• 한국산림과학회지
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• 제5권1호
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• pp.4-9
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• 1966

1. On 13 September 1964 a storm raged for 3 hours and 20 minutes with pounding heavy rainfalls, and precipitation of 287.5 mm was recorded on that day. The numerous landslides were occured in the eroded forest land neighbouring Mt. Chunbo, while no landslides recorde at all on Mt. Jookyup within the premise of Kwangnung Experiment Station, the Forest Experiment Station. 2. Small-scalled Landslides were occured in 43 different places of watershed area (21.97 ha.) in which the survey had already been done, in and around Mt. Chunbo (378 m a.s.l.). The accumulated soil amount totaled $2,146,56m^3$ due to the above mentioned landslides, while soil accumulated from riverside erosion has reached to $24,168.79m^3$, consisting of soils, stones, and pebbles. However, no landslides were reported in the Mt. Jook yup area because of dense forest covers. The ratio of the eroded soil amount accumulated from the riversides to that of watershed area was 1 to 25. On the other hand, the loss and damage in the research area of Mt. Chonbo are as follows: 28 houses completly destroyed or missing 7 houses partially destroyed 51 men were dead 5 missing, and 57 wounded. It was a terrible human disaster However, no human casualties were recorded at all, 1 house-completly destroyed and missing, 2 houses-partially destroyed. Total:3 houses were destroyed or damaged, in The area of Mt. Jookyup 3. In the calculation of the quanty of accumulated soil, the or mula of "V=1/3h ($a+{\sqrt{ab}}+b$)" was used and it showed that 24, 168.79m of soil, sands, stones and pebbles carried away. 4. Average slope of the stream stood 15 at the time of accident and well found that there was a correlation between the 87% of cross-area sufferd valley erosion and the length of eroded valley, after a study on regression and correlation of the length and cross-area. In other works, the soil erosion was and severe as we approached to the down-stream, counting at a place of average ($15^{\circ}1^{\prime}$) and below. We might draw a correlation such as "Y=ax-b" in terms of the length and cross-area of the eroded valley. 5. Sites of char-coal pits were found in the upper part of the desert-like Mt. Chunbo and a professional opinion shows that the mountain was once covered by the oak three species. Furthermore, we found that the soil of both mountains have been kept the same soil system according to a research of the soil cross-area. In other words, we can draw out the fact that, originally, the forest type and soil type of both Mt. Chunbo (378m) and Mt. Jookyup (610m) have been and are the same. However, Mt. Chunbo has been much more devastated than Mt. Jookyup, and carried away its soil nutrition to the extent that the ratios of N. $P_2O_5K_2O$ and Humus C.E.C between these two mountains are 1:10;1:5 respectively. 6. Mt. Chunbo has been mostly eroded for the past 30 years, and it consists of gravels of 2mm or larger size in the upper part of the mountain, while in the lower foot part, the sandy loam was formulated due to the fact that the gluey soil has been carried and accumulated. On the hand, Mt. Jookyup has consitantly kept the all the same forest type and sandy loam of brown colour both in the upper and lower parts. 7. As for the capability of absorbing and saturating maximum humidity by the surface soil, the ratios of wet soil to dry soil are 42.8% in the hill side and lower part of the eroded Mt. Chunbo and 28.5% in the upper part. On the contrary, Mt. Jookyup on which the forest type has not been changed, shows that the ratio in 77.4% in the hill-side and 68.2% in the upper part, approximately twice as much humidity as Mt. Chunbo. This proves the fact that the forest lands with dense forest covers are much more capable of maintaining water by wood, vegitation, and an organic material. The strength of dreventing from carring away surface soil is great due to the vigorous network of the root systems. 8. As mentioned above, the devastated forest land cause not only much greater devastation, but also human loss and property damage. We must bear in mind that the eroded forest land has taken the valuable soil, which is the very existance of origin of both human being and all creatures. As for the prescription for preventing erosion of forest land, the trees for furtilization has to be planted in the hill,side with at least reasonable amount of aertilizer, in order to restore the strength of earth soil, while in the lower part, thorough erosion control and reforestation, and establishments along the riversides have to be made, so as to restore the forest type.

