• Defense and Technology
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• no.1 s.263
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• pp.64-77
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• 2001

한국의 방위산업을 육성하기 위해서는 경제적, 군사적 여건과 자원부존 상태 등을 고려한, 적절한 지원 패러다임이 모색되어야 한다. 이런 관점에서 방위산업은 민간 제조업부문의 발전성과를 활용하는 방향으로 육성되어야 하며 인적자본 집약적이고 민수와의 자원.기술 호환성을 극대화하며 기술집약적 구조로의 군구조개편을 지원할 수 있는 업종을 집중 육성하는 동시에 경쟁체제의 강화로 효율성을 높여야 한다. 그리고 지금까지 국방부가 주도해 온 방산육성 시스템을 산업자원부, 과기처, 학계와 연구소 등 비군사 분야가 적극적으로 참여하는 범정부적 시스템으로 확대하여야 한다.

• Journal of Welding and Joining
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• v.14 no.2
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• pp.28-35
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• 1996

플라즈마에 의한 표면경화법(이하 PTA 육성용접이라고 함)은 개발된 이후 필요한 변수가 너무 많아 오랫동안 폭넓게 적용이 되지 못하고 있었다. 따라서 아주 우수한 코팅 품질을 필요로 하거나 재료측면에서 다른 방법을 사용할 수 없는 경우에 만 적용이 되어왔다. 그리고 경제성보다는 안정성이 우선적으로 보장 되어야 하는 경우, 예를 들면, 핵시설물, 화학설비 또한 엔진설비와 같은 곳에 사용이 되었다. 그 러나 최근에 들어서 특별히 microprocessor와 제어기술의 적용이 적은 비용으로도 가능해지면서 새로운 장치가 개발되었고, 많은 연구에 의하여 코팅의 특성에 미치는 영향을 파악하게 되므로써 PTA 육성용접이 신뢰성이 있으며 다른 육성방법에 비해서 우수한 공정으로 자리를 잡게 되었다. 한편 PTA 육성용접은 낮은 dilution, 좁은 열 영향부 그리고 상대적으로 높은 적층율의 특성이 있어 큰 부피를 코팅하거나 중요한 부품에 적용하기에 적합하다. PTA 장치가 반자동 또는 완전 자동화되면서 상대적으로 운용이 쉬워져 이러한 적용성은 더욱 확대되고 있다. PTA 육성용접은 Table 1에서 보는 바와 같이 다른 표면 경화법에 비하여 투자비용은 많이 들더라도 그 특성에 있 어서는 우수하다고 할 수 있다.

• Korean Journal of Crystallography
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• v.10 no.1
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• pp.39-44
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• 1999

주파수 무선센서에 의한 자동직경제어방식으로 쵸크랄스키법에 의해 Bi4Ge3O12 단결정을 육성하였다. Bi4Ge3O12의 화학양론적 조성으로부터 Bi2O3와 GeO2의 조성비를 변화시키면서 단결정을 육성하였다. 광학적인 투과도 조사결과, 화학양론적 조성에서 가장 우수한 투과도를 나타내었고 과잉의 Bi2O3에서는 투과도가 현저히 낮아졌다. 또한 육성된 단결정의 결함밀도는 ∼1×103/cm2이었다.

• The Korea Swine Journal
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• v.15 no.12 s.172
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• pp.74-76
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• 1993

• KOREAN POULTRY JOURNAL
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• v.51 no.10
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• pp.110-113
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• 2019

육계 생산성을 좌우하는 가장 중요한 요소는 건강한 병아리 생산이다. 특히, 종계의 육성과정은 종란을 생산랜 육용종계의 성적에 직접적으로 영향을 주기 때문에 육성과정은 매우 중요하다. 이에 본지는 건강한 병아리 생산을 위해 막대한 사업비를 투자한 전북 정읍에 있는 (주)체리부로 직영농장인 감곡농장을 찾았다.

• Korean Journal of Poultry Science
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• v.46 no.2
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• pp.77-86
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• 2019

This study was conducted to compare the heat stress response and production performance of chicks hatched in winter and summer. Among the 2,090 Korean native chickens examined, 1,156 hatched in winter and 934 hatched in summer. The amount of telomeric DNA, the expression of heat shock protein (HSP) genes, survival rate, egg production, and body weight were analyzed to evaluate the stress response and production performance of chickens. The results showed that the expression of HSP-70, $HSP-90{\alpha}$, and $HSP-90{\beta}$ genes in the winter-hatched chickens were significantly higher than those in the summer-hatched chickens during the growing and laying period (P<0.05). There was no significant difference in the amount of telomeric DNA between summer- and winter-hatched chickens. The survival rate was significantly higher in the summer-hatched chickens than in the winter-hatched chickens at the laying period (P<0.01). The hen-day egg production and egg weight in the summer-hatched chickens were also significantly higher than those in the winter-hatched chickens (P<0.05). In contrast, age of sexual maturity of winter-hatched chickens was significantly earlier than that of summer-hatched chickens (P<0.01). The body weights from birth to 24 weeks were significantly lighter in the summer-hatched chickens than in the winter-hatched chickens, however, it was reversed after 28 weeks (P<0.05). In conclusion, the chicks hatched in the summer are more resistant to heat stress, with better productivity than the chicks hatched in the winter. These results suggest that the chicks grown at high temperatures have greater adaptability to the thermal environment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.44 no.2
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• pp.83-91
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• 2024

