsea tunnelling. In case of unfrozen soil, the soil samples saturated with fresh water (salinity of 0%) and brine water (salinity of 3.5%) showed a similar value of thermal conductivity. However, the frozen soil sample saturated with brine water led to the thermal conductivity notably higher than that of fresh water, which corresponds to the fact that the freezing rate of brine water was greater than that of fresh water in the freezing chamber test.

Analysis of Experimental Researches in Korea on the Effects of Aromatherapy to Relieve Pain (아로마테라피의 통증 감소 효과에 관한 국내 실험논문 분석)

  • Park, Jeong-Sook;Park, Jeong-Eon;Yang, Jang-Soon;Kwak, Hye-Weon;Han, Jung-An
    • Journal of Hospice and Palliative Care
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    • v.14 no.1
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    • pp.8-19
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    • 2011
  • Purpose: This study identifies research trends and provides fundamental data related to curative power of aromatherapy to relieve pain in Korea. Methods: The study analyzed 44 experimental studies on humans that were published in Korea before the end of December, 2009. The key words used for searching were: aroma, aromatherapy, hyang-yobeob, hyanggi-yobeob, hyanggichilyo, aromatherapy and pain, headache, scapulodynia, omodynia, feeling uncomfortable in the perineal region, sense of pain, labor pains, arm pain, menstrual pain, aches, and dysmenorrheal. Those words were found on websites, including those for Korea Education & Research Information Service, the National Assembly Library, KISS, KoreaMed, and NDSL. Collected data were analyzed using descriptive statistics. Results: The results showed that most of essential oils to relieve pain is composed of three to four kinds of oils, including Lavender, Roman chamomile, Rosemary, and Clarysage. Aromatherapy is applied usually by means of massage (50%), inhalation (13.6%), or a combination of the above two (13.6%). Measuring instruments as a dependent variable include VAS, questionnaire, GRS, blood pressure, pulse, and Algometer. Aromatherapy plays an important role in soothing headaches and arthralgia. However, when it comes to labor and menstrual pain, it doesn't seem to be effective. Conclusion: The study found that different kinds of oil, frequencies, and periods of time are used for the same symptoms. Further research should employ standardized oil blending, application, duration, and measuring instruments, and more systematically analyze the effects of aromatherapy to establish the effects on relieving pain.