• 대한간호학회지
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• 제5권2호
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• pp.74-91
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• 1975

A purpose of this study was to compare the breast massage and manual expression of the breast before engagement after delivery with the time of engagement, the throbbing pain in breast, the first amount of breast milk and involution of the uterus. The subjects selected for this study were 138 women (experimental group;69, control group :69) who were admitted to the Dept. of Obtest. and Gyneco. of Kyung Hee University Hospital from Jan. 5 to June 5, 1975. The results of study were as follows; 1 The average age of the women 26.9 years old in the experimental group and 27.6 years old in the control group. As to religion, the number of those who had no religion was 58.0 percent and 62.4 percent respectively. Classified according to occupation, there were 87.0 percent in house wives of the booths group. Educational background; 87.0 percent of high school graduates or above, 78.3 percent respectively. The occupation of husband 53.7 percent of company employees stood highest and 42.0 percent respectively. In according to the grade of wards, 55.1 percent and 52.2 percent of four-men room stood highest. 2. Physical condition: Body weight before this Pregnancy(T=0.4962, N.S.), the size of breast(X²df2 = 0.1728, N.S.), the shape of nipple(X²df3 =1.3804, N.S.), hemoglobin's level of the first day after delivery(T=1.2572, N.S.), the above were showed non significant between the experimental group and control group The investigator found any difference between the two groups of the health condition during the pregnancy, 3. The rate of no experience of breast massage during pregnancy was 85 percent and 75.4 percent (X²df1=2.2562, N.S.). 4. As to the meal during hospitalization after delivery: The booth of the groups in ordinary food took usually of meyer soup and milk(X²df8=2.5957, N.S.). 5. The relation between the first step of breast massage, second step of the manual expression of breast before engagement after delivery and time of engagement : average time of engagement in the experimental group (2.1 days±0.8) was shortened than the control group (3.3 days±1.2). (T=-6.9045, P< 0.005). It toot less time in the experimental group of primipara(2.2days±0.7) than in the control group (3.1day±1.2) and it also took less time in the experimental group of multipara (2.0 days±0.9) than in the control group (3.5days±1.4). (Primipara T=-3.9266, 0< 0.005. Multipara T= 5.2356, P<0.005). 6. The relationship between the first step of the massage and second step of manual expression and the throbbing pain at the time of engagement: The experimental group showed less effect than control group (X²df4= 27.3342 P<0.005). The separate study of primipara and multipara showed remarkable difference in the group of primipara)X²df4=20.7285, p<0.005) and little difference in the multipara group (X²df4=8.8351, p< 0. 10). 7. The relationship between the first step of the breast massage, second stop of the manual expression and first amount of breast milk: The average amount of breast milk increased more conspicuously in the experimental group (33.8㎖±23.4) than in the control(29.8㎖±25.3) (T=0.8262, N.S.). No remarkable difference was found in the respective groups that investigated in the groups of primipara and of multipara. (Primipara T=1.1467, N.S., Multipara T=-0.0354, N.S.). 8. The relationship between the first step of breast massage and second step of manual expression of breast and involution of uterus : Average time needed for uttering involution was sooner in the experimental group of primipasa(-3.3 F.B.±1.1), than the control group of primipara (-2.5F. B.±1.2), and it was sooner in the experimental group of muitipara (-3.0 F. B.±l..3), than the control group of multipara(-2.3 F.B±0.9). Primipara T=-2.9272, p< 0.005, Multipara T=2.5557, p< 0.01).