We compared the reproductive performance, non-productive performance, and milk composition performance of two groups of lactating cows that were either rice straw or tall fescue. We also compared and analyzed these parameters after the first parturition during the breeding period. The calving interval, artificial insemination, and duration from calving to conception were longer in the rice straw group than in the tall fescue group. The 305-day and peak milk yields were significantly higher in the tall fescue group than in the rice straw group (p<0.01). Milk fat content was significantly higher in the tall fescue group than in the rice straw group (p<0.001), but milk protein content was the same between the feeding groups. The difference in raw milk sales income between rice straw and tall fescue groups tended to increase as the number of lactations increased, but there was no effect of reduced feed costs. Analysis of the milk production and raw milk sales income of the surveyed farms revealed that the average milk production per head was significantly (p<0.05) higher in the tall fescue group than in the rice straw group, and raw milk sales income showed a similar tendency. Overall, these results provide important details to be considered when selecting feed as a way to reduce milk production and heifer raising costs. However, there remains a need for future follow-up studies exploring the relationship between feed choice and the management of heifers.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.4
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• pp.544-549
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• 1998

The single crystal of $KMgCl_3$ was grown in Ar atmosphere by Czochralski method for the first time. For the stoichiometric composition, $K_2MgCl_4$ crystal was obtained, and the nonstoichiometric method was used for the $KMgCl_3$ crystal growth. The phase transition sequences of $KMgCl_3$ were investigated by the DTA, DSC and the ferroelastic properties by using the high temperature polarizing microscope and the thermomechanical system. The temperature dependences of the ferroelastic domains and the spontaneous strain obtained from the stress-strain hysteresis loops were analyzed.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.107-108
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• 2004

산란계 육성기 제한시기 및 제한강도가 육성기 발육형태 및 산란생산성 반응을 구명하고자 1일령 갈색 산란 실용계 Isa-brown 1,000수를 공시하여 70주간 사양시험을 실시하였다. 사료급여 방법은 자유채식구와 제한급이구 9처리를 두었는데, 제한시기는 4, 6 및 8주령으로 하였고 제한강도는 각 시기별 70 %, 85 % 및 12주령 기준으로 70 %에서 85 %로 하는 처리를 두었다. 육성기 사료섭취량은 제한급이시기가 빠를수록 제한강도가 강할수록 자유채식구에 비하여 유의적으로 낮게 나타났다(P<0.05). 산란생산성은 4주령, 85 %구와 6주령 70 % 및 6주령 70 $\longrightarrow$ 85 % 전환구가 가장 우수한 것으로 나타났다. 계란 난각의 품질은 제한급이구가 산란후기에 자유채식구 대비 양호한 것으로 나타났다. 이상의 결과에서 육성기 제한급이는 육성기 사료섭취량을 절감할 수 있으며 생산성과 난각질 향상에 기여할 것으로 판단된다.

• Journal of Animal Environmental Science
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• v.17 no.sup
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• pp.35-42
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• 2011

This work was conducted to investigate the effect of dietary phytase on growth performance and excreta excretion of growing-finishing pigs for 7 days. Eighty three crossbreeds (Yorkshire ${\times}$ Landrace ${\times}$ Duroc) of growing-finishing pigs were used in this work, and divided into 6 treatments. Six treatments were compared in a $2{\times}2$ factorial arrangement with 2 groups (5 replications/group, 8 head/replications) with the additive phytase and 3 groups(growing I, II and finishing phase) with growing phases. Initial weights with growing phases were $58.6{\pm}3.9$. $83.2{\pm}3.8$ and $111.4{\pm}5.4kg$, respectively. Body weight gain was high in phytase treatment (P<0.01) and low at finishing phase. Feed conversion ratio was high in no phytase treatment and at finishing phase (P<0.05). Feed and water intakes have no significant difference with phytase existence and growing phases. Feces excretion decreased with growing phase (P<0.05), and was low at phytase treatment (P<0.05). There was no significant difference on urine excretion (P>0.05). Nitrogen (N) and phosphorus (P) intake was not found significant difference with phytase and growing phases. N excretion had no significant difference on phytase existence and growing phase (P>0.05), but P excretion decreased at phytase treatment (P<0.05). N and P excretion ratio was low at phytase treatment (P<0.05). Finally, dietary phytase resulted in improvement of growth performance and reduction of excreta excretion of growing-finishing pigs.