• 한국유기농업학회지
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• 제24권4호
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• pp.719-733
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• 2016

본 논문은 앞그루작물 재배 시 형성된 이랑을 재활용하여 다음 뒷그루작물을 무경운으로 재배할 경우 토양의 이화학성과 생육 및 수량에 미치는 영향을 구명하고자 추진한 연구 결과의 일부이다. 토양에서 경운 후 시간의 경과에 따른 토양 입자 크기의 분포를 조사한 결과 관행경운과 무경운 토양 입자는 공히 입상구조(granular structure)를 이루고 있었다. 무경운 토양의 입자 크기 2 mm 이상의 분포는 무경운 토양이 경운 토양에 비하여 표토와 심토 공히 증가 되었다. 그리고 내수성입단 0.25 mm 이상 0.5 mm 이하와 0.5 mm 이상 1 mm 이하, 1 mm 이상의 대입단 분포는 경운과 무경운 1년차 토양에서 유의적인 차이가 없었으나, 무경운 2년차에서는 입단의 크기별로 각각 8.2%, 4.5%, 1.7%로 경운과 무경운 1년차에 비하여 유의적인 증가를 보였다. 관행 경운 토양 표토의 용적밀도 $1.10MG\;m^3$이 무경운 1년차에서 $1.30MG\;m^3$으로 증가 되었으나, 무경운 2년차는 $1.14MG\;m^3$, 무경운 3년차는 $1.03MG\;m^3$으로 용적밀도가 감소되었으며, 심토도 같은 경향이었다. 따라서 용적밀도와 정(+)의 상관이 있는 고상율은 표토와 심토 공히 무경운 1년차에서 관행 경운 토양에 비하여 증가되었으나, 무경운 2년차와 3년차는 감소되었다. 용적밀도 및 고상율과 부(-)의 상관관계가 있는 공극율은 경운 토양 58.5%가 무경운 1년차는 51%로 8.5% 감소되었으나, 무경운 2년차는 56.9%, 무경운 3년차는 61.2%로 증가되었으며, 심토도 같은 경향이었다. 공극율과 정(+)의 상관관계가 있는 기상율은 관행경운 토양에 비하여 무경운 1년차는 감소되었으나, 무경운 2년차와 3년차에서는 증가되었다. 그리고 기상과 함께 공극율을 결정하는 액상율은 경운 표토 24.2%가 무경운 1년차는 28.3%로 증가되었으나, 무경운 2년차는 23.4%, 무경운 3년차는 18.3%로 현저하게 감소되었으며, 심토도 같은 경향이었으나, 심토의 액상율은 표토에 비하여 증가되었다.

• 한국벤처창업학회:학술대회논문집
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• 한국벤처창업학회 2006년 춘계학술발표회
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• pp.167-201
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• 2006

우리나라 기업들은 급변하는 환경을 극복하고 조직의 성과를 높이기 위하여 수직조직을 팀조직으로 전환하고 있다. 그러나 현행 팀제는 조직의 형식만 바꾸었을 뿐 실상은 과거 수직조직과 다름없다는 평가가 많다. 이러한 결과는 팀제의 성공에 필요한 핵심변수인 임파워먼트에 대한 검토와 실행이 되지 않고 있기 때문이다. 본 연구는 KBS 팀제에서 구성원들이 임파워먼트 되는데 걸림돌이 되는 여건이나 심리적 상태들을 파악하여 조직의 임파워먼트를 어떻게 실현할 것인가에 대한 정책적 대안을 제시하고자 한다. 횡단적 연구를 위하여 국내외 문헌조사를 하고 KBS 내에서 회수한 설문결과와 개인면담, 그리고 관찰의견을 종합하여 검토하였다. 설문지는 약 1,200부를 배포해 474부가 수거되어 이 중 460부를 SPSS 12.0 프로그램을 이용하여 분석하였다. 종단적 연구를 위하여 ‘KBS 팀제에 관한 사원의식 조사결과 보고서’ 의 내용과 본 설문조사 연구에서 공통적으로 비교분석할 수 있는 6개 부분을 추출하여 약 10여개윌간의 변화를 비교분석하였다. 분석결과 부정적인 응답자가 24.2%p가 줄어들었고 긍정적인 응답자는 1.29%p가 줄어들었다. 이는 부정적인 평가를 하던 구성원들이 긍정적인 평가자로 전환되어 팀제에 대한 이해가 확산된다는 측면에서 발전적이라 할 수 있으나 문제점에 대한 지속적 해결노력이 필요하다는 것을 시사한다 하겠다. 임파워먼트는 개인과 조직차원에서 생산성을 향상시키는 것으로 증명되었다. 팀 임파워먼트를 높이기 위해서는 경영진이 변혁적 리더십을 발휘해야 하고, 낮게 나타난 경영진과 조직구성원 사이에 신뢰가 무엇보다 먼저 향상되어야 할 것이다. 모든 본부와 직급에서 높게 나타난 업무기피자에 대한 부담이 큰 것으로 확인되었다. 이러한 결과는 전체 팀원에게 고른 업무분담이 되고 있지 못하다는 것을 뜻한다고 볼 수 있다. 그리고 구성원들은 회사의 평가보상시스템을 신뢰하지 않는 것으로 나타났다. 팀의 규모와 업무배정에 좀 더 세심한 배려가 필요하고 평가보상 체계에 사각지대가 생기지 않도록 현행 평가제도를 보완하여야 할 것이다. 리더십은 조직의 특성이나 구성원들의 성향에 따라 각양각색이다. 조직에 맞는 KBS만의 변혁적 리더십, 그리고 팀별로 각각의 특성에 맞는 리더십을 개발하여 운영할 필요가 있다. 또한 팀제의 정착을 위하여 내부 교육과 훈련을 좀 더 강화할 필요가 있다고 판단된다.

• 무역상무연구
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• 제19권
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• pp.224-242
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• 2003

The author believes that the main task of study in international trade usage and practice is the management of transactional risks involved in international sale of goods. They are foreign exchange risks, transportation risks, credit risk, risk of miscommunication, etc. In most cases, these risks are more serious and enormous than those involved in domestic sales. Historically, the merchant adventurers organized the voyage abroad, secured trade finance, and went around the ocean with their own or consigned cargo until around the $mid-19^{th}$ century. They did business faceto-face at the trade fair or the open port where they maintained the local offices, so-called "Trading House"(商館). Thererfore, the transactional risks might have been one-sided either with the seller or the buyer. The bottomry seemed a typical arrangement for risk sharing among the interested parties to the adventure. In this way, such organizational arrangements coped with or bore the transactional risks. With the advent of ocean liner services and wireless communication across the national border in the $19^{th}$ century, the business of merchant adventurers developed toward the clear division of labor; sales by mercantile agents, and ocean transportation by the steam ship companies. The international banking helped the process to be accelerated. Then, bills of lading backed up by the statute made it possible to conduct documentary sales with a foreign partner in different country. Thus, FOB terms including ocean freight and CIF terms emerged gradually as standard trade terms in which transactional risks were allocated through negotiation between the seller and the buyer located in different countries. Both of them did not have to go abroad with their cargo. Instead, documentation in compliance with the terms of the contract(plus an L/C in some cases) must by 'strictly' fulfilled. In other words, the set of contractual documents must be tendered in advance of the arrival of the goods at port of discharge. Trust or reliance is placed on such contractual paper documents. However, the container transport services introduced as international intermodal transport since the late 1960s frequently caused the earlier arrival of the goods at the destination before the presentation of the set of paper documents, which may take 5 to 10% of the amount of transaction. In addition, the size of the container vessel required the speedy transport documentation before sailing from the port of loading. In these circumstances, computerized processing of transport related documents became essential for inexpensive transaction cost and uninterrupted distribution of the goods. Such computerization does not stop at the phase of transportation but extends to cover the whole process of international trade, transforming the documentary sales into less-paper trade and further into paperless trade, i.e., EDI or E-Commerce. Now we face the other side of the coin, which is data security and paperless transfer of legal rights and obligations. Unfortunately, these issues are not effectively covered by a set of contracts only. Obviously, EDI or E-Commerce is based on the common business process and harmonized system of various data codes as well as the standard message formats. This essential feature of E-Commerce needs effective coordination of different divisions of business and tight control over credit arrangements in addition to the standard contract of sales. In a few word, information does not alway invite "trust". Credit flows from people, or close organizational tie-ups. It is our common understanding that, without well-orchestrated organizational arrangements made by leading companies, E-Commerce does not work well for paperless trade. With such arrangements well in place, participating E-business members do not need to seriously care for credit risk. Finally, it is also clear that E-International Commerce must be linked up with a set of government EDIs such as NACCS, Port EDI, JETRAS, etc, in Japan. Therefore, there is still a long way before us to go for E-Commerce in practice, not on the top of information manager's desk.

• 한국농공학회지
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• 제17권4호
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• pp.3943-3955
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• 1975

The purposes of this study are to evaluate the utilization characteristics of electrical power consumption, to grasp the present trends in the use of electrical equipments, to estimate the demand factor and load factor being held, and to evaluate the efficiency of electical uses for the recently electrified farms cultivating paddy rice. For the purposes, 109 sample farms located in eleven villiages electrified in six different years from 1968 to 1973, were chosen at random and investigated on 35 items concerning to electrical uses and wiring systems. The survey was carried out in 1975, in the vinicity of Suweon city. The results are summarized as follows: i) The average annual power consumption on sample farms is considered to be low, being 242.9 Kwh. in 1974, and varied according to the different electrified year and size of cultivated land, respectively. It has significant positive correlation to the area of farm, too. ii) Between the number of year of electrical uses and the power consumption, there is very significant positive correlation, which could be expressed as Y=43.041+16.108 X, where X represents the number of years of electrical uses. The annual increment of power consumption is much greater at the beginning of the electrification than that at the later years, its average being approximately 20 percent. However, it is recommended that any estimation of long-term increments should be carefully investigated. iii) The monthly power consumption varies considerably throughout a year, in which the heaviest farm load occurs in November. Observing the seasonal variation of consumption, the winter-time is the heaviest season while the summer is the lowest. The result implies house lighting is chief contribution to the present electrical consumption on the farms. Comparing the variation of monthly consumption ratios between the sample farms and industries, the electrical uses on the farms are independant of the industrial uses, and further, the agricultural uses are of inverse pattern to the farms from the results that there is negative correlationship between them, iv) The number of electrical equipments used on the farms are occupied chiefly by lighting sources. Next to the lighting sources, household appliances of small quantity and some motors are used. The mean electrical quantity is about 1, 127.4 watt, which corresponds to about 37.6 per cent to the contracted quantity. The composition of quantity is chiefly occupied by the electrical motor of about 1.5 hp., single-phased. The number of the annual utilization hours of each equipment is tabulated in Table IV-5. In contradiction to the high utilization of lighting sources and small household appliances, the motor is poorly used for approximately 22 hours in a year. v) More than 55 per cent of farms want to purchase new electrical equipments such as small household appliances and electrical motors in their number. The impulse of purchasing such items is stimulated by the contacts to the mass media and their knowledge on such equipments. Consequently, the increase of electrical uses could be prompted by such trials as education and demonstration. vi) The demand and load factors on the farms vary considerably according to the greater variation of the power consumption, daily or monthly. The daily demand factor is 22.4 per cent and load factor 18.6 per cent, while the annual demand factor is 1.3 per cent and load factor 70 per cent approximately. Therefore, the low efficiency of construction cost requires re-evaluation of the present contracted quantity of 3 Kw. or increase of electrical uses. vii) The electrical energy on the farms devoted chiefly to lighten the farm residences does not contribute to the farm incomes. Consequently, the cost of electrical consumption presses considerably upon the farm economy. Therefore, there is great need to build up the electrical uses on the farms through the development of new works and techinques to utilize any electrical equipments on the production of farm products. Further more, such the development should be related to increase the actual income of the farm consumers.

• 마케팅과학연구
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• 제19권2호
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• pp.17-26
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• 2009

As the lifestyle of consumers changes and the need for various products increases, new products are being developed in the market. Each household owns various home appliances which are purchased through the choice of a decision maker. These appliances include not only large-sized products such as TV, refrigerator, and washing machine, but also small-sized products such as microwave oven and air cleaner. There exists latent correlation among possession of home appliances, even though they are purchased independently. The purpose of this research is to analyze the effect of demographic factors on the purchase and possession of each home appliances, and to derive some relationships among various appliances. To achieve this purpose, the present status on the possession of each home appliances are investigated through consumer survey data on the electric and energy product. And a multivariate probit(MVP) model is applied for the empirical analysis. From the estimation results, some appliances show a substitutive or complementary pattern as expected, while others which look apparently unrelated have correlation by co-incidence. This research has several advantages compared to previous literatures on home appliances. First, this research focuses on the various products which are purchased by each household, while previous researches such as Matsukawa and Ito(1998) and Yoon(2007) focus just on a particular product. Second, the methodology of this research can consider a choice process of each product and correlation among products simultaneously. Lastly, this research can analyze not only a substitutive or complementary relationship in the same category, but also the correlation among products in the different categories. As the data on the possession of home appliances in each household has a characteristic of multiple choice, not a single choice, a MVP model are used for the empirical analysis. A MVP model is derived from a random utility model, and has an advantage compared to a multinomial logit model in that correlation among error terms can be derive(Manchanda et al., 1999; Edwards and Allenby, 2003). It is assumed that the error term has a normal distribution with zero mean and variance-covariance matrix ${\Omega}$. Hence, the sign and value of correlation coefficients means the relationship between two alternatives(Manchanda et al., 1999). This research uses the data of 'TEMEP Household ICT/Energy Survey (THIES) 2008' which is conducted by Technology Management, Economics and Policy Program in Seoul National University. The empirical analysis of this research is accomplished in two steps. First, a MVP model with demographic variables is estimated to analyze the effect of the characteristics of household on the purchase of each home appliances. In this research, some variables such as education level, region, size of family, average income, type of house are considered. Second, a MVP model excluding demographic variables is estimated to analyze the correlation among each home appliances. According to the estimation results of variance-covariance matrix, each households tend to own some appliances such as washing machine-refrigerator-cleaner-microwave oven, and air conditioner-dish washer-washing machine and so on. On the other hand, several products such as analog braun tube TV-digital braun tube TV and desktop PC-portable PC show a substitutive pattern. Lastly, the correlation map of home appliances are derived using multi-dimensional scaling(MDS) method based on the result of variance-covariance matrix. This research can provide significant implications for the firm's marketing strategies such as bundling, pricing, display and so on. In addition, this research can provide significant information for the development of convergence products and related technologies. A convergence product can decrease its market uncertainty, if two products which consumers tend to purchase together are integrated into it. The results of this research are more meaningful because it is based on the possession status of each household through the survey data.

• 한국임상수의학회지
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• 제23권2호
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• pp.105-110
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• 2006

2003년 5월부터 2005년 11월까지 산란계의 전염성기관지염(IB) 예찰 프로그램에 등록한 농장에 대한 역학조사에서 얻은 자료에 근거하여 IB 감염을 확인할 수 있는 모형을 구축하기 위하여 16개의 입력 뉴런, 3 개의 은닉 뉴런, 1개의 출력 뉴런으로 구성된 3층 인공신경망 모형을 개발하였다. 총 86개의 계군 중 77개는 훈련자료에 할당하고 나머지 9개는 검정자료로 무작위로 할당하여 back-propagation algorithm으로 신경망 훈련을 수행하였다. 입력 뉴런은 산란계군의 특성, 사양관리, 계군의 크기 등 16개의 역학조사 항목을 사용하였으며 출력 뉴런은 IB 감염의 유무로 투입하였다. 훈련된 신경망을 검정자료에 적용하여 민감도와 특이도를 산출하였으며 진단의 정확도는 receiver operating characteristic (ROC) 곡선을 사용하여 곡선 밑의 면적(AUC)을 계산하여 평가하였다. 입력 뉴런의 특성과 훈련모수를 변경하면서 다양한 신경망을 구성하였으며 최적의 신경망으로 확인된 IBV_D1 신경망의 경우 훈련자료에 대하여 77건 중 73건을 올바르게 판단하여 94.8%의 정확도를 보였다. 민감도와 특이도는 각각 95.5% (42/44, 95% CI, 84.5-99.4)와 93.9% (31/33, 95% CI, 79.8-99.3)로 나타났다. 훈련된 신경망을 검정자료에 적용하여 ROC 곡선을 작성한 결과 AUC는 전체의 94.8% (SE=0.086, 95% CI 0.592-0.961)를 차지하는 우수한 모형으로 나타났다. ROC 곡선에서 기준을 0.7149 이상으로 판단할 때 진단의 정확도가 88.9%로 가장 높았으며 100%의 민감도를 달성하였다. 이러한 민감도와 특이도에서 44%의 IB 유병률을 가정할 때 IBV_D1 모형은 80%의 양성예측도와 100%의 음성예측도를 보였다. 이러한 소견에 근거할 때 본 연구에서 구축한 신경망 모형은 산란계군에서 IB의 존재를 확인하기 위한 목적에 성공적으로 응용될 수 있을 것으로 판단되었다.

• 생태와환경
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• 제42권3호
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• pp.290-294
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• 2009

본 연구에서는 꼬마잠자리 유충의 성장률을 밝히고자 인공습지서식처를 조성하고 자연개체군을 이식하여 실험하였다. 인공서식처는 꼬마잠자리가 서식하고 있는 충남 보령시의 자연서식처를 모방하여 온실(비닐하우스)안에 조성하였다. 2007년 6월에 300개체의 꼬마잠자리 유충을 인공서식처에 도입하였으며, 2007년 6월부터 2008년 11월까지 유충의 체장을 측정하고자 5차례의 재포획을 실시하였다. 실험의 결과, 처음 개체군과 재포획 개체군(재포획 I, II, III, IV, V 개체군)에서 모두 체장의 크기가 2개의 그룹으로 나뉘어졌다[처음 개체군 6.20$\pm$0.34 mm 및 7.94$\pm$0.46 mm (평균$\pm$분산); 재포획 I 12.84$\pm$0.43 mm 및 5.16$\pm$0.83 mm; 재포획 II 5.96$\pm$0.66 mm 및 8.02$\pm$0.35 mm; 재포획 III 5.97$\pm$0.73 mm 및 7.82$\pm$0.37 mm; 재포획 IV 7.04$\pm$0.93 mm 및 8.52$\pm$0.39 mm; 재포획 V 5.72$\pm$0.60 mm 및 7.71$\pm$0.30 mm]. 본 실험의 결과는 재포획 I$\sim$V의 개체군은 처음 개체군의 자손이며, 이들은 온일도가 470 일 때 약 3mm성장한 것으로 나타났다. 따라서 꼬마잠자리의 성장률은 온일도가 100일 때 약 0.7 mm 자라는 것으로 추정된다.

• Journal of Nutrition and Health
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• 제41권8호
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• pp.776-785
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• 2008

본 연구는 서울소재의 종합병원 산부인과에 외래로 방문한 임신부 248명을 대상으로 설문조사를 실시하였고, 임신 중 스트레스 정도와 영양섭취상태 및 임신결과와의 관계를 알아보고자 하였다. 조사를 통해 얻어진 결과를 요약하면 다음과 같다. 1) 조사대상자의 나이는 두 군이 비슷하였고, 스트레스 낮은 군이 스트레스 높은 군보다 교육수준, 경제 수준이 약간 높았으나 통계적으로 유의한 차이는 없었다. 스트레스 낮은 군은 스트레스 높은 군에 비해 취업률이 높게 나타났다 (p < 0.05). 가족 수에서는 스트레스 높은 군이 스트레스 낮은 군보다 3인 이상 가족구성의 비율이 높았다 (p < 0.01). 2) 신체 계측치에서 스트레스 높은 군이 키가 작고 임신전 체중이 높았으나 통계적인 유의성은 없었다. 임신 전 BMI는 스트레스 낮은 군보다 스트레스 높은 군에서 과체중 및 비만이 유의적으로 높았다 (p < 0.05). 3) 임신 중 활동은 스트레스 낮은 군이 스트레스 높은 군보다 가벼운 정도의 활동을 하고 있었으며 (p < 0.05), 임신 중 규칙적인 운동은 스트레스 낮은 군이 스트레스 높은 군보다 더 많이 하고 있었다 (p < 0.01). 4) 임신 중 스트레스 요인으로는‘아기에 대한 걱정’ (40.4%),‘건강에 대한 걱정’ (28.8%),‘경제적 어려움’ (13.2%),‘우울감’ (10.1%),‘가족관계’ (2.9%),‘가사 일에 대한 걱정’ (2.5%),‘인간관계’ (2%) 순으로 나타났다. 5) 대부분의 영양소섭취는 스트레스가 낮은 군이 스트레스가 높은 군보다 약간 많았으나 통계적 유의성은 없었다. 엽산, 칼륨, 칼슘, 철의 섭취는 KDRI의 2/3에도 못 미치는 수준이었고 나트륨, 콜레스테롤, 인, 비타민 E는 KDRI의 150% 이상 섭취하고 있었다. 6) 임신 중 스트레스와 섭취한 영양소와의 관계를 보았을 때, 대부분의 영양소와 통계적으로 유의성을 보이지 않았다. 하지만 지방, 콜레스테롤은 섭취량이 많을수록 스트레스 발생 위험도가 높아지는 경향을 보였고, 당질, 식이섬유는 섭취량이 많을수록 스트레스 발생 위험도가 감소하는 경향을 보였다. 7) 스트레스 정도는 두 군에서 임신부의 재태기간, 체중증가량, 신생아 출생 시 체중, 신장 및 Apgar scores와 통계적으로 유의한 차이를 보이지 않았다. 본 연구에서 임신 중 스트레스는 신생아의 건강에 대한 염려, 임신부의 처해있는 경제여건, 사회적 지위나 생활여건, 임신과 관련된 상황, 자신의 성격 및 배우자를 포함한 가족 관계 등 다양한 요인에 의해 나타났다. 본 연구 결과 스트레스 높은 군이 스트레스 낮은 군보다 취업률이 낮았고, 임신전 BMI가 비만 및 과체중군이 많았으며, 임신 중 규칙적인 운동을 하고 있지 않았다. 이런 생활습관들이 임신 중 스트레스에 영향을 미치는 것으로 사료된다. 하지만 임신 중 스트레스는 대부분의 영양섭취상태와 임신결과에 직접적인 영향을 미치지 않았다. 스트레스와 영양소 섭취와의 관련성이 뚜렷하게 나타나지 않은 것은 본 연구에서 임신부의 2일간 식이회상법 자료를 이용해 영양소 섭취실태를 조사하였기에 임신부의 평소식사를 반영하는데 한계가 있었기 때문으로 사료된다. 본 연구에서 임신 중 스트레스를 예방하기 위해서는 적절한 체중관리와 규칙적인 운동이 도움이 될 수 있다는 것을 확인하였